Clang: Add minnum/maxnum builtin functions support

With #112852, we claimed
that llvm.minnum and llvm.maxnum should treat +0.0>-0.0,
while libc doesn't require fmin(3)/fmax(3) for it.

To make llvm.minnum/llvm.maxnum easy to use, we define the builtin
functions for them, include
    __builtin_minnum
    __builtin_elementwise_minnum
    __builtin_minnum
    __builtin_elementwise_minnum
    __builtin_minnum
    __builtin_elementwise_minnum
    __builtin_minnum
    __builtin_maxnum
    __builtin_elementwise_maxnum
    __builtin_maxnum
    __builtin_elementwise_maxnum
    __builtin_maxnum
    __builtin_elementwise_maxnum
    __builtin_maxnum

All of them support _Float16, float, double, long double.

Author: wzssyqa

clang/include/clang/Basic/Builtins.td

@@ -209,6 +209,18 @@ def FmaxF16F128 : Builtin, F16F128MathTemplate {
   let Prototype = "T(T, T)";
 }
 
+def MinNum : Builtin {
+  let Spellings = ["__builtin_minnum"];
+  let Attributes = [FunctionWithBuiltinPrefix, NoThrow, Const, CustomTypeChecking, Constexpr];
+  let Prototype = "void(...)";
+}
+
+def MaxNum : Builtin {
+  let Spellings = ["__builtin_maxnum"];
+  let Attributes = [FunctionWithBuiltinPrefix, NoThrow, Const, CustomTypeChecking, Constexpr];
+  let Prototype = "void(...)";
+}
+
 def FminF16F128 : Builtin, F16F128MathTemplate {
   let Spellings = ["__builtin_fmin"];
   let Attributes = [FunctionWithBuiltinPrefix, NoThrow, Const, Constexpr];
@@ -1304,6 +1316,18 @@ def ElementwiseMin : Builtin {
   let Prototype = "void(...)";
 }
 
+def ElementwiseMaxNum : Builtin {
+  let Spellings = ["__builtin_elementwise_maxnum"];
+  let Attributes = [NoThrow, Const, CustomTypeChecking];
+  let Prototype = "void(...)";
+}
+
+def ElementwiseMinNum : Builtin {
+  let Spellings = ["__builtin_elementwise_minnum"];
+  let Attributes = [NoThrow, Const, CustomTypeChecking];
+  let Prototype = "void(...)";
+}
+
 def ElementwiseMaximum : Builtin {
   let Spellings = ["__builtin_elementwise_maximum"];
   let Attributes = [NoThrow, Const, CustomTypeChecking];

clang/include/clang/Sema/Sema.h

@@ -2597,6 +2597,7 @@ class Sema final : public SemaBase {
   ExprResult AtomicOpsOverloaded(ExprResult TheCallResult,
                                  AtomicExpr::AtomicOp Op);
 
+  bool BuiltinMaxNumMinNumMath(CallExpr *TheCall);
   /// \param FPOnly restricts the arguments to floating-point types.
   bool BuiltinElementwiseMath(CallExpr *TheCall,
                               EltwiseBuiltinArgTyRestriction ArgTyRestr =

clang/lib/CodeGen/CGBuiltin.cpp

@@ -2629,6 +2629,16 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
                                    Intrinsic::minnum,
                                    Intrinsic::experimental_constrained_minnum));
 
+    case Builtin::BI__builtin_maxnum:
+      return RValue::get(emitBinaryMaybeConstrainedFPBuiltin(
+          *this, E, Intrinsic::maxnum,
+          Intrinsic::experimental_constrained_maxnum));
+
+    case Builtin::BI__builtin_minnum:
+      return RValue::get(emitBinaryMaybeConstrainedFPBuiltin(
+          *this, E, Intrinsic::minnum,
+          Intrinsic::experimental_constrained_minnum));
+
     case Builtin::BIfmaximum_num:
     case Builtin::BIfmaximum_numf:
     case Builtin::BIfmaximum_numl:
@@ -3818,6 +3828,22 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
     return RValue::get(Result);
   }
 
+  case Builtin::BI__builtin_elementwise_maxnum: {
+    Value *Op0 = EmitScalarExpr(E->getArg(0));
+    Value *Op1 = EmitScalarExpr(E->getArg(1));
+    Value *Result = Builder.CreateBinaryIntrinsic(llvm::Intrinsic::maxnum, Op0,
+                                                  Op1, nullptr, "elt.maxnum");
+    return RValue::get(Result);
+  }
+
+  case Builtin::BI__builtin_elementwise_minnum: {
+    Value *Op0 = EmitScalarExpr(E->getArg(0));
+    Value *Op1 = EmitScalarExpr(E->getArg(1));
+    Value *Result = Builder.CreateBinaryIntrinsic(llvm::Intrinsic::minnum, Op0,
+                                                  Op1, nullptr, "elt.minnum");
+    return RValue::get(Result);
+  }
+
   case Builtin::BI__builtin_elementwise_maximum: {
     Value *Op0 = EmitScalarExpr(E->getArg(0));
     Value *Op1 = EmitScalarExpr(E->getArg(1));

clang/lib/Sema/SemaChecking.cpp

@@ -2760,8 +2760,17 @@ Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID,
       return ExprError();
     break;
 
+  case Builtin::BI__builtin_minnum:
+  case Builtin::BI__builtin_maxnum: {
+    if (BuiltinMaxNumMinNumMath(TheCall))
+      return ExprError();
+    break;
+  }
+
   // These builtins restrict the element type to floating point
   // types only, and take in two arguments.
+  case Builtin::BI__builtin_elementwise_minnum:
+  case Builtin::BI__builtin_elementwise_maxnum:
   case Builtin::BI__builtin_elementwise_minimum:
   case Builtin::BI__builtin_elementwise_maximum:
   case Builtin::BI__builtin_elementwise_atan2:
@@ -15278,6 +15287,42 @@ bool Sema::PrepareBuiltinElementwiseMathOneArgCall(
   return false;
 }
 
+bool Sema::BuiltinMaxNumMinNumMath(CallExpr *TheCall) {
+  if (checkArgCount(TheCall, 2))
+    return true;
+
+  ExprResult OrigArg0 = TheCall->getArg(0);
+  ExprResult OrigArg1 = TheCall->getArg(1);
+
+  // Do standard promotions between the two arguments, returning their common
+  // type.
+  QualType Res = UsualArithmeticConversions(
+      OrigArg0, OrigArg1, TheCall->getExprLoc(), ACK_Comparison);
+  if (OrigArg0.isInvalid() || OrigArg1.isInvalid())
+    return true;
+
+  // Make sure any conversions are pushed back into the call; this is
+  // type safe since unordered compare builtins are declared as "_Bool
+  // foo(...)".
+  TheCall->setArg(0, OrigArg0.get());
+  TheCall->setArg(1, OrigArg1.get());
+
+  if (!OrigArg0.get()->isTypeDependent() && OrigArg1.get()->isTypeDependent())
+    return true;
+
+  // If the common type isn't a real floating type, then the arguments were
+  // invalid for this operation.
+  if (Res.isNull() || !Res->isRealFloatingType())
+    return Diag(OrigArg0.get()->getBeginLoc(),
+                diag::err_typecheck_call_invalid_ordered_compare)
+           << OrigArg0.get()->getType() << OrigArg1.get()->getType()
+           << SourceRange(OrigArg0.get()->getBeginLoc(),
+                          OrigArg1.get()->getEndLoc());
+
+  TheCall->setType(Res);
+  return false;
+}
+
 bool Sema::BuiltinElementwiseMath(CallExpr *TheCall,
                                   EltwiseBuiltinArgTyRestriction ArgTyRestr) {
   if (auto Res = BuiltinVectorMath(TheCall, ArgTyRestr); Res.has_value()) {