[PATCH] D84043: [AArch64][SVE] Fix CFA calculation in presence of SVE objects.

Tue Aug 4 10:50:52 PDT 2020

rupprecht added inline comments.

================
Comment at: llvm/lib/Target/AArch64/AArch64FrameLowering.cpp:443-445
+  // Build up the expression (SP + NumBytes + NumVGScaledBytes * AArch64::VG)
+  SmallString<64> Expr;
+  Expr.push_back(dwarf::DW_OP_breg0 + /*SP*/ 31);
----------------
rupprecht wrote:
> sdesmalen wrote:
> > rupprecht wrote:
> > > I'm seeing the following warning here:
> > > 
> > > ```
> > > [723/2438] Building CXX object lib/Target/AArch64/CMakeFiles/LLVMAArch64CodeGen.dir/AArch64FrameLowering.cpp.o
> > > /home/rupprecht/src/llvm-project/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp:445:37: warning: implicit conversion from 'int' to 'const char' changes value from 143 to -113 [-Wconstant-conversion]
> > >   Expr.push_back(dwarf::DW_OP_breg0 + /*SP*/ 31);
> > >        ~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~
> > > 1 warning generated.
> > > ```
> > > 
> > > Do you see it as well? Is there a way to silence it?
> > Sorry, I don't see this warning. What compiler are you using?
> A recent-ish bootstrapped clang from June 7:
> 
> `clang++ --version ` => `clang version 11.0.0 (https://github.com/llvm/llvm-project.git ec04ce4623522a326672f03fecb41812386a8c0e)`
> 
> I'll see if the issue goes away when rolling up to a newer clang
No, still present:

```
$ clang++ --version
clang version 12.0.0 (https://github.com/llvm/llvm-project.git b7cfa6ca92830b3c331cb44706bb279996663439)
```

... and, looks like @dblaikie just fixed this in e31cfc4cd3e393300002e9c519787c96e3b67bab.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D84043/new/

https://reviews.llvm.org/D84043