diff options
Diffstat (limited to 'subx/examples/ex8.subx')
| -rw-r--r-- | subx/examples/ex8.subx | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/subx/examples/ex8.subx b/subx/examples/ex8.subx index 410dfe08..6ec9eb3c 100644 --- a/subx/examples/ex8.subx +++ b/subx/examples/ex8.subx @@ -1,4 +1,4 @@ -## Example reading commandline arguments: compute length of first arg. +# Example reading commandline arguments: compute length of first arg. # # To run (from the subx directory): # $ subx translate examples/ex8.subx -o examples/ex8 @@ -21,7 +21,7 @@ # . prolog 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP - # . . call ascii-length(argv[1]) + # EAX = ascii-length(argv[1]) # . . push args ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 0x8/disp8 . # push *(EBP+8) # . . call @@ -34,13 +34,13 @@ b8/copy-to-EAX 1/imm32/exit cd/syscall 0x80/imm8 -ascii-length: # (s) - # initialize s (EDX) +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 = 0 (EAX) + # var result/EAX = 0 b8/copy-to-EAX 0/imm32 $ascii-length-loop: - # var c = *s (ECX) + # var c/ECX = *s 8a/copy 0/mod/* 2/rm32/EDX . . . 1/r32/ECX . . # copy byte at *EDX to lower byte of ECX # if c == '\0' break 81 7/subop/compare 3/mod/direct 1/rm32/ECX . . . . . 0/imm32 # compare ECX @@ -52,7 +52,7 @@ $ascii-length-loop: # loop eb/jump $ascii-length-loop/disp8 $ascii-length-ret: - # return (result in EAX) + # return EAX c3/return # . . vim:nowrap:textwidth=0 |