[llvm] [GlobalISel] emit G_BITCAST in widenScalarMergeValues when DstTy does not match WideTy (PR #203014)

[Matt Arsenault via llvm-commits]

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@@ -1897,6 +1897,86 @@ TEST_F(AArch64GISelMITest, WidenScalarMergeValuesPointer) {
   EXPECT_TRUE(CheckMachineFunction(*MF, CheckStr)) << *MF;
 }
 
+TEST_F(AArch64GISelMITest, WidenScalarMergeValuesFloat) {
+  setUp();
+  if (!TM)
+    GTEST_SKIP();
+
+  constexpr ElementCount EC0 = ElementCount::getFixed(0);
+  const LLT I8 = LLT(LLT::Kind::INTEGER, EC0, 8);
+  const LLT I16 = LLT(LLT::Kind::INTEGER, EC0, 16);
+  const LLT F16 = LLT::float16();
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arsenm wrote:

Use normal LLT::integer(Size) constructor? Plus I'm surprised fixed size of 0 doesn't assert 

https://github.com/llvm/llvm-project/pull/203014