Merge V8 5.3.332.45. DO NOT MERGE
Test: Manual
FPIIM-449
Change-Id: Id3254828b068abdea3cb10442e0172a8c9a98e03
(cherry picked from commit 13e2dadd00298019ed862f2b2fc5068bba730bcf)
diff --git a/src/eh-frame.cc b/src/eh-frame.cc
new file mode 100644
index 0000000..af85e0b
--- /dev/null
+++ b/src/eh-frame.cc
@@ -0,0 +1,96 @@
+// 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.
+
+#include "src/eh-frame.h"
+#include "src/objects-inl.h"
+#include "src/objects.h"
+
+namespace v8 {
+namespace internal {
+
+static const int DW_EH_PE_pcrel = 0x10;
+static const int DW_EH_PE_datarel = 0x30;
+static const int DW_EH_PE_udata4 = 0x03;
+static const int DW_EH_PE_sdata4 = 0x0b;
+
+const int EhFrameHdr::kCIESize = 0;
+
+static const int kVersionSize = 1;
+static const int kEncodingSpecifiersSize = 3;
+
+//
+// In order to calculate offsets in the .eh_frame_hdr, we must know the layout
+// of the DSO generated by perf inject, which is assumed to be the following:
+//
+// | ... | |
+// +---------------+ <-- (F) --- | Larger offsets in file
+// | | ^ |
+// | Instructions | | .text v
+// | | v
+// +---------------+ <-- (E) ---
+// |///////////////|
+// |////Padding////|
+// |///////////////|
+// +---------------+ <-- (D) ---
+// | | ^
+// | CIE | |
+// | | |
+// +---------------+ <-- (C) | .eh_frame
+// | | |
+// | FDE | |
+// | | v
+// +---------------+ <-- (B) ---
+// | version | ^
+// +---------------+ |
+// | encoding | |
+// | specifiers | |
+// +---------------+ <---(A) | .eh_frame_hdr
+// | offset to | |
+// | .eh_frame | |
+// +---------------+ |
+// | ... | ...
+//
+// (F) is aligned at a 16-byte boundary.
+// (D) is aligned at a 8-byte boundary.
+// (B) is aligned at a 4-byte boundary.
+// (E), (C) and (A) have no alignment requirements.
+//
+// The distance between (A) and (B) is 4 bytes.
+//
+// The size of the .eh_frame is required to be a multiple of the pointer size,
+// which means that (B) will be naturally aligned to a 4-byte boundary on all
+// the architectures we support.
+//
+// Because (E) has no alignment requirements, there is padding between (E) and
+// (D). (F) is aligned at a 16-byte boundary, thus to a 8-byte one as well.
+//
+EhFrameHdr::EhFrameHdr(Code* code) {
+ int code_size = code->is_crankshafted() ? code->safepoint_table_offset()
+ : code->instruction_size();
+ version_ = 1;
+ eh_frame_ptr_encoding_ = DW_EH_PE_sdata4 | DW_EH_PE_pcrel;
+ lut_size_encoding_ = DW_EH_PE_udata4;
+ lut_entries_encoding_ = DW_EH_PE_sdata4 | DW_EH_PE_datarel;
+
+ // .eh_frame pointer and LUT
+ if (code->has_unwinding_info()) {
+ DCHECK_GE(code->unwinding_info_size(), EhFrameHdr::kRecordSize);
+ int eh_frame_size = code->unwinding_info_size() - EhFrameHdr::kRecordSize;
+
+ offset_to_eh_frame_ =
+ -(eh_frame_size + kVersionSize + kEncodingSpecifiersSize); // A -> D
+ lut_entries_number_ = 1;
+ offset_to_procedure_ = -(RoundUp(code_size, 8) + eh_frame_size); // B -> F
+ offset_to_fde_ = -(eh_frame_size - kCIESize); // B -> C
+ } else {
+ // Create a dummy table
+ offset_to_eh_frame_ = 0;
+ lut_entries_number_ = 0;
+ offset_to_procedure_ = 0;
+ offset_to_fde_ = 0;
+ }
+}
+
+} // namespace internal
+} // namespace v8