[llvm] [AArch64] Separate PNR into its own Register Class (PR #65306)

[via llvm-commits]

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@@ -909,69 +929,89 @@ class PPRAsmOperand <string name, string RegClass, int Width>: AsmOperandClass {
   let ParserMethod = "tryParseSVEPredicateVector<RegKind::SVEPredicateVector>";
 }
 
-def PPRAsmOpAny : PPRAsmOperand<"PredicateAny", "PPR",  0>;
-def PPRAsmOp8   : PPRAsmOperand<"PredicateB",   "PPR",  8>;
-def PPRAsmOp16  : PPRAsmOperand<"PredicateH",   "PPR", 16>;
-def PPRAsmOp32  : PPRAsmOperand<"PredicateS",   "PPR", 32>;
-def PPRAsmOp64  : PPRAsmOperand<"PredicateD",   "PPR", 64>;
-
-def PPRAny : PPRRegOp<"",  PPRAsmOpAny, ElementSizeNone, PPR>;
-def PPR8   : PPRRegOp<"b", PPRAsmOp8,   ElementSizeB,  PPR>;
-def PPR16  : PPRRegOp<"h", PPRAsmOp16,  ElementSizeH,  PPR>;
-def PPR32  : PPRRegOp<"s", PPRAsmOp32,  ElementSizeS,  PPR>;
-def PPR64  : PPRRegOp<"d", PPRAsmOp64,  ElementSizeD,  PPR>;
-
+def PPRAsmOpAny   : PPRAsmOperand<"PredicateAny",   "PPR",     0>;
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sdesmalen-arm wrote:

This comment is for line 921: `def PPR_p8to15 : PPRClass<8, 15>;`

Is this register class still used somewhere? I thought we  added this for instructions that take predicate-as-counter registers (which are passed in pn8-pn15).

https://github.com/llvm/llvm-project/pull/65306