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1a3fdaf6a6
Summary: When inserting uses from outside the MemorySSA creation, we don't normally need to rename uses, based on the assumption that there will be no inserted Phis (if Def existed that required a Phi, that Phi already exists). However, when dealing with unreachable blocks, MemorySSA will optimize away Phis whose incoming blocks are unreachable, and these Phis end up being re-added when inserting a Use. There are two potential solutions here: 1. Analyze the inserted Phis and clean them up if they are unneeded (current method for cleaning up trivial phis does not cover this) 2. Leave the Phi in place and rename uses, the same way as whe inserting defs. This patch use approach 2. Resolves first test in PR42940. Reviewers: george.burgess.iv Subscribers: Prazek, sanjoy.google, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D66033 llvm-svn: 369291
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This directory and its subdirectories contain source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments.