[RISCV] Move architecture parsing code into its own function

I plan to reuse it in a later patch.

This is almost NFC except a small change in control flow when diagnosing
+d without +f.

Differential Revision: https://reviews.llvm.org/D66002

llvm-svn: 371492

clang/lib/Driver/ToolChains/Arch/RISCV.cpp

@@ -189,24 +189,23 @@ static void getExtensionFeatures(const Driver &D,
   }
 }
 
-void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
+// Returns false if an error is diagnosed.
-                                   std::vector<StringRef> &Features) {
+static bool getArchFeatures(const Driver &D, StringRef MArch,
-  if (const Arg *A = Args.getLastArg(options::OPT_march_EQ)) {
+                            std::vector<StringRef> &Features,
-    StringRef MArch = A->getValue();
+                            const ArgList &Args) {
-
   // RISC-V ISA strings must be lowercase.
   if (llvm::any_of(MArch, [](char c) { return isupper(c); })) {
     D.Diag(diag::err_drv_invalid_riscv_arch_name)
         << MArch << "string must be lowercase";
-      return;
+    return false;
   }
 
   // ISA string must begin with rv32 or rv64.
   if (!(MArch.startswith("rv32") || MArch.startswith("rv64")) ||
       (MArch.size() < 5)) {
-      D.Diag(diag::err_drv_invalid_riscv_arch_name) << MArch
+    D.Diag(diag::err_drv_invalid_riscv_arch_name)
-        << "string must begin with rv32{i,e,g} or rv64{i,g}";
+        << MArch << "string must begin with rv32{i,e,g} or rv64{i,g}";
-      return;
+    return false;
   }
 
   bool HasRV64 = MArch.startswith("rv64");
@@ -220,9 +219,9 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
   // First letter should be 'e', 'i' or 'g'.
   switch (Baseline) {
   default:
-      D.Diag(diag::err_drv_invalid_riscv_arch_name) << MArch
+    D.Diag(diag::err_drv_invalid_riscv_arch_name)
-        << "first letter should be 'e', 'i' or 'g'";
+        << MArch << "first letter should be 'e', 'i' or 'g'";
-      return;
+    return false;
   case 'e': {
     StringRef Error;
     // Currently LLVM does not support 'e'.
@@ -231,9 +230,8 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
       Error = "standard user-level extension 'e' requires 'rv32'";
     else
       Error = "unsupported standard user-level extension 'e'";
-      D.Diag(diag::err_drv_invalid_riscv_arch_name)
+    D.Diag(diag::err_drv_invalid_riscv_arch_name) << MArch << Error;
-        << MArch << Error;
+    return false;
-      return;
   }
   case 'i':
     break;
@@ -263,9 +261,9 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
   }
 
   std::string Major, Minor;
-    if (!getExtensionVersion(D, MArch, std::string(1, Baseline),
+  if (!getExtensionVersion(D, MArch, std::string(1, Baseline), Exts, Major,
-                             Exts, Major, Minor))
+                           Minor))
-      return;
+    return false;
 
   // TODO: Use version number when setting target features
   // and consume the underscore '_' that might follow.
@@ -290,7 +288,7 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
         Error = "invalid standard user-level extension";
       D.Diag(diag::err_drv_invalid_riscv_ext_arch_name)
           << MArch << Error << std::string(1, c);
-        return;
+      return false;
     }
 
     // Move to next char to prevent repeated letter.
@@ -300,9 +298,8 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
       // Skip c.
       std::string Next = std::string(std::next(I), E);
       std::string Major, Minor;
-        if (!getExtensionVersion(D, MArch, std::string(1, c),
+      if (!getExtensionVersion(D, MArch, std::string(1, c), Next, Major, Minor))
-                                 Next, Major, Minor))
+        return false;
-          return;
 
       // TODO: Use version number when setting target features
       // and consume the underscore '_' that might follow.
@@ -315,7 +312,7 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
       D.Diag(diag::err_drv_invalid_riscv_ext_arch_name)
           << MArch << "unsupported standard user-level extension"
           << std::string(1, c);
-        return;
+      return false;
     case 'm':
       Features.push_back("+m");
       break;
@@ -340,9 +337,11 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
   // It's illegal to specify the 'd' (double-precision floating point)
   // extension without also specifying the 'f' (single precision
   // floating-point) extension.
-    if (HasD && !HasF)
+  if (HasD && !HasF) {
-      D.Diag(diag::err_drv_invalid_riscv_arch_name) << MArch
+    D.Diag(diag::err_drv_invalid_riscv_arch_name)
-        << "d requires f extension to also be specified";
+        << MArch << "d requires f extension to also be specified";
+    return false;
+  }
 
   // Additional dependency checks.
   // TODO: The 'q' extension requires rv64.
@@ -350,6 +349,17 @@ void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
 
   // Handle all other types of extensions.
   getExtensionFeatures(D, Args, Features, MArch, OtherExts);
+
+  return true;
+}
+
+void riscv::getRISCVTargetFeatures(const Driver &D, const ArgList &Args,
+                                   std::vector<StringRef> &Features) {
+  if (const Arg *A = Args.getLastArg(options::OPT_march_EQ)) {
+    StringRef MArch = A->getValue();
+
+    if (!getArchFeatures(D, MArch, Features, Args))
+      return;
   }
 
   // -mrelax is default, unless -mno-relax is specified.