- push rsi\r
- push rdi\r
- mov rsi, rdx # rsi <- Source\r
- mov rdi, rcx # rdi <- Destination\r
- lea r9, [rsi + r8 - 1] # r9 <- End of Source\r
- cmp rsi, rdi\r
- mov rax, rdi # rax <- Destination as return value\r
+ pushq %rsi\r
+ pushq %rdi\r
+ movq %rdx, %rsi # rsi <- Source\r
+ movq %rcx, %rdi # rdi <- Destination\r
+ leaq -1(%rsi, %r8,), %r9 # r9 <- End of Source\r
+ cmpq %rdi, %rsi\r
+ movq %rdi, %rax # rax <- Destination as return value\r