1 files changed, 106 insertions, 18 deletions

diff --git a/lib/VMCore/Constants.cpp b/lib/VMCore/Constants.cpp
index 02c33528ecfb..000a063cc1bb 100644
--- a/lib/VMCore/Constants.cpp
+++ b/lib/VMCore/Constants.cpp
@@ -7,7 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This file implements the Constant* classes...
+// This file implements the Constant* classes.
 //
 //===----------------------------------------------------------------------===//
 
@@ -29,9 +29,6 @@
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/GetElementPtrTypeIterator.h"
-#include "llvm/System/Mutex.h"
-#include "llvm/System/RWMutex.h"
-#include "llvm/System/Threading.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/SmallVector.h"
 #include <algorithm>
@@ -44,7 +41,7 @@ using namespace llvm;
 
 // Constructor to create a '0' constant of arbitrary type...
 static const uint64_t zero[2] = {0, 0};
-Constant* Constant::getNullValue(const Type* Ty) {
+Constant *Constant::getNullValue(const Type *Ty) {
   switch (Ty->getTypeID()) {
   case Type::IntegerTyID:
     return ConstantInt::get(Ty, 0);
@@ -72,7 +69,7 @@ Constant* Constant::getNullValue(const Type* Ty) {
   }
 }
 
-Constant* Constant::getIntegerValue(const Type* Ty, const APInt &V) {
+Constant* Constant::getIntegerValue(const Type *Ty, const APInt &V) {
   const Type *ScalarTy = Ty->getScalarType();
 
   // Create the base integer constant.
@@ -89,13 +86,13 @@ Constant* Constant::getIntegerValue(const Type* Ty, const APInt &V) {
   return C;
 }
 
-Constant* Constant::getAllOnesValue(const Type* Ty) {
-  if (const IntegerType* ITy = dyn_cast<IntegerType>(Ty))
+Constant* Constant::getAllOnesValue(const Type *Ty) {
+  if (const IntegerType *ITy = dyn_cast<IntegerType>(Ty))
     return ConstantInt::get(Ty->getContext(),
                             APInt::getAllOnesValue(ITy->getBitWidth()));
   
   std::vector<Constant*> Elts;
-  const VectorType* VTy = cast<VectorType>(Ty);
+  const VectorType *VTy = cast<VectorType>(Ty);
   Elts.resize(VTy->getNumElements(), getAllOnesValue(VTy->getElementType()));
   assert(Elts[0] && "Not a vector integer type!");
   return cast<ConstantVector>(ConstantVector::get(Elts));
@@ -140,7 +137,7 @@ bool Constant::canTrap() const {
   
   // ConstantExpr traps if any operands can trap. 
   for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
-    if (getOperand(i)->canTrap()) 
+    if (CE->getOperand(i)->canTrap()) 
       return true;
 
   // Otherwise, only specific operations can trap.
@@ -154,12 +151,27 @@ bool Constant::canTrap() const {
   case Instruction::SRem:
   case Instruction::FRem:
     // Div and rem can trap if the RHS is not known to be non-zero.
-    if (!isa<ConstantInt>(getOperand(1)) || getOperand(1)->isNullValue())
+    if (!isa<ConstantInt>(CE->getOperand(1)) ||CE->getOperand(1)->isNullValue())
       return true;
     return false;
   }
 }
 
+/// isConstantUsed - Return true if the constant has users other than constant
+/// exprs and other dangling things.
+bool Constant::isConstantUsed() const {
+  for (use_const_iterator UI = use_begin(), E = use_end(); UI != E; ++UI) {
+    const Constant *UC = dyn_cast<Constant>(*UI);
+    if (UC == 0 || isa<GlobalValue>(UC))
+      return true;
+    
+    if (UC->isConstantUsed())
+      return true;
+  }
+  return false;
+}
+
+
 
 /// getRelocationInfo - This method classifies the entry according to
 /// whether or not it may generate a relocation entry.  This must be
@@ -182,9 +194,13 @@ Constant::PossibleRelocationsTy Constant::getRelocationInfo() const {
     return GlobalRelocations;    // Global reference.
   }
   
+  if (const BlockAddress *BA = dyn_cast<BlockAddress>(this))
+    return BA->getFunction()->getRelocationInfo();
+  
   PossibleRelocationsTy Result = NoRelocation;
   for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
-    Result = std::max(Result, getOperand(i)->getRelocationInfo());
+    Result = std::max(Result,
+                      cast<Constant>(getOperand(i))->getRelocationInfo());
   
   return Result;
 }
@@ -987,7 +1003,7 @@ Constant *ConstantVector::getSplatValue() {
   return Elt;
 }
 
-//---- ConstantPointerNull::get() implementation...
+//---- ConstantPointerNull::get() implementation.
 //
 
 ConstantPointerNull *ConstantPointerNull::get(const PointerType *Ty) {
@@ -1004,23 +1020,95 @@ void ConstantPointerNull::destroyConstant() {
 }
 
 
-//---- UndefValue::get() implementation...
+//---- UndefValue::get() implementation.
 //
 
 UndefValue *UndefValue::get(const Type *Ty) {
-  // Implicitly locked.
   return Ty->getContext().pImpl->UndefValueConstants.getOrCreate(Ty, 0);
 }
 
 // destroyConstant - Remove the constant from the constant table.
 //
 void UndefValue::destroyConstant() {
-  // Implicitly locked.
   getType()->getContext().pImpl->UndefValueConstants.remove(this);
   destroyConstantImpl();
 }
 
-//---- ConstantExpr::get() implementations...
+//---- BlockAddress::get() implementation.
+//
+
+BlockAddress *BlockAddress::get(BasicBlock *BB) {
+  assert(BB->getParent() != 0 && "Block must have a parent");
+  return get(BB->getParent(), BB);
+}
+
+BlockAddress *BlockAddress::get(Function *F, BasicBlock *BB) {
+  BlockAddress *&BA =
+    F->getContext().pImpl->BlockAddresses[std::make_pair(F, BB)];
+  if (BA == 0)
+    BA = new BlockAddress(F, BB);
+  
+  assert(BA->getFunction() == F && "Basic block moved between functions");
+  return BA;
+}
+
+BlockAddress::BlockAddress(Function *F, BasicBlock *BB)
+: Constant(Type::getInt8PtrTy(F->getContext()), Value::BlockAddressVal,
+           &Op<0>(), 2) {
+  setOperand(0, F);
+  setOperand(1, BB);
+  BB->AdjustBlockAddressRefCount(1);
+}
+
+
+// destroyConstant - Remove the constant from the constant table.
+//
+void BlockAddress::destroyConstant() {
+  getFunction()->getType()->getContext().pImpl
+    ->BlockAddresses.erase(std::make_pair(getFunction(), getBasicBlock()));
+  getBasicBlock()->AdjustBlockAddressRefCount(-1);
+  destroyConstantImpl();
+}
+
+void BlockAddress::replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U) {
+  // This could be replacing either the Basic Block or the Function.  In either
+  // case, we have to remove the map entry.
+  Function *NewF = getFunction();
+  BasicBlock *NewBB = getBasicBlock();
+  
+  if (U == &Op<0>())
+    NewF = cast<Function>(To);
+  else
+    NewBB = cast<BasicBlock>(To);
+  
+  // See if the 'new' entry already exists, if not, just update this in place
+  // and return early.
+  BlockAddress *&NewBA =
+    getContext().pImpl->BlockAddresses[std::make_pair(NewF, NewBB)];
+  if (NewBA == 0) {
+    getBasicBlock()->AdjustBlockAddressRefCount(-1);
+    
+    // Remove the old entry, this can't cause the map to rehash (just a
+    // tombstone will get added).
+    getContext().pImpl->BlockAddresses.erase(std::make_pair(getFunction(),
+                                                            getBasicBlock()));
+    NewBA = this;
+    setOperand(0, NewF);
+    setOperand(1, NewBB);
+    getBasicBlock()->AdjustBlockAddressRefCount(1);
+    return;
+  }
+
+  // Otherwise, I do need to replace this with an existing value.
+  assert(NewBA != this && "I didn't contain From!");
+  
+  // Everyone using this now uses the replacement.
+  uncheckedReplaceAllUsesWith(NewBA);
+  
+  destroyConstant();
+}
+
+//---- ConstantExpr::get() implementations.
 //
 
 /// This is a utility function to handle folding of casts and lookup of the
@@ -1838,7 +1926,7 @@ const char *ConstantExpr::getOpcodeName() const {
 /// single invocation handles all 1000 uses.  Handling them one at a time would
 /// work, but would be really slow because it would have to unique each updated
 /// array instance.
-
+///
 void ConstantArray::replaceUsesOfWithOnConstant(Value *From, Value *To,
                                                 Use *U) {
   assert(isa<Constant>(To) && "Cannot make Constant refer to non-constant!");