Function without prologue and epilogue

Question

Function without prologue and epilogue

How can I set a function without a prologue and an epilogue so that only the body code is created?

For example, to have the function

void func() {
    __asm__ volatile__ ("nop");
}

Compiled into the code

0:  90                      nop

Instead of the code

0:  55                      push   %ebp
1:  89 e5                   mov    %esp,%ebp
3:  90                      nop
4:  5d                      pop    %ebp
5:  c3                      ret

Are there standard C tools (visual c, gcc) ?

6

c ассемблер

Author: Alex, 2010-11-24

Source

1 answers

score 10 · Accepted Answer

There is no such feature in the C standard. It can be provided by specific compilers. For example, for Visual C++ on the x86 platform, it will look like this:

__declspec( naked ) void func( void ) { __asm { nop } }

For ARM gcc:

void func() __attribute__ ((naked));

void func(void) {
    __asm__ __volatile__("nop");
}