ref: a277cea8fabeb3ec38484ffc461ae86e5fd8f9b5
dir: /lib/std/memops-impl+posixy-x64.s/
/* std.memblit : (dst : byte#, src : byte#, len : std.size -> void) std.memfill : (dst : byte#, val : byte, len : std.size -> void) */ .globl _std$memblit .globl std$memblit _std$memblit: std$memblit: cmpq %rdi,%rsi movq %rdx,%rcx jz .done jg .fwdcpy movq %rsi,%rax subq %rdi,%rax cmpq %rax,%rcx jg .revcpy .fwdcpy: shrq $3,%rcx rep movsq movq %rdx,%rcx andq $7,%rcx rep movsb jmp .done .revcpy: std leaq -1(%rdx,%rsi),%rsi leaq -1(%rdx,%rdi),%rdi rep movsb cld .done: ret .globl _std$memfill .globl std$memfill _std$memfill: std$memfill: /* generate 8 bytes of fill */ movzbq %sil,%rbx mov $0x101010101010101,%rax imul %rbx,%rax /* and fill */ movq %rdx,%rcx shrq $3,%rcx rep stosq movq %rdx,%rcx andq $7,%rcx rep stosb ret