stack-params.c

stack-params.c

// https://godbolt.org/g/2xOK3B

int foo(int x) {
  int y = 20;
  return x + y;
}

int main() {
  foo(10);
  return 0;
}

/* asm

foo(int):                                # @foo(int)
        pushq   %rbp
        movq    %rsp, %rbp
        movl    %edi, -4(%rbp)
        movl    $20, -8(%rbp)
        movl    -4(%rbp), %edi
        addl    -8(%rbp), %edi
        movl    %edi, %eax
        popq    %rbp
        retq

main:                                   # @main
        pushq   %rbp
        movq    %rsp, %rbp
        subq    $16, %rsp
        movl    $10, %edi
        movl    $0, -4(%rbp)
        callq   foo(int)
        xorl    %edi, %edi
        movl    %eax, -8(%rbp)          # 4-byte Spill
        movl    %edi, %eax
        addq    $16, %rsp
        popq    %rbp
        retq

*/