diff options
| author | Andi Kleen <ak@suse.de> | 2005-11-05 17:25:54 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-11-14 19:55:17 -0800 |
| commit | a5b250a428aabc619ace872f8220a7d0b8f7d557 (patch) | |
| tree | 11cabf07982ae37f94bc929f9a605cbbd20e35ab /arch/x86_64/lib/memset.S | |
| parent | a6f5deb2be4c82f24fefadcbf7e448f540c05ae6 (diff) | |
[PATCH] x86_64: Remove optimization for B stepping AMD K8
B stepping were the first shipping Opterons. memcpy/memset/copy_page/
clear_page had special optimized version for them. These are really
old and in the minority now and the difference to the generic versions
(using rep microcode) is not that big anyways. So just remove them.
TODO: figure out optimized versions for Intel Netburst based EM64T
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/x86_64/lib/memset.S')
| -rw-r--r-- | arch/x86_64/lib/memset.S | 94 |
1 files changed, 0 insertions, 94 deletions
diff --git a/arch/x86_64/lib/memset.S b/arch/x86_64/lib/memset.S index 4b4c4063864..2aa48f24ed1 100644 --- a/arch/x86_64/lib/memset.S +++ b/arch/x86_64/lib/memset.S @@ -13,98 +13,6 @@ .p2align 4 memset: __memset: - movq %rdi,%r10 - movq %rdx,%r11 - - /* expand byte value */ - movzbl %sil,%ecx - movabs $0x0101010101010101,%rax - mul %rcx /* with rax, clobbers rdx */ - - /* align dst */ - movl %edi,%r9d - andl $7,%r9d - jnz .Lbad_alignment -.Lafter_bad_alignment: - - movl %r11d,%ecx - shrl $6,%ecx - jz .Lhandle_tail - - .p2align 4 -.Lloop_64: - decl %ecx - movq %rax,(%rdi) - movq %rax,8(%rdi) - movq %rax,16(%rdi) - movq %rax,24(%rdi) - movq %rax,32(%rdi) - movq %rax,40(%rdi) - movq %rax,48(%rdi) - movq %rax,56(%rdi) - leaq 64(%rdi),%rdi - jnz .Lloop_64 - - /* Handle tail in loops. The loops should be faster than hard - to predict jump tables. */ - .p2align 4 -.Lhandle_tail: - movl %r11d,%ecx - andl $63&(~7),%ecx - jz .Lhandle_7 - shrl $3,%ecx - .p2align 4 -.Lloop_8: - decl %ecx - movq %rax,(%rdi) - leaq 8(%rdi),%rdi - jnz .Lloop_8 - -.Lhandle_7: - movl %r11d,%ecx - andl $7,%ecx - jz .Lende - .p2align 4 -.Lloop_1: - decl %ecx - movb %al,(%rdi) - leaq 1(%rdi),%rdi - jnz .Lloop_1 - -.Lende: - movq %r10,%rax - ret - -.Lbad_alignment: - cmpq $7,%r11 - jbe .Lhandle_7 - movq %rax,(%rdi) /* unaligned store */ - movq $8,%r8 - subq %r9,%r8 - addq %r8,%rdi - subq %r8,%r11 - jmp .Lafter_bad_alignment - - /* C stepping K8 run faster using the string instructions. - It is also a lot simpler. Use this when possible */ - -#include <asm/cpufeature.h> - - .section .altinstructions,"a" - .align 8 - .quad memset - .quad memset_c - .byte X86_FEATURE_K8_C - .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 @@ -121,5 +29,3 @@ memset_c: stosb movq %r9,%rax ret -memset_c_end: - .previous |