[llvm] [VPlan] Add WidenGEP::getSourceElementType (NFC) (PR #159029)

[Ramkumar Ramachandra via llvm-commits]

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@@ -1763,6 +1763,8 @@ struct LLVM_ABI_FOR_TEST VPWidenSelectRecipe : public VPRecipeWithIRFlags,
 
 /// A recipe for handling GEP instructions.
 class LLVM_ABI_FOR_TEST VPWidenGEPRecipe : public VPRecipeWithIRFlags {
+  Type *SourceElementTy;
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artagnon wrote:

I think there's a general effort to avoid using getUnderlyingValue(): for example, we store opcode and operands even when it can be found in the underlying instr.

https://github.com/llvm/llvm-project/pull/159029