xref: /aosp_15_r20/external/capstone/contrib/sysz_update/0004-capstone-generate-GenDisassemblerTables.inc.patch (revision 9a0e4156d50a75a99ec4f1653a0e9602a5d45c18)

From 29da4c6929679b8ac4019767ab4ebcd83c9894b4 Mon Sep 17 00:00:00 2001
From: mephi42 <[email protected]>
Date: Tue, 7 Aug 2018 18:20:17 +0200
Subject: [PATCH 4/7] capstone: generate *GenDisassemblerTables.inc

---
 utils/TableGen/DisassemblerEmitter.cpp    |  12 +-
 utils/TableGen/FixedLenDecoderEmitter.cpp | 248 ++++++++++++++++++++--
 2 files changed, 239 insertions(+), 21 deletions(-)

diff --git a/utils/TableGen/DisassemblerEmitter.cpp b/utils/TableGen/DisassemblerEmitter.cpp
index b99a0a973a2..2ac6d89645c 100644
--- a/utils/TableGen/DisassemblerEmitter.cpp
+++ b/utils/TableGen/DisassemblerEmitter.cpp
@@ -106,6 +106,11 @@ extern void EmitFixedLenDecoder(RecordKeeper &RK, raw_ostream &OS,
 void EmitDisassembler(RecordKeeper &Records, raw_ostream &OS) {
   CodeGenTarget Target(Records);
   emitSourceFileHeader(" * " + Target.getName().str() + " Disassembler", OS);
+#ifdef CAPSTONE
+  OS << "/* Capstone Disassembly Engine */\n"
+        "/* By Nguyen Anh Quynh <[email protected]>, 2013-2015 */\n"
+        "\n";
+#endif

   // X86 uses a custom disassembler.
   if (Target.getName() == "X86") {
@@ -150,7 +155,12 @@ void EmitDisassembler(RecordKeeper &Records, raw_ostream &OS) {
   }

   EmitFixedLenDecoder(Records, OS, Target.getName(),
-                      "if (", " == MCDisassembler::Fail)",
+                      "if (",
+#ifdef CAPSTONE
+                      " == MCDisassembler_Fail)",
+#else
+                      " == MCDisassembler::Fail)",
+#endif
                       "MCDisassembler::Success", "MCDisassembler::Fail", "");
 }

diff --git a/utils/TableGen/FixedLenDecoderEmitter.cpp b/utils/TableGen/FixedLenDecoderEmitter.cpp
index fcecc764d44..36845d960d8 100644
--- a/utils/TableGen/FixedLenDecoderEmitter.cpp
+++ b/utils/TableGen/FixedLenDecoderEmitter.cpp
@@ -730,7 +730,13 @@ void FixedLenDecoderEmitter::emitTable(formatted_raw_ostream &OS,
       ++I;
       unsigned Start = *I++;
       unsigned Len = *I++;
-      OS.indent(Indentation) << "MCD::OPC_ExtractField, " << Start << ", "
+      OS.indent(Indentation)
+#ifdef CAPSTONE
+        << "MCD_OPC_ExtractField"
+#else
+        << "MCD::OPC_ExtractField"
+#endif
+        << ", " << Start << ", "
         << Len << ",  // Inst{";
       if (Len > 1)
         OS << (Start + Len - 1) << "-";
@@ -739,7 +745,13 @@ void FixedLenDecoderEmitter::emitTable(formatted_raw_ostream &OS,
     }
     case MCD::OPC_FilterValue: {
       ++I;
-      OS.indent(Indentation) << "MCD::OPC_FilterValue, ";
+      OS.indent(Indentation)
+#ifdef CAPSTONE
+        << "MCD_OPC_FilterValue"
+#else
+        << "MCD::OPC_FilterValue"
+#endif
+        << ", ";
       // The filter value is ULEB128 encoded.
       while (*I >= 128)
         OS << (unsigned)*I++ << ", ";
@@ -759,7 +771,13 @@ void FixedLenDecoderEmitter::emitTable(formatted_raw_ostream &OS,
       ++I;
       unsigned Start = *I++;
       unsigned Len = *I++;
-      OS.indent(Indentation) << "MCD::OPC_CheckField, " << Start << ", "
+      OS.indent(Indentation)
+#ifdef CAPSTONE
+        << "MCD_OPC_CheckField"
+#else
+        << "MCD::OPC_CheckField"
+#endif
+        << ", " << Start << ", "
         << Len << ", ";// << Val << ", " << NumToSkip << ",\n";
       // ULEB128 encoded field value.
       for (; *I >= 128; ++I)
@@ -777,7 +795,13 @@ void FixedLenDecoderEmitter::emitTable(formatted_raw_ostream &OS,
     }
     case MCD::OPC_CheckPredicate: {
       ++I;
-      OS.indent(Indentation) << "MCD::OPC_CheckPredicate, ";
+      OS.indent(Indentation)
+#ifdef CAPSTONE
+        << "MCD_OPC_CheckPredicate"
+#else
+        << "MCD::OPC_CheckPredicate"
+#endif
+        << ", ";
       for (; *I >= 128; ++I)
         OS << (unsigned)*I << ", ";
       OS << (unsigned)*I++ << ", ";
@@ -803,7 +827,13 @@ void FixedLenDecoderEmitter::emitTable(formatted_raw_ostream &OS,
                && "ULEB128 value too large!");
       // Decode the Opcode value.
       unsigned Opc = decodeULEB128(Buffer);
-      OS.indent(Indentation) << "MCD::OPC_" << (IsTry ? "Try" : "")
+      OS.indent(Indentation)
+#ifdef CAPSTONE
+        << "MCD_OPC_"
+#else
+        << "MCD::OPC_"
+#endif
+        << (IsTry ? "Try" : "")
         << "Decode, ";
       for (p = Buffer; *p >= 128; ++p)
         OS << (unsigned)*p << ", ";
@@ -837,7 +867,12 @@ void FixedLenDecoderEmitter::emitTable(formatted_raw_ostream &OS,
     }
     case MCD::OPC_SoftFail: {
       ++I;
-      OS.indent(Indentation) << "MCD::OPC_SoftFail";
+      OS.indent(Indentation)
+#ifdef CAPSTONE
+        << "MCD_OPC_SoftFail";
+#else
+        << "MCD::OPC_SoftFail";
+#endif
       // Positive mask
       uint64_t Value = 0;
       unsigned Shift = 0;
@@ -869,7 +904,13 @@ void FixedLenDecoderEmitter::emitTable(formatted_raw_ostream &OS,
     }
     case MCD::OPC_Fail: {
       ++I;
-      OS.indent(Indentation) << "MCD::OPC_Fail,\n";
+      OS.indent(Indentation)
+#ifdef CAPSTONE
+        << "MCD_OPC_Fail"
+#else
+        << "MCD::OPC_Fail"
+#endif
+        << ",\n";
       break;
     }
     }
@@ -884,23 +925,46 @@ void FixedLenDecoderEmitter::emitTable(formatted_raw_ostream &OS,
 void FixedLenDecoderEmitter::
 emitPredicateFunction(formatted_raw_ostream &OS, PredicateSet &Predicates,
                       unsigned Indentation) const {
+#ifdef CAPSTONE
+  OS.indent(Indentation) << "static bool getbool(uint64_t b)\n";
+  OS.indent(Indentation) << "{\n";
+  OS.indent(Indentation) << "\treturn b != 0;\n";
+  OS.indent(Indentation) << "}\n\n";
+#endif
+
   // The predicate function is just a big switch statement based on the
   // input predicate index.
   OS.indent(Indentation) << "static bool checkDecoderPredicate(unsigned Idx, "
+#ifdef CAPSTONE
+    << "uint64_t Bits)\n{\n";
+#else
     << "const FeatureBitset& Bits) {\n";
+#endif
   Indentation += 2;
   if (!Predicates.empty()) {
     OS.indent(Indentation) << "switch (Idx) {\n";
-    OS.indent(Indentation) << "default: llvm_unreachable(\"Invalid index!\");\n";
+    OS.indent(Indentation) << "default: "
+#ifdef CAPSTONE
+      << "// "
+#endif
+      << "llvm_unreachable(\"Invalid index!\");\n";
     unsigned Index = 0;
     for (const auto &Predicate : Predicates) {
       OS.indent(Indentation) << "case " << Index++ << ":\n";
-      OS.indent(Indentation+2) << "return (" << Predicate << ");\n";
+      OS.indent(Indentation+2) << "return "
+#ifdef CAPSTONE
+        << "getbool"
+#endif
+        << "(" << Predicate << ");\n";
     }
     OS.indent(Indentation) << "}\n";
   } else {
     // No case statement to emit
-    OS.indent(Indentation) << "llvm_unreachable(\"Invalid index!\");\n";
+    OS.indent(Indentation)
+#ifdef CAPSTONE
+      << "// "
+#endif
+      << "llvm_unreachable(\"Invalid index!\");\n";
   }
   Indentation -= 2;
   OS.indent(Indentation) << "}\n\n";
@@ -911,23 +975,39 @@ emitDecoderFunction(formatted_raw_ostream &OS, DecoderSet &Decoders,
                     unsigned Indentation) const {
   // The decoder function is just a big switch statement based on the
   // input decoder index.
+#ifdef CAPSTONE
+#define EDF_EOL " \\\n"
+  OS.indent(Indentation) << "#define DecodeToMCInst(fname,fieldname, InsnType) \\\n";
+  OS.indent(Indentation) << "static DecodeStatus fname(DecodeStatus S, unsigned Idx, InsnType insn, MCInst *MI, \\\n";
+  OS.indent(Indentation) << "                uint64_t Address, const void *Decoder) \\\n";
+  OS.indent(Indentation) << "{ \\\n";
+#else
+#define EDF_EOL "\n"
   OS.indent(Indentation) << "template<typename InsnType>\n";
   OS.indent(Indentation) << "static DecodeStatus decodeToMCInst(DecodeStatus S,"
     << " unsigned Idx, InsnType insn, MCInst &MI,\n";
   OS.indent(Indentation) << "                                   uint64_t "
     << "Address, const void *Decoder, bool &DecodeComplete) {\n";
+#endif
   Indentation += 2;
+#ifndef CAPSTONE
   OS.indent(Indentation) << "DecodeComplete = true;\n";
-  OS.indent(Indentation) << "InsnType tmp;\n";
-  OS.indent(Indentation) << "switch (Idx) {\n";
-  OS.indent(Indentation) << "default: llvm_unreachable(\"Invalid index!\");\n";
+#endif
+  OS.indent(Indentation) << "InsnType tmp;" EDF_EOL;
+  OS.indent(Indentation) << "switch (Idx) {" EDF_EOL;
+  OS.indent(Indentation) << "default:"
+#ifndef CAPSTONE
+    << " llvm_unreachable(\"Invalid index!\");\n";
+#else
+    << " \\\n";
+#endif
   unsigned Index = 0;
   for (const auto &Decoder : Decoders) {
-    OS.indent(Indentation) << "case " << Index++ << ":\n";
+    OS.indent(Indentation) << "case " << Index++ << ":" EDF_EOL;
     OS << Decoder;
-    OS.indent(Indentation+2) << "return S;\n";
+    OS.indent(Indentation+2) << "return S;" EDF_EOL;
   }
-  OS.indent(Indentation) << "}\n";
+  OS.indent(Indentation) << "}" EDF_EOL;
   Indentation -= 2;
   OS.indent(Indentation) << "}\n\n";
 }
@@ -1054,16 +1134,21 @@ void FilterChooser::emitBinaryParser(raw_ostream &o, unsigned &Indentation,
   const std::string &Decoder = OpInfo.Decoder;

   if (OpInfo.numFields() != 1)
-    o.indent(Indentation) << "tmp = 0;\n";
+    o.indent(Indentation) << "tmp = 0;" EDF_EOL;

   for (const EncodingField &EF : OpInfo) {
     o.indent(Indentation) << "tmp ";
     if (OpInfo.numFields() != 1) o << '|';
-    o << "= fieldFromInstruction"
+    o << "= "
+#ifdef CAPSTONE
+      << "fieldname"
+#else
+      << "fieldFromInstruction"
+#endif
       << "(insn, " << EF.Base << ", " << EF.Width << ')';
     if (OpInfo.numFields() != 1 || EF.Offset != 0)
       o << " << " << EF.Offset;
-    o << ";\n";
+    o << ";" EDF_EOL;
   }

   if (Decoder != "") {
@@ -1071,8 +1156,12 @@ void FilterChooser::emitBinaryParser(raw_ostream &o, unsigned &Indentation,
     o.indent(Indentation) << Emitter->GuardPrefix << Decoder
       << "(MI, tmp, Address, Decoder)"
       << Emitter->GuardPostfix
+#ifdef CAPSTONE
+      << " return MCDisassembler_Fail; \\\n";
+#else
       << " { " << (OpHasCompleteDecoder ? "" : "DecodeComplete = false; ")
       << "return MCDisassembler::Fail; }\n";
+#endif
   } else {
     OpHasCompleteDecoder = true;
     o.indent(Indentation) << "MI.addOperand(MCOperand::createImm(tmp));\n";
@@ -1091,7 +1180,13 @@ void FilterChooser::emitDecoder(raw_ostream &OS, unsigned Indentation,
         << "(MI, insn, Address, Decoder)"
         << Emitter->GuardPostfix
         << " { " << (HasCompleteDecoder ? "" : "DecodeComplete = false; ")
-        << "return MCDisassembler::Fail; }\n";
+        << "return "
+#ifdef CAPSTONE
+        << "MCDisassembler_Fail"
+#else
+        << "MCDisassembler::Fail"
+#endif
+        << "; }\n";
       break;
     }

@@ -1129,10 +1224,19 @@ unsigned FilterChooser::getDecoderIndex(DecoderSet &Decoders,
 static void emitSinglePredicateMatch(raw_ostream &o, StringRef str,
                                      const std::string &PredicateNamespace) {
   if (str[0] == '!')
+#ifdef CAPSTONE
+    o << "~(Bits & " << PredicateNamespace << "_"
+      << str.slice(1,str.size()) << ")";
+#else
     o << "!Bits[" << PredicateNamespace << "::"
       << str.slice(1,str.size()) << "]";
+#endif
   else
+#ifdef CAPSTONE
+    o << "(Bits & " << PredicateNamespace << "_" << str << ")";
+#else
     o << "Bits[" << PredicateNamespace << "::" << str << "]";
+#endif
 }

 bool FilterChooser::emitPredicateMatch(raw_ostream &o, unsigned &Indentation,
@@ -2047,6 +2151,17 @@ static bool populateInstruction(CodeGenTarget &Target,
 // fieldFromInstruction().
 static void emitFieldFromInstruction(formatted_raw_ostream &OS) {
   OS << "// Helper function for extracting fields from encoded instructions.\n"
+#ifdef CAPSTONE
+     << "#define FieldFromInstruction(fname, InsnType) \\\n"
+     << "static InsnType fname(InsnType insn, unsigned startBit, unsigned numBits) \\\n"
+     << "{ \\\n"
+     << "  InsnType fieldMask; \\\n"
+     << "  if (numBits == sizeof(InsnType)*8) \\\n"
+     << "    fieldMask = (InsnType)(-1LL); \\\n"
+     << "  else \\\n"
+     << "    fieldMask = (((InsnType)1 << numBits) - 1) << startBit; \\\n"
+     << "  return (insn & fieldMask) >> startBit; \\\n"
+#else
      << "template<typename InsnType>\n"
    << "static InsnType fieldFromInstruction(InsnType insn, unsigned startBit,\n"
      << "                                     unsigned numBits) {\n"
@@ -2058,12 +2173,92 @@ static void emitFieldFromInstruction(formatted_raw_ostream &OS) {
      << "    else\n"
      << "      fieldMask = (((InsnType)1 << numBits) - 1) << startBit;\n"
      << "    return (insn & fieldMask) >> startBit;\n"
+#endif
      << "}\n\n";
 }

 // emitDecodeInstruction - Emit the templated helper function
 // decodeInstruction().
 static void emitDecodeInstruction(formatted_raw_ostream &OS) {
+#ifdef CAPSTONE
+  OS << "#define DecodeInstruction(fname, fieldname, decoder, InsnType) \\\n"
+     << "static DecodeStatus fname(const uint8_t DecodeTable[], MCInst *MI, \\\n"
+     << "           InsnType insn, uint64_t Address, const MCRegisterInfo *MRI, int feature) \\\n"
+     << "{ \\\n"
+     << "  uint64_t Bits = getFeatureBits(feature); \\\n"
+     << "  const uint8_t *Ptr = DecodeTable; \\\n"
+     << "  uint32_t CurFieldValue = 0, ExpectedValue; \\\n"
+     << "  DecodeStatus S = MCDisassembler_Success; \\\n"
+     << "  unsigned Start, Len, NumToSkip, PIdx, Opc, DecodeIdx; \\\n"
+     << "  InsnType Val, FieldValue, PositiveMask, NegativeMask; \\\n"
+     << "  bool Pred, Fail; \\\n"
+     << "  for (;;) { \\\n"
+     << "    switch (*Ptr) { \\\n"
+     << "    default: \\\n"
+     << "      return MCDisassembler_Fail; \\\n"
+     << "    case MCD_OPC_ExtractField: { \\\n"
+     << "      Start = *++Ptr; \\\n"
+     << "      Len = *++Ptr; \\\n"
+     << "      ++Ptr; \\\n"
+     << "      CurFieldValue = (uint32_t)fieldname(insn, Start, Len); \\\n"
+     << "      break; \\\n"
+     << "    } \\\n"
+     << "    case MCD_OPC_FilterValue: { \\\n"
+     << "      Val = (InsnType)decodeULEB128(++Ptr, &Len); \\\n"
+     << "      Ptr += Len; \\\n"
+     << "      NumToSkip = *Ptr++; \\\n"
+     << "      NumToSkip |= (*Ptr++) << 8; \\\n"
+     << "      if (Val != CurFieldValue) \\\n"
+     << "        Ptr += NumToSkip; \\\n"
+     << "      break; \\\n"
+     << "    } \\\n"
+     << "    case MCD_OPC_CheckField: { \\\n"
+     << "      Start = *++Ptr; \\\n"
+     << "      Len = *++Ptr; \\\n"
+     << "      FieldValue = fieldname(insn, Start, Len); \\\n"
+     << "      ExpectedValue = (uint32_t)decodeULEB128(++Ptr, &Len); \\\n"
+     << "      Ptr += Len; \\\n"
+     << "      NumToSkip = *Ptr++; \\\n"
+     << "      NumToSkip |= (*Ptr++) << 8; \\\n"
+     << "      if (ExpectedValue != FieldValue) \\\n"
+     << "        Ptr += NumToSkip; \\\n"
+     << "      break; \\\n"
+     << "    } \\\n"
+     << "    case MCD_OPC_CheckPredicate: { \\\n"
+     << "      PIdx = (uint32_t)decodeULEB128(++Ptr, &Len); \\\n"
+     << "      Ptr += Len; \\\n"
+     << "      NumToSkip = *Ptr++; \\\n"
+     << "      NumToSkip |= (*Ptr++) << 8; \\\n"
+     << "      Pred = checkDecoderPredicate(PIdx, Bits); \\\n"
+     << "      if (!Pred) \\\n"
+     << "        Ptr += NumToSkip; \\\n"
+     << "      (void)Pred; \\\n"
+     << "      break; \\\n"
+     << "    } \\\n"
+     << "    case MCD_OPC_Decode: { \\\n"
+     << "      Opc = (unsigned)decodeULEB128(++Ptr, &Len); \\\n"
+     << "      Ptr += Len; \\\n"
+     << "      DecodeIdx = (unsigned)decodeULEB128(Ptr, &Len); \\\n"
+     << "      Ptr += Len; \\\n"
+     << "      MCInst_setOpcode(MI, Opc); \\\n"
+     << "      return decoder(S, DecodeIdx, insn, MI, Address, MRI); \\\n"
+     << "    } \\\n"
+     << "    case MCD_OPC_SoftFail: { \\\n"
+     << "      PositiveMask = (InsnType)decodeULEB128(++Ptr, &Len); \\\n"
+     << "      Ptr += Len; \\\n"
+     << "      NegativeMask = (InsnType)decodeULEB128(Ptr, &Len); \\\n"
+     << "      Ptr += Len; \\\n"
+     << "      Fail = (insn & PositiveMask) || (~insn & NegativeMask); \\\n"
+     << "      if (Fail) \\\n"
+     << "        S = MCDisassembler_SoftFail; \\\n"
+     << "      break; \\\n"
+     << "    } \\\n"
+     << "    case MCD_OPC_Fail: { \\\n"
+     << "      return MCDisassembler_Fail; \\\n"
+     << "    } \\\n"
+     << "    } \\\n"
+     << "  } \\\n"
+#else
   OS << "template<typename InsnType>\n"
      << "static DecodeStatus decodeInstruction(const uint8_t DecodeTable[], "
         "MCInst &MI,\n"
@@ -2240,12 +2435,18 @@ static void emitDecodeInstruction(formatted_raw_ostream &OS) {
      << "  }\n"
      << "  llvm_unreachable(\"bogosity detected in disassembler state "
         "machine!\");\n"
+#endif
      << "}\n\n";
 }

 // Emits disassembler code for instruction decoding.
 void FixedLenDecoderEmitter::run(raw_ostream &o) {
   formatted_raw_ostream OS(o);
+#ifdef CAPSTONE
+  OS << "#include \"../../MCInst.h\"\n";
+  OS << "#include \"../../LEB128.h\"\n";
+  OS << "\n";
+#else
   OS << "#include \"llvm/MC/MCInst.h\"\n";
   OS << "#include \"llvm/Support/Debug.h\"\n";
   OS << "#include \"llvm/Support/DataTypes.h\"\n";
@@ -2254,6 +2455,7 @@ void FixedLenDecoderEmitter::run(raw_ostream &o) {
   OS << "#include <assert.h>\n";
   OS << '\n';
   OS << "namespace llvm {\n\n";
+#endif

   emitFieldFromInstruction(OS);

@@ -2322,7 +2524,13 @@ void FixedLenDecoderEmitter::run(raw_ostream &o) {
   // Emit the main entry point for the decoder, decodeInstruction().
   emitDecodeInstruction(OS);

+#ifdef CAPSTONE
+  OS << "FieldFromInstruction(fieldFromInstruction, uint64_t)\n";
+  OS << "DecodeToMCInst(decodeToMCInst, fieldFromInstruction, uint64_t)\n";
+  OS << "DecodeInstruction(decodeInstruction, fieldFromInstruction, decodeToMCInst, uint64_t)\n";
+#else
   OS << "\n} // End llvm namespace\n";
+#endif
 }

 namespace llvm {
--
2.19.1