From 9923bc337ee5e5b60737d770281d42a157c24c81 Mon Sep 17 00:00:00 2001 From: DJ Delorie Date: Tue, 7 Dec 2004 20:02:09 +0000 Subject: [PATCH] merge from gcc --- libiberty/ChangeLog | 5 ++++ libiberty/splay-tree.c | 55 ++++++++++++++++++++++++++++++++++++------ 2 files changed, 53 insertions(+), 7 deletions(-) diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog index b053857736..378ee0af0d 100644 --- a/libiberty/ChangeLog +++ b/libiberty/ChangeLog @@ -1,3 +1,8 @@ +2004-12-07 DJ Delorie + + * splay-tree.c (splay_tree_delete_helper): Redesign the logic so + that recursion (and thus large stack space) is not needed. + 2004-11-29 Matt Kraai * pex-unix.c: Fix the spelling of longjmp. diff --git a/libiberty/splay-tree.c b/libiberty/splay-tree.c index fc98db167f..b1410aa300 100644 --- a/libiberty/splay-tree.c +++ b/libiberty/splay-tree.c @@ -59,18 +59,59 @@ splay_tree_delete_helper (sp, node) splay_tree sp; splay_tree_node node; { + splay_tree_node pending = 0; + splay_tree_node active = 0; + if (!node) return; - splay_tree_delete_helper (sp, node->left); - splay_tree_delete_helper (sp, node->right); +#define KDEL(x) if (sp->delete_key) (*sp->delete_key)(x); +#define VDEL(x) if (sp->delete_value) (*sp->delete_value)(x); - if (sp->delete_key) - (*sp->delete_key)(node->key); - if (sp->delete_value) - (*sp->delete_value)(node->value); + KDEL (node->key); + VDEL (node->value); - (*sp->deallocate) ((char*) node, sp->allocate_data); + /* We use the "key" field to hold the "next" pointer. */ + node->key = (splay_tree_key)pending; + pending = (splay_tree_node)node; + + /* Now, keep processing the pending list until there aren't any + more. This is a little more complicated than just recursing, but + it doesn't toast the stack for large trees. */ + + while (pending) + { + active = pending; + pending = 0; + while (active) + { + splay_tree_node temp; + + /* active points to a node which has its key and value + deallocated, we just need to process left and right. */ + + if (active->left) + { + KDEL (active->left->key); + VDEL (active->left->value); + active->left->key = (splay_tree_key)pending; + pending = (splay_tree_node)(active->left); + } + if (active->right) + { + KDEL (active->right->key); + VDEL (active->right->value); + active->right->key = (splay_tree_key)pending; + pending = (splay_tree_node)(active->right); + } + + temp = active; + active = (splay_tree_node)(temp->key); + (*sp->deallocate) ((char*) temp, sp->allocate_data); + } + } +#undef KDEL +#undef VDEL } /* Help splay SP around KEY. PARENT and GRANDPARENT are the parent