Enable support for __float128 in Clang

This patch corresponds to review:
http://reviews.llvm.org/D15120

It adds support for the __float128 keyword, literals and a target feature to
enable it. This support is disabled by default on all targets and any target
that has support for this type is free to add it.

Based on feedback that I've received from target maintainers, this appears to
be the right thing for most targets. I have not heard from the maintainers of
X86 which I believe supports this type. I will subsequently investigate the
impact of enabling this on X86.

llvm-svn: 266186

2 files changed, 25 insertions, 5 deletions

diff --git a/clang/lib/Basic/TargetInfo.cpp b/clang/lib/Basic/TargetInfo.cpp
index 40d6001e532..c287073ead9 100644
--- a/clang/lib/Basic/TargetInfo.cpp
+++ b/clang/lib/Basic/TargetInfo.cpp
@@ -46,6 +46,7 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : TargetOpts(), Triple(T) {
   DoubleAlign = 64;
   LongDoubleWidth = 64;
   LongDoubleAlign = 64;
+  Float128Align = 128;
   LargeArrayMinWidth = 0;
   LargeArrayAlign = 0;
   MaxAtomicPromoteWidth = MaxAtomicInlineWidth = 0;
@@ -72,6 +73,7 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : TargetOpts(), Triple(T) {
   FloatFormat = &llvm::APFloat::IEEEsingle;
   DoubleFormat = &llvm::APFloat::IEEEdouble;
   LongDoubleFormat = &llvm::APFloat::IEEEdouble;
+  Float128Format = &llvm::APFloat::IEEEquad;
   MCountName = "mcount";
   RegParmMax = 0;
   SSERegParmMax = 0;
@@ -223,6 +225,8 @@ TargetInfo::RealType TargetInfo::getRealTypeByWidth(unsigned BitWidth) const {
     if (&getLongDoubleFormat() == &llvm::APFloat::PPCDoubleDouble ||
         &getLongDoubleFormat() == &llvm::APFloat::IEEEquad)
       return LongDouble;
+    if (hasFloat128Type())
+      return Float128;
     break;
   }
 
diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index 7639b04d25a..4cce9cbd8a2 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -806,6 +806,7 @@ class PPCTargetInfo : public TargetInfo {
   bool HasHTM;
   bool HasBPERMD;
   bool HasExtDiv;
+  bool HasFloat128;
 
 protected:
   std::string ABI;
@@ -814,7 +815,7 @@ public:
   PPCTargetInfo(const llvm::Triple &Triple, const TargetOptions &)
     : TargetInfo(Triple), HasVSX(false), HasP8Vector(false),
       HasP8Crypto(false), HasDirectMove(false), HasQPX(false), HasHTM(false),
-      HasBPERMD(false), HasExtDiv(false) {
+      HasBPERMD(false), HasExtDiv(false), HasFloat128(false) {
     BigEndian = (Triple.getArch() != llvm::Triple::ppc64le);
     SimdDefaultAlign = 128;
     LongDoubleWidth = LongDoubleAlign = 128;
@@ -1058,6 +1059,9 @@ public:
            LongDoubleFormat == &llvm::APFloat::PPCDoubleDouble &&
            getTriple().isOSBinFormatELF();
   }
+  bool hasFloat128Type() const override {
+    return HasFloat128;
+  }
 };
 
 const Builtin::Info PPCTargetInfo::BuiltinInfo[] = {
@@ -1089,6 +1093,8 @@ bool PPCTargetInfo::handleTargetFeatures(std::vector<std::string> &Features,
       HasQPX = true;
     } else if (Feature == "+htm") {
       HasHTM = true;
+    } else if (Feature == "+float128") {
+      HasFloat128 = true;
     }
     // TODO: Finish this list and add an assert that we've handled them
     // all.
@@ -1246,6 +1252,8 @@ void PPCTargetInfo::getTargetDefines(const LangOptions &Opts,
     Builder.defineMacro("__CRYPTO__");
   if (HasHTM)
     Builder.defineMacro("__HTM__");
+  if (HasFloat128)
+    Builder.defineMacro("__FLOAT128__");
 
   Builder.defineMacro("__GCC_HAVE_SYNC_COMPARE_AND_SWAP_1");
   Builder.defineMacro("__GCC_HAVE_SYNC_COMPARE_AND_SWAP_2");
@@ -1296,6 +1304,13 @@ static bool ppcUserFeaturesCheck(DiagnosticsEngine &Diags,
                                                      << "-mno-vsx";
       return false;
     }
+
+    if (std::find(FeaturesVec.begin(), FeaturesVec.end(), "+float128") !=
+        FeaturesVec.end()) {
+      Diags.Report(diag::err_opt_not_valid_with_opt) << "-mfloat128"
+                                                     << "-mno-vsx";
+      return false;
+    }
   }
 
   return true;
@@ -1364,6 +1379,7 @@ bool PPCTargetInfo::hasFeature(StringRef Feature) const {
     .Case("htm", HasHTM)
     .Case("bpermd", HasBPERMD)
     .Case("extdiv", HasExtDiv)
+    .Case("float128", HasFloat128)
     .Default(false);
 }
 
@@ -1373,19 +1389,19 @@ void PPCTargetInfo::setFeatureEnabled(llvm::StringMap<bool> &Features,
   // as well. Do the inverse if we're disabling vsx. We'll diagnose any user
   // incompatible options.
   if (Enabled) {
-    if (Name == "vsx") {
-     Features[Name] = true;
-    } else if (Name == "direct-move") {
+    if (Name == "direct-move") {
       Features[Name] = Features["vsx"] = true;
     } else if (Name == "power8-vector") {
       Features[Name] = Features["vsx"] = true;
+    } else if (Name == "float128") {
+      Features[Name] = Features["vsx"] = true;
     } else {
       Features[Name] = true;
     }
   } else {
     if (Name == "vsx") {
       Features[Name] = Features["direct-move"] = Features["power8-vector"] =
-          false;
+          Features["float128"] = false;
     } else {
       Features[Name] = false;
     }