[ms-inline asm] Add a new function, GetMCInstOperandNum, to the

AsmMatcherEmitter.  This function maps inline assembly operands to MCInst
operands.

For example, '__asm mov j, eax' is represented by the follow MCInst:

<MCInst 1460 <MCOperand Reg:0> <MCOperand Imm:1> <MCOperand Reg:0> 
             <MCOperand Expr:(j)> <MCOperand Reg:0> <MCOperand Reg:43>>

The first 5 MCInst operands are a result of j matching as a memory operand
consisting of a BaseReg (Reg:0), MemScale (Imm:1), MemIndexReg(Reg:0), 
Expr (Expr:(j), and a MemSegReg (Reg:0).  The 6th MCInst operand represents
the eax register (Reg:43).

This translation is necessary to determine the Input and Output Exprs.  If a
single asm operand maps to multiple MCInst operands, the index of the first
MCInst operand is returned.  Ideally, it would return the operand we really
care out (i.e., the Expr:(j) in this case), but I haven't found an easy way
of doing this yet.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162920 91177308-0d34-0410-b5e6-96231b3b80d8

utils/TableGen/AsmMatcherEmitter.cpp

@@ -1697,6 +1697,26 @@ static void emitConvertToMCInst(CodeGenTarget &Target, StringRef ClassName,
         << "      Inst.addOperand(Inst.getOperand(*(p + 1)));\n"
         << "      break;\n";
 
+  std::string OperandFnBody;
+  raw_string_ostream OpOS(OperandFnBody);
+  // Start the operand number lookup function.
+  OpOS << "bool " << Target.getName() << ClassName << "::\n"
+       << "GetMCInstOperandNum(unsigned Kind, MCInst &Inst,\n"
+       << "                 const SmallVectorImpl<MCParsedAsmOperand*> &Operands,"
+       << "\n                 unsigned OperandNum, unsigned &MCOperandNum) {\n"
+       << "  if (Kind >= CVT_NUM_SIGNATURES) return false;\n"
+       << "  MCOperandNum = 0;\n"
+       << "  uint8_t *Converter = ConversionTable[Kind];\n"
+       << "  for (uint8_t *p = Converter; *p; p+= 2) {\n"
+       << "    if (*(p + 1) > OperandNum) continue;\n"
+       << "    switch (*p) {\n"
+       << "    default: llvm_unreachable(\"invalid conversion entry!\");\n"
+       << "    case CVT_Reg:\n"
+       << "      ++MCOperandNum;\n"
+       << "      break;\n"
+       << "    case CVT_Tied:\n"
+       << "      //Inst.getOperand(*(p + 1)));\n"
+       << "      break;\n";
 
   // Pre-populate the operand conversion kinds with the standard always
   // available entries.
@@ -1734,6 +1754,7 @@ static void emitConvertToMCInst(CodeGenTarget &Target, StringRef ClassName,
             << "      return " << AsmMatchConverter
             << "(Inst, Opcode, Operands);\n";
 
+      // FIXME: Handle the operand number lookup for custom match functions.
       continue;
     }
 
@@ -1787,9 +1808,13 @@ static void emitConvertToMCInst(CodeGenTarget &Target, StringRef ClassName,
               << Op.Class->RenderMethod << "(Inst, " << OpInfo.MINumOperands
               << ");\n"
               << "      break;\n";
+
+        // Add a handler for the operand number lookup.
+        OpOS << "    case " << Name << ":\n"
+             << "      MCOperandNum += " << OpInfo.MINumOperands << ";\n"
+             << "      break;\n";
         break;
       }
-
       case MatchableInfo::ResOperand::TiedOperand: {
         // If this operand is tied to a previous one, just copy the MCInst
         // operand from the earlier one.We can only tie single MCOperand values.
@@ -1799,6 +1824,7 @@ static void emitConvertToMCInst(CodeGenTarget &Target, StringRef ClassName,
         Signature += "__Tie" + utostr(TiedOp);
         ConversionRow.push_back(CVT_Tied);
         ConversionRow.push_back(TiedOp);
+        // FIXME: Handle the operand number lookup for tied operands.
         break;
       }
       case MatchableInfo::ResOperand::ImmOperand: {
@@ -1821,6 +1847,9 @@ static void emitConvertToMCInst(CodeGenTarget &Target, StringRef ClassName,
               << "      Inst.addOperand(MCOperand::CreateImm(" << Val << "));\n"
               << "      break;\n";
 
+        OpOS << "    case " << Name << ":\n"
+             << "      ++MCOperandNum;\n"
+             << "      break;\n";
         break;
       }
       case MatchableInfo::ResOperand::RegOperand: {
@@ -1846,6 +1875,10 @@ static void emitConvertToMCInst(CodeGenTarget &Target, StringRef ClassName,
         CvtOS << "    case " << Name << ":\n"
               << "      Inst.addOperand(MCOperand::CreateReg(" << Reg << "));\n"
               << "      break;\n";
+
+        OpOS << "    case " << Name << ":\n"
+             << "      ++MCOperandNum;\n"
+             << "      break;\n";
       }
       }
     }
@@ -1868,6 +1901,9 @@ static void emitConvertToMCInst(CodeGenTarget &Target, StringRef ClassName,
   // Finish up the converter driver function.
   CvtOS << "    }\n  }\n  return true;\n}\n\n";
 
+  // Finish up the operand number lookup function.
+  OpOS << "    }\n  }\n  return true;\n}\n\n";
+
   OS << "namespace {\n";
 
   // Output the operand conversion kind enum.
@@ -1908,6 +1944,8 @@ static void emitConvertToMCInst(CodeGenTarget &Target, StringRef ClassName,
   // Spit out the conversion driver function.
   OS << CvtOS.str();
 
+  // Spit out the operand number lookup function.
+  OS << OpOS.str();
 }
 
 /// emitMatchClassEnumeration - Emit the enumeration for match class kinds.
@@ -2542,6 +2580,10 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
      << "unsigned Opcode,\n"
      << "                       const SmallVectorImpl<MCParsedAsmOperand*> "
      << "&Operands);\n";
+  OS << "  bool GetMCInstOperandNum(unsigned Kind, MCInst &Inst,\n"
+     << "                           const SmallVectorImpl<MCParsedAsmOperand*> "
+     << "&Operands,\n                           unsigned OperandNum, unsigned "
+     << "&MCOperandNum);\n";
   OS << "  bool MnemonicIsValid(StringRef Mnemonic);\n";
   OS << "  unsigned MatchInstructionImpl(\n";
   OS << "    const SmallVectorImpl<MCParsedAsmOperand*> &Operands,\n";