Schedule ThinLTOBuffer passes again after sanitizer passes

This works around a design defect in the LLVM 12 pass builder
implementation. In LLVM 13, the PreLink ThinLTO pipeline properly
respects the OptimizerLastEPCallbacks.
This commit is contained in:
Nikita Popov 2021-03-02 21:54:03 +01:00
parent ea0aa8def3
commit 9a8acea783
1 changed files with 6 additions and 1 deletions

View File

@ -1015,7 +1015,12 @@ LLVMRustOptimizeWithNewPassManager(
case LLVMRustOptStage::PreLinkThinLTO:
#if LLVM_VERSION_GE(12, 0)
MPM = PB.buildThinLTOPreLinkDefaultPipeline(OptLevel);
NeedThinLTOBufferPasses = false;
// The ThinLTOPreLink pipeline already includes ThinLTOBuffer passes. However, callback
// passes may still run afterwards. This means we need to run the buffer passes again.
// FIXME: In LLVM 13, the ThinLTOPreLink pipeline also runs OptimizerLastEPCallbacks
// before the RequiredLTOPreLinkPasses, in which case we can remove these hacks.
if (OptimizerLastEPCallbacks.empty())
NeedThinLTOBufferPasses = false;
#else
MPM = PB.buildThinLTOPreLinkDefaultPipeline(OptLevel, DebugPassManager);
#endif