[PATCH] D110585: [Analysis][SimplifyLibCalls] Refactor code related to size_t in lib func signatures. NFCI

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


================
Comment at: llvm/lib/Analysis/TargetLibraryInfo.cpp:755
     --NumParams;
-    if (!IsSizeTTy(FTy.getParamType(NumParams)))
+    if (!FTy.getParamType(NumParams)->isIntegerTy(SizeTBits))
       return false;
----------------
arichardson wrote:
> nikic wrote:
> > I'd suggest to land these changes as an NFC refactoring -- just determine `SizeTBits` as `DL.getPointerSizeInBits()` for now.
> That would be incorrect for CHERI (well if we hardcode AS0 it will happen to work since we keep AS0 as 64-bit integer pointers and use AS200 for capabilities).
> It should IMO be `DL.getIndexSizeInBits(DL.getAllocaAddrSpace())` (or `getDefaultGlobalsAddressSpace()`) since that gives you `ptrdiff_t` which *should* be compatible with size_t.
> 
> One problem we have here is that there is no "libfunc address space" so there is no easy way to determine the expected address space for libfuncs without a pointer argument, etc. Should it be alloca/globals/something new?
> 
To be clear, I agree that this is incorrect, but that would be an NFC refactoring of the existing logic, so we can land the mass refactoring separately from the logic change.


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  https://reviews.llvm.org/D110585/new/

https://reviews.llvm.org/D110585