[Flang][Driver] Add support for fomit-frame-pointer 1/2

[victorkingi]

Summary

Mark the '-fomit-frame-pointer' as visible in the Flang Driver.

Note 1: This is just re-instating the previous behaviour that this flag is accepted by Flang but ignored.
Note 2: A subsequent patch will enable support for this flag in Flang by sharing code (after appropriate refactoring) with Clang.

[kiranchandramohan]

For our immediate purpose, I think changing the visibility in the Driver to include flang is sufficient. After that, we can spend time implementing this properly by refactoring the code to llvm.

llvm/include/llvm/Frontend/Driver/FramePointer.h

11 ↗

(On Diff #552322)

We should not include clang headers in llvm. We also should not refer to clang inside llvm.

[awarzynski]

Temporary fix for unknown argument error '-fomit-frame-pointer' when running flang tests

I don't follow - there's quite a lot going on here. More than the summary suggests.

[victorkingi]

In D158507#4606498, @awarzynski wrote:

Temporary fix for unknown argument error '-fomit-frame-pointer' when running flang tests

I don't follow - there's quite a lot going on here. More than the summary suggests.

Sorry about that, will be pushing a minimal version since what was needed for the fix was only an update to Options.td file

[victorkingi]

Minimalized patch to only have update to Options.td as well as
tests accompanying the change.

[victorkingi]

clang/include/clang/Driver/Options.td

7236–7240

This will be needed in the second patch when the flag functionality is added

[victorkingi]

This comment was removed by victorkingi.

[victorkingi]

revert addition of m64 visibility in Options.td

[victorkingi]

Removed mframe_pointer_eq update in Options.td, not required.

[victorkingi]

Moved function implementations from llvm directory to clang

clang/include/clang/Driver/Options.td

def fno_module_file_deps : Flag <["-"], "fno-module-file-deps">, Group<f_Group>,
   Flags<[NoXarchOption]>;
 def fno_ms_extensions : Flag<["-"], "fno-ms-extensions">, Group<f_Group>,
   Visibility<[ClangOption, CLOption]>;
 def fno_ms_compatibility : Flag<["-"], "fno-ms-compatibility">, Group<f_Group>,
   Visibility<[ClangOption, CLOption]>;
 def fno_objc_legacy_dispatch : Flag<["-"], "fno-objc-legacy-dispatch">, Group<f_Group>;
 def fno_objc_weak : Flag<["-"], "fno-objc-weak">, Group<f_Group>,
   Visibility<[ClangOption, CC1Option]>;
-def fno_omit_frame_pointer : Flag<["-"], "fno-omit-frame-pointer">, Group<f_Group>;
+def fno_omit_frame_pointer : Flag<["-"], "fno-omit-frame-pointer">, Group<f_Group>,
+  Visibility<[ClangOption, FlangOption]>;
 defm operator_names : BoolFOption<"operator-names",
   LangOpts<"CXXOperatorNames">, Default<cplusplus.KeyPath>,
   NegFlag<SetFalse, [], [ClangOption, CC1Option],
           "Do not treat C++ operator name keywords as synonyms for operators">,
   PosFlag<SetTrue>>;
 def fdiagnostics_absolute_paths : Flag<["-"], "fdiagnostics-absolute-paths">, Group<f_Group>,
   Visibility<[ClangOption, CC1Option, CLOption, DXCOption]>,
   HelpText<"Print absolute paths in diagnostics">,
def fobjc_disable_direct_methods_for_testing :
   MarshallingInfoFlag<LangOpts<"ObjCDisableDirectMethodsForTesting">>;
 defm objc_avoid_heapify_local_blocks : BoolFOption<"objc-avoid-heapify-local-blocks",
   CodeGenOpts<"ObjCAvoidHeapifyLocalBlocks">, DefaultFalse,
   PosFlag<SetTrue, [], [ClangOption], "Try">,
   NegFlag<SetFalse, [], [ClangOption], "Don't try">,
   BothFlags<[], [CC1Option], " to avoid heapifying local blocks">>;
 
 def fomit_frame_pointer : Flag<["-"], "fomit-frame-pointer">, Group<f_Group>,
+  Visibility<[ClangOption, FlangOption]>,
   HelpText<"Omit the frame pointer from functions that don't need it. "
   "Some stack unwinding cases, such as profilers and sanitizers, may prefer specifying -fno-omit-frame-pointer. "
   "On many targets, -O1 and higher omit the frame pointer by default. "
   "-m[no-]omit-leaf-frame-pointer takes precedence for leaf functions">;
 def fopenmp : Flag<["-"], "fopenmp">, Group<f_Group>,
   Flags<[NoArgumentUnused]>,
   Visibility<[ClangOption, CC1Option, FlangOption, FC1Option]>,
   HelpText<"Parse OpenMP pragmas and generate parallel code.">;

 def no_struct_path_tbaa : Flag<["-"], "no-struct-path-tbaa">,
   HelpText<"Turn off struct-path aware Type Based Alias Analysis">,
   MarshallingInfoNegativeFlag<CodeGenOpts<"StructPathTBAA">>;
 def new_struct_path_tbaa : Flag<["-"], "new-struct-path-tbaa">,
   HelpText<"Enable enhanced struct-path aware Type Based Alias Analysis">;
 def mdebug_pass : Separate<["-"], "mdebug-pass">,
   HelpText<"Enable additional debug output">,
   MarshallingInfoString<CodeGenOpts<"DebugPass">>;
-def mframe_pointer_EQ : Joined<["-"], "mframe-pointer=">,
-  HelpText<"Specify which frame pointers to retain.">, Values<"all,non-leaf,none">,
-  NormalizedValuesScope<"CodeGenOptions::FramePointerKind">, NormalizedValues<["All", "NonLeaf", "None"]>,
-  MarshallingInfoEnum<CodeGenOpts<"FramePointer">, "None">;
 def mabi_EQ_ieeelongdouble : Flag<["-"], "mabi=ieeelongdouble">,
   HelpText<"Use IEEE 754 quadruple-precision for long double">,
   MarshallingInfoFlag<LangOpts<"PPCIEEELongDouble">>;
 def mabi_EQ_vec_extabi : Flag<["-"], "mabi=vec-extabi">,
   HelpText<"Enable the extended Altivec ABI on AIX. Use volatile and nonvolatile vector registers">,
   MarshallingInfoFlag<LangOpts<"EnableAIXExtendedAltivecABI">>;
 def mfloat_abi : Separate<["-"], "mfloat-abi">,
   HelpText<"The float ABI to use">,

 
 def pic_level : Separate<["-"], "pic-level">,
   HelpText<"Value for __PIC__">,
   MarshallingInfoInt<LangOpts<"PICLevel">>;
 def pic_is_pie : Flag<["-"], "pic-is-pie">,
   HelpText<"File is for a position independent executable">,
   MarshallingInfoFlag<LangOpts<"PIE">>;
 
+def mframe_pointer_EQ : Joined<["-"], "mframe-pointer=">,
+  HelpText<"Specify which frame pointers to retain.">, Values<"all,non-leaf,none">,
+  NormalizedValuesScope<"CodeGenOptions::FramePointerKind">, NormalizedValues<["All", "NonLeaf", "None"]>,
+  MarshallingInfoEnum<CodeGenOpts<"FramePointer">, "None">;
+
 } // let Visibility = [CC1Option, FC1Option]
 
 let Visibility = [CC1Option] in {
 
 def fblocks_runtime_optional : Flag<["-"], "fblocks-runtime-optional">,
   HelpText<"Weakly link in the blocks runtime">,
   MarshallingInfoFlag<LangOpts<"BlocksRuntimeOptional">>;
 def fexternc_nounwind : Flag<["-"], "fexternc-nounwind">,

clang/lib/Driver/ToolChains/Clang.cpp

static bool ShouldEnableAutolink(const ArgList &Args, const ToolChain &TC,
   // The linker_option directives are intended for host compilation.
   if (JA.isDeviceOffloading(Action::OFK_Cuda) ||
       JA.isDeviceOffloading(Action::OFK_HIP))
     Default = false;
   return Args.hasFlag(options::OPT_fautolink, options::OPT_fno_autolink,
                       Default);
 }
 
-static bool mustUseNonLeafFramePointerForTarget(const llvm::Triple &Triple) {
-  switch (Triple.getArch()){
-  default:
-    return false;
-  case llvm::Triple::arm:
-  case llvm::Triple::thumb:
-    // ARM Darwin targets require a frame pointer to be always present to aid
-    // offline debugging via backtraces.
-    return Triple.isOSDarwin();
-  }
-}
-
-static bool useFramePointerForTargetByDefault(const ArgList &Args,
-                                              const llvm::Triple &Triple) {
-  if (Args.hasArg(options::OPT_pg) && !Args.hasArg(options::OPT_mfentry))
-    return true;
-
-  if (Triple.isAndroid()) {
-    switch (Triple.getArch()) {
-    case llvm::Triple::aarch64:
-    case llvm::Triple::arm:
-    case llvm::Triple::armeb:
-    case llvm::Triple::thumb:
-    case llvm::Triple::thumbeb:
-    case llvm::Triple::riscv64:
-      return true;
-    default:
-      break;
-    }
-  }
-
-  switch (Triple.getArch()) {
-  case llvm::Triple::xcore:
-  case llvm::Triple::wasm32:
-  case llvm::Triple::wasm64:
-  case llvm::Triple::msp430:
-    // XCore never wants frame pointers, regardless of OS.
-    // WebAssembly never wants frame pointers.
-    return false;
-  case llvm::Triple::ppc:
-  case llvm::Triple::ppcle:
-  case llvm::Triple::ppc64:
-  case llvm::Triple::ppc64le:
-  case llvm::Triple::riscv32:
-  case llvm::Triple::riscv64:
-  case llvm::Triple::sparc:
-  case llvm::Triple::sparcel:
-  case llvm::Triple::sparcv9:
-  case llvm::Triple::amdgcn:
-  case llvm::Triple::r600:
-  case llvm::Triple::csky:
-  case llvm::Triple::loongarch32:
-  case llvm::Triple::loongarch64:
-    return !areOptimizationsEnabled(Args);
-  default:
-    break;
-  }
-
-  if (Triple.isOSFuchsia() || Triple.isOSNetBSD()) {
-    return !areOptimizationsEnabled(Args);
-  }
-
-  if (Triple.isOSLinux() || Triple.getOS() == llvm::Triple::CloudABI ||
-      Triple.isOSHurd()) {
-    switch (Triple.getArch()) {
-    // Don't use a frame pointer on linux if optimizing for certain targets.
-    case llvm::Triple::arm:
-    case llvm::Triple::armeb:
-    case llvm::Triple::thumb:
-    case llvm::Triple::thumbeb:
-    case llvm::Triple::mips64:
-    case llvm::Triple::mips64el:
-    case llvm::Triple::mips:
-    case llvm::Triple::mipsel:
-    case llvm::Triple::systemz:
-    case llvm::Triple::x86:
-    case llvm::Triple::x86_64:
-      return !areOptimizationsEnabled(Args);
-    default:
-      return true;
-    }
-  }
-
-  if (Triple.isOSWindows()) {
-    switch (Triple.getArch()) {
-    case llvm::Triple::x86:
-      return !areOptimizationsEnabled(Args);
-    case llvm::Triple::x86_64:
-      return Triple.isOSBinFormatMachO();
-    case llvm::Triple::arm:
-    case llvm::Triple::thumb:
-      // Windows on ARM builds with FPO disabled to aid fast stack walking
-      return true;
-    default:
-      // All other supported Windows ISAs use xdata unwind information, so frame
-      // pointers are not generally useful.
-      return false;
-    }
-  }
-
-  return true;
-}
-
-static CodeGenOptions::FramePointerKind
-getFramePointerKind(const ArgList &Args, const llvm::Triple &Triple) {
-  // We have 4 states:
-  //
-  //  00) leaf retained, non-leaf retained
-  //  01) leaf retained, non-leaf omitted (this is invalid)
-  //  10) leaf omitted, non-leaf retained
-  //      (what -momit-leaf-frame-pointer was designed for)
-  //  11) leaf omitted, non-leaf omitted
-  //
-  //  "omit" options taking precedence over "no-omit" options is the only way
-  //  to make 3 valid states representable
-  Arg *A = Args.getLastArg(options::OPT_fomit_frame_pointer,
-                           options::OPT_fno_omit_frame_pointer);
-  bool OmitFP = A && A->getOption().matches(options::OPT_fomit_frame_pointer);
-  bool NoOmitFP =
-      A && A->getOption().matches(options::OPT_fno_omit_frame_pointer);
-  bool OmitLeafFP =
-      Args.hasFlag(options::OPT_momit_leaf_frame_pointer,
-                   options::OPT_mno_omit_leaf_frame_pointer,
-                   Triple.isAArch64() || Triple.isPS() || Triple.isVE() ||
-                   (Triple.isAndroid() && Triple.isRISCV64()));
-  if (NoOmitFP || mustUseNonLeafFramePointerForTarget(Triple) ||
-      (!OmitFP && useFramePointerForTargetByDefault(Args, Triple))) {
-    if (OmitLeafFP)
-      return CodeGenOptions::FramePointerKind::NonLeaf;
-    return CodeGenOptions::FramePointerKind::All;
-  }
-  return CodeGenOptions::FramePointerKind::None;
-}
-
 /// Add a CC1 option to specify the debug compilation directory.
 static const char *addDebugCompDirArg(const ArgList &Args,
                                       ArgStringList &CmdArgs,
                                       const llvm::vfs::FileSystem &VFS) {
   if (Arg *A = Args.getLastArg(options::OPT_ffile_compilation_dir_EQ,
                                options::OPT_fdebug_compilation_dir_EQ)) {
     if (A->getOption().matches(options::OPT_ffile_compilation_dir_EQ))
       CmdArgs.push_back(Args.MakeArgString(Twine("-fdebug-compilation-dir=") +
#endif
   if (Args.hasArg(options::OPT_fenable_matrix)) {
     // enable-matrix is needed by both the LangOpts and by LLVM.
     CmdArgs.push_back("-fenable-matrix");
     CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-enable-matrix");
   }
 
   CodeGenOptions::FramePointerKind FPKeepKind =
-                  getFramePointerKind(Args, RawTriple);
+
   const char *FPKeepKindStr = nullptr;
   switch (FPKeepKind) {
   case CodeGenOptions::FramePointerKind::None:
     FPKeepKindStr = "-mframe-pointer=none";
     break;
   case CodeGenOptions::FramePointerKind::NonLeaf:
     FPKeepKindStr = "-mframe-pointer=non-leaf";
     break;

clang/lib/Driver/ToolChains/CommonArgs.h

 //===--- CommonArgs.h - Args handling for multiple toolchains ---*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_COMMONARGS_H
 #define LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_COMMONARGS_H
 
+#include "clang/Basic/CodeGenOptions.h"
 #include "clang/Driver/Driver.h"
 #include "clang/Driver/InputInfo.h"
 #include "clang/Driver/Multilib.h"
 #include "clang/Driver/Tool.h"
 #include "clang/Driver/ToolChain.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"

 
 void addOpenMPDeviceRTL(const Driver &D, const llvm::opt::ArgList &DriverArgs,
                         llvm::opt::ArgStringList &CC1Args,
                         StringRef BitcodeSuffix, const llvm::Triple &Triple);
 } // end namespace tools
 } // end namespace driver
 } // end namespace clang
 
+clang::CodeGenOptions::FramePointerKind
+getFramePointerKind(const llvm::opt::ArgList &Args, const llvm::Triple &Triple);
+
 #endif // LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_COMMONARGS_H

clang/lib/Driver/ToolChains/CommonArgs.cpp

 #include "Arch/Sparc.h"
 #include "Arch/SystemZ.h"
 #include "Arch/VE.h"
 #include "Arch/X86.h"
 #include "HIPAMD.h"
 #include "Hexagon.h"
 #include "MSP430.h"
 #include "clang/Basic/CharInfo.h"
+#include "clang/Basic/CodeGenOptions.h"
 #include "clang/Basic/LangOptions.h"
 #include "clang/Basic/ObjCRuntime.h"
 #include "clang/Basic/Version.h"
 #include "clang/Config/config.h"
 #include "clang/Driver/Action.h"
 #include "clang/Driver/Compilation.h"
 #include "clang/Driver/Driver.h"
 #include "clang/Driver/DriverDiagnostic.h"

 #include "llvm/TargetParser/TargetParser.h"
 #include <optional>
 
 using namespace clang::driver;
 using namespace clang::driver::tools;
 using namespace clang;
 using namespace llvm::opt;
 
+static bool useFramePointerForTargetByDefault(const llvm::opt::ArgList &Args,
+                                              const llvm::Triple &Triple) {
+  if (Args.hasArg(clang::driver::options::OPT_pg) &&
+      !Args.hasArg(clang::driver::options::OPT_mfentry))
+    return true;
+
+  if (Triple.isAndroid()) {
+    switch (Triple.getArch()) {
+    case llvm::Triple::aarch64:
+    case llvm::Triple::arm:
+    case llvm::Triple::armeb:
+    case llvm::Triple::thumb:
+    case llvm::Triple::thumbeb:
+    case llvm::Triple::riscv64:
+      return true;
+    default:
+      break;
+    }
+  }
+
+  switch (Triple.getArch()) {
+  case llvm::Triple::xcore:
+  case llvm::Triple::wasm32:
+  case llvm::Triple::wasm64:
+  case llvm::Triple::msp430:
+    // XCore never wants frame pointers, regardless of OS.
+    // WebAssembly never wants frame pointers.
+    return false;
+  case llvm::Triple::ppc:
+  case llvm::Triple::ppcle:
+  case llvm::Triple::ppc64:
+  case llvm::Triple::ppc64le:
+  case llvm::Triple::riscv32:
+  case llvm::Triple::riscv64:
+  case llvm::Triple::sparc:
+  case llvm::Triple::sparcel:
+  case llvm::Triple::sparcv9:
+  case llvm::Triple::amdgcn:
+  case llvm::Triple::r600:
+  case llvm::Triple::csky:
+  case llvm::Triple::loongarch32:
+  case llvm::Triple::loongarch64:
+    return !clang::driver::tools::areOptimizationsEnabled(Args);
+  default:
+    break;
+  }
+
+  if (Triple.isOSFuchsia() || Triple.isOSNetBSD()) {
+    return !clang::driver::tools::areOptimizationsEnabled(Args);
+  }
+
+  if (Triple.isOSLinux() || Triple.getOS() == llvm::Triple::CloudABI ||
+      Triple.isOSHurd()) {
+    switch (Triple.getArch()) {
+    // Don't use a frame pointer on linux if optimizing for certain targets.
+    case llvm::Triple::arm:
+    case llvm::Triple::armeb:
+    case llvm::Triple::thumb:
+    case llvm::Triple::thumbeb:
+    case llvm::Triple::mips64:
+    case llvm::Triple::mips64el:
+    case llvm::Triple::mips:
+    case llvm::Triple::mipsel:
+    case llvm::Triple::systemz:
+    case llvm::Triple::x86:
+    case llvm::Triple::x86_64:
+      return !clang::driver::tools::areOptimizationsEnabled(Args);
+    default:
+      return true;
+    }
+  }
+
+  if (Triple.isOSWindows()) {
+    switch (Triple.getArch()) {
+    case llvm::Triple::x86:
+      return !clang::driver::tools::areOptimizationsEnabled(Args);
+    case llvm::Triple::x86_64:
+      return Triple.isOSBinFormatMachO();
+    case llvm::Triple::arm:
+    case llvm::Triple::thumb:
+      // Windows on ARM builds with FPO disabled to aid fast stack walking
+      return true;
+    default:
+      // All other supported Windows ISAs use xdata unwind information, so frame
+      // pointers are not generally useful.
+      return false;
+    }
+  }
+
+  return true;
+}
+
+static bool mustUseNonLeafFramePointerForTarget(const llvm::Triple &Triple) {
+  switch (Triple.getArch()) {
+  default:
+    return false;
+  case llvm::Triple::arm:
+  case llvm::Triple::thumb:
+    // ARM Darwin targets require a frame pointer to be always present to aid
+    // offline debugging via backtraces.
+    return Triple.isOSDarwin();
+  }
+}
+
+clang::CodeGenOptions::FramePointerKind
+getFramePointerKind(const llvm::opt::ArgList &Args,
+                    const llvm::Triple &Triple) {
+  // We have 4 states:
+  //
+  //  00) leaf retained, non-leaf retained
+  //  01) leaf retained, non-leaf omitted (this is invalid)
+  //  10) leaf omitted, non-leaf retained
+  //      (what -momit-leaf-frame-pointer was designed for)
+  //  11) leaf omitted, non-leaf omitted
+  //
+  //  "omit" options taking precedence over "no-omit" options is the only way
+  //  to make 3 valid states representable
+  llvm::opt::Arg *A =
+      Args.getLastArg(clang::driver::options::OPT_fomit_frame_pointer,
+                      clang::driver::options::OPT_fno_omit_frame_pointer);
+
+  bool OmitFP = A && A->getOption().matches(
+                         clang::driver::options::OPT_fomit_frame_pointer);
+  bool NoOmitFP = A && A->getOption().matches(
+                           clang::driver::options::OPT_fno_omit_frame_pointer);
+  bool OmitLeafFP =
+      Args.hasFlag(clang::driver::options::OPT_momit_leaf_frame_pointer,
+                   clang::driver::options::OPT_mno_omit_leaf_frame_pointer,
+                   Triple.isAArch64() || Triple.isPS() || Triple.isVE() ||
+                       (Triple.isAndroid() && Triple.isRISCV64()));
+  if (NoOmitFP || mustUseNonLeafFramePointerForTarget(Triple) ||
+      (!OmitFP && useFramePointerForTargetByDefault(Args, Triple))) {
+    if (OmitLeafFP)
+      return clang::CodeGenOptions::FramePointerKind::NonLeaf;
+    return clang::CodeGenOptions::FramePointerKind::All;
+  }
+  return clang::CodeGenOptions::FramePointerKind::None;
+}
+
 static void renderRpassOptions(const ArgList &Args, ArgStringList &CmdArgs,
                                const StringRef PluginOptPrefix) {
   if (const Arg *A = Args.getLastArg(options::OPT_Rpass_EQ))
     CmdArgs.push_back(Args.MakeArgString(Twine(PluginOptPrefix) +
                                          "-pass-remarks=" + A->getValue()));
 
   if (const Arg *A = Args.getLastArg(options::OPT_Rpass_missed_EQ))
     CmdArgs.push_back(Args.MakeArgString(

clang/lib/Driver/ToolChains/Flang.cpp

 //===-- Flang.cpp - Flang+LLVM ToolChain Implementations --------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 
 #include "Flang.h"
 #include "CommonArgs.h"
 
+#include "clang/Basic/CodeGenOptions.h"
 #include "clang/Driver/Options.h"
 #include "llvm/Frontend/Debug/Options.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 
 #include <cassert>
 
 using namespace clang::driver;
void Flang::ConstructJob(Compilation &C, const JobAction &JA,
   addOtherOptions(Args, CmdArgs);
 
   // Offloading related options
   addOffloadOptions(C, Inputs, JA, Args, CmdArgs);
 
   // Forward -Xflang arguments to -fc1
   Args.AddAllArgValues(CmdArgs, options::OPT_Xflang);
 
+  CodeGenOptions::FramePointerKind FPKeepKind =
+      getFramePointerKind(Args, Triple);
+
+  const char *FPKeepKindStr = nullptr;
+  switch (FPKeepKind) {
+  case CodeGenOptions::FramePointerKind::None:
+    FPKeepKindStr = "-mframe-pointer=none";
+    break;
+  case CodeGenOptions::FramePointerKind::NonLeaf:
+    FPKeepKindStr = "-mframe-pointer=non-leaf";
+    break;
+  case CodeGenOptions::FramePointerKind::All:
+    FPKeepKindStr = "-mframe-pointer=all";
+    break;
+  }
+  assert(FPKeepKindStr && "unknown FramePointerKind");
+  CmdArgs.push_back(FPKeepKindStr);
+
   // Forward -mllvm options to the LLVM option parser. In practice, this means
   // forwarding to `-fc1` as that's where the LLVM parser is run.
   for (const Arg *A : Args.filtered(options::OPT_mllvm)) {
     A->claim();
     A->render(Args, CmdArgs);
   }
 
   for (const Arg *A : Args.filtered(options::OPT_mmlir)) {

flang/test/Driver/driver-help-hidden.f90

 ! CHECK-NEXT: -fno-integrated-as      Disable the integrated assembler
 ! CHECK-NEXT: -fno-lto                Disable LTO mode (default)
 ! CHECK-NEXT: -fno-ppc-native-vector-element-order
 ! CHECK-NEXT:                         Specifies PowerPC non-native vector element order
 ! CHECK-NEXT: -fno-signed-zeros       Allow optimizations that ignore the sign of floating point zeros
 ! CHECK-NEXT: -fno-stack-arrays       Allocate array temporaries on the heap (default)
 ! CHECK-NEXT: -fno-version-loops-for-stride
 ! CHECK-NEXT:                         Do not create unit-strided loops (default)
+! CHECK-NEXT: -fomit-frame-pointer    Omit the frame pointer from functions that don't need it. Some stack unwinding cases, such as profilers and sanitizers, may prefer specifying -fno-omit-frame-pointer. On many targets, -O1 and higher omit the frame pointer by default. -m[no-]omit-leaf-frame-pointer takes precedence for leaf functions
 ! CHECK-NEXT: -fopenacc               Enable OpenACC
 ! CHECK-NEXT: -fopenmp-assume-no-nested-parallelism
 ! CHECK-NEXT:                         Assert no nested parallel regions in the GPU
 ! CHECK-NEXT: -fopenmp-assume-no-thread-state
 ! CHECK-NEXT:                         Assert no thread in a parallel region modifies an ICV
 ! CHECK-NEXT: -fopenmp-target-debug   Enable debugging in the OpenMP offloading device RTL
 ! CHECK-NEXT: -fopenmp-targets=<value>
 ! CHECK-NEXT:                         Specify comma-separated list of triples OpenMP offloading targets to be supported

flang/test/Driver/driver-help.f90

 ! HELP-NEXT: -fno-integrated-as      Disable the integrated assembler
 ! HELP-NEXT: -fno-lto                Disable LTO mode (default)
 ! HELP-NEXT: -fno-ppc-native-vector-element-order
 ! HELP-NEXT:                         Specifies PowerPC non-native vector element order
 ! HELP-NEXT: -fno-signed-zeros       Allow optimizations that ignore the sign of floating point zeros
 ! HELP-NEXT: -fno-stack-arrays       Allocate array temporaries on the heap (default)
 ! HELP-NEXT: -fno-version-loops-for-stride
 ! HELP-NEXT:                         Do not create unit-strided loops (default)
+! HELP-NEXT: -fomit-frame-pointer    Omit the frame pointer from functions that don't need it. Some stack unwinding cases, such as profilers and sanitizers, may prefer specifying -fno-omit-frame-pointer. On many targets, -O1 and higher omit the frame pointer by default. -m[no-]omit-leaf-frame-pointer takes precedence for leaf functions
 ! HELP-NEXT: -fopenacc               Enable OpenACC
 ! HELP-NEXT: -fopenmp-target-debug   Enable debugging in the OpenMP offloading device RTL
 ! HELP-NEXT: -fopenmp-targets=<value>
 ! HELP-NEXT:                         Specify comma-separated list of triples OpenMP offloading targets to be supported
 ! HELP-NEXT: -fopenmp-version=<value>
 ! HELP-NEXT:                         Set OpenMP version (e.g. 45 for OpenMP 4.5, 50 for OpenMP 5.0). Default value is 50 for Clang and 11 for Flang
 ! HELP-NEXT: -fopenmp                Parse OpenMP pragmas and generate parallel code.
 ! HELP-NEXT: -foptimization-record-file=<file>

 ! HELP-FC1-NEXT:                         Create unit-strided versions of loops
 ! HELP-FC1-NEXT: -fxor-operator          Enable .XOR. as a synonym of .NEQV.
 ! HELP-FC1-NEXT: -help                   Display available options
 ! HELP-FC1-NEXT: -init-only              Only execute frontend initialization
 ! HELP-FC1-NEXT: -I <dir>                Add directory to the end of the list of include search paths
 ! HELP-FC1-NEXT: -load <dsopath>         Load the named plugin (dynamic shared object)
 ! HELP-FC1-NEXT: -menable-no-infs        Allow optimization to assume there are no infinities.
 ! HELP-FC1-NEXT: -menable-no-nans        Allow optimization to assume there are no NaNs.
+! HELP-FC1-NEXT: -mframe-pointer=<value> Specify which frame pointers to retain.
 ! HELP-FC1-NEXT: -mllvm <value>          Additional arguments to forward to LLVM's option processing
 ! HELP-FC1-NEXT: -mmlir <value>          Additional arguments to forward to MLIR's option processing
 ! HELP-FC1-NEXT: -module-dir <dir>       Put MODULE files in <dir>
 ! HELP-FC1-NEXT: -module-suffix <suffix> Use <suffix> as the suffix for module files (the default value is `.mod`)
 ! HELP-FC1-NEXT: -mreassociate           Allow reassociation transformations for floating-point instructions
 ! HELP-FC1-NEXT: -mrelocation-model <value>
 ! HELP-FC1-NEXT:                         The relocation model to use
 ! HELP-FC1-NEXT: -nocpp                  Disable predefined and command line preprocessor macros

flang/test/Driver/frontend-forwarding.f90

 ! Test that flang-new forwards Flang frontend
 ! options to flang-new -fc1 as expected.
 
 ! RUN: %flang -fsyntax-only -### %s -o %t 2>&1 \
 ! RUN:     -finput-charset=utf-8 \
 ! RUN:     -fdefault-double-8 \
 ! RUN:     -fdefault-integer-8 \
 ! RUN:     -fdefault-real-8 \
 ! RUN:     -flarge-sizes \
 ! RUN:     -fconvert=little-endian \
 ! RUN:     -ffp-contract=fast \
 ! RUN:     -fno-honor-nans \
 ! RUN:     -fapprox-func \
 ! RUN:     -fno-signed-zeros \
 ! RUN:     -fassociative-math \
 ! RUN:     -freciprocal-math \
+! RUN:     -fomit-frame-pointer \
 ! RUN:     -fpass-plugin=Bye%pluginext \
 ! RUN:     -fversion-loops-for-stride \
 ! RUN:     -flang-experimental-polymorphism \
 ! RUN:     -flang-experimental-hlfir \
 ! RUN:     -fno-ppc-native-vector-element-order \
 ! RUN:     -fppc-native-vector-element-order \
 ! RUN:     -mllvm -print-before-all \
 ! RUN:     -save-temps=obj \

 ! CHECK: "-fppc-native-vector-element-order"
 ! CHECK: "-Rpass"
 ! CHECK: "-Rpass-missed"
 ! CHECK: "-Rpass-analysis"
 ! CHECK: "-Rno-pass"
 ! CHECK: "-Reverything"
 ! CHECK: "-Rno-everything"
 ! CHECK: "-Rpass=inline"
+! CHECK: "-mframe-pointer=none"
 ! CHECK: "-mllvm" "-print-before-all"
 ! CHECK: "-save-temps=obj"