diff options
| author | Nadav Rotem <nadav.rotem@intel.com> | 2011-08-28 11:51:08 +0000 |
|---|---|---|
| committer | Nadav Rotem <nadav.rotem@intel.com> | 2011-08-28 11:51:08 +0000 |
| commit | be6ceb6ebcfb48e09ffab297c1537c87383f0ce9 (patch) | |
| tree | e05e876a1b8886b72f3abe66192ec5fdcbfe0cfa /lib/Analysis/ConstantFolding.cpp | |
| parent | b1b051ec97c4e3c02cea554e169cbb4f85bcb2de (diff) | |
Bitcasts are transitive. Bitcast-Bitcast-X becomes Bitcast-X.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138722 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Analysis/ConstantFolding.cpp')
| -rw-r--r-- | lib/Analysis/ConstantFolding.cpp | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp index df79849c3c..613804d6d2 100644 --- a/lib/Analysis/ConstantFolding.cpp +++ b/lib/Analysis/ConstantFolding.cpp @@ -51,6 +51,12 @@ static Constant *FoldBitCast(Constant *C, Type *DestTy, if (C->isAllOnesValue() && !DestTy->isX86_MMXTy()) return Constant::getAllOnesValue(DestTy); + // Bitcast of Bitcast can be done using a single cast. + ConstantExpr *CE = dyn_cast<ConstantExpr>(C); + if (CE && CE->getOpcode() == Instruction::BitCast) { + return ConstantExpr::getBitCast(CE->getOperand(0), DestTy); + } + // The code below only handles casts to vectors currently. VectorType *DestVTy = dyn_cast<VectorType>(DestTy); if (DestVTy == 0) |