fixed op=, ++ and -- on maps (bug060)

R=r
DELTA=22  (21 added, 0 deleted, 1 changed)
OCL=14049
CL=14049

diff --git a/src/cmd/gc/walk.c b/src/cmd/gc/walk.c
index 56d1b01b119403159689bcb1ade2488a97dffb88..ad96e2e2b14a0220afa2953bd67d8ef2d2247343 100644 (file)
--- a/src/cmd/gc/walk.c
+++ b/src/cmd/gc/walk.c
@@ -458,7 +458,13 @@ loop:
                if(top != Etop)
                        goto nottop;
                walktype(n->left, Elv);
-               goto com;
+               l = n->left;
+               if(l->op != OINDEX)
+                       goto com;
+               if(!isptrto(l->left->type, TMAP))
+                       goto com;
+               *n = *mapop(n, top);
+               goto loop;
 
        case OLSH:
        case ORSH:
@@ -1875,6 +1881,21 @@ mapop(Node *n, int top)
                r = n;
                break;
 
+       case OASOP:
+               // rewrite map[index] op= right
+               // into tmpi := index; map[tmpi] = map[tmpi] op right
+
+               t = n->left->left->type->type;
+               a = nod(OXXX, N, N);
+               tempname(a, t->down);                   // tmpi
+               r = nod(OAS, a, n->left->right);        // tmpi := index
+               n->left->right = a;                     // m[tmpi]
+
+               a = nod(OXXX, N, N);
+               *a = *n->left;                          // copy of map[tmpi]
+               a = nod(n->etype, a, n->right);         // m[tmpi] op right
+               a = nod(OAS, n->left, a);               // map[tmpi] = map[tmpi] op right
+               r = nod(OLIST, r, a);
        }
        return r;