A C Compiler implementation as shown in (https://github.com/DoctorWkt/acwj)
make command :
make tinyC
-v give verbose output of the compilation stages
-c generate object files but don't link them
-S generate assembly files but don't link them
-T dump the AST trees for each input file
-M dump the symbol table for each input file
-o outfile, produce the outfile executable file
Simple C program :
//file.c
#include<stdio.h>
void main()
{
int a;
a = 10;
a += 10;
printf("%d\n",a);
}To execute above code :
tinyC file.c
Output :
: ./a.out
20
Now let's execute using option :
tinyC -S file.c
Generated assembly file using -S option which is file.s below :
//file.s
# freeing all registers
.text
# internal switch(expr) routine
# %rsi = switch table, %rax = expr
# from SubC: http://www.t3x.org/subc/
__switch:
pushq %rsi
movq %rdx, %rsi
movq %rax, %rbx
cld
lodsq
movq %rax, %rcx
__next:
lodsq
movq %rax, %rdx
lodsq
cmpq %rdx, %rbx
jnz __no
popq %rsi
jmp *%rax
__no:
loop __next
lodsq
popq %rsi
jmp *%rax
L18:
.byte 37
.byte 100
.byte 10
.byte 0
.globl main
.type main, @function
main:
pushq %rbp
movq %rsp, %rbp
addq $-16,%rsp
# allocated register %r10
movq $10, %r10
movl %r10d, -4(%rbp)
# freeing all registers
# allocated register %r10
movslq -4(%rbp), %r10
# allocated register %r11
movq $10, %r11
addq %r11, %r10
# freeing reg %r11
movl %r10d, -4(%rbp)
# freeing all registers
# freeing all registers
pushq %r10
pushq %r11
pushq %r12
pushq %r13
# allocated register %r10
movslq -4(%rbp), %r10
movq %r10, %rsi
# freeing reg %r10
# allocated register %r10
leaq L18(%rip), %r10
movq %r10, %rdi
# freeing reg %r10
call printf@PLT
popq %r13
popq %r12
popq %r11
popq %r10
# allocated register %r10
movq %rax, %r10
# freeing all registers
L17:
addq $16,%rsp
popq %rbp
ret
# freeing all registers