Re: [tree-ssa] Remove LOOP_EXPR

[Jason Merrill <jason at redhat dot com>]

On Wed, 03 Sep 2003 09:49:44 -0400, Diego Novillo <dnovillo@redhat.com> wrote:

> On Wed, 2003-09-03 at 00:48, law@redhat.com wrote:
>
>> As for how to fix this.  It seems to me that if the FE is creating a
>> LOOP_EXPR, then lowering the LOOP_EXPR to gimple is really language
>> independent.  Right?  In fact, given a generic LOOP_EXPR, shouldn't
>> all we have to do to lower that is create the LABEL_EXPR and GOTO_EXPR
>> to make the looping explicit in the IL?
>> 
> This gives us one more reason for having separate lowering passes.  At
> the time, I was mostly motivated by QOI issues, but now I think we have
> a very good reason to have this lowering done in a truly
> language-independent pass, together with COND_EXPR and EH lowering.

I don't follow.  The problem here is that the lowering was happening in C
frontend code, rather than in the language-independent gimplifier.  I don't
have a particular preference for doing the lowering in the gimplifier, but
I don't see this as an argument against it.

Jason