[llvm] [LLVM][AArch64] Add register classes for Armv9.6 assembly (PR #111717)

[via llvm-commits]

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@@ -1188,6 +1195,40 @@ def ZPR4b16 : ZPRRegOp<"h", ZPRAsmOp4b16, ElementSizeH, ZPR_4b>;
 def ZPR4b32 : ZPRRegOp<"s", ZPRAsmOp4b32, ElementSizeS, ZPR_4b>;
 def ZPR4b64 : ZPRRegOp<"d", ZPRAsmOp4b64, ElementSizeD, ZPR_4b>;
 
+class ZPRMul2_MinToMaxRegOp<string Suffix, AsmOperandClass C, int  Min, int Max, ElementSizeEnum  Width, RegisterClass RC>
+    : ZPRRegOp<Suffix, C, Width, RC> {
+  let EncoderMethod = "EncodeRegMul_MinMax<2," # Min # ", " # Max # ">";
+  let DecoderMethod = "DecodeZPRMul2_MinMax<" # Min # ", " # Max # ">";
+}
+
+def ZPRMul2AsmOp8_Lo  : ZPRAsmOperand<"VectorB_Lo",  8, "Mul2_Lo">;
+def ZPRMul2AsmOp8_Hi  : ZPRAsmOperand<"VectorB_Hi",  8, "Mul2_Hi">;
+def ZPRMul2AsmOp16_Lo : ZPRAsmOperand<"VectorH_Lo", 16, "Mul2_Lo">;
+def ZPRMul2AsmOp16_Hi : ZPRAsmOperand<"VectorH_Hi", 16, "Mul2_Hi">;
+def ZPRMul2AsmOp32_Lo : ZPRAsmOperand<"VectorS_Lo", 32, "Mul2_Lo">;
+def ZPRMul2AsmOp32_Hi : ZPRAsmOperand<"VectorS_Hi", 32, "Mul2_Hi">;
+def ZPRMul2AsmOp64_Lo : ZPRAsmOperand<"VectorD_Lo", 64, "Mul2_Lo">;
+def ZPRMul2AsmOp64_Hi : ZPRAsmOperand<"VectorD_Hi", 64, "Mul2_Hi">;
+
+def ZPR_K : RegisterClass<"AArch64", [untyped], 128,
+                          (add Z20, Z21, Z22, Z23, Z28, Z29, Z30, Z31)>;
+
+let EncoderMethod = "EncodeZK",
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Lukacma wrote:

Instead of using let ... in statement it might be better to just define Encoder and Decoder Methods inside the def body.

https://github.com/llvm/llvm-project/pull/111717