///
PHINode *getCanonicalInductionVariable() const;
- /// getCanonicalInductionVariableIncrement - Return the LLVM value that holds
- /// the canonical induction variable value for the "next" iteration of the
- /// loop. This always succeeds if getCanonicalInductionVariable succeeds.
- ///
- Instruction *getCanonicalInductionVariableIncrement() const;
-
/// getTripCount - Return a loop-invariant LLVM value indicating the number of
/// times the loop will be executed. Note that this means that the backedge
/// of the loop executes N-1 times. If the trip-count cannot be determined,
return 0;
}
-/// getCanonicalInductionVariableIncrement - Return the LLVM value that holds
-/// the canonical induction variable value for the "next" iteration of the
-/// loop. This always succeeds if getCanonicalInductionVariable succeeds.
-///
-Instruction *Loop::getCanonicalInductionVariableIncrement() const {
- if (PHINode *PN = getCanonicalInductionVariable()) {
- bool P1InLoop = contains(PN->getIncomingBlock(1));
- return cast<Instruction>(PN->getIncomingValue(P1InLoop));
- }
- return 0;
-}
-
/// getTripCount - Return a loop-invariant LLVM value indicating the number of
/// times the loop will be executed. Note that this means that the backedge
/// of the loop executes N-1 times. If the trip-count cannot be determined,
Value *Loop::getTripCount() const {
// Canonical loops will end with a 'cmp ne I, V', where I is the incremented
// canonical induction variable and V is the trip count of the loop.
- Instruction *Inc = getCanonicalInductionVariableIncrement();
- if (Inc == 0) return 0;
- PHINode *IV = cast<PHINode>(Inc->getOperand(0));
+ PHINode *IV = getCanonicalInductionVariable();
+ if (IV == 0 || IV->getNumIncomingValues() != 2) return 0;
- BasicBlock *BackedgeBlock =
- IV->getIncomingBlock(contains(IV->getIncomingBlock(1)));
+ bool P0InLoop = contains(IV->getIncomingBlock(0));
+ Value *Inc = IV->getIncomingValue(!P0InLoop);
+ BasicBlock *BackedgeBlock = IV->getIncomingBlock(!P0InLoop);
if (BranchInst *BI = dyn_cast<BranchInst>(BackedgeBlock->getTerminator()))
if (BI->isConditional()) {