add a bunch of mod/rm encoding types for fixed mod/rm bytes.

This will work better for the disassembler for modeling things
like lfence/monitor/vmcall etc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95960 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/X86/X86CodeEmitter.cpp

@@ -858,6 +858,27 @@ void Emitter<CodeEmitter>::emitInstruction(const MachineInstr &MI,
                      getX86RegNum(MI.getOperand(CurOp).getReg()));
     ++CurOp;
     break;
+      
+  case X86II::MRM_C1:
+    MCE.emitByte(BaseOpcode);
+    MCE.emitByte(0xC1);
+    break;
+  case X86II::MRM_C8:
+    MCE.emitByte(BaseOpcode);
+    MCE.emitByte(0xC8);
+    break;
+  case X86II::MRM_C9:
+    MCE.emitByte(BaseOpcode);
+    MCE.emitByte(0xC9);
+    break;
+  case X86II::MRM_E8:
+    MCE.emitByte(BaseOpcode);
+    MCE.emitByte(0xE8);
+    break;
+  case X86II::MRM_F0:
+    MCE.emitByte(BaseOpcode);
+    MCE.emitByte(0xF0);
+    break;
   }
 
   if (!Desc->isVariadic() && CurOp != NumOps) {

lib/Target/X86/X86InstrFormats.td

@@ -29,6 +29,11 @@ def MRM0m  : Format<24>; def MRM1m  : Format<25>; def MRM2m  : Format<26>;
 def MRM3m  : Format<27>; def MRM4m  : Format<28>; def MRM5m  : Format<29>;
 def MRM6m  : Format<30>; def MRM7m  : Format<31>;
 def MRMInitReg : Format<32>;
+def MRM_C1 : Format<33>;
+def MRM_C8 : Format<34>;
+def MRM_C9 : Format<35>;
+def MRM_E8 : Format<36>;
+def MRM_F0 : Format<37>;
 
 
 // ImmType - This specifies the immediate type used by an instruction. This is

lib/Target/X86/X86InstrInfo.cpp

@@ -3556,6 +3556,14 @@ static unsigned GetInstSizeWithDesc(const MachineInstr &MI,
       }
     }
     break;
+    
+  case X86II::MRM_C1:
+  case X86II::MRM_C8:
+  case X86II::MRM_C9:
+  case X86II::MRM_E8:
+  case X86II::MRM_F0:
+    FinalSize += 2;
+    break;
   }
 
   case X86II::MRMInitReg:

lib/Target/X86/X86InstrInfo.h

@@ -268,6 +268,13 @@ namespace X86II {
     // MRMInitReg - This form is used for instructions whose source and
     // destinations are the same register.
     MRMInitReg = 32,
+    
+    //// MRM_C1 - A mod/rm byte of exactly 0xC1.
+    MRM_C1 = 33,
+    MRM_C8 = 34,
+    MRM_C9 = 35,
+    MRM_E8 = 36,
+    MRM_F0 = 37,
 
     FormMask       = 63,
 

lib/Target/X86/X86MCCodeEmitter.cpp

@@ -560,6 +560,26 @@ EncodeInstruction(const MCInst &MI, raw_ostream &OS,
                      CurByte, OS, Fixups);
     CurOp += X86AddrNumOperands;
     break;
+  case X86II::MRM_C1:
+    EmitByte(BaseOpcode, CurByte, OS);
+    EmitByte(0xC1, CurByte, OS);
+    break;
+  case X86II::MRM_C8:
+    EmitByte(BaseOpcode, CurByte, OS);
+    EmitByte(0xC8, CurByte, OS);
+    break;
+  case X86II::MRM_C9:
+    EmitByte(BaseOpcode, CurByte, OS);
+    EmitByte(0xC9, CurByte, OS);
+    break;
+  case X86II::MRM_E8:
+    EmitByte(BaseOpcode, CurByte, OS);
+    EmitByte(0xE8, CurByte, OS);
+    break;
+  case X86II::MRM_F0:
+    EmitByte(BaseOpcode, CurByte, OS);
+    EmitByte(0xF0, CurByte, OS);
+    break;
   }
   
   // If there is a remaining operand, it must be a trailing immediate.  Emit it

utils/TableGen/X86RecognizableInstr.cpp

@@ -47,7 +47,8 @@ namespace X86Local {
     D8 = 3, D9 = 4, DA = 5, DB = 6,
     DC = 7, DD = 8, DE = 9, DF = 10,
     XD = 11,  XS = 12,
-    T8 = 13,  TA = 14
+    T8 = 13,  P_TA = 14,
+    P_0F_AE = 16, P_0F_01 = 17
   };
 }
   
@@ -639,7 +640,7 @@ void RecognizableInstr::emitDecodePath(DisassemblerTables &tables) const {
       filter = new DumbFilter();
     opcodeToSet = Opcode;
     break;
-  case X86Local::TA:
+  case X86Local::P_TA:
     opcodeType = THREEBYTE_3A;
     if (needsModRMForDecode(Form))
       filter = new ModFilter(isRegFormat(Form));