[llvm] r310063 - [InstCombine] Remove the (not (sext)) case from foldBoolSextMaskToSelect and inline the remaining code to match visitOr

[Craig Topper via llvm-commits]

Author: ctopper
Date: Fri Aug  4 09:07:20 2017
New Revision: 310063

URL: http://llvm.org/viewvc/llvm-project?rev=310063&view=rev
Log:
[InstCombine] Remove the (not (sext)) case from foldBoolSextMaskToSelect and inline the remaining code to match visitOr

Summary:
The (not (sext)) case is really (xor (sext), -1) which should have been simplified to (sext (xor, 1)) before we got here. So we shouldn't need to handle it.

With that taken care of we only need to two cases so don't need the swap anymore. This makes us in sync with the equivalent code in visitOr so inline this to match.

Reviewers: spatel, eli.friedman, majnemer

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36240

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
    llvm/trunk/test/Transforms/InstCombine/vector-casts.ll

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp?rev=310063&r1=310062&r2=310063&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp Fri Aug  4 09:07:20 2017
@@ -1188,31 +1188,6 @@ Instruction *InstCombiner::foldCastedBit
   return nullptr;
 }
 
-static Instruction *foldBoolSextMaskToSelect(BinaryOperator &I) {
-  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
-
-  // Canonicalize SExt or Not to the LHS
-  if (match(Op1, m_SExt(m_Value())) || match(Op1, m_Not(m_Value()))) {
-    std::swap(Op0, Op1);
-  }
-
-  // Fold (and (sext bool to A), B) --> (select bool, B, 0)
-  Value *X = nullptr;
-  if (match(Op0, m_SExt(m_Value(X))) && X->getType()->isIntOrIntVectorTy(1)) {
-    Value *Zero = Constant::getNullValue(Op1->getType());
-    return SelectInst::Create(X, Op1, Zero);
-  }
-
-  // Fold (and ~(sext bool to A), B) --> (select bool, 0, B)
-  if (match(Op0, m_Not(m_SExt(m_Value(X)))) &&
-      X->getType()->isIntOrIntVectorTy(1)) {
-    Value *Zero = Constant::getNullValue(Op0->getType());
-    return SelectInst::Create(X, Zero, Op1);
-  }
-
-  return nullptr;
-}
-
 static Instruction *foldAndToXor(BinaryOperator &I,
                                  InstCombiner::BuilderTy &Builder) {
   assert(I.getOpcode() == Instruction::And);
@@ -1480,8 +1455,14 @@ Instruction *InstCombiner::visitAnd(Bina
   if (Instruction *CastedAnd = foldCastedBitwiseLogic(I))
     return CastedAnd;
 
-  if (Instruction *Select = foldBoolSextMaskToSelect(I))
-    return Select;
+  // and(sext(A), B) / and(B, sext(A)) --> A ? B : 0, where A is i1 or <N x i1>.
+  Value *A;
+  if (match(Op0, m_OneUse(m_SExt(m_Value(A)))) &&
+      A->getType()->isIntOrIntVectorTy(1))
+    return SelectInst::Create(A, Op1, Constant::getNullValue(I.getType()));
+  if (match(Op1, m_OneUse(m_SExt(m_Value(A)))) &&
+      A->getType()->isIntOrIntVectorTy(1))
+    return SelectInst::Create(A, Op0, Constant::getNullValue(I.getType()));
 
   return Changed ? &I : nullptr;
 }

Modified: llvm/trunk/test/Transforms/InstCombine/vector-casts.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/vector-casts.ll?rev=310063&r1=310062&r2=310063&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/vector-casts.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/vector-casts.ll Fri Aug  4 09:07:20 2017
@@ -61,7 +61,7 @@ define <2 x i64> @test5(<4 x float> %a,
 ; CHECK-LABEL: @test5(
 ; CHECK-NEXT:    [[CMP:%.*]] = fcmp ult <4 x float> %a, zeroinitializer
 ; CHECK-NEXT:    [[CMP4:%.*]] = fcmp ult <4 x float> %b, zeroinitializer
-; CHECK-NEXT:    [[NARROW:%.*]] = and <4 x i1> [[CMP4]], [[CMP]]
+; CHECK-NEXT:    [[NARROW:%.*]] = and <4 x i1> [[CMP]], [[CMP4]]
 ; CHECK-NEXT:    [[AND:%.*]] = sext <4 x i1> [[NARROW]] to <4 x i32>
 ; CHECK-NEXT:    [[CONV:%.*]] = bitcast <4 x i32> [[AND]] to <2 x i64>
 ; CHECK-NEXT:    ret <2 x i64> [[CONV]]