From: Weiming Zhao <weimingz@codeaurora.org>
Date: Thu, 19 Nov 2015 02:45:18 +0000 (+0000)
Subject: Fix bug 25440: GVN assertion after coercing loads
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=commitdiff_plain;h=f9d8b8d2ab35abd0dc879099cba8260833a04dc0;hp=f9d8b8d2ab35abd0dc879099cba8260833a04dc0

Fix bug 25440: GVN assertion after coercing loads

Optimizations like LoadPRE in GVN will insert new instructions.
If the insertion point is in a already processed BB, they should
get a value number explicitly. If the insertion point is after
current instruction, then just leave it. However, current GVN framework
has no support for it.
In this patch, we just bail out if a VN can't be found.

Dfferential Revision: http://reviews.llvm.org/D14670

A    test/Transforms/GVN/pr25440.ll
M    lib/Transforms/Scalar/GVN.cpp


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253536 91177308-0d34-0410-b5e6-96231b3b80d8
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