[PATCH] D66827: Add support for MS qualifiers __ptr32, __ptr64, __sptr, __uptr.

[Amy Huang via Phabricator via llvm-commits]

akhuang marked 2 inline comments as done.
akhuang added inline comments.


================
Comment at: clang/lib/AST/MicrosoftMangle.cpp:1874
+    case LangAS::ptr32_sptr:
+      Extra.mangleSourceName("_ASPtr32_sptr");
+      break;
----------------
rnk wrote:
> Hm, we should actually mangle these as they do. See the FIXME comment above the definition of `PointersAre64Bit`. If you look at the uses of PointersAre64Bit, you should be able to find the places where you need to check if a pointer type is either in the explicit 64-bit address space or in the default address space for a 64-bit target. That check sounds like a good helper function.
Added a function to check for 64-bit address space / default 64-bit pointer. I also changed it so that the pointer size address spaces mangle as normal types and not address space types. 


================
Comment at: clang/lib/Sema/SemaOverload.cpp:2874
                              N->getUnqualifiedType())) {
+      const PointerType *OldTypePtr =
+          dyn_cast<PointerType>(O->getUnqualifiedType());
----------------
rnk wrote:
> This probably deserves a comment. It looks like this lets you do this:
> ```
> void foo(int *__ptr64);
> void foo(int *p) { } // assume x64 target
> ```
> ... without having the compiler think it's creating an overload.
> 
> Separately, MSVC doesn't permit `__ptr32/__ptr64` overloads. Is it possible to implement that here as well?
Comment added. 

Although I think that for 
```
void foo(int *__ptr64);
void foo(int *p) { } // assume x64 target
```
this code doesn't affect the overload because `int * __ptr64` and `int *` are already the same type?

As far as I can tell this also doesn't allow `__ptr32/__ptr64` overloads, because it counts them as the same type. It gives a "conflicting types" error instead of a "redefintion" error though, so I'll look into that. 


================
Comment at: llvm/test/CodeGen/X86/mixed-ptr-sizes.ll:11
+;   f->p64 = i;
+;   use_foo(f);
+; }
----------------
rnk wrote:
> Do you need use_foo? I think `f` is a parameter, so the compiler can't remove any stores to it, even without a call to use it. You should be able to simplify the test to skip these calls.
Deleted `use_foo`, thanks.


================
Comment at: llvm/test/CodeGen/X86/mixed-ptr-sizes.ll:30
+;
+; $ clang -cc1 -triple x86_64-windows-msvc -fms-extensions -O2 -S t.cpp
+
----------------
rnk wrote:
> If you compile this code as plain C code, then it won't have as much name mangling, which makes the .ll file more readable.
done


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D66827/new/

https://reviews.llvm.org/D66827