[clang] [llvm] [Hexagon] Allow reservation of caller saved registers via -ffixed-rXX (PR #205733)

[Abinaya Saravanan via cfe-commits]

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@@ -7041,6 +7041,9 @@ def mhexagon_hvx_ieee_fp : Flag<["-"], "mhvx-ieee-fp">,
 def mno_hexagon_hvx_ieee_fp : Flag<["-"], "mno-hvx-ieee-fp">,
   Group<m_hexagon_Features_Group>,
   HelpText<"Disable Hexagon HVX IEEE floating-point">;
+foreach i = {6-7} in
+    def ffixed_r#i : Flag<["-"], "ffixed-r"#i>, Group<f_Group>,
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quic-asaravan wrote:

f_Group stands for "target-independent" options (definition at the beginning of the file). m_Group is for specifying "target-dependent" options which would be more appropriate for Hexagon options and consistent. Any reason why this went into f_Group?

https://github.com/llvm/llvm-project/pull/205733