[RISCV] Remove duplicated logic when determining the target ABI

[rogfer01]

Summary

We were calculating twice ilp32/lp64. Do this just in one place instead.

[rogfer01]

lib/Driver/ToolChains/Arch/RISCV.cpp

381

When 64-bit is upstreamed and lp64d implemented, I plan to default riscv64-unknown-linux-gnu to lp64d here.

Does this sound sensible?

[rogfer01]

Ping?

[rogfer01]

@asb in D59298 I call riscv::getRISCVABI for ClangAs, does it make sense to make the same change for Clang here?

Thank you.

[lenary]

Given we now have support for the floating-point ABIs, can you rebase and update this patch?

[rogfer01]

Hi @lenary, sure I can rebase this.

However, I think it may be better to do the lp64d change in another phab so we can keep this one NFC.

[rogfer01]

ChangeLog

• Rebase change

[lenary]

Ok, sure! I think I'm happy for this to land then.

[rogfer01]

Thanks @lenary ! I will commit this shortly.

lib/Driver/ToolChains/Arch/RISCV.cpp

void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
   }
 
   // Now add any that the user explicitly requested on the command line,
   // which may override the defaults.
   handleTargetFeaturesGroup(Args, Features, options::OPT_m_riscv_Features_Group);
 }
 
 StringRef riscv::getRISCVABI(const ArgList &Args, const llvm::Triple &Triple) {
-  if (Arg *A = Args.getLastArg(options::OPT_mabi_EQ))
+  assert((Triple.getArch() == llvm::Triple::riscv32 ||
+          Triple.getArch() == llvm::Triple::riscv64) &&
+         "Unexpected triple");
+
+  if (const Arg *A = Args.getLastArg(options::OPT_mabi_EQ))
     return A->getValue();
 
+  // FIXME: currently defaults to the soft-float ABIs. Will need to be
+  // expanded to select ilp32f, ilp32d, lp64f, lp64d when appropriate.
   return Triple.getArch() == llvm::Triple::riscv32 ? "ilp32" : "lp64";
 }

lib/Driver/ToolChains/Clang.cpp

void Clang::AddPPCTargetArgs(const ArgList &Args,
   if (ABIName) {
     CmdArgs.push_back("-target-abi");
     CmdArgs.push_back(ABIName);
   }
 }
 
 void Clang::AddRISCVTargetArgs(const ArgList &Args,
                                ArgStringList &CmdArgs) const {
-  // FIXME: currently defaults to the soft-float ABIs. Will need to be
-  // expanded to select ilp32f, ilp32d, lp64f, lp64d when appropriate.
-  const char *ABIName = nullptr;
   const llvm::Triple &Triple = getToolChain().getTriple();
-  if (Arg *A = Args.getLastArg(options::OPT_mabi_EQ))
-    ABIName = A->getValue();
-  else if (Triple.getArch() == llvm::Triple::riscv32)
-    ABIName = "ilp32";
-  else if (Triple.getArch() == llvm::Triple::riscv64)
-    ABIName = "lp64";
-  else
-    llvm_unreachable("Unexpected triple!");
+  StringRef ABIName = riscv::getRISCVABI(Args, Triple);
 
   CmdArgs.push_back("-target-abi");
-  CmdArgs.push_back(ABIName);
+  CmdArgs.push_back(ABIName.data());
 }
 
 void Clang::AddSparcTargetArgs(const ArgList &Args,
                                ArgStringList &CmdArgs) const {
   sparc::FloatABI FloatABI =
       sparc::getSparcFloatABI(getToolChain().getDriver(), Args);
 
   if (FloatABI == sparc::FloatABI::Soft) {