x86-64: Update strlen.S to support wcslen/wcsnlen
The difference between strlen and wcslen is byte vs int. We can replace pminub and pcmpeqb with pminud and pcmpeqd to turn strlen into wcslen. * sysdeps/x86_64/strlen.S (PMINU): New. (PCMPEQ): Likewise. (SHIFT_RETURN): Likewise. (FIND_ZERO): Replace pcmpeqb with PCMPEQ. (strlen): Add SHIFT_RETURN before ret. Replace pcmpeqb and pminub with PCMPEQ and PMINU. * sysdeps/x86_64/wcsnlen.S: New file.
This commit is contained in:
H.J. Lu
parent
7395928b95
commit
30cb625a21
10
ChangeLog
10
ChangeLog
|
|
@ -1,3 +1,13 @@
|
|||
2017-06-05 H.J. Lu <hongjiu.lu@intel.com>
|
||||
|
||||
* sysdeps/x86_64/strlen.S (PMINU): New.
|
||||
(PCMPEQ): Likewise.
|
||||
(SHIFT_RETURN): Likewise.
|
||||
(FIND_ZERO): Replace pcmpeqb with PCMPEQ.
|
||||
(strlen): Add SHIFT_RETURN before ret. Replace pcmpeqb and
|
||||
pminub with PCMPEQ and PMINU.
|
||||
* sysdeps/x86_64/wcsnlen.S: New file.
|
||||
|
||||
2017-06-05 H.J. Lu <hongjiu.lu@intel.com>
|
||||
|
||||
* sysdeps/x86_64/memrchr.S (__memrchr): Use 32-bit registers for
|
||||
|
|
|
|||
|
|
@ -1,4 +1,4 @@
|
|||
/* SSE2 version of strlen.
|
||||
/* SSE2 version of strlen/wcslen.
|
||||
Copyright (C) 2012-2017 Free Software Foundation, Inc.
|
||||
This file is part of the GNU C Library.
|
||||
|
||||
|
|
@ -18,6 +18,16 @@
|
|||
|
||||
#include <sysdep.h>
|
||||
|
||||
#ifdef AS_WCSLEN
|
||||
# define PMINU pminud
|
||||
# define PCMPEQ pcmpeqd
|
||||
# define SHIFT_RETURN shrq $2, %rax
|
||||
#else
|
||||
# define PMINU pminub
|
||||
# define PCMPEQ pcmpeqb
|
||||
# define SHIFT_RETURN
|
||||
#endif
|
||||
|
||||
/* Long lived register in strlen(s), strnlen(s, n) are:
|
||||
|
||||
%xmm3 - zero
|
||||
|
|
@ -32,10 +42,10 @@ ENTRY(strlen)
|
|||
|
||||
/* Test 64 bytes from %rax for zero. Save result as bitmask in %rdx. */
|
||||
#define FIND_ZERO \
|
||||
pcmpeqb (%rax), %xmm0; \
|
||||
pcmpeqb 16(%rax), %xmm1; \
|
||||
pcmpeqb 32(%rax), %xmm2; \
|
||||
pcmpeqb 48(%rax), %xmm3; \
|
||||
PCMPEQ (%rax), %xmm0; \
|
||||
PCMPEQ 16(%rax), %xmm1; \
|
||||
PCMPEQ 32(%rax), %xmm2; \
|
||||
PCMPEQ 48(%rax), %xmm3; \
|
||||
pmovmskb %xmm0, %esi; \
|
||||
pmovmskb %xmm1, %edx; \
|
||||
pmovmskb %xmm2, %r8d; \
|
||||
|
|
@ -54,6 +64,9 @@ ENTRY(strlen)
|
|||
xor %rax, %rax
|
||||
ret
|
||||
L(n_nonzero):
|
||||
# ifdef AS_WCSLEN
|
||||
shlq $2, %rsi
|
||||
# endif
|
||||
|
||||
/* Initialize long lived registers. */
|
||||
|
||||
|
|
@ -96,6 +109,7 @@ L(n_nonzero):
|
|||
test %rdx, %rdx; \
|
||||
je L(lab); \
|
||||
bsfq %rdx, %rax; \
|
||||
SHIFT_RETURN; \
|
||||
ret
|
||||
|
||||
#ifdef AS_STRNLEN
|
||||
|
|
@ -104,19 +118,20 @@ L(n_nonzero):
|
|||
#else
|
||||
/* Test first 16 bytes unaligned. */
|
||||
movdqu (%rax), %xmm4
|
||||
pcmpeqb %xmm0, %xmm4
|
||||
PCMPEQ %xmm0, %xmm4
|
||||
pmovmskb %xmm4, %edx
|
||||
test %edx, %edx
|
||||
je L(next48_bytes)
|
||||
bsf %edx, %eax /* If eax is zeroed 16bit bsf can be used. */
|
||||
SHIFT_RETURN
|
||||
ret
|
||||
|
||||
L(next48_bytes):
|
||||
/* Same as FIND_ZERO except we do not check first 16 bytes. */
|
||||
andq $-16, %rax
|
||||
pcmpeqb 16(%rax), %xmm1
|
||||
pcmpeqb 32(%rax), %xmm2
|
||||
pcmpeqb 48(%rax), %xmm3
|
||||
PCMPEQ 16(%rax), %xmm1
|
||||
PCMPEQ 32(%rax), %xmm2
|
||||
PCMPEQ 48(%rax), %xmm3
|
||||
pmovmskb %xmm1, %edx
|
||||
pmovmskb %xmm2, %r8d
|
||||
pmovmskb %xmm3, %ecx
|
||||
|
|
@ -145,6 +160,7 @@ L(strnlen_ret):
|
|||
test %rdx, %rdx
|
||||
je L(loop_init)
|
||||
bsfq %rdx, %rax
|
||||
SHIFT_RETURN
|
||||
ret
|
||||
#endif
|
||||
.p2align 4
|
||||
|
|
@ -161,10 +177,10 @@ L(loop):
|
|||
je L(exit_end)
|
||||
|
||||
movdqa (%rax), %xmm0
|
||||
pminub 16(%rax), %xmm0
|
||||
pminub 32(%rax), %xmm0
|
||||
pminub 48(%rax), %xmm0
|
||||
pcmpeqb %xmm3, %xmm0
|
||||
PMINU 16(%rax), %xmm0
|
||||
PMINU 32(%rax), %xmm0
|
||||
PMINU 48(%rax), %xmm0
|
||||
PCMPEQ %xmm3, %xmm0
|
||||
pmovmskb %xmm0, %edx
|
||||
testl %edx, %edx
|
||||
jne L(exit)
|
||||
|
|
@ -182,6 +198,7 @@ L(first):
|
|||
bsfq %rdx, %rdx
|
||||
addq %rdx, %rax
|
||||
subq %rdi, %rax
|
||||
SHIFT_RETURN
|
||||
ret
|
||||
|
||||
.p2align 4
|
||||
|
|
@ -192,6 +209,7 @@ L(exit):
|
|||
bsfq %rdx, %rdx
|
||||
addq %rdx, %rax
|
||||
subq %rdi, %rax
|
||||
SHIFT_RETURN
|
||||
ret
|
||||
|
||||
#else
|
||||
|
|
@ -201,10 +219,10 @@ L(exit):
|
|||
L(loop):
|
||||
|
||||
movdqa 64(%rax), %xmm0
|
||||
pminub 80(%rax), %xmm0
|
||||
pminub 96(%rax), %xmm0
|
||||
pminub 112(%rax), %xmm0
|
||||
pcmpeqb %xmm3, %xmm0
|
||||
PMINU 80(%rax), %xmm0
|
||||
PMINU 96(%rax), %xmm0
|
||||
PMINU 112(%rax), %xmm0
|
||||
PCMPEQ %xmm3, %xmm0
|
||||
pmovmskb %xmm0, %edx
|
||||
testl %edx, %edx
|
||||
jne L(exit64)
|
||||
|
|
@ -212,10 +230,10 @@ L(loop):
|
|||
subq $-128, %rax
|
||||
|
||||
movdqa (%rax), %xmm0
|
||||
pminub 16(%rax), %xmm0
|
||||
pminub 32(%rax), %xmm0
|
||||
pminub 48(%rax), %xmm0
|
||||
pcmpeqb %xmm3, %xmm0
|
||||
PMINU 16(%rax), %xmm0
|
||||
PMINU 32(%rax), %xmm0
|
||||
PMINU 48(%rax), %xmm0
|
||||
PCMPEQ %xmm3, %xmm0
|
||||
pmovmskb %xmm0, %edx
|
||||
testl %edx, %edx
|
||||
jne L(exit0)
|
||||
|
|
@ -231,6 +249,7 @@ L(exit0):
|
|||
bsfq %rdx, %rdx
|
||||
addq %rdx, %rax
|
||||
subq %rdi, %rax
|
||||
SHIFT_RETURN
|
||||
ret
|
||||
|
||||
#endif
|
||||
|
|
|
|||
|
|
@ -0,0 +1,7 @@
|
|||
#define AS_WCSLEN
|
||||
#define AS_STRNLEN
|
||||
#define strlen __wcsnlen
|
||||
|
||||
#include "strlen.S"
|
||||
|
||||
weak_alias(__wcsnlen, wcsnlen)
|
||||
Loading…
Reference in New Issue