diff options
Diffstat (limited to 'arch/x86/lib/memmove_64.S')
| -rw-r--r-- | arch/x86/lib/memmove_64.S | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S index 337830d7a59c..7ff00ea64e4f 100644 --- a/arch/x86/lib/memmove_64.S +++ b/arch/x86/lib/memmove_64.S @@ -29,10 +29,7 @@ SYM_FUNC_START_ALIAS(memmove) SYM_FUNC_START(__memmove) - /* Handle more 32 bytes in loop */ mov %rdi, %rax - cmp $0x20, %rdx - jb 1f /* Decide forward/backward copy mode */ cmp %rdi, %rsi @@ -42,7 +39,9 @@ SYM_FUNC_START(__memmove) cmp %rdi, %r8 jg 2f + /* FSRM implies ERMS => no length checks, do the copy directly */ .Lmemmove_begin_forward: + ALTERNATIVE "cmp $0x20, %rdx; jb 1f", "", X86_FEATURE_FSRM ALTERNATIVE "", "movq %rdx, %rcx; rep movsb; retq", X86_FEATURE_ERMS /* @@ -114,6 +113,8 @@ SYM_FUNC_START(__memmove) */ .p2align 4 2: + cmp $0x20, %rdx + jb 1f cmp $680, %rdx jb 6f cmp %dil, %sil |