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MemorySSA: Revert r269678 and r268068; replace with special casing in MemorySSA.
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Authored by pcc on May 25 2016, 6:52 PM.

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Summary

It turns out that too many passes are relying on alias analysis results
for control dependencies. Until we fix that by introducing a more accurate
modelling of control dependencies, special case assume in MemorySSA instead.

Also introduce tests to ensure we don't regress the FunctionAttrs or LICM
passes.

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rL LLVM

Event Timeline

pcc updated this revision to Diff 58553.May 25 2016, 6:52 PM
pcc retitled this revision from to MemorySSA: Revert r269678 and r268068; replace with special casing in MemorySSA..
pcc updated this object.
pcc added a subscriber: llvm-commits.
dberlin edited edge metadata.May 25 2016, 8:22 PM
dberlin added a subscriber: dberlin.

LGTM

(and thanks for taking the time to do this)

This revision was automatically updated to reflect the committed changes.
aaboud added a subscriber: aaboud.May 31 2016, 3:59 AM
aaboud added inline comments.
llvm/trunk/test/Transforms/LICM/assume.ll
17

I am not sure what this test it checking?
Can you explain it ?

Thanks

pcc added inline comments.May 31 2016, 4:53 PM
llvm/trunk/test/Transforms/LICM/assume.ll
17

This test is checking that the licm pass does not remove calls to llvm.assume when hoisting code out of a loop. This was one of the regressions caused by r268068.