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authorH.J. Lu <hjl.tools@gmail.com>2015-08-25 08:51:09 -0700
committerH.J. Lu <hjl.tools@gmail.com>2015-08-25 08:51:23 -0700
commit2194737e77256a847ed4fca7652e4dcb8d3f9c1e (patch)
treea603bcd4140c67d443ac8154a98cca8213e220c2
parent2339c6f4bd71b1e4dfcb2a05a9200cd68d3d8837 (diff)
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Replace %xmm[8-12] with %xmm[0-4]
Since ld.so preserves vector registers now, we can use %xmm[0-4] to avoid the REX prefix. * sysdeps/x86_64/strlen.S: Replace %xmm[8-12] with %xmm[0-4].
-rw-r--r--ChangeLog4
-rw-r--r--sysdeps/x86_64/strlen.S94
2 files changed, 51 insertions, 47 deletions
diff --git a/ChangeLog b/ChangeLog
index cdecbea..a442ee1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
2015-08-25 H.J. Lu <hongjiu.lu@intel.com>
+ * sysdeps/x86_64/strlen.S: Replace %xmm[8-12] with %xmm[0-4].
+
+2015-08-25 H.J. Lu <hongjiu.lu@intel.com>
+
* sysdeps/x86_64/rtld-memcmp.c: Removed.
* sysdeps/x86_64/rtld-memset.S: Likewise.
* sysdeps/x86_64/rtld-strchr.S: Likewise.
diff --git a/sysdeps/x86_64/strlen.S b/sysdeps/x86_64/strlen.S
index c382c8d..0725333 100644
--- a/sysdeps/x86_64/strlen.S
+++ b/sysdeps/x86_64/strlen.S
@@ -20,7 +20,7 @@
/* Long lived register in strlen(s), strnlen(s, n) are:
- %xmm11 - zero
+ %xmm3 - zero
%rdi - s
%r10 (s+n) & (~(64-1))
%r11 s+n
@@ -32,14 +32,14 @@ ENTRY(strlen)
/* Test 64 bytes from %rax for zero. Save result as bitmask in %rdx. */
#define FIND_ZERO \
- pcmpeqb (%rax), %xmm8; \
- pcmpeqb 16(%rax), %xmm9; \
- pcmpeqb 32(%rax), %xmm10; \
- pcmpeqb 48(%rax), %xmm11; \
- pmovmskb %xmm8, %esi; \
- pmovmskb %xmm9, %edx; \
- pmovmskb %xmm10, %r8d; \
- pmovmskb %xmm11, %ecx; \
+ pcmpeqb (%rax), %xmm0; \
+ pcmpeqb 16(%rax), %xmm1; \
+ pcmpeqb 32(%rax), %xmm2; \
+ pcmpeqb 48(%rax), %xmm3; \
+ pmovmskb %xmm0, %esi; \
+ pmovmskb %xmm1, %edx; \
+ pmovmskb %xmm2, %r8d; \
+ pmovmskb %xmm3, %ecx; \
salq $16, %rdx; \
salq $16, %rcx; \
orq %rsi, %rdx; \
@@ -63,10 +63,10 @@ L(n_nonzero):
mov %rsi, %r11
#endif
- pxor %xmm8, %xmm8
- pxor %xmm9, %xmm9
- pxor %xmm10, %xmm10
- pxor %xmm11, %xmm11
+ pxor %xmm0, %xmm0
+ pxor %xmm1, %xmm1
+ pxor %xmm2, %xmm2
+ pxor %xmm3, %xmm3
movq %rdi, %rax
movq %rdi, %rcx
andq $4095, %rcx
@@ -103,9 +103,9 @@ L(n_nonzero):
FIND_ZERO
#else
/* Test first 16 bytes unaligned. */
- movdqu (%rax), %xmm12
- pcmpeqb %xmm8, %xmm12
- pmovmskb %xmm12, %edx
+ movdqu (%rax), %xmm4
+ pcmpeqb %xmm0, %xmm4
+ pmovmskb %xmm4, %edx
test %edx, %edx
je L(next48_bytes)
bsf %edx, %eax /* If eax is zeroed 16bit bsf can be used. */
@@ -114,12 +114,12 @@ L(n_nonzero):
L(next48_bytes):
/* Same as FIND_ZERO except we do not check first 16 bytes. */
andq $-16, %rax
- pcmpeqb 16(%rax), %xmm9
- pcmpeqb 32(%rax), %xmm10
- pcmpeqb 48(%rax), %xmm11
- pmovmskb %xmm9, %edx
- pmovmskb %xmm10, %r8d
- pmovmskb %xmm11, %ecx
+ pcmpeqb 16(%rax), %xmm1
+ pcmpeqb 32(%rax), %xmm2
+ pcmpeqb 48(%rax), %xmm3
+ pmovmskb %xmm1, %edx
+ pmovmskb %xmm2, %r8d
+ pmovmskb %xmm3, %ecx
salq $16, %rdx
salq $16, %rcx
orq %r8, %rcx
@@ -127,7 +127,7 @@ L(next48_bytes):
orq %rcx, %rdx
#endif
- /* When no zero byte is found xmm9-11 are zero so we do not have to
+ /* When no zero byte is found xmm1-3 are zero so we do not have to
zero them. */
PROLOG(loop)
@@ -149,9 +149,9 @@ L(strnlen_ret):
#endif
.p2align 4
L(loop_init):
- pxor %xmm9, %xmm9
- pxor %xmm10, %xmm10
- pxor %xmm11, %xmm11
+ pxor %xmm1, %xmm1
+ pxor %xmm2, %xmm2
+ pxor %xmm3, %xmm3
#ifdef AS_STRNLEN
.p2align 4
L(loop):
@@ -160,12 +160,12 @@ L(loop):
cmpq %rax, %r10
je L(exit_end)
- movdqa (%rax), %xmm8
- pminub 16(%rax), %xmm8
- pminub 32(%rax), %xmm8
- pminub 48(%rax), %xmm8
- pcmpeqb %xmm11, %xmm8
- pmovmskb %xmm8, %edx
+ movdqa (%rax), %xmm0
+ pminub 16(%rax), %xmm0
+ pminub 32(%rax), %xmm0
+ pminub 48(%rax), %xmm0
+ pcmpeqb %xmm3, %xmm0
+ pmovmskb %xmm0, %edx
testl %edx, %edx
jne L(exit)
jmp L(loop)
@@ -174,7 +174,7 @@ L(loop):
L(exit_end):
cmp %rax, %r11
je L(first) /* Do not read when end is at page boundary. */
- pxor %xmm8, %xmm8
+ pxor %xmm0, %xmm0
FIND_ZERO
L(first):
@@ -186,7 +186,7 @@ L(first):
.p2align 4
L(exit):
- pxor %xmm8, %xmm8
+ pxor %xmm0, %xmm0
FIND_ZERO
bsfq %rdx, %rdx
@@ -200,23 +200,23 @@ L(exit):
.p2align 4
L(loop):
- movdqa 64(%rax), %xmm8
- pminub 80(%rax), %xmm8
- pminub 96(%rax), %xmm8
- pminub 112(%rax), %xmm8
- pcmpeqb %xmm11, %xmm8
- pmovmskb %xmm8, %edx
+ movdqa 64(%rax), %xmm0
+ pminub 80(%rax), %xmm0
+ pminub 96(%rax), %xmm0
+ pminub 112(%rax), %xmm0
+ pcmpeqb %xmm3, %xmm0
+ pmovmskb %xmm0, %edx
testl %edx, %edx
jne L(exit64)
subq $-128, %rax
- movdqa (%rax), %xmm8
- pminub 16(%rax), %xmm8
- pminub 32(%rax), %xmm8
- pminub 48(%rax), %xmm8
- pcmpeqb %xmm11, %xmm8
- pmovmskb %xmm8, %edx
+ movdqa (%rax), %xmm0
+ pminub 16(%rax), %xmm0
+ pminub 32(%rax), %xmm0
+ pminub 48(%rax), %xmm0
+ pcmpeqb %xmm3, %xmm0
+ pmovmskb %xmm0, %edx
testl %edx, %edx
jne L(exit0)
jmp L(loop)
@@ -225,7 +225,7 @@ L(loop):
L(exit64):
addq $64, %rax
L(exit0):
- pxor %xmm8, %xmm8
+ pxor %xmm0, %xmm0
FIND_ZERO
bsfq %rdx, %rdx