Re: Structure vs purism ?

Arvind Sankar (arvinds@mit.edu)
Fri, 22 Jan 1999 12:29:07 -0500

On Fri, Jan 22, 1999 at 08:44:31AM -0500, Richard B. Johnson wrote:
> > .p2align 4,,7
> > .L5:
> > pushl $.LC0 # this was the string
> > call puts # even inlines foo() for you :-)
> > addl $4,%esp
> > subl $1,%ebx # mm.. ah! decl doesn't affect the flags
> Err... decl doesn't affect the carry flag. It affects
> OF, SF, ZF, AF, and PF.
> They could `jns` for numbers less than MAX_INT.

eep! and here I thought compilers were getting a little more intelligent.
They could inc the start value and use jne for all numbers... but is
subl slower than decl? It's certainly bigger...

>
>
> > jnc .L5
> > movl -4(%ebp),%ebx
> > movl %ebp,%esp
> > popl %ebp
> > ret
>

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