summaryrefslogtreecommitdiffstats
path: root/gfx/angle/src/libANGLE/HandleRangeAllocator.cpp
diff options
context:
space:
mode:
authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /gfx/angle/src/libANGLE/HandleRangeAllocator.cpp
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
downloadUXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar
UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.gz
UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.lz
UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.xz
UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.zip
Add m-esr52 at 52.6.0
Diffstat (limited to 'gfx/angle/src/libANGLE/HandleRangeAllocator.cpp')
-rwxr-xr-xgfx/angle/src/libANGLE/HandleRangeAllocator.cpp225
1 files changed, 225 insertions, 0 deletions
diff --git a/gfx/angle/src/libANGLE/HandleRangeAllocator.cpp b/gfx/angle/src/libANGLE/HandleRangeAllocator.cpp
new file mode 100755
index 000000000..500a79629
--- /dev/null
+++ b/gfx/angle/src/libANGLE/HandleRangeAllocator.cpp
@@ -0,0 +1,225 @@
+//
+// Copyright (c) 2016 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+// HandleRangeAllocator.cpp : Implementation for HandleRangeAllocator.h
+
+#include "libANGLE/HandleRangeAllocator.h"
+
+#include <algorithm>
+#include <limits>
+#include <utility>
+
+#include "common/angleutils.h"
+#include "common/debug.h"
+
+namespace gl
+{
+
+const GLuint HandleRangeAllocator::kInvalidHandle = 0;
+
+HandleRangeAllocator::HandleRangeAllocator()
+{
+ // Simplify the code by making sure that lower_bound(id) never
+ // returns the beginning of the map, if id is valid (eg != kInvalidHandle).
+ mUsed.insert(std::make_pair(0u, 0u));
+}
+
+GLuint HandleRangeAllocator::allocate()
+{
+ return allocateRange(1u);
+}
+
+GLuint HandleRangeAllocator::allocateAtOrAbove(GLuint wanted)
+{
+ if (wanted == 0u || wanted == 1u)
+ return allocateRange(1u);
+
+ auto current = mUsed.lower_bound(wanted);
+ auto next = current;
+ if (current == mUsed.end() || current->first > wanted)
+ {
+ current--;
+ }
+ else
+ {
+ next++;
+ }
+
+ GLuint firstId = current->first;
+ GLuint lastId = current->second;
+ ASSERT(wanted >= firstId);
+
+ if (wanted - 1u <= lastId)
+ {
+ // Append to current range.
+ lastId++;
+ if (lastId == 0)
+ {
+ // The increment overflowed.
+ return allocateRange(1u);
+ }
+
+ current->second = lastId;
+
+ if (next != mUsed.end() && next->first - 1u == lastId)
+ {
+ // Merge with next range.
+ current->second = next->second;
+ mUsed.erase(next);
+ }
+ return lastId;
+ }
+ else if (next != mUsed.end() && next->first - 1u == wanted)
+ {
+ // Prepend to next range.
+ GLuint lastExisting = next->second;
+ mUsed.erase(next);
+ mUsed.insert(std::make_pair(wanted, lastExisting));
+ return wanted;
+ }
+ mUsed.insert(std::make_pair(wanted, wanted));
+ return wanted;
+}
+
+GLuint HandleRangeAllocator::allocateRange(GLuint range)
+{
+ ASSERT(range != 0);
+
+ auto current = mUsed.begin();
+ auto next = current;
+
+ while (++next != mUsed.end())
+ {
+ if (next->first - current->second > range)
+ break;
+ current = next;
+ }
+ const GLuint firstId = current->second + 1u;
+ const GLuint lastId = firstId + range - 1u;
+
+ // deal with wraparound
+ if (firstId == 0u || lastId < firstId)
+ return kInvalidHandle;
+
+ current->second = lastId;
+
+ if (next != mUsed.end() && next->first - 1u == lastId)
+ {
+ // merge with next range
+ current->second = next->second;
+ mUsed.erase(next);
+ }
+ return firstId;
+}
+
+bool HandleRangeAllocator::markAsUsed(GLuint handle)
+{
+ ASSERT(handle);
+ auto current = mUsed.lower_bound(handle);
+ if (current != mUsed.end() && current->first == handle)
+ return false;
+
+ auto next = current;
+ --current;
+
+ if (current->second >= handle)
+ return false;
+
+ ASSERT(current->first < handle && current->second < handle);
+
+ if (current->second + 1u == handle)
+ {
+ // Append to current range.
+ current->second = handle;
+ if (next != mUsed.end() && next->first - 1u == handle)
+ {
+ // Merge with next range.
+ current->second = next->second;
+ mUsed.erase(next);
+ }
+ return true;
+ }
+ else if (next != mUsed.end() && next->first - 1u == handle)
+ {
+ // Prepend to next range.
+ GLuint lastExisting = next->second;
+ mUsed.erase(next);
+ mUsed.insert(std::make_pair(handle, lastExisting));
+ return true;
+ }
+
+ mUsed.insert(std::make_pair(handle, handle));
+ return true;
+}
+
+void HandleRangeAllocator::release(GLuint handle)
+{
+ releaseRange(handle, 1u);
+}
+
+void HandleRangeAllocator::releaseRange(GLuint first, GLuint range)
+{
+ if (range == 0u || (first == 0u && range == 1u))
+ return;
+
+ if (first == 0u)
+ {
+ first++;
+ range--;
+ }
+
+ GLuint last = first + range - 1u;
+ if (last < first)
+ last = std::numeric_limits<GLuint>::max();
+
+ while (true)
+ {
+ auto current = mUsed.lower_bound(last);
+ if (current == mUsed.end() || current->first > last)
+ --current;
+
+ if (current->second < first)
+ return;
+
+ if (current->first >= first)
+ {
+ const GLuint lastExisting = current->second;
+ mUsed.erase(current);
+ if (last < lastExisting)
+ {
+ mUsed.insert(std::make_pair(last + 1u, lastExisting));
+ }
+ }
+ else if (current->second <= last)
+ {
+ current->second = first - 1u;
+ }
+ else
+ {
+ ASSERT(current->first < first && current->second > last);
+ const GLuint lastExisting = current->second;
+ current->second = first - 1u;
+ mUsed.insert(std::make_pair(last + 1u, lastExisting));
+ }
+ }
+}
+
+bool HandleRangeAllocator::isUsed(GLuint handle) const
+{
+ if (handle == kInvalidHandle)
+ return false;
+
+ auto current = mUsed.lower_bound(handle);
+ if (current != mUsed.end())
+ {
+ if (current->first == handle)
+ return true;
+ }
+ --current;
+ return current->second >= handle;
+}
+
+} // namespace gl \ No newline at end of file