Re: [PATCH] See through ADDR_EXPR for forwprop

[Richard Guenther <rguenth at tat dot physik dot uni-tuebingen dot de>]

Jeffrey A Law wrote:
> On Mon, 2005-05-23 at 14:10 +0200, Richard Guenther wrote:
> 
>>This patch enables us to forward-propagate ADDR_EXPRs of the form
>>
>>alias2.cpp.t21.dce1:
>>  D.2326_109 = &dX.D.2303.D.2259.domain_m[0].D.2216;
>>  D.2326_110 = D.2326_109;
>>  D.2327_111 = &D.2326_110->D.2207;
>>  this_112 = D.2327_111;
>>  D.2802_113 = this_112->D.2161.domain_m;
>>
>>alias2.cpp.t22.forwprop1
>>  D.2802_113 = dX.D.2303.D.2259.domain_m[0].D.2216.D.2207.D.2161.domain_m;
>>
>>in one step, instead of waiting for .t75.forwprop3 like
>>happened in the testcase for PR19626.
>>
>>Any reason why we should not do this?
>>
>>Bootstrapped on x86_64-unknown-linux-gnu, regtesting in progress.
>>
>>Ok for mainline after slush?
>>
>>Thanks,
>>Richard.
>>plain text document attachment (fix-forwprop)
>>2005-05-23  Richard Guenther  <rguenth@gcc.gnu.org>
>>
>>	* tree-ssa-forwprop.c (forward_propagate_addr_expr):
>>	See through ADDR_EXPR in finding place to propagate into.
> 
> I'm pretty sure you can't have an ADDR_EXPR on the LHS, so I suspect
> checking for it is just a tiny waste of time.  I'm going to rebootstrap
> and retest with the first hunk removed.

Ok, I only had this for completeness.  I'll need to learn more of what
exactly is gimple and what not.

Thanks,
Richard.