[llvm-commits] CVS: llvm/lib/VMCore/ConstantHandling.cpp
Chris Lattner
lattner at cs.uiuc.edu
Mon Jan 12 12:26:02 PST 2004
Changes in directory llvm/lib/VMCore:
ConstantHandling.cpp updated: 1.43 -> 1.44
---
Log message:
Move llvm::ConstantFoldInstruction from here to Transforms/Utils
---
Diffs of the changes: (+0 -58)
Index: llvm/lib/VMCore/ConstantHandling.cpp
diff -u llvm/lib/VMCore/ConstantHandling.cpp:1.43 llvm/lib/VMCore/ConstantHandling.cpp:1.44
--- llvm/lib/VMCore/ConstantHandling.cpp:1.43 Sun Jan 11 17:56:33 2004
+++ llvm/lib/VMCore/ConstantHandling.cpp Mon Jan 12 12:25:03 2004
@@ -19,64 +19,6 @@
#include <cmath>
using namespace llvm;
-// ConstantFoldInstruction - Attempt to constant fold the specified instruction.
-// If successful, the constant result is returned, if not, null is returned.
-//
-Constant *llvm::ConstantFoldInstruction(Instruction *I) {
- if (PHINode *PN = dyn_cast<PHINode>(I)) {
- if (PN->getNumIncomingValues() == 0)
- return Constant::getNullValue(PN->getType());
-
- Constant *Result = dyn_cast<Constant>(PN->getIncomingValue(0));
- if (Result == 0) return 0;
-
- // Handle PHI nodes specially here...
- for (unsigned i = 1, e = PN->getNumIncomingValues(); i != e; ++i)
- if (PN->getIncomingValue(i) != Result)
- return 0; // Not all the same incoming constants...
-
- // If we reach here, all incoming values are the same constant.
- return Result;
- }
-
- Constant *Op0 = 0;
- Constant *Op1 = 0;
-
- if (I->getNumOperands() != 0) { // Get first operand if it's a constant...
- Op0 = dyn_cast<Constant>(I->getOperand(0));
- if (Op0 == 0) return 0; // Not a constant?, can't fold
-
- if (I->getNumOperands() != 1) { // Get second operand if it's a constant...
- Op1 = dyn_cast<Constant>(I->getOperand(1));
- if (Op1 == 0) return 0; // Not a constant?, can't fold
- }
- }
-
- if (isa<BinaryOperator>(I))
- return ConstantExpr::get(I->getOpcode(), Op0, Op1);
-
- switch (I->getOpcode()) {
- case Instruction::Cast:
- return ConstantExpr::getCast(Op0, I->getType());
- case Instruction::Shl:
- case Instruction::Shr:
- return ConstantExpr::getShift(I->getOpcode(), Op0, Op1);
- case Instruction::GetElementPtr: {
- std::vector<Constant*> IdxList;
- IdxList.reserve(I->getNumOperands()-1);
- if (Op1) IdxList.push_back(Op1);
- for (unsigned i = 2, e = I->getNumOperands(); i != e; ++i)
- if (Constant *C = dyn_cast<Constant>(I->getOperand(i)))
- IdxList.push_back(C);
- else
- return 0; // Non-constant operand
- return ConstantExpr::getGetElementPtr(Op0, IdxList);
- }
- default:
- return 0;
- }
-}
-
static unsigned getSize(const Type *Ty) {
unsigned S = Ty->getPrimitiveSize();
return S ? S : 8; // Treat pointers at 8 bytes
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