# HG changeset patch
# User Anders Halager <halager@gmail.com>
# Date 1209739111 -7200
# Node ID ad956143dcdc50132d1d2f7d0bb9e921fdbb3e52
# Parent  9171f04dd9ee7fede18861d5787a1afe7c0a69af
Parse and gen for dereferences

diff -r 9171f04dd9ee -r ad956143dcdc ast/Exp.d
--- a/ast/Exp.d	Fri May 02 15:48:57 2008 +0200
+++ b/ast/Exp.d	Fri May 02 16:38:31 2008 +0200
@@ -15,6 +15,7 @@
 {
     Binary,
     Negate,
+    Deref,
     IntegerLit,
     MemberReference,
     ArrayReference,
@@ -210,6 +211,26 @@
         super(ExpType.Negate);
         this.exp = exp;
     }
+
+    Exp simplify()
+    {
+        exp = exp.simplify;
+        return this;
+    }
+
+    override DType type() { return exp.type(); }
+
+    public Exp exp;
+}
+
+class DerefExp : Exp
+{
+    this(Exp exp)
+    {
+        super(ExpType.Deref);
+        this.exp = exp;
+    }
+
     Exp simplify()
     {
         exp = exp.simplify;
diff -r 9171f04dd9ee -r ad956143dcdc gen/CodeGen.d
--- a/gen/CodeGen.d	Fri May 02 15:48:57 2008 +0200
+++ b/gen/CodeGen.d	Fri May 02 16:38:31 2008 +0200
@@ -270,6 +270,10 @@
                 auto negateExp = cast(NegateExp)exp;
                 auto target = genExpression(negateExp.exp);
                 return b.buildNeg(target, "neg");
+            case ExpType.Deref:
+                auto derefExp = cast(DerefExp)exp;
+                auto target = genExpression(derefExp.exp);
+                return b.buildLoad(target, "deref");
             case ExpType.AssignExp:
                 auto assignExp = cast(AssignExp)exp;
                 return buildAssign(assignExp.identifier, assignExp.exp);
diff -r 9171f04dd9ee -r ad956143dcdc parser/Parser.d
--- a/parser/Parser.d	Fri May 02 15:48:57 2008 +0200
+++ b/parser/Parser.d	Fri May 02 16:38:31 2008 +0200
@@ -423,7 +423,11 @@
         int prec;
     }
 
-    static const UnOp[] _unary = [{Tok.Minus, 4}];
+    static const UnOp[] _unary =
+    [
+        {Tok.Minus, 4},
+        {Tok.Star, 4}
+    ];
     UnOp* unary(Tok t)
     {
         foreach (ref op; _unary)
diff -r 9171f04dd9ee -r ad956143dcdc sema/AstAction.d
--- a/sema/AstAction.d	Fri May 02 15:48:57 2008 +0200
+++ b/sema/AstAction.d	Fri May 02 16:38:31 2008 +0200
@@ -128,8 +128,11 @@
     override ExprT actOnUnaryOp(Token op, ExprT operand)
     {
         Exp target = cast(Exp)operand;
-        // can only be -x for now
-        return new NegateExp(target);
+        if (op.type == Tok.Minus)
+            return new NegateExp(target);
+        if (op.type == Tok.Star)
+            return new DerefExp(target);
+        assert(0, "Only valid unary expressions are -x and *x");
     }
 
     override ExprT actOnCallExpr(ExprT fn, ref Token, ExprT[] args, ref Token)
diff -r 9171f04dd9ee -r ad956143dcdc sema/Visitor.d
--- a/sema/Visitor.d	Fri May 02 15:48:57 2008 +0200
+++ b/sema/Visitor.d	Fri May 02 16:38:31 2008 +0200
@@ -70,6 +70,8 @@
                 return visitIntegerLit(cast(IntegerLit)exp);
             case ExpType.Negate:
                 return visitNegateExp(cast(NegateExp)exp);
+            case ExpType.Deref:
+                return visitDerefExp(cast(DerefExp)exp);
             case ExpType.AssignExp:
                 return visitAssignExp(cast(AssignExp)exp);
             case ExpType.CallExp:
@@ -257,6 +259,15 @@
             return ExpT.init;
     }
 
+    ExpT visitDerefExp(DerefExp exp)
+    {
+        visitExp(exp.exp);
+        static if (is(ExpT == void))
+            return;
+        else
+            return ExpT.init;
+    }
+
     ExpT visitIntegerLit(IntegerLit exp)
     {
         static if (is(ExpT == void))
diff -r 9171f04dd9ee -r ad956143dcdc tools/AstPrinter.d
--- a/tools/AstPrinter.d	Fri May 02 15:48:57 2008 +0200
+++ b/tools/AstPrinter.d	Fri May 02 16:38:31 2008 +0200
@@ -120,6 +120,11 @@
                 print("-");
                 printExp(negateExp.exp);
                 break;
+            case ExpType.Deref:
+                auto derefExp = cast(DerefExp)exp;
+                print("*");
+                printExp(derefExp.exp);
+                break;
             case ExpType.AssignExp:
                 auto assignExp = cast(AssignExp)exp;
                 printExp(assignExp.identifier);