one simple question
Cordula's Web
cpghost at cordula.ws
Thu Mar 4 00:16:48 PST 2004
> I compile a test C file. I notice there are a few lines at the
> beginning of the assembly code. I want to know what it means, but
> can't figure out one of them. Can anyone tell me what the
> following line does please?
>
> and $0xfffffff0,%esp
Hmmm, when I compile the simplest possible C file:
-------------------------------
int
main (int argc, char *argv[])
{
return 0;
}
--------------------------------
I get this:
--------------------------------
.file "test1.c"
.version "01.01"
gcc2_compiled.:
.text
.p2align 2,0x90
.globl main
.type main, at function
main:
pushl %ebp
movl %esp,%ebp
xorl %eax,%eax
jmp .L2
.p2align 2,0x90
.L2:
leave
ret
.Lfe1:
.size main,.Lfe1-main
.ident "GCC: (GNU) c 2.95.4 20020320 [FreeBSD]"
--------------------------------
No such thing as:
and $0xfffffff0,%esp
Are you using gcc 3.3.x?
Anyway, this code looks like it would align the stack
the stack pointer...
> best regards
> Chungwei
--
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