[clang] [llvm] [RISC-V] Added the mips extension instructions like ehb,ihb and pause etc for for MIPS RV64 P8700. (PR #155747)

[via llvm-commits]

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@@ -99,89 +99,167 @@ class SWPFormat<dag outs, dag ins, string opcodestr, string argstr>
   bits<5> rs2;
   bits<5> rs1;
 
-  let Inst{31-27} = rs3;
-  let Inst{26-25} = imm7{6-5};
-  let Inst{24-20} = rs2;
-  let Inst{19-15} = rs1;
-  let Inst{14-12} = 0b101;
-  let Inst{11-9} = imm7{4-2};
-  let Inst{8-7} = 0b01;
-  let Inst{6-0} = OPC_CUSTOM_0.Value;
+  let Inst{31 - 27} = rs3;
+  let Inst{26 - 25} = imm7{6 - 5};
+  let Inst{24 - 20} = rs2;
+  let Inst{19 - 15} = rs1;
+  let Inst{14 - 12} = 0b101;
+  let Inst{11 - 9} = imm7{4 - 2};
+  let Inst{8 - 7} = 0b01;
+  let Inst{6 - 0} = OPC_CUSTOM_0.Value;
 }
 
 // Prefetch format.
-let hasSideEffects = 0, mayLoad = 1, mayStore = 1 in
-class Mips_prefetch_ri<dag outs, dag ins, string opcodestr, string argstr>
+let hasSideEffects = 0, mayLoad = 1,
+    mayStore = 1 in class
+        Mips_prefetch_ri<dag outs, dag ins, string opcodestr, string argstr>
     : RVInst<outs, ins, opcodestr, argstr, [], InstFormatI> {
   bits<9> imm9;
   bits<5> rs1;
   bits<5> hint;
 
-  let Inst{31-29} = 0b000;
-  let Inst{28-20} = imm9;
-  let Inst{19-15} = rs1;
-  let Inst{14-12} = 0b000;
-  let Inst{11-7} = hint;
-  let Inst{6-0} = OPC_CUSTOM_0.Value;
+  let Inst{31 - 29} = 0b000;
+  let Inst{28 - 20} = imm9;
+  let Inst{19 - 15} = rs1;
+  let Inst{14 - 12} = 0b000;
+  let Inst{11 - 7} = hint;
+  let Inst{6 - 0} = OPC_CUSTOM_0.Value;
+}
+
+// MIPS Ext Insns
+let hasSideEffects = 1, mayLoad = 0,
+    mayStore = 0 in class MIPSExtInst_ri<bits<6> shimm5, string opcodestr>
+    : RVInstIShift<0b00000, 0b001, OPC_OP_IMM, (outs), (ins), opcodestr, ""> {
+  let shamt = shimm5;
+  let rd = 0;
+  let rs1 = 0;
 }
 
 //===----------------------------------------------------------------------===//
 // MIPS extensions
 //===----------------------------------------------------------------------===//
-let Predicates = [HasVendorXMIPSCBOP] ,DecoderNamespace = "Xmipscbop" in {
-  def MIPS_PREF : Mips_prefetch_ri<(outs), (ins GPR:$rs1, uimm9:$imm9, uimm5:$hint),
-                                    "mips.pref", "$hint, ${imm9}(${rs1})">,
-                   Sched<[]>;
+let Predicates = [HasVendorXMIPSCBOP], DecoderNamespace = "XMIPS" in {
+  def MIPS_PREF : Mips_prefetch_ri<(outs),
+                                   (ins GPR
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ukalappa-mips wrote:

same ...anyway ..will rewrite accordingly ..

https://github.com/llvm/llvm-project/pull/155747