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@upsuper
Created August 22, 2012 09:23
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"xor rax, rax" vs. "mov rax, 0"
Environment: Mac OS X 10.7.4
Compiler: yasm 1.2.0
all: mov xor
mov: mov.o
ld -o mov mov.o
xor: xor.o
ld -o xor xor.o
mov.o: mov.asm
yasm -f macho64 -o mov.o mov.asm
xor.o: xor.asm
yasm -f macho64 -o xor.o xor.asm
global start
start:
mov rcx, 1048576
loop0:
times 1024 mov rax, 0
dec rcx
jnz loop0
mov rax, 0x2000001
mov rdi, 0
syscall
global start
start:
mov rcx, 1048576
loop0:
times 1024 xor rax, rax
dec rcx
jnz loop0
mov rax, 0x2000001
mov rdi, 0
syscall
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