[llvm] [llvm][arm] add T1 and T2 assembly options for vlldm and vlstm (PR #83116)

[Tomas Matheson via llvm-commits]

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@@ -91,6 +91,38 @@ void ARMInstPrinter::printInst(const MCInst *MI, uint64_t Address,
   unsigned Opcode = MI->getOpcode();
 
   switch (Opcode) {
+  case ARM::VLLDM: {
+    const MCOperand &Reg = MI->getOperand(0);
+    O << '\t' << "vlldm" << '\t';
+    printRegName(O, Reg.getReg());
+    O << ", "
+      << "{d0 - d15}";
+    return;
+  }
+  case ARM::VLLDM_T2: {
+    const MCOperand &Reg = MI->getOperand(0);
+    O << '\t' << "vlldm" << '\t';
+    printRegName(O, Reg.getReg());
+    O << ", "
+      << "{d0 - d31}";
+    return;
+  }
+  case ARM::VLSTM: {
+    const MCOperand &Reg = MI->getOperand(0);
+    O << '\t' << "vlstm" << '\t';
+    printRegName(O, Reg.getReg());
+    O << ", "
+      << "{d0 - d15}";
+    return;
+  }
+  case ARM::VLSTM_T2: {
+    const MCOperand &Reg = MI->getOperand(0);
+    O << '\t' << "vlstm" << '\t';
+    printRegName(O, Reg.getReg());
+    O << ", "
+      << "{d0 - d31}";
+    return;
+  }
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tmatheson-arm wrote:

I think if you used a non-arbitrary value for the register list operand (which `DecodeRegListOperand` should give you) then you could avoid need for custom printing.

https://github.com/llvm/llvm-project/pull/83116