fpc/rtl/powerpc/strings.inc
2002-09-11 07:49:40 +00:00

481 lines
15 KiB
PHP

{
$Id$
This file is part of the Free Pascal run time library.
Copyright (c) 2000 by Jonas Maebe, member of the
Free Pascal development team
Processor dependent part of strings.pp, that can be shared with
sysutils unit.
See the file COPYING.FPC, included in this distribution,
for details about the copyright.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
**********************************************************************}
{ Note: the implementation of these routines is for BIG ENDIAN only!! (JM) }
function strcopy(dest,source : pchar) : pchar;assembler;
{ in: dest in r3, source in r4 }
{ out: result (dest) in r3 }
asm
{ in: dest in r3, source in r4 }
{ out: result (dest) in r3 }
{ load the begin of the source string in the data cache }
dcbt 0,r4
{ get # of misaligned bytes }
rlwinm. r10,r4,0,31-2+1,31
subfic r10,r10,4
mtctr r10
{ since we have to return dest intact, use another register for }
{ dest in the copy loop }
subi r9,r3,1
subi r4,r4,1
beq LStrCopyAligned
LStrCopyAlignLoop:
{ load next byte }
lbzu r0,1(r4)
{ end of string? }
cmplwi cr0,r0,0
{ store byte }
stbu r0,1(r9)
{ loop if misaligned bytes left and not end of string found }
bdnzf eq,LStrCopyAlignLoop
beq LStrCopyDone
LStrCopyAligned:
subi r4,r4,3
subi r9,r9,3
{ setup magic constants }
lis r8,(0xfefefeff)@ha
addi r8,r8,(0xfefefeff)@l
lis r7,(0x80808080)@ha
addi r7,r7,(0x80808080)@l
{
li r8,-257 { 0x0feff }
andis. r8,r8,0x0fefe
li r7,-32640 { 0x08080 }
andis. r7,r7,0x08080
}
{ load first 4 bytes }
lwzu r0,4(r4)
LStrCopyAlignedLoop:
{ test for zero byte }
add r10,r0,r8
andc r10,r10,r0
and. r10,r10,r7
bne LStrCopyEndFound
stwu r0,4(r9)
{ load next 4 bytes (do it here so the load can begin while the }
{ the branch is processed) }
lwzu r0,4(r4)
b LStrCopyAlignedLoop
LStrCopyEndFound:
{ result is either 0, 8, 16 or 24 depending on which byte is zero }
cntlzw r10,r10
addi r9,r9,3
LStrCopyWrapUpLoop:
subi r10,r10,8
rlwinm r0,r0,8,0,31
stbu r0,1(r9)
bge LStrCopyWrapUpLoop
LStrCopyDone:
{ r3 still contains dest here }
end ['R4','R7','R8','R0','R9','R10','CR0','CTR'];
function strecopy(dest,source : pchar) : pchar;assembler;
{ in: dest in r3, source in r4 }
{ out: result (end of new dest) in r3 }
asm
{ load the begin of the source string in the data cache }
dcbt 0,r4
{ get # of misaligned bytes }
rlwinm. r10,r4,0,31-2+1,31
subfic r10,r10,4
mtctr r10
subi r3,r3,1
subi r4,r4,1
beq LStrECopyAligned
LStrECopyAlignLoop:
{ load next byte }
lbzu r0,1(r4)
{ end of string? }
cmplwi cr0,r0,0
{ store byte }
stbu r0,1(r3)
{ loop if misaligned bytes left and not end of string found }
bdnzf eq,LStrECopyAlignLoop
beq LStrECopyDone
LStrECopyAligned:
subi r4,r4,3
subi r3,r3,3
{ setup magic constants }
lis r8,(0xfefefeff)@ha
addi r8,r8,(0xfefefeff)@l
lis r7,(0x80808080)@ha
addi r7,r7,(0x80808080)@l
{
li r8,-257 { 0x0feff }
andis. r8,r8,0x0fefe
li r9,-32640 { 0x08080 }
andis. r9,r9,0x08080
}
LStrECopyAlignedLoop:
{ load next 4 bytes }
lwzu r0,4(r4)
{ test for zero byte }
add r10,r0,r8
andc r10,r10,r0
and. r10,r10,r9
bne LStrECopyEndFound
stwu r0,4(r3)
b LStrECopyAlignedLoop
LStrECopyEndFound:
{ result is either 0, 8, 16 or 24 depending on which byte is zero }
cntlzw r10,r10
addi r3,r3,3
LStrECopyWrapUpLoop:
subic. r10,r10,8
rlwinm r0,r0,8,0,31
stbu r0,1(r3)
bge LStrECopyWrapUpLoop
LStrECopyDone:
{ r3 contains new dest here }
end ['R3','R4','R8','R0','R3','R9','R10','CR0','CTR'];
function strlcopy(dest,source : pchar;maxlen : longint) : pchar;assembler;
{ in: dest in r3, source in r4, maxlen in r5 }
{ out: result (dest) in r3 }
asm
{ load the begin of the source string in the data cache }
dcbt 0,r4
mtctr r5
subi r4,r4,1
subi r10,r3,1
LStrlCopyLoop:
lbzu r0,1(r4)
cmplwi r0,0
stbu r0,1(r10)
bdnzf cr0*4+eq, LStrlCopyLoop
{ if we stopped because we copied a #0, we're done }
beq LStrlCopyDone
{ otherwise add the #0 }
li r0,0
stb r0,1(r10)
LStrlCopyDone:
end ['R0','R4','R10','CR0'];
function strlen(p : pchar) : longint;assembler;
{$i strlen.inc}
function strend(p : pchar) : pchar;assembler;
{ in: p in r3 }
{ out: result (end of p) in r3 }
asm
{ load the begin of the string in the data cache }
dcbt 0,r3
{ empty/invalid string? }
cmplwi r3,0
{ if yes, do nothing }
beq LStrEndDone
subi r3,r3,1
LStrEndLoop:
lbzu r0,1(r3)
cmplwi r0,0
bne LStrEndLoop
LStrEndDone:
end ['R0','R3','R4','CR0'];
function strcomp(str1,str2 : pchar) : longint;assembler;
{ in: str1 in r3, str2 in r4 }
{ out: result (= 0 if strings equal, < 0 if str1 < str2, > 0 if str1 > str2 }
{ in r3 }
asm
{ use r0 instead of r3 for str1 since r3 contains result }
subi r9,r3,1
subi r4,r4,1
LStrCompLoop:
{ load next chars }
lbzu r0,1(r9)
{ check if one is zero }
cmplwi cr1,r0,0
lbzu r10,1(r4)
{ calculate difference }
sub. r3,r0,r10
{ if chars not equal, we're ready }
bne LStrCompDone
{ if they are equal and one is zero, then the other one is zero too }
{ and we're done as well (r3 also contains 0 then) }
{ otherwise loop }
bne cr1,LStrCompLoop
LStrCompDone:
end ['R0','R3','R4','R9','R10','CR0','CR1'];
function strlcomp(str1,str2 : pchar;l : longint) : longint;assembler;
{ (same as strcomp, but maximally compare until l'th character) }
{ in: str1 in r3, str2 in r4, l in r5 }
{ out: result (= 0 if strings equal, < 0 if str1 < str2, > 0 if str1 > str2 }
{ in r3 }
asm
{ load the begin of one of the strings in the data cache }
dcbt 0,r3
{ use r0 instead of r3 for str1 since r3 contains result }
cmplwi r5,0
subi r9,r3,1
li r3,0
beq LStrlCompDone
mtctr r5
subi r4,r4,1
LStrlCompLoop:
{ load next chars }
lbzu r0,1(r9)
{ check if one is zero }
cmplwi cr1,r0,0
lbzu r10,1(r4)
{ calculate difference }
sub. r3,r0,r10
{ if chars not equal, we're ready }
bne LStrlCompDone
{ if they are equal and one is zero, then the other one is zero too }
{ and we're done as well (r3 also contains 0 then) }
{ otherwise loop (if ctr <> 0) }
bdnzf cr1*4+eq,LStrlCompLoop
LStrlCompDone:
end ['R0','R3','R4','R9','R10','CR0','CR1','CTR'];
function stricomp(str1,str2 : pchar) : longint;assembler;
{ in: str1 in r3, str2 in r4 }
{ out: result of case insensitive comparison (< 0, = 0, > 0) }
asm
{ use r28 instead of r3 for str1 since r3 contains result }
subi r28,r3,1
subi r4,r4,1
LStriCompLoop:
{ load next chars }
lbzu r29,1(r28)
{ check if one is zero }
cmplwi cr1,r29,0
lbzu r30,1(r4)
{ calculate difference }
sub. r3,r29,r30
{ if chars are equal, no further test is necessary }
beq+ LStriCompEqual
{ make both lowercase, no branches }
li r27,0
li r25,0
{ r3 := r29 - 'A' }
subic r3,r29,'A'
{ if r29 < 'A' then r27 := 0 else r27 := $ffffffff }
addme r27,r27
{ same for r30 }
subic r3,r30,'A'
addme r25,r25
{ r3 := 'Z' - r29 }
subfic r3,r29,'Z'
{ if r29 < 'A' then r27 := 0 else r27 := $20 }
andi. r27,r27,0x020
{ if r29 > Z then r26 := 0 else r26 := $ffffffff }
subfe r26,r26,r26
{ same for r30 }
subfic r3,r30,'Z'
andi. r25,r25,0x020
subfe r24,r24,r24
{ if (r29 in ['A'..'Z'] then r27 := $20 else r27 := 0 }
and r27,r27,r26
{ same for r30 }
and r25,r25,r24
{ make lowercase }
add r29,r29,r27
{ same for r30 }
add r30,r30,r25
{ compare again }
sub. r3,r29,r30
bne LStriCompDone
LStriCompEqual:
{ if they are equal and one is zero, then the other one is zero too }
{ and we're done as well (r3 also contains 0 then) }
{ otherwise loop }
bne cr1,LStriCompLoop
LStriCompDone:
end ['R3','R4','R26','R27','R28','R29','R30','CR0','CR1'];
function strlicomp(str1,str2 : pchar;l : longint) : longint;assembler;
{ (same as stricomp, but maximally compare until l'th character) }
{ in: str1 in r3, str2 in r4, l in r5 }
{ out: result of case insensitive comparison (< 0, = 0, > 0) }
asm
{ load the begin of one of the string in the data cache }
dcbt 0,r3
{ use r0 instead of r3 for str1 since r3 contains result }
cmplwi r5,0
subi r9,r3,1
li r3,0
beq- LStrliCompDone
mtctr r5
subi r4,r4,1
LStrliCompLoop:
{ load next chars }
lbzu r0,1(r9)
{ check if one is zero }
cmplwi cr1,r0,0
lbzu r10,1(r4)
{ calculate difference }
sub. r3,r0,r10
{ if chars are equal, no further test is necessary }
beq LStrliCompEqual
{ see stricomp for explanation }
li r8,0
li r5,0
subic r3,r0,'A'
addme r8,r8
subic r3,r10,'A'
addme r5,r5
subfic r3,r0,'Z'
andi. r8,r8,0x020
subfe r7,r7,r7
subfic r3,r10,'Z'
andi. r5,r5,0x020
subfe r24,r24,r24
and r8,r8,r7
and r5,r5,r24
add r0,r0,r8
add r10,r10,r5
{ compare again }
sub. r3,r0,r10
bne LStrliCompDone
LStrliCompEqual:
{ if they are equal and one is zero, then the other one is zero too }
{ and we're done as well (r3 also contains 0 then) }
{ otherwise loop (if ctr <> 0) }
bdnzf cr1*4+eq,LStrliCompLoop
LStrliCompDone:
end ['R0','R3','R4','R5','R7','R8','R9','R10','CR0','CR1','CTR'];
function strscan(p : pchar;c : char) : pchar;assembler;
asm
{ empty/invalid string? }
cmplwi r3,0
{ if yes, do nothing }
beq LStrScanDone
subi r3,r3,1
LStrScanLoop:
lbzu r0,1(r3)
cmplw cr1,r0,r4
cmplwi r0,0
beq cr1,LStrScanDone
bne LStrScanLoop
LStrScanDone:
end ['R0','R3','R4','CR0','CR1'];
function strrscan(p : pchar;c : char) : pchar;assembler;
asm
{ empty/invalid string? }
cmplwi r3,0
{ if yes, do nothing }
beq LStrrScanDone
{ make r0 $ffffffff, later on we take min(r0,r3) }
li r0,-1
subi r3,r3,1
LStrrScanLoop:
lbzu r10,1(r3)
cmplw cr1,r10,r4
cmplwi cr0,r10,0
bne+ cr1,LStrrScanNotFound
{ store address of found position }
mr r0,r3
LStrrScanNotFound:
bne LStrrScanLoop
{ Select min of r3 and r0 -> end of string or found position }
{ From the PPC compiler writer's guide, not sure if I could ever }
{ come up with something like this :) }
subfc r10,r3,r0 { r10 = r0 - r3, CA = (r0 >= r3) ? 1 : 0 }
subfe r0,r0,r0 { r0' = (r0 >= r3) ? 0 : -1 }
and r10,r10,r0 { r10 = (r0 >= r3) ? 0 : r0 - r3 }
add r3,r10,r3 { r3 = (r0 >= r3) ? r3 : r0 }
LStrrScanDone:
end ['R0','R3','R4','R10','CR0','CR1'];
function strupper(p : pchar) : pchar;assembler;
asm
cmplwi r3,0
beq LStrUpperNil
subi r9,r3,1
LStrUpperLoop:
lbzu r10,1(r9)
{ a <= x <= b <=> cardinal(x-a) <= cardinal(b-a) }
subi r0,r10,97
cmplwi r0,122-97
cmplwi cr1,r10,0
subi r10,r10,0x20
bgt LStrUpper1
stb r10,0(r9)
LStrUpper1:
bne cr1,LStrUpperLoop
LStrUpperNil:
end ['R0','R9','R10','CR0','CR1'];
function strlower(p : pchar) : pchar;assembler;
asm
cmplwi r3,0
beq LStrLowerNil
subi r9,r3,1
LStrLowerLoop:
lbzu r10,1(r9)
{ a <= x <= b <=> cardinal(x-a) <= cardinal(b-a) }
subi r0,r10,65
cmplwi r0,90-65
cmplwi cr1,r10,0
addi r10,r10,0x20
bgt LStrLower1
stb r10,0(r9)
LStrLower1:
bne cr1,LStrLowerLoop
LStrLowerNil:
end ['R0','R9','R10','CR0','CR1'];
{
$Log$
Revision 1.14 2002-09-11 07:49:40 jonas
* fixed assembler errors
Revision 1.13 2002/09/07 16:01:26 peter
* old logs removed and tabs fixed
Revision 1.12 2002/09/06 16:58:43 jonas
* fixed wrong references (used r0 as base register)
Revision 1.11 2002/08/10 17:14:36 jonas
* various fixes, mostly changing the names of the modifies registers to
upper case since that seems to be required by the compiler
}