From 82bcbebce43f0227f506d75a5b764b6847041bae Mon Sep 17 00:00:00 2001 From: Ben Cheng Date: Mon, 1 Oct 2012 10:30:31 -0700 Subject: Initial check-in of gcc 4.7.2. Change-Id: I4a2f5a921c21741a0e18bda986d77e5f1bef0365 --- gcc-4.7/libiberty/splay-tree.c | 593 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 593 insertions(+) create mode 100644 gcc-4.7/libiberty/splay-tree.c (limited to 'gcc-4.7/libiberty/splay-tree.c') diff --git a/gcc-4.7/libiberty/splay-tree.c b/gcc-4.7/libiberty/splay-tree.c new file mode 100644 index 000000000..12bfa8bbd --- /dev/null +++ b/gcc-4.7/libiberty/splay-tree.c @@ -0,0 +1,593 @@ +/* A splay-tree datatype. + Copyright (C) 1998, 1999, 2000, 2001, 2009, + 2010, 2011 Free Software Foundation, Inc. + Contributed by Mark Mitchell (mark@markmitchell.com). + +This file is part of GNU CC. + +GNU CC is free software; you can redistribute it and/or modify it +under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU CC is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU CC; see the file COPYING. If not, write to +the Free Software Foundation, 51 Franklin Street - Fifth Floor, +Boston, MA 02110-1301, USA. */ + +/* For an easily readable description of splay-trees, see: + + Lewis, Harry R. and Denenberg, Larry. Data Structures and Their + Algorithms. Harper-Collins, Inc. 1991. */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#ifdef HAVE_STDLIB_H +#include +#endif + +#include + +#include "libiberty.h" +#include "splay-tree.h" + +static void splay_tree_delete_helper (splay_tree, splay_tree_node); +static inline void rotate_left (splay_tree_node *, + splay_tree_node, splay_tree_node); +static inline void rotate_right (splay_tree_node *, + splay_tree_node, splay_tree_node); +static void splay_tree_splay (splay_tree, splay_tree_key); +static int splay_tree_foreach_helper (splay_tree_node, + splay_tree_foreach_fn, void*); + +/* Deallocate NODE (a member of SP), and all its sub-trees. */ + +static void +splay_tree_delete_helper (splay_tree sp, splay_tree_node node) +{ + splay_tree_node pending = 0; + splay_tree_node active = 0; + + if (!node) + return; + +#define KDEL(x) if (sp->delete_key) (*sp->delete_key)(x); +#define VDEL(x) if (sp->delete_value) (*sp->delete_value)(x); + + KDEL (node->key); + VDEL (node->value); + + /* 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 +} + +/* Rotate the edge joining the left child N with its parent P. PP is the + grandparents' pointer to P. */ + +static inline void +rotate_left (splay_tree_node *pp, splay_tree_node p, splay_tree_node n) +{ + splay_tree_node tmp; + tmp = n->right; + n->right = p; + p->left = tmp; + *pp = n; +} + +/* Rotate the edge joining the right child N with its parent P. PP is the + grandparents' pointer to P. */ + +static inline void +rotate_right (splay_tree_node *pp, splay_tree_node p, splay_tree_node n) +{ + splay_tree_node tmp; + tmp = n->left; + n->left = p; + p->right = tmp; + *pp = n; +} + +/* Bottom up splay of key. */ + +static void +splay_tree_splay (splay_tree sp, splay_tree_key key) +{ + if (sp->root == 0) + return; + + do { + int cmp1, cmp2; + splay_tree_node n, c; + + n = sp->root; + cmp1 = (*sp->comp) (key, n->key); + + /* Found. */ + if (cmp1 == 0) + return; + + /* Left or right? If no child, then we're done. */ + if (cmp1 < 0) + c = n->left; + else + c = n->right; + if (!c) + return; + + /* Next one left or right? If found or no child, we're done + after one rotation. */ + cmp2 = (*sp->comp) (key, c->key); + if (cmp2 == 0 + || (cmp2 < 0 && !c->left) + || (cmp2 > 0 && !c->right)) + { + if (cmp1 < 0) + rotate_left (&sp->root, n, c); + else + rotate_right (&sp->root, n, c); + return; + } + + /* Now we have the four cases of double-rotation. */ + if (cmp1 < 0 && cmp2 < 0) + { + rotate_left (&n->left, c, c->left); + rotate_left (&sp->root, n, n->left); + } + else if (cmp1 > 0 && cmp2 > 0) + { + rotate_right (&n->right, c, c->right); + rotate_right (&sp->root, n, n->right); + } + else if (cmp1 < 0 && cmp2 > 0) + { + rotate_right (&n->left, c, c->right); + rotate_left (&sp->root, n, n->left); + } + else if (cmp1 > 0 && cmp2 < 0) + { + rotate_left (&n->right, c, c->left); + rotate_right (&sp->root, n, n->right); + } + } while (1); +} + +/* Call FN, passing it the DATA, for every node below NODE, all of + which are from SP, following an in-order traversal. If FN every + returns a non-zero value, the iteration ceases immediately, and the + value is returned. Otherwise, this function returns 0. */ + +static int +splay_tree_foreach_helper (splay_tree_node node, + splay_tree_foreach_fn fn, void *data) +{ + int val; + splay_tree_node *stack; + int stack_ptr, stack_size; + + /* A non-recursive implementation is used to avoid filling the stack + for large trees. Splay trees are worst case O(n) in the depth of + the tree. */ + +#define INITIAL_STACK_SIZE 100 + stack_size = INITIAL_STACK_SIZE; + stack_ptr = 0; + stack = XNEWVEC (splay_tree_node, stack_size); + val = 0; + + for (;;) + { + while (node != NULL) + { + if (stack_ptr == stack_size) + { + stack_size *= 2; + stack = XRESIZEVEC (splay_tree_node, stack, stack_size); + } + stack[stack_ptr++] = node; + node = node->left; + } + + if (stack_ptr == 0) + break; + + node = stack[--stack_ptr]; + + val = (*fn) (node, data); + if (val) + break; + + node = node->right; + } + + XDELETEVEC (stack); + return val; +} + +/* An allocator and deallocator based on xmalloc. */ +static void * +splay_tree_xmalloc_allocate (int size, void *data ATTRIBUTE_UNUSED) +{ + return (void *) xmalloc (size); +} + +static void +splay_tree_xmalloc_deallocate (void *object, void *data ATTRIBUTE_UNUSED) +{ + free (object); +} + + +/* Allocate a new splay tree, using COMPARE_FN to compare nodes, + DELETE_KEY_FN to deallocate keys, and DELETE_VALUE_FN to deallocate + values. Use xmalloc to allocate the splay tree structure, and any + nodes added. */ + +splay_tree +splay_tree_new (splay_tree_compare_fn compare_fn, + splay_tree_delete_key_fn delete_key_fn, + splay_tree_delete_value_fn delete_value_fn) +{ + return (splay_tree_new_with_allocator + (compare_fn, delete_key_fn, delete_value_fn, + splay_tree_xmalloc_allocate, splay_tree_xmalloc_deallocate, 0)); +} + + +/* Allocate a new splay tree, using COMPARE_FN to compare nodes, + DELETE_KEY_FN to deallocate keys, and DELETE_VALUE_FN to deallocate + values. */ + +splay_tree +splay_tree_new_with_allocator (splay_tree_compare_fn compare_fn, + splay_tree_delete_key_fn delete_key_fn, + splay_tree_delete_value_fn delete_value_fn, + splay_tree_allocate_fn allocate_fn, + splay_tree_deallocate_fn deallocate_fn, + void *allocate_data) +{ + return + splay_tree_new_typed_alloc (compare_fn, delete_key_fn, delete_value_fn, + allocate_fn, allocate_fn, deallocate_fn, + allocate_data); +} + +/* + +@deftypefn Supplemental splay_tree splay_tree_new_with_typed_alloc @ +(splay_tree_compare_fn @var{compare_fn}, @ +splay_tree_delete_key_fn @var{delete_key_fn}, @ +splay_tree_delete_value_fn @var{delete_value_fn}, @ +splay_tree_allocate_fn @var{tree_allocate_fn}, @ +splay_tree_allocate_fn @var{node_allocate_fn}, @ +splay_tree_deallocate_fn @var{deallocate_fn}, @ +void * @var{allocate_data}) + +This function creates a splay tree that uses two different allocators +@var{tree_allocate_fn} and @var{node_allocate_fn} to use for allocating the +tree itself and its nodes respectively. This is useful when variables of +different types need to be allocated with different allocators. + +The splay tree will use @var{compare_fn} to compare nodes, +@var{delete_key_fn} to deallocate keys, and @var{delete_value_fn} to +deallocate values. + +@end deftypefn + +*/ + +splay_tree +splay_tree_new_typed_alloc (splay_tree_compare_fn compare_fn, + splay_tree_delete_key_fn delete_key_fn, + splay_tree_delete_value_fn delete_value_fn, + splay_tree_allocate_fn tree_allocate_fn, + splay_tree_allocate_fn node_allocate_fn, + splay_tree_deallocate_fn deallocate_fn, + void * allocate_data) +{ + splay_tree sp = (splay_tree) (*tree_allocate_fn) + (sizeof (struct splay_tree_s), allocate_data); + + sp->root = 0; + sp->comp = compare_fn; + sp->delete_key = delete_key_fn; + sp->delete_value = delete_value_fn; + sp->allocate = node_allocate_fn; + sp->deallocate = deallocate_fn; + sp->allocate_data = allocate_data; + + return sp; +} + +/* Deallocate SP. */ + +void +splay_tree_delete (splay_tree sp) +{ + splay_tree_delete_helper (sp, sp->root); + (*sp->deallocate) ((char*) sp, sp->allocate_data); +} + +/* Insert a new node (associating KEY with DATA) into SP. If a + previous node with the indicated KEY exists, its data is replaced + with the new value. Returns the new node. */ + +splay_tree_node +splay_tree_insert (splay_tree sp, splay_tree_key key, splay_tree_value value) +{ + int comparison = 0; + + splay_tree_splay (sp, key); + + if (sp->root) + comparison = (*sp->comp)(sp->root->key, key); + + if (sp->root && comparison == 0) + { + /* If the root of the tree already has the indicated KEY, just + replace the value with VALUE. */ + if (sp->delete_value) + (*sp->delete_value)(sp->root->value); + sp->root->value = value; + } + else + { + /* Create a new node, and insert it at the root. */ + splay_tree_node node; + + node = ((splay_tree_node) + (*sp->allocate) (sizeof (struct splay_tree_node_s), + sp->allocate_data)); + node->key = key; + node->value = value; + + if (!sp->root) + node->left = node->right = 0; + else if (comparison < 0) + { + node->left = sp->root; + node->right = node->left->right; + node->left->right = 0; + } + else + { + node->right = sp->root; + node->left = node->right->left; + node->right->left = 0; + } + + sp->root = node; + } + + return sp->root; +} + +/* Remove KEY from SP. It is not an error if it did not exist. */ + +void +splay_tree_remove (splay_tree sp, splay_tree_key key) +{ + splay_tree_splay (sp, key); + + if (sp->root && (*sp->comp) (sp->root->key, key) == 0) + { + splay_tree_node left, right; + + left = sp->root->left; + right = sp->root->right; + + /* Delete the root node itself. */ + if (sp->delete_value) + (*sp->delete_value) (sp->root->value); + (*sp->deallocate) (sp->root, sp->allocate_data); + + /* One of the children is now the root. Doesn't matter much + which, so long as we preserve the properties of the tree. */ + if (left) + { + sp->root = left; + + /* If there was a right child as well, hang it off the + right-most leaf of the left child. */ + if (right) + { + while (left->right) + left = left->right; + left->right = right; + } + } + else + sp->root = right; + } +} + +/* Lookup KEY in SP, returning VALUE if present, and NULL + otherwise. */ + +splay_tree_node +splay_tree_lookup (splay_tree sp, splay_tree_key key) +{ + splay_tree_splay (sp, key); + + if (sp->root && (*sp->comp)(sp->root->key, key) == 0) + return sp->root; + else + return 0; +} + +/* Return the node in SP with the greatest key. */ + +splay_tree_node +splay_tree_max (splay_tree sp) +{ + splay_tree_node n = sp->root; + + if (!n) + return NULL; + + while (n->right) + n = n->right; + + return n; +} + +/* Return the node in SP with the smallest key. */ + +splay_tree_node +splay_tree_min (splay_tree sp) +{ + splay_tree_node n = sp->root; + + if (!n) + return NULL; + + while (n->left) + n = n->left; + + return n; +} + +/* Return the immediate predecessor KEY, or NULL if there is no + predecessor. KEY need not be present in the tree. */ + +splay_tree_node +splay_tree_predecessor (splay_tree sp, splay_tree_key key) +{ + int comparison; + splay_tree_node node; + + /* If the tree is empty, there is certainly no predecessor. */ + if (!sp->root) + return NULL; + + /* Splay the tree around KEY. That will leave either the KEY + itself, its predecessor, or its successor at the root. */ + splay_tree_splay (sp, key); + comparison = (*sp->comp)(sp->root->key, key); + + /* If the predecessor is at the root, just return it. */ + if (comparison < 0) + return sp->root; + + /* Otherwise, find the rightmost element of the left subtree. */ + node = sp->root->left; + if (node) + while (node->right) + node = node->right; + + return node; +} + +/* Return the immediate successor KEY, or NULL if there is no + successor. KEY need not be present in the tree. */ + +splay_tree_node +splay_tree_successor (splay_tree sp, splay_tree_key key) +{ + int comparison; + splay_tree_node node; + + /* If the tree is empty, there is certainly no successor. */ + if (!sp->root) + return NULL; + + /* Splay the tree around KEY. That will leave either the KEY + itself, its predecessor, or its successor at the root. */ + splay_tree_splay (sp, key); + comparison = (*sp->comp)(sp->root->key, key); + + /* If the successor is at the root, just return it. */ + if (comparison > 0) + return sp->root; + + /* Otherwise, find the leftmost element of the right subtree. */ + node = sp->root->right; + if (node) + while (node->left) + node = node->left; + + return node; +} + +/* Call FN, passing it the DATA, for every node in SP, following an + in-order traversal. If FN every returns a non-zero value, the + iteration ceases immediately, and the value is returned. + Otherwise, this function returns 0. */ + +int +splay_tree_foreach (splay_tree sp, splay_tree_foreach_fn fn, void *data) +{ + return splay_tree_foreach_helper (sp->root, fn, data); +} + +/* Splay-tree comparison function, treating the keys as ints. */ + +int +splay_tree_compare_ints (splay_tree_key k1, splay_tree_key k2) +{ + if ((int) k1 < (int) k2) + return -1; + else if ((int) k1 > (int) k2) + return 1; + else + return 0; +} + +/* Splay-tree comparison function, treating the keys as pointers. */ + +int +splay_tree_compare_pointers (splay_tree_key k1, splay_tree_key k2) +{ + if ((char*) k1 < (char*) k2) + return -1; + else if ((char*) k1 > (char*) k2) + return 1; + else + return 0; +} -- cgit v1.2.3