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* much faster strcopy and strscan procedures

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This commit is contained in:
Jonas Maebe 2000-06-11 14:25:23 +00:00
parent f0f4a1d74e
commit 9cf6b9f89d
1 changed files with 114 additions and 34 deletions
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148
rtl/i386/strings.inc
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@ -19,26 +19,50 @@
function strcopy(dest,source : pchar) : pchar;assembler;
asm
cld
movl source,%edi
orl %edi,%edi
jz .LStrCopyNil
movl $0xffffffff,%ecx
xorb %al,%al
repne
scasb
not %ecx
movl dest,%edi
testl %edi,%edi
jz .LStrCopyDone
movl %edi,%ecx
andl $0x0fffffff8,%edi
movl source,%esi
movl %ecx,%eax
shrl $2,%ecx
rep
movsl
movl %eax,%ecx
andl $3,%ecx
rep
movsb
.LStrCopyNil:
subl %edi,%ecx
movl dest,%edi
jz .LStrCopyAligned
.LStrCopyAlignLoop:
movb (%esi),%al
incl %edi
incl %esi
testb %al,%al
movb %al,-1(%edi)
jz .LStrCopyDone
decl %ecx
jnz .LStrCopyAlignLoop
.align 16
.LStrCopyAligned:
movl (%esi),%eax
addl $4,%esi
testl $0x0ff,%eax
jz .LStrCopyByte
testl $0x0ff00,%eax
jz .LStrCopyWord
testl $0x0ff0000,%eax
jz .LStrCopy3Bytes
movl %eax,(%edi)
testl $0x0ff000000,%eax
jz .LStrCopyDone
addl $4,%edi
jmp .LStrCopyAligned
.LStrCopy3Bytes:
movw %ax,(%edi)
xorl %eax,%eax
addl $2,%edi
jmp .LStrCopyByte
.LStrCopyWord:
movw %ax,(%edi)
jmp .LStrCopyDone
.LStrCopyByte:
movb %al,(%edi)
.LStrCopyDone:
movl dest,%eax
end ['EAX','ECX','ESI','EDI'];
@ -243,25 +267,78 @@ end ['EAX','ECX','ESI','EDI'];
function strscan(p : pchar;c : char) : pchar;assembler;
asm
xorl %eax,%eax
movl p,%edi
orl %edi,%edi
movl p,%eax
xorl %ecx,%ecx
testl %eax,%eax
jz .LSTRSCAN
movl $0xffffffff,%ecx
cld
repne
scasb
not %ecx
movb c,%al
// align
movb c,%cl
movl %eax,%esi
andl $0xfffffff8,%eax
movl $0xff,%edx
movl p,%edi
repne
scasb
movl $0,%eax
jnz .LSTRSCAN
subl %eax,%esi
jz .LSTRSCANLOOP
.LSTRSCANALIGNLOOP:
movb (%edi),%al
// at .LSTRSCANFOUND, one is substracted from edi to calculate the position,
// so add 1 here already (not after .LSTRSCAN, because then the test/jz and
// cmp/je can't be paired)
incl %edi
testb %al,%al
jz .LSTRSCAN
cmpb %cl,%al
je .LSTRSCANFOUND
decl %esi
jnz .LSTRSCANALIGNLOOP
jmp .LSTRSCANLOOP
.align 16
.LSTRSCANLOOP:
movl (%edi),%eax
movl %eax,%esi
// first char
andl %edx,%eax
// end of string -> stop
jz .LSTRSCAN
shrl $8,%esi
cmpl %ecx,%eax
movl %esi,%eax
je .LSTRSCANFOUND1
// second char
andl %edx,%eax
jz .LSTRSCAN
shrl $8,%esi
cmpl %ecx,%eax
movl %esi,%eax
je .LSTRSCANFOUND2
// third char
andl %edx,%eax
jz .LSTRSCAN
shrl $8,%esi
cmpl %ecx,%eax
movl %esi,%eax
je .LSTRSCANFOUND3
// fourth char
// all upper bits have already been cleared
testl %eax,%eax
jz .LSTRSCAN
addl $4,%edi
cmpl %ecx,%eax
je .LSTRSCANFOUND
jmp .LSTRSCANLOOP
.LSTRSCANFOUND3:
leal 2(%edi),%eax
jmp .LSTRSCAN
.LSTRSCANFOUND2:
leal 1(%edi),%eax
jmp .LSTRSCAN
.LSTRSCANFOUND1:
movl %edi,%eax
decl %eax
jmp .LSTRSCAN
.LSTRSCANFOUND:
leal -1(%edi),%eax
.LSTRSCAN:
end ['EAX','ECX','EDI'];
end ['EAX','ECX','ESI','EDI','EDX'];
function strrscan(p : pchar;c : char) : pchar;assembler;
@ -337,7 +414,10 @@ end ['EAX','ESI','EDI'];
{
$Log$
Revision 1.8 2000-03-28 11:14:33 jonas
Revision 1.9 2000-06-11 14:25:23 jonas
* much faster strcopy and strscan procedures
Revision 1.8 2000/03/28 11:14:33 jonas
* added missing register that is destroyed by strecopy
+ some destroyed register lists for procedures that didn't have one yet