[flang] Correctly handle -mframe-pointer=reserved (#146937)

Fixes `#146802`

#146582 started using the `Reserved` Frame Pointer kind for Arm64
Windows, but this revealed a bug in Flang where it copied the
`-mframe-pointer=reserved` flag from Clang, but didn't correctly handle
it in its own command line parser and subsequent compilation pipeline.

This change adds support for `-mframe-pointer=reserved` and adds a test
to make sure that functions are correctly marked when the flag is set.

1 files changed, 2 insertions, 1 deletions

diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index 8e4c210..e5c6b1d 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -291,13 +291,14 @@ static void parseCodeGenArgs(Fortran::frontend::CodeGenOptions &opts,
 
   opts.AliasAnalysis = opts.OptimizationLevel > 0;
 
-  // -mframe-pointer=none/non-leaf/all option.
+  // -mframe-pointer=none/non-leaf/reserved/all option.
   if (const llvm::opt::Arg *a =
           args.getLastArg(clang::driver::options::OPT_mframe_pointer_EQ)) {
     std::optional<llvm::FramePointerKind> val =
         llvm::StringSwitch<std::optional<llvm::FramePointerKind>>(a->getValue())
             .Case("none", llvm::FramePointerKind::None)
             .Case("non-leaf", llvm::FramePointerKind::NonLeaf)
+            .Case("reserved", llvm::FramePointerKind::Reserved)
             .Case("all", llvm::FramePointerKind::All)
             .Default(std::nullopt);