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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75545 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/MC/MCStreamer.h

@@ -141,6 +141,13 @@ namespace llvm {
     virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = 0,
                               unsigned Size = 0,unsigned Pow2Alignment = 0) = 0;
 
+    /// AbortAssembly - Stop and don't produce output, printing @param
+    /// AbortReason if non-NULL to indicate the reason the assembly is
+    /// terminated.
+    ///
+    /// @param AbortReason - The reason assembly is terminated, if non-NULL.
+    virtual void AbortAssembly(const char *AbortReason) = 0;
+
     /// @}
     /// @name Generating Data
     /// @{

lib/MC/MCAsmStreamer.cpp

@@ -51,6 +51,8 @@ namespace {
     virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = NULL,
                               unsigned Size = 0, unsigned Pow2Alignment = 0);
 
+    virtual void AbortAssembly(const char *AbortReason = NULL);
+
     virtual void EmitBytes(const char *Data, unsigned Length);
 
     virtual void EmitValue(const MCValue &Value, unsigned Size);
@@ -123,6 +125,14 @@ void MCAsmStreamer::SubsectionsViaSymbols(void) {
   OS << ".subsections_via_symbols\n";
 }
 
+void MCAsmStreamer::AbortAssembly(const char *AbortReason) {
+  OS << ".abort";
+  if (AbortReason != NULL)
+    OS << ' ' << AbortReason;
+  OS << '\n';
+  
+}
+
 void MCAsmStreamer::EmitAssignment(MCSymbol *Symbol, const MCValue &Value,
                                    bool MakeAbsolute) {
   assert(!Symbol->getSection() && "Cannot assign to a label!");

test/MC/AsmParser/directive_abort.s

@@ -0,0 +1,8 @@
+# RUN: llvm-mc %s | FileCheck %s
+
+# CHECK: TEST0:
+# CHECK: .abort "please stop assembing"
+# CHECK: .abort
+TEST0:  
+	.abort       "please stop assembing"
+.abort

tools/llvm-mc/AsmParser.cpp

@@ -529,6 +529,8 @@ bool AsmParser::ParseStatement() {
 
     if (!strcmp(IDVal, ".subsections_via_symbols"))
       return ParseDirectiveDarwinSubsectionsViaSymbols();
+    if (!strcmp(IDVal, ".abort"))
+      return ParseDirectiveAbort();
 
     Warning(IDLoc, "ignoring directive for now");
     EatToEndOfStatement();
@@ -1068,3 +1070,26 @@ bool AsmParser::ParseDirectiveDarwinSubsectionsViaSymbols() {
 
   return false;
 }
+
+/// ParseDirectiveAbort
+///  ::= .abort [ "abort_string" ]
+bool AsmParser::ParseDirectiveAbort() {
+  const char *Str = NULL;
+  if (Lexer.isNot(asmtok::EndOfStatement)) {
+    if (Lexer.isNot(asmtok::String))
+      return TokError("expected string in '.abort' directive");
+    
+    Str = Lexer.getCurStrVal();
+
+    Lexer.Lex();
+  }
+
+  if (Lexer.isNot(asmtok::EndOfStatement))
+    return TokError("unexpected token in '.abort' directive");
+  
+  Lexer.Lex();
+
+  Out.AbortAssembly(Str);
+
+  return false;
+}

tools/llvm-mc/AsmParser.h

@@ -115,6 +115,8 @@ private:
 
   // Darwin specific ".subsections_via_symbols"
   bool ParseDirectiveDarwinSubsectionsViaSymbols();
+
+  bool ParseDirectiveAbort(); // ".abort"
 };
 
 } // end namespace llvm