[retroforth] Speed up of 'find' word
- From: "Ron Aaron" <ron@xxxxxxxxxxx>
- To: retroforth@xxxxxxxxxxxxx
- Date: Tue, 25 Jan 2005 09:03:20 -0800 (PST)
'find' currently only does a full check of the word if it's the same length as
the word sought. This is good; but it can be further sped up by only doing
the rep cmpsb if the first char is the same. This prevents a lot of push/pop
and the cmpsb:
; trashes EDX
code 'find', find ;
push ebx ;
mov ebx, flast ;
.o: push ecx ;
upop ecx ;
; get first char to do quick compare:
mov dl, byte [eax]
.a: mov ebx,[ebx] ;
or ebx,ebx ;
jz .end ;
cmp cl,[ebx+8] ;
jne .a ;
; same length; compare first char
cmp dl, [ebx+9]
jne .a
.len: push esi ; same length
push edi ;
push ecx ;
mov esi,eax ;
lea edi,[ebx+9] ;
rep cmpsb ;
pop ecx ;
pop edi ;
pop esi ;
jne .a ;
mov eax,[ebx+4] ; exact match
clc ;
jmp .ret ;
.end: upsh ecx ; no matches
stc ;
.ret: pop ecx ;
pop ebx ;
next
--
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fingerprint: 8130 734C 69A3 6542 0853 CB42 3ECF 9259 AD29 415D
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