encapsulate memcpy with constructor

dlang · Nov 27, 2014 · a63721c · a63721c
1 parent 9bb7b32
commit a63721c
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Showing 3 changed files with 23 additions and 16 deletions.
diff --git a/src/constfold.c b/src/constfold.c
@@ -1171,7 +1171,7 @@ UnionExp Cast(Type *type, Type *to, Expression *e1)
     //printf("\te1->type = %s\n", e1->type->toChars());
     if (e1->type->equals(type) && type->equals(to))
     {
-        memcpy(&ue, e1, e1->size);
+        new(&ue) UnionExp(e1);
         return ue;
     }
 
@@ -1205,7 +1205,7 @@ UnionExp Cast(Type *type, Type *to, Expression *e1)
     {
 L1:
         Expression *ex = expType(to, e1);
-        memcpy(&ue, ex, ex->size);
+        new(&ue) UnionExp(ex);
         return ue;
     }
 
@@ -1331,7 +1331,7 @@ UnionExp ArrayLength(Type *type, Expression *e1)
     else if (e1->type->toBasetype()->ty == Tsarray)
     {
         Expression *e = ((TypeSArray *)e1->type->toBasetype())->dim;
-        memcpy(&ue, e, e->size);
+        new(&ue) UnionExp(e);
     }
     else
         new(&ue) CTFEExp(TOKcantexp);
@@ -1382,7 +1382,7 @@ UnionExp Index(Type *type, Expression *e1, Expression *e2)
             if (hasSideEffect(e))
                 new(&ue) CTFEExp(TOKcantexp);
             else
-                memcpy(&ue, e, e->size);
+                new(&ue) UnionExp(e);
         }
         else
             new(&ue) CTFEExp(TOKcantexp);
@@ -1407,7 +1407,7 @@ UnionExp Index(Type *type, Expression *e1, Expression *e2)
                 if (hasSideEffect(e))
                     new(&ue) CTFEExp(TOKcantexp);
                 else
-                    memcpy(&ue, e, e->size);
+                    new(&ue) UnionExp(e);
             }
         }
         else
@@ -1433,7 +1433,7 @@ UnionExp Index(Type *type, Expression *e1, Expression *e2)
                 if (hasSideEffect(e))
                     new(&ue) CTFEExp(TOKcantexp);
                 else
-                    memcpy(&ue, e, e->size);
+                    new(&ue) UnionExp(e);
                 return ue;;
             }
         }
@@ -1704,14 +1704,14 @@ UnionExp Cat(Type *type, Expression *e1, Expression *e2)
             }
             else
             {
-                memcpy(&ue, e1, e1->size);
+                new(&ue) UnionExp(e1);
                 assert(ue.exp()->type);
                 return ue;
             }
         }
         if (type == e2->type)
         {
-            memcpy(&ue, e2, e2->size);
+            new(&ue) UnionExp(e2);
             assert(ue.exp()->type);
             return ue;
         }
@@ -1967,14 +1967,14 @@ UnionExp Cat(Type *type, Expression *e1, Expression *e2)
         }
         else
         {
-            memcpy(&ue, e, e->size);
+            new(&ue) UnionExp(e);
             e = ue.exp();
         }
         if (!e->type->equals(type))
         {
             StringExp *se = (StringExp *)e->copy();
             e = se->castTo(NULL, type);
-            memcpy(&ue, e, e->size);
+            new(&ue) UnionExp(e);
             e = ue.exp();
         }
     }
@@ -2001,7 +2001,7 @@ UnionExp Ptr(Type *type, Expression *e1)
                 Expression *e = se->getField(type, offset);
                 if (e)
                 {
-                    memcpy(&ue, e, e->size);
+                    new(&ue) UnionExp(e);
                     return ue;
                 }
             }

diff --git a/src/ctfeexpr.c b/src/ctfeexpr.c
@@ -309,7 +309,7 @@ UnionExp copyLiteral(Expression *e)
     {
         // Simple value types
         // Keep e1 for DelegateExp and DotVarExp
-        memcpy(&ue, e, e->size);
+        new(&ue) UnionExp(e);
         Expression *r = ue.exp();
         r->type = e->type;
         return ue;
@@ -348,7 +348,7 @@ UnionExp copyLiteral(Expression *e)
     }
     if (e->op == TOKerror)
     {
-        memcpy(&ue, e, e->size);
+        new(&ue) UnionExp(e);
         return ue;
     }
     e->error("Internal Compiler Error: CTFE literal %s", e->toChars());
@@ -375,14 +375,14 @@ UnionExp paintTypeOntoLiteralCopy(Type *type, Expression *lit)
 
     if (lit->type->equals(type))
     {
-        memcpy(&ue, lit, lit->size);
+        new(&ue) UnionExp(lit);
         return ue;
     }
 
     // If it is a cast to inout, retain the original type of the referenced part.
     if (type->hasWild() && type->hasPointers())
     {
-        memcpy(&ue, lit, lit->size);
+        new(&ue) UnionExp(lit);
         ue.exp()->type = type;
         return ue;
     }
@@ -1701,7 +1701,7 @@ UnionExp ctfeCat(Type *type, Expression *e1, Expression *e2)
         ue = Cat(type, e1, e2);
         return ue;
     }
-    memcpy(&ue, e, e->size);
+    new(&ue) UnionExp(e);
     return ue;
 }
 

diff --git a/src/expression.h b/src/expression.h
@@ -1564,6 +1564,13 @@ class PrettyFuncInitExp : public DefaultInitExp
  */
 struct UnionExp
 {
+    UnionExp() { }  // yes, default constructor does nothing
+
+    UnionExp(Expression *e)
+    {
+        memcpy(this, e, e->size);
+    }
+
     /* Extract pointer to Expression
      */
     Expression *exp() { return (Expression *)&u; }