diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp index 7fd91c72a2fb0..c58a63483a717 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp @@ -2823,9 +2823,9 @@ static Instruction *foldSelectWithSRem(SelectInst &SI, InstCombinerImpl &IC, // %cnd = icmp slt i32 %rem, 0 // %add = add i32 %rem, %n // %sel = select i1 %cnd, i32 %add, i32 %rem - if (match(TrueVal, m_Add(m_Specific(RemRes), m_Value(Remainder))) && + if (match(TrueVal, m_c_Add(m_Specific(RemRes), m_Value(Remainder))) && match(RemRes, m_SRem(m_Value(Op), m_Specific(Remainder))) && - IC.isKnownToBeAPowerOfTwo(Remainder, /*OrZero*/ true) && + IC.isKnownToBeAPowerOfTwo(Remainder, /*OrZero=*/true) && FalseVal == RemRes) return FoldToBitwiseAnd(Remainder); diff --git a/llvm/test/Transforms/InstCombine/select-divrem.ll b/llvm/test/Transforms/InstCombine/select-divrem.ll index a674f9c64b200..7dff78e3057e2 100644 --- a/llvm/test/Transforms/InstCombine/select-divrem.ll +++ b/llvm/test/Transforms/InstCombine/select-divrem.ll @@ -322,6 +322,21 @@ define i8 @rem_euclid_non_const_pow2(i8 %0, i8 %1) { ret i8 %sel } +define i8 @rem_euclid_non_const_pow2_commuted(i8 %0, i8 %1) { +; CHECK-LABEL: @rem_euclid_non_const_pow2_commuted( +; CHECK-NEXT: [[NOTMASK:%.*]] = shl nsw i8 -1, [[TMP0:%.*]] +; CHECK-NEXT: [[TMP3:%.*]] = xor i8 [[NOTMASK]], -1 +; CHECK-NEXT: [[SEL:%.*]] = and i8 [[TMP1:%.*]], [[TMP3]] +; CHECK-NEXT: ret i8 [[SEL]] +; + %pow2 = shl i8 1, %0 + %rem = srem i8 %1, %pow2 + %cond = icmp slt i8 %rem, 0 + %add = add i8 %pow2, %rem + %sel = select i1 %cond, i8 %add, i8 %rem + ret i8 %sel +} + define i32 @rem_euclid_pow2_true_arm_folded(i32 %n) { ; CHECK-LABEL: @rem_euclid_pow2_true_arm_folded( ; CHECK-NEXT: [[RES:%.*]] = and i32 [[N:%.*]], 1