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| author | Philip Reames <listmail@philipreames.com> | 2015-08-26 23:56:46 +0000 |
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| committer | Philip Reames <listmail@philipreames.com> | 2015-08-26 23:56:46 +0000 |
| commit | 98a2dabc08fd89375f3af4158eb55575be58f13c (patch) | |
| tree | fd49a855569c92ec67de35a095dd28fe9f9f143d /llvm/lib/Transforms/Utils/LoopUtils.cpp | |
| parent | a06c7e6da7f7367103d5522617cceb2525f2b431 (diff) | |
| download | llvm-98a2dabc08fd89375f3af4158eb55575be58f13c.zip llvm-98a2dabc08fd89375f3af4158eb55575be58f13c.tar.gz llvm-98a2dabc08fd89375f3af4158eb55575be58f13c.tar.bz2 | |
[SimplifyCFG] Prune code from a provably unreachable switch default
As Sanjoy pointed out over in http://reviews.llvm.org/D11819, a switch on an icmp should always be able to become a branch instruction. This patch generalizes that notion slightly to prove that the default case of a switch is unreachable if the cases completely cover all possible bit patterns in the condition. Once that's done, the switch to branch conversion kicks in just fine.
Note: Duplicate case values are disallowed by the LangRef and verifier.
Differential Revision: http://reviews.llvm.org/D11995
llvm-svn: 246125
Diffstat (limited to 'llvm/lib/Transforms/Utils/LoopUtils.cpp')
0 files changed, 0 insertions, 0 deletions