[llvm-commits] CVS: llvm/lib/VMCore/ConstantFolding.cpp ConstantFolding.h Constants.cpp

[Robert L. Bocchino Jr.]

Changes in directory llvm/lib/VMCore:

ConstantFolding.cpp updated: 1.81 -> 1.82
ConstantFolding.h updated: 1.45 -> 1.46
Constants.cpp updated: 1.143 -> 1.144
---
Log message:

Added constant folding support for the extractelement operation.


---
Diffs of the changes:  (+14 -0)

 ConstantFolding.cpp |   10 ++++++++++
 ConstantFolding.h   |    2 ++
 Constants.cpp       |    2 ++
 3 files changed, 14 insertions(+)


Index: llvm/lib/VMCore/ConstantFolding.cpp
diff -u llvm/lib/VMCore/ConstantFolding.cpp:1.81 llvm/lib/VMCore/ConstantFolding.cpp:1.82
--- llvm/lib/VMCore/ConstantFolding.cpp:1.81	Thu Jan  5 01:49:30 2006
+++ llvm/lib/VMCore/ConstantFolding.cpp	Tue Jan 10 14:03:46 2006
@@ -724,6 +724,16 @@
   return 0;
 }
 
+Constant *llvm::ConstantFoldExtractElementInstruction(const Constant *Val,
+                                                      const Constant *Idx) {
+  if (const ConstantPacked *CVal = dyn_cast<ConstantPacked>(Val)) {
+    if (const ConstantUInt *CIdx = dyn_cast<ConstantUInt>(Idx)) {
+      return const_cast<Constant*>(CVal->getOperand(CIdx->getValue()));
+    }
+  } 
+  return 0;
+}
+
 /// isZeroSizedType - This type is zero sized if its an array or structure of
 /// zero sized types.  The only leaf zero sized type is an empty structure.
 static bool isMaybeZeroSizedType(const Type *Ty) {


Index: llvm/lib/VMCore/ConstantFolding.h
diff -u llvm/lib/VMCore/ConstantFolding.h:1.45 llvm/lib/VMCore/ConstantFolding.h:1.46
--- llvm/lib/VMCore/ConstantFolding.h:1.45	Thu Apr 21 18:46:51 2005
+++ llvm/lib/VMCore/ConstantFolding.h	Tue Jan 10 14:03:46 2006
@@ -31,6 +31,8 @@
   Constant *ConstantFoldSelectInstruction(const Constant *Cond,
                                           const Constant *V1,
                                           const Constant *V2);
+  Constant *ConstantFoldExtractElementInstruction(const Constant *Val,
+                                                  const Constant *Idx);
   Constant *ConstantFoldBinaryInstruction(unsigned Opcode, const Constant *V1,
                                           const Constant *V2);
   Constant *ConstantFoldGetElementPtr(const Constant *C,


Index: llvm/lib/VMCore/Constants.cpp
diff -u llvm/lib/VMCore/Constants.cpp:1.143 llvm/lib/VMCore/Constants.cpp:1.144
--- llvm/lib/VMCore/Constants.cpp:1.143	Tue Jan 10 13:05:24 2006
+++ llvm/lib/VMCore/Constants.cpp	Tue Jan 10 14:03:46 2006
@@ -1403,6 +1403,8 @@
 
 Constant *ConstantExpr::getExtractElementTy(const Type *ReqTy, Constant *Val,
                                             Constant *Idx) {
+  if (Constant *FC = ConstantFoldExtractElementInstruction(Val, Idx))
+    return FC;          // Fold a few common cases...
   // Look up the constant in the table first to ensure uniqueness
   std::vector<Constant*> ArgVec(1, Val);
   ArgVec.push_back(Idx);