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// 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 "test/unittests/test-utils.h"
namespace v8 {
namespace internal {
// Test enabled only on supported architectures.
#if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_ARM) || \
defined(V8_TARGET_ARCH_ARM64)
namespace {
class EhFrameWriterTest : public TestWithZone {
protected:
// Being a 7bit positive integer, this also serves as its ULEB128 encoding.
static const int kTestRegisterCode = 0;
static EhFrameIterator MakeIterator(EhFrameWriter* writer) {
CodeDesc desc;
writer->GetEhFrame(&desc);
DCHECK_GT(desc.unwinding_info_size, 0);
return EhFrameIterator(desc.unwinding_info,
desc.unwinding_info + desc.unwinding_info_size);
}
};
const int EhFrameWriterTest::kTestRegisterCode;
} // namespace
TEST_F(EhFrameWriterTest, Alignment) {
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(42 * EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
ASSERT_EQ(0, EhFrameConstants::kEhFrameHdrSize % 4);
ASSERT_EQ(0, EhFrameConstants::kEhFrameTerminatorSize % 4);
EXPECT_EQ(0, (iterator.GetBufferSize() - EhFrameConstants::kEhFrameHdrSize -
EhFrameConstants::kEhFrameTerminatorSize) %
kPointerSize);
}
TEST_F(EhFrameWriterTest, FDEHeader) {
static const int kProcedureSize = 0x5678ABCD;
EhFrameWriter writer(zone());
writer.Initialize();
writer.Finish(kProcedureSize);
EhFrameIterator iterator = MakeIterator(&writer);
int cie_size = iterator.GetNextUInt32();
iterator.Skip(cie_size);
int fde_size = iterator.GetNextUInt32();
EXPECT_EQ(iterator.GetBufferSize(),
fde_size + cie_size + EhFrameConstants::kEhFrameTerminatorSize +
EhFrameConstants::kEhFrameHdrSize + 2 * kInt32Size);
int backwards_offset_to_cie_offset = iterator.GetCurrentOffset();
int backwards_offset_to_cie = iterator.GetNextUInt32();
EXPECT_EQ(backwards_offset_to_cie_offset, backwards_offset_to_cie);
int procedure_address_offset = iterator.GetCurrentOffset();
int procedure_address = iterator.GetNextUInt32();
EXPECT_EQ(-(procedure_address_offset + RoundUp(kProcedureSize, 8)),
procedure_address);
int procedure_size = iterator.GetNextUInt32();
EXPECT_EQ(kProcedureSize, procedure_size);
}
TEST_F(EhFrameWriterTest, SetOffset) {
static const uint32_t kOffset = 0x0BADC0DE;
EhFrameWriter writer(zone());
writer.Initialize();
writer.SetBaseAddressOffset(kOffset);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kDefCfaOffset,
iterator.GetNextOpcode());
EXPECT_EQ(kOffset, iterator.GetNextULeb128());
}
TEST_F(EhFrameWriterTest, IncreaseOffset) {
static const uint32_t kFirstOffset = 121;
static const uint32_t kSecondOffset = 16;
EhFrameWriter writer(zone());
writer.Initialize();
writer.SetBaseAddressOffset(kFirstOffset);
writer.IncreaseBaseAddressOffset(kSecondOffset);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kDefCfaOffset,
iterator.GetNextOpcode());
EXPECT_EQ(kFirstOffset, iterator.GetNextULeb128());
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kDefCfaOffset,
iterator.GetNextOpcode());
EXPECT_EQ(kFirstOffset + kSecondOffset, iterator.GetNextULeb128());
}
TEST_F(EhFrameWriterTest, SetRegister) {
Register test_register = Register::from_code(kTestRegisterCode);
EhFrameWriter writer(zone());
writer.Initialize();
writer.SetBaseAddressRegister(test_register);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kDefCfaRegister,
iterator.GetNextOpcode());
EXPECT_EQ(static_cast<uint32_t>(kTestRegisterCode),
iterator.GetNextULeb128());
}
TEST_F(EhFrameWriterTest, SetRegisterAndOffset) {
Register test_register = Register::from_code(kTestRegisterCode);
static const uint32_t kOffset = 0x0BADC0DE;
EhFrameWriter writer(zone());
writer.Initialize();
writer.SetBaseAddressRegisterAndOffset(test_register, kOffset);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kDefCfa, iterator.GetNextOpcode());
EXPECT_EQ(static_cast<uint32_t>(kTestRegisterCode),
iterator.GetNextULeb128());
EXPECT_EQ(kOffset, iterator.GetNextULeb128());
}
TEST_F(EhFrameWriterTest, PcOffsetEncoding6bit) {
static const int kOffset = 42;
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(kOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ((1 << 6) | kOffset, iterator.GetNextByte());
}
TEST_F(EhFrameWriterTest, PcOffsetEncoding6bitDelta) {
static const int kFirstOffset = 42;
static const int kSecondOffset = 62;
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(kFirstOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.AdvanceLocation(kSecondOffset *
EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ((1 << 6) | kFirstOffset, iterator.GetNextByte());
EXPECT_EQ((1 << 6) | (kSecondOffset - kFirstOffset), iterator.GetNextByte());
}
TEST_F(EhFrameWriterTest, PcOffsetEncoding8bit) {
static const int kOffset = 0x42;
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(kOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kAdvanceLoc1,
iterator.GetNextOpcode());
EXPECT_EQ(kOffset, iterator.GetNextByte());
}
TEST_F(EhFrameWriterTest, PcOffsetEncoding8bitDelta) {
static const int kFirstOffset = 0x10;
static const int kSecondOffset = 0x70;
static const int kThirdOffset = 0xB5;
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(kFirstOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.AdvanceLocation(kSecondOffset *
EhFrameConstants::kCodeAlignmentFactor);
writer.AdvanceLocation(kThirdOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ((1 << 6) | kFirstOffset, iterator.GetNextByte());
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kAdvanceLoc1,
iterator.GetNextOpcode());
EXPECT_EQ(kSecondOffset - kFirstOffset, iterator.GetNextByte());
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kAdvanceLoc1,
iterator.GetNextOpcode());
EXPECT_EQ(kThirdOffset - kSecondOffset, iterator.GetNextByte());
}
TEST_F(EhFrameWriterTest, PcOffsetEncoding16bit) {
static const int kOffset = kMaxUInt8 + 42;
ASSERT_LT(kOffset, kMaxUInt16);
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(kOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kAdvanceLoc2,
iterator.GetNextOpcode());
EXPECT_EQ(kOffset, iterator.GetNextUInt16());
}
TEST_F(EhFrameWriterTest, PcOffsetEncoding16bitDelta) {
static const int kFirstOffset = 0x41;
static const int kSecondOffset = kMaxUInt8 + 0x42;
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(kFirstOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.AdvanceLocation(kSecondOffset *
EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kAdvanceLoc1,
iterator.GetNextOpcode());
EXPECT_EQ(kFirstOffset, iterator.GetNextByte());
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kAdvanceLoc2,
iterator.GetNextOpcode());
EXPECT_EQ(kSecondOffset - kFirstOffset, iterator.GetNextUInt16());
}
TEST_F(EhFrameWriterTest, PcOffsetEncoding32bit) {
static const uint32_t kOffset = kMaxUInt16 + 42;
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(kOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kAdvanceLoc4,
iterator.GetNextOpcode());
EXPECT_EQ(kOffset, iterator.GetNextUInt32());
}
TEST_F(EhFrameWriterTest, PcOffsetEncoding32bitDelta) {
static const uint32_t kFirstOffset = kMaxUInt16 + 0x42;
static const uint32_t kSecondOffset = kMaxUInt16 + 0x67;
EhFrameWriter writer(zone());
writer.Initialize();
writer.AdvanceLocation(kFirstOffset * EhFrameConstants::kCodeAlignmentFactor);
writer.AdvanceLocation(kSecondOffset *
EhFrameConstants::kCodeAlignmentFactor);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kAdvanceLoc4,
iterator.GetNextOpcode());
EXPECT_EQ(kFirstOffset, iterator.GetNextUInt32());
EXPECT_EQ((1 << 6) | (kSecondOffset - kFirstOffset), iterator.GetNextByte());
}
TEST_F(EhFrameWriterTest, SaveRegisterUnsignedOffset) {
Register test_register = Register::from_code(kTestRegisterCode);
static const int kOffset =
EhFrameConstants::kDataAlignmentFactor > 0 ? 12344 : -12344;
EhFrameWriter writer(zone());
writer.Initialize();
writer.RecordRegisterSavedToStack(test_register, kOffset);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ((2 << 6) | kTestRegisterCode, iterator.GetNextByte());
EXPECT_EQ(
static_cast<uint32_t>(kOffset / EhFrameConstants::kDataAlignmentFactor),
iterator.GetNextULeb128());
}
TEST_F(EhFrameWriterTest, SaveRegisterSignedOffset) {
Register test_register = Register::from_code(kTestRegisterCode);
static const int kOffset =
EhFrameConstants::kDataAlignmentFactor < 0 ? 12344 : -12344;
ASSERT_EQ(kOffset % EhFrameConstants::kDataAlignmentFactor, 0);
EhFrameWriter writer(zone());
writer.Initialize();
writer.RecordRegisterSavedToStack(test_register, kOffset);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kOffsetExtendedSf,
iterator.GetNextOpcode());
EXPECT_EQ(static_cast<uint32_t>(kTestRegisterCode),
iterator.GetNextULeb128());
EXPECT_EQ(kOffset / EhFrameConstants::kDataAlignmentFactor,
iterator.GetNextSLeb128());
}
TEST_F(EhFrameWriterTest, RegisterNotModified) {
Register test_register = Register::from_code(kTestRegisterCode);
EhFrameWriter writer(zone());
writer.Initialize();
writer.RecordRegisterNotModified(test_register);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ(EhFrameConstants::DwarfOpcodes::kSameValue,
iterator.GetNextOpcode());
EXPECT_EQ(static_cast<uint32_t>(kTestRegisterCode),
iterator.GetNextULeb128());
}
TEST_F(EhFrameWriterTest, RegisterFollowsInitialRule) {
Register test_register = Register::from_code(kTestRegisterCode);
EhFrameWriter writer(zone());
writer.Initialize();
writer.RecordRegisterFollowsInitialRule(test_register);
writer.Finish(100);
EhFrameIterator iterator = MakeIterator(&writer);
iterator.SkipToFdeDirectives();
EXPECT_EQ((3 << 6) | kTestRegisterCode, iterator.GetNextByte());
}
TEST_F(EhFrameWriterTest, EhFrameHdrLayout) {
static const int kCodeSize = 10;
static const int kPaddingSize = 6;
EhFrameWriter writer(zone());
writer.Initialize();
writer.Finish(kCodeSize);
EhFrameIterator iterator = MakeIterator(&writer);
// Skip the .eh_frame.
int encoded_cie_size = iterator.GetNextUInt32();
iterator.Skip(encoded_cie_size);
int cie_size = encoded_cie_size + kInt32Size;
int encoded_fde_size = iterator.GetNextUInt32();
iterator.Skip(encoded_fde_size);
int fde_size = encoded_fde_size + kInt32Size;
iterator.Skip(EhFrameConstants::kEhFrameTerminatorSize);
int eh_frame_size =
cie_size + fde_size + EhFrameConstants::kEhFrameTerminatorSize;
//
// Plugging some numbers in the DSO layout shown in eh-frame.cc:
//
// | ... |
// +---------------+ <-- (E) ---------
// | | ^
// | Instructions | 10 bytes | .text
// | | v
// +---------------+ <----------------
// |///////////////|
// |////Padding////| 6 bytes
// |///////////////|
// +---------------+ <---(D)----------
// | | ^
// | CIE | cie_size bytes* |
// | | |
// +---------------+ <-- (C) |
// | | | .eh_frame
// | FDE | fde_size bytes |
// | | |
// +---------------+ |
// | terminator | 4 bytes v
// +---------------+ <-- (B) ---------
// | version | ^
// +---------------+ 4 bytes |
// | encoding | |
// | specifiers | |
// +---------------+ <---(A) | .eh_frame_hdr
// | offset to | |
// | .eh_frame | |
// +---------------+ |
// | ... | ...
//
// (*) the size of the CIE is platform dependent.
//
int eh_frame_hdr_version = iterator.GetNextByte();
EXPECT_EQ(EhFrameConstants::kEhFrameHdrVersion, eh_frame_hdr_version);
// .eh_frame pointer encoding specifier.
EXPECT_EQ(EhFrameConstants::kSData4 | EhFrameConstants::kPcRel,
iterator.GetNextByte());
// Lookup table size encoding specifier.
EXPECT_EQ(EhFrameConstants::kUData4, iterator.GetNextByte());
// Lookup table pointers encoding specifier.
EXPECT_EQ(EhFrameConstants::kSData4 | EhFrameConstants::kDataRel,
iterator.GetNextByte());
// A -> D
int offset_to_eh_frame = iterator.GetNextUInt32();
EXPECT_EQ(-(EhFrameConstants::kFdeVersionSize +
EhFrameConstants::kFdeEncodingSpecifiersSize + eh_frame_size),
offset_to_eh_frame);
int lut_entries = iterator.GetNextUInt32();
EXPECT_EQ(1, lut_entries);
// B -> E
int offset_to_procedure = iterator.GetNextUInt32();
EXPECT_EQ(-(eh_frame_size + kPaddingSize + kCodeSize), offset_to_procedure);
// B -> C
int offset_to_fde = iterator.GetNextUInt32();
EXPECT_EQ(-(fde_size + EhFrameConstants::kEhFrameTerminatorSize),
offset_to_fde);
}
#endif
} // namespace internal
} // namespace v8
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