分析RISC-V汇编代码
#include <stdio.h>
int g(int x){
return x+3;
}
int f(int x){
return g(x);
}
int main(){
return f(8)+1;
}
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编译后:
.file "add.c"
.option nopic
.attribute arch, "rv64i2p0_m2p0_a2p0_f2p0_d2p0_c2p0"
.attribute unaligned_access, 0
.attribute stack_align, 16
.text
.align 1
.globl g
.type g, @function
g:
addi sp,sp,-32
sd s0,24(sp)
addi s0,sp,32
mv a5,a0
sw a5,-20(s0)
lw a5,-20(s0)
addiw a5,a5,3
sext.w a5,a5
mv a0,a5
ld s0,24(sp)
addi sp,sp,32
jr ra
.size g, .-g
.align 1
.globl f
.type f, @function
f:
addi sp,sp,-32
sd ra,24(sp)
sd s0,16(sp)
addi s0,sp,32
mv a5,a0
sw a5,-20(s0)
lw a5,-20(s0)
mv a0,a5
call g
mv a5,a0
mv a0,a5
ld ra,24(sp)
ld s0,16(sp)
addi sp,sp,32
jr ra
.size f, .-f
.align 1
.globl main
.type main, @function
main:
addi sp,sp,-16
sd ra,8(sp)
sd s0,0(sp)
addi s0,sp,16
li a0,8
call f
mv a5,a0
addiw a5,a5,1
sext.w a5,a5
mv a0,a5
ld ra,8(sp)
ld s0,0(sp)
addi sp,sp,16
jr ra
.size main, .-main
.ident "GCC: (SiFive GCC 8.3.0-2020.04.0) 8.3.0"
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Last updated: 2022/12/04, 13:58:10