Re: What is faster Ada or C?

[Pascal Obry <p.obry@wanadoo.fr>]

Georg Bauhaus <sb463ba@l1-hrz.uni-duisburg.de> writes:

> 
> Here is side by side output:
> 
>         .file   "silly.adb"             .file   "silly.c"
> gcc2_compiled.:                    gcc2_compiled.:
> ___gnu_compiled_ada:               ___gnu_compiled_c:
> .text                              .text
>         .align 4                        .align 4
> .globl __ada_silly                 .globl _silly
> __ada_silly:                       _silly:
>         pushl %ebp                      pushl %ebp
>         movl %esp,%ebp                  movl %esp,%ebp
>         subl $8,%esp                    subl $8,%esp
>         movl $0,-4(%ebp)                movl $0,-4(%ebp)
>         movl $1,-8(%ebp)                movl $1,-8(%ebp)
> L2:                                L2:
>         cmpl $1000,-8(%ebp)             cmpl $1000,-8(%ebp)
>         jle L5                          jle L5
>         jmp L3                          jmp L3
>         .align 2,0x90                   .align 2,0x90
> L5:                                L5:
>         incl -4(%ebp)                   incl -4(%ebp)
>         jmp L4                     L4:
>         .align 2,0x90                   incl -8(%ebp)
>         jmp L3                          jmp L2
>         .align 2,0x90                   .align 2,0x90
> L6:                                L3:
> L4:                                     movl -4(%ebp),%edx
>         incl -8(%ebp)                   movl %edx,%eax
>         jmp L2                          jmp L1
>         .align 2,0x90                   .align 2,0x90
> L3:                                L1:
>         movl -4(%ebp),%edx              movl %ebp,%esp
>         movl %edx,%eax                  popl %ebp
>         jmp L1                          ret
>         .align 2,0x90
> L1:
>         movl %ebp,%esp
>         popl %ebp
>         ret
> 

Here is the GNAT 5 output: "-S -gnatp"

	.file	"silly.adb"
	.text
	.align 2
.globl __ada_silly
	.def	__ada_silly;	.scl	2;	.type	32;	.endef
__ada_silly:
	pushl	%ebp
	movl	%esp, %ebp
	subl	$8, %esp
	movl	$0, -4(%ebp)
	movl	$1, -8(%ebp)
L2:
	cmpl	$1000, -8(%ebp)
	jle	L5
	jmp	L3
L5:
	leal	-4(%ebp), %eax
	incl	(%eax)
	leal	-8(%ebp), %eax
	incl	(%eax)
	jmp	L2
L3:
	movl	-4(%ebp), %eax
	leave
	ret

And with "-S -gnatp -O2"

	.file	"silly.adb"
	.text
	.align 2
	.p2align 4,,15
.globl __ada_silly
	.def	__ada_silly;	.scl	2;	.type	32;	.endef
__ada_silly:
	pushl	%ebp
	movl	$999, %eax
	movl	%esp, %ebp
	.p2align 4,,7
L8:
	decl	%eax
	jns	L8
	movl	$1000, %eax
	popl	%ebp
	ret

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|         http://perso.wanadoo.fr/pascal.obry
--|
--| "The best way to travel is by means of imagination"