Fix Bug: ConstProp/2003-05-12-DivideError.ll

[oota-llvm.git] / lib / VMCore / Constants.cpp

diff --git a/lib/VMCore/Constants.cpp b/lib/VMCore/Constants.cpp
index 8464c437fcb4e68734bed325203dbb87e430b051..c519da36a861ecaee3b26f4c775ebca72fc03c79 100644 (file)
--- a/lib/VMCore/Constants.cpp
+++ b/lib/VMCore/Constants.cpp
@@ -5,11 +5,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Constants.h"
+#include "llvm/ConstantHandling.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/iMemory.h"
 #include "llvm/SymbolTable.h"
 #include "llvm/Module.h"
-#include "llvm/SlotCalculator.h"
 #include "Support/StringExtras.h"
 #include <algorithm>
 
@@ -80,7 +80,25 @@ Constant *Constant::getNullValue(const Type *Ty) {
 
   case Type::PointerTyID: 
     return ConstantPointerNull::get(cast<PointerType>(Ty));
+  case Type::StructTyID: {
+    const StructType *ST = cast<StructType>(Ty);
+
+    const StructType::ElementTypes &ETs = ST->getElementTypes();
+    std::vector<Constant*> Elements;
+    Elements.resize(ETs.size());
+    for (unsigned i = 0, e = ETs.size(); i != e; ++i)
+      Elements[i] = Constant::getNullValue(ETs[i]);
+    return ConstantStruct::get(ST, Elements);
+  }
+  case Type::ArrayTyID: {
+    const ArrayType *AT = cast<ArrayType>(Ty);
+    Constant *El = Constant::getNullValue(AT->getElementType());
+    unsigned NumElements = AT->getNumElements();
+    return ConstantArray::get(AT, std::vector<Constant*>(NumElements, El));
+  }
   default:
+    // Function, Type, Label, or Opaque type?
+    assert(0 && "Cannot create a null constant of that type!");
     return 0;
   }
 }
@@ -156,6 +174,13 @@ ConstantIntegral *ConstantIntegral::getAllOnesValue(const Type *Ty) {
   }
 }
 
+bool ConstantUInt::isAllOnesValue() const {
+  unsigned TypeBits = getType()->getPrimitiveSize()*8;
+  uint64_t Val = ~0ULL;                // All ones
+  Val >>= 64-TypeBits;                 // Shift out inappropriate bits
+  return getValue() == Val;
+}
+
 
 //===----------------------------------------------------------------------===//
 //                            ConstantXXX Classes
@@ -394,7 +419,7 @@ void ConstantPointerRef::replaceUsesOfWithOnConstant(Value *From, Value *To) {
 void ConstantExpr::replaceUsesOfWithOnConstant(Value *From, Value *To) {
   assert(isa<Constant>(To) && "Cannot make Constant refer to non-constant!");
 
-  ConstantExpr *Replacement = 0;
+  Constant *Replacement = 0;
   if (getOpcode() == Instruction::GetElementPtr) {
     std::vector<Constant*> Indices;
     Constant *Pointer = cast<Constant>(getOperand(0));
@@ -611,7 +636,9 @@ void ConstantPointerRef::destroyConstant() {
 typedef pair<unsigned, vector<Constant*> > ExprMapKeyType;
 static ValueMap<const ExprMapKeyType, ConstantExpr> ExprConstants;
 
-ConstantExpr *ConstantExpr::getCast(Constant *C, const Type *Ty) {
+Constant *ConstantExpr::getCast(Constant *C, const Type *Ty) {
+  if (Constant *FC = ConstantFoldCastInstruction(C, Ty))
+    return FC;          // Fold a few common cases...
 
   // Look up the constant in the table first to ensure uniqueness
   vector<Constant*> argVec(1, C);
@@ -625,7 +652,11 @@ ConstantExpr *ConstantExpr::getCast(Constant *C, const Type *Ty) {
   return Result;
 }
 
-ConstantExpr *ConstantExpr::get(unsigned Opcode, Constant *C1, Constant *C2) {
+Constant *ConstantExpr::get(unsigned Opcode, Constant *C1, Constant *C2) {
+  
+  if (Constant *FC = ConstantFoldBinaryInstruction(Opcode, C1, C2))
+    return FC;          // Fold a few common cases...
+
   // Look up the constant in the table first to ensure uniqueness
   vector<Constant*> argVec(1, C1); argVec.push_back(C2);
   const ExprMapKeyType &Key = make_pair(Opcode, argVec);
@@ -646,8 +677,10 @@ ConstantExpr *ConstantExpr::get(unsigned Opcode, Constant *C1, Constant *C2) {
   return Result;
 }
 
-ConstantExpr *ConstantExpr::getGetElementPtr(Constant *C,
-                                        const std::vector<Constant*> &IdxList) {
+Constant *ConstantExpr::getGetElementPtr(Constant *C,
+                                         const std::vector<Constant*> &IdxList){
+  if (Constant *FC = ConstantFoldGetElementPtr(C, IdxList))
+    return FC;          // Fold a few common cases...
   const Type *Ty = C->getType();
 
   // Look up the constant in the table first to ensure uniqueness
@@ -685,27 +718,25 @@ const char *ConstantExpr::getOpcodeName() const {
   return Instruction::getOpcodeName(getOpcode());
 }
 
+unsigned Constant::mutateReferences(Value *OldV, Value *NewV) {
+  // Uses of constant pointer refs are global values, not constants!
+  if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(this)) {
+    GlobalValue *NewGV = cast<GlobalValue>(NewV);
+    GlobalValue *OldGV = CPR->getValue();
 
-//---- ConstantPointerRef::mutateReferences() implementation...
-//
-unsigned ConstantPointerRef::mutateReferences(Value *OldV, Value *NewV) {
-  assert(getValue() == OldV && "Cannot mutate old value if I'm not using it!");
-  GlobalValue *NewGV = cast<GlobalValue>(NewV);
-  getValue()->getParent()->mutateConstantPointerRef(getValue(), NewGV);
-  Operands[0] = NewGV;
-  return 1;
-}
-
+    assert(OldGV == OldV && "Cannot mutate old value if I'm not using it!");
 
-//---- ConstantPointerExpr::mutateReferences() implementation...
-//
-unsigned ConstantExpr::mutateReferences(Value* OldV, Value *NewV) {
-  unsigned NumReplaced = 0;
-  Constant *NewC = cast<Constant>(NewV);
-  for (unsigned i = 0, N = getNumOperands(); i != N; ++i)
-    if (Operands[i] == OldV) {
-      ++NumReplaced;
-      Operands[i] = NewC;
-    }
-  return NumReplaced;
+    OldGV->getParent()->mutateConstantPointerRef(OldGV, NewGV);
+    Operands[0] = NewGV;
+    return 1;
+  } else {
+    Constant *NewC = cast<Constant>(NewV);
+    unsigned NumReplaced = 0;
+    for (unsigned i = 0, N = getNumOperands(); i != N; ++i)
+      if (Operands[i] == OldV) {
+        ++NumReplaced;
+        Operands[i] = NewC;
+      }
+    return NumReplaced;
+  }
 }