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-rw-r--r--arch/x86_64/lib/memset.S79
1 files changed, 44 insertions, 35 deletions
diff --git a/arch/x86_64/lib/memset.S b/arch/x86_64/lib/memset.S
index ad397f2c7de..09ed1f6b0ea 100644
--- a/arch/x86_64/lib/memset.S
+++ b/arch/x86_64/lib/memset.S
@@ -1,4 +1,9 @@
/* Copyright 2002 Andi Kleen, SuSE Labs */
+
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <asm/dwarf2.h>
+
/*
* ISO C memset - set a memory block to a byte value.
*
@@ -8,11 +13,29 @@
*
* rax original destination
*/
- .globl __memset
- .globl memset
- .p2align 4
-memset:
-__memset:
+ ALIGN
+memset_c:
+ CFI_STARTPROC
+ movq %rdi,%r9
+ movl %edx,%r8d
+ andl $7,%r8d
+ movl %edx,%ecx
+ shrl $3,%ecx
+ /* expand byte value */
+ movzbl %sil,%esi
+ movabs $0x0101010101010101,%rax
+ mulq %rsi /* with rax, clobbers rdx */
+ rep stosq
+ movl %r8d,%ecx
+ rep stosb
+ movq %r9,%rax
+ ret
+ CFI_ENDPROC
+ENDPROC(memset_c)
+
+ENTRY(memset)
+ENTRY(__memset)
+ CFI_STARTPROC
movq %rdi,%r10
movq %rdx,%r11
@@ -25,6 +48,7 @@ __memset:
movl %edi,%r9d
andl $7,%r9d
jnz .Lbad_alignment
+ CFI_REMEMBER_STATE
.Lafter_bad_alignment:
movl %r11d,%ecx
@@ -75,6 +99,7 @@ __memset:
movq %r10,%rax
ret
+ CFI_RESTORE_STATE
.Lbad_alignment:
cmpq $7,%r11
jbe .Lhandle_7
@@ -84,42 +109,26 @@ __memset:
addq %r8,%rdi
subq %r8,%r11
jmp .Lafter_bad_alignment
+.Lfinal:
+ CFI_ENDPROC
+ENDPROC(memset)
+ENDPROC(__memset)
/* Some CPUs run faster using the string instructions.
It is also a lot simpler. Use this when possible */
#include <asm/cpufeature.h>
+ .section .altinstr_replacement,"ax"
+1: .byte 0xeb /* jmp <disp8> */
+ .byte (memset_c - memset) - (2f - 1b) /* offset */
+2:
+ .previous
.section .altinstructions,"a"
.align 8
- .quad memset
- .quad memset_c
- .byte X86_FEATURE_REP_GOOD
- .byte memset_c_end-memset_c
- .byte memset_c_end-memset_c
- .previous
-
- .section .altinstr_replacement,"ax"
- /* rdi destination
- * rsi value
- * rdx count
- */
-memset_c:
- movq %rdi,%r9
- movl %edx,%r8d
- andl $7,%r8d
- movl %edx,%ecx
- shrl $3,%ecx
- /* expand byte value */
- movzbl %sil,%esi
- movabs $0x0101010101010101,%rax
- mulq %rsi /* with rax, clobbers rdx */
- rep
- stosq
- movl %r8d,%ecx
- rep
- stosb
- movq %r9,%rax
- ret
-memset_c_end:
+ .quad memset
+ .quad 1b
+ .byte X86_FEATURE_REP_GOOD
+ .byte .Lfinal - memset
+ .byte 2b - 1b
.previous