Index: lib/Transforms/InstCombine/InstCombineCompares.cpp =================================================================== --- lib/Transforms/InstCombine/InstCombineCompares.cpp +++ lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -4624,34 +4624,51 @@ } // Transform pattern like: -// (1 << Y) u<= X -// (1 << Y) u> X +// (1 << Y) u<= X or ~(-1 << Y) u< X +// (1 << Y) u> X or ~(-1 << Y) u>= X // Into: // (X l>> Y) != 0 // (X l>> Y) == 0 static Instruction *foldICmpWithHighBitMask(ICmpInst &Cmp, InstCombiner::BuilderTy &Builder) { - ICmpInst::Predicate Pred; + ICmpInst::Predicate Pred, NewPred; Value *X, *Y; - if (!match(&Cmp, - m_c_ICmp(Pred, m_OneUse(m_Shl(m_One(), m_Value(Y))), m_Value(X)))) - return nullptr; + if (match(&Cmp, + m_c_ICmp(Pred, m_OneUse(m_Shl(m_One(), m_Value(Y))), m_Value(X)))) { + // We want X to be the icmp's second operand, so swap predicate if it isn't. + if (Cmp.getOperand(0) == X) + Pred = Cmp.getSwappedPredicate(); - // We want X to be the icmp's second operand, so swap predicate if it is not. - if (Cmp.getOperand(0) == X) - Pred = Cmp.getSwappedPredicate(); + switch (Pred) { + case ICmpInst::ICMP_ULE: + NewPred = ICmpInst::ICMP_NE; + break; + case ICmpInst::ICMP_UGT: + NewPred = ICmpInst::ICMP_EQ; + break; + default: + return nullptr; + } + } else if (match(&Cmp, + m_c_ICmp(Pred, + m_OneUse(m_Not(m_Shl(m_AllOnes(), m_Value(Y)))), + m_Value(X)))) { + // We want X to be the icmp's second operand, so swap predicate if it isn't. + if (Cmp.getOperand(0) == X) + Pred = Cmp.getSwappedPredicate(); - ICmpInst::Predicate NewPred; - switch (Pred) { - case ICmpInst::ICMP_ULE: - NewPred = ICmpInst::ICMP_NE; - break; - case ICmpInst::ICMP_UGT: - NewPred = ICmpInst::ICMP_EQ; - break; - default: + switch (Pred) { + case ICmpInst::ICMP_ULT: + NewPred = ICmpInst::ICMP_NE; + break; + case ICmpInst::ICMP_UGE: + NewPred = ICmpInst::ICMP_EQ; + break; + default: + return nullptr; + } + } else return nullptr; - } Value *NewX = Builder.CreateLShr(X, Y, X->getName() + ".highbits"); Constant *Zero = Constant::getNullValue(NewX->getType()); Index: test/Transforms/InstCombine/icmp-uge-of-not-of-shl-allones-by-bits-and-val-to-icmp-eq-of-lshr-val-by-bits-and-0.ll =================================================================== --- test/Transforms/InstCombine/icmp-uge-of-not-of-shl-allones-by-bits-and-val-to-icmp-eq-of-lshr-val-by-bits-and-0.ll +++ test/Transforms/InstCombine/icmp-uge-of-not-of-shl-allones-by-bits-and-val-to-icmp-eq-of-lshr-val-by-bits-and-0.ll @@ -14,9 +14,8 @@ define i1 @p0(i8 %val, i8 %bits) { ; CHECK-LABEL: @p0( -; CHECK-NEXT: [[T0:%.*]] = shl i8 -1, [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor i8 [[T0]], -1 -; CHECK-NEXT: [[R:%.*]] = icmp uge i8 [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr i8 [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[VAL_HIGHBITS]], 0 ; CHECK-NEXT: ret i1 [[R]] ; %t0 = shl i8 -1, %bits @@ -31,9 +30,8 @@ define <2 x i1> @p1_vec(<2 x i8> %val, <2 x i8> %bits) { ; CHECK-LABEL: @p1_vec( -; CHECK-NEXT: [[T0:%.*]] = shl <2 x i8> , [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor <2 x i8> [[T0]], -; CHECK-NEXT: [[R:%.*]] = icmp uge <2 x i8> [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr <2 x i8> [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp eq <2 x i8> [[VAL_HIGHBITS]], zeroinitializer ; CHECK-NEXT: ret <2 x i1> [[R]] ; %t0 = shl <2 x i8> , %bits @@ -44,9 +42,8 @@ define <3 x i1> @p2_vec_undef0(<3 x i8> %val, <3 x i8> %bits) { ; CHECK-LABEL: @p2_vec_undef0( -; CHECK-NEXT: [[T0:%.*]] = shl <3 x i8> , [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor <3 x i8> [[T0]], -; CHECK-NEXT: [[R:%.*]] = icmp uge <3 x i8> [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr <3 x i8> [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp eq <3 x i8> [[VAL_HIGHBITS]], zeroinitializer ; CHECK-NEXT: ret <3 x i1> [[R]] ; %t0 = shl <3 x i8> , %bits @@ -57,9 +54,8 @@ define <3 x i1> @p2_vec_undef1(<3 x i8> %val, <3 x i8> %bits) { ; CHECK-LABEL: @p2_vec_undef1( -; CHECK-NEXT: [[T0:%.*]] = shl <3 x i8> , [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor <3 x i8> [[T0]], -; CHECK-NEXT: [[R:%.*]] = icmp uge <3 x i8> [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr <3 x i8> [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp eq <3 x i8> [[VAL_HIGHBITS]], zeroinitializer ; CHECK-NEXT: ret <3 x i1> [[R]] ; %t0 = shl <3 x i8> , %bits @@ -70,9 +66,8 @@ define <3 x i1> @p2_vec_undef2(<3 x i8> %val, <3 x i8> %bits) { ; CHECK-LABEL: @p2_vec_undef2( -; CHECK-NEXT: [[T0:%.*]] = shl <3 x i8> , [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor <3 x i8> [[T0]], -; CHECK-NEXT: [[R:%.*]] = icmp uge <3 x i8> [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr <3 x i8> [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp eq <3 x i8> [[VAL_HIGHBITS]], zeroinitializer ; CHECK-NEXT: ret <3 x i1> [[R]] ; %t0 = shl <3 x i8> , %bits @@ -89,10 +84,9 @@ define i1 @c0(i8 %bits) { ; CHECK-LABEL: @c0( -; CHECK-NEXT: [[T0:%.*]] = shl i8 -1, [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor i8 [[T0]], -1 ; CHECK-NEXT: [[VAL:%.*]] = call i8 @gen8() -; CHECK-NEXT: [[R:%.*]] = icmp ule i8 [[VAL]], [[T1]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr i8 [[VAL]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[VAL_HIGHBITS]], 0 ; CHECK-NEXT: ret i1 [[R]] ; %t0 = shl i8 -1, %bits @@ -112,8 +106,8 @@ ; CHECK-LABEL: @oneuse0( ; CHECK-NEXT: [[T0:%.*]] = shl i8 -1, [[BITS:%.*]] ; CHECK-NEXT: call void @use8(i8 [[T0]]) -; CHECK-NEXT: [[T1:%.*]] = xor i8 [[T0]], -1 -; CHECK-NEXT: [[R:%.*]] = icmp uge i8 [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr i8 [[VAL:%.*]], [[BITS]] +; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[VAL_HIGHBITS]], 0 ; CHECK-NEXT: ret i1 [[R]] ; %t0 = shl i8 -1, %bits Index: test/Transforms/InstCombine/icmp-ult-of-not-of-shl-allones-by-bits-and-val-to-icmp-ne-of-lshr-val-by-bits-and-0.ll =================================================================== --- test/Transforms/InstCombine/icmp-ult-of-not-of-shl-allones-by-bits-and-val-to-icmp-ne-of-lshr-val-by-bits-and-0.ll +++ test/Transforms/InstCombine/icmp-ult-of-not-of-shl-allones-by-bits-and-val-to-icmp-ne-of-lshr-val-by-bits-and-0.ll @@ -14,9 +14,8 @@ define i1 @p0(i8 %val, i8 %bits) { ; CHECK-LABEL: @p0( -; CHECK-NEXT: [[T0:%.*]] = shl i8 -1, [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor i8 [[T0]], -1 -; CHECK-NEXT: [[R:%.*]] = icmp ult i8 [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr i8 [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[VAL_HIGHBITS]], 0 ; CHECK-NEXT: ret i1 [[R]] ; %t0 = shl i8 -1, %bits @@ -31,9 +30,8 @@ define <2 x i1> @p1_vec(<2 x i8> %val, <2 x i8> %bits) { ; CHECK-LABEL: @p1_vec( -; CHECK-NEXT: [[T0:%.*]] = shl <2 x i8> , [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor <2 x i8> [[T0]], -; CHECK-NEXT: [[R:%.*]] = icmp ult <2 x i8> [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr <2 x i8> [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp ne <2 x i8> [[VAL_HIGHBITS]], zeroinitializer ; CHECK-NEXT: ret <2 x i1> [[R]] ; %t0 = shl <2 x i8> , %bits @@ -44,9 +42,8 @@ define <3 x i1> @p2_vec_undef0(<3 x i8> %val, <3 x i8> %bits) { ; CHECK-LABEL: @p2_vec_undef0( -; CHECK-NEXT: [[T0:%.*]] = shl <3 x i8> , [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor <3 x i8> [[T0]], -; CHECK-NEXT: [[R:%.*]] = icmp ult <3 x i8> [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr <3 x i8> [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp ne <3 x i8> [[VAL_HIGHBITS]], zeroinitializer ; CHECK-NEXT: ret <3 x i1> [[R]] ; %t0 = shl <3 x i8> , %bits @@ -57,9 +54,8 @@ define <3 x i1> @p2_vec_undef1(<3 x i8> %val, <3 x i8> %bits) { ; CHECK-LABEL: @p2_vec_undef1( -; CHECK-NEXT: [[T0:%.*]] = shl <3 x i8> , [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor <3 x i8> [[T0]], -; CHECK-NEXT: [[R:%.*]] = icmp ult <3 x i8> [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr <3 x i8> [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp ne <3 x i8> [[VAL_HIGHBITS]], zeroinitializer ; CHECK-NEXT: ret <3 x i1> [[R]] ; %t0 = shl <3 x i8> , %bits @@ -70,9 +66,8 @@ define <3 x i1> @p2_vec_undef2(<3 x i8> %val, <3 x i8> %bits) { ; CHECK-LABEL: @p2_vec_undef2( -; CHECK-NEXT: [[T0:%.*]] = shl <3 x i8> , [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor <3 x i8> [[T0]], -; CHECK-NEXT: [[R:%.*]] = icmp ult <3 x i8> [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr <3 x i8> [[VAL:%.*]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp ne <3 x i8> [[VAL_HIGHBITS]], zeroinitializer ; CHECK-NEXT: ret <3 x i1> [[R]] ; %t0 = shl <3 x i8> , %bits @@ -89,10 +84,9 @@ define i1 @c0(i8 %bits) { ; CHECK-LABEL: @c0( -; CHECK-NEXT: [[T0:%.*]] = shl i8 -1, [[BITS:%.*]] -; CHECK-NEXT: [[T1:%.*]] = xor i8 [[T0]], -1 ; CHECK-NEXT: [[VAL:%.*]] = call i8 @gen8() -; CHECK-NEXT: [[R:%.*]] = icmp ugt i8 [[VAL]], [[T1]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr i8 [[VAL]], [[BITS:%.*]] +; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[VAL_HIGHBITS]], 0 ; CHECK-NEXT: ret i1 [[R]] ; %t0 = shl i8 -1, %bits @@ -112,8 +106,8 @@ ; CHECK-LABEL: @oneuse0( ; CHECK-NEXT: [[T0:%.*]] = shl i8 -1, [[BITS:%.*]] ; CHECK-NEXT: call void @use8(i8 [[T0]]) -; CHECK-NEXT: [[T1:%.*]] = xor i8 [[T0]], -1 -; CHECK-NEXT: [[R:%.*]] = icmp ult i8 [[T1]], [[VAL:%.*]] +; CHECK-NEXT: [[VAL_HIGHBITS:%.*]] = lshr i8 [[VAL:%.*]], [[BITS]] +; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[VAL_HIGHBITS]], 0 ; CHECK-NEXT: ret i1 [[R]] ; %t0 = shl i8 -1, %bits