+/*********************************************************************
+ *
+ * Copyright 2006 Keith Packard and Carl Worth
+ * Copyright 2012 Intel Corporation
+ * Copyright 2012 VMware, Inc.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ *********************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits>
+
+#include "trace_fast_callset.hpp"
+
+using namespace trace;
+
+#define MAX_LEVEL 16
+
+FastCallRange::FastCallRange(CallNo first, CallNo last, int level)
+{
+ this->first = first;
+ this->last = last;
+ this->level = level;
+
+ next = new FastCallRange*[level];
+}
+
+bool
+FastCallRange::contains(CallNo call_no)
+{
+ return (first <= call_no && last >= call_no);
+}
+
+FastCallSet::FastCallSet(): head(0, 0, MAX_LEVEL)
+{
+ head.first = std::numeric_limits<CallNo>::max();
+ head.last = std::numeric_limits<CallNo>::min();
+
+ for (int i = 0; i < MAX_LEVEL; i++)
+ head.next[i] = NULL;
+
+ max_level = 0;
+}
+
+/*
+ * Generate a random level number, distributed
+ * so that each level is 1/4 as likely as the one before
+ *
+ * Note that level numbers run 1 <= level < MAX_LEVEL
+ */
+static int
+random_level (void)
+{
+ /* tricky bit -- each bit is '1' 75% of the time */
+ long int bits = random() | random();
+ int level = 1;
+
+ while (level < MAX_LEVEL)
+ {
+ if (bits & 1)
+ break;
+ level++;
+ bits >>= 1;
+ }
+
+ return level;
+}
+
+void
+FastCallSet::add(CallNo first, CallNo last)
+{
+ FastCallRange **update[MAX_LEVEL];
+ FastCallRange *node, *next;
+ int i, level;
+
+ /* Find node immediately before insertion point. */
+ node = &head;
+ for (i = max_level - 1; i >= 0; i--) {
+ while (node->next[i] && first > node->next[i]->last) {
+ node = node->next[i];
+ }
+ update[i] = &node->next[i];
+ }
+
+ /* Can we contain first by expanding tail of current range by 1? */
+ if (node != &head && node->last == first - 1) {
+
+ node->last = last;
+ goto MERGE_NODE_WITH_SUBSEQUENT_COVERED_NODES;
+
+ }
+
+ /* Current range could not contain first, look at next. */
+ node = node->next[0];
+
+ if (node) {
+ /* Do nothing if new range is already entirely contained. */
+ if (node->first <= first && node->last >= last) {
+ return;
+ }
+
+ /* If last is already included, we can simply expand
+ * node->first to fully include the range. */
+ if (node->first <= last && node->last >= last) {
+ node->first = first;
+ return;
+ }
+
+ /* This is our candidate node if first is contained */
+ if (node->first <= first && node->last >= first) {
+ node->last = last;
+ goto MERGE_NODE_WITH_SUBSEQUENT_COVERED_NODES;
+ }
+ }
+
+ /* Not possible to expand any existing node, so create a new one. */
+
+ level = random_level();
+
+ /* Handle first node of this level. */
+ if (level > max_level) {
+ level = max_level + 1;
+ update[max_level] = &head.next[max_level];
+ max_level = level;
+ }
+
+ node = new FastCallRange(first, last, level);
+
+ /* Perform insertion into all lists. */
+ for (i = 0; i < level; i++) {
+ node->next[i] = *update[i];
+ *update[i] = node;
+ }
+
+MERGE_NODE_WITH_SUBSEQUENT_COVERED_NODES:
+ next = node->next[0];
+ while (next && next->first <= node->last + 1) {
+ if (next->last > node->last)
+ node->last = next->last;
+
+ /* Delete node 'next' */
+ for (i = 0; i < node->level && i < next->level; i++) {
+ node->next[i] = next->next[i];
+ }
+
+ for (; i < next->level; i++) {
+ *update[i] = next->next[i];
+ }
+
+ delete next;
+
+ next = node->next[0];
+ }
+}
+
+void
+FastCallSet::add(CallNo call_no)
+{
+ this->add(call_no, call_no);
+}
+
+bool
+FastCallSet::contains(CallNo call_no)
+{
+ FastCallRange *node;
+ int i;
+
+ node = &head;
+ for (i = max_level - 1; i >= 0; i--) {
+ while (node->next[i] && call_no > node->next[i]->last) {
+ node = node->next[i];
+ }
+ }
+
+ node = node->next[0];
+
+ if (node == NULL)
+ return false;
+
+ return node->contains(call_no);
+}
projects / apitrace / commitdiff