aligned v.s. unaligned (?
.file "aligned-vs-unaligned.c"
.section .rodata
.LC0:
.string "aligned (%p) = %d\n"
.LC1:
.string "unaligned (%p) = %d\n"
.text
.globl main
.type main, @function
main:
.LFB0:
.cfi_startproc
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset 6, -16
movq %rsp, %rbp
.cfi_def_cfa_register 6
addq $-128, %rsp
movq %fs:40, %rax
movq %rax, -8(%rbp)
xorl %eax, %eax
leaq -112(%rbp), %rdx
movl $0, %eax
movl $12, %ecx
movq %rdx, %rdi
rep stosq
movq %rdi, %rdx
movl %eax, (%rdx)
addq $4, %rdx
movb $1, -112(%rbp)
movb $2, -111(%rbp)
movb $3, -110(%rbp)
movb $4, -109(%rbp)
movb $5, -108(%rbp)
leaq -112(%rbp), %rax
movq %rax, -120(%rbp)
movq -120(%rbp), %rax
movl (%rax), %edx
movq -120(%rbp), %rax
movq %rax, %rsi
leaq .LC0(%rip), %rdi
movl $0, %eax
call printf@PLT
leaq -112(%rbp), %rax
addq $1, %rax
movq %rax, -120(%rbp)
movq -120(%rbp), %rax
movl (%rax), %edx
movq -120(%rbp), %rax
movq %rax, %rsi
leaq .LC1(%rip), %rdi
movl $0, %eax
call printf@PLT
movl $0, %eax
movq -8(%rbp), %rcx
xorq %fs:40, %rcx
je .L3
call __stack_chk_fail@PLT
.L3:
leave
.cfi_def_cfa 7, 8
ret
.cfi_endproc
.LFE0:
.size main, .-main
.ident "GCC: (Ubuntu 6.2.0-5ubuntu12) 6.2.0 20161005"
.section .note.GNU-stack,"",@progbits
#include<stdio.h>
int main() {
char c[100] = { 1, 2, 3, 4, 5 };
int* p = (int*) c;
printf("aligned (%p) = %d\n", p, *p);
p = (int*) (c + 1);
printf("unaligned (%p) = %d\n", p, *p);
}