v8/test/cctest/test-reloc-info.cc
ssanfilippo 7d073b03c7 This commit is the first step towards emitting unwinding information in
the .eh_frame format as part of the jitdump generated when
FLAG_perf_prof is enabled. The final goal is allowing precise unwinding
of callchains that include JITted code when profiling V8 using perf.

Unwinding information is stored in the body of code objects after the
code itself, prefixed with its length and aligned to a 8-byte boundary.
A boolean flag in the header signals its presence, resulting in zero
memory overhead when the generation of unwinding info is disabled or
no such information was attached to the code object.

A new jitdump record type (with id 4) is introduced for specifying
optional unwinding information for code load records. The EhFrameHdr
struct is also introduced, together with a constructor to initialise it
from the associated code object.

At this stage no unwinding information is written to the jitdump, but
the infrastructure for doing so is ready in place.

BUG=v8:4899
LOG=N

Review-Url: https://codereview.chromium.org/1993653003
Cr-Commit-Position: refs/heads/master@{#37296}
2016-06-27 15:10:41 +00:00

128 lines
4.8 KiB
C++

// Copyright 2011 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "src/assembler.h"
#include "src/macro-assembler.h"
#include "test/cctest/cctest.h"
namespace v8 {
namespace internal {
static void WriteRinfo(RelocInfoWriter* writer,
byte* pc, RelocInfo::Mode mode, intptr_t data) {
RelocInfo rinfo(CcTest::i_isolate(), pc, mode, data, NULL);
writer->Write(&rinfo);
}
// Tests that writing both types of positions and then reading either
// or both works as expected.
TEST(Positions) {
CcTest::InitializeVM();
const int code_size = 10 * KB;
int relocation_info_size = 10 * KB;
const int buffer_size = code_size + relocation_info_size;
v8::base::SmartArrayPointer<byte> buffer(new byte[buffer_size]);
byte* pc = buffer.get();
byte* buffer_end = buffer.get() + buffer_size;
RelocInfoWriter writer(buffer_end, pc);
byte* relocation_info_end = buffer_end - relocation_info_size;
for (int i = 0, pos = 0; i < 100; i++, pc += i, pos += i) {
RelocInfo::Mode mode = (i % 2 == 0) ?
RelocInfo::STATEMENT_POSITION : RelocInfo::POSITION;
if (mode == RelocInfo::STATEMENT_POSITION) {
printf("TEST WRITING STATEMENT %p %d\n", static_cast<void*>(pc), pos);
} else {
printf("TEST WRITING POSITION %p %d\n", static_cast<void*>(pc), pos);
}
WriteRinfo(&writer, pc, mode, pos);
CHECK(writer.pos() - RelocInfoWriter::kMaxSize >= relocation_info_end);
}
writer.Finish();
relocation_info_size = static_cast<int>(buffer_end - writer.pos());
MacroAssembler assm(CcTest::i_isolate(), nullptr, 0, CodeObjectRequired::kNo);
CodeDesc desc = {
buffer.get(), buffer_size, code_size, relocation_info_size, 0,
nullptr, 0, &assm};
// Read only (non-statement) positions.
{
RelocIterator it(desc, RelocInfo::ModeMask(RelocInfo::POSITION));
pc = buffer.get();
for (int i = 0, pos = 0; i < 100; i++, pc += i, pos += i) {
printf("TESTING 1: %d\n", i);
RelocInfo::Mode mode = (i % 2 == 0) ?
RelocInfo::STATEMENT_POSITION : RelocInfo::POSITION;
if (mode == RelocInfo::POSITION) {
CHECK_EQ(pc, it.rinfo()->pc());
CHECK_EQ(mode, it.rinfo()->rmode());
CHECK_EQ(pos, static_cast<int>(it.rinfo()->data()));
it.next();
}
}
CHECK(it.done());
}
// Read only statement positions.
{
RelocIterator it(desc, RelocInfo::ModeMask(RelocInfo::STATEMENT_POSITION));
pc = buffer.get();
for (int i = 0, pos = 0; i < 100; i++, pc += i, pos += i) {
RelocInfo::Mode mode = (i % 2 == 0) ?
RelocInfo::STATEMENT_POSITION : RelocInfo::POSITION;
if (mode == RelocInfo::STATEMENT_POSITION) {
CHECK_EQ(pc, it.rinfo()->pc());
CHECK_EQ(mode, it.rinfo()->rmode());
CHECK_EQ(pos, static_cast<int>(it.rinfo()->data()));
it.next();
}
}
CHECK(it.done());
}
// Read both types of positions.
{
RelocIterator it(desc, RelocInfo::kPositionMask);
pc = buffer.get();
for (int i = 0, pos = 0; i < 100; i++, pc += i, pos += i) {
RelocInfo::Mode mode = (i % 2 == 0) ?
RelocInfo::STATEMENT_POSITION : RelocInfo::POSITION;
CHECK_EQ(pc, it.rinfo()->pc());
CHECK_EQ(mode, it.rinfo()->rmode());
CHECK_EQ(pos, static_cast<int>(it.rinfo()->data()));
it.next();
}
CHECK(it.done());
}
}
} // namespace internal
} // namespace v8