diff options
Diffstat (limited to 'llvm/lib/Analysis/ValueTracking.cpp')
-rw-r--r-- | llvm/lib/Analysis/ValueTracking.cpp | 14 |
1 files changed, 2 insertions, 12 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index 904b069..07113e18 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -1127,19 +1127,9 @@ static void computeKnownBitsFromOperator(const Operator *I, break; } case Instruction::UDiv: { - // For the purposes of computing leading zeros we can conservatively - // treat a udiv as a logical right shift by the power of 2 known to - // be less than the denominator. - computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q); - unsigned LeadZ = Known2.countMinLeadingZeros(); - - Known2.resetAll(); + computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); - unsigned RHSMaxLeadingZeros = Known2.countMaxLeadingZeros(); - if (RHSMaxLeadingZeros != BitWidth) - LeadZ = std::min(BitWidth, LeadZ + BitWidth - RHSMaxLeadingZeros - 1); - - Known.Zero.setHighBits(LeadZ); + Known = KnownBits::udiv(Known, Known2); break; } case Instruction::Select: { |