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authorH.J. Lu <hjl.tools@gmail.com>2017-05-30 12:39:14 -0700
committerH.J. Lu <hjl.tools@gmail.com>2017-05-30 12:39:14 -0700
commit4f26ef1b67287d1f2c32865f7d79c13abda81915 (patch)
treebc9cb0c0b5c581cee6aba4f2fc138b48783ab565 /sysdeps/x86_64
parent542a34783ce1cfc63929ec50ab1f9f738711b815 (diff)
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x86_64: Remove redundant REX bytes from memchr.S
By x86-64 specification, 32-bit destination registers are zero-extended to 64 bits. There is no need to use 64-bit registers when only the lower 32 bits are non-zero. * sysdeps/x86_64/memchr.S (MEMCHR): Use 32-bit registers for the lower 32 bits.
Diffstat (limited to 'sysdeps/x86_64')
-rw-r--r--sysdeps/x86_64/memchr.S28
1 files changed, 14 insertions, 14 deletions
diff --git a/sysdeps/x86_64/memchr.S b/sysdeps/x86_64/memchr.S
index f82e1c5bf7..d3be012424 100644
--- a/sysdeps/x86_64/memchr.S
+++ b/sysdeps/x86_64/memchr.S
@@ -22,18 +22,18 @@
.text
ENTRY(memchr)
- movd %rsi, %xmm1
- mov %rdi, %rcx
+ movd %esi, %xmm1
+ mov %edi, %ecx
punpcklbw %xmm1, %xmm1
test %rdx, %rdx
jz L(return_null)
punpcklbw %xmm1, %xmm1
- and $63, %rcx
+ and $63, %ecx
pshufd $0, %xmm1, %xmm1
- cmp $48, %rcx
+ cmp $48, %ecx
ja L(crosscache)
movdqu (%rdi), %xmm0
@@ -45,7 +45,7 @@ ENTRY(memchr)
sub $16, %rdx
jbe L(return_null)
add $16, %rdi
- and $15, %rcx
+ and $15, %ecx
and $-16, %rdi
add %rcx, %rdx
sub $64, %rdx
@@ -54,7 +54,7 @@ ENTRY(memchr)
.p2align 4
L(crosscache):
- and $15, %rcx
+ and $15, %ecx
and $-16, %rdi
movdqa (%rdi), %xmm0
@@ -148,7 +148,7 @@ L(loop_prolog):
mov %rdi, %rcx
and $-64, %rdi
- and $63, %rcx
+ and $63, %ecx
add %rcx, %rdx
.p2align 4
@@ -200,7 +200,7 @@ L(align64_loop):
.p2align 4
L(exit_loop):
- add $32, %rdx
+ add $32, %edx
jle L(exit_loop_32)
movdqa (%rdi), %xmm0
@@ -220,32 +220,32 @@ L(exit_loop):
pmovmskb %xmm3, %eax
test %eax, %eax
jnz L(matches32_1)
- sub $16, %rdx
+ sub $16, %edx
jle L(return_null)
pcmpeqb 48(%rdi), %xmm1
pmovmskb %xmm1, %eax
test %eax, %eax
jnz L(matches48_1)
- xor %rax, %rax
+ xor %eax, %eax
ret
.p2align 4
L(exit_loop_32):
- add $32, %rdx
+ add $32, %edx
movdqa (%rdi), %xmm0
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm0, %eax
test %eax, %eax
jnz L(matches_1)
- sub $16, %rdx
+ sub $16, %edx
jbe L(return_null)
pcmpeqb 16(%rdi), %xmm1
pmovmskb %xmm1, %eax
test %eax, %eax
jnz L(matches16_1)
- xor %rax, %rax
+ xor %eax, %eax
ret
.p2align 4
@@ -306,7 +306,7 @@ L(matches48_1):
.p2align 4
L(return_null):
- xor %rax, %rax
+ xor %eax, %eax
ret
END(memchr)