[llvm] [SPIRV] Use `Op[S|U]Dot` when possible for integer dot product (PR #115095)

[Finn Plummer via llvm-commits]

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@@ -27,28 +57,49 @@ define noundef i32 @dot_int4(<4 x i32> noundef %a, <4 x i32> noundef %b) {
 entry:
 ; CHECK: %[[#arg0:]] = OpFunctionParameter %[[#vec4_int_32]]
 ; CHECK: %[[#arg1:]] = OpFunctionParameter %[[#vec4_int_32]]
-; CHECK: %[[#mul_vec:]] = OpIMul %[[#vec4_int_32]] %[[#arg0]] %[[#arg1]]
-; CHECK: %[[#elt0:]] = OpCompositeExtract %[[#int_32]] %[[#mul_vec]] 0
-; CHECK: %[[#elt1:]] = OpCompositeExtract %[[#int_32]] %[[#mul_vec]] 1
-; CHECK: %[[#sum0:]] = OpIAdd %[[#int_32]] %[[#elt0]] %[[#elt1]]
-; CHECK: %[[#elt2:]] = OpCompositeExtract %[[#int_32]] %[[#mul_vec]] 2
-; CHECK: %[[#sum1:]] = OpIAdd %[[#int_32]] %[[#sum0]] %[[#elt2]]
-; CHECK: %[[#elt3:]] = OpCompositeExtract %[[#int_32]] %[[#mul_vec]] 3
-; CHECK: %[[#sum2:]] = OpIAdd %[[#int_32]] %[[#sum1]] %[[#elt3]]
+
+; CHECK-DOT: %[[#dot:]] = OpSDot %[[#int_32]] %[[#arg0]] %[[#arg1]]
+
+; CHECK-EXP: %[[#mul_vec:]] = OpIMul %[[#vec4_int_32]] %[[#arg0]] %[[#arg1]]
+; CHECK-EXP: %[[#elt0:]] = OpCompositeExtract %[[#int_32]] %[[#mul_vec]] 0
+; CHECK-EXP: %[[#elt1:]] = OpCompositeExtract %[[#int_32]] %[[#mul_vec]] 1
+; CHECK-EXP: %[[#sum0:]] = OpIAdd %[[#int_32]] %[[#elt0]] %[[#elt1]]
+; CHECK-EXP: %[[#elt2:]] = OpCompositeExtract %[[#int_32]] %[[#mul_vec]] 2
+; CHECK-EXP: %[[#sum1:]] = OpIAdd %[[#int_32]] %[[#sum0]] %[[#elt2]]
+; CHECK-EXP: %[[#elt3:]] = OpCompositeExtract %[[#int_32]] %[[#mul_vec]] 3
+; CHECK-EXP: %[[#sum2:]] = OpIAdd %[[#int_32]] %[[#sum1]] %[[#elt3]]
   %dot = call i32 @llvm.spv.sdot.v4i32(<4 x i32> %a, <4 x i32> %b)
   ret i32 %dot
 }
 
+define noundef i8 @dot_uint8_t4(<4 x i8> noundef %a, <4 x i8> noundef %b) {
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inbelic wrote:

I see, no the packed integers will still be stored as an i32. I am not sure there is an HLSL use-case then. But, I think it is important to have this test-case to ensure that we correctly generate the `DotProductInput4x8Bit` and its implied capabilities.

https://github.com/llvm/llvm-project/pull/115095