[mips] Rename getSupportedNanEncoding() to getIEEE754Standard() (NFC)

[abeserminji]

Summary

As function getSupportedNanEncoding() relies on IEEE 754 Standard, new suggested name is getIEEE754Standard() which is more convenient to use in decision non related to NaN encoding.

Isolated to separate patch on @atanasyan 's suggestion here D35982.

[sdardis]

LGTM with comment addressed.

lib/Driver/ToolChains/Arch/Mips.cpp

327

"are not in accordance to standard from 2008, it was first introduced in Release 3."

This should read:

"do not conform to the IEEE754-2008 standard. Support for this standard was first introduced in Release 3."

[abeserminji]

Comment resolved.

lib/Basic/Targets/Mips.h

setABI((getTriple().getArch() == llvm::Triple::mips ||
                : "n64");
 
     CPU = ABI == "o32" ? "mips32r2" : "mips64r2";
 
     CanUseBSDABICalls = Triple.getOS() == llvm::Triple::FreeBSD ||
                         Triple.getOS() == llvm::Triple::OpenBSD;
   }
 
-  bool isNaN2008Default() const {
+  bool isIEEE754_2008Default() const {
     return CPU == "mips32r6" || CPU == "mips64r6";
   }
 
   bool isFP64Default() const {
     return CPU == "mips32r6" || ABI == "n32" || ABI == "n64" || ABI == "64";
   }
 
   bool isNan2008() const override { return IsNan2008; }
const char *getClobbers() const override {
     // assembly operands if the user's assembly code doesn't use it.
     return "~{$1}";
   }
 
   bool handleTargetFeatures(std::vector<std::string> &Features,
                             DiagnosticsEngine &Diags) override {
     IsMips16 = false;
     IsMicromips = false;
-    IsNan2008 = isNaN2008Default();
+    IsNan2008 = isIEEE754_2008Default();
     IsSingleFloat = false;
     FloatABI = HardFloat;
     DspRev = NoDSP;
     HasFP64 = isFP64Default();
 
     for (const auto &Feature : Features) {
       if (Feature == "+single-float")
         IsSingleFloat = true;

lib/Driver/ToolChains/Arch/Mips.h

 
 namespace clang {
 namespace driver {
 namespace tools {
 
 bool isMipsArch(llvm::Triple::ArchType Arch);
 
 namespace mips {
-typedef enum { NanLegacy = 1, Nan2008 = 2 } NanEncoding;
+typedef enum { Legacy = 1, Std2008 = 2 } IEEE754Standard;
 
 enum class FloatABI {
   Invalid,
   Soft,
   Hard,
 };
 
-NanEncoding getSupportedNanEncoding(StringRef &CPU);
+IEEE754Standard getIEEE754Standard(StringRef &CPU);
 bool hasCompactBranches(StringRef &CPU);
 void getMipsCPUAndABI(const llvm::opt::ArgList &Args,
                       const llvm::Triple &Triple, StringRef &CPUName,
                       StringRef &ABIName);
 void getMIPSTargetFeatures(const Driver &D, const llvm::Triple &Triple,
                            const llvm::opt::ArgList &Args,
                            std::vector<StringRef> &Features);
 StringRef getGnuCompatibleMipsABIName(StringRef ABI);

lib/Driver/ToolChains/Arch/Mips.cpp

if (FloatABI == mips::FloatABI::Soft) {
     // mode to the MipsTargetInfoBase to define appropriate macros there.
     // Now it is the only method.
     Features.push_back("+soft-float");
   }
 
   if (Arg *A = Args.getLastArg(options::OPT_mnan_EQ)) {
     StringRef Val = StringRef(A->getValue());
     if (Val == "2008") {
-      if (mips::getSupportedNanEncoding(CPUName) & mips::Nan2008)
+      if (mips::getIEEE754Standard(CPUName) & mips::Std2008)
         Features.push_back("+nan2008");
       else {
         Features.push_back("-nan2008");
         D.Diag(diag::warn_target_unsupported_nan2008) << CPUName;
       }
     } else if (Val == "legacy") {
-      if (mips::getSupportedNanEncoding(CPUName) & mips::NanLegacy)
+      if (mips::getIEEE754Standard(CPUName) & mips::Legacy)
         Features.push_back("-nan2008");
       else {
         Features.push_back("+nan2008");
         D.Diag(diag::warn_target_unsupported_nanlegacy) << CPUName;
       }
     } else
       D.Diag(diag::err_drv_unsupported_option_argument)
           << A->getOption().getName() << Val;
void mips::getMIPSTargetFeatures(const Driver &D, const llvm::Triple &Triple,
 
   AddTargetFeature(Args, Features, options::OPT_mno_odd_spreg,
                    options::OPT_modd_spreg, "nooddspreg");
   AddTargetFeature(Args, Features, options::OPT_mno_madd4, options::OPT_mmadd4,
                    "nomadd4");
   AddTargetFeature(Args, Features, options::OPT_mmt, options::OPT_mno_mt, "mt");
 }
 
-mips::NanEncoding mips::getSupportedNanEncoding(StringRef &CPU) {
-  // Strictly speaking, mips32r2 and mips64r2 are NanLegacy-only since Nan2008
-  // was first introduced in Release 3. However, other compilers have
-  // traditionally allowed it for Release 2 so we should do the same.
-  return (NanEncoding)llvm::StringSwitch<int>(CPU)
-      .Case("mips1", NanLegacy)
-      .Case("mips2", NanLegacy)
-      .Case("mips3", NanLegacy)
-      .Case("mips4", NanLegacy)
-      .Case("mips5", NanLegacy)
-      .Case("mips32", NanLegacy)
-      .Case("mips32r2", NanLegacy | Nan2008)
-      .Case("mips32r3", NanLegacy | Nan2008)
-      .Case("mips32r5", NanLegacy | Nan2008)
-      .Case("mips32r6", Nan2008)
-      .Case("mips64", NanLegacy)
-      .Case("mips64r2", NanLegacy | Nan2008)
-      .Case("mips64r3", NanLegacy | Nan2008)
-      .Case("mips64r5", NanLegacy | Nan2008)
-      .Case("mips64r6", Nan2008)
-      .Default(NanLegacy);
+mips::IEEE754Standard mips::getIEEE754Standard(StringRef &CPU) {
+  // Strictly speaking, mips32r2 and mips64r2 do not conform to the
+  // IEEE754-2008 standard. Support for this standard was first introduced
+  // in Release 3. However, other compilers have traditionally allowed it
+  // for Release 2 so we should do the same.
+  return (IEEE754Standard)llvm::StringSwitch<int>(CPU)
+      .Case("mips1", Legacy)
+      .Case("mips2", Legacy)
+      .Case("mips3", Legacy)
+      .Case("mips4", Legacy)
+      .Case("mips5", Legacy)
+      .Case("mips32", Legacy)
+      .Case("mips32r2", Legacy | Std2008)
+      .Case("mips32r3", Legacy | Std2008)
+      .Case("mips32r5", Legacy | Std2008)
+      .Case("mips32r6", Std2008)
+      .Case("mips64", Legacy)
+      .Case("mips64r2", Legacy | Std2008)
+      .Case("mips64r3", Legacy | Std2008)
+      .Case("mips64r5", Legacy | Std2008)
+      .Case("mips64r6", Std2008)
+      .Default(Std2008);
 }
 
 bool mips::hasCompactBranches(StringRef &CPU) {
   // mips32r6 and mips64r6 have compact branches.
   return llvm::StringSwitch<bool>(CPU)
       .Case("mips32r6", true)
       .Case("mips64r6", true)
       .Default(false);