[PATCH] D88594: [OpenMP] Add Error Handling for Conflicting Pointer Sizes for Target Offload

[Joseph Huber via Phabricator via cfe-commits]

jhuber6 added inline comments.


================
Comment at: clang/lib/Frontend/CompilerInvocation.cpp:3209-3214
+      else if ((T.isArch64Bit() && TT.isArch32Bit()) ||
+               (T.isArch64Bit() && TT.isArch16Bit()) ||
+               (T.isArch32Bit() && TT.isArch64Bit()) ||
+               (T.isArch32Bit() && TT.isArch16Bit()) ||
+               (T.isArch16Bit() && TT.isArch32Bit()) ||
+               (T.isArch16Bit() && TT.isArch64Bit()))
----------------
ABataev wrote:
> jhuber6 wrote:
> > ABataev wrote:
> > > jhuber6 wrote:
> > > > ABataev wrote:
> > > > > Maybe do something like `Triple::getArchPointerBitWidth(T.getArch()) != Triple::getArchPointerBitWidth(TT.getArch())"?
> > > > That was my first thought but that function is private to the Triple class so I just went with this brute force method. The file has this comment for the justification.
> > > > 
> > > > 
> > > > ```
> > > >    /// Test whether the architecture is 64-bit
> > > >    ///
> > > >    /// Note that this tests for 64-bit pointer width, and nothing else. Note
> > > >    /// that we intentionally expose only three predicates, 64-bit, 32-bit, and
> > > >    /// 16-bit. The inner details of pointer width for particular architectures
> > > >    /// is not summed up in the triple, and so only a coarse grained predicate
> > > >    /// system is provided.
> > > > ```
> > > Would it be better to convert the results of `isArch...Bit()` to enum and compare enums then? Like:
> > > ```
> > > enum {Arch16bit, Arch32bit, Arch64bit} TArch, TTArch;
> > > 
> > > if (T.isArch16Bit())
> > >   Tarch = Arch16Bit;
> > > else if ...
> > > ...
> > > // Same for TT.
> > > if (TArch != TTArch)
> > > ...
> > > ```
> > You'd end up with a similar situation right, having about 6 conditionals manually checking check predicate right?
> > 
> > ```
> > if (T.isArch16Bit())
> > else if (T.isArch32Bit())
> > else if (T.isArch64Bit())
> > if (TT.isArch16Bit())
> > else if (TT.isArch32Bit())
> > else if (TT.isArch64Bit())
> > ```
> Yes, but it may be easier to maintain in the future, say when 128 or 256 bits architectures are added? :)
> Plus, the last one should not be `else if`, just:
> ```
> else {
>   assert(T.isArch64Bit() && "Expected 64 bits arch");
>   TArch = ...;
> }
> ```
Something like this sufficient?
```
  enum ArchPtrSize {Arch16Bit, Arch16Bit, Arch16Bit};
  auto GetArchPtrSize[](llvm::Triple &T) {
      if (T.isArch16Bit())
          return Arch16Bit;
      else if (T.isArch32Bit())
          return Arch32Bit;
      else
          return Arch64Bit;
  };

  if (GetArchPtrSize(T) != GetArchPtrSize(TT)) { ... }

```


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D88594/new/

https://reviews.llvm.org/D88594