Add support for a limited subset of TS 18661-3 math builtins.

These just overloads for _Float128. They're supported by GCC 7 and used
by glibc. APFloat support is already there so just add the overloads.

__builtin_copysignf128
__builtin_fabsf128
__builtin_huge_valf128
__builtin_inff128
__builtin_nanf128
__builtin_nansf128

This is the same support that GCC has, according to the documentation,
but limited to _Float128.

llvm-svn: 321948

3 files changed, 14 insertions, 4 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index b9a23ed9642..2e906247cc1 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -8929,10 +8929,12 @@ static QualType DecodeTypeFromStr(const char *&Str, const ASTContext &Context,
     Type = Context.FloatTy;
     break;
   case 'd':
-    assert(HowLong < 2 && !Signed && !Unsigned &&
+    assert(HowLong < 3 && !Signed && !Unsigned &&
            "Bad modifiers used with 'd'!");
-    if (HowLong)
+    if (HowLong == 1)
       Type = Context.LongDoubleTy;
+    else if (HowLong == 2)
+      Type = Context.Float128Ty;
     else
       Type = Context.DoubleTy;
     break;
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 8d9b3c3bebc..6cbb498abde 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -9170,9 +9170,11 @@ bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
   case Builtin::BI__builtin_huge_val:
   case Builtin::BI__builtin_huge_valf:
   case Builtin::BI__builtin_huge_vall:
+  case Builtin::BI__builtin_huge_valf128:
   case Builtin::BI__builtin_inf:
   case Builtin::BI__builtin_inff:
-  case Builtin::BI__builtin_infl: {
+  case Builtin::BI__builtin_infl:
+  case Builtin::BI__builtin_inff128: {
     const llvm::fltSemantics &Sem =
       Info.Ctx.getFloatTypeSemantics(E->getType());
     Result = llvm::APFloat::getInf(Sem);
@@ -9182,6 +9184,7 @@ bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
   case Builtin::BI__builtin_nans:
   case Builtin::BI__builtin_nansf:
   case Builtin::BI__builtin_nansl:
+  case Builtin::BI__builtin_nansf128:
     if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0),
                                true, Result))
       return Error(E);
@@ -9190,6 +9193,7 @@ bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
   case Builtin::BI__builtin_nan:
   case Builtin::BI__builtin_nanf:
   case Builtin::BI__builtin_nanl:
+  case Builtin::BI__builtin_nanf128:
     // If this is __builtin_nan() turn this into a nan, otherwise we
     // can't constant fold it.
     if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0),
@@ -9200,6 +9204,7 @@ bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
   case Builtin::BI__builtin_fabs:
   case Builtin::BI__builtin_fabsf:
   case Builtin::BI__builtin_fabsl:
+  case Builtin::BI__builtin_fabsf128:
     if (!EvaluateFloat(E->getArg(0), Result, Info))
       return false;
 
@@ -9213,7 +9218,8 @@ bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
 
   case Builtin::BI__builtin_copysign:
   case Builtin::BI__builtin_copysignf:
-  case Builtin::BI__builtin_copysignl: {
+  case Builtin::BI__builtin_copysignl:
+  case Builtin::BI__builtin_copysignf128: {
     APFloat RHS(0.);
     if (!EvaluateFloat(E->getArg(0), Result, Info) ||
         !EvaluateFloat(E->getArg(1), RHS, Info))
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 35ae114c4f2..631085a979d 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -966,6 +966,7 @@ RValue CodeGenFunction::EmitBuiltinExpr(const FunctionDecl *FD,
     case Builtin::BI__builtin_copysign:
     case Builtin::BI__builtin_copysignf:
     case Builtin::BI__builtin_copysignl:
+    case Builtin::BI__builtin_copysignf128:
       return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::copysign));
 
     case Builtin::BIcos:
@@ -998,6 +999,7 @@ RValue CodeGenFunction::EmitBuiltinExpr(const FunctionDecl *FD,
     case Builtin::BI__builtin_fabs:
     case Builtin::BI__builtin_fabsf:
     case Builtin::BI__builtin_fabsl:
+    case Builtin::BI__builtin_fabsf128:
       return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::fabs));
 
     case Builtin::BIfloor: