diff options
| -rw-r--r-- | llvm/lib/Analysis/LazyValueInfo.cpp | 27 | ||||
| -rw-r--r-- | llvm/test/Transforms/CorrelatedValuePropagation/basic.ll | 23 |
2 files changed, 39 insertions, 11 deletions
diff --git a/llvm/lib/Analysis/LazyValueInfo.cpp b/llvm/lib/Analysis/LazyValueInfo.cpp index 6bc639cf8b2..3b0ffb8d400 100644 --- a/llvm/lib/Analysis/LazyValueInfo.cpp +++ b/llvm/lib/Analysis/LazyValueInfo.cpp @@ -1063,22 +1063,27 @@ bool LazyValueInfoCache::solveBlockValueCast(LVILatticeVal &BBLV, bool LazyValueInfoCache::solveBlockValueBinaryOp(LVILatticeVal &BBLV, Instruction *BBI, BasicBlock *BB) { + + assert(BBI->getOperand(0)->getType()->isSized() && + "all operands to binary operators are sized"); - // Figure out the range of the LHS. If that fails, bail. - if (!hasBlockValue(BBI->getOperand(0), BB)) { + // Figure out the range of the LHS. If that fails, use a conservative range, + // but apply the transfer rule anyways. This lets us pick up facts from + // expressions like "and i32 (call i32 @foo()), 32" + if (!hasBlockValue(BBI->getOperand(0), BB)) if (pushBlockValue(std::make_pair(BB, BBI->getOperand(0)))) + // More work to do before applying this transfer rule. return false; - BBLV.markOverdefined(); - return true; - } - LVILatticeVal LHSVal = getBlockValue(BBI->getOperand(0), BB); - intersectAssumeBlockValueConstantRange(BBI->getOperand(0), LHSVal, BBI); - if (!LHSVal.isConstantRange()) { - BBLV.markOverdefined(); - return true; + const unsigned OperandBitWidth = + DL.getTypeSizeInBits(BBI->getOperand(0)->getType()); + ConstantRange LHSRange = ConstantRange(OperandBitWidth); + if (hasBlockValue(BBI->getOperand(0), BB)) { + LVILatticeVal LHSVal = getBlockValue(BBI->getOperand(0), BB); + intersectAssumeBlockValueConstantRange(BBI->getOperand(0), LHSVal, BBI); + if (LHSVal.isConstantRange()) + LHSRange = LHSVal.getConstantRange(); } - ConstantRange LHSRange = LHSVal.getConstantRange(); ConstantInt *RHS = cast<ConstantInt>(BBI->getOperand(1)); ConstantRange RHSRange = ConstantRange(RHS->getValue()); diff --git a/llvm/test/Transforms/CorrelatedValuePropagation/basic.ll b/llvm/test/Transforms/CorrelatedValuePropagation/basic.ll index 9f41807cc55..d0a17306c6b 100644 --- a/llvm/test/Transforms/CorrelatedValuePropagation/basic.ll +++ b/llvm/test/Transforms/CorrelatedValuePropagation/basic.ll @@ -440,3 +440,26 @@ entry: exit: ret i1 %cmp } + + +define i1 @and_unknown(i32 %a) { +; CHECK-LABEL: @and_unknown +; CHECK: ret i1 true +entry: + %and = and i32 %a, 128 + %cmp = icmp sle i32 %and, 128 + br label %exit +exit: + ret i1 %cmp +} + +define i1 @lshr_unknown(i32 %a) { +; CHECK-LABEL: @lshr_unknown +; CHECK: ret i1 true +entry: + %and = lshr i32 %a, 30 + %cmp = icmp sle i32 %and, 128 + br label %exit +exit: + ret i1 %cmp +} |
