diff options
| -rw-r--r-- | llvm/lib/Analysis/LazyValueInfo.cpp | 41 |
1 files changed, 16 insertions, 25 deletions
diff --git a/llvm/lib/Analysis/LazyValueInfo.cpp b/llvm/lib/Analysis/LazyValueInfo.cpp index f58e11e2df7..f41978f18ee 100644 --- a/llvm/lib/Analysis/LazyValueInfo.cpp +++ b/llvm/lib/Analysis/LazyValueInfo.cpp @@ -859,9 +859,8 @@ bool LazyValueInfoCache::solveBlockValuePHINode(LVILatticeVal &BBLV, return true; } -static bool getValueFromCondition(Value *Val, Value *Cond, - LVILatticeVal &Result, - bool isTrueDest = true); +static LVILatticeVal getValueFromCondition(Value *Val, Value *Cond, + bool isTrueDest = true); // If we can determine a constraint on the value given conditions assumed by // the program, intersect those constraints with BBLV @@ -879,9 +878,7 @@ void LazyValueInfoCache::intersectAssumeBlockValueConstantRange(Value *Val, if (!isValidAssumeForContext(I, BBI, DT)) continue; - LVILatticeVal Result; - if (getValueFromCondition(Val, I->getArgOperand(0), Result)) - BBLV = intersect(BBLV, Result); + BBLV = intersect(BBLV, getValueFromCondition(Val, I->getArgOperand(0))); } } @@ -952,14 +949,10 @@ bool LazyValueInfoCache::solveBlockValueSelect(LVILatticeVal &BBLV, // condition itself? This shows up with idioms like e.g. select(a > 5, a, 5). // TODO: We could potentially refine an overdefined true value above. Value *Cond = SI->getCondition(); - LVILatticeVal TrueValTaken, FalseValTaken; - if (!getValueFromCondition(SI->getTrueValue(), Cond, TrueValTaken, true)) - TrueValTaken.markOverdefined(); - if (!getValueFromCondition(SI->getFalseValue(), Cond, FalseValTaken, false)) - FalseValTaken.markOverdefined(); - - TrueVal = intersect(TrueVal, TrueValTaken); - FalseVal = intersect(FalseVal, FalseValTaken); + TrueVal = intersect(TrueVal, + getValueFromCondition(SI->getTrueValue(), Cond, true)); + FalseVal = intersect(FalseVal, + getValueFromCondition(SI->getFalseValue(), Cond, false)); // Handle clamp idioms such as: // %24 = constantrange<0, 17> @@ -1174,14 +1167,13 @@ bool LazyValueInfoCache::solveBlockValueBinaryOp(LVILatticeVal &BBLV, return true; } -bool getValueFromCondition(Value *Val, Value *Cond, LVILatticeVal &Result, - bool isTrueDest) { +LVILatticeVal getValueFromCondition(Value *Val, Value *Cond, bool isTrueDest) { assert(Cond && "precondition"); // For now we only support ICmpInst conditions ICmpInst *ICI = dyn_cast<ICmpInst>(Cond); if (!ICI) - return false; + return LVILatticeVal::getOverdefined(); Value *LHS = ICI->getOperand(0); Value *RHS = ICI->getOperand(1); @@ -1192,15 +1184,14 @@ bool getValueFromCondition(Value *Val, Value *Cond, LVILatticeVal &Result, // We know that V has the RHS constant if this is a true SETEQ or // false SETNE. if (isTrueDest == (Predicate == ICmpInst::ICMP_EQ)) - Result = LVILatticeVal::get(cast<Constant>(RHS)); + return LVILatticeVal::get(cast<Constant>(RHS)); else - Result = LVILatticeVal::getNot(cast<Constant>(RHS)); - return true; + return LVILatticeVal::getNot(cast<Constant>(RHS)); } } if (!Val->getType()->isIntegerTy()) - return false; + return LVILatticeVal::getOverdefined(); // Use ConstantRange::makeAllowedICmpRegion in order to determine the possible // range of Val guaranteed by the condition. Recognize comparisons in the from @@ -1236,11 +1227,10 @@ bool getValueFromCondition(Value *Val, Value *Cond, LVILatticeVal &Result, if (Offset) // Apply the offset from above. TrueValues = TrueValues.subtract(Offset->getValue()); - Result = LVILatticeVal::getRange(std::move(TrueValues)); - return true; + return LVILatticeVal::getRange(std::move(TrueValues)); } - return false; + return LVILatticeVal::getOverdefined(); } /// \brief Compute the value of Val on the edge BBFrom -> BBTo. Returns false if @@ -1269,7 +1259,8 @@ static bool getEdgeValueLocal(Value *Val, BasicBlock *BBFrom, // If the condition of the branch is an equality comparison, we may be // able to infer the value. - if (getValueFromCondition(Val, BI->getCondition(), Result, isTrueDest)) + Result = getValueFromCondition(Val, BI->getCondition(), isTrueDest); + if (!Result.isOverdefined()) return true; } } |
