blob: c452db3c87c23c3d5251b825528eba34ba85c256 [file] [log] [blame]
// Copyright 2018 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 "include/v8.h"
#include "src/api/api-inl.h"
#include "src/builtins/builtins.h"
#include "src/execution/isolate.h"
#include "src/heap/spaces.h"
#include "src/objects/code-inl.h"
#include "test/cctest/cctest.h"
namespace v8 {
namespace internal {
namespace test_unwinder {
static void* unlimited_stack_base = std::numeric_limits<void*>::max();
TEST(Unwind_BadState_Fail) {
UnwindState unwind_state; // Fields are intialized to nullptr.
RegisterState register_state;
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
unlimited_stack_base);
CHECK(!unwound);
// The register state should not change when unwinding fails.
CHECK_NULL(register_state.fp);
CHECK_NULL(register_state.sp);
CHECK_NULL(register_state.pc);
}
TEST(Unwind_BuiltinPCInMiddle_Success) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
uintptr_t stack[3];
void* stack_base = stack + arraysize(stack);
stack[0] = reinterpret_cast<uintptr_t>(stack + 2); // saved FP (rbp).
stack[1] = 202; // Return address into C++ code.
stack[2] = 303; // The SP points here in the caller's frame.
register_state.sp = stack;
register_state.fp = stack;
// Put the current PC inside of a valid builtin.
Code builtin = i_isolate->builtins()->builtin(Builtins::kStringEqual);
const uintptr_t offset = 40;
CHECK_LT(offset, builtin.InstructionSize());
register_state.pc =
reinterpret_cast<void*>(builtin.InstructionStart() + offset);
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
CHECK(unwound);
CHECK_EQ(reinterpret_cast<void*>(stack + 2), register_state.fp);
CHECK_EQ(reinterpret_cast<void*>(stack + 2), register_state.sp);
CHECK_EQ(reinterpret_cast<void*>(202), register_state.pc);
}
// The unwinder should be able to unwind even if we haven't properly set up the
// current frame, as long as there is another JS frame underneath us (i.e. as
// long as the PC isn't in JSEntry). This test puts the PC at the start
// of a JS builtin and creates a fake JSEntry frame before it on the stack. The
// unwinder should be able to unwind to the C++ frame before the JSEntry frame.
TEST(Unwind_BuiltinPCAtStart_Success) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
const size_t code_length = 40;
uintptr_t code[code_length] = {0};
unwind_state.code_range.start = code;
unwind_state.code_range.length_in_bytes = code_length * sizeof(uintptr_t);
uintptr_t stack[6];
void* stack_base = stack + arraysize(stack);
stack[0] = 101;
// Return address into JS code. It doesn't matter that this is not actually in
// JSEntry, because we only check that for the top frame.
stack[1] = reinterpret_cast<uintptr_t>(code + 10);
stack[2] = reinterpret_cast<uintptr_t>(stack + 5); // saved FP (rbp).
stack[3] = 303; // Return address into C++ code.
stack[4] = 404;
stack[5] = 505;
register_state.sp = stack;
register_state.fp = stack + 2; // FP to the JSEntry frame.
// Put the current PC at the start of a valid builtin, so that we are setting
// up the frame.
Code builtin = i_isolate->builtins()->builtin(Builtins::kStringEqual);
register_state.pc = reinterpret_cast<void*>(builtin.InstructionStart());
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
CHECK(unwound);
CHECK_EQ(reinterpret_cast<void*>(stack + 5), register_state.fp);
CHECK_EQ(reinterpret_cast<void*>(stack + 4), register_state.sp);
CHECK_EQ(reinterpret_cast<void*>(303), register_state.pc);
}
const char* foo_source = R"(
function foo(a, b) {
let x = a * b;
let y = x ^ b;
let z = y / a;
return x + y - z;
};
%PrepareFunctionForOptimization(foo);
foo(1, 2);
foo(1, 2);
%OptimizeFunctionOnNextCall(foo);
foo(1, 2);
)";
// Check that we can unwind when the pc is within an optimized code object on
// the V8 heap.
TEST(Unwind_CodeObjectPCInMiddle_Success) {
FLAG_allow_natives_syntax = true;
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
HandleScope scope(i_isolate);
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
uintptr_t stack[3];
void* stack_base = stack + arraysize(stack);
stack[0] = reinterpret_cast<uintptr_t>(stack + 2); // saved FP (rbp).
stack[1] = 202; // Return address into C++ code.
stack[2] = 303; // The SP points here in the caller's frame.
register_state.sp = stack;
register_state.fp = stack;
// Create an on-heap code object. Make sure we run the function so that it is
// compiled and not just marked for lazy compilation.
CompileRun(foo_source);
v8::Local<v8::Function> local_foo = v8::Local<v8::Function>::Cast(
env.local()->Global()->Get(env.local(), v8_str("foo")).ToLocalChecked());
Handle<JSFunction> foo =
Handle<JSFunction>::cast(v8::Utils::OpenHandle(*local_foo));
// Put the current PC inside of the created code object.
AbstractCode abstract_code = foo->abstract_code();
// We don't produce optimized code when run with --no-opt.
if (!abstract_code.IsCode() && FLAG_opt == false) return;
CHECK(abstract_code.IsCode());
Code code = abstract_code.GetCode();
// We don't want the offset too early or it could be the `push rbp`
// instruction (which is not at the start of generated code, because the lazy
// deopt check happens before frame setup).
const uintptr_t offset = code.InstructionSize() - 20;
CHECK_LT(offset, code.InstructionSize());
Address pc = code.InstructionStart() + offset;
register_state.pc = reinterpret_cast<void*>(pc);
// Check that the created code is within the code range that we get from the
// API.
Address start = reinterpret_cast<Address>(unwind_state.code_range.start);
CHECK(pc >= start && pc < start + unwind_state.code_range.length_in_bytes);
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
CHECK(unwound);
CHECK_EQ(reinterpret_cast<void*>(stack + 2), register_state.fp);
CHECK_EQ(reinterpret_cast<void*>(stack + 2), register_state.sp);
CHECK_EQ(reinterpret_cast<void*>(202), register_state.pc);
}
// If the PC is within JSEntry but we haven't set up the frame yet, then we
// cannot unwind.
TEST(Unwind_JSEntryBeforeFrame_Fail) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
const size_t code_length = 40;
uintptr_t code[code_length] = {0};
unwind_state.code_range.start = code;
unwind_state.code_range.length_in_bytes = code_length * sizeof(uintptr_t);
// Pretend that it takes 5 instructions to set up the frame in JSEntry.
unwind_state.js_entry_stub.code.start = code + 10;
unwind_state.js_entry_stub.code.length_in_bytes = 10 * sizeof(uintptr_t);
uintptr_t stack[10];
void* stack_base = stack + arraysize(stack);
stack[0] = 101;
stack[1] = 111;
stack[2] = 121;
stack[3] = 131;
stack[4] = 141;
stack[5] = 151;
stack[6] = 100; // Return address into C++ code.
stack[7] = 303; // The SP points here in the caller's frame.
stack[8] = 404;
stack[9] = 505;
register_state.sp = stack + 5;
register_state.fp = stack + 9;
// Put the current PC inside of JSEntry, before the frame is set up.
register_state.pc = code + 12;
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
CHECK(!unwound);
// The register state should not change when unwinding fails.
CHECK_EQ(reinterpret_cast<void*>(stack + 9), register_state.fp);
CHECK_EQ(reinterpret_cast<void*>(stack + 5), register_state.sp);
CHECK_EQ(code + 12, register_state.pc);
// Change the PC to a few instructions later, after the frame is set up.
register_state.pc = code + 16;
unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
// TODO(petermarshall): More precisely check position within JSEntry rather
// than just assuming the frame is unreadable.
CHECK(!unwound);
// The register state should not change when unwinding fails.
CHECK_EQ(reinterpret_cast<void*>(stack + 9), register_state.fp);
CHECK_EQ(reinterpret_cast<void*>(stack + 5), register_state.sp);
CHECK_EQ(code + 16, register_state.pc);
}
TEST(Unwind_OneJSFrame_Success) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
// Use a fake code range so that we can initialize it to 0s.
const size_t code_length = 40;
uintptr_t code[code_length] = {0};
unwind_state.code_range.start = code;
unwind_state.code_range.length_in_bytes = code_length * sizeof(uintptr_t);
// Our fake stack has two frames - one C++ frame and one JS frame (on top).
// The stack grows from high addresses to low addresses.
uintptr_t stack[10];
void* stack_base = stack + arraysize(stack);
stack[0] = 101;
stack[1] = 111;
stack[2] = 121;
stack[3] = 131;
stack[4] = 141;
stack[5] = reinterpret_cast<uintptr_t>(stack + 9); // saved FP (rbp).
stack[6] = 100; // Return address into C++ code.
stack[7] = 303; // The SP points here in the caller's frame.
stack[8] = 404;
stack[9] = 505;
register_state.sp = stack;
register_state.fp = stack + 5;
// Put the current PC inside of the code range so it looks valid.
register_state.pc = code + 30;
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
CHECK(unwound);
CHECK_EQ(reinterpret_cast<void*>(stack + 9), register_state.fp);
CHECK_EQ(reinterpret_cast<void*>(stack + 7), register_state.sp);
CHECK_EQ(reinterpret_cast<void*>(100), register_state.pc);
}
// Creates a fake stack with two JS frames on top of a C++ frame and checks that
// the unwinder correctly unwinds past the JS frames and returns the C++ frame's
// details.
TEST(Unwind_TwoJSFrames_Success) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
// Use a fake code range so that we can initialize it to 0s.
const size_t code_length = 40;
uintptr_t code[code_length] = {0};
unwind_state.code_range.start = code;
unwind_state.code_range.length_in_bytes = code_length * sizeof(uintptr_t);
// Our fake stack has three frames - one C++ frame and two JS frames (on top).
// The stack grows from high addresses to low addresses.
uintptr_t stack[10];
void* stack_base = stack + arraysize(stack);
stack[0] = 101;
stack[1] = 111;
stack[2] = reinterpret_cast<uintptr_t>(stack + 5); // saved FP (rbp).
// The fake return address is in the JS code range.
stack[3] = reinterpret_cast<uintptr_t>(code + 10);
stack[4] = 141;
stack[5] = reinterpret_cast<uintptr_t>(stack + 9); // saved FP (rbp).
stack[6] = 100; // Return address into C++ code.
stack[7] = 303; // The SP points here in the caller's frame.
stack[8] = 404;
stack[9] = 505;
register_state.sp = stack;
register_state.fp = stack + 2;
// Put the current PC inside of the code range so it looks valid.
register_state.pc = code + 30;
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
CHECK(unwound);
CHECK_EQ(reinterpret_cast<void*>(stack + 9), register_state.fp);
CHECK_EQ(reinterpret_cast<void*>(stack + 7), register_state.sp);
CHECK_EQ(reinterpret_cast<void*>(100), register_state.pc);
}
// If the PC is in JSEntry then the frame might not be set up correctly, meaning
// we can't unwind the stack properly.
TEST(Unwind_JSEntry_Fail) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
Code js_entry = i_isolate->heap()->builtin(Builtins::kJSEntry);
byte* start = reinterpret_cast<byte*>(js_entry.InstructionStart());
register_state.pc = start + 10;
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
unlimited_stack_base);
CHECK(!unwound);
// The register state should not change when unwinding fails.
CHECK_NULL(register_state.fp);
CHECK_NULL(register_state.sp);
CHECK_EQ(start + 10, register_state.pc);
}
TEST(Unwind_StackBounds_Basic) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
const size_t code_length = 10;
uintptr_t code[code_length] = {0};
unwind_state.code_range.start = code;
unwind_state.code_range.length_in_bytes = code_length * sizeof(uintptr_t);
uintptr_t stack[3];
stack[0] = reinterpret_cast<uintptr_t>(stack + 2); // saved FP (rbp).
stack[1] = 202; // Return address into C++ code.
stack[2] = 303; // The SP points here in the caller's frame.
register_state.sp = stack;
register_state.fp = stack;
register_state.pc = code;
void* wrong_stack_base = reinterpret_cast<void*>(
reinterpret_cast<uintptr_t>(stack) - sizeof(uintptr_t));
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
wrong_stack_base);
CHECK(!unwound);
// Correct the stack base and unwinding should succeed.
void* correct_stack_base = stack + arraysize(stack);
unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
correct_stack_base);
CHECK(unwound);
}
TEST(Unwind_StackBounds_WithUnwinding) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
UnwindState unwind_state = isolate->GetUnwindState();
RegisterState register_state;
// Use a fake code range so that we can initialize it to 0s.
const size_t code_length = 40;
uintptr_t code[code_length] = {0};
unwind_state.code_range.start = code;
unwind_state.code_range.length_in_bytes = code_length * sizeof(uintptr_t);
// Our fake stack has two frames - one C++ frame and one JS frame (on top).
// The stack grows from high addresses to low addresses.
uintptr_t stack[11];
void* stack_base = stack + arraysize(stack);
stack[0] = 101;
stack[1] = 111;
stack[2] = 121;
stack[3] = 131;
stack[4] = 141;
stack[5] = reinterpret_cast<uintptr_t>(stack + 9); // saved FP (rbp).
stack[6] = reinterpret_cast<uintptr_t>(code + 20); // JS code.
stack[7] = 303; // The SP points here in the caller's frame.
stack[8] = 404;
stack[9] = reinterpret_cast<uintptr_t>(stack) +
(12 * sizeof(uintptr_t)); // saved FP (OOB).
stack[10] = reinterpret_cast<uintptr_t>(code + 20); // JS code.
register_state.sp = stack;
register_state.fp = stack + 5;
// Put the current PC inside of the code range so it looks valid.
register_state.pc = code + 30;
// Unwind will fail because stack[9] FP points outside of the stack.
bool unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
CHECK(!unwound);
// Change the return address so that it is not in range. We will not range
// check the stack[9] FP value because we have finished unwinding and the
// contents of rbp does not necessarily have to be the FP in this case.
stack[10] = 202;
unwound = v8::Unwinder::TryUnwindV8Frames(unwind_state, &register_state,
stack_base);
CHECK(unwound);
}
TEST(PCIsInV8_BadState_Fail) {
UnwindState unwind_state;
void* pc = nullptr;
CHECK(!v8::Unwinder::PCIsInV8(unwind_state, pc));
}
TEST(PCIsInV8_ValidStateNullPC_Fail) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
UnwindState unwind_state = isolate->GetUnwindState();
void* pc = nullptr;
CHECK(!v8::Unwinder::PCIsInV8(unwind_state, pc));
}
void TestRangeBoundaries(const UnwindState& unwind_state, byte* range_start,
size_t range_length) {
void* pc = range_start - 1;
CHECK(!v8::Unwinder::PCIsInV8(unwind_state, pc));
pc = range_start;
CHECK(v8::Unwinder::PCIsInV8(unwind_state, pc));
pc = range_start + 1;
CHECK(v8::Unwinder::PCIsInV8(unwind_state, pc));
pc = range_start + range_length - 1;
CHECK(v8::Unwinder::PCIsInV8(unwind_state, pc));
pc = range_start + range_length;
CHECK(!v8::Unwinder::PCIsInV8(unwind_state, pc));
pc = range_start + range_length + 1;
CHECK(!v8::Unwinder::PCIsInV8(unwind_state, pc));
}
TEST(PCIsInV8_InCodeOrEmbeddedRange) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
UnwindState unwind_state = isolate->GetUnwindState();
byte* code_range_start = const_cast<byte*>(
reinterpret_cast<const byte*>(unwind_state.code_range.start));
size_t code_range_length = unwind_state.code_range.length_in_bytes;
TestRangeBoundaries(unwind_state, code_range_start, code_range_length);
byte* embedded_range_start = const_cast<byte*>(
reinterpret_cast<const byte*>(unwind_state.embedded_code_range.start));
size_t embedded_range_length =
unwind_state.embedded_code_range.length_in_bytes;
TestRangeBoundaries(unwind_state, embedded_range_start,
embedded_range_length);
}
// PCIsInV8 doesn't check if the PC is in JSEntry directly. It's assumed that
// the CodeRange or EmbeddedCodeRange contain JSEntry.
TEST(PCIsInV8_InJSEntryRange) {
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
UnwindState unwind_state = isolate->GetUnwindState();
Code js_entry = i_isolate->heap()->builtin(Builtins::kJSEntry);
byte* start = reinterpret_cast<byte*>(js_entry.InstructionStart());
size_t length = js_entry.InstructionSize();
void* pc = start;
CHECK(v8::Unwinder::PCIsInV8(unwind_state, pc));
pc = start + 1;
CHECK(v8::Unwinder::PCIsInV8(unwind_state, pc));
pc = start + length - 1;
CHECK(v8::Unwinder::PCIsInV8(unwind_state, pc));
}
// Large code objects can be allocated in large object space. Check that this is
// inside the CodeRange.
TEST(PCIsInV8_LargeCodeObject) {
FLAG_allow_natives_syntax = true;
LocalContext env;
v8::Isolate* isolate = env->GetIsolate();
Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
HandleScope scope(i_isolate);
UnwindState unwind_state = isolate->GetUnwindState();
// Create a big function that ends up in CODE_LO_SPACE.
const int instruction_size = Page::kPageSize + 1;
STATIC_ASSERT(instruction_size > kMaxRegularHeapObjectSize);
std::unique_ptr<byte[]> instructions(new byte[instruction_size]);
CodeDesc desc;
desc.buffer = instructions.get();
desc.buffer_size = instruction_size;
desc.instr_size = instruction_size;
desc.reloc_size = 0;
desc.constant_pool_size = 0;
desc.unwinding_info = nullptr;
desc.unwinding_info_size = 0;
desc.origin = nullptr;
Handle<Code> foo_code =
Factory::CodeBuilder(i_isolate, desc, Code::WASM_FUNCTION).Build();
CHECK(i_isolate->heap()->InSpace(*foo_code, CODE_LO_SPACE));
byte* start = reinterpret_cast<byte*>(foo_code->InstructionStart());
void* pc = start;
CHECK(v8::Unwinder::PCIsInV8(unwind_state, pc));
}
} // namespace test_unwinder
} // namespace internal
} // namespace v8