Merge V8 5.2.361.47 DO NOT MERGE
https://chromium.googlesource.com/v8/v8/+/5.2.361.47
FPIIM-449
Change-Id: Ibec421b85a9b88cb3a432ada642e469fe7e78346
(cherry picked from commit bcf72ee8e3b26f1d0726869c7ddb3921c68b09a8)
diff --git a/src/wasm/leb-helper.h b/src/wasm/leb-helper.h
new file mode 100644
index 0000000..7ba244d
--- /dev/null
+++ b/src/wasm/leb-helper.h
@@ -0,0 +1,131 @@
+// Copyright 2016 the V8 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.
+
+#ifndef V8_WASM_LEB_HELPER_H_
+#define V8_WASM_LEB_HELPER_H_
+
+namespace v8 {
+namespace internal {
+namespace wasm {
+
+class LEBHelper {
+ public:
+ // Write a 32-bit unsigned LEB to {dest}, updating {dest} to point after
+ // the last uint8_t written. No safety checks.
+ static void write_u32v(uint8_t** dest, uint32_t val) {
+ while (val >= 0x80) {
+ *((*dest)++) = static_cast<uint8_t>(0x80 | (val & 0x7F));
+ val >>= 7;
+ }
+ *((*dest)++) = static_cast<uint8_t>(val & 0x7F);
+ }
+
+ // Write a 32-bit signed LEB to {dest}, updating {dest} to point after
+ // the last uint8_t written. No safety checks.
+ static void write_i32v(uint8_t** dest, int32_t val) {
+ if (val >= 0) {
+ while (val >= 0x40) { // prevent sign extension.
+ *((*dest)++) = static_cast<uint8_t>(0x80 | (val & 0x7F));
+ val >>= 7;
+ }
+ *((*dest)++) = static_cast<uint8_t>(val & 0xFF);
+ } else {
+ while ((val >> 6) != -1) {
+ *((*dest)++) = static_cast<uint8_t>(0x80 | (val & 0x7F));
+ val >>= 7;
+ }
+ *((*dest)++) = static_cast<uint8_t>(val & 0x7F);
+ }
+ }
+
+ // Write a 64-bit unsigned LEB to {dest}, updating {dest} to point after
+ // the last uint8_t written. No safety checks.
+ static void write_u64v(uint8_t** dest, uint64_t val) {
+ while (val >= 0x80) {
+ *((*dest)++) = static_cast<uint8_t>(0x80 | (val & 0x7F));
+ val >>= 7;
+ }
+ *((*dest)++) = static_cast<uint8_t>(val & 0x7F);
+ }
+
+ // Write a 64-bit signed LEB to {dest}, updating {dest} to point after
+ // the last uint8_t written. No safety checks.
+ static void write_i64v(uint8_t** dest, int64_t val) {
+ if (val >= 0) {
+ while (val >= 0x40) { // prevent sign extension.
+ *((*dest)++) = static_cast<uint8_t>(0x80 | (val & 0x7F));
+ val >>= 7;
+ }
+ *((*dest)++) = static_cast<uint8_t>(val & 0xFF);
+ } else {
+ while ((val >> 6) != -1) {
+ *((*dest)++) = static_cast<uint8_t>(0x80 | (val & 0x7F));
+ val >>= 7;
+ }
+ *((*dest)++) = static_cast<uint8_t>(val & 0x7F);
+ }
+ }
+
+ // TODO(titzer): move core logic for decoding LEBs from decoder.h to here.
+
+ // Compute the size of {val} if emitted as an LEB32.
+ static inline size_t sizeof_u32v(size_t val) {
+ size_t size = 0;
+ do {
+ size++;
+ val = val >> 7;
+ } while (val > 0);
+ return size;
+ }
+
+ // Compute the size of {val} if emitted as an LEB32.
+ static inline size_t sizeof_i32v(int32_t val) {
+ size_t size = 1;
+ if (val >= 0) {
+ while (val >= 0x40) { // prevent sign extension.
+ size++;
+ val >>= 7;
+ }
+ } else {
+ while ((val >> 6) != -1) {
+ size++;
+ val >>= 7;
+ }
+ }
+ return size;
+ }
+
+ // Compute the size of {val} if emitted as an unsigned LEB64.
+ static inline size_t sizeof_u64v(uint64_t val) {
+ size_t size = 0;
+ do {
+ size++;
+ val = val >> 7;
+ } while (val > 0);
+ return size;
+ }
+
+ // Compute the size of {val} if emitted as a signed LEB64.
+ static inline size_t sizeof_i64v(int64_t val) {
+ size_t size = 1;
+ if (val >= 0) {
+ while (val >= 0x40) { // prevent sign extension.
+ size++;
+ val >>= 7;
+ }
+ } else {
+ while ((val >> 6) != -1) {
+ size++;
+ val >>= 7;
+ }
+ }
+ return size;
+ }
+};
+
+} // namespace wasm
+} // namespace internal
+} // namespace v8
+
+#endif // V8_WASM_LEB_HELPER_H_