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| author | Evan Cheng <evan.cheng@apple.com> | 2012-07-27 21:21:26 +0000 |
|---|---|---|
| committer | Evan Cheng <evan.cheng@apple.com> | 2012-07-27 21:21:26 +0000 |
| commit | 9c777a484415198b3fb0dbeb57a594573b245152 (patch) | |
| tree | 4ea25afd74753d508392459dea518509f0b8d897 /lib/Transforms/Scalar | |
| parent | b18d779b35909cd5b753871f8bf2ff4f6c17ace1 (diff) | |
| download | external_llvm-9c777a484415198b3fb0dbeb57a594573b245152.zip external_llvm-9c777a484415198b3fb0dbeb57a594573b245152.tar.gz external_llvm-9c777a484415198b3fb0dbeb57a594573b245152.tar.bz2 | |
Teach CodeGenPrep to look past bitcast when it's duplicating return instruction
into predecessor blocks to enable tail call optimization.
rdar://11958338
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160894 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Transforms/Scalar')
| -rw-r--r-- | lib/Transforms/Scalar/CodeGenPrepare.cpp | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp index f425cd0..4b4a8c5 100644 --- a/lib/Transforms/Scalar/CodeGenPrepare.cpp +++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp @@ -645,10 +645,18 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) { if (!TLI) return false; + PHINode *PN = 0; + BitCastInst *BCI = 0; Value *V = RI->getReturnValue(); - PHINode *PN = V ? dyn_cast<PHINode>(V) : NULL; - if (V && !PN) - return false; + if (V) { + BCI = dyn_cast<BitCastInst>(V); + if (BCI) + V = BCI->getOperand(0); + + PN = dyn_cast<PHINode>(V); + if (!PN) + return false; + } BasicBlock *BB = RI->getParent(); if (PN && PN->getParent() != BB) @@ -666,6 +674,9 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) { if (PN) { BasicBlock::iterator BI = BB->begin(); do { ++BI; } while (isa<DbgInfoIntrinsic>(BI)); + if (&*BI == BCI) + // Also skip over the bitcast. + ++BI; if (&*BI != RI) return false; } else { |