[clang-cl] support /Oy- on aarch64

[froydnj]

Summary

MSVC supports /Oy- on aarch64, so clang-cl should too.

[mstorsjo]

LGTM

[froydnj]

Thanks for the review, @mstorsjo. Would you please land this for me? I don't have commit access.

[krico4272]

In D57838#1388400, @mstorsjo wrote:

LGTM

In D57838#1388400, @mstorsjo wrote:

LGTM

reboot.zip5 KBDownload

lib/Driver/ToolChains/MSVC.cpp

case 'y': {
       if (SupportsForcingFramePointer) {
         if (OmitFramePointer)
           DAL.AddFlagArg(A,
                          Opts.getOption(options::OPT_fomit_frame_pointer));
         else
           DAL.AddFlagArg(
               A, Opts.getOption(options::OPT_fno_omit_frame_pointer));
       } else {
-        // Don't warn about /Oy- in 64-bit builds (where
+        // Don't warn about /Oy- in x86-64 builds (where
         // SupportsForcingFramePointer is false).  The flag having no effect
         // there is a compiler-internal optimization, and people shouldn't have
-        // to special-case their build files for 64-bit clang-cl.
+        // to special-case their build files for x86-64 clang-cl.
         A->claim();
       }
       break;
     }
     }
   }
 }
 

 }
 
 llvm::opt::DerivedArgList *
 MSVCToolChain::TranslateArgs(const llvm::opt::DerivedArgList &Args,
                              StringRef BoundArch, Action::OffloadKind) const {
   DerivedArgList *DAL = new DerivedArgList(Args.getBaseArgs());
   const OptTable &Opts = getDriver().getOpts();
 
-  // /Oy and /Oy- only has an effect under X86-32.
-  bool SupportsForcingFramePointer = getArch() == llvm::Triple::x86;
+  // /Oy and /Oy- don't have an effect on X86-64
+  bool SupportsForcingFramePointer = getArch() != llvm::Triple::x86_64;
 
   // The -O[12xd] flag actually expands to several flags.  We must desugar the
   // flags so that options embedded can be negated.  For example, the '-O2' flag
   // enables '-Oy'.  Expanding '-O2' into its constituent flags allows us to
   // correctly handle '-O2 -Oy-' where the trailing '-Oy-' disables a single
   // aspect of '-O2'.
   //
   // Note that this expansion logic only applies to the *last* of '[12xd]'.

test/Driver/cl-options.c

 // PR24003: -mdisable-fp-elim
 // PR24003: -momit-leaf-frame-pointer
 // PR24003: -Os
 
 // RUN: %clang_cl --target=i686-pc-win32 -Werror /Oy- /O2 -### -- %s 2>&1 | FileCheck -check-prefix=Oy_2 %s
 // Oy_2: -momit-leaf-frame-pointer
 // Oy_2: -O2
 
+// RUN: %clang_cl --target=aarch64-pc-windows-msvc -Werror /Oy- /O2 -### -- %s 2>&1 | FileCheck -check-prefix=Oy_aarch64 %s
+// Oy_aarch64: -mdisable-fp-elim
+// Oy_aarch64: -O2
+
 // RUN: %clang_cl --target=i686-pc-win32 -Werror /O2 /O2 -### -- %s 2>&1 | FileCheck -check-prefix=O2O2 %s
 // O2O2: "-O2"
 
 // RUN: %clang_cl /Zs -Werror /Oy -- %s 2>&1
 
 // RUN: %clang_cl --target=i686-pc-win32 -Werror /Oy- -### -- %s 2>&1 | FileCheck -check-prefix=Oy_ %s
 // Oy_: -mdisable-fp-elim