x86-64's assembler source

5 Sep 2005

      Hallo, suse-amd64 ML!

I have a question about assembler source(gas) on x86-64.
It is a thing about a .s file's difference between x86 and x86-64.

For example, as the following C source
$ cat foo.c
int main()
{
        return 0;
}

When assemble it in 32bit(-m32)

        .file   "foo.c"
        .text
.globl main
        .type   main, @function
main:
        pushl   %ebp
        movl    %esp, %ebp
        subl    $8, %esp
        andl    $-16, %esp
        movl    $0, %eax
        addl    $15, %eax
        addl    $15, %eax
        shrl    $4, %eax
        sall    $4, %eax
        subl    %eax, %esp
        movl    $0, %eax
        leave
        ret
        .size   main, .-main
        .section        .note.GNU-stack,"",@progbits
        .ident  "GCC: (GNU) 3.3.4 (pre 3.3.5 20040809)"

And the following source is a asm source in 64bit.

        .file   "foo.c"
        .text
.globl main
        .type   main, @function
main:
.LFB3:
        pushq   %rbp
.LCFI0:
        movq    %rsp, %rbp
.LCFI1:
        movl    $0, %eax
        leave
        ret
.LFE3:
        .size   main, .-main
        .section        .eh_frame,"a",@progbits
.Lframe1:
        .long   .LECIE1-.LSCIE1
.LSCIE1:
        .long   0x0
        .byte   0x1
        .string ""
        .uleb128 0x1
        .sleb128 -8
        .byte   0x10
        .byte   0xc
        .uleb128 0x7
        .uleb128 0x8
        .byte   0x90
        .uleb128 0x1
        .align 8
.LECIE1:
.LSFDE1:
        .long   .LEFDE1-.LASFDE1
.LASFDE1:
        .long   .LASFDE1-.Lframe1
        .quad   .LFB3
        .quad   .LFE3-.LFB3
        .byte   0x4
        .long   .LCFI0-.LFB3
        .byte   0xe
        .uleb128 0x10
        .byte   0x86
        .uleb128 0x2
        .byte   0x4
        .long   .LCFI1-.LCFI0
        .byte   0xd
        .uleb128 0x6
        .align 8
.LEFDE1:
        .section        .note.GNU-stack,"",@progbits
        .ident  "GCC: (GNU) 3.3.4 (pre 3.3.5 20040809)"

A lot of label is added in 64bit mode.
(.LFB3, .LCFI0, .LCFI1, .LFE3, .Lframe1, .LSCIE1, .LECIE1,
.LSFDE1, .LASFDE1, .LEFDE1)

Is there a person knowing what kind of meanings these are?
Or is there a person knowing some site or book to be useful for?

best regards
eshsf