Fix the return types of dot4add_i8packed and dot4add_u8packed.

tools/clang/lib/Sema/SemaHLSL.cpp

@@ -6737,8 +6737,8 @@ bool HLSLExternalSource::MatchArguments(
           (iArg != retArgIdx && retTypeIdx == pIntrinsicArg->uComponentTypeId);
       // For literal arg which don't affect return type, find concrete type.
       // For literal arg affect return type,
-      //   TryEvalIntrinsic in CGHLSLMS.cpp will take care of cases
-      //     where all argumentss are literal.
+      //   TryEvalIntrinsic in CGHLSLMSFinishCodeGen.cpp will take care of
+      //     cases where all arguments are literal.
       //   CombineBasicTypes will cover the rest cases.
       if (!affectRetType) {
         TypeInfoEltKind =

tools/clang/test/DXC/dot4add_i8_u8_packed-types.hlsl

@@ -0,0 +1,34 @@
+// RUN: %dxc /enable-16bit-types /T cs_6_8 %s | FileCheck %s
+
+// Compiling this HLSL would fail this assertion in TranslateDot4AddPacked:
+//
+//     DXASSERT(
+//         !accTy->isVectorTy() && accTy->isIntegerTy(32),
+//         "otherwise, unexpected vector support in high level intrinsic template");
+//
+// Bug was fixed by changing the declarations of dot4add_i8packed and
+// dot4add_u8packed in utils/hct/gen_intrin_main.txt to simply write
+// out their argument and return types, rather than using the $typeN
+// reference syntax.
+
+// CHECK: call i32 @dx.op.dot4AddPacked.i32{{.*}}Dot4AddI8Packed(acc,a,b)
+// CHECK: call i32 @dx.op.dot4AddPacked.i32{{.*}}Dot4AddU8Packed(acc,a,b)
+// CHECK: call float @dx.op.dot2AddHalf.f32{{.*}}Dot2AddHalf(acc,ax,ay,bx,by)
+
+RWByteAddressBuffer buf;
+
+[numthreads(1, 1, 1)]
+void main()
+{
+    int a = dot4add_i8packed(0, 0, 0);
+    int b = dot4add_i8packed(0, 0, a);
+    buf.Store<int>(0, b);
+
+    uint c = dot4add_u8packed(0, 0, 0);
+    uint d = dot4add_u8packed(0, 0, c);
+    buf.Store<uint>(4, d);
+
+    float e = dot2add(half2(0,0), half2(0,0), 1.0);
+    float f = dot2add(half2(0,0), half2(0,0), e);
+    buf.Store<float>(8, f);
+}

utils/hct/gen_intrin_main.txt

@@ -339,9 +339,9 @@ float<4,3> [[rn]] ObjectToWorld4x3();
 float<4,3> [[rn]] WorldToObject4x3();
 
 // Packed dot products with accumulate:
-$type3 [[rn]] dot4add_u8packed(in uint a, in $type1 b, in uint c);
-$type3 [[rn]] dot4add_i8packed(in uint a, in $type1 b, in int c);
-$type3 [[rn]] dot2add(in float16_t<2> a, in $type1 b, in float c);
+uint [[rn]] dot4add_u8packed(in uint a, in $type1 b, in uint c);
+int [[rn]] dot4add_i8packed(in uint a, in $type1 b, in int c);
+float [[rn]] dot2add(in float16_t<2> a, in $type1 b, in float c);
 
 // Unpacking intrinsics
 int16_t<4> [[rn]] unpack_s8s16(in p32i8 pk);