Implement .cfi_escape. Patch by Brian Anderson!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147352 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index aac020d..2ccea78 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -301,6 +301,8 @@
       &GenericAsmParser::ParseDirectiveCFIRestoreState>(".cfi_restore_state");
     AddDirectiveHandler<
       &GenericAsmParser::ParseDirectiveCFISameValue>(".cfi_same_value");
+    AddDirectiveHandler<
+      &GenericAsmParser::ParseDirectiveCFIEscape>(".cfi_escape");
 
     // Macro directives.
     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveMacrosOnOff>(
@@ -334,6 +336,7 @@
   bool ParseDirectiveCFIRememberState(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFIRestoreState(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFISameValue(StringRef, SMLoc DirectiveLoc);
+  bool ParseDirectiveCFIEscape(StringRef, SMLoc DirectiveLoc);
 
   bool ParseDirectiveMacrosOnOff(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveMacro(StringRef, SMLoc DirectiveLoc);
@@ -2812,6 +2815,30 @@
   return false;
 }
 
+/// ParseDirectiveCFIEscape
+/// ::= .cfi_escape expression[,...]
+bool GenericAsmParser::ParseDirectiveCFIEscape(StringRef IDVal,
+					       SMLoc DirectiveLoc) {
+  std::string Values;
+  int64_t CurrValue;
+  if (getParser().ParseAbsoluteExpression(CurrValue))
+    return true;
+
+  Values.push_back((uint8_t)CurrValue);
+
+  while (getLexer().is(AsmToken::Comma)) {
+    Lex();
+
+    if (getParser().ParseAbsoluteExpression(CurrValue))
+      return true;
+
+    Values.push_back((uint8_t)CurrValue);
+  }
+
+  getStreamer().EmitCFIEscape(Values);
+  return false;
+}
+
 /// ParseDirectiveMacrosOnOff
 /// ::= .macros_on
 /// ::= .macros_off