/* Optimized strcasecmp implementation for PowerPC64.
Copyright (C) 2016-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
. */
#include
#include
/* int [r3] strcasecmp (const char *s1 [r3], const char *s2 [r4] ) */
#ifndef USE_AS_STRNCASECMP
# define __STRCASECMP __strcasecmp
# define STRCASECMP strcasecmp
#else
# define __STRCASECMP __strncasecmp
# define STRCASECMP strncasecmp
#endif
/* Convert 16 bytes to lowercase and compare */
#define TOLOWER() \
vaddubm v8, v4, v1; \
vaddubm v7, v4, v3; \
vcmpgtub v8, v8, v2; \
vsel v4, v7, v4, v8; \
vaddubm v8, v5, v1; \
vaddubm v7, v5, v3; \
vcmpgtub v8, v8, v2; \
vsel v5, v7, v5, v8; \
vcmpequb. v7, v5, v4;
/*
* Get 16 bytes for unaligned case.
* reg1: Vector to hold next 16 bytes.
* reg2: Address to read from.
* reg3: Permute control vector.
* v8: Tmp vector used to mask unwanted bytes.
* v9: Tmp vector,0 when null is found on first 16 bytes
*/
#ifdef __LITTLE_ENDIAN__
#define GET16BYTES(reg1, reg2, reg3) \
lvx reg1, 0, reg2; \
vspltisb v8, -1; \
vperm v8, v8, reg1, reg3; \
vcmpequb. v8, v0, v8; \
beq cr6, 1f; \
vspltisb v9, 0; \
b 2f; \
.align 4; \
1: \
addi r6, reg2, 16; \
lvx v9, 0, r6; \
2: \
vperm reg1, v9, reg1, reg3;
#else
#define GET16BYTES(reg1, reg2, reg3) \
lvx reg1, 0, reg2; \
vspltisb v8, -1; \
vperm v8, reg1, v8, reg3; \
vcmpequb. v8, v0, v8; \
beq cr6, 1f; \
vspltisb v9, 0; \
b 2f; \
.align 4; \
1: \
addi r6, reg2, 16; \
lvx v9, 0, r6; \
2: \
vperm reg1, reg1, v9, reg3;
#endif
/* Check null in v4, v5 and convert to lower. */
#define CHECKNULLANDCONVERT() \
vcmpequb. v7, v0, v5; \
beq cr6, 3f; \
vcmpequb. v7, v0, v4; \
beq cr6, 3f; \
b L(null_found); \
.align 4; \
3: \
TOLOWER()
.machine power8
ENTRY (__STRCASECMP)
#ifdef USE_AS_STRNCASECMP
CALL_MCOUNT 3
#else
CALL_MCOUNT 2
#endif
#define rRTN r3 /* Return value */
#define rSTR1 r10 /* 1st string */
#define rSTR2 r4 /* 2nd string */
#define rCHAR1 r6 /* Byte read from 1st string */
#define rCHAR2 r7 /* Byte read from 2nd string */
#define rADDR1 r8 /* Address of tolower(rCHAR1) */
#define rADDR2 r12 /* Address of tolower(rCHAR2) */
#define rLWR1 r8 /* Word tolower(rCHAR1) */
#define rLWR2 r12 /* Word tolower(rCHAR2) */
#define rTMP r9
#define rLOC r11 /* Default locale address */
cmpd cr7, rRTN, rSTR2
/* Get locale address. */
ld rTMP, __libc_tsd_LOCALE@got@tprel(r2)
add rLOC, rTMP, __libc_tsd_LOCALE@tls
ld rLOC, 0(rLOC)
mr rSTR1, rRTN
li rRTN, 0
beqlr cr7
#ifdef USE_AS_STRNCASECMP
cmpdi cr7, r5, 0
beq cr7, L(retnull)
cmpdi cr7, r5, 16
blt cr7, L(bytebybyte)
#endif
vspltisb v0, 0
vspltisb v8, -1
/* Check for null in initial characters.
Check max of 16 char depending on the alignment.
If null is present, proceed byte by byte. */
lvx v4, 0, rSTR1
#ifdef __LITTLE_ENDIAN__
lvsr v10, 0, rSTR1 /* Compute mask. */
vperm v9, v8, v4, v10 /* Mask bits that are not part of string. */
#else
lvsl v10, 0, rSTR1
vperm v9, v4, v8, v10
#endif
vcmpequb. v9, v0, v9 /* Check for null bytes. */
bne cr6, L(bytebybyte)
lvx v5, 0, rSTR2
/* Calculate alignment. */
#ifdef __LITTLE_ENDIAN__
lvsr v6, 0, rSTR2
vperm v9, v8, v5, v6 /* Mask bits that are not part of string. */
#else
lvsl v6, 0, rSTR2
vperm v9, v5, v8, v6
#endif
vcmpequb. v9, v0, v9 /* Check for null bytes. */
bne cr6, L(bytebybyte)
/* Check if locale has non ascii characters. */
ld rTMP, 0(rLOC)
addi r6, rTMP,LOCALE_DATA_VALUES+_NL_CTYPE_NONASCII_CASE*SIZEOF_VALUES
lwz rTMP, 0(r6)
cmpdi cr7, rTMP, 1
beq cr7, L(bytebybyte)
/* Load vector registers with values used for TOLOWER. */
/* Load v1 = 0xbf, v2 = 0x19 v3 = 0x20 in each byte. */
vspltisb v3, 2
vspltisb v9, 4
vsl v3, v3, v9
vaddubm v1, v3, v3
vnor v1, v1, v1
vspltisb v2, 7
vsububm v2, v3, v2
andi. rADDR1, rSTR1, 0xF
beq cr0, L(align)
addi r6, rSTR1, 16
lvx v9, 0, r6
/* Compute 16 bytes from previous two loads. */
#ifdef __LITTLE_ENDIAN__
vperm v4, v9, v4, v10
#else
vperm v4, v4, v9, v10
#endif
L(align):
andi. rADDR2, rSTR2, 0xF
beq cr0, L(align1)
addi r6, rSTR2, 16
lvx v9, 0, r6
/* Compute 16 bytes from previous two loads. */
#ifdef __LITTLE_ENDIAN__
vperm v5, v9, v5, v6
#else
vperm v5, v5, v9, v6
#endif
L(align1):
CHECKNULLANDCONVERT()
blt cr6, L(match)
b L(different)
.align 4
L(match):
clrldi r6, rSTR1, 60
subfic r7, r6, 16
#ifdef USE_AS_STRNCASECMP
sub r5, r5, r7
#endif
add rSTR1, rSTR1, r7
add rSTR2, rSTR2, r7
andi. rADDR2, rSTR2, 0xF
addi rSTR1, rSTR1, -16
addi rSTR2, rSTR2, -16
beq cr0, L(aligned)
#ifdef __LITTLE_ENDIAN__
lvsr v6, 0, rSTR2
#else
lvsl v6, 0, rSTR2
#endif
/* There are 2 loops depending on the input alignment.
Each loop gets 16 bytes from s1 and s2, check for null,
convert to lowercase and compare. Loop till difference
or null occurs. */
L(s1_align):
addi rSTR1, rSTR1, 16
addi rSTR2, rSTR2, 16
#ifdef USE_AS_STRNCASECMP
cmpdi cr7, r5, 16
blt cr7, L(bytebybyte)
addi r5, r5, -16
#endif
lvx v4, 0, rSTR1
GET16BYTES(v5, rSTR2, v6)
CHECKNULLANDCONVERT()
blt cr6, L(s1_align)
b L(different)
.align 4
L(aligned):
addi rSTR1, rSTR1, 16
addi rSTR2, rSTR2, 16
#ifdef USE_AS_STRNCASECMP
cmpdi cr7, r5, 16
blt cr7, L(bytebybyte)
addi r5, r5, -16
#endif
lvx v4, 0, rSTR1
lvx v5, 0, rSTR2
CHECKNULLANDCONVERT()
blt cr6, L(aligned)
/* Calculate and return the difference. */
L(different):
vaddubm v1, v3, v3
vcmpequb v7, v0, v7
#ifdef __LITTLE_ENDIAN__
/* Count trailing zero. */
vspltisb v8, -1
vadduqm v9, v7, v8
vandc v8, v9, v7
vpopcntd v8, v8
vspltb v6, v8, 15
vcmpequb. v6, v6, v1
blt cr6, L(shift8)
#else
/* Count leading zero. */
vclzd v8, v7
vspltb v6, v8, 7
vcmpequb. v6, v6, v1
blt cr6, L(shift8)
vsro v8, v8, v1
#endif
b L(skipsum)
.align 4
L(shift8):
vsumsws v8, v8, v0
L(skipsum):
#ifdef __LITTLE_ENDIAN__
/* Shift registers based on leading zero count. */
vsro v6, v5, v8
vsro v7, v4, v8
/* Merge and move to GPR. */
vmrglb v6, v6, v7
vslo v1, v6, v1
mfvrd r3, v1
/* Place the characters that are different in first position. */
sldi rSTR2, rRTN, 56
srdi rSTR2, rSTR2, 56
sldi rSTR1, rRTN, 48
srdi rSTR1, rSTR1, 56
#else
vslo v6, v5, v8
vslo v7, v4, v8
vmrghb v1, v6, v7
mfvrd r3, v1
srdi rSTR2, rRTN, 48
sldi rSTR2, rSTR2, 56
srdi rSTR2, rSTR2, 56
srdi rSTR1, rRTN, 56
#endif
subf rRTN, rSTR1, rSTR2
extsw rRTN, rRTN
blr
.align 4
/* OK. We've hit the end of the string. We need to be careful that
we don't compare two strings as different because of junk beyond
the end of the strings... */
L(null_found):
vaddubm v10, v3, v3
#ifdef __LITTLE_ENDIAN__
/* Count trailing zero. */
vspltisb v8, -1
vadduqm v9, v7, v8
vandc v8, v9, v7
vpopcntd v8, v8
vspltb v6, v8, 15
vcmpequb. v6, v6, v10
blt cr6, L(shift_8)
#else
/* Count leading zero. */
vclzd v8, v7
vspltb v6, v8, 7
vcmpequb. v6, v6, v10
blt cr6, L(shift_8)
vsro v8, v8, v10
#endif
b L(skipsum1)
.align 4
L(shift_8):
vsumsws v8, v8, v0
L(skipsum1):
/* Calculate shift count based on count of zero. */
vspltisb v10, 7
vslb v10, v10, v10
vsldoi v9, v0, v10, 1
vsubudm v9, v9, v8
vspltisb v8, 8
vsldoi v8, v0, v8, 1
vsubudm v9, v9, v8
/* Shift and remove junk after null character. */
#ifdef __LITTLE_ENDIAN__
vslo v5, v5, v9
vslo v4, v4, v9
#else
vsro v5, v5, v9
vsro v4, v4, v9
#endif
/* Convert and compare 16 bytes. */
TOLOWER()
blt cr6, L(retnull)
b L(different)
.align 4
L(retnull):
li rRTN, 0
blr
.align 4
L(bytebybyte):
/* Unrolling loop for POWER: loads are done with 'lbz' plus
offset and string descriptors are only updated in the end
of loop unrolling. */
ld rLOC, LOCALE_CTYPE_TOLOWER(rLOC)
lbz rCHAR1, 0(rSTR1) /* Load char from s1 */
lbz rCHAR2, 0(rSTR2) /* Load char from s2 */
#ifdef USE_AS_STRNCASECMP
rldicl rTMP, r5, 62, 2
cmpdi cr7, rTMP, 0
beq cr7, L(lessthan4)
mtctr rTMP
#endif
L(loop):
cmpdi rCHAR1, 0 /* *s1 == '\0' ? */
sldi rADDR1, rCHAR1, 2 /* Calculate address for tolower(*s1) */
sldi rADDR2, rCHAR2, 2 /* Calculate address for tolower(*s2) */
lwzx rLWR1, rLOC, rADDR1 /* Load tolower(*s1) */
lwzx rLWR2, rLOC, rADDR2 /* Load tolower(*s2) */
cmpw cr1, rLWR1, rLWR2 /* r = tolower(*s1) == tolower(*s2) ? */
crorc 4*cr1+eq,eq,4*cr1+eq /* (*s1 != '\0') || (r == 1) */
beq cr1, L(done)
lbz rCHAR1, 1(rSTR1)
lbz rCHAR2, 1(rSTR2)
cmpdi rCHAR1, 0
sldi rADDR1, rCHAR1, 2
sldi rADDR2, rCHAR2, 2
lwzx rLWR1, rLOC, rADDR1
lwzx rLWR2, rLOC, rADDR2
cmpw cr1, rLWR1, rLWR2
crorc 4*cr1+eq,eq,4*cr1+eq
beq cr1, L(done)
lbz rCHAR1, 2(rSTR1)
lbz rCHAR2, 2(rSTR2)
cmpdi rCHAR1, 0
sldi rADDR1, rCHAR1, 2
sldi rADDR2, rCHAR2, 2
lwzx rLWR1, rLOC, rADDR1
lwzx rLWR2, rLOC, rADDR2
cmpw cr1, rLWR1, rLWR2
crorc 4*cr1+eq,eq,4*cr1+eq
beq cr1, L(done)
lbz rCHAR1, 3(rSTR1)
lbz rCHAR2, 3(rSTR2)
cmpdi rCHAR1, 0
/* Increment both string descriptors */
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
sldi rADDR1, rCHAR1, 2
sldi rADDR2, rCHAR2, 2
lwzx rLWR1, rLOC, rADDR1
lwzx rLWR2, rLOC, rADDR2
cmpw cr1, rLWR1, rLWR2
crorc 4*cr1+eq,eq,4*cr1+eq
beq cr1, L(done)
lbz rCHAR1, 0(rSTR1) /* Load char from s1 */
lbz rCHAR2, 0(rSTR2) /* Load char from s2 */
#ifdef USE_AS_STRNCASECMP
bdnz L(loop)
#else
b L(loop)
#endif
#ifdef USE_AS_STRNCASECMP
L(lessthan4):
clrldi r5, r5, 62
cmpdi cr7, r5, 0
beq cr7, L(retnull)
mtctr r5
L(loop1):
cmpdi rCHAR1, 0
sldi rADDR1, rCHAR1, 2
sldi rADDR2, rCHAR2, 2
lwzx rLWR1, rLOC, rADDR1
lwzx rLWR2, rLOC, rADDR2
cmpw cr1, rLWR1, rLWR2
crorc 4*cr1+eq,eq,4*cr1+eq
beq cr1, L(done)
addi rSTR1, rSTR1, 1
addi rSTR2, rSTR2, 1
lbz rCHAR1, 0(rSTR1)
lbz rCHAR2, 0(rSTR2)
bdnz L(loop1)
#endif
L(done):
subf r0, rLWR2, rLWR1
extsw rRTN, r0
blr
END (__STRCASECMP)
weak_alias (__STRCASECMP, STRCASECMP)
libc_hidden_builtin_def (__STRCASECMP)