llvm-mc: Add MCAsmParser::Parse[Paren]Expression forms which return an MCExpr.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80574 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/MC/MCAsmParser.h b/include/llvm/MC/MCAsmParser.h
index e0a48f1..23c97f5 100644
--- a/include/llvm/MC/MCAsmParser.h
+++ b/include/llvm/MC/MCAsmParser.h
@@ -15,6 +15,7 @@
 namespace llvm {
 class MCAsmLexer;
 class MCContext;
+class MCExpr;
 class MCValue;
 class SMLoc;
 class Twine;
@@ -45,6 +46,21 @@
   /// clients.
   virtual bool Error(SMLoc L, const Twine &Msg) = 0;
 
+  /// ParseExpression - Parse an arbitrary expression.
+  ///
+  /// @param Res - The value of the expression. The result is undefined
+  /// on error.
+  /// @result - False on success.
+  virtual bool ParseExpression(const MCExpr *&Res) = 0;
+
+  /// ParseParenExpression - Parse an arbitrary expression, assuming that an
+  /// initial '(' has already been consumed.
+  ///
+  /// @param Res - The value of the expression. The result is undefined
+  /// on error.
+  /// @result - False on success.
+  virtual bool ParseParenExpression(const MCExpr *&Res) = 0;
+
   /// ParseAbsoluteExpression - Parse an expression which must evaluate to an
   /// absolute value.
   ///
diff --git a/tools/llvm-mc/AsmParser.cpp b/tools/llvm-mc/AsmParser.cpp
index 5d73a9f..78cab38 100644
--- a/tools/llvm-mc/AsmParser.cpp
+++ b/tools/llvm-mc/AsmParser.cpp
@@ -21,6 +21,7 @@
 #include "llvm/MC/MCSectionMachO.h"
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCValue.h"
 #include "llvm/Support/SourceMgr.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetAsmParser.h"
@@ -258,6 +259,13 @@
          ParseBinOpRHS(1, Res);
 }
 
+bool AsmParser::ParseParenExpression(const MCExpr *&Res) {
+  if (ParseParenExpr(Res))
+    return true;
+
+  return false;
+}
+
 bool AsmParser::ParseAbsoluteExpression(int64_t &Res) {
   const MCExpr *Expr;
   
diff --git a/tools/llvm-mc/AsmParser.h b/tools/llvm-mc/AsmParser.h
index b7082b6..2e328d9 100644
--- a/tools/llvm-mc/AsmParser.h
+++ b/tools/llvm-mc/AsmParser.h
@@ -70,6 +70,8 @@
 
   virtual bool ParseExpression(const MCExpr *&Res);
 
+  virtual bool ParseParenExpression(const MCExpr *&Res);
+
   virtual bool ParseAbsoluteExpression(int64_t &Res);
 
   virtual bool ParseRelocatableExpression(MCValue &Res);