[clang] [llvm] [HLSL][DXIL][SPIRV] Create llvm dot intrinsic and use for HLSL (PR #102872)

[Greg Roth via cfe-commits]

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@@ -1057,6 +1057,27 @@ def G_FTANH : GenericInstruction {
   let hasSideEffects = false;
 }
 
+/// Floating point vector dot product
+def G_FDOTPROD : GenericInstruction {
+  let OutOperandList = (outs type0:$dst);
+  let InOperandList = (ins type0:$src1, type0:$src2);
+  let hasSideEffects = false;
+}
+
+/// Signed integer vector dot product
+def G_SDOTPROD : GenericInstruction {
+  let OutOperandList = (outs type0:$dst);
+  let InOperandList = (ins type0:$src1, type0:$src2);
+  let hasSideEffects = false;
+}
+
+/// Unsigned integer vector dot product
+def G_UDOTPROD : GenericInstruction {
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pow2clk wrote:

The unweildy names are because G_UDOT and G_SDOT clashed with existing AArch64 intrinsics that take three arguments as one is an accumulated inout parameter. https://github.com/llvm/llvm-project/blob/908c89e04b6019bdb08bb5f1c861af42046db623/llvm/lib/Target/AArch64/AArch64InstrGISel.td#L254

https://github.com/llvm/llvm-project/pull/102872