5856

25 files changed, 0 insertions, 872 deletions

diff --git a/examples/Readme.md b/examples/Readme.md
deleted file mode 100644
index d4bb1ff5..00000000
--- a/examples/Readme.md
+++ /dev/null
@@ -1,6 +0,0 @@
-Small example programs, each with a simple pedagogical goal.
-
-They also help to validate SubX instruction semantics against native x86
-hardware. For example, loading a single byte to a register would for some time
-clear the rest of the register. This behavior was internally consistent with
-unit tests. It took running an example binary natively to catch the discrepancy.
diff --git a/examples/ex1 b/examples/ex1
deleted file mode 100755
index 5f17bc66..00000000
--- a/examples/ex1
+++ /dev/null
Binary files differdiff --git a/examples/ex1.subx b/examples/ex1.subx
deleted file mode 100644
index 5558d310..00000000
--- a/examples/ex1.subx
+++ /dev/null
@@ -1,18 +0,0 @@
-# First program: same as https://www.muppetlabs.com/~breadbox/software/tiny/teensy.html
-# Just return 42.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex1.2.subx -o examples/ex1
-#   $ ./subx run examples/ex1
-# Expected result:
-#   $ echo $?
-#   42
-
-== code
-
-Entry:
-# exit(42)
-bb/copy-to-ebx  2a/imm32  # 42 in hex
-e8/call  syscall_exit/disp32
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex10 b/examples/ex10
deleted file mode 100755
index cb8973fe..00000000
--- a/examples/ex10
+++ /dev/null
Binary files differdiff --git a/examples/ex10.subx b/examples/ex10.subx
deleted file mode 100644
index c091fe52..00000000
--- a/examples/ex10.subx
+++ /dev/null
@@ -1,69 +0,0 @@
-# String comparison: return 1 iff the two args passed in at the commandline are equal.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex10.subx -o examples/ex10
-#   $ ./subx run examples/ex10 abc abd
-# Expected result:
-#   $ echo $?
-#   0  # false
-
-== code
-#   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
-
-Entry:  # return argv-equal(argv[1], argv[2])
-#       At the start of a SubX program:
-#         argc: *esp
-#         argv[0]: *(esp+4)
-#         argv[1]: *(esp+8)
-#         ...
-    # . prologue
-    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
-    # argv-equal(argv[1], argv[2])
-    # . . push argv[2]
-    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
-    # . . push argv[1]
-    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
-    # . . call
-    e8/call argv-equal/disp32
-    # exit(eax)
-    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           0/r32/eax   .               .                 # copy eax to ebx
-    e8/call  syscall_exit/disp32
-
-# compare two null-terminated ascii strings
-# reason for the name: the only place we should have null-terminated ascii strings is from commandline args
-argv-equal:  # (s1, s2) : null-terminated ascii strings -> eax : boolean
-    # initialize s1 (ecx) and s2 (edx)
-    8b/copy                         1/mod/*+disp8   4/rm32/sib    4/base/esp  4/index/none  .           1/r32/ecx   4/disp8         .                 # copy *(esp+4) to ecx
-    8b/copy                         1/mod/*+disp8   4/rm32/sib    4/base/esp  4/index/none  .           2/r32/edx   8/disp8         .                 # copy *(esp+8) to edx
-$argv-equal:loop:
-    # c1/eax, c2/ebx = *s1, *s2
-    b8/copy-to-eax  0/imm32
-    8a/copy-byte                    0/mod/indirect  1/rm32/ecx    .           .             .           0/r32/AL    .               .                 # copy byte at *ecx to AL
-    bb/copy-to-ebx  0/imm32
-    8a/copy-byte                    0/mod/indirect  2/rm32/edx    .           .             .           3/r32/BL    .               .                 # copy byte at *edx to BL
-    # if (c1 == 0) break
-    3d/compare-eax-and  0/imm32
-    74/jump-if-equal  $argv-equal:break/disp8
-    # if (c1 != c2) return false
-    39/compare                      3/mod/direct    0/rm32/eax    .           .             .           3/r32/ebx   .               .                 # compare eax and ebx
-    75/jump-if-not-equal  $argv-equal:false/disp8
-    # ++s1, ++s2
-    41/increment-ecx
-    42/increment-edx
-    # end while
-    eb/jump  $argv-equal:loop/disp8
-$argv-equal:break:
-    # if (c2 == 0) return true
-    81          7/subop/compare     3/mod/direct    3/rm32/ebx    .           .             .           .           .               0/imm32           # compare ebx
-    75/jump-if-not-equal  $argv-equal:false/disp8
-$argv-equal:success:
-    b8/copy-to-eax  1/imm32
-    c3/return
-    # return false
-$argv-equal:false:
-    b8/copy-to-eax  0/imm32
-    c3/return
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex11 b/examples/ex11
deleted file mode 100755
index 1cb1aa5c..00000000
--- a/examples/ex11
+++ /dev/null
Binary files differdiff --git a/examples/ex11.subx b/examples/ex11.subx
deleted file mode 100644
index b235927d..00000000
--- a/examples/ex11.subx
+++ /dev/null
@@ -1,355 +0,0 @@
-# Null-terminated vs length-prefixed ascii strings.
-#
-# By default we create strings with a 4-byte length prefix rather than a null suffix.
-# However we still need null-prefixed strings when interacting with the Linux
-# kernel in a few places. This layer implements a function for comparing
-# a null-terminated 'kernel string' with a length-prefixed 'SubX string'.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex11.subx -o examples/ex11
-#   $ ./subx run examples/ex11  # runs a series of tests
-#   ......  # all tests pass
-#
-# (We can't yet run the tests when given a "test" commandline argument,
-# because checking for it would require the function being tested! Breakage
-# would cause tests to not run, rather than to fail as we'd like.)
-
-== code
-#   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
-
-Entry:  # run all tests
-    e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
-    # exit(eax)
-    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           0/r32/eax   .               .                 # copy eax to ebx
-    e8/call  syscall_exit/disp32
-
-# 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
-    # pseudocode:
-    #   n = benchmark->length
-    #   s1 = s
-    #   s2 = benchmark->data
-    #   i = 0
-    #   while i < n
-    #     c1 = *s1
-    #     c2 = *s2
-    #     if (c1 == 0) return false
-    #     if (c1 != c2) return false
-    #     ++s1, ++s2, ++i
-    #   return *s1 == 0
-    #
-    # registers:
-    #   i: ecx
-    #   n: edx
-    #   s1: edi
-    #   s2: esi
-    #   c1: eax
-    #   c2: ebx
-    #
-    # . prologue
-    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
-    53/push-ebx
-    56/push-esi
-    57/push-edi
-    # s1/edi = s
-    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           7/r32/edi   8/disp8         .                 # copy *(ebp+8) to edi
-    # n/edx = benchmark->length
-    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           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
-    # s2/esi = benchmark->data
-    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           6/r32/esi   0xc/disp8       .                 # copy *(ebp+12) to esi
-    81          0/subop/add         3/mod/direct    6/rm32/esi    .           .             .           .           .               4/imm32           # add to esi
-    # i/ecx = c1/eax = c2/ebx = 0
-    b9/copy-to-ecx  0/imm32/exit
-    b8/copy-to-eax  0/imm32
-    bb/copy-to-ebx  0/imm32
-$kernel-string-equal?:loop:
-    # if (i >= n) break
-    39/compare                      3/mod/direct    1/rm32/ecx    .           .             .           2/r32/edx   .               .                 # compare ecx with edx
-    7d/jump-if-greater-or-equal  $kernel-string-equal?:break/disp8
-    # c1 = *s1
-    8a/copy-byte                    0/mod/indirect  7/rm32/edi    .           .             .           0/r32/AL    .               .                 # copy byte at *edi to AL
-    # c2 = *s2
-    8a/copy-byte                    0/mod/indirect  6/rm32/esi    .           .             .           3/r32/BL    .               .                 # copy byte at *esi to BL
-    # if (c1 == 0) return false
-    3d/compare-eax-and  0/imm32
-    74/jump-if-equal  $kernel-string-equal?:false/disp8
-    # if (c1 != c2) return false
-    39/compare                      3/mod/direct    0/rm32/eax    .           .             .           3/r32/ebx   .               .                 # compare eax and ebx
-    75/jump-if-not-equal  $kernel-string-equal?:false/disp8
-    # ++i
-    41/increment-ecx
-    # ++s1
-    47/increment-edi
-    # ++s2
-    46/increment-esi
-    eb/jump  $kernel-string-equal?:loop/disp8
-$kernel-string-equal?:break:
-    # return *s1 == 0
-    8a/copy-byte                    0/mod/indirect  7/rm32/edi    .           .             .           0/r32/AL    .               .                 # copy byte at *edi to AL
-    3d/compare-eax-and  0/imm32
-    75/jump-if-not-equal  $kernel-string-equal?:false/disp8
-$kernel-string-equal?:true:
-    b8/copy-to-eax  1/imm32
-    eb/jump  $kernel-string-equal?:end/disp8
-$kernel-string-equal?:false:
-    b8/copy-to-eax  0/imm32
-$kernel-string-equal?:end:
-    # . restore registers
-    5f/pop-to-edi
-    5e/pop-to-esi
-    5b/pop-to-ebx
-    5a/pop-to-edx
-    59/pop-to-ecx
-    # . epilogue
-    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
-    5d/pop-to-ebp
-    c3/return
-
-# - tests
-
-test-compare-null-kernel-string-with-empty-array:
-    # eax = kernel-string-equal?(Null-kernel-string, "")
-    # . . push args
-    68/push  ""/imm32
-    68/push  Null-kernel-string/imm32
-    # . . call
-    e8/call  kernel-string-equal?/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
-    # 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
-    e8/call  check-ints-equal/disp32
-    # . . 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
-    68/push  "Abc"/imm32
-    68/push  Null-kernel-string/imm32
-    # . . call
-    e8/call  kernel-string-equal?/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
-    # 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
-    e8/call  check-ints-equal/disp32
-    # . . 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?(_test-Abc-kernel-string, "Abc")
-    # . . push args
-    68/push  "Abc"/imm32
-    68/push  _test-Abc-kernel-string/imm32
-    # . . call
-    e8/call  kernel-string-equal?/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
-    # 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
-    e8/call  check-ints-equal/disp32
-    # . . 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?(_test-Abc-kernel-string, "Adc")
-    # . . push args
-    68/push  "Adc"/imm32
-    68/push  _test-Abc-kernel-string/imm32
-    # . . call
-    e8/call  kernel-string-equal?/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
-    # 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
-    e8/call  check-ints-equal/disp32
-    # . . 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?(_test-Abc-kernel-string, "")
-    # . . push args
-    68/push  ""/imm32
-    68/push  _test-Abc-kernel-string/imm32
-    # . . call
-    e8/call  kernel-string-equal?/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
-    # 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
-    e8/call  check-ints-equal/disp32
-    # . . 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?(_test-Abc-kernel-string, "Ab")
-    # . . push args
-    68/push  "Ab"/imm32
-    68/push  _test-Abc-kernel-string/imm32
-    # . . call
-    e8/call  kernel-string-equal?/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
-    # check-ints-equal(eax, 0, msg)
-    # . . push args
-    68/push  "F - test-compare-kernel-string-with-shorter-array"/imm32
-    68/push  0/imm32/false
-    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
-    c3/return
-
-test-compare-kernel-string-with-longer-array:
-    # eax = kernel-string-equal?(_test-Abc-kernel-string, "Abcd")
-    # . . push args
-    68/push  "Abcd"/imm32
-    68/push  _test-Abc-kernel-string/imm32
-    # . . call
-    e8/call  kernel-string-equal?/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
-    # check-ints-equal(eax, 0, msg)
-    # . . push args
-    68/push  "F - test-compare-kernel-string-with-longer-array"/imm32
-    68/push  0/imm32/false
-    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
-    c3/return
-
-# - helpers
-
-# print msg to stderr if a != b, otherwise print "."
-check-ints-equal:  # (a : int, b : int, msg : (address array byte)) -> boolean
-    # . prologue
-    55/push-ebp
-    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
-    # . save registers
-    51/push-ecx
-    53/push-ebx
-    # load args into eax, ebx and ecx
-    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           0/r32/eax   8/disp8         .                 # copy *(ebp+8) to eax
-    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           3/r32/ebx   0xc/disp8       .                 # copy *(ebp+12) to ebx
-    # if (eax == b/ebx) print('.') and return
-    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-stderr('.')
-    # . . push args
-    68/push  "."/imm32
-    # . . call
-    e8/call  write-stderr/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . return
-    eb/jump  $check-ints-equal:end/disp8
-    # otherwise print(msg)
-$check-ints-equal:else:
-    # copy msg into ecx
-    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           1/r32/ecx   0x10/disp8       .                # copy *(ebp+16) to ecx
-    # print(ecx)
-    # . . push args
-    51/push-ecx
-    # . . call
-    e8/call  write-stderr/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # print newline
-    # . . push args
-    68/push  Newline/imm32
-    # . . call
-    e8/call  write-stderr/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-$check-ints-equal:end:
-    # . restore registers
-    5b/pop-to-ebx
-    59/pop-to-ecx
-    # end
-    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
-    5d/pop-to-ebp
-    c3/return
-
-write-stderr:  # s : (address array byte) -> <void>
-    # . prologue
-    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
-    # syscall(write, 2/stderr, (data) s+4, (size) *s)
-    # . . fd = 2 (stderr)
-    bb/copy-to-ebx  2/imm32
-    # . . x = s+4
-    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           1/r32/ecx   8/disp8         .                 # copy *(ebp+8) to ecx
-    81          0/subop/add         3/mod/direct    1/rm32/ecx    .           .             .           .           .               4/imm32           # add to ecx
-    # . . size = *s
-    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           2/r32/edx   8/disp8         .                 # copy *(ebp+8) to edx
-    8b/copy                         0/mod/indirect  2/rm32/edx    .           .             .           2/r32/edx   .               .                 # copy *edx to edx
-    # . . syscall
-    e8/call  syscall_write/disp32
-    # . restore registers
-    5b/pop-to-ebx
-    5a/pop-to-edx
-    59/pop-to-ecx
-    58/pop-to-eax
-    # . end
-    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
-    5d/pop-to-ebp
-    c3/return
-
-== data
-
-Newline:
-    # size
-    1/imm32
-    # data
-    0a/newline
-
-# for kernel-string-equal tests
-Null-kernel-string:
-    00/null
-
-_test-Abc-kernel-string:
-    41/A 62/b 63/c 00/null
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex12 b/examples/ex12
deleted file mode 100755
index 80e5deeb..00000000
--- a/examples/ex12
+++ /dev/null
Binary files differdiff --git a/examples/ex12.subx b/examples/ex12.subx
deleted file mode 100644
index 9c67f909..00000000
--- a/examples/ex12.subx
+++ /dev/null
@@ -1,43 +0,0 @@
-# Example showing mmap syscall.
-# Create a new segment using mmap, save the address, write to it.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex12.subx -o examples/ex12
-#   $ ./subx run examples/ex12
-# You shouldn't get a segmentation fault.
-
-== code
-#   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
-
-Entry:
-    # mmap(Mmap-new-segment->len)
-    bb/copy-to-ebx  Mmap-new-segment/imm32
-    e8/call  syscall_mmap/disp32
-
-    # write to *eax to check that we have access to the newly-allocated segment
-    c7          0/subop/copy        0/mod/direct    0/rm32/eax    .           .             .           .           .               0x34/imm32        # copy to *eax
-
-    # exit(eax)
-    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           0/r32/eax   .               .                 # copy eax to ebx
-    e8/call  syscall_exit/disp32
-
-== data
-
-# various constants used here were found in the Linux sources (search for file mman-common.h)
-Mmap-new-segment:  # type mmap_arg_struct
-    # addr
-    0/imm32
-    # len
-    0x100/imm32
-    # protection flags
-    3/imm32  # PROT_READ | PROT_WRITE
-    # sharing flags
-    0x22/imm32  # MAP_PRIVATE | MAP_ANONYMOUS
-    # fd
-    -1/imm32  # since MAP_ANONYMOUS is specified
-    # offset
-    0/imm32  # since MAP_ANONYMOUS is specified
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex2 b/examples/ex2
deleted file mode 100755
index 5e0c1be1..00000000
--- a/examples/ex2
+++ /dev/null
Binary files differdiff --git a/examples/ex2.subx b/examples/ex2.subx
deleted file mode 100644
index 8df4c62c..00000000
--- a/examples/ex2.subx
+++ /dev/null
@@ -1,20 +0,0 @@
-# Add 1 and 1, and return the result in the exit code.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex2.subx -o examples/ex2
-#   $ ./subx run examples/ex2
-# Expected result:
-#   $ echo $?
-#   2
-
-== code
-
-Entry:
-# ebx = 1
-bb/copy-to-ebx  1/imm32
-# increment ebx
-43/increment-ebx
-# exit(ebx)
-e8/call  syscall_exit/disp32
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex3 b/examples/ex3
deleted file mode 100755
index af787c11..00000000
--- a/examples/ex3
+++ /dev/null
Binary files differdiff --git a/examples/ex3.subx b/examples/ex3.subx
deleted file mode 100644
index f6f8c17d..00000000
--- a/examples/ex3.subx
+++ /dev/null
@@ -1,36 +0,0 @@
-# Add the first 10 numbers, and return the result in the exit code.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex3.subx -o examples/ex3
-#   $ ./subx run examples/ex3
-# Expected result:
-#   $ echo $?
-#   55
-
-== code
-#   instruction                     effective address                                                   register    displacement    immediate
-# . op          subop               mod             rm32          base        index         scale       r32
-# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
-
-Entry:
-    # result: ebx = 0
-    bb/copy-to-ebx  0/imm32
-    # counter: ecx = 1
-    b9/copy-to-ecx  1/imm32
-
-$loop:
-    # if (counter > 10) break
-    81          7/subop/compare     3/mod/direct    1/rm32/ecx    .           .             .           .           .               0xa/imm32         # compare ecx
-    7f/jump-if-greater  $exit/disp8
-    # result += counter
-    01/add                          3/mod/direct    3/rm32/ebx    .           .             .           1/r32/ecx   .               .                 # add ecx to ebx
-    # ++counter
-    41/increment-ecx
-    # loop
-    eb/jump  $loop/disp8
-
-$exit:
-    # exit(ebx)
-    e8/call  syscall_exit/disp32
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex4 b/examples/ex4
deleted file mode 100755
index 35ade1ee..00000000
--- a/examples/ex4
+++ /dev/null
Binary files differdiff --git a/examples/ex4.subx b/examples/ex4.subx
deleted file mode 100644
index 78a97433..00000000
--- a/examples/ex4.subx
+++ /dev/null
@@ -1,39 +0,0 @@
-# Read a character from stdin, save it to a global, write it to stdout.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex4.subx -o examples/ex4
-#   $ ./subx run examples/ex4
-
-== data
-
-# the global variable we save to
-X:
-    0/imm32  # space for read() to write to
-
-== code
-
-Entry:
-# read(stdin, X, 1)
-# . fd = 0 (stdin)
-bb/copy-to-ebx  0/imm32
-# . data = X (location to write result to)
-b9/copy-to-ecx  X/imm32
-# . size = 1 character
-ba/copy-to-edx  1/imm32
-# . syscall
-e8/call  syscall_read/disp32
-
-# write(stdout, X, 1)
-# . fd = 1 (stdout)
-bb/copy-to-ebx  1/imm32
-# . initialize X (location to read from)
-b9/copy-to-ecx  X/imm32
-# . size = 1 character
-ba/copy-to-edx  1/imm32
-# . syscall
-e8/call  syscall_write/disp32
-
-# exit(ebx)
-e8/call  syscall_exit/disp32
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex5 b/examples/ex5
deleted file mode 100755
index 805cadc3..00000000
--- a/examples/ex5
+++ /dev/null
Binary files differdiff --git a/examples/ex5.subx b/examples/ex5.subx
deleted file mode 100644
index bacef8d4..00000000
--- a/examples/ex5.subx
+++ /dev/null
@@ -1,41 +0,0 @@
-# Read a character from stdin, save it to a local on the stack, write it to stdout.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex5.subx -o examples/ex5
-#   $ ./subx run examples/ex5
-
-== code
-#   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
-
-Entry:
-
-    # allocate x on the stack
-    81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # subtract from esp
-
-    # read(stdin, x, 1)
-    # . fd = 0 (stdin)
-    bb/copy-to-ebx  0/imm32
-    # . data = x (location to write result to)
-    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    4/base/esp  4/index/none              1/r32/ecx   4/disp8         .                 # copy esp+4 to ecx
-    # . size = 1 character
-    ba/copy-to-edx  1/imm32
-    # . syscall
-    e8/call  syscall_read/disp32
-
-    # syscall(write, stdout, x, 1)
-    # . fd = 1 (stdout)
-    bb/copy-to-ebx  1/imm32
-    # . data = x (location to read from)
-    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    4/base/esp  4/index/none              1/r32/ecx   4/disp8         .                 # copy esp+4 to ecx
-    # . size = 1 character
-    ba/copy-to-edx  1/imm32
-    # . syscall
-    b8/copy-to-eax  4/imm32/write
-    cd/syscall  0x80/imm8
-
-    # exit(ebx)
-    e8/call  syscall_exit/disp32
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex6 b/examples/ex6
deleted file mode 100755
index 06fdfd7b..00000000
--- a/examples/ex6
+++ /dev/null
Binary files differdiff --git a/examples/ex6.subx b/examples/ex6.subx
deleted file mode 100644
index 42612578..00000000
--- a/examples/ex6.subx
+++ /dev/null
@@ -1,35 +0,0 @@
-# Print out a (global variable) string to stdout.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex6.subx -o examples/ex6
-#   $ ./subx run examples/ex6
-#   Hello, world!
-
-== code
-
-# . 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
-
-Entry:
-    # write(stdout, X, Size)
-    # . fd = 1 (stdout)
-    bb/copy-to-ebx  1/imm32
-    # . initialize X (location to write result to)
-    b9/copy-to-ecx  X/imm32
-    # . initialize Size
-    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           2/r32/edx   Size/disp32     .                 # copy *Size to edx
-    # . syscall
-    e8/call  syscall_write/disp32
-
-    # exit(ebx)
-    e8/call  syscall_exit/disp32
-
-== data
-
-Size:  # size of string
-    0x0e/imm32  # 14
-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
diff --git a/examples/ex7 b/examples/ex7
deleted file mode 100755
index 0a535d45..00000000
--- a/examples/ex7
+++ /dev/null
Binary files differdiff --git a/examples/ex7.subx b/examples/ex7.subx
deleted file mode 100644
index 1c551cad..00000000
--- a/examples/ex7.subx
+++ /dev/null
@@ -1,98 +0,0 @@
-# Example showing file syscalls.
-#
-# Create a file, open it for writing, write a character to it, close it, open
-# it for reading, read a character from it, close it, delete it, and return
-# the character read.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex7.subx -o examples/ex7
-#   $ ./subx run examples/ex7
-# Expected result:
-#   $ echo $?
-#   97
-
-== code
-#   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
-
-Entry:
-    # creat(Filename)
-    bb/copy-to-ebx  Filename/imm32
-    b9/copy-to-ecx  0x180/imm32/fixed-perms
-    e8/call  syscall_creat/disp32
-
-    # stream = open(Filename, O_WRONLY, 0)  # we can't use 'fd' because it looks like a hex byte
-    bb/copy-to-ebx  Filename/imm32
-    b9/copy-to-ecx  1/imm32/wronly
-    ba/copy-to-edx  0x180/imm32/fixed-perms
-    e8/call  syscall_open/disp32
-    # save stream
-    bb/copy-to-ebx  Stream/imm32
-    89/copy                         0/mod/indirect  3/rm32/ebx    .           .             .           0/r32/eax   .               .                 # copy eax to *ebx
-
-    # write(Stream, "a", 1)
-    # . load stream
-    bb/copy-to-ebx  Stream/imm32
-    8b/copy                         0/mod/indirect  3/rm32/ebx    .           .             .           3/r32/ebx   .               .                 # copy *ebx to ebx
-    # .
-    b9/copy-to-ecx  A/imm32
-    ba/copy-to-edx  1/imm32/size
-    e8/call  syscall_write/disp32
-
-    # close(Stream)
-    # . load stream
-    bb/copy-to-ebx  Stream/imm32
-    8b/copy                         0/mod/indirect  3/rm32/ebx    .           .             .           3/r32/ebx   .               .                 # copy *ebx to ebx
-    # .
-    e8/call  syscall_close/disp32
-
-    # stream = open(Filename, O_RDONLY, 0)
-    bb/copy-to-ebx  Filename/imm32
-    b9/copy-to-ecx  0/imm32/rdonly
-    ba/copy-to-edx  0x180/imm32/fixed-perms
-    e8/call  syscall_open/disp32
-    # . save Stream
-    bb/copy-to-ebx  Stream/imm32
-    89/copy                         0/mod/indirect  3/rm32/ebx    .           .             .           0/r32/eax   .               .                 # copy eax to *ebx
-
-    # read(Stream, B, 1)
-    # . load stream
-    bb/copy-to-ebx  Stream/imm32
-    8b/copy                         0/mod/indirect  3/rm32/ebx    .           .             .           3/r32/ebx   .               .                 # copy *ebx to ebx
-    # .
-    b9/copy-to-ecx  B/imm32
-    ba/copy-to-edx  1/imm32/size
-    e8/call  syscall_read/disp32
-
-    # close(Stream)
-    # . load stream
-    bb/copy-to-ebx  Stream/imm32
-    8b/copy                         0/mod/indirect  3/rm32/ebx    .           .             .           3/r32/ebx   .               .                 # copy *ebx to ebx
-    #
-    e8/call  syscall_close/disp32
-
-    # unlink(filename)
-    bb/copy-to-ebx  Filename/imm32
-    e8/call  syscall_unlink/disp32
-
-    # exit(b)
-    # . load b
-    bb/copy-to-ebx  B/imm32
-    8b/copy                         0/mod/indirect  3/rm32/ebx    .           .             .           3/r32/ebx   .               .                 # copy *ebx to ebx
-    #
-    e8/call  syscall_exit/disp32
-
-== data
-
-Stream:
-    0/imm32
-A:
-    61/imm32/A
-B:
-    0/imm32
-Filename:
-    2e 66 6f 6f 00 00 00 00
-#   .  f  o  o  null
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex8 b/examples/ex8
deleted file mode 100755
index 78f1773d..00000000
--- a/examples/ex8
+++ /dev/null
Binary files differdiff --git a/examples/ex8.subx b/examples/ex8.subx
deleted file mode 100644
index 0e44a883..00000000
--- a/examples/ex8.subx
+++ /dev/null
@@ -1,60 +0,0 @@
-# Example reading commandline arguments: compute length of first arg.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex8.subx -o examples/ex8
-#   $ ./subx run examples/ex8 abc de fghi
-# Expected result:
-#   $ echo $?
-#   3  # length of 'abc'
-#
-# At the start of a SubX program:
-#   argc: *esp
-#   argv[0]: *(esp+4)
-#   argv[1]: *(esp+8)
-#   ...
-# Locals start from esp-4 downwards.
-
-== code
-#   instruction                     effective address                                                   register    displacement    immediate
-# . op          subop               mod             rm32          base        index         scale       r32
-# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
-
-Entry:
-    # . prologue
-    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
-    # eax = ascii-length(argv[1])
-    # . . push args
-    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
-    # . . call
-    e8/call  ascii-length/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-
-    # exit(eax)
-    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           0/r32/eax   .               .                 # copy eax to ebx
-    e8/call  syscall_exit/disp32
-
-ascii-length:  # s : (address array byte) -> n/eax
-    # edx = s
-    8b/copy                         1/mod/*+disp8   4/rm32/sib    4/base/esp  4/index/none  .           2/r32/edx   4/disp8         .                 # copy *(esp+4) to edx
-    # var result/eax = 0
-    b8/copy-to-eax  0/imm32
-$ascii-length:loop:
-    # var c/ecx = *s
-    8a/copy-byte                    0/mod/*         2/rm32/edx    .           .             .           1/r32/CL    .               .                 # copy byte at *edx to CL
-    # if (c == '\0') break
-    81          7/subop/compare     3/mod/direct    1/rm32/ecx    .           .             .           .           .               0/imm32           # compare ecx
-    74/jump-if-equal  $ascii-length:end/disp8
-    # ++s
-    42/increment-edx
-    # ++result
-    40/increment-eax
-    # loop
-    eb/jump  $ascii-length:loop/disp8
-$ascii-length:end:
-    # return eax
-    c3/return
-
-== data
-
-# . . vim:nowrap:textwidth=0
diff --git a/examples/ex9 b/examples/ex9
deleted file mode 100755
index 5140cf68..00000000
--- a/examples/ex9
+++ /dev/null
Binary files differdiff --git a/examples/ex9.subx b/examples/ex9.subx
deleted file mode 100644
index 443e443e..00000000
--- a/examples/ex9.subx
+++ /dev/null
@@ -1,52 +0,0 @@
-# Example showing arg order on the stack.
-#
-# Show difference between ascii codes of first letter of first arg and first
-# letter of second arg.
-#
-# To run:
-#   $ ./subx translate init.linux examples/ex9.subx -o examples/ex9
-#   $ ./subx run examples/ex9 z x
-# Expected result:
-#   $ echo $?
-#   2
-#
-# At the start of a SubX program:
-#   argc: *esp
-#   argv[0]: *(esp+4)
-#   argv[1]: *(esp+8)
-#   ...
-# Locals start from esp-4 downwards.
-
-== code
-#   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
-
-Entry:
-    # . prologue
-    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
-    # ascii-difference(argv[1], argv[2])
-    # . . push argv[2]
-    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
-    # . . push argv[1]
-    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
-    # . . call
-    e8/call  ascii-difference/disp32
-    # . . 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
-    e8/call  syscall_exit/disp32
-
-ascii-difference:  # (s1, s2) : null-terminated ascii strings
-    # a = first letter of s1 (ecx)
-    8b/copy                         1/mod/*+disp8   4/rm32/sib    4/base/esp  4/index/none              0/r32/eax   4/disp8         .                 # copy *(esp+4) to eax
-    8b/copy                         0/mod/indirect  0/rm32/eax    .           .             .           0/r32/eax   .               .                 # copy *eax to eax
-    # b = first letter of s2 (edx)
-    8b/copy                         1/mod/*+disp8   4/rm32/sib    4/base/esp  4/index/none              1/r32/ecx   8/disp8                           # copy *(esp+8) to ecx
-    8b/copy                         0/mod/indirect  1/rm32/ecx    .           .             .           1/r32/ecx   .               .                 # copy *ecx to ecx
-    # a-b
-    29/subtract                     3/mod/direct    0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # subtract ecx from eax
-    c3/return
-
-# . . vim:nowrap:textwidth=0