PostRA Machine LICM does not respect stack adjustments

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Open atrick opened 12 years ago

atrick commented 12 years ago


Bugzilla Link	12009
Version	trunk
OS	All
Attachments	test case IR, .s difference when running LICM after PEI
CC	@asl,@stoklund

LICM should be able to run after PEI. However, it seems to be unaware of some stack adjustments. There's a nice test case from Duncan attached.

1ba3d143-a64b-4671-82b2-0b31cfb91709 commented 12 years ago

I would like to get rid of post-RA LICM completely.

It was only added to clean up after linear scan. It doesn't help a lot after a live range splitting register allocator.

If benchmarks show no regressions, it should simply be disabled.