[GlobalISel][Legalizer] Fix minScalarEltSameAsIf to handle p0 element types.

The mutation the action generates tries to change the input type into the
element type of larger vector type. This doesn't work if the larger element
type is a vector of pointers since it creates an illegal mutation between
scalar and pointer types.

Differential Revision: https://reviews.llvm.org/D133671

diff --git a/llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h b/llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
index c0cad8f..090388d 100644 (file)
--- a/llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
@@ -1040,6 +1040,8 @@ public:
         },
         [=](const LegalityQuery &Query) {
           LLT T = Query.Types[LargeTypeIdx];
+          if (T.isVector() && T.getElementType().isPointer())
+            T = T.changeElementType(LLT::scalar(T.getScalarSizeInBits()));
           return std::make_pair(TypeIdx, T);
         });
   }

diff --git a/llvm/unittests/CodeGen/GlobalISel/LegalizerInfoTest.cpp b/llvm/unittests/CodeGen/GlobalISel/LegalizerInfoTest.cpp
index 0cce674..5ff5a07 100644 (file)
--- a/llvm/unittests/CodeGen/GlobalISel/LegalizerInfoTest.cpp
+++ b/llvm/unittests/CodeGen/GlobalISel/LegalizerInfoTest.cpp
@@ -241,6 +241,7 @@ TEST(LegalizerInfoTest, RuleSets) {
   const LLT v2s64 = LLT::fixed_vector(2, 64);
 
   const LLT p0 = LLT::pointer(0, 32);
+  const LLT v2p0 = LLT::fixed_vector(2, p0);
   const LLT v3p0 = LLT::fixed_vector(3, p0);
   const LLT v4p0 = LLT::fixed_vector(4, p0);
 
@@ -427,6 +428,21 @@ TEST(LegalizerInfoTest, RuleSets) {
     EXPECT_ACTION(FewerElements, 0, s16,
                   LegalityQuery(G_ADD, {LLT::scalable_vector(8, 16)}));
   }
+
+  // Test minScalarEltSameAsIf
+  {
+    LegalizerInfo LI;
+    auto &LegacyInfo = LI.getLegacyLegalizerInfo();
+
+    LI.getActionDefinitionsBuilder(G_SELECT).minScalarEltSameAsIf(
+        all(isVector(0), isVector(1)), 1, 0);
+    LegacyInfo.computeTables();
+    LLT p1 = LLT::pointer(1, 32);
+    LLT v2p1 = LLT::fixed_vector(2, p1);
+
+    EXPECT_ACTION(WidenScalar, 1, v2s32, LegalityQuery(G_SELECT, {v2p0, v2s1}));
+    EXPECT_ACTION(WidenScalar, 1, v2s32, LegalityQuery(G_SELECT, {v2p1, v2s1}));
+  }
 }
 
 TEST(LegalizerInfoTest, MMOAlignment) {