[llvm] [PreISelIntrinsicLowering] Zext/trunc count parameter as necessary for memset_pattern16 emission (PR #129239)

[Nikita Popov via llvm-commits]

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@@ -394,11 +394,12 @@ bool PreISelIntrinsicLowering::expandMemIntrinsicUses(Function &F) const {
       Module *M = Memset->getModule();
       const DataLayout &DL = Memset->getDataLayout();
 
+      Type *DestPtrTy = Memset->getRawDest()->getType();
+      Type *IntIdxTy = DL.getIndexType(DestPtrTy);
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nikic wrote:

As we're emitting a libcall here, it would be preferable to use TLI.getSizeTType() instead. Can also use the getAsSizeT helper for the ConstantInt below.

It will ultimately produce the same type, but this way we're not baking in new assumptions.

https://github.com/llvm/llvm-project/pull/129239