[llvm] a167976 - [MC] Use ParseStatus in generated AsmParser methods

[Sergei Barannikov via llvm-commits]

Author: Sergei Barannikov
Date: 2023-07-04T22:10:03+03:00
New Revision: a16797699e6f8a90a315d8b895da271854a0888e

URL: https://github.com/llvm/llvm-project/commit/a16797699e6f8a90a315d8b895da271854a0888e
DIFF: https://github.com/llvm/llvm-project/commit/a16797699e6f8a90a315d8b895da271854a0888e.diff

LOG: [MC] Use ParseStatus in generated AsmParser methods

ParseStatus is slightly more convenient to use due to implicit
conversion from bool, which allows to do something like:
```
  return Error(L, "msg");
```
when with MatchOperandResultTy it had to be:
```
  Error(L, "msg");
  return MatchOperand_ParseFail;
```
It also has more appropriate name since parse* methods are not only for
parsing operands.

Reviewed By: kosarev

Differential Revision: https://reviews.llvm.org/D154303

Added: 
    

Modified: 
    llvm/include/llvm/MC/MCParser/MCTargetAsmParser.h
    llvm/utils/TableGen/AsmMatcherEmitter.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/MC/MCParser/MCTargetAsmParser.h b/llvm/include/llvm/MC/MCParser/MCTargetAsmParser.h
index 299f9b055ff779..1d87f0131efcb0 100644
--- a/llvm/include/llvm/MC/MCParser/MCTargetAsmParser.h
+++ b/llvm/include/llvm/MC/MCParser/MCTargetAsmParser.h
@@ -122,6 +122,12 @@ struct ParseInstructionInfo {
     : AsmRewrites(rewrites) {}
 };
 
+enum OperandMatchResultTy {
+  MatchOperand_Success,  // operand matched successfully
+  MatchOperand_NoMatch,  // operand did not match
+  MatchOperand_ParseFail // operand matched but had errors
+};
+
 /// Ternary parse status returned by various parse* methods.
 class ParseStatus {
   enum class StatusTy { Success, Failure, NoMatch } Status;
@@ -146,12 +152,17 @@ class ParseStatus {
   constexpr bool isSuccess() const { return Status == StatusTy::Success; }
   constexpr bool isFailure() const { return Status == StatusTy::Failure; }
   constexpr bool isNoMatch() const { return Status == StatusTy::NoMatch; }
-};
 
-enum OperandMatchResultTy {
-  MatchOperand_Success,  // operand matched successfully
-  MatchOperand_NoMatch,  // operand did not match
-  MatchOperand_ParseFail // operand matched but had errors
+  // Allow implicit conversions to / from OperandMatchResultTy.
+  constexpr ParseStatus(OperandMatchResultTy R)
+      : Status(R == MatchOperand_Success     ? Success
+               : R == MatchOperand_ParseFail ? Failure
+                                             : NoMatch) {}
+  constexpr operator OperandMatchResultTy() const {
+    return isSuccess()   ? MatchOperand_Success
+           : isFailure() ? MatchOperand_ParseFail
+                         : MatchOperand_NoMatch;
+  }
 };
 
 enum class DiagnosticPredicateTy {

diff  --git a/llvm/utils/TableGen/AsmMatcherEmitter.cpp b/llvm/utils/TableGen/AsmMatcherEmitter.cpp
index f6ef5ee1f96027..1c195200a888ca 100644
--- a/llvm/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/llvm/utils/TableGen/AsmMatcherEmitter.cpp
@@ -2927,7 +2927,7 @@ emitCustomOperandParsing(raw_ostream &OS, CodeGenTarget &Target,
 
   // Emit the operand class switch to call the correct custom parser for
   // the found operand class.
-  OS << "OperandMatchResultTy " << Target.getName() << ClassName << "::\n"
+  OS << "ParseStatus " << Target.getName() << ClassName << "::\n"
      << "tryCustomParseOperand(OperandVector"
      << " &Operands,\n                      unsigned MCK) {\n\n"
      << "  switch(MCK) {\n";
@@ -2940,15 +2940,15 @@ emitCustomOperandParsing(raw_ostream &OS, CodeGenTarget &Target,
   }
 
   OS << "  default:\n";
-  OS << "    return MatchOperand_NoMatch;\n";
+  OS << "    return ParseStatus::NoMatch;\n";
   OS << "  }\n";
-  OS << "  return MatchOperand_NoMatch;\n";
+  OS << "  return ParseStatus::NoMatch;\n";
   OS << "}\n\n";
 
   // Emit the static custom operand parser. This code is very similar with
   // the other matcher. Also use MatchResultTy here just in case we go for
   // a better error handling.
-  OS << "OperandMatchResultTy " << Target.getName() << ClassName << "::\n"
+  OS << "ParseStatus " << Target.getName() << ClassName << "::\n"
      << "MatchOperandParserImpl(OperandVector"
      << " &Operands,\n                       StringRef Mnemonic,\n"
      << "                       bool ParseForAllFeatures) {\n";
@@ -2979,7 +2979,7 @@ emitCustomOperandParsing(raw_ostream &OS, CodeGenTarget &Target,
   }
 
   OS << "  if (MnemonicRange.first == MnemonicRange.second)\n";
-  OS << "    return MatchOperand_NoMatch;\n\n";
+  OS << "    return ParseStatus::NoMatch;\n\n";
 
   OS << "  for (const OperandMatchEntry *it = MnemonicRange.first,\n"
      << "       *ie = MnemonicRange.second; it != ie; ++it) {\n";
@@ -3005,14 +3005,13 @@ emitCustomOperandParsing(raw_ostream &OS, CodeGenTarget &Target,
   if (ParserName.empty())
     ParserName = "tryCustomParseOperand";
   OS << "    // call custom parse method to handle the operand\n";
-  OS << "    OperandMatchResultTy Result = " << ParserName
-     << "(Operands, it->Class);\n";
-  OS << "    if (Result != MatchOperand_NoMatch)\n";
+  OS << "    ParseStatus Result = " << ParserName << "(Operands, it->Class);\n";
+  OS << "    if (!Result.isNoMatch())\n";
   OS << "      return Result;\n";
   OS << "  }\n\n";
 
   OS << "  // Okay, we had no match.\n";
-  OS << "  return MatchOperand_NoMatch;\n";
+  OS << "  return ParseStatus::NoMatch;\n";
   OS << "}\n\n";
 }
 
@@ -3308,12 +3307,12 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
 
 
   if (!Info.OperandMatchInfo.empty()) {
-    OS << "  OperandMatchResultTy MatchOperandParserImpl(\n";
+    OS << "  ParseStatus MatchOperandParserImpl(\n";
     OS << "    OperandVector &Operands,\n";
     OS << "    StringRef Mnemonic,\n";
     OS << "    bool ParseForAllFeatures = false);\n";
 
-    OS << "  OperandMatchResultTy tryCustomParseOperand(\n";
+    OS << "  ParseStatus tryCustomParseOperand(\n";
     OS << "    OperandVector &Operands,\n";
     OS << "    unsigned MCK);\n\n";
   }