cmp %rdi, %r8
jg 2f
- /* FSRM implies ERMS => no length checks, do the copy directly */
+#define CHECK_LEN cmp $0x20, %rdx; jb 1f
+#define MEMMOVE_BYTES movq %rdx, %rcx; rep movsb; RET
.Lmemmove_begin_forward:
- ALTERNATIVE "cmp $0x20, %rdx; jb 1f", "", X86_FEATURE_FSRM
- ALTERNATIVE "", "jmp .Lmemmove_erms", X86_FEATURE_ERMS
+ ALTERNATIVE_2 __stringify(CHECK_LEN), \
+ __stringify(CHECK_LEN; MEMMOVE_BYTES), X86_FEATURE_ERMS, \
+ __stringify(MEMMOVE_BYTES), X86_FEATURE_FSRM
/*
* movsq instruction have many startup latency
movb %r11b, (%rdi)
13:
RET
-
-.Lmemmove_erms:
- movq %rdx, %rcx
- rep movsb
- RET
SYM_FUNC_END(__memmove)
EXPORT_SYMBOL(__memmove)