diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -1208,7 +1208,8 @@ case Instruction::UDiv: { computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); - Known = KnownBits::udiv(Known, Known2); + Known = + KnownBits::udiv(Known, Known2, Q.IIQ.isExact(cast(I))); break; } case Instruction::Select: { diff --git a/llvm/test/Analysis/ValueTracking/knownbits-div.ll b/llvm/test/Analysis/ValueTracking/knownbits-div.ll --- a/llvm/test/Analysis/ValueTracking/knownbits-div.ll +++ b/llvm/test/Analysis/ValueTracking/knownbits-div.ll @@ -197,12 +197,7 @@ define i1 @udiv_exact_odd_odd(i8 %x, i8 %y) { ; CHECK-LABEL: @udiv_exact_odd_odd( -; CHECK-NEXT: [[NUM:%.*]] = or i8 [[X:%.*]], 1 -; CHECK-NEXT: [[DENUM:%.*]] = or i8 [[Y:%.*]], 1 -; CHECK-NEXT: [[DIV:%.*]] = udiv exact i8 [[NUM]], [[DENUM]] -; CHECK-NEXT: [[AND:%.*]] = and i8 [[DIV]], 1 -; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[AND]], 0 -; CHECK-NEXT: ret i1 [[R]] +; CHECK-NEXT: ret i1 false ; %num = or i8 %x, 1 %denum = or i8 %y, 1 @@ -214,12 +209,7 @@ define i1 @udiv_exact_even_odd(i8 %x, i8 %y) { ; CHECK-LABEL: @udiv_exact_even_odd( -; CHECK-NEXT: [[NUM:%.*]] = and i8 [[X:%.*]], -2 -; CHECK-NEXT: [[DENUM:%.*]] = or i8 [[Y:%.*]], 1 -; CHECK-NEXT: [[DIV:%.*]] = udiv exact i8 [[NUM]], [[DENUM]] -; CHECK-NEXT: [[AND:%.*]] = and i8 [[DIV]], 1 -; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[AND]], 1 -; CHECK-NEXT: ret i1 [[R]] +; CHECK-NEXT: ret i1 false ; %num = and i8 %x, -2 %denum = or i8 %y, 1