initial draft of solution for 'compute-addresses'

No trace statements yet, so we don't know if it works.

6 files changed, 331 insertions, 15 deletions

diff --git a/subx/apps/assort b/subx/apps/assort
index 188fc4b4..f35c0d85 100755
--- a/subx/apps/assort
+++ b/subx/apps/assort
Binary files differdiff --git a/subx/apps/assort.subx b/subx/apps/assort.subx
index 2f9ca98e..55f0c9a8 100644
--- a/subx/apps/assort.subx
+++ b/subx/apps/assort.subx
@@ -667,9 +667,9 @@ $read-segments:check-for-segment-header:
 #?     # . . discard args
 #?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
 #?     # }}}
-    # segment-slot/EAX = get-or-insert-slice(table, segment-name, value-size=8)
+    # segment-slot/EAX = get-or-insert-slice(table, segment-name, row-size=8)
     # . . push args
-    68/push  8/imm32/value-size
+    68/push  8/imm32/row-size
     52/push-EDX
     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
     # . . call
diff --git a/subx/apps/pack b/subx/apps/pack
index d90d266a..e50a6843 100755
--- a/subx/apps/pack
+++ b/subx/apps/pack
Binary files differdiff --git a/subx/apps/subx-common.subx b/subx/apps/subx-common.subx
index 4555d75e..ca0fa943 100644
--- a/subx/apps/subx-common.subx
+++ b/subx/apps/subx-common.subx
@@ -8,21 +8,268 @@
 # 'table' is a stream of (key, value) rows
 # keys are always strings (addresses; size 4 bytes)
 # values may be any type, but rows (key+value) always occupy 'row-size' bytes
-# scan 'table' for a row with a key 's' and return the address of the corresponding value
-# if no row is found, save 's' in the next available row
+# scan 'table' for a row with a key 'key' and return the address of the corresponding value
+# if no row is found, save 'key' to the next available row
 # if there are no rows free, abort
+# return the address of the value
+# Beware: assume keys are immutable; they're inserted by reference
 # TODO: pass in an allocation descriptor
-get-or-insert-slice:  # table : (address stream {string, _}), s : (address slice), row-size : int -> EAX : (address _)
+get-or-insert:  # table : (address stream {string, _}), key : (address string), row-size : int -> EAX : (address _)
     # pseudocode:
     #   curr = table->data
     #   max = &table->data[table->write]
     #   while curr < max
-    #     if slice-equal?(s, *curr)
+    #     if string-equal?(key, *curr)
     #       return curr+4
     #     curr += row-size
     #   if table->write >= table->length
     #     abort
-    #   *max = slice-to-string(Heap, s)
+    #   *max = key
+    #   table->write += row-size
+    #   return max+4
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    # ESI = table
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # curr/ECX = table->data
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   0xc/disp8       .                 # copy ESI+12 to ECX
+    # max/EDX = table->data + table->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
+    8d/copy-address                 0/mod/indirect  4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   .               .                 # copy ECX+EDX to EDX
+$get-or-insert:search-loop:
+    # if (curr >= max) break
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    7d/jump-if-greater-or-equal  $get-or-insert:not-found/disp8
+    # if (string-equal?(key, *curr)) return *(curr+4)
+    # . EAX = string-equal?(key, *curr)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return EAX = curr+4
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $get-or-insert:mismatch/disp8
+    8d/copy-address                 1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy ECX+4 to EAX
+    eb/jump  $get-or-insert:end/disp8
+$get-or-insert:mismatch:
+    # curr += row-size
+    03/add                          1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0x10/disp8      .                 # add *(EBP+16) to ECX
+    # loop
+    eb/jump  $get-or-insert:search-loop/disp8
+$get-or-insert:not-found:
+    # result/EAX = 0
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    # if (table->write >= table->length) abort
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    3b/compare                      1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   8/disp8         .                 # compare ECX with *(ESI+8)
+    7d/jump-if-greater-or-equal  $get-or-insert:abort/disp8
+    # *max = key
+    # . EAX = key
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy *(EBP+12) to EAX
+    # . *max = EAX
+    89/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDX
+    # table->write += row-size
+    # . EAX = row-size
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0x10/disp8      .                 # copy *(EBP+16) to EAX
+    # . table->write += EAX
+    01/add                          0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # add EAX to *ESI
+    # return max+4
+    # . EAX = max
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy EDX to EAX
+    # . EAX += 4
+    05/add-to-EAX  4/imm32
+$get-or-insert:end:
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+$get-or-insert:abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "get-or-insert: too many segments"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+test-get-or-insert:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # var table/ECX : (address stream {string, number}) = stream(2 rows * 8 bytes)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # subtract from ESP
+    68/push  0x10/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+$test-get-or-insert:first-call:
+    # - start with an empty table, insert one key, verify that it was inserted
+    # EAX = get-or-insert(table, "code", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "code"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 4, msg)  # first row's value slot returned
+    # . check-ints-equal(EAX - table, 16, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/0"/imm32
+    68/push  0x10/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-or-insert:check2:
+    # check-ints-equal(table->write, row-size = 8, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/1"/imm32
+    68/push  8/imm32/row-size
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data, "code", msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/2"/imm32
+    68/push  "code"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-or-insert:second-call:
+    # - insert the same key again, verify that it was reused
+    # EAX = get-or-insert(table, "code", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "code"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 4, msg)
+    # . check-ints-equal(EAX - table, 16, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/3"/imm32
+    68/push  0x10/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # no new row inserted
+    # . check-ints-equal(table->write, row-size = 8, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/4"/imm32
+    68/push  8/imm32/row-size
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data, "code", msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/5"/imm32
+    68/push  "code"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-or-insert:third-call:
+    # - insert a new key, verify that it was inserted
+    # EAX = get-or-insert(table, "data", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "data"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # table gets a new row
+    # check-ints-equal(EAX - table->data, 12, msg)  # second row's value slot returned
+    # . check-ints-equal(EAX - table, 24, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/6"/imm32
+    68/push  0x18/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(table->write, 2 rows = 16, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/7"/imm32
+    68/push  0x10/imm32/two-rows
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data+8, "data", msg)
+    # check-string-equal(*(table+20), "data", msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/8"/imm32
+    68/push  "data"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0x14/disp8      .                 # push *(ECX+20)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-or-insert:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# 'table' is a stream of (key, value) rows
+# keys are always strings (addresses; size 4 bytes)
+# values may be any type, but rows (key+value) always occupy 'row-size' bytes
+# scan 'table' for a row with a key 'key' and return the address of the corresponding value
+# if no row is found, save 'key' in the next available row
+# if there are no rows free, abort
+# TODO: pass in an allocation descriptor
+get-or-insert-slice:  # table : (address stream {string, _}), key : (address slice), row-size : int -> EAX : (address _)
+    # pseudocode:
+    #   curr = table->data
+    #   max = &table->data[table->write]
+    #   while curr < max
+    #     if slice-equal?(key, *curr)
+    #       return curr+4
+    #     curr += row-size
+    #   if table->write >= table->length
+    #     abort
+    #   *max = slice-to-string(Heap, key)
     #   table->write += row-size
     #   return max+4
     #
@@ -44,8 +291,8 @@ $get-or-insert-slice:search-loop:
     # if (curr >= max) break
     39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
     7d/jump-if-greater-or-equal  $get-or-insert-slice:not-found/disp8
-    # if (slice-equal?(s, *curr)) return *(curr+4)
-    # . EAX = slice-equal?(s, *curr)
+    # if (slice-equal?(key, *curr)) return *(curr+4)
+    # . EAX = slice-equal?(key, *curr)
     # . . push args
     ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
@@ -70,8 +317,8 @@ $get-or-insert-slice:not-found:
     8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
     3b/compare                      1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   8/disp8         .                 # compare ECX with *(ESI+8)
     7d/jump-if-greater-or-equal  $get-or-insert-slice:abort/disp8
-    # *max = slice-to-string(Heap, s)
-    # . EAX = slice-to-string(Heap, s)
+    # *max = slice-to-string(Heap, key)
+    # . EAX = slice-to-string(Heap, key)
     # . . push args
     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
     68/push  Heap/imm32
diff --git a/subx/apps/survey b/subx/apps/survey
index dedf6a9b..e1d3185d 100755
--- a/subx/apps/survey
+++ b/subx/apps/survey
Binary files differdiff --git a/subx/apps/survey.subx b/subx/apps/survey.subx
index a73bb661..579dfbad 100644
--- a/subx/apps/survey.subx
+++ b/subx/apps/survey.subx
@@ -545,22 +545,91 @@ compute-addresses:  # segments : (address stream {string, segment-info}), labels
     #     if (s >= max) break
     #     s->address &= 0xfffff000  # clear last 12 bits for p_align
     #     s->address += (s->file-offset & 0x00000fff)
-    #     s += 16  # size of segment-info
+    #     s += 16  # size of row
     #   l : (address label-info) = labels->data + 4  # skip key
     #   max = labels->data + labels->write
     #   while true
     #     if (l >= max) break
     #     seg-name : (address string) = l->segment-name
-    #     label-seg : (address segment-info) = get(labels, seg-name)
+    #     label-seg : (address segment-info) = get-or-insert(segments, seg-name)
     #     l->address = label-seg->address + l->segment-offset
+    #     l += 16  # size of row
     #
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
     # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    # ESI = segments
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # s/EAX = segments->data + 4
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy ESI+16 to EAX
+    # max/ECX = segments->data + segments->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    01/add                          3/mod/direct    1/rm32/ECX    .           .             .           6/r32/ESI   .               .                 # add ESI to ECX
+$compute-addresses:segment-loop:
+    # if (s >= max) break
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # compare EAX with ECX
+    73/jump-if-greater-or-equal-unsigned  $compute-addresses:segment-break/disp8
+    # clear last 12 bits of s->address for p_align=0x1000
+    # . EDX = s->address
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy *EAX to EDX
+    # . EDX &= 0xfffff000
+    81          4/subop/and         3/mod/direct    2/rm32/EDX    .           .             .           .           .               0xfffff000/imm32  # bitwise and of EDX
+    # update last 12 bits from s->file-offset
+    # . EBX = s->file-offset
+    8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           3/r32/EBX   4/disp8         .                 # copy *(EAX+4) to EBX
+    # . EBX &= 0xfff
+    81          4/subop/and         3/mod/direct    3/rm32/EBX    .           .             .           .           .               0x00000fff/imm32  # bitwise and of EBX
+    # . s->address = EDX | EBX
+    09/or                           3/mod/direct    2/rm32/EDX    .           .             .           3/r32/EBX   .               .                 # EDX = bitwise OR with EBX
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy EDX to *EAX
+    # s += 16  # size of row
+    05/add-to-EAX  0x10/imm32
+    eb/jump  $compute-addresses:segment-loop/disp8
+$compute-addresses:segment-break:
+    # ESI = labels
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+    # l/EAX = labels->data + 4
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy ESI+16 to EAX
+    # max/ECX = labels->data + labels->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    01/add                          3/mod/direct    1/rm32/ECX    .           .             .           6/r32/ESI   .               .                 # add ESI to ECX
+$compute-addresses:label-loop:
+    # if (l >= max) break
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # compare EAX with ECX
+    73/jump-if-greater-or-equal-unsigned  $compute-addresses:end/disp8
+    # seg-name/EDX = l->segment-name
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy *EAX to EDX
+    # label-seg/EDX : (address label-info) = get-or-insert(labels, seg-name, row-size=16)
+    # . . push args
+    68/push  0x10/imm32/row-size
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # EBX = label-seg->address
+    8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           3/r32/EBX   .               .                 # copy *EDX to EBX
+    # EBX += l->segment-offset
+    03/add                          1/mod/*+disp8   5/rm32/EBP    .           .             .           3/r32/EBX   4/disp8         .                 # add *(EAX+4) to EBX
+    # l->address = EBX
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # copy EBX to *EAX
+    # l += 16  # size of row
+    05/add-to-EAX  0x10/imm32
+    eb/jump  $compute-addresses:label-loop/disp8
 $compute-addresses:end:
-    # . reclaim locals
     # . restore registers
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
     # . epilog
     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
     5d/pop-to-EBP
@@ -696,7 +765,7 @@ stream-add4:  # in : (address stream byte), key : address, val1 : address, val2
     52/push-EDX
     56/push-ESI
     # ESI = in
-    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
     # curr/EAX = in->data + in->write
     # . EAX = in->write
     8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX