Introduce public MCMasmParser interface, and use it for MASM-specific context

Moves the DefaultRetIsFar information from MCContext to MCMasmParser.

Author: ericastor

llvm/include/llvm/MC/MCContext.h

@@ -97,13 +97,9 @@ class MCContext {
     IsDXContainer
   };
 
-  enum DefaultRetType { IsNear, IsFar };
-
 private:
   Environment Env;
 
-  DefaultRetType DefaultRet = IsNear;
-
   /// The name of the Segment where Swift5 Reflection Section data will be
   /// outputted
   StringRef Swift5ReflectionSegmentName;
@@ -398,9 +394,6 @@ class MCContext {
 
   Environment getObjectFileType() const { return Env; }
 
-  DefaultRetType getDefaultRetType() const { return DefaultRet; }
-  void setDefaultRetType(DefaultRetType DR) { DefaultRet = DR; }
-
   const StringRef &getSwift5ReflectionSegmentName() const {
     return Swift5ReflectionSegmentName;
   }

llvm/include/llvm/MC/MCParser/MCMasmParser.h

@@ -0,0 +1,29 @@
+//===- llvm/MC/MasmParser.h - MASM Parser Interface -------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCPARSER_MCMASMPARSER_H
+#define LLVM_MC_MCPARSER_MCMASMPARSER_H
+
+#include "llvm/MC/MCParser/MCAsmParser.h"
+
+namespace llvm {
+
+/// MASM-type assembler parser interface.
+class MCMasmParser : public MCAsmParser {
+public:
+  virtual bool getDefaultRetIsFar() const = 0;
+  virtual void setDefaultRetIsFar(bool IsFar) = 0;
+
+  bool isParsingMasm() const override { return true; }
+
+  static bool classof(const MCAsmParser *AP) { return AP->isParsingMasm(); }
+};
+
+} // end namespace llvm
+
+#endif // LLVM_MC_MCPARSER_MCMASMPARSER_H

llvm/lib/MC/MCParser/COFFMasmParser.cpp

@@ -12,7 +12,9 @@
 #include "llvm/MC/MCAsmMacro.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCParser/MCAsmLexer.h"
+#include "llvm/MC/MCParser/MCAsmParser.h"
 #include "llvm/MC/MCParser/MCAsmParserExtension.h"
+#include "llvm/MC/MCParser/MCMasmParser.h"
 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
 #include "llvm/MC/MCSectionCOFF.h"
 #include "llvm/MC/MCStreamer.h"
@@ -501,9 +503,8 @@ bool COFFMasmParser::parseDirectiveProc(StringRef Directive, SMLoc Loc) {
   if (Proc.Distance == PROC_DISTANCE_FAR)
     Sym->setIsFarProc();
 
-  getContext().setDefaultRetType(Proc.Distance == PROC_DISTANCE_NEAR
-                                     ? MCContext::IsNear
-                                     : MCContext::IsFar);
+  cast<MCMasmParser>(getParser())
+      .setDefaultRetIsFar(Proc.Distance == PROC_DISTANCE_FAR);
 
   if (Proc.IsFramed) {
     getStreamer().emitWinCFIStartProc(Sym, Loc);
@@ -529,11 +530,10 @@ bool COFFMasmParser::parseDirectiveEndProc(StringRef Directive, SMLoc Loc) {
     getStreamer().emitWinCFIEndProc(Loc);
   }
   CurrentProcedures.pop_back();
-  getContext().setDefaultRetType(
-      (CurrentProcedures.empty() ||
-       CurrentProcedures.back().Distance == PROC_DISTANCE_NEAR)
-          ? MCContext::IsNear
-          : MCContext::IsFar);
+  cast<MCMasmParser>(getParser())
+      .setDefaultRetIsFar(!CurrentProcedures.empty() &&
+                          CurrentProcedures.back().Distance ==
+                              PROC_DISTANCE_FAR);
   return false;
 }
 

llvm/lib/MC/MCParser/MasmParser.cpp

@@ -36,6 +36,7 @@
 #include "llvm/MC/MCParser/MCAsmLexer.h"
 #include "llvm/MC/MCParser/MCAsmParser.h"
 #include "llvm/MC/MCParser/MCAsmParserExtension.h"
+#include "llvm/MC/MCParser/MCMasmParser.h"
 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
 #include "llvm/MC/MCRegisterInfo.h"
@@ -65,6 +66,7 @@
 #include <memory>
 #include <optional>
 #include <sstream>
+#include <stdbool.h>
 #include <string>
 #include <tuple>
 #include <utility>
@@ -373,7 +375,7 @@ FieldInitializer &FieldInitializer::operator=(FieldInitializer &&Initializer) {
 /// The concrete assembly parser instance.
 // Note that this is a full MCAsmParser, not an MCAsmParserExtension!
 // It's a peer of AsmParser, not of COFFAsmParser, WasmAsmParser, etc.
-class MasmParser : public MCAsmParser {
+class MasmParser : public MCMasmParser {
 private:
   AsmLexer Lexer;
   MCContext &Ctx;
@@ -456,6 +458,9 @@ class MasmParser : public MCAsmParser {
   /// Are we parsing ms-style inline assembly?
   bool ParsingMSInlineAsm = false;
 
+  /// Is the current default `ret` instruction far?
+  bool DefaultRetIsFar = false;
+
   // Current <...> expression depth.
   unsigned AngleBracketDepth = 0U;
 
@@ -481,6 +486,14 @@ class MasmParser : public MCAsmParser {
     DirectiveKindMap[Directive] = DirectiveKindMap[Alias];
   }
 
+  /// @name MCMasmParser Interface
+  /// {
+
+  bool getDefaultRetIsFar() const override { return DefaultRetIsFar; }
+  void setDefaultRetIsFar(bool IsFar) override { DefaultRetIsFar = IsFar; }
+
+  /// }
+
   /// @name MCAsmParser Interface
   /// {
 
@@ -517,8 +530,6 @@ class MasmParser : public MCAsmParser {
   }
   bool isParsingMSInlineAsm() override { return ParsingMSInlineAsm; }
 
-  bool isParsingMasm() const override { return true; }
-
   bool defineMacro(StringRef Name, StringRef Value) override;
 
   bool lookUpField(StringRef Name, AsmFieldInfo &Info) const override;

llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp

@@ -25,6 +25,7 @@
 #include "llvm/MC/MCInstrInfo.h"
 #include "llvm/MC/MCParser/MCAsmLexer.h"
 #include "llvm/MC/MCParser/MCAsmParser.h"
+#include "llvm/MC/MCParser/MCMasmParser.h"
 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
 #include "llvm/MC/MCRegisterInfo.h"
@@ -3451,7 +3452,7 @@ bool X86AsmParser::parseInstruction(ParseInstructionInfo &Info, StringRef Name,
     // MASM implicitly converts "ret" to "retf" in far procedures; this is
     // reflected in the default return type in the MCContext.
     if (PatchedName == "ret" &&
-        getContext().getDefaultRetType() == MCContext::IsFar)
+        cast<MCMasmParser>(getParser()).getDefaultRetIsFar())
       PatchedName = "retf";
   }