4929

Clean up primitives for converting from/to hex chars.

15 files changed, 28 insertions, 57 deletions

diff --git a/subx/071hex.subx b/subx/063hex.subx
index 754e674e..6c36c74b 100644
--- a/subx/071hex.subx
+++ b/subx/063hex.subx
@@ -309,14 +309,11 @@ $parse-hex-int:loop:
     # if (curr >= in->end) break
     39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
     7d/jump-if-greater-or-equal  $parse-hex-int:negate/disp8
-    # EAX = parse-hex-digit(*curr)
-    # . . push args
+    # 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
-    50/push-EAX
     # . . call
-    e8/call  parse-hex-digit/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    e8/call  from-hex-char/disp32
     # result = result * 16 + EAX
     c1/shift    4/subop/left        3/mod/direct    3/rm32/EBX    .           .             .           .           .               4/imm8            # shift EBX left by 4 bits
     01/add                          3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # add EAX to EBX
@@ -673,18 +670,30 @@ test-hex-above-f:
     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
     c3/return
 
-parse-hex-digit:  # in/EAX : byte -> out/EAX : num
+from-hex-char:  # in/EAX : byte -> out/EAX : num
     # no error checking; accepts argument in EAX
     # if EAX <= '9' return EAX - '0'
     3d/compare-EAX  0x39/imm32/9
-    7f/jump-if-greater  $parse-hex-digit:else/disp8
+    7f/jump-if-greater  $from-hex-char:else/disp8
     2d/subtract-from-EAX  0x30/imm32/0
     c3/return
-$parse-hex-digit:else:
+$from-hex-char:else:
     # otherwise return EAX - 'a' + 10
     2d/subtract-from-EAX  0x57/imm32/a-10
     c3/return
 
+to-hex-char:  # in/EAX : nibble -> out/EAX : byte
+    # no error checking; accepts argument in EAX
+    # if EAX <= 9 return EAX + '0'
+    3d/compare-EAX  0x9/imm32/9
+    7f/jump-if-greater  $to-hex-char:else/disp8
+    05/add-to-EAX  0x30/imm32/0
+    c3/return
+$to-hex-char:else:
+    # otherwise return EAX + 'a' - 10
+    05/add-to-EAX  0x57/imm32/a-10
+    c3/return
+
 == data
 
 _test-slice-empty:
diff --git a/subx/063print-byte.subx b/subx/064print-byte.subx
index 8bd9fbfc..dacc78d9 100644
--- a/subx/063print-byte.subx
+++ b/subx/064print-byte.subx
@@ -21,13 +21,8 @@ print-byte:  # f : (address buffered-file), n : int -> <void>
     # AL = convert upper nibble to hex
     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy *(EBP+12) to EAX
     c1/shift    5/subop/logic-right 3/mod/direct    0/rm32/EAX    .           .             .           .           .               4/imm8            # shift EAX right by 4 bits, while padding zeroes
-    # . hex-char(AL)
-    # . . push args
-    50/push-EAX
-    # . . call
-    e8/call  hex-char/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . AL = to-hex-char(AL)
+    e8/call  to-hex-char/disp32
     # write-byte(f, AL)
     # . . push args
     50/push-EAX
@@ -39,13 +34,8 @@ print-byte:  # f : (address buffered-file), n : int -> <void>
     # AL = convert lower nibble to hex
     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy *(EBP+12) to EAX
     25/and-EAX  0xf/imm32
-    # . hex-char(AL)
-    # . . push args
-    50/push-EAX
-    # . . call
-    e8/call  hex-char/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . AL = to-hex-char(AL)
+    e8/call  to-hex-char/disp32
     # write-byte(f, AL)
     # . . push args
     50/push-EAX
@@ -63,34 +53,6 @@ $print-byte:end:
     5d/pop-to-EBP
     c3/return
 
-# extract lowest 4 bits and convert to 8-byte ascii
-# return 0xffffffff if more than 4 bits are set
-hex-char:  # n : int -> char_or_error/EAX
-    # . prolog
-    55/push-EBP
-    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
-    # EAX = n
-    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   8/disp8         .                 # copy *(EBP+8) to EAX
-    # if it's <= 9 add '0' to it
-    81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0x9/imm32         # compare EAX
-    7f/jump-if-greater  $hex-char:check2/disp8
-    05/add-to-EAX  0x30/imm32/'0'
-    eb/jump  $hex-char:end/disp8
-$hex-char:check2:
-    # else if it's <= 15 add ('a' - 10) to it
-    81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0xf/imm32         # compare EAX
-    7f/jump-if-greater  $hex-char:error/disp8
-    05/add-to-EAX  0x57/imm32  # 'a' - 10
-    eb/jump  $hex-char:end/disp8
-$hex-char:error:
-    # otherwise return 0xffffffff
-    b8/copy-to-EAX  0xffffffff/imm32
-$hex-char:end:
-    # . epilog
-    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
-    5d/pop-to-EBP
-    c3/return
-
 test-print-byte:
     # - check that print-byte prints the hex textual representation
     # setup
diff --git a/subx/064write-buffered.subx b/subx/065write-buffered.subx
index 9ae08b21..9ae08b21 100644
--- a/subx/064write-buffered.subx
+++ b/subx/065write-buffered.subx
diff --git a/subx/065error-byte.subx b/subx/066error-byte.subx
index 5f9a4ada..5f9a4ada 100644
--- a/subx/065error-byte.subx
+++ b/subx/066error-byte.subx
diff --git a/subx/066allocate.subx b/subx/067allocate.subx
index 37b01d21..37b01d21 100644
--- a/subx/066allocate.subx
+++ b/subx/067allocate.subx
diff --git a/subx/067new-stream.subx b/subx/068new-stream.subx
index 2020229d..2020229d 100644
--- a/subx/067new-stream.subx
+++ b/subx/068new-stream.subx
diff --git a/subx/068read-line.subx b/subx/069read-line.subx
index 961fc521..961fc521 100644
--- a/subx/068read-line.subx
+++ b/subx/069read-line.subx
diff --git a/subx/069slice.subx b/subx/070slice.subx
index 7be920ec..7be920ec 100644
--- a/subx/069slice.subx
+++ b/subx/070slice.subx
diff --git a/subx/070next-token.subx b/subx/071next-token.subx
index 539caf95..539caf95 100644
--- a/subx/070next-token.subx
+++ b/subx/071next-token.subx
diff --git a/subx/apps/crenshaw2-1 b/subx/apps/crenshaw2-1
index 1d314e4e..8010cdac 100755
--- a/subx/apps/crenshaw2-1
+++ b/subx/apps/crenshaw2-1
Binary files differdiff --git a/subx/apps/crenshaw2-1b b/subx/apps/crenshaw2-1b
index b18e13a1..3cdb555e 100755
--- a/subx/apps/crenshaw2-1b
+++ b/subx/apps/crenshaw2-1b
Binary files differdiff --git a/subx/apps/factorial b/subx/apps/factorial
index dc2b81ad..4489b6ad 100755
--- a/subx/apps/factorial
+++ b/subx/apps/factorial
Binary files differdiff --git a/subx/apps/handle b/subx/apps/handle
index 6a6d12f9..65b94caa 100755
--- a/subx/apps/handle
+++ b/subx/apps/handle
Binary files differdiff --git a/subx/apps/hex b/subx/apps/hex
index 95f1956c..66aa0dce 100755
--- a/subx/apps/hex
+++ b/subx/apps/hex
Binary files differdiff --git a/subx/apps/hex.subx b/subx/apps/hex.subx
index 0d2caefe..52e910f8 100644
--- a/subx/apps/hex.subx
+++ b/subx/apps/hex.subx
@@ -131,10 +131,10 @@ convert-next-octet:  # in : (address buffered-file), err : (address buffered-fil
     # pseudocode:
     #   EAX = scan-next-byte(in, err, ed)
     #   if (EAX == 0xffffffff) return
-    #   ECX = parse-hex-digit(EAX)
+    #   ECX = from-hex-char(EAX)
     #   EAX = scan-next-byte(in, err, ed)
     #   if (EAX == 0xffffffff) error("partial byte found.")
-    #   EAX = parse-hex-digit(EAX)
+    #   EAX = from-hex-char(EAX)
     #   EAX = (ECX << 4) | EAX
     #   return
     #
@@ -155,8 +155,8 @@ convert-next-octet:  # in : (address buffered-file), err : (address buffered-fil
     # if (EAX == 0xffffffff) return
     81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0xffffffff/imm32  # compare EAX
     74/jump-if-equal  $convert-next-octet:end/disp8
-    # EAX = parse-hex-digit(EAX)
-    e8/call parse-hex-digit/disp32
+    # EAX = from-hex-char(EAX)
+    e8/call from-hex-char/disp32
     # ECX = EAX
     89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy EAX to ECX
     # EAX = scan-next-byte(in, err, ed)
@@ -180,8 +180,8 @@ convert-next-octet:  # in : (address buffered-file), err : (address buffered-fil
     # . . call
     e8/call  error-byte/disp32  # never returns
 $convert-next-octet:convert:
-    # EAX = parse-hex-digit(EAX)
-    e8/call parse-hex-digit/disp32
+    # EAX = from-hex-char(EAX)
+    e8/call from-hex-char/disp32
     # EAX = (ECX << 4) | EAX
     # . ECX <<= 4
     c1/shift    4/subop/left        3/mod/direct    1/rm32/ECX    .           .             .           .           .               4/imm8            # shift ECX left by 4 bits