MC: Constify MCAsmLayout argument to MCExpr::EvaluteAs...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98380 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCExpr.cpp b/lib/MC/MCExpr.cpp
index 0ca2ad8..8d84f53 100644
--- a/lib/MC/MCExpr.cpp
+++ b/lib/MC/MCExpr.cpp
@@ -145,7 +145,7 @@
 
 /* *** */
 
-bool MCExpr::EvaluateAsAbsolute(int64_t &Res, MCAsmLayout *Layout) const {
+bool MCExpr::EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout *Layout) const {
   MCValue Value;
   
   if (!EvaluateAsRelocatable(Value, Layout) || !Value.isAbsolute())
@@ -177,7 +177,8 @@
   return true;
 }
 
-bool MCExpr::EvaluateAsRelocatable(MCValue &Res, MCAsmLayout *Layout) const {
+bool MCExpr::EvaluateAsRelocatable(MCValue &Res,
+                                   const MCAsmLayout *Layout) const {
   switch (getKind()) {
   case Target:
     return cast<MCTargetExpr>(this)->EvaluateAsRelocatableImpl(Res, Layout);