Revert "Add __builtin_set_flt_rounds"

This reverts commit 24b823554a.

These changes broke the PPC build bot.

clang/include/clang/Basic/Builtins.def

@@ -397,7 +397,6 @@ BUILTIN(__builtin_truncf16, "hh", "Fnc")
 
 // Access to floating point environment
 BUILTIN(__builtin_flt_rounds, "i", "n")
-BUILTIN(__builtin_set_flt_rounds, "vi", "n")
 
 // C99 complex builtins
 BUILTIN(__builtin_cabs, "dXd", "Fne")

clang/lib/CodeGen/CGBuiltin.cpp

@@ -3375,14 +3375,6 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
     return RValue::get(Result);
   }
 
-  case Builtin::BI__builtin_set_flt_rounds: {
-    Function *F = CGM.getIntrinsic(Intrinsic::set_rounding);
-
-    Value *V = EmitScalarExpr(E->getArg(0));
-    Builder.CreateCall(F, V);
-    return RValue::get(nullptr);
-  }
-
   case Builtin::BI__builtin_fpclassify: {
     CodeGenFunction::CGFPOptionsRAII FPOptsRAII(*this, E);
     // FIXME: for strictfp/IEEE-754 we need to not trap on SNaN here.

clang/lib/Sema/SemaChecking.cpp

@@ -2146,14 +2146,6 @@ Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID,
       return ExprError();
     break;
 
-  case Builtin::BI__builtin_set_flt_rounds:
-    if (CheckBuiltinTargetInSupported(*this, BuiltinID, TheCall,
-                                      {llvm::Triple::x86, llvm::Triple::x86_64,
-                                       llvm::Triple::arm, llvm::Triple::thumb,
-                                       llvm::Triple::aarch64}))
-      return ExprError();
-    break;
-
   case Builtin::BI__builtin_isgreater:
   case Builtin::BI__builtin_isgreaterequal:
   case Builtin::BI__builtin_isless:

clang/test/CodeGen/builtins.c

@@ -278,8 +278,6 @@ void test_float_builtins(__fp16 *H, float F, double D, long double LD) {
 
   res = __builtin_flt_rounds();
   // CHECK: call i32 @llvm.get.rounding(
-  __builtin_set_flt_rounds(1);
-  // CHECK: call void @llvm.set.rounding(i32 1)
 }
 
 // CHECK-LABEL: define{{.*}} void @test_float_builtin_ops