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page ,132 title stricmp;***;stricmp.asm - contains ASCII only, case-insensitive, string comparision routine; __ascii_stricmp;; Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.;;Purpose:; contains __ascii_stricmp();;Revision History:; 05-18-88 SJM Add model-independent (large model) ifdef; 08-04-88 SJM convert to cruntime/ add 32-bit support; 08-23-88 JCR Minor 386 cleanup; 10-10-88 JCR Added strcmpi() entry for compatiblity with early revs; 10-25-88 JCR General cleanup for 386-only code; 10-27-88 JCR Shuffled regs so no need to save/restore ebx; 03-23-90 GJF Changed to _stdcall. Also, fixed the copyright.; 01-18-91 GJF ANSI naming.; 05-10-91 GJF Back to _cdecl, sigh...; 10-20-94 GJF Made locale sensitive (i.e., now works for all; single-byte character locales). Made multi-thread; safe. Also, deleted obsolete _STDCALL_ code.; 10-27-94 GJF Adapted above change for Win32S.; 11-12-94 GJF Must avoid volatile regs or save them across function; calls. Also, fixed bug in reg operand size.; 07-03-95 CFW Changed offset of _lc_handle[LC_CTYPE], added sanity check ; to crtlib.c to catch changes to win32s.h that modify offset.; 10-03-95 GJF New locale locking scheme.; 11-13-95 GJF Made _strcmpi a proc instead of a label.; 07-17-96 GJF Added lock prefix to increment and decrement of ; __unguarded_readlc_active; 07-18-96 GJF Fixed race condition.; 08-26-98 GJF All locale and multithread support moved up to; stricmp.c. Renamed this file to _stricmp.asm.; 06-12-01 PML inc->add 1, dec->sub 1 for Pentium 4 perf (vs7#267015);;*******************************************************************************
.xlist include cruntime.inc .list
page;***;int __ascii_stricmp(dst, src) - compare strings, ignore case;;Purpose:; _stricmp/_strcmpi perform a case-insensitive string comparision.; For differences, upper case letters are mapped to lower case.; Thus, "abc_" < "ABCD" since "_" < "d".;; Algorithm:;; int _strcmpi (char * dst, char * src); {; int f,l;;; do {; f = tolower(*dst);; l = tolower(*src);; dst++;; src++;; } while (f && f == l);;; return(f - l);; };;Entry:; char *dst, *src - strings to compare;;Exit:; AX = -1 if dst < src; AX = 0 if dst = src; AX = +1 if dst > src;;Uses:; CX, DX;;Exceptions:;;*******************************************************************************
CODESEG
public __ascii_stricmp__ascii_stricmp proc \ uses edi esi ebx, \ dst:ptr, \ src:ptr
; load up args
mov esi,[src] ; esi = src mov edi,[dst] ; edi = dst
mov al,-1 ; fall into loop
align 4
chk_null: or al,al jz short done
mov al,[esi] ; al = next source byte add esi,1 mov ah,[edi] ; ah = next dest byte add edi,1
cmp ah,al ; first try case-sensitive comparision je short chk_null ; match
sub al,'A' cmp al,'Z'-'A'+1 sbb cl,cl and cl,'a'-'A' add al,cl add al,'A' ; tolower(*dst)
xchg ah,al ; operations on AL are shorter than AH
sub al,'A' cmp al,'Z'-'A'+1 sbb cl,cl and cl,'a'-'A' add al,cl add al,'A' ; tolower(*src)
cmp al,ah ; inverse of above comparison -- AL & AH are swapped je short chk_null
; dst < src dst > src sbb al,al ; AL=-1, CY=1 AL=0, CY=0 sbb al,-1 ; AL=-1 AL=1done: movsx eax,al ; extend al to eax
ret
__ascii_stricmp endp end
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