diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp index 73dc141d97e..b36eadf6aad 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -2030,15 +2030,10 @@ Instruction *InstCombiner::foldICmpShlConstant(ICmpInst &Cmp, Instruction *Shl, if (cast<BinaryOperator>(Shl)->hasNoSignedWrap() && isSignTest(Pred, *C)) return new ICmpInst(Pred, X, Constant::getNullValue(X->getType())); - // FIXME: This check restricts all folds under here to scalar types. - ConstantInt *RHS = dyn_cast<ConstantInt>(Cmp.getOperand(1)); - if (!RHS) - return nullptr; - // Otherwise, if this is a comparison of the sign bit, simplify to and/test. bool TrueIfSigned = false; if (Shl->hasOneUse() && isSignBitCheck(Pred, *C, TrueIfSigned)) { - // (X << 31) <s 0 --> (X&1) != 0 + // (X << 31) <s 0 --> (X & 1) != 0 Constant *Mask = ConstantInt::get( X->getType(), APInt::getOneBitSet(TypeBits, TypeBits - ShiftAmt->getZExtValue() - 1)); @@ -2047,6 +2042,11 @@ Instruction *InstCombiner::foldICmpShlConstant(ICmpInst &Cmp, Instruction *Shl, And, Constant::getNullValue(And->getType())); } + // FIXME: This check restricts all folds under here to scalar types. + ConstantInt *RHS = dyn_cast<ConstantInt>(Cmp.getOperand(1)); + if (!RHS) + return nullptr; + // Transform (icmp pred iM (shl iM %v, N), CI) // -> (icmp pred i(M-N) (trunc %v iM to i(M-N)), (trunc (CI>>N)) // Transform the shl to a trunc if (trunc (CI>>N)) has no loss and M-N. |
