diff options
Diffstat (limited to 'src/cmd/gc/subr.c')
| -rw-r--r-- | src/cmd/gc/subr.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/src/cmd/gc/subr.c b/src/cmd/gc/subr.c index 819ebd51c..e65ce5551 100644 --- a/src/cmd/gc/subr.c +++ b/src/cmd/gc/subr.c @@ -2346,7 +2346,7 @@ staticname(Type *t) } /* - * return side effect-free n, appending side effects to init. + * return side effect-free, assignable n, appending side effects to init. */ Node* saferef(Node *n, NodeList **init) @@ -2387,6 +2387,33 @@ saferef(Node *n, NodeList **init) return N; } +/* + * return side effect-free n, appending side effects to init. + */ +Node* +safeval(Node *n, NodeList **init) +{ + Node *l; + Node *r; + Node *a; + + // is this a local variable or a dot of a local variable? + for(l=n; l->op == ODOT; l=l->left) + if(l->left->type != T && isptr[l->left->type->etype]) + goto copy; + if(l->op == ONAME && (l->class == PAUTO || l->class == PPARAM)) + return n; + +copy: + l = nod(OXXX, N, N); + tempname(l, n->type); + a = nod(OAS, l, n); + typecheck(&a, Etop); + walkexpr(&a, init); + *init = list(*init, a); + return l; +} + void setmaxarg(Type *t) { |