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Re: Patch to fix local-alloc REG_EQUIV handling
- To: law at cygnus dot com
- Subject: Re: Patch to fix local-alloc REG_EQUIV handling
- From: John Wehle <john at feith dot com>
- Date: Thu, 8 Mar 2001 21:49:13 -0500 (EST)
- cc: gcc-patches at gcc dot gnu dot org
> validate_equiv_mem verifies that registers in the MEM's address do not die
> across the set of insns where the equivalence might be used by local or
> reload.
I think I'm starting to see the light. If the pseudo isn't explicitly
dead then it must be alive regardless of register allocation / reload.
The problem is that if the pseudo is dead then it may or may not be
alive when the equivalence is used depending on what happened during
register allocation / reload. Hence the HP problem which happened
because the lifetime information of the pseudo used in the LO_SUM was
"wrong".
I know ... it's obvious when you really think about it. Anyway, thanks
for beating through my thick skull. :-)
-- John
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