diff options
Diffstat (limited to 'src/cmd/gc/esc.c')
| -rw-r--r-- | src/cmd/gc/esc.c | 27 |
1 files changed, 25 insertions, 2 deletions
diff --git a/src/cmd/gc/esc.c b/src/cmd/gc/esc.c index a75517813..78624d7cb 100644 --- a/src/cmd/gc/esc.c +++ b/src/cmd/gc/esc.c @@ -442,6 +442,18 @@ esc(EscState *e, Node *n, Node *up) if(n->op == OFOR || n->op == ORANGE) e->loopdepth++; + // type switch variables have no ODCL. + // process type switch as declaration. + // must happen before processing of switch body, + // so before recursion. + if(n->op == OSWITCH && n->ntest && n->ntest->op == OTYPESW) { + for(ll=n->list; ll; ll=ll->next) { // cases + // ll->n->nname is the variable per case + if(ll->n->nname) + ll->n->nname->escloopdepth = e->loopdepth; + } + } + esc(e, n->left, n); esc(e, n->right, n); esc(e, n->ntest, n); @@ -658,13 +670,24 @@ esc(EscState *e, Node *n, Node *up) // current loop depth is an upper bound on actual loop depth // of addressed value. n->escloopdepth = e->loopdepth; - // for &x, use loop depth of x. + // for &x, use loop depth of x if known. + // it should always be known, but if not, be conservative + // and keep the current loop depth. if(n->left->op == ONAME) { switch(n->left->class) { case PAUTO: + if(n->left->escloopdepth != 0) + n->escloopdepth = n->left->escloopdepth; + break; case PPARAM: case PPARAMOUT: - n->escloopdepth = n->left->escloopdepth; + // PPARAM is loop depth 1 always. + // PPARAMOUT is loop depth 0 for writes + // but considered loop depth 1 for address-of, + // so that writing the address of one result + // to another (or the same) result makes the + // first result move to the heap. + n->escloopdepth = 1; break; } } |