#include "llvm/BasicBlock.h"
#include "llvm/Constants.h"
#include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
#include "llvm/LLVMContext.h"
#include "llvm/Type.h"
#include "llvm/ADT/STLExtras.h"
// Explicit instantiation of SymbolTableListTraits since some of the methods
// are not in the public header file...
-template class SymbolTableListTraits<Instruction, BasicBlock>;
+template class llvm::SymbolTableListTraits<Instruction, BasicBlock>;
-BasicBlock::BasicBlock(const Twine &Name, Function *NewParent,
+BasicBlock::BasicBlock(LLVMContext &C, const Twine &Name, Function *NewParent,
BasicBlock *InsertBefore)
- : Value(Type::LabelTy, Value::BasicBlockVal), Parent(0) {
+ : Value(Type::getLabelTy(C), Value::BasicBlockVal), Parent(0) {
// Make sure that we get added to a function
LeakDetector::addGarbageObject(this);
} else if (NewParent) {
NewParent->getBasicBlockList().push_back(this);
}
-
+
setName(Name);
}
BasicBlock::~BasicBlock() {
+ // If the address of the block is taken and it is being deleted (e.g. because
+ // it is dead), this means that there is either a dangling constant expr
+ // hanging off the block, or an undefined use of the block (source code
+ // expecting the address of a label to keep the block alive even though there
+ // is no indirect branch). Handle these cases by zapping the BlockAddress
+ // nodes. There are no other possible uses at this point.
+ if (hasAddressTaken()) {
+ assert(!use_empty() && "There should be at least one blockaddress!");
+ Constant *Replacement =
+ ConstantInt::get(llvm::Type::getInt32Ty(getContext()), 1);
+ while (!use_empty()) {
+ BlockAddress *BA = cast<BlockAddress>(use_back());
+ BA->replaceAllUsesWith(ConstantExpr::getIntToPtr(Replacement,
+ BA->getType()));
+ BA->destroyConstant();
+ }
+ }
+
assert(getParent() == 0 && "BasicBlock still linked into the program!");
dropAllReferences();
InstList.clear();
return &*i;
}
+Instruction* BasicBlock::getFirstNonPHIOrDbg() {
+ BasicBlock::iterator i = begin();
+ // All valid basic blocks should have a terminator,
+ // which is not a PHINode. If we have an invalid basic
+ // block we'll get an assertion failure when dereferencing
+ // a past-the-end iterator.
+ while (isa<PHINode>(i) || isa<DbgInfoIntrinsic>(i)) ++i;
+ return &*i;
+}
+
+Instruction* BasicBlock::getFirstNonPHIOrDbgOrLifetime() {
+ // All valid basic blocks should have a terminator,
+ // which is not a PHINode. If we have an invalid basic
+ // block we'll get an assertion failure when dereferencing
+ // a past-the-end iterator.
+ BasicBlock::iterator i = begin();
+ for (;; ++i) {
+ if (isa<PHINode>(i) || isa<DbgInfoIntrinsic>(i))
+ continue;
+
+ const IntrinsicInst *II = dyn_cast<IntrinsicInst>(i);
+ if (!II)
+ break;
+ if (II->getIntrinsicID() != Intrinsic::lifetime_start &&
+ II->getIntrinsicID() != Intrinsic::lifetime_end)
+ break;
+ }
+ return &*i;
+}
+
+BasicBlock::iterator BasicBlock::getFirstInsertionPt() {
+ iterator InsertPt = getFirstNonPHI();
+ if (isa<LandingPadInst>(InsertPt)) ++InsertPt;
+ return InsertPt;
+}
+
void BasicBlock::dropAllReferences() {
for(iterator I = begin(), E = end(); I != E; ++I)
I->dropAllReferences();
/// getUniquePredecessor - If this basic block has a unique predecessor block,
/// return the block, otherwise return a null pointer.
-/// Note that unique predecessor doesn't mean single edge, there can be
-/// multiple edges from the unique predecessor to this block (for example
+/// Note that unique predecessor doesn't mean single edge, there can be
+/// multiple edges from the unique predecessor to this block (for example
/// a switch statement with multiple cases having the same destination).
BasicBlock *BasicBlock::getUniquePredecessor() {
pred_iterator PI = pred_begin(this), E = pred_end(this);
// If the PHI _HAD_ two uses, replace PHI node with its now *single* value
if (max_idx == 2) {
- if (PN->getOperand(0) != PN)
- PN->replaceAllUsesWith(PN->getOperand(0));
+ if (PN->getIncomingValue(0) != PN)
+ PN->replaceAllUsesWith(PN->getIncomingValue(0));
else
// We are left with an infinite loop with no entries: kill the PHI.
PN->replaceAllUsesWith(UndefValue::get(PN->getType()));
// If all incoming values to the Phi are the same, we can replace the Phi
// with that value.
Value* PNV = 0;
- if (!DontDeleteUselessPHIs && (PNV = PN->hasConstantValue())) {
- PN->replaceAllUsesWith(PNV);
- PN->eraseFromParent();
- }
+ if (!DontDeleteUselessPHIs && (PNV = PN->hasConstantValue()))
+ if (PNV != PN) {
+ PN->replaceAllUsesWith(PNV);
+ PN->eraseFromParent();
+ }
}
}
}
assert(I != InstList.end() &&
"Trying to get me to create degenerate basic block!");
- BasicBlock *InsertBefore = next(Function::iterator(this))
+ BasicBlock *InsertBefore = llvm::next(Function::iterator(this))
.getNodePtrUnchecked();
- BasicBlock *New = BasicBlock::Create(BBName, getParent(), InsertBefore);
+ BasicBlock *New = BasicBlock::Create(getContext(), BBName,
+ getParent(), InsertBefore);
// Move all of the specified instructions from the original basic block into
// the new basic block.
}
return New;
}
+
+void BasicBlock::replaceSuccessorsPhiUsesWith(BasicBlock *New) {
+ TerminatorInst *TI = getTerminator();
+ if (!TI)
+ // Cope with being called on a BasicBlock that doesn't have a terminator
+ // yet. Clang's CodeGenFunction::EmitReturnBlock() likes to do this.
+ return;
+ for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i) {
+ BasicBlock *Succ = TI->getSuccessor(i);
+ // N.B. Succ might not be a complete BasicBlock, so don't assume
+ // that it ends with a non-phi instruction.
+ for (iterator II = Succ->begin(), IE = Succ->end(); II != IE; ++II) {
+ PHINode *PN = dyn_cast<PHINode>(II);
+ if (!PN)
+ break;
+ int i;
+ while ((i = PN->getBasicBlockIndex(this)) >= 0)
+ PN->setIncomingBlock(i, New);
+ }
+ }
+}
+
+/// isLandingPad - Return true if this basic block is a landing pad. I.e., it's
+/// the destination of the 'unwind' edge of an invoke instruction.
+bool BasicBlock::isLandingPad() const {
+ return isa<LandingPadInst>(getFirstNonPHI());
+}
+
+/// getLandingPadInst() - Return the landingpad instruction associated with
+/// the landing pad.
+LandingPadInst *BasicBlock::getLandingPadInst() {
+ return dyn_cast<LandingPadInst>(getFirstNonPHI());
+}