[llvm] [SandboxIR][NFC] Factor out common test for CastInst subclasses (PR #101410)

[Arthur Eubanks via llvm-commits]

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@@ -34,6 +34,8 @@ struct SandboxIRTest : public testing::Test {
         return &BB;
     llvm_unreachable("Expected to find basic block!");
   }
+  template <typename SubclassT, sandboxir::Instruction::Opcode OpcodeT>
+  void testCastInst(const char *IRToParse, Type *SrcTy, Type *DstTy);
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aeubanks wrote:

usually templated definitions are inline rather than defined elsewhere from the declaration due to easily running into cases where you accidentally don't instantiate the definition

I kinda like making this a top level static template function and shuffling around some parameters (e.g. separating the `parseIR` and `testCastInst`, passing `M` to `testCastInst`), but up to you

https://github.com/llvm/llvm-project/pull/101410