Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(2)

Unified Diff: tools/relocation_packer/src/leb128.cc

Issue 404553003: Create builds configured for ARM and AARCH64. (Closed) Base URL: https://chromium.googlesource.com/chromium/src.git@master
Patch Set: Purge unused includes. Created 6 years, 5 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
Index: tools/relocation_packer/src/leb128.cc
diff --git a/tools/relocation_packer/src/leb128.cc b/tools/relocation_packer/src/leb128.cc
index a322fb1c28b3c5902000366568f244a5487404dc..b48739c324d1683c7d047bc79dd26d51387c9205 100644
--- a/tools/relocation_packer/src/leb128.cc
+++ b/tools/relocation_packer/src/leb128.cc
@@ -2,13 +2,13 @@
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
-// TODO(simonb): Extend for 64-bit target libraries.
-
#include "leb128.h"
#include <stdint.h>
#include <vector>
+#include "elf_traits.h"
+
namespace relocation_packer {
// Empty constructor and destructor to silence chromium-style.
@@ -18,16 +18,16 @@ Leb128Encoder::~Leb128Encoder() { }
// Add a single value to the encoding. Values are encoded with variable
// length. The least significant 7 bits of each byte hold 7 bits of data,
// and the most significant bit is set on each byte except the last.
-void Leb128Encoder::Enqueue(uint32_t value) {
- while (value > 127) {
- encoding_.push_back((1 << 7) | (value & 127));
+void Leb128Encoder::Enqueue(ELF::Xword value) {
+ do {
+ const uint8_t byte = value & 127;
value >>= 7;
- }
- encoding_.push_back(value);
+ encoding_.push_back((value ? 128 : 0) | byte);
+ } while (value);
}
// Add a vector of values to the encoding.
-void Leb128Encoder::EnqueueAll(const std::vector<uint32_t>& values) {
+void Leb128Encoder::EnqueueAll(const std::vector<ELF::Xword>& values) {
for (size_t i = 0; i < values.size(); ++i)
Enqueue(values[i]);
}
@@ -44,23 +44,24 @@ Leb128Decoder::~Leb128Decoder() { }
// Decode and retrieve a single value from the encoding. Read forwards until
// a byte without its most significant bit is found, then read the 7 bit
// fields of the bytes spanned to re-form the value.
-uint32_t Leb128Decoder::Dequeue() {
- size_t extent = cursor_;
- while (encoding_[extent] >> 7)
- extent++;
+ELF::Xword Leb128Decoder::Dequeue() {
+ ELF::Xword value = 0;
+
+ size_t shift = 0;
+ uint8_t byte;
- uint32_t value = 0;
- for (size_t i = extent; i > cursor_; --i) {
- value = (value << 7) | (encoding_[i] & 127);
- }
- value = (value << 7) | (encoding_[cursor_] & 127);
+ // Loop until we reach a byte with its high order bit clear.
+ do {
+ byte = encoding_[cursor_++];
+ value |= static_cast<ELF::Xword>(byte & 127) << shift;
+ shift += 7;
+ } while (byte & 128);
- cursor_ = extent + 1;
return value;
}
// Decode and retrieve all remaining values from the encoding.
-void Leb128Decoder::DequeueAll(std::vector<uint32_t>* values) {
+void Leb128Decoder::DequeueAll(std::vector<ELF::Xword>* values) {
while (cursor_ < encoding_.size())
values->push_back(Dequeue());
}

Powered by Google App Engine
This is Rietveld 408576698