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[GVN] Don't perform scalar PRE on GEPs

Description

[GVN] Don't perform scalar PRE on GEPs

Partial Redundancy Elimination of GEPs prevents CodeGenPrepare from
sinking the addressing mode computation of memory instructions back
to its uses. The problem comes from the insertion of PHIs, which
confuse CGP and make it bail.

I've autogenerated the check lines of an existing test and added a
store instruction to demonstrate the motivation behind this change.
The store is now using the gep instead of a phi.

Differential Revision: https://reviews.llvm.org/D55009

Details

Committed
alelab01Dec 6 2018, 8:11 AM
Differential Revision
D55009: [GVN] Don't perform scalar PRE on GEPs
Parents
rL348495: [DEBUGINFO, NVPTX]Emit last debugging directives.
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