[PATCH] Restrict jump threading statement simplifier to scalar types (PR71077)

Jeff Law law@redhat.com
Thu Aug 18 19:59:00 GMT 2016


On 08/18/2016 01:22 PM, Richard Biener wrote:
> On August 18, 2016 8:25:18 PM GMT+02:00, Patrick Palka <patrick@parcs.ath.cx> wrote:
>> In comment #5 Yuri reports that r235653 introduces a runtime failure
>> for
>> 176.gcc which I guess is caused by the combining step in
>> simplify_control_stmt_condition_1() not behaving properly on operands
>> of
>> type VECTOR_TYPE.  I'm a bit stumped as to why it mishandles
>> VECTOR_TYPEs because the logic should be generic enough to support them
>> as well.  But it was confirmed that restricting the combining step to
>> operands of scalar type fixes the runtime failure so here is a patch
>> that does this.  Does this look OK to commit after bootstrap +
>> regtesting on x86_64-pc-linux-gnu?
>
> Hum, I'd rather understand what is going wrong.  Can you at least isolate a testcase?
Agreed.  And a fix like this ought to include that isolated test in the 
regression suite.

jeff



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