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BreakCriticalEdges for callbr indirect dests

Authored by nickdesaulniers on Jun 17 2020, 11:37 AM.

Description

BreakCriticalEdges for callbr indirect dests

Summary:
llvm::SplitEdge was failing an assertion that the BasicBlock only had
one successor (for BasicBlocks terminated by CallBrInst, we typically
have multiple successors). It was surprising that the earlier call to
SplitCriticalEdge did not handle the critical edge (there was an early
return). Removing that triggered another assertion relating to creating
a BlockAddress for a BasicBlock that did not (yet) have a parent, which
is a simple order of operations issue in llvm::SplitCriticalEdge (a
freshly constructed BasicBlock must be inserted into a Function's basic
block list to have a parent).

Thanks to @nathanchance for the report.
Fixes: https://github.com/ClangBuiltLinux/linux/issues/1018

Reviewers: craig.topper, jyknight, void, fhahn, efriedma

Reviewed By: efriedma

Subscribers: eli.friedman, rnk, efriedma, fhahn, hiraditya, llvm-commits, nathanchance, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81607

Details

Committed
nickdesaulniersJun 17 2020, 11:45 AM
Reviewer
efriedma
Differential Revision
D81607: BreakCriticalEdges for callbr indirect dests
Parents
rG9b22b29f684f: [mlir] [VectorOps] Add create mask integration tests
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