fixup! [clang] Implement __builtin_{clzg,ctzg}

Author: overmighty

clang/include/clang/Basic/Builtins.td

@@ -660,8 +660,6 @@ def Clz : Builtin, BitShort_Int_Long_LongLongTemplate {
   let Prototype = "int(unsigned T)";
 }
 
-// FIXME: Add int clzimax(uintmax_t)
-
 def Clzg : Builtin {
   let Spellings = ["__builtin_clzg"];
   let Attributes = [NoThrow, Const, CustomTypeChecking];
@@ -674,8 +672,6 @@ def Ctz : Builtin, BitShort_Int_Long_LongLongTemplate {
   let Prototype = "int(unsigned T)";
 }
 
-// FIXME: Add int ctzimax(uintmax_t)
-
 def Ctzg : Builtin {
   let Spellings = ["__builtin_ctzg"];
   let Attributes = [NoThrow, Const, CustomTypeChecking];

clang/lib/CodeGen/CGBuiltin.cpp

@@ -3141,7 +3141,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
     Function *F = CGM.getIntrinsic(Intrinsic::cttz, ArgType);
 
     llvm::Type *ResultType = ConvertType(E->getType());
-    Value *ZeroUndef = Builder.getInt1(getTarget().isCLZForZeroUndef());
+    Value *ZeroUndef =
+        Builder.getInt1(HasFallback || getTarget().isCLZForZeroUndef());
     Value *Result = Builder.CreateCall(F, {ArgValue, ZeroUndef});
     if (Result->getType() != ResultType)
       Result = Builder.CreateIntCast(Result, ResultType, /*isSigned*/true,
@@ -3172,7 +3173,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
     Function *F = CGM.getIntrinsic(Intrinsic::ctlz, ArgType);
 
     llvm::Type *ResultType = ConvertType(E->getType());
-    Value *ZeroUndef = Builder.getInt1(getTarget().isCLZForZeroUndef());
+    Value *ZeroUndef =
+        Builder.getInt1(HasFallback || getTarget().isCLZForZeroUndef());
     Value *Result = Builder.CreateCall(F, {ArgValue, ZeroUndef});
     if (Result->getType() != ResultType)
       Result = Builder.CreateIntCast(Result, ResultType, /*isSigned*/true,

clang/lib/Sema/SemaChecking.cpp

@@ -2237,7 +2237,7 @@ static bool SemaBuiltinCountZeroBitsGeneric(Sema &S, CallExpr *TheCall) {
   }
 
   if (TheCall->getNumArgs() > 1) {
-    ExprResult Arg1Res = S.DefaultLvalueConversion(TheCall->getArg(1));
+    ExprResult Arg1Res = S.UsualUnaryConversions(TheCall->getArg(1));
     if (Arg1Res.isInvalid())
       return true;
 
@@ -2246,12 +2246,6 @@ static bool SemaBuiltinCountZeroBitsGeneric(Sema &S, CallExpr *TheCall) {
 
     QualType Arg1Ty = Arg1->getType();
 
-    if (S.Context.isPromotableIntegerType(Arg1Ty)) {
-      Arg1Ty = S.Context.getPromotedIntegerType(Arg1Ty);
-      Arg1 = S.ImpCastExprToType(Arg1, Arg1Ty, CK_IntegralCast).get();
-      TheCall->setArg(1, Arg1);
-    }
-
     if (!Arg1Ty->isSpecificBuiltinType(BuiltinType::Int)) {
       S.Diag(Arg1->getBeginLoc(), diag::err_builtin_invalid_arg_type)
           << 2 << /*'int' ty*/ 8 << Arg1Ty;