[MCParser] Rename confusing variable names

https://reviews.llvm.org/D24047 added `IsAtStartOfStatement` to
MCAsmLexer, while its subclass AsmLexer had a variable of the same name.
The assignment in `UnLex` is unnecessary, which is now removed.

60b403e (2019) named the result
`parseStatement` `Parsed`. `HasError` is a clearer name.

Author: MaskRay

llvm/include/llvm/MC/MCParser/AsmLexer.h

@@ -53,7 +53,7 @@ class AsmLexer {
   const MCAsmInfo &MAI;
 
   bool IsAtStartOfLine = true;
-  bool AtStartOfStatement = true;
+  bool JustConsumedEOL = true;
   bool IsPeeking = false;
   bool EndStatementAtEOF = true;
 
@@ -91,7 +91,7 @@ class AsmLexer {
   const AsmToken &Lex() {
     assert(!CurTok.empty());
     // Mark if we parsing out a EndOfStatement.
-    AtStartOfStatement = CurTok.front().getKind() == AsmToken::EndOfStatement;
+    JustConsumedEOL = CurTok.front().getKind() == AsmToken::EndOfStatement;
     CurTok.erase(CurTok.begin());
     // LexToken may generate multiple tokens via UnLex but will always return
     // the first one. Place returned value at head of CurTok vector.
@@ -103,11 +103,10 @@ class AsmLexer {
   }
 
   void UnLex(AsmToken const &Token) {
-    AtStartOfStatement = false;
     CurTok.insert(CurTok.begin(), Token);
   }
 
-  bool isAtStartOfStatement() { return AtStartOfStatement; }
+  bool justConsumedEOL() { return JustConsumedEOL; }
 
   StringRef LexUntilEndOfStatement();
 

llvm/lib/MC/MCParser/AsmParser.cpp

@@ -981,20 +981,19 @@ bool AsmParser::Run(bool NoInitialTextSection, bool NoFinalize) {
   // While we have input, parse each statement.
   while (Lexer.isNot(AsmToken::Eof)) {
     ParseStatementInfo Info(&AsmStrRewrites);
-    bool Parsed = parseStatement(Info, nullptr);
+    bool HasError = parseStatement(Info, nullptr);
 
     // If we have a Lexer Error we are on an Error Token. Load in Lexer Error
     // for printing ErrMsg via Lex() only if no (presumably better) parser error
     // exists.
-    if (Parsed && !hasPendingError() && Lexer.getTok().is(AsmToken::Error)) {
+    if (HasError && !hasPendingError() && Lexer.getTok().is(AsmToken::Error))
       Lex();
-    }
 
     // parseStatement returned true so may need to emit an error.
     printPendingErrors();
 
     // Skipping to the next line if needed.
-    if (Parsed && !getLexer().isAtStartOfStatement())
+    if (HasError && !getLexer().justConsumedEOL())
       eatToEndOfStatement();
   }
 

llvm/lib/MC/MCParser/MasmParser.cpp

@@ -1100,17 +1100,18 @@ bool MasmParser::expandMacros() {
 const AsmToken &MasmParser::Lex(ExpandKind ExpandNextToken) {
   if (Lexer.getTok().is(AsmToken::Error))
     Error(Lexer.getErrLoc(), Lexer.getErr());
+  bool StartOfStatement = false;
 
   // if it's a end of statement with a comment in it
   if (getTok().is(AsmToken::EndOfStatement)) {
     // if this is a line comment output it.
     if (!getTok().getString().empty() && getTok().getString().front() != '\n' &&
         getTok().getString().front() != '\r' && MAI.preserveAsmComments())
       Out.addExplicitComment(Twine(getTok().getString()));
+    StartOfStatement = true;
   }
 
   const AsmToken *tok = &Lexer.Lex();
-  bool StartOfStatement = Lexer.isAtStartOfStatement();
 
   while (ExpandNextToken == ExpandMacros && tok->is(AsmToken::Identifier)) {
     if (StartOfStatement) {
@@ -1203,20 +1204,19 @@ bool MasmParser::Run(bool NoInitialTextSection, bool NoFinalize) {
       Lex();
 
     ParseStatementInfo Info(&AsmStrRewrites);
-    bool Parsed = parseStatement(Info, nullptr);
+    bool HasError = parseStatement(Info, nullptr);
 
     // If we have a Lexer Error we are on an Error Token. Load in Lexer Error
     // for printing ErrMsg via Lex() only if no (presumably better) parser error
     // exists.
-    if (Parsed && !hasPendingError() && Lexer.getTok().is(AsmToken::Error)) {
+    if (HasError && !hasPendingError() && Lexer.getTok().is(AsmToken::Error))
       Lex();
-    }
 
     // parseStatement returned true so may need to emit an error.
     printPendingErrors();
 
     // Skipping to the next line if needed.
-    if (Parsed && !getLexer().isAtStartOfStatement())
+    if (HasError && !getLexer().justConsumedEOL())
       eatToEndOfStatement();
   }
 
@@ -2802,25 +2802,24 @@ bool MasmParser::handleMacroInvocation(const MCAsmMacro *M, SMLoc NameLoc) {
   SmallVector<AsmRewrite, 4> AsmStrRewrites;
   while (Lexer.isNot(AsmToken::Eof)) {
     ParseStatementInfo Info(&AsmStrRewrites);
-    bool Parsed = parseStatement(Info, nullptr);
+    bool HasError = parseStatement(Info, nullptr);
 
-    if (!Parsed && Info.ExitValue) {
+    if (!HasError && Info.ExitValue) {
       ExitValue = std::move(*Info.ExitValue);
       break;
     }
 
     // If we have a Lexer Error we are on an Error Token. Load in Lexer Error
     // for printing ErrMsg via Lex() only if no (presumably better) parser error
     // exists.
-    if (Parsed && !hasPendingError() && Lexer.getTok().is(AsmToken::Error)) {
+    if (HasError && !hasPendingError() && Lexer.getTok().is(AsmToken::Error))
       Lex();
-    }
 
     // parseStatement returned true so may need to emit an error.
     printPendingErrors();
 
     // Skipping to the next line if needed.
-    if (Parsed && !getLexer().isAtStartOfStatement())
+    if (HasError && !getLexer().justConsumedEOL())
       eatToEndOfStatement();
   }
 

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

@@ -1097,8 +1097,6 @@ class X86AsmParser : public MCTargetAsmParser {
              bool MatchingInlineAsm = false) {
     MCAsmParser &Parser = getParser();
     if (MatchingInlineAsm) {
-      if (!getLexer().isAtStartOfStatement())
-        Parser.eatToEndOfStatement();
       return false;
     }
     return Parser.Error(L, Msg, Range);