Added llvm-mc support for parsing the .lsym directive.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75685 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/MC/MCStreamer.h

@@ -126,6 +126,12 @@ namespace llvm {
     /// @param DescValue - The value to set into the n_desc field.
     virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) = 0;
 
+    /// EmitLocalSymbol - Emit a local symbol of @param Value to @param Symbol.
+    ///
+    /// @param Symbol - The local symbol being created.
+    /// @param Value - The value for the symbol.
+    virtual void EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value) = 0;
+
     /// EmitCommonSymbol - Emit a common or local common symbol of @param Size
     /// with the @param Pow2Alignment if non-zero.
     ///

lib/MC/MCAsmStreamer.cpp

@@ -47,6 +47,8 @@ namespace {
 
     virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
 
+    virtual void EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value);
+
     virtual void EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
                                   unsigned Pow2Alignment, bool IsLocal);
 
@@ -172,6 +174,10 @@ void MCAsmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
   OS << ".desc" << ' ' << Symbol->getName() << ',' << DescValue << '\n';
 }
 
+void MCAsmStreamer::EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value) {
+  OS << ".lsym" << ' ' << Symbol->getName() << ',' << Value << '\n';
+}
+
 void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
                                      unsigned Pow2Alignment, bool IsLocal) {
   if (IsLocal)

test/MC/AsmParser/directive_lsym.s

@@ -0,0 +1,8 @@
+# RUN: llvm-mc %s | FileCheck %s
+
+# CHECK: TEST0:
+# CHECK: .lsym bar,foo
+# CHECK: .lsym baz,3
+TEST0:  
+        .lsym   bar, foo
+        .lsym baz, 2+1

tools/llvm-mc/AsmParser.cpp

@@ -528,6 +528,8 @@ bool AsmParser::ParseStatement() {
       return ParseDirectiveDarwinZerofill();
     if (!strcmp(IDVal, ".desc"))
       return ParseDirectiveDarwinSymbolDesc();
+    if (!strcmp(IDVal, ".lsym"))
+      return ParseDirectiveDarwinLsym();
 
     if (!strcmp(IDVal, ".subsections_via_symbols"))
       return ParseDirectiveDarwinSubsectionsViaSymbols();
@@ -1126,3 +1128,33 @@ bool AsmParser::ParseDirectiveAbort() {
 
   return false;
 }
+
+/// ParseDirectiveLsym
+///  ::= .lsym identifier , expression
+bool AsmParser::ParseDirectiveDarwinLsym() {
+  if (Lexer.isNot(asmtok::Identifier))
+    return TokError("expected identifier in directive");
+  
+  // handle the identifier as the key symbol.
+  SMLoc IDLoc = Lexer.getLoc();
+  MCSymbol *Sym = Ctx.GetOrCreateSymbol(Lexer.getCurStrVal());
+  Lexer.Lex();
+
+  if (Lexer.isNot(asmtok::Comma))
+    return TokError("unexpected token in '.lsym' directive");
+  Lexer.Lex();
+
+  MCValue Expr;
+  if (ParseRelocatableExpression(Expr))
+    return true;
+
+  if (Lexer.isNot(asmtok::EndOfStatement))
+    return TokError("unexpected token in '.lsym' directive");
+  
+  Lexer.Lex();
+
+  // Create the Sym with the value of the Expr
+  Out.EmitLocalSymbol(Sym, Expr);
+
+  return false;
+}

tools/llvm-mc/AsmParser.h

@@ -110,6 +110,7 @@ private:
   /// accepts a single symbol (which should be a label or an external).
   bool ParseDirectiveSymbolAttribute(MCStreamer::SymbolAttr Attr);
   bool ParseDirectiveDarwinSymbolDesc(); // Darwin specific ".desc"
+  bool ParseDirectiveDarwinLsym(); // Darwin specific ".lsym"
 
   bool ParseDirectiveComm(bool IsLocal); // ".comm" and ".lcomm"
   bool ParseDirectiveDarwinZerofill(); // Darwin specific ".zerofill"