4802

Some automated commenting cleanup. Still needs more careful manual scanning.

  sed -i 's/^#   1-3/# . 1-3/' *.subx */*.subx
  sed -i 's/^#   op/# . op/' *.subx */*.subx
  sed -i 's/# vim/# . . vim/' *.subx */*.subx
  sed -i 's/^    # push args/    # . . push args/' *.subx */*.subx
  sed -i 's/^    # discard args/    # . . discard args/' *.subx */*.subx
  sed -i 's/^    # call/    # . . call/' *.subx */*.subx
  sed -i 's/^    # prolog/    # . prolog/' *.subx */*.subx
  sed -i 's/^    # epilog/    # . epilog/' *.subx */*.subx
  sed -i 's/^    # save registers/    # . save registers/' *.subx */*.subx
  sed -i 's/^    # restore registers/    # . restore registers/' *.subx */*.subx
  sed -i 's/  operand  /  register /' *.subx */*.subx

26 files changed, 828 insertions, 828 deletions

diff --git a/subx/050_write.subx b/subx/050_write.subx
index 1975f7a3..bb0f20e1 100644
--- a/subx/050_write.subx
+++ b/subx/050_write.subx
@@ -1,9 +1,9 @@
 # _write: write to a file descriptor
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     # syscall(exit, 0) -- can't test _write just yet
@@ -12,34 +12,34 @@
     cd/syscall  0x80/imm8
 
 _write:  # fd : int, s : (address array byte) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     52/push-EDX
     53/push-EBX
     # syscall(write, fd, (data) s+4, (size) *s)
-    # fd : EBX
+    # . fd : EBX
     8b/copy                         1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           3/r32/EBX   8/disp8         .                 # copy *(EBP+8) to EBX
-    # data : ECX = s+4
+    # . data : ECX = s+4
     8b/copy                         1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           1/r32/ECX   0xc/disp8       .                 # copy *(EBP+12) to ECX
     81          0/subop/add         3/mod/direct    1/rm32/ECX    .           .             .           .           .               4/imm32           # add to ECX
-    # size : EDX = *s
+    # . size : EDX = *s
     8b/copy                         1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           2/r32/EDX   0xc/disp8       .                 # copy *(EBP+12) to EDX
     8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           2/r32/EDX   .               .                 # copy *EDX to EDX
-    # syscall
+    # . syscall
     b8/copy-to-EAX  4/imm32/write
     cd/syscall  0x80/imm8
-    # restore registers
+    # . restore registers
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/051test.subx b/subx/051test.subx
index e665793a..2f93c914 100644
--- a/subx/051test.subx
+++ b/subx/051test.subx
@@ -1,9 +1,9 @@
 # Rudimentary test harness
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:  (manual test if this is the last file loaded)
     # check-ints-equal(34, 34)
@@ -19,10 +19,10 @@
 
 # print msg to stderr if a != b, otherwise print "."
 check-ints-equal:  # (a : int, b : int, msg : (address array byte)) -> boolean
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     53/push-EBX
     # load first 2 args into EAX and EBX
@@ -32,41 +32,41 @@ check-ints-equal:  # (a : int, b : int, msg : (address array byte)) -> boolean
     39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # compare EAX and EBX
     75/jump-if-unequal  $check-ints-equal:else/disp8
     # _write(2/stderr, '.')
-      # push args
+    # . . push args
     68/push  "."/imm32
     68/push  2/imm32/stderr
-      # call
+    # . . call
     e8/call  _write/disp32
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # return
     eb/jump  $check-ints-equal:end/disp8
     # else:
 $check-ints-equal:else:
     # _write(2/stderr, msg)
-      # push args
+    # . . push args
     8b/copy                         1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           1/r32/ECX   0x10/disp8      .                 # copy *(EBP+16) to ECX
     51/push-ECX
     68/push  2/imm32/stderr
-      # call
+    # . . call
     e8/call  _write/disp32
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # _write(2/stderr, Newline)
-      # push args
+    # . . push args
     68/push  Newline/imm32
     68/push  2/imm32/stderr
-      # call
+    # . . call
     e8/call  _write/disp32
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # increment Num-test-failures
     ff          0/subop/increment   0/mod/indirect  5/rm32/.disp32            .             .           .           Num-test-failures/disp32          # increment *Num-test-failures
 $check-ints-equal:end:
-    # restore registers
+    # . restore registers
     5b/pop-to-EBX
     59/pop-to-ECX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -82,4 +82,4 @@ Newline:
 Num-test-failures:
     00 00 00 00
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/052kernel_string_equal.subx b/subx/052kernel_string_equal.subx
index 3eb0158c..696f0f8f 100644
--- a/subx/052kernel_string_equal.subx
+++ b/subx/052kernel_string_equal.subx
@@ -15,9 +15,9 @@
 # would cause tests to not run, rather than to fail as we'd like.)
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
@@ -29,10 +29,10 @@
 # compare a null-terminated ascii string with a more idiomatic length-prefixed byte array
 # reason for the name: the only place we should have null-terminated ascii strings is from commandline args
 kernel-string-equal:  # s : null-terminated ascii string, benchmark : length-prefixed ascii string -> EAX : boolean
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     52/push-EDX
     53/push-EBX
@@ -98,13 +98,13 @@ $kernel-string-equal:false:
     b8/copy-to-EAX  0/imm32
 
 $kernel-string-equal:end:
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -113,141 +113,141 @@ $kernel-string-equal:end:
 
 test-compare-null-kernel-string-with-empty-array:
     # EAX = kernel-string-equal(Null-kernel-string, "")
-    # push args
+    # . . push args
     68/push  ""/imm32
     68/push  Null-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 1, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 1, msg)
+    # . . push args
     68/push  "F - test-compare-null-kernel-string-with-empty-array"/imm32
     68/push  1/imm32/true
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-null-kernel-string-with-non-empty-array:
     # EAX = kernel-string-equal(Null-kernel-string, "Abc")
-    # push args
+    # . . push args
     68/push  "Abc"/imm32
     68/push  Null-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 0, msg)
+    # . . push args
     68/push  "F - test-compare-null-kernel-string-with-non-empty-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-equal-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "Abc")
-    # push args
+    # . . push args
     68/push  "Abc"/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 1, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 1, msg)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-equal-array"/imm32
     68/push  1/imm32/true
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-inequal-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "Adc")
-    # push args
+    # . . push args
     68/push  "Adc"/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 0, msg)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-equal-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-empty-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "")
-    # push args
+    # . . push args
     68/push  ""/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0)
-    # push args
+    # . . call check-ints-equal(EAX, 0)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-equal-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-shorter-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0)
-    # push args
+    # . . call check-ints-equal(EAX, 0)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-shorter-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-longer-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "Abcd")
-    # push args
+    # . . push args
     68/push  "Abcd"/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0)
-    # push args
+    # . . call check-ints-equal(EAX, 0)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-longer-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
@@ -258,4 +258,4 @@ Null-kernel-string:
 Abc-kernel-string:
     41/A 62/b 63/c 00/null
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/053new_segment.subx b/subx/053new_segment.subx
index 69115575..3809eee5 100644
--- a/subx/053new_segment.subx
+++ b/subx/053new_segment.subx
@@ -1,17 +1,17 @@
 # Create a new segment (for data) using mmap().
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:  (manual test if this is the last file loaded)
     # EAX = new-segment(0x1000)
-    # push args
+    # . . push args
     68/push  0x1000/imm32
-    # call
+    # . . call
     e8/call  new-segment/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32                 # add to ESP
 
     # store to *EAX
@@ -23,7 +23,7 @@
     cd/syscall  0x80/imm8
 
 new-segment:  # len : int -> address
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                       # copy ESP to EBP
     53/push-EBX
@@ -36,7 +36,7 @@ new-segment:  # len : int -> address
     bb/copy-to-EBX  mmap-new-segment/imm32
     b8/copy-to-EAX  0x5a/imm32/mmap
     cd/syscall  0x80/imm8
-    # epilog
+    # . epilog
     5b/pop-to-EBX
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                       # copy EBP to ESP
     5d/pop-to-EBP
@@ -59,4 +59,4 @@ mmap-new-segment:  # type mmap_arg_struct
     # offset
     00 00 00 00  # 0 since MAP_ANONYMOUS is specified
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/054string_equal.subx b/subx/054string_equal.subx
index 2b0d6006..44222e1e 100644
--- a/subx/054string_equal.subx
+++ b/subx/054string_equal.subx
@@ -1,9 +1,9 @@
 # Comparing 'regular' length-prefixed strings.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
@@ -13,10 +13,10 @@
     cd/syscall  0x80/imm8
 
 string-equal:  # s : string, benchmark : string -> EAX : boolean
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     52/push-EDX
     53/push-EBX
@@ -74,12 +74,12 @@ $string-equal:false:
     # return false
     b8/copy-to-EAX  0/imm32
 $string-equal:end:
-    # restore registers
+    # . restore registers
     5e/pop-to-ESI
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -88,82 +88,82 @@ $string-equal:end:
 
 test-compare-empty-with-empty-string:
     # EAX = string-equal("", "")
-    # push args
+    # . . push args
     68/push  ""/imm32
     68/push  ""/imm32
-    # call
+    # . . call
     e8/call  string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 1, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 1, msg)
+    # . . push args
     68/push  "F - test-compare-empty-with-empty-string"/imm32
     68/push  1/imm32/true
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-empty-with-non-empty-string:  # also checks length-mismatch code path
     # EAX = string-equal("", "Abc")
-    # push args
+    # . . push args
     68/push  "Abc"/imm32
     68/push  ""/imm32
-    # call
+    # . . call
     e8/call  string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 0, msg)
+    # . . push args
     68/push  "F - test-compare-empty-with-non-empty-string"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-equal-strings:
     # EAX = string-equal("Abc", "Abc")
-    # push args
+    # . . push args
     68/push  "Abc"/imm32
     68/push  "Abc"/imm32
-    # call
+    # . . call
     e8/call  string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 1, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 1, msg)
+    # . . push args
     68/push  "F - test-compare-equal-strings"/imm32
     68/push  1/imm32/true
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-inequal-strings-equal-lengths:
     # EAX = string-equal("Abc", "Adc")
-    # push args
+    # . . push args
     68/push  "Adc"/imm32
     68/push  "Abc"/imm32
-    # call
+    # . . call
     e8/call  string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 0, msg)
+    # . . push args
     68/push  "F - test-compare-inequal-strings-equal-lengths"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/055trace.subx b/subx/055trace.subx
index 7986cf33..2f281ced 100644
--- a/subx/055trace.subx
+++ b/subx/055trace.subx
@@ -38,9 +38,9 @@ _test-trace-stream:
     00 00 00 00 00 00 00 00  # 8 bytes
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
@@ -53,11 +53,11 @@ _test-trace-stream:
 # The Trace-stream segment will consist of variable-length lines separated by newlines (0x0a)
 initialize-trace-stream:
     # EAX = new-segment(0x1000)
-    # push args
+    # . . push args
     68/push  0x1000/imm32/N
-    # call
+    # . . call
     e8/call  new-segment/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # copy EAX to *Trace-stream
     89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Trace-stream/disp32               # copy EAX to *Trace-stream
@@ -68,10 +68,10 @@ initialize-trace-stream:
 # Append a string to the given trace stream.
 # Silently give up if it's already full. Or truncate the string if there isn't enough room.
 trace:  # t : (address trace-stream), line : string
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     52/push-EDX
@@ -95,9 +95,9 @@ trace:  # t : (address trace-stream), line : string
     # push &t->data[t->write]
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    7/base/EDI  1/index/ECX   .           3/r32/EBX   0xc/disp8       .                 # copy EDI+ECX+12 to EBX
     53/push-EBX
-    # call
+    # . . call
     e8/call  _append-3/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # if EAX == 0 return
     81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # compare EDX
@@ -115,30 +115,30 @@ trace:  # t : (address trace-stream), line : string
     # push &t->data[t->write]
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    7/base/EDI  1/index/ECX   .           3/r32/EBX   0xc/disp8       .                 # copy EDI+ECX+12 to EBX
     53/push-EBX
-    # call
+    # . . call
     e8/call  _append-3/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # t->write += EAX
     01/add                          0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # add EAX to *EDI
 $trace:end:
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 clear-trace-stream:  # t : (address trace-stream)
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     # EAX = t
@@ -164,10 +164,10 @@ $clear-trace-stream:loop:
     81          0/subop/add         3/mod/direct    0/rm32/EAX    .           .             .           .           .               4/imm32           # add to EAX
     eb/jump  $clear-trace-stream:loop/disp8
 $clear-trace-stream:end:
-    # restore registers
+    # . restore registers
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -176,98 +176,98 @@ $clear-trace-stream:end:
 
 test-trace-single:
     # clear-trace-stream(_test-trace-stream)
-    # push args
+    # . . push args
     68/push  _test-trace-stream/imm32
-    # call
+    # . . call
     e8/call  clear-trace-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # trace(_test-trace-stream, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  _test-trace-stream/imm32
-    # call
+    # . . call
     e8/call  trace/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(*_test-trace-stream.data, 41/A 62/b 0a/newline 00, msg)
-    # push args
+    # . . push args
     68/push  "F - test-trace-single"/imm32
     68/push  0x0a6241/imm32/Ab-newline
     # push *_test-trace-stream.data
     b8/copy-to-EAX  _test-trace-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
 
 test-trace-appends:
     # clear-trace-stream(_test-trace-stream)
-    # push args
+    # . . push args
     68/push  _test-trace-stream/imm32
-    # call
+    # . . call
     e8/call  clear-trace-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # trace(_test-trace-stream, "C")
-    # push args
+    # . . push args
     68/push  "C"/imm32
     68/push  _test-trace-stream/imm32
-    # call
+    # . . call
     e8/call  trace/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # trace(_test-trace-stream, "D")
-    # push args
+    # . . push args
     68/push  "D"/imm32
     68/push  _test-trace-stream/imm32
-    # call
+    # . . call
     e8/call  trace/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(*_test-trace-stream.data, 43/C 0a/newline 44/D 0a/newline, msg)
-    # push args
+    # . . push args
     68/push  "F - test-trace-appends"/imm32
     68/push  0x0a440a43/imm32/C-newline-D-newline
     # push *_test-trace-stream.data
     b8/copy-to-EAX  _test-trace-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
 
 test-trace-empty-line:
     # clear-trace-stream(_test-trace-stream)
-    # push args
+    # . . push args
     68/push  _test-trace-stream/imm32
-    # call
+    # . . call
     e8/call  clear-trace-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # trace(_test-trace-stream, "")
-    # push args
+    # . . push args
     68/push  ""/imm32
     68/push  _test-trace-stream/imm32
-    # call
+    # . . call
     e8/call  trace/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(*_test-trace-stream.data, 0, msg)
-    # push args
+    # . . push args
     68/push  "F - test-trace-empty-line"/imm32
     68/push  0/imm32
     # push *_test-trace-stream.data
     b8/copy-to-EAX  _test-trace-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -276,10 +276,10 @@ test-trace-empty-line:
 
 # 3-argument variant of _append
 _append-3:  # out : address, outend : address, s : (array byte) -> num_bytes_appended/EAX
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     # _append-4(out, outend, &s.data[0], &s.data[s.length]) -> num_bytes_appended/EAX
     # push &s.data[s.length]
@@ -297,23 +297,23 @@ _append-3:  # out : address, outend : address, s : (array byte) -> num_bytes_app
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
     # push out
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x8/disp8       .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  _append-4/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
-    # restore registers
+    # . restore registers
     59/pop-to-ECX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 # 4-argument variant of _append
 _append-4:  # out : address, outend : address, in : address, inend : address -> num_bytes_appended/EAX
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     52/push-EDX
     53/push-EBX
@@ -345,15 +345,15 @@ $_append-4:loop:
     47/increment-EDI
     eb/jump  $_append-4:loop/disp8
 $_append-4:end:
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/056write.subx b/subx/056write.subx
index cf2c3194..6638b174 100644
--- a/subx/056write.subx
+++ b/subx/056write.subx
@@ -16,9 +16,9 @@
 #   data: (array byte)  # prefixed by length as usual
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
@@ -31,23 +31,23 @@ write:  # f : fd or (address stream), s : (address array byte) -> bytes_written/
     # (If we ever leave the Linux kernel behind, it may be better to return
     # the number of bytes *not* written. Success would then be signaled by
     # returning 0.)
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # if (f < 0x08000000) _write(f, s), return  # f can't be a user-mode address, so treat it as a kernel file descriptor
     81          7/subop/compare     1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         0x08000000/imm32  # compare *(EBP+8)
     7d/jump-if-greater-or-equal  $write:fake/disp8
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  _write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     eb/jump  $write:end/disp8
 $write:fake:
     # otherwise, treat 'f' as a stream to append to
-    # save registers
+    # . save registers
     51/push-ECX
     52/push-EDX
     53/push-EBX
@@ -66,27 +66,27 @@ $write:fake:
     # push &f->data[f->write]
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    1/base/ECX  2/index/EDX   .           3/r32/EBX   0xc/disp8       .                 # copy ECX+EDX+12 to EBX
     53/push-EBX
-    # call
+    # . . call
     e8/call  _append-3/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # f->write += EAX
     01/add                          0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # add EAX to *ECX
-    # restore registers
+    # . restore registers
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
 $write:end:
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 clear-stream:  # f : (address stream) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     # EAX = f
@@ -112,87 +112,87 @@ $clear-stream:loop:
     81          0/subop/add         3/mod/direct    0/rm32/EAX    .           .             .           .           .               4/imm32           # add to EAX
     eb/jump  $clear-stream:loop/disp8
 $clear-stream:end:
-    # restore registers
+    # . restore registers
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 test-write-single:
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(EAX, 2)
-    # push args
+    # . . push args
     68/push  "F - test-read-single: return EAX"/imm32
     68/push  2/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # check-ints-equal(*_test-stream->data, 41/A 62/b 00 00, msg)
-    # push args
+    # . . push args
     68/push  "F - test-write-single"/imm32
     68/push  0x006241/imm32/Ab
     # push *_test-stream->data
     b8/copy-to-EAX  _test-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
 
 test-write-appends:
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream, "C")
-    # push args
+    # . . push args
     68/push  "C"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(_test-stream, "D")
-    # push args
+    # . . push args
     68/push  "D"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(*_test-stream->data, 43/C 44/D 00 00, msg)
-    # push args
+    # . . push args
     68/push  "F - test-write-appends"/imm32
     68/push  0x00004443/imm32/C-D
     # push *_test-stream->data
     b8/copy-to-EAX  _test-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -209,4 +209,4 @@ _test-stream:
     # data
     00 00 00 00 00 00 00 00  # 8 bytes
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/057stop.subx b/subx/057stop.subx
index 483c9404..b9ef4467 100644
--- a/subx/057stop.subx
+++ b/subx/057stop.subx
@@ -33,9 +33,9 @@
 # Its value is its output, computed during stop and available to the test.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
@@ -49,10 +49,10 @@
 # the stack.
 # Ugly that we need to know the size of args, but so it goes.
 tailor-exit-descriptor:  # ed : (address exit-descriptor), nbytes : int -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     # EAX = nbytes
@@ -65,7 +65,7 @@ tailor-exit-descriptor:  # ed : (address exit-descriptor), nbytes : int -> <void
     # That's the value we need to return: X-nbytes-4
     #
     # However, we also need to account for the perturbance to ESP caused by the
-    # call to tailor-exit-descriptor. It pushes 8 bytes of args followed by 4
+    # . . call to tailor-exit-descriptor. It pushes 8 bytes of args followed by 4
     # bytes for the return address and 4 bytes to push EBP above.
     # So EBP at this point is X-16.
     #
@@ -87,10 +87,10 @@ tailor-exit-descriptor:  # ed : (address exit-descriptor), nbytes : int -> <void
     89/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy EAX to *ECX
     # initialize ed->value
     c7/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # copy to *(ECX+4)
-    # restore registers
+    # . restore registers
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -132,78 +132,78 @@ test-stop-skips-returns-on-exit:
     8d/copy-address                 0/mod/indirect  4/rm32/sib    4/base/ESP  4/index/none  .           0/r32/EAX   .               .                 # copy ESP to EAX
     # Size the exit-descriptor precisely for the next call below, to _test-stop-1.
     # tailor-exit-descriptor(ed, 4)
-    # push args
+    # . . push args
     68/push  4/imm32/nbytes-of-args-for-_test-stop-1
     50/push-EAX
-    # call
+    # . . call
     e8/call  tailor-exit-descriptor/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call _test-stop-1(ed)
-    # push args
+    # . . call _test-stop-1(ed)
+    # . . push args
     50/push-EAX
-    # call
+    # . . call
     e8/call  _test-stop-1/disp32
     ## registers except ESP may be clobbered at this point
     # restore args
     58/pop-to-EAX
     # check that _test-stop-1 tried to call exit(1)
     # check-ints-equal(ed->value, 2, msg)  # i.e. stop was called with value 1
-    # push args
+    # . . push args
     68/push  "F - test-stop-skips-returns-on-exit"/imm32
     68/push  2/imm32
     # push ed->value
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
-    # epilog
+    # . epilog
     5d/pop-to-EBP
     # don't restore ESP from EBP; manually reclaim locals
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     c3/return
 
 _test-stop-1:  # ed : (address exit-descriptor)
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # _test-stop-2(ed)
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  _test-stop-2/disp32
     ## should never get past this point
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # signal test failed: check-ints-equal(1, 0, msg)
-    # push args
+    # . . push args
     68/push  "F - test-stop-skips-returns-on-exit"/imm32
     68/push  0/imm32
     68/push  1/imm32
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 _test-stop-2:  # ed : (address exit-descriptor)
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # call stop(ed, 1)
-    # push args
+    # . . call stop(ed, 1)
+    # . . push args
     68/push  1/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  stop/disp32
     ## should never get past this point
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/058read.subx b/subx/058read.subx
index 54f83f0f..ccd7e349 100644
--- a/subx/058read.subx
+++ b/subx/058read.subx
@@ -41,9 +41,9 @@
 #   data: (array byte)  # prefixed by length as usual
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
@@ -53,24 +53,24 @@
     cd/syscall  0x80/imm8
 
 read:  # f : fd or (address stream), s : (address stream) -> num-bytes-read/EAX
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     ## if (f < 0x08000000) return _read(f, s)  # f can't be a user-mode address, so treat it as a kernel file descriptor
     81          7/subop/compare     1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         0x08000000/imm32  # compare *(EBP+8)
     7d/jump-if-greater-or-equal  $read:fake/disp8
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  _read/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # return
     eb/jump  $read:end/disp8
 $read:fake:
     ## otherwise, treat 'f' as a stream to scan from
-    # save registers
+    # . save registers
     56/push-ESI
     57/push-EDI
     # ESI = f
@@ -95,19 +95,19 @@ $read:fake:
     8b/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy *EDI to EAX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    7/base/EDI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy EDI+EAX+12 to EAX
     50/push-EAX
-    # call
+    # . . call
     e8/call  _append-4/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
     # s->write += EAX
     01/add                          0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # add EAX to *EDI
     # f.read += EAX
     01/add                          1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # add EAX to *(ESI+4)
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
 $read:end:
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -119,10 +119,10 @@ $read:end:
 # Maybe a better helper would be 'empty-stream?'
 
 _read:  # fd : int, s : (address stream) -> num-bytes-read/EAX
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     52/push-EDX
     53/push-EBX
@@ -145,12 +145,12 @@ _read:  # fd : int, s : (address stream) -> num-bytes-read/EAX
     cd/syscall  0x80/imm8
     # add the result EAX to s->write
     01/add                          0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # add EAX to *ESI
-    # restore registers
+    # . restore registers
     5e/pop-to-ESI
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -180,54 +180,54 @@ _read:  # fd : int, s : (address stream) -> num-bytes-read/EAX
 
 test-read-single:
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-stream-buffer)
-    # push args
+    # . . push args
     68/push  _test-stream-buffer/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # read(_test-stream, _test-stream-buffer)
-    # push args
+    # . . push args
     68/push  _test-stream-buffer/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  read/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(EAX, 2)
-    # push args
+    # . . push args
     68/push  "F - test-read-single: return EAX"/imm32
     68/push  2/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # check-ints-equal(*_test-stream-buffer->data, 41/A 62/b 00 00, msg)
-    # push args
+    # . . push args
     68/push  "F - test-read-single"/imm32
     68/push  0x006241/imm32/Ab
     # push *_test-stream-buffer->data
     b8/copy-to-EAX  _test-stream-buffer/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -235,61 +235,61 @@ test-read-single:
 test-read-is-stateful:
     ## make two consecutive reads, check that their results are appended
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-stream-buffer)
-    # push args
+    # . . push args
     68/push  _test-stream-buffer/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream, "C")
-    # push args
+    # . . push args
     68/push  "C"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # read(_test-stream, _test-stream-buffer)
-    # push args
+    # . . push args
     68/push  _test-stream-buffer/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  read/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(_test-stream, "D")
-    # push args
+    # . . push args
     68/push  "D"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # read(_test-stream, _test-stream-buffer)
-    # push args
+    # . . push args
     68/push  _test-stream-buffer/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  read/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(*_test-stream-buffer->data, 43/C 44/D 00 00, msg)
-    # push args
+    # . . push args
     68/push  "F - test-read-is-stateful"/imm32
     68/push  0x00004443/imm32/C-D
     # push *_test-stream-buffer->data
     b8/copy-to-EAX  _test-stream-buffer/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -297,53 +297,53 @@ test-read-is-stateful:
 test-read-returns-0-on-end-of-file:
     ## read after hitting end-of-file, check that result is 0
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-stream-buffer)
-    # push args
+    # . . push args
     68/push  _test-stream-buffer/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## first read gets to end-of-file
     # read(_test-stream, _test-stream-buffer)
-    # push args
+    # . . push args
     68/push  _test-stream-buffer/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  read/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## second read
     # read(_test-stream, _test-stream-buffer)
-    # push args
+    # . . push args
     68/push  _test-stream-buffer/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  read/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(EAX, 0)
-    # push args
+    # . . push args
     68/push  "F - test-read-returns-0-on-end-of-file"/imm32
     68/push  0/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -360,4 +360,4 @@ _test-stream-buffer:
     # data
     00 00 00 00 00 00 00 00  # 8 bytes
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/059read-byte.subx b/subx/059read-byte.subx
index da99eed3..39d818f4 100644
--- a/subx/059read-byte.subx
+++ b/subx/059read-byte.subx
@@ -27,9 +27,9 @@ Stdin:
 # TODO: 8 bytes is too small. We'll need to grow the buffer for efficiency.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
@@ -42,10 +42,10 @@ Stdin:
 # return next byte value in EAX, with top 3 bytes cleared.
 # On EOF, return 0xffffffff.
 read-byte:  # f : (address buffered-file) -> byte/EAX
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     56/push-ESI
     # ESI = f
@@ -56,20 +56,20 @@ read-byte:  # f : (address buffered-file) -> byte/EAX
     3b/compare                      1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # compare ECX with *(ESI+4)
     7c/jump-if-lesser  $read-byte:from-stream/disp8
     # clear-stream(stream = f+4)
-    # push args
+    # . . push args
     8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy ESI+4 to EAX
     50/push-EAX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # EAX = read(f->fd, stream = f+4)
-    # push args
+    # . . push args
     50/push-EAX
     ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
-    # call
+    # . . call
     e8/call  read/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # if EAX = 0 return 0xffffffff
     81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # compare EAX
@@ -83,10 +83,10 @@ $read-byte:from-stream:
     # ++f->read
     ff          0/subop/increment   1/mod/*+disp8   6/rm32/ESI    .           .             .           .           8/disp8         .                 # increment *(ESI+8)
 $read-byte:end:
-    # restore registers
+    # . restore registers
     5e/pop-to-ESI
     59/pop-to-ECX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -99,44 +99,44 @@ $read-byte:end:
 test-read-byte-single:
     ## check that read-byte returns first byte of 'file'
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-buffered-file+4)
-    # push args
+    # . . push args
     b8/copy-to-EAX  _test-buffered-file/imm32
     05/add-to-EAX  4/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # read-byte(_test-buffered-file)
-    # push args
+    # . . push args
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  read-byte/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # check-ints-equal(EAX, 'A')
-    # push args
+    # . . push args
     68/push  "F - test-read-byte-single"/imm32
     68/push  0x41/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -144,51 +144,51 @@ test-read-byte-single:
 test-read-byte-multiple:
     ## call read-byte twice, check that second call returns second byte
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-buffered-file+4)
-    # push args
+    # . . push args
     b8/copy-to-EAX  _test-buffered-file/imm32
     05/add-to-EAX  4/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # read-byte(_test-buffered-file)
-    # push args
+    # . . push args
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  read-byte/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # read-byte(_test-buffered-file)
-    # push args
+    # . . push args
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  read-byte/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # check-ints-equal(EAX, 'b')
-    # push args
+    # . . push args
     68/push  "F - test-read-byte-multiple"/imm32
     68/push  0x62/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -196,36 +196,36 @@ test-read-byte-multiple:
 test-read-byte-end-of-file:
     ## call read-byte on an empty 'file', check that it returns -1
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-buffered-file+4)
-    # push args
+    # . . push args
     b8/copy-to-EAX  _test-buffered-file/imm32
     05/add-to-EAX  4/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # read-byte(_test-buffered-file)
-    # push args
+    # . . push args
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  read-byte/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # check-ints-equal(EAX, -1)
-    # push args
+    # . . push args
     68/push  "F - test-read-byte-end-of-file"/imm32
     68/push  -1/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -244,4 +244,4 @@ _test-buffered-file:
     # data
     00 00 00 00 00 00 00 00  # 8 bytes
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/060write-stream.subx b/subx/060write-stream.subx
index 75957462..cf178bc1 100644
--- a/subx/060write-stream.subx
+++ b/subx/060write-stream.subx
@@ -1,9 +1,9 @@
 # write-stream: like write, but write streams rather than strings
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     # manual test
@@ -20,23 +20,23 @@
     cd/syscall  0x80/imm8
 
 write-stream:  # f : fd or (address stream), s : (address stream) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # if (f < 0x08000000) _write-stream(f, s), return  # f can't be a user-mode address, so treat it as a kernel file descriptor
     81          7/subop/compare     1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         0x08000000/imm32  # compare *(EBP+8)
     7d/jump-if-greater-or-equal  $write-stream:fake/disp8
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  _write-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     eb/jump  $write-stream:end/disp8
 $write-stream:fake:
     # otherwise, treat 'f' as a stream to append to
-    # save registers
+    # . save registers
     50/push-EAX
     56/push-ESI
     57/push-EDI
@@ -61,29 +61,29 @@ $write-stream:fake:
     8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+EAX+12 to EAX
     50/push-EAX
-    # call
+    # . . call
     e8/call  _append-4/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
     # f->write += EAX
     01/add                          0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # add EAX to *ESI
     # s->read += EAX
     01/add                          1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # add EAX to *(EDI+4)
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
     58/pop-to-EAX
 $write-stream:end:
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 _write-stream:  # fd : int, s : (address stream) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     52/push-EDX
@@ -106,120 +106,120 @@ _write-stream:  # fd : int, s : (address stream) -> <void>
     # syscall
     b8/copy-to-EAX  4/imm32/write
     cd/syscall  0x80/imm8
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 test-write-stream-single:
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-stream2)
-    # push args
+    # . . push args
     68/push  _test-stream2/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream2, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  _test-stream2/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write-stream(_test-stream, _test-stream2)
-    # push args
+    # . . push args
     68/push  _test-stream2/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(*_test-stream.data, 41/A 62/b 00 00, msg)
-    # push args
+    # . . push args
     68/push  "F - test-write-stream-single"/imm32
     68/push  0x006241/imm32/Ab
     # push *_test-stream.data
     b8/copy-to-EAX  _test-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
 
 test-write-stream-appends:
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-stream2)
-    # push args
+    # . . push args
     68/push  _test-stream2/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # write(_test-stream2, "C")
-    # push args
+    # . . push args
     68/push  "C"/imm32
     68/push  _test-stream2/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write-stream(_test-stream, _test-stream2)
-    # push args
+    # . . push args
     68/push  _test-stream2/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(_test-stream2, "D")
-    # push args
+    # . . push args
     68/push  "D"/imm32
     68/push  _test-stream2/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write-stream(_test-stream, _test-stream2)
-    # push args
+    # . . push args
     68/push  _test-stream2/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check-ints-equal(*_test-stream.data, 43/C 44/D 00 00, msg)
-    # push args
+    # . . push args
     68/push  "F - test-write-stream-appends"/imm32
     68/push  0x00004443/imm32/C-D
     # push *_test-stream.data
     b8/copy-to-EAX  _test-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
@@ -236,4 +236,4 @@ _test-stream2:
     # data
     41 42 43 44 00 00 00 00  # 8 bytes
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/apps/crenshaw2-1.subx b/subx/apps/crenshaw2-1.subx
index 94fd8efa..35966a22 100644
--- a/subx/apps/crenshaw2-1.subx
+++ b/subx/apps/crenshaw2-1.subx
@@ -26,12 +26,12 @@
 # naming conventions.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main: run tests if necessary, call 'compile' if not
-    # prolog
+    # . prolog
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # if (argc > 1)
     81          7/subop/compare     1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0/disp8         1/imm32           # compare *EBP
@@ -77,10 +77,10 @@ $main:end:
 
 # the main entry point
 compile:  # in : fd or (address stream), out : fd or (address stream), err : fd or (address stream), ed : (address exit-descriptor) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     # Look = get-char(in)
@@ -179,10 +179,10 @@ compile:  # in : fd or (address stream), out : fd or (address stream), err : fd
     e8/call  write/disp32
     # . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # restore registers
+    # . restore registers
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -211,7 +211,7 @@ get-num:  # in : (address buffered-file), out : (address stream), err : fd or (a
     # get-char in each iteration of the loop. (Thereby demonstrating that it's
     # not the right interface for us. But we'll keep it just to follow Crenshaw.)
     #
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # EAX = is-digit?(Look)
@@ -225,16 +225,16 @@ get-num:  # in : (address buffered-file), out : (address stream), err : fd or (a
     3d/compare-EAX  0/imm32
     75/jump-if-not-equal  $get-num:main/disp8
     # . expected(ed, err, "integer")
-      # push args
+    # . . push args
     68/push  "integer"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x10/disp8      .                 # push *(EBP+16)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x14/disp8      .                 # push *(EBP+20)
-      # call
+    # . . call
     e8/call  expected/disp32  # never returns
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
 $get-num:main:
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     52/push-EDX
@@ -254,13 +254,13 @@ $get-num:main:
     3b/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare EDX with ECX
     7d/jump-if-lesser  $get-num:stage2/disp8
     # error(ed, err, "get-num: too many digits in number")  # TODO: show full number
-      # . push args
+    # . push args
     68/push  "get-num: too many digits in number"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x10/disp8      .                 # push *(EBP+16)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x14/disp8      .                 # push *(EBP+20)
-      # . call
+    # . call
     e8/call  error/disp32  # never returns
-      # . discard args
+    # . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
 $get-num:stage2:
     # out->data[out->write] = LSB(Look)
@@ -279,14 +279,14 @@ $get-num:stage2:
 $get-num:loop-end:
     # persist necessary variables from registers
     89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EDI
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -475,7 +475,7 @@ test-get-num-aborts-on-non-digit-in-Look:
 
 # write(f, "Error: "+s+" expected\n") then stop(ed, 1)
 expected:  # ed : (address exit-descriptor), f : fd or (address stream), s : (address array byte) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # write(f, "Error: ")
@@ -517,14 +517,14 @@ expected:  # ed : (address exit-descriptor), f : fd or (address stream), s : (ad
     # . call
     e8/call  stop/disp32
     ## should never get past this point
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 # write(f, "Error: "+s+"\n") then stop(ed, 1)
 error:  # ed : (address exit-descriptor), f : fd or (address stream), s : (address array byte) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # write(f, "Error: ")
@@ -558,17 +558,17 @@ error:  # ed : (address exit-descriptor), f : fd or (address stream), s : (addre
     # . call
     e8/call  stop/disp32
     ## should never get past this point
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 # read a byte from 'f', and store it in 'Look'
 get-char:  # f : (address buffered-file) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     # read-byte(f)
     # . push args
@@ -579,15 +579,15 @@ get-char:  # f : (address buffered-file) -> <void>
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # save EAX to Look
     89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Look/disp32     .                 # copy EAX to *Look
-    # restore registers
+    # . restore registers
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 is-digit?:  # c : int -> bool/EAX
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # EAX = false
@@ -601,7 +601,7 @@ is-digit?:  # c : int -> bool/EAX
     # otherwise return true
     b8/copy-to-EAX  1/imm32
 $is-digit?:end:
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -631,4 +631,4 @@ _test-error-stream:
     # data
     00 00 00 00 00 00 00 00  # 8 bytes
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/apps/crenshaw2-1b.subx b/subx/apps/crenshaw2-1b.subx
index 2df45308..49436370 100644
--- a/subx/apps/crenshaw2-1b.subx
+++ b/subx/apps/crenshaw2-1b.subx
@@ -26,23 +26,23 @@
 # naming conventions.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main: run tests if necessary, call 'compile' if not
-    # prolog
+    # . prolog
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # if (argc > 1)
     81          7/subop/compare     1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0/disp8         1/imm32           # compare *EBP
     7e/jump-if-lesser-or-equal  $run-main/disp8
     # and if (argv[1] == "test")
-    # push args
+    # . . push args
     68/push  "test"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x8/disp8       .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check result
     3d/compare-EAX  1/imm32
@@ -60,14 +60,14 @@ $run-main:
     # clear ed->target (so we really exit)
     c7/copy                         0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
     # compile(Stdin, 1/stdout, 2/stderr, ed)
-    # push args
+    # . . push args
     50/push-EAX/ed
     68/push  2/imm32/stderr
     68/push  1/imm32/stdout
     68/push  Stdin/imm32
-    # call
+    # . . call
     e8/call  compile/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
     # syscall(exit, 0)
     bb/copy-to-EBX  0/imm32
@@ -77,18 +77,18 @@ $main:end:
 
 # the main entry point
 compile:  # in : fd or (address stream), out : fd or (address stream), err : fd or (address stream), ed : (address exit-descriptor) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     # Look = get-char(in)
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8      .                    # push *(EBP+8)
-    # call
+    # . . call
     e8/call  get-char/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # var num/ECX : (address stream) on the stack
     # Numbers can be 32 bits or 8 hex bytes long. One of them will be in 'Look', so we need space for 7 bytes.
@@ -99,90 +99,90 @@ compile:  # in : fd or (address stream), out : fd or (address stream), err : fd
     # num->length = 7
     c7/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           .           8/disp8         7/imm32           # copy to *(ECX+8)
     # clear-stream(num)
-    # push args
+    # . . push args
     51/push-ECX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # get-num(in, num, err, ed)
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x14/disp8      .                 # push *(EBP+20)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x10/disp8      .                 # push *(EBP+16)
     51/push-ECX/num
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8      .                    # push *(EBP+8)
-    # call
+    # . . call
     e8/call  get-num/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
     # EAX = write(_test-stream, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # EAX = write(out, "bb/copy-to-EBX  ")
-    # push args
+    # . . push args
     68/push  "bb/copy-to-EBX  "/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write-stream(out, num)
-    # push args
+    # . . push args
     51/push-ECX/num
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(out, Newline)
-    # push args
+    # . . push args
     68/push  Newline/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # EAX = write(out, "b8/copy-to-EAX  1/imm32/exit")
-    # push args
+    # . . push args
     68/push  "b8/copy-to-EAX  1/imm32/exit"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # EAX = write(out, Newline)
-    # push args
+    # . . push args
     68/push  Newline/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # EAX = write(out, "cd/syscall  0x80/imm8")
-    # push args
+    # . . push args
     68/push  "cd/syscall  0x80/imm8"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # EAX = write(out, Newline)
-    # push args
+    # . . push args
     68/push  Newline/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # restore registers
+    # . restore registers
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -216,30 +216,30 @@ get-num:  # in : (address buffered-file), out : (address stream), err : fd or (a
     # get-char in each iteration of the loop. (Thereby demonstrating that it's
     # not the right interface for us. But we'll keep it just to follow Crenshaw.)
     #
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # EAX = is-digit?(Look)
-    # push args
+    # . . push args
     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Look/disp32     .                 # push *Look
-    # call
+    # . . call
     e8/call  is-digit?/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # if EAX == 0 error
     3d/compare-EAX  0/imm32
     75/jump-if-not-equal  $get-num:main/disp8
     # expected(ed, err, "integer")
-      # push args
+    # . . push args
     68/push  "integer"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x10/disp8      .                 # push *(EBP+16)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x14/disp8      .                 # push *(EBP+20)
-      # call
+    # . . call
     e8/call  expected/disp32  # never returns
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
 $get-num:main:
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     52/push-EDX
@@ -260,13 +260,13 @@ $get-num:loop:
     3b/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare EDX with ECX
     7d/jump-if-lesser  $get-num:loop-stage2/disp8
     # error(ed, err, "get-num: too many digits in number")  # TODO: show full number
-      # push args
+    # . . push args
     68/push  "get-num: too many digits in number"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x10/disp8      .                 # push *(EBP+16)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x14/disp8      .                 # push *(EBP+20)
-      # call
+    # . . call
     e8/call  error/disp32  # never returns
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
 $get-num:loop-stage2:
     # out->data[out->write] = LSB(Look)
@@ -276,18 +276,18 @@ $get-num:loop-stage2:
     # ++out->write
     41/increment-ECX
     # Look = get-char(in)
-    # push args
+    # . . push args
     56/push-ESI
-    # call
+    # . . call
     e8/call  get-char/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # EAX = is-digit?(Look)
-    # push args
+    # . . push args
     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Look/disp32     .                 # push *Look
-    # call
+    # . . call
     e8/call  is-digit?/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # if EAX loop
     3d/compare-EAX  0/imm32
@@ -295,14 +295,14 @@ $get-num:loop-stage2:
 $get-num:loop-end:
     # persist necessary variables from registers
     89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EDI
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -314,43 +314,43 @@ test-get-num-reads-single-digit:
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     ## clear all streams
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-buffered-file+4)
-    # push args
+    # . . push args
     b8/copy-to-EAX  _test-buffered-file/imm32
     05/add-to-EAX  4/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-output-stream)
-    # push args
+    # . . push args
     68/push  _test-output-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-error-stream)
-    # push args
+    # . . push args
     68/push  _test-error-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     ## initialize 'in'
     # write(_test-stream, "3")
-    # push args
+    # . . push args
     68/push  "3"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## initialize exit-descriptor 'ed'
     # allocate on stack
@@ -359,41 +359,41 @@ test-get-num-reads-single-digit:
     8d/copy-address                 0/mod/indirect  4/rm32/sib    4/base/ESP  4/index/none  .           0/r32/EAX   .               .                 # copy ESP to EAX
     # size the exit-descriptor for the call to get-num below
     # tailor-exit-descriptor(ed, 16)
-    # push args
+    # . . push args
     68/push  0x10/imm32/nbytes-of-args-for-get-num
     50/push-EAX/ed
-    # call
+    # . . call
     e8/call  tailor-exit-descriptor/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## prime the pump
     # get-char(_test-buffered-file)
-    # push args
+    # . . push args
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  get-char/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     ## get-num(in, out, err, ed)
-    # push args
+    # . . push args
     50/push-EAX/ed
     68/push  _test-error-stream/imm32
     68/push  _test-output-stream/imm32
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  get-num/disp32
     ## registers except ESP may be clobbered at this point
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
     # check-ints-equal(*_test-output-stream.data, '3')
-    # push args
+    # . . push args
     68/push  "F - test-get-num-reads-single-digit"/imm32
     68/push  0x33/imm32
     b8/copy-to-EAX  _test-output-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # reclaim locals
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
@@ -407,43 +407,43 @@ test-get-num-aborts-on-non-digit-in-Look:
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     ## clear all streams
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-buffered-file+4)
-    # push args
+    # . . push args
     b8/copy-to-EAX  _test-buffered-file/imm32
     05/add-to-EAX  4/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-output-stream)
-    # push args
+    # . . push args
     68/push  _test-output-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-error-stream)
-    # push args
+    # . . push args
     68/push  _test-error-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     ## initialize 'in'
     # write(_test-stream, "3")
-    # push args
+    # . . push args
     68/push  "3"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## initialize exit-descriptor 'ed'
     # allocate on stack
@@ -452,35 +452,35 @@ test-get-num-aborts-on-non-digit-in-Look:
     8d/copy-address                 0/mod/indirect  4/rm32/sib    4/base/ESP  4/index/none  .           0/r32/EAX   .               .                 # copy ESP to EAX
     # size the exit-descriptor for the call to get-num below
     # tailor-exit-descriptor(ed, 16)
-    # push args
+    # . . push args
     68/push  0x10/imm32/nbytes-of-args-for-get-num
     50/push-EAX/ed
-    # call
+    # . . call
     e8/call  tailor-exit-descriptor/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## don't initialize Look
     ## get-num(in, out, err, ed)
-    # push args
+    # . . push args
     50/push-EAX/ed
     68/push  _test-error-stream/imm32
     68/push  _test-output-stream/imm32
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  get-num/disp32
     ## registers except ESP may be clobbered at this point
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
     ## check that get-num tried to call exit(1)
     # check-ints-equal(ed->value, 2, msg)  # i.e. stop was called with value 1
-    # push args
+    # . . push args
     68/push  "F - test-get-num-aborts-on-non-digit-in-Look"/imm32
     68/push  2/imm32
     # push ed->value
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # reclaim locals
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
@@ -494,43 +494,43 @@ test-get-num-reads-multiple-digits:
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     ## clear all streams
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-buffered-file+4)
-    # push args
+    # . . push args
     b8/copy-to-EAX  _test-buffered-file/imm32
     05/add-to-EAX  4/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-output-stream)
-    # push args
+    # . . push args
     68/push  _test-output-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-error-stream)
-    # push args
+    # . . push args
     68/push  _test-error-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     ## initialize 'in'
     # write(_test-stream, "3456 x")
-    # push args
+    # . . push args
     68/push  "3456"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## initialize exit-descriptor 'ed'
     # allocate on stack
@@ -539,41 +539,41 @@ test-get-num-reads-multiple-digits:
     8d/copy-address                 0/mod/indirect  4/rm32/sib    4/base/ESP  4/index/none  .           0/r32/EAX   .               .                 # copy ESP to EAX
     # size the exit-descriptor for the call to get-num below
     # tailor-exit-descriptor(ed, 16)
-    # push args
+    # . . push args
     68/push  0x10/imm32/nbytes-of-args-for-get-num
     50/push-EAX/ed
-    # call
+    # . . call
     e8/call  tailor-exit-descriptor/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## prime the pump
     # get-char(_test-buffered-file)
-    # push args
+    # . . push args
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  get-char/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     ## get-num(in, out, err, ed)
-    # push args
+    # . . push args
     50/push-EAX/ed
     68/push  _test-error-stream/imm32
     68/push  _test-output-stream/imm32
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  get-num/disp32
     ## registers except ESP may be clobbered at this point
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
     # check-ints-equal(*_test-output-stream.data, '3456')
-    # push args
+    # . . push args
     68/push  "F - test-get-num-reads-multiple-digits"/imm32
     68/push  0x36353433/imm32
     b8/copy-to-EAX  _test-output-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # reclaim locals
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
@@ -587,43 +587,43 @@ test-get-num-reads-multiple-digits-followed-by-nondigit:
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     ## clear all streams
     # clear-stream(_test-stream)
-    # push args
+    # . . push args
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-buffered-file+4)
-    # push args
+    # . . push args
     b8/copy-to-EAX  _test-buffered-file/imm32
     05/add-to-EAX  4/imm32
     50/push-EAX
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-output-stream)
-    # push args
+    # . . push args
     68/push  _test-output-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # clear-stream(_test-error-stream)
-    # push args
+    # . . push args
     68/push  _test-error-stream/imm32
-    # call
+    # . . call
     e8/call  clear-stream/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     ## initialize 'in'
     # write(_test-stream, "3456 x")
-    # push args
+    # . . push args
     68/push  "3456 x"/imm32
     68/push  _test-stream/imm32
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## initialize exit-descriptor 'ed'
     # allocate on stack
@@ -632,41 +632,41 @@ test-get-num-reads-multiple-digits-followed-by-nondigit:
     8d/copy-address                 0/mod/indirect  4/rm32/sib    4/base/ESP  4/index/none  .           0/r32/EAX   .               .                 # copy ESP to EAX
     # size the exit-descriptor for the call to get-num below
     # tailor-exit-descriptor(ed, 16)
-    # push args
+    # . . push args
     68/push  0x10/imm32/nbytes-of-args-for-get-num
     50/push-EAX/ed
-    # call
+    # . . call
     e8/call  tailor-exit-descriptor/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     ## prime the pump
     # get-char(_test-buffered-file)
-    # push args
+    # . . push args
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  get-char/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     ## get-num(in, out, err, ed)
-    # push args
+    # . . push args
     50/push-EAX/ed
     68/push  _test-error-stream/imm32
     68/push  _test-output-stream/imm32
     68/push  _test-buffered-file/imm32
-    # call
+    # . . call
     e8/call  get-num/disp32
     ## registers except ESP may be clobbered at this point
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
     # check-ints-equal(*_test-output-stream.data, '3456')
-    # push args
+    # . . push args
     68/push  "F - test-get-num-reads-multiple-digits-followed-by-nondigit"/imm32
     68/push  0x36353433/imm32
     b8/copy-to-EAX  _test-output-stream/imm32
     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # reclaim locals
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
@@ -677,119 +677,119 @@ test-get-num-reads-multiple-digits-followed-by-nondigit:
 
 # write(f, "Error: "+s+" expected\n") then stop(ed, 1)
 expected:  # ed : (address exit-descriptor), f : fd or (address stream), s : (address array byte) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # write(f, "Error: ")
-    # push args
+    # . . push args
     68/push  "Error: "/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(f, s)
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x10/disp8      .                 # push *(EBP+16)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(f, " expected")
-    # push args
+    # . . push args
     68/push  " expected"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(f, Newline)
-    # push args
+    # . . push args
     68/push  Newline/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # stop(ed, 1)
-    # push args
+    # . . push args
     68/push  1/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  stop/disp32
     ## should never get past this point
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 # write(f, "Error: "+s+"\n") then stop(ed, 1)
 error:  # ed : (address exit-descriptor), f : fd or (address stream), s : (address array byte) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # write(f, "Error: ")
-    # push args
+    # . . push args
     68/push  "Error: "/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(f, s)
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x10/disp8      .                 # push *(EBP+16)
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # write(f, Newline)
-    # push args
+    # . . push args
     68/push  Newline/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
-    # call
+    # . . call
     e8/call  write/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # stop(ed, 1)
-    # push args
+    # . . push args
     68/push  1/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           8/disp8         .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  stop/disp32
     ## should never get past this point
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 # read a byte from 'f', and store it in 'Look'
 get-char:  # f : (address buffered-file) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     # read-byte(f)
-    # push args
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x8/disp8       .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  read-byte/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # save EAX to Look
     89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Look/disp32     .                 # copy EAX to *Look
-    # restore registers
+    # . restore registers
     58/pop-to-EAX
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
 
 is-digit?:  # c : int -> bool/EAX
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # EAX = false
@@ -803,7 +803,7 @@ is-digit?:  # c : int -> bool/EAX
     # otherwise return true
     b8/copy-to-EAX  1/imm32
 $is-digit?:end:
-    # epilog
+    # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
     c3/return
@@ -833,4 +833,4 @@ _test-error-stream:
     # data
     00 00 00 00 00 00 00 00  # 8 bytes
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/apps/factorial.subx b/subx/apps/factorial.subx
index 1e0191d1..f7675962 100644
--- a/subx/apps/factorial.subx
+++ b/subx/apps/factorial.subx
@@ -15,23 +15,23 @@
 # When running tests the exit status doesn't mean anything. Yet.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
-    # prolog
+    # . prolog
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # if (argc > 1)
     81          7/subop/compare     1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0/disp8         1/imm32           # compare *EBP
     7e/jump-if-lesser-or-equal  $run-main/disp8
     # and if (argv[1] == "test")
-    # push args
+    # . . push args
     68/push  "test"/imm32
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x8/disp8       .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # check result
     3d/compare-EAX  1/imm32
@@ -42,11 +42,11 @@
     eb/jump  $main:end/disp8  # where EAX will get copied to EBX
     # else EAX = factorial(5)
 $run-main:
-    # push args
+    # . . push args
     68/push  5/imm32
-    # call
+    # . . call
     e8/call  factorial/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
 $main:end:
     # exit(EAX)
@@ -56,7 +56,7 @@ $main:end:
 
 # factorial(n)
 factorial:
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     53/push-EBX
@@ -69,17 +69,17 @@ factorial:
     8b/copy                         1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none              3/r32/EBX   8/disp8         .                 # copy *(EBP+8) to EBX
     81          5/subop/subtract    3/mod/direct    3/rm32/EBX    .           .             .           .           .               1/imm32           # subtract from EBX
     # EAX = factorial(n-1)
-    # push args
+    # . . push args
     53/push-EBX
-    # call
+    # . . call
     e8/call  factorial/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # return n * factorial(n-1)
     f7          4/subop/multiply    1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none                          8/disp8         .                 # multiply *(EBP+8) into EAX
     # TODO: check for overflow
 $factorial:end:
-    # epilog
+    # . epilog
     5b/pop-to-EBX
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
@@ -87,22 +87,22 @@ $factorial:end:
 
 test-factorial:
     # factorial(5)
-    # push args
+    # . . push args
     68/push  5/imm32
-    # call
+    # . . call
     e8/call  factorial/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # check-ints-equal(EAX, 120, failure message)
-    # push args
+    # . . push args
     68/push  "F - test-factorial"/imm32
     68/push  0x78/imm32/expected-120
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     # end
     c3/return
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex1.subx b/subx/examples/ex1.subx
index 8bef59e7..3371cd75 100644
--- a/subx/examples/ex1.subx
+++ b/subx/examples/ex1.subx
@@ -15,4 +15,4 @@ bb/copy-to-EBX  2a/imm32  # 42 in hex
 b8/copy-to-EAX  1/imm32/exit
 cd/syscall  0x80/imm8
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex10.subx b/subx/examples/ex10.subx
index 4da713ae..936edb08 100644
--- a/subx/examples/ex10.subx
+++ b/subx/examples/ex10.subx
@@ -8,9 +8,9 @@
 #   0  # false
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main: return argv-equal(argv[1], argv[2])
 #       At the start of a SubX program:
@@ -18,14 +18,14 @@
 #         argv[0]: *(ESP+4)
 #         argv[1]: *(ESP+8)
 #         ...
-    # prolog
+    # . prolog
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # call argv-equal(argv[1], argv[2])
+    # . . call argv-equal(argv[1], argv[2])
     # push argv[2]
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
     # push argv[1]
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x8/disp8       .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call argv-equal/disp32
     # exit(EAX)
 $exit:
@@ -69,4 +69,4 @@ $argv-equal:false:
     b8/copy-to-EAX  0/imm32
     c3/return
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex11.subx b/subx/examples/ex11.subx
index 247a0076..253b91ab 100644
--- a/subx/examples/ex11.subx
+++ b/subx/examples/ex11.subx
@@ -15,9 +15,9 @@
 # would cause tests to not run, rather than to fail as we'd like.)
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
@@ -29,10 +29,10 @@
 # compare a null-terminated ascii string with a more idiomatic length-prefixed byte array
 # reason for the name: the only place we should have null-terminated ascii strings is from commandline args
 kernel-string-equal:  # s : null-terminated ascii string, benchmark : length-prefixed ascii string -> EAX : boolean
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     52/push-EDX
     53/push-EBX
@@ -97,7 +97,7 @@ $kernel-string-equal:false:
     b8/copy-to-EAX  0/imm32
 
 $kernel-string-equal:end:
-    # restore registers
+    # . restore registers
     5f/pop-to-EDI
     5e/pop-to-ESI
     5b/pop-to-EBX
@@ -112,141 +112,141 @@ $kernel-string-equal:end:
 
 test-compare-null-kernel-string-with-empty-array:
     # EAX = kernel-string-equal(Null-kernel-string, "")
-    # push args
+    # . . push args
     68/push  ""/imm32
     68/push  Null-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 1, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 1, msg)
+    # . . push args
     68/push  "F - test-compare-null-kernel-string-with-empty-array"/imm32
     68/push  1/imm32/true
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-null-kernel-string-with-non-empty-array:
     # EAX = kernel-string-equal(Null-kernel-string, "Abc")
-    # push args
+    # . . push args
     68/push  "Abc"/imm32
     68/push  Null-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 0, msg)
+    # . . push args
     68/push  "F - test-compare-null-kernel-string-with-non-empty-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-equal-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "Abc")
-    # push args
+    # . . push args
     68/push  "Abc"/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 1, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 1, msg)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-equal-array"/imm32
     68/push  1/imm32/true
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-inequal-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "Adc")
-    # push args
+    # . . push args
     68/push  "Adc"/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0, msg)
-    # push args
+    # . . call check-ints-equal(EAX, 0, msg)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-equal-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-empty-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "")
-    # push args
+    # . . push args
     68/push  ""/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0)
-    # push args
+    # . . call check-ints-equal(EAX, 0)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-equal-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-shorter-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "Ab")
-    # push args
+    # . . push args
     68/push  "Ab"/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0)
-    # push args
+    # . . call check-ints-equal(EAX, 0)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-shorter-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
 test-compare-kernel-string-with-longer-array:
     # EAX = kernel-string-equal(Abc-kernel-string, "Abcd")
-    # push args
+    # . . push args
     68/push  "Abcd"/imm32
     68/push  Abc-kernel-string/imm32
-    # call
+    # . . call
     e8/call  kernel-string-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
-    # call check-ints-equal(EAX, 0)
-    # push args
+    # . . call check-ints-equal(EAX, 0)
+    # . . push args
     68/push  "F - test-compare-kernel-string-with-longer-array"/imm32
     68/push  0/imm32/false
     50/push-EAX
-    # call
+    # . . call
     e8/call  check-ints-equal/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
@@ -254,10 +254,10 @@ test-compare-kernel-string-with-longer-array:
 
 # print msg to stderr if a != b, otherwise print "."
 check-ints-equal:  # (a : int, b : int, msg : (address array byte)) -> boolean
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     51/push-ECX
     53/push-EBX
     # load args into EAX, EBX and ECX
@@ -267,11 +267,11 @@ check-ints-equal:  # (a : int, b : int, msg : (address array byte)) -> boolean
     39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # compare EAX and EBX
     75/jump-if-unequal  $check-ints-equal:else/disp8
     # print('.')
-      # push args
+    # . . push args
     68/push  "."/imm32
-      # call
+    # . . call
     e8/call  write-stderr/disp32
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # return
     eb/jump  $check-ints-equal:end/disp8
@@ -280,21 +280,21 @@ $check-ints-equal:else:
     # copy msg into ECX
     8b/copy                         1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           1/r32/ECX   0x10/disp8       .                # copy *(EBP+16) to ECX
     # print(ECX)
-      # push args
+    # . . push args
     51/push-ECX
-      # call
+    # . . call
     e8/call  write-stderr/disp32
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # print newline
-      # push args
+    # . . push args
     68/push  Newline/imm32
-      # call
+    # . . call
     e8/call  write-stderr/disp32
-      # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
 $check-ints-equal:end:
-    # restore registers
+    # . restore registers
     5b/pop-to-EBX
     59/pop-to-ECX
     # end
@@ -303,10 +303,10 @@ $check-ints-equal:end:
     c3/return
 
 write-stderr:  # s : (address array byte) -> <void>
-    # prolog
+    # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # save registers
+    # . save registers
     50/push-EAX
     51/push-ECX
     52/push-EDX
@@ -323,7 +323,7 @@ write-stderr:  # s : (address array byte) -> <void>
     # syscall
     b8/copy-to-EAX  4/imm32/write
     cd/syscall  0x80/imm8
-    # restore registers
+    # . restore registers
     5b/pop-to-EBX
     5a/pop-to-EDX
     59/pop-to-ECX
@@ -347,4 +347,4 @@ Null-kernel-string:
 Abc-kernel-string:
     41/A 62/b 63/c 00/null
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex12.subx b/subx/examples/ex12.subx
index 73d78d96..565c8d50 100644
--- a/subx/examples/ex12.subx
+++ b/subx/examples/ex12.subx
@@ -7,9 +7,9 @@
 # You shouldn't get a segmentation fault.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
     # syscall(mmap, 0x1000)
     bb/copy-to-EBX  Mmap-new-segment/imm32
@@ -41,4 +41,4 @@ Mmap-new-segment:  # type mmap_arg_struct
     # offset
     00 00 00 00  # 0 since MAP_ANONYMOUS is specified
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex2.subx b/subx/examples/ex2.subx
index 09fe4414..f7be9b65 100644
--- a/subx/examples/ex2.subx
+++ b/subx/examples/ex2.subx
@@ -15,4 +15,4 @@ bb/copy-to-EBX  1/imm32
 b8/copy-to-EAX  1/imm32
 cd/syscall  0x80/imm8
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex3.subx b/subx/examples/ex3.subx
index b3f7d6fe..b6e21698 100644
--- a/subx/examples/ex3.subx
+++ b/subx/examples/ex3.subx
@@ -8,9 +8,9 @@
 #   55
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
     # result: EBX = 0
     bb/copy-to-EBX  0/imm32
@@ -33,4 +33,4 @@ $exit:
     b8/copy-to-EAX  1/imm32
     cd/syscall  0x80/imm8
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex4.subx b/subx/examples/ex4.subx
index 445f7d1b..2fd15cd7 100644
--- a/subx/examples/ex4.subx
+++ b/subx/examples/ex4.subx
@@ -37,4 +37,4 @@ cd/syscall  0x80/imm8
 X:
     00 00 00 00  # space for read() to write to
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex5.subx b/subx/examples/ex5.subx
index 44291b35..136c177b 100644
--- a/subx/examples/ex5.subx
+++ b/subx/examples/ex5.subx
@@ -5,9 +5,9 @@
 #   $ subx run examples/ex5
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
 # main:
     # allocate x on the stack
@@ -39,4 +39,4 @@
     b8/copy-to-EAX  1/imm32/exit
     cd/syscall  0x80/imm8
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex6.subx b/subx/examples/ex6.subx
index 10331808..fc266a3a 100644
--- a/subx/examples/ex6.subx
+++ b/subx/examples/ex6.subx
@@ -6,9 +6,9 @@
 #   Hello, world!
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
     # syscall(write, stdout, X, size)
     # fd = 1 (stdout)
@@ -33,4 +33,4 @@ X:  # string to print
     48 65 6c 6c 6f 2c 20 77 6f 72 6c 64 21 0a       00
 # H  e  l  l  o  ,  ␣  w  o  r  l  d  !  newline  null
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex7.subx b/subx/examples/ex7.subx
index 93b568f9..3650817d 100644
--- a/subx/examples/ex7.subx
+++ b/subx/examples/ex7.subx
@@ -11,9 +11,9 @@
 #   97
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
     # syscall(creat, Filename)
     bb/copy-to-EBX  Filename/imm32
@@ -101,4 +101,4 @@ B:
 Filename:
     2e 66 6f 6f 00 00 00 00
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex8.subx b/subx/examples/ex8.subx
index fd7929f4..410dfe08 100644
--- a/subx/examples/ex8.subx
+++ b/subx/examples/ex8.subx
@@ -15,18 +15,18 @@
 # Locals start from ESP-4 downwards.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
-    # prolog
+    # . prolog
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # call ascii-length(argv[1])
-    # push args
+    # . . call ascii-length(argv[1])
+    # . . push args
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x8/disp8       .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  ascii-length/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
 
     # exit(EAX)
@@ -55,4 +55,4 @@ $ascii-length-ret:
     # return (result in EAX)
     c3/return
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0
diff --git a/subx/examples/ex9.subx b/subx/examples/ex9.subx
index 00f2d661..964151a2 100644
--- a/subx/examples/ex9.subx
+++ b/subx/examples/ex9.subx
@@ -17,20 +17,20 @@
 # Locals start from ESP-4 downwards.
 
 == code
-#   instruction                     effective address                                                   operand     displacement    immediate
-#   op          subop               mod             rm32          base        index         scale       r32
-#   1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
 
-    # prolog
+    # . prolog
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # call ascii-difference(argv[1], argv[2])
+    # . . call ascii-difference(argv[1], argv[2])
     # push argv[2]
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0xc/disp8       .                 # push *(EBP+12)
     # push argv[1]
     ff          6/subop/push        1/mod/*+disp8   4/rm32/sib    5/base/EBP  4/index/none  .           .           0x8/disp8       .                 # push *(EBP+8)
-    # call
+    # . . call
     e8/call  ascii-difference/disp32
-    # discard args
+    # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
     # exit(EAX)
     89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EBX
@@ -48,4 +48,4 @@ ascii-difference:  # (s1, s2) : null-terminated ascii strings
     29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
     c3/return
 
-# vim:nowrap:textwidth=0
+# . . vim:nowrap:textwidth=0