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-rw-r--r--067parse-hex.subx4
-rwxr-xr-xapps/desugarbin44534 -> 45981 bytes
-rw-r--r--apps/desugar.subx457
3 files changed, 422 insertions, 39 deletions
diff --git a/067parse-hex.subx b/067parse-hex.subx
index 45d168d9..185e471f 100644
--- a/067parse-hex.subx
+++ b/067parse-hex.subx
@@ -621,10 +621,10 @@ test-parse-hex-int-negative:
     e8/call  parse-hex-int/disp32
     # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
-    # check-ints-equal(EAX, 0xfffffffd, msg)
+    # check-ints-equal(EAX, -3, msg)
     # . . push args
     68/push  "F - test-parse-hex-int-negative"/imm32
-    68/push  0xfffffffd/imm32
+    68/push  -3/imm32
     50/push-EAX
     # . . call
     e8/call  check-ints-equal/disp32
diff --git a/apps/desugar b/apps/desugar
index bfdec579..e8084ddf 100755
--- a/apps/desugar
+++ b/apps/desugar
Binary files differdiff --git a/apps/desugar.subx b/apps/desugar.subx
index cbd8a408..4f2db492 100644
--- a/apps/desugar.subx
+++ b/apps/desugar.subx
@@ -1507,7 +1507,7 @@ parse-effective-address:  # word : (address slice) -> base/EAX, index/ECX, scale
     #     if (*word->start != '<') goto error3
     #     ++word->start to skip '<'
     #     skip whitespace
-    #     read register into scale
+    #     read integer into scale
     #     skip whitespace
     #     if (*word->start == ')') goto end
     #   }
@@ -1671,15 +1671,52 @@ $parse-effective-address:index:
     3d/compare-EAX-and  0x29/imm32/close-paren
     74/jump-if-equal  $parse-effective-address:end/disp8
 $parse-effective-address:check-for-scale:
-    # if (*word->start != '<') goto displacement
+    # if (*word->start != '<') goto next check
+    3d/compare-EAX-and  0x3c/imm32/less-than
+    75/jump-if-not-equal  $parse-effective-address:check-for-displacement/disp8
     # ++word->start to skip '<'
+    ff          0/subop/increment   0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # increment *ESI
     # if (*word->start != '<') goto error3
     # ++word->start to skip '<'
+    ff          0/subop/increment   0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # increment *ESI
     # skip whitespace
+    # . EAX = skip-chars-matching-whitespace-in-slice(word->start, word->end)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   6/rm32/ESI    .           .             .           .           4/disp8         .                 # push *(ESI+4)
+    ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
+    # . . call
+    e8/call  skip-chars-matching-whitespace-in-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . word->start = EAX
+    89/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy EAX to *ESI
 $parse-effective-address:scale:
-    # read register into scale
+    # read positive integer into scale
+    # . EAX = next-positive-hex-int(word)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-positive-hex-int/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . EDX = EAX
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EDX
     # skip whitespace
+    # . EAX = skip-chars-matching-whitespace-in-slice(word->start, word->end)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   6/rm32/ESI    .           .             .           .           4/disp8         .                 # push *(ESI+4)
+    ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
+    # . . call
+    e8/call  skip-chars-matching-whitespace-in-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . word->start = EAX
+    89/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy EAX to *ESI
     # if (*word->start == ')') goto end
+    8a/copy-byte                    0/mod/indirect  0/rm32/EAX    .           .             .           0/r32/AL    .               .                 # copy byte at *EAX to AL
+    81          4/subop/and         3/mod/direct    0/rm32/EAX    .           .             .           .           .               0xff/imm32        # bitwise and of EAX
+    3d/compare-EAX-and  0x29/imm32/close-paren
+    74/jump-if-equal  $parse-effective-address:end/disp8
 $parse-effective-address:check-for-displacement:
     # if (*word->start not in '+' '-') goto error4
 $parse-effective-address:displacement:
@@ -1692,7 +1729,7 @@ $parse-effective-address:displacement:
     # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
     # . EBX = EAX
-    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EBX to EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EBX
     # skip whitespace
     # . EAX = skip-chars-matching-whitespace-in-slice(word->start, word->end)
     # . . push args
@@ -2066,9 +2103,129 @@ test-parse-effective-address-base-index:
     5d/pop-to-EBP
     c3/return
 
-#? test-parse-effective-address-base-index-scale:
-#? 
-#? test-parse-effective-address-base-index-scale-displacement:
+test-parse-effective-address-base-index-scale:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # var slice/ECX = "*(esi+ecx<<2)"
+    b8/copy-to-EAX  "*(esi+ecx<<2)"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # . ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX, ECX, EDX, EBX = parse-effective-address(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-effective-address/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # slice clobbered beyond this point
+    # check-ints-equal(EAX, 6, msg)
+    # . . push args
+    68/push  "F - test-parse-effective-address-base-index-scale/base"/imm32
+    68/push  6/imm32/ESI
+    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(ECX, 1, msg)
+    # . . push args
+    68/push  "F - test-parse-effective-address-base-index-scale/index"/imm32
+    68/push  1/imm32/none
+    51/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-ints-equal(EDX, 2, msg)
+    # . . push args
+    68/push  "F - test-parse-effective-address-base-index-scale/scale"/imm32
+    68/push  2/imm32
+    52/push-EDX
+    # . . 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(EBX, 0, msg)
+    # . . push args
+    68/push  "F - test-parse-effective-address-base-index-scale/displacement"/imm32
+    68/push  0/imm32
+    53/push-EBX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-parse-effective-address-base-index-scale-displacement:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # var slice/ECX = "*(esi + ecx<<2 - 0x34)"
+    b8/copy-to-EAX  "*(esi + ecx<<2 - 0x34)"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # . ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX, ECX, EDX, EBX = parse-effective-address(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-effective-address/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # slice clobbered beyond this point
+    # check-ints-equal(EAX, 6, msg)
+    # . . push args
+    68/push  "F - test-parse-effective-address-base-index-scale/base"/imm32
+    68/push  6/imm32/ESI
+    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(ECX, 1, msg)
+    # . . push args
+    68/push  "F - test-parse-effective-address-base-index-scale/index"/imm32
+    68/push  1/imm32/none
+    51/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-ints-equal(EDX, 2, msg)
+    # . . push args
+    68/push  "F - test-parse-effective-address-base-index-scale/scale"/imm32
+    68/push  2/imm32
+    52/push-EDX
+    # . . 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(EBX, -0x34, msg)
+    # . . push args
+    68/push  "F - test-parse-effective-address-base-index-scale/displacement"/imm32
+    68/push  -0x34/imm32
+    53/push-EBX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
 
 # Code generation:
 #   if index is none and disp is 0, then mod = 0 and rm32 = base
@@ -2774,8 +2931,8 @@ test-next-hex-int-single-digit:
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # (EAX..ECX) = "+a"
-    b8/copy-to-EAX  "+a"/imm32
+    # (EAX..ECX) = "+a)"
+    b8/copy-to-EAX  "+a)"/imm32
     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
     05/add-to-EAX  4/imm32
@@ -2808,8 +2965,8 @@ test-next-hex-int-multi-digit:
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # (EAX..ECX) = "+ 34a"
-    b8/copy-to-EAX  "+ 34a"/imm32
+    # (EAX..ECX) = "+ 34a)"
+    b8/copy-to-EAX  "+ 34a)"/imm32
     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
     05/add-to-EAX  4/imm32
@@ -2842,8 +2999,8 @@ test-next-hex-int-0x-prefix:
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # (EAX..ECX) = "0x34"
-    b8/copy-to-EAX  "+0x34"/imm32
+    # (EAX..ECX) = "+0x34)"
+    b8/copy-to-EAX  "+0x34)"/imm32
     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
     05/add-to-EAX  4/imm32
@@ -2858,7 +3015,7 @@ test-next-hex-int-0x-prefix:
     e8/call  next-hex-int/disp32
     # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
-    # check-ints-equal(EAX, 0x34a, msg)
+    # check-ints-equal(EAX, 0x34, msg)
     # . . push args
     68/push  "F - test-next-hex-int-0x-prefix"/imm32
     68/push  0x34/imm32
@@ -2876,8 +3033,8 @@ test-next-hex-int-zero:
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # (EAX..ECX) = "+0"
-    b8/copy-to-EAX  "+0"/imm32
+    # (EAX..ECX) = "+0)"
+    b8/copy-to-EAX  "+0)"/imm32
     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
     05/add-to-EAX  4/imm32
@@ -2892,7 +3049,7 @@ test-next-hex-int-zero:
     e8/call  next-hex-int/disp32
     # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
-    # check-ints-equal(EAX, 0x34a, msg)
+    # check-ints-equal(EAX, 0, msg)
     # . . push args
     68/push  "F - test-next-hex-int-zero"/imm32
     68/push  0/imm32
@@ -2910,8 +3067,8 @@ test-next-hex-int-0-prefix:
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # (EAX..ECX) = "+ 03"
-    b8/copy-to-EAX  "+ 03"/imm32
+    # (EAX..ECX) = "+ 03)"
+    b8/copy-to-EAX  "+ 03)"/imm32
     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
     05/add-to-EAX  4/imm32
@@ -2926,10 +3083,10 @@ test-next-hex-int-0-prefix:
     e8/call  next-hex-int/disp32
     # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
-    # check-ints-equal(EAX, 0x3, msg)
+    # check-ints-equal(EAX, 3, msg)
     # . . push args
     68/push  "F - test-next-hex-int-0-prefix"/imm32
-    68/push  0x3/imm32
+    68/push  3/imm32
     50/push-EAX
     # . . call
     e8/call  check-ints-equal/disp32
@@ -2944,8 +3101,8 @@ test-next-hex-int-negative:
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # (EAX..ECX) = "-03"
-    b8/copy-to-EAX  "-03"/imm32
+    # (EAX..ECX) = "-03)"
+    b8/copy-to-EAX  "-03)"/imm32
     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
     05/add-to-EAX  4/imm32
@@ -2960,10 +3117,10 @@ test-next-hex-int-negative:
     e8/call  next-hex-int/disp32
     # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
-    # check-ints-equal(EAX, 0xfffffffd, msg)
+    # check-ints-equal(EAX, -3, msg)
     # . . push args
     68/push  "F - test-next-hex-int-negative"/imm32
-    68/push  0xfffffffd/imm32
+    68/push  -3/imm32
     50/push-EAX
     # . . call
     e8/call  check-ints-equal/disp32
@@ -2978,8 +3135,8 @@ test-next-hex-int-negative-with-space:
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # (EAX..ECX) = "- 03"
-    b8/copy-to-EAX  "- 03"/imm32
+    # (EAX..ECX) = "- 03)"
+    b8/copy-to-EAX  "- 03)"/imm32
     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
     05/add-to-EAX  4/imm32
@@ -2994,10 +3151,10 @@ test-next-hex-int-negative-with-space:
     e8/call  next-hex-int/disp32
     # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
-    # check-ints-equal(EAX, 0xfffffffd, msg)
+    # check-ints-equal(EAX, -3, msg)
     # . . push args
     68/push  "F - test-next-hex-int-negative-with-space"/imm32
-    68/push  0xfffffffd/imm32
+    68/push  -3/imm32
     50/push-EAX
     # . . call
     e8/call  check-ints-equal/disp32
@@ -3008,12 +3165,102 @@ test-next-hex-int-negative-with-space:
     5d/pop-to-EBP
     c3/return
 
-test-next-hex-int-stop-at-non-hex:
+# assumes 'in' starts a positive unsigned integer
+# returns the value of the integer
+# side-effect: modifies 'in' to skip past the integer
+next-positive-hex-int:  # in : (address slice) -> result/EAX
     # . prolog
     55/push-EBP
     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # (EAX..ECX) = "- 03)"
-    b8/copy-to-EAX  "- 03)"/imm32
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # result/EDI = 0
+    31/xor                          3/mod/direct    7/rm32/EDI    .           .             .           7/r32/EDI   .               .                 # clear EDI
+    # ESI = in
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # EDX = in->end
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(ESI+4) to EDX
+    # curr/ECX = in->start
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    # negate?/EBX = false
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+    # EAX = *curr
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+$next-positive-hex-int:initial-0:
+    # skip past leading '0x'
+    # . if (*curr != '0') jump to loop
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+    3d/compare-EAX-and  0x30/imm32/0
+    75/jump-if-not-equal  $next-positive-hex-int:loop/disp8
+    # . ++curr
+    41/increment-ECX
+$next-positive-hex-int:initial-0x:
+    # . if (curr >= in->end) return result
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-or-equal-unsigned  $next-positive-hex-int:end/disp8
+    # . if (*curr != 'x') jump to loop  # the previous '0' is still valid so doesn't need to be checked again
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+    3d/compare-EAX-and  0x78/imm32/x
+    75/jump-if-not-equal  $next-positive-hex-int:loop/disp8
+    # . ++curr
+    41/increment-ECX
+$next-positive-hex-int:loop:
+    # if (curr >= in->end) break
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-or-equal-unsigned  $next-positive-hex-int:end/disp8
+    # if (!is-hex-digit?(*curr)) break
+    # . EAX = *curr
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+    # . EAX = is-hex-digit?(*curr)
+    # . . push args
+    50/push-EAX
+    # . . call
+    e8/call  is-hex-digit?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX == 0) break
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $next-positive-hex-int:end/disp8
+    # EAX = from-hex-char(*curr)
+    # . . copy arg to EAX
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+    # . . call
+    e8/call  from-hex-char/disp32
+    # result = result * 16 + EAX
+    c1/shift    4/subop/left        3/mod/direct    7/rm32/EDI    .           .             .           .           .               4/imm8            # shift EDI left by 4 bits
+    01/add                          3/mod/direct    7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # add EAX to EDI
+    # ++curr
+    41/increment-ECX
+    # loop
+    eb/jump  $next-positive-hex-int:loop/disp8
+$next-positive-hex-int:end:
+    # word->start = curr
+    89/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy ECX to *ESI
+    # return EDI
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           7/r32/EDI   .               .                 # copy EDI to EAX
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    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
+
+test-next-positive-hex-int-single-digit:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "a)"
+    b8/copy-to-EAX  "a)"/imm32
     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
     05/add-to-EAX  4/imm32
@@ -3021,17 +3268,153 @@ test-next-hex-int-stop-at-non-hex:
     51/push-ECX
     50/push-EAX
     89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
-    # EAX = next-hex-int(slice)
+    # EAX = next-positive-hex-int(slice)
     # . . push args
     51/push-ECX
     # . . call
-    e8/call  next-hex-int/disp32
+    e8/call  next-positive-hex-int/disp32
     # . . discard args
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
-    # check-ints-equal(EAX, 0xfffffffd, msg)
+    # check-ints-equal(EAX, 0xa, msg)
+    # . . push args
+    68/push  "F - test-next-positive-hex-int-single-digit"/imm32
+    68/push  0xa/imm32
+    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
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-positive-hex-int-multi-digit:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "34a)"
+    b8/copy-to-EAX  "34a)"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = next-positive-hex-int(slice)
     # . . push args
-    68/push  "F - test-next-hex-int-stop-at-non-hex"/imm32
-    68/push  0xfffffffd/imm32
+    51/push-ECX
+    # . . call
+    e8/call  next-positive-hex-int/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0x34a, msg)
+    # . . push args
+    68/push  "F - test-next-positive-hex-int-multi-digit"/imm32
+    68/push  0x34a/imm32
+    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
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-positive-hex-int-0x-prefix:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "0x34)"
+    b8/copy-to-EAX  "0x34)"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = next-positive-hex-int(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  next-positive-hex-int/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0x34, msg)
+    # . . push args
+    68/push  "F - test-next-positive-hex-int-0x-prefix"/imm32
+    68/push  0x34/imm32
+    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
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-positive-hex-int-zero:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "0"
+    b8/copy-to-EAX  "0"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = next-positive-hex-int(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  next-positive-hex-int/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-next-positive-hex-int-zero"/imm32
+    68/push  0/imm32
+    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
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-positive-hex-int-0-prefix:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "03)"
+    b8/copy-to-EAX  "03)"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = next-positive-hex-int(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  next-positive-hex-int/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 3, msg)
+    # . . push args
+    68/push  "F - test-next-positive-hex-int-0-prefix"/imm32
+    68/push  3/imm32
     50/push-EAX
     # . . call
     e8/call  check-ints-equal/disp32