diff options
| author | Andy Kaylor <andrew.kaylor@intel.com> | 2020-01-23 16:37:24 -0800 |
|---|---|---|
| committer | Andy Kaylor <andrew.kaylor@intel.com> | 2020-01-23 18:18:50 -0800 |
| commit | c467faf23c7abda60cfd5486a39ffadd6f546d5c (patch) | |
| tree | 52bf653f68a9db10a4e1d079403e6c011ce57371 /llvm/lib/Transforms/Utils/SimplifyCFG.cpp | |
| parent | 580d7838dd08e13dac6caf4ab3142c9381bc7ad0 (diff) | |
| download | llvm-c467faf23c7abda60cfd5486a39ffadd6f546d5c.zip llvm-c467faf23c7abda60cfd5486a39ffadd6f546d5c.tar.gz llvm-c467faf23c7abda60cfd5486a39ffadd6f546d5c.tar.bz2 | |
[WinEH] Ignore lifetime.end PHI nodes in empty cleanuppads
This fixes a bug where a PHI node that is only referenced by a lifetime.end intrinsic in an otherwise empty cleanuppad can cause SimplyCFG to create an SSA violation while removing the empty cleanuppad. Theoretically the same problem can occur with debug intrinsics.
Differential Revision: https://reviews.llvm.org/D72540
Diffstat (limited to 'llvm/lib/Transforms/Utils/SimplifyCFG.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Utils/SimplifyCFG.cpp | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index d93ca4f..222f8af 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -4083,9 +4083,10 @@ static bool removeEmptyCleanup(CleanupReturnInst *RI) { // The iterator must be incremented here because the instructions are // being moved to another block. PHINode *PN = cast<PHINode>(I++); - if (PN->use_empty()) - // If the PHI node has no uses, just leave it. It will be erased - // when we erase BB below. + if (PN->use_empty() || !PN->isUsedOutsideOfBlock(BB)) + // If the PHI node has no uses or all of its uses are in this basic + // block (meaning they are debug or lifetime intrinsics), just leave + // it. It will be erased when we erase BB below. continue; // Otherwise, sink this PHI node into UnwindDest. |