Files
sdk/runtime/vm/code_descriptors.cc
T
Samir Jindel ecbea5a58e [vm/ffi] Implement FFI callbacks on AOT for ELF and Asm snapshots (excl. blobs).
To do this, we add writable data sections (currently uninitialzed) to ELF and Asm snapshots
and allow Instructions to have patchable relocations against (the start of) these sections.

Issue https://github.com/dart-lang/sdk/issues/37295 (see also for design & discussion).

Change-Id: If20bfa55776f4044aaa6bb8ea2101d2ada41842c
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-product-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-android-release-arm-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/110221
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2019-09-03 12:02:02 +00:00

698 lines
22 KiB
C++

// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "vm/code_descriptors.h"
#include "vm/compiler/compiler_state.h"
#include "vm/log.h"
namespace dart {
void DescriptorList::AddDescriptor(RawPcDescriptors::Kind kind,
intptr_t pc_offset,
intptr_t deopt_id,
TokenPosition token_pos,
intptr_t try_index) {
ASSERT((kind == RawPcDescriptors::kRuntimeCall) ||
(kind == RawPcDescriptors::kBSSRelocation) ||
(kind == RawPcDescriptors::kOther) || (deopt_id != DeoptId::kNone));
// When precompiling, we only use pc descriptors for exceptions and
// relocations.
if (!FLAG_precompiled_mode || try_index != -1 ||
kind == RawPcDescriptors::kBSSRelocation) {
int32_t merged_kind_try =
RawPcDescriptors::MergedKindTry::Encode(kind, try_index);
PcDescriptors::EncodeInteger(&encoded_data_, merged_kind_try);
PcDescriptors::EncodeInteger(&encoded_data_, pc_offset - prev_pc_offset);
prev_pc_offset = pc_offset;
if (!FLAG_precompiled_mode) {
PcDescriptors::EncodeInteger(&encoded_data_, deopt_id - prev_deopt_id);
PcDescriptors::EncodeInteger(&encoded_data_,
token_pos.value() - prev_token_pos);
prev_deopt_id = deopt_id;
prev_token_pos = token_pos.value();
}
}
}
RawPcDescriptors* DescriptorList::FinalizePcDescriptors(uword entry_point) {
if (encoded_data_.length() == 0) {
return Object::empty_descriptors().raw();
}
return PcDescriptors::New(&encoded_data_);
}
void StackMapTableBuilder::AddEntry(intptr_t pc_offset,
BitmapBuilder* bitmap,
intptr_t register_bit_count) {
stack_map_ = StackMap::New(pc_offset, bitmap, register_bit_count);
list_.Add(stack_map_, Heap::kOld);
}
bool StackMapTableBuilder::Verify() {
intptr_t num_entries = Length();
StackMap& map1 = StackMap::Handle();
StackMap& map2 = StackMap::Handle();
for (intptr_t i = 1; i < num_entries; i++) {
map1 = MapAt(i - 1);
map2 = MapAt(i);
// Ensure there are no duplicates and the entries are sorted.
if (map1.PcOffset() >= map2.PcOffset()) {
return false;
}
}
return true;
}
RawArray* StackMapTableBuilder::FinalizeStackMaps(const Code& code) {
ASSERT(Verify());
intptr_t num_entries = Length();
if (num_entries == 0) {
return Object::empty_array().raw();
}
return Array::MakeFixedLength(list_);
}
RawStackMap* StackMapTableBuilder::MapAt(intptr_t index) const {
StackMap& map = StackMap::Handle();
map ^= list_.At(index);
return map.raw();
}
RawExceptionHandlers* ExceptionHandlerList::FinalizeExceptionHandlers(
uword entry_point) const {
intptr_t num_handlers = Length();
if (num_handlers == 0) {
return Object::empty_exception_handlers().raw();
}
const ExceptionHandlers& handlers =
ExceptionHandlers::Handle(ExceptionHandlers::New(num_handlers));
for (intptr_t i = 0; i < num_handlers; i++) {
// Assert that every element in the array has been initialized.
if (list_[i].handler_types == NULL) {
// Unreachable handler, entry not computed.
// Initialize it to some meaningful value.
const bool has_catch_all = false;
// Check it is uninitialized.
ASSERT((list_[i].outer_try_index == -1) &&
(list_[i].pc_offset == ExceptionHandlers::kInvalidPcOffset));
handlers.SetHandlerInfo(i, list_[i].outer_try_index, list_[i].pc_offset,
list_[i].needs_stacktrace, has_catch_all,
list_[i].token_pos, list_[i].is_generated);
handlers.SetHandledTypes(i, Array::empty_array());
} else {
const bool has_catch_all = ContainsDynamic(*list_[i].handler_types);
handlers.SetHandlerInfo(i, list_[i].outer_try_index, list_[i].pc_offset,
list_[i].needs_stacktrace, has_catch_all,
list_[i].token_pos, list_[i].is_generated);
handlers.SetHandledTypes(i, *list_[i].handler_types);
}
}
return handlers.raw();
}
static uint8_t* ZoneAllocator(uint8_t* ptr,
intptr_t old_size,
intptr_t new_size) {
Zone* zone = Thread::Current()->zone();
return zone->Realloc<uint8_t>(ptr, old_size, new_size);
}
#if !defined(DART_PRECOMPILED_RUNTIME)
class CatchEntryMovesMapBuilder::TrieNode : public ZoneAllocated {
public:
TrieNode() : move_(), entry_state_offset_(-1) {}
TrieNode(CatchEntryMove move, intptr_t index)
: move_(move), entry_state_offset_(index) {}
intptr_t Offset() { return entry_state_offset_; }
TrieNode* Insert(TrieNode* node) {
children_.Add(node);
return node;
}
TrieNode* Follow(CatchEntryMove next) {
for (intptr_t i = 0; i < children_.length(); i++) {
if (children_[i]->move_ == next) return children_[i];
}
return NULL;
}
private:
CatchEntryMove move_;
const intptr_t entry_state_offset_;
GrowableArray<TrieNode*> children_;
};
CatchEntryMovesMapBuilder::CatchEntryMovesMapBuilder()
: zone_(Thread::Current()->zone()),
root_(new TrieNode()),
current_pc_offset_(0),
buffer_(NULL),
stream_(&buffer_, ZoneAllocator, 64) {}
void CatchEntryMovesMapBuilder::Append(const CatchEntryMove& move) {
moves_.Add(move);
}
void CatchEntryMovesMapBuilder::NewMapping(intptr_t pc_offset) {
moves_.Clear();
current_pc_offset_ = pc_offset;
}
void CatchEntryMovesMapBuilder::EndMapping() {
intptr_t suffix_length = 0;
TrieNode* suffix = root_;
// Find the largest common suffix, get the last node of the path.
for (intptr_t i = moves_.length() - 1; i >= 0; i--) {
TrieNode* n = suffix->Follow(moves_[i]);
if (n == NULL) break;
suffix_length++;
suffix = n;
}
intptr_t length = moves_.length() - suffix_length;
intptr_t current_offset = stream_.bytes_written();
typedef WriteStream::Raw<sizeof(intptr_t), intptr_t> Writer;
Writer::Write(&stream_, current_pc_offset_);
Writer::Write(&stream_, length);
Writer::Write(&stream_, suffix_length);
Writer::Write(&stream_, suffix->Offset());
// Write the unshared part, adding it to the trie.
TrieNode* node = suffix;
for (intptr_t i = length - 1; i >= 0; i--) {
moves_[i].WriteTo(&stream_);
TrieNode* child = new (zone_) TrieNode(moves_[i], current_offset);
node->Insert(child);
node = child;
}
}
RawTypedData* CatchEntryMovesMapBuilder::FinalizeCatchEntryMovesMap() {
TypedData& td = TypedData::Handle(TypedData::New(
kTypedDataInt8ArrayCid, stream_.bytes_written(), Heap::kOld));
NoSafepointScope no_safepoint;
uint8_t* dest = reinterpret_cast<uint8_t*>(td.DataAddr(0));
uint8_t* src = stream_.buffer();
for (intptr_t i = 0; i < stream_.bytes_written(); i++) {
dest[i] = src[i];
}
return td.raw();
}
#endif // !defined(DART_PRECOMPILED_RUNTIME)
const TokenPosition CodeSourceMapBuilder::kInitialPosition =
TokenPosition(TokenPosition::kDartCodeProloguePos);
CodeSourceMapBuilder::CodeSourceMapBuilder(
bool stack_traces_only,
const GrowableArray<intptr_t>& caller_inline_id,
const GrowableArray<TokenPosition>& inline_id_to_token_pos,
const GrowableArray<const Function*>& inline_id_to_function)
: buffered_pc_offset_(0),
buffered_inline_id_stack_(),
buffered_token_pos_stack_(),
written_pc_offset_(0),
written_inline_id_stack_(),
written_token_pos_stack_(),
caller_inline_id_(caller_inline_id),
inline_id_to_token_pos_(inline_id_to_token_pos),
inline_id_to_function_(inline_id_to_function),
inlined_functions_(
GrowableObjectArray::Handle(GrowableObjectArray::New(Heap::kOld))),
buffer_(NULL),
stream_(&buffer_, ZoneAllocator, 64),
stack_traces_only_(stack_traces_only) {
buffered_inline_id_stack_.Add(0);
buffered_token_pos_stack_.Add(kInitialPosition);
written_inline_id_stack_.Add(0);
written_token_pos_stack_.Add(kInitialPosition);
}
void CodeSourceMapBuilder::FlushBuffer() {
FlushBufferStack();
FlushBufferPosition();
FlushBufferPC();
}
void CodeSourceMapBuilder::FlushBufferStack() {
for (intptr_t i = buffered_inline_id_stack_.length() - 1; i >= 0; i--) {
intptr_t buffered_id = buffered_inline_id_stack_[i];
if (i < written_inline_id_stack_.length()) {
intptr_t written_id = written_inline_id_stack_[i];
if (buffered_id == written_id) {
// i is the top-most position where the buffered and written stack
// match.
while (written_inline_id_stack_.length() > i + 1) {
WritePop();
}
for (intptr_t j = i + 1; j < buffered_inline_id_stack_.length(); j++) {
TokenPosition buffered_pos = buffered_token_pos_stack_[j - 1];
TokenPosition written_pos = written_token_pos_stack_[j - 1];
if (buffered_pos != written_pos) {
WriteChangePosition(buffered_pos);
}
WritePush(buffered_inline_id_stack_[j]);
}
return;
}
}
}
UNREACHABLE();
}
void CodeSourceMapBuilder::FlushBufferPosition() {
ASSERT(buffered_token_pos_stack_.length() ==
written_token_pos_stack_.length());
intptr_t top = buffered_token_pos_stack_.length() - 1;
TokenPosition buffered_pos = buffered_token_pos_stack_[top];
TokenPosition written_pos = written_token_pos_stack_[top];
if (buffered_pos != written_pos) {
WriteChangePosition(buffered_pos);
}
}
void CodeSourceMapBuilder::FlushBufferPC() {
if (buffered_pc_offset_ != written_pc_offset_) {
WriteAdvancePC(buffered_pc_offset_ - written_pc_offset_);
}
}
void CodeSourceMapBuilder::StartInliningInterval(int32_t pc_offset,
intptr_t inline_id) {
if (buffered_inline_id_stack_.Last() == inline_id) {
// No change in function stack.
return;
}
if (inline_id == -1) {
// Basic blocking missing an inline_id.
return;
}
if (!stack_traces_only_) {
FlushBuffer();
}
// Find a minimal set of pops and pushes to bring us to the new function
// stack.
// Pop to a common ancestor.
intptr_t common_parent = inline_id;
while (!IsOnBufferedStack(common_parent)) {
common_parent = caller_inline_id_[common_parent];
}
while (buffered_inline_id_stack_.Last() != common_parent) {
BufferPop();
}
// Push to the new top-of-stack function.
GrowableArray<intptr_t> to_push;
intptr_t id = inline_id;
while (id != common_parent) {
to_push.Add(id);
id = caller_inline_id_[id];
}
for (intptr_t i = to_push.length() - 1; i >= 0; i--) {
intptr_t callee_id = to_push[i];
TokenPosition call_token;
if (callee_id != 0) {
// TODO(rmacnak): Should make this array line up with the others.
call_token = inline_id_to_token_pos_[callee_id - 1];
} else {
UNREACHABLE();
}
// Report caller as at the position of the call.
BufferChangePosition(call_token);
BufferPush(callee_id);
}
}
void CodeSourceMapBuilder::BeginCodeSourceRange(int32_t pc_offset) {}
void CodeSourceMapBuilder::EndCodeSourceRange(int32_t pc_offset,
TokenPosition pos) {
if (pc_offset == buffered_pc_offset_) {
return; // Empty intermediate instruction.
}
if (pos != buffered_token_pos_stack_.Last()) {
if (!stack_traces_only_) {
FlushBuffer();
}
BufferChangePosition(pos);
}
BufferAdvancePC(pc_offset - buffered_pc_offset_);
}
void CodeSourceMapBuilder::NoteDescriptor(RawPcDescriptors::Kind kind,
int32_t pc_offset,
TokenPosition pos) {
const uint8_t kCanThrow =
RawPcDescriptors::kIcCall | RawPcDescriptors::kUnoptStaticCall |
RawPcDescriptors::kRuntimeCall | RawPcDescriptors::kOther;
if (stack_traces_only_ && ((kind & kCanThrow) != 0)) {
BufferChangePosition(pos);
BufferAdvancePC(pc_offset - buffered_pc_offset_);
FlushBuffer();
}
}
void CodeSourceMapBuilder::NoteNullCheck(int32_t pc_offset,
TokenPosition pos,
intptr_t name_index) {
BufferChangePosition(pos);
BufferAdvancePC(pc_offset - buffered_pc_offset_);
FlushBuffer();
WriteNullCheck(name_index);
}
intptr_t CodeSourceMapBuilder::GetFunctionId(intptr_t inline_id) {
const Function& function = *inline_id_to_function_[inline_id];
for (intptr_t i = 0; i < inlined_functions_.Length(); i++) {
if (inlined_functions_.At(i) == function.raw()) {
return i;
}
}
RELEASE_ASSERT(!function.IsNull());
inlined_functions_.Add(function, Heap::kOld);
return inlined_functions_.Length() - 1;
}
RawArray* CodeSourceMapBuilder::InliningIdToFunction() {
if (inlined_functions_.Length() == 0) {
return Object::empty_array().raw();
}
return Array::MakeFixedLength(inlined_functions_);
}
RawCodeSourceMap* CodeSourceMapBuilder::Finalize() {
if (!stack_traces_only_) {
FlushBuffer();
}
intptr_t length = stream_.bytes_written();
const CodeSourceMap& map = CodeSourceMap::Handle(CodeSourceMap::New(length));
NoSafepointScope no_safepoint;
memmove(map.Data(), buffer_, length);
return map.raw();
}
void CodeSourceMapBuilder::WriteChangePosition(TokenPosition pos) {
stream_.Write<uint8_t>(kChangePosition);
if (FLAG_precompiled_mode) {
intptr_t line = -1;
intptr_t inline_id = buffered_inline_id_stack_.Last();
if (inline_id < inline_id_to_function_.length()) {
const Function* function = inline_id_to_function_[inline_id];
Script& script = Script::Handle(function->script());
line = script.GetTokenLineUsingLineStarts(pos.SourcePosition());
}
stream_.Write<int32_t>(static_cast<int32_t>(line));
} else {
stream_.Write<int32_t>(static_cast<int32_t>(pos.value()));
}
written_token_pos_stack_.Last() = pos;
}
void CodeSourceMapReader::GetInlinedFunctionsAt(
int32_t pc_offset,
GrowableArray<const Function*>* function_stack,
GrowableArray<TokenPosition>* token_positions) {
function_stack->Clear();
token_positions->Clear();
NoSafepointScope no_safepoint;
ReadStream stream(map_.Data(), map_.Length());
int32_t current_pc_offset = 0;
function_stack->Add(&root_);
token_positions->Add(CodeSourceMapBuilder::kInitialPosition);
while (stream.PendingBytes() > 0) {
uint8_t opcode = stream.Read<uint8_t>();
switch (opcode) {
case CodeSourceMapBuilder::kChangePosition: {
int32_t position = stream.Read<int32_t>();
(*token_positions)[token_positions->length() - 1] =
TokenPosition(position);
break;
}
case CodeSourceMapBuilder::kAdvancePC: {
int32_t delta = stream.Read<int32_t>();
current_pc_offset += delta;
if (current_pc_offset > pc_offset) {
return;
}
break;
}
case CodeSourceMapBuilder::kPushFunction: {
int32_t func = stream.Read<int32_t>();
function_stack->Add(
&Function::Handle(Function::RawCast(functions_.At(func))));
token_positions->Add(CodeSourceMapBuilder::kInitialPosition);
break;
}
case CodeSourceMapBuilder::kPopFunction: {
// We never pop the root function.
ASSERT(function_stack->length() > 1);
ASSERT(token_positions->length() > 1);
function_stack->RemoveLast();
token_positions->RemoveLast();
break;
}
case CodeSourceMapBuilder::kNullCheck: {
stream.Read<int32_t>();
break;
}
default:
UNREACHABLE();
}
}
}
#ifndef PRODUCT
void CodeSourceMapReader::PrintJSONInlineIntervals(JSONObject* jsobj) {
{
JSONArray inlined_functions(jsobj, "_inlinedFunctions");
Function& function = Function::Handle();
for (intptr_t i = 0; i < functions_.Length(); i++) {
function ^= functions_.At(i);
ASSERT(!function.IsNull());
inlined_functions.AddValue(function);
}
}
GrowableArray<intptr_t> function_stack;
JSONArray inline_intervals(jsobj, "_inlinedIntervals");
NoSafepointScope no_safepoint;
ReadStream stream(map_.Data(), map_.Length());
int32_t current_pc_offset = 0;
function_stack.Add(0);
while (stream.PendingBytes() > 0) {
uint8_t opcode = stream.Read<uint8_t>();
switch (opcode) {
case CodeSourceMapBuilder::kChangePosition: {
stream.Read<int32_t>();
break;
}
case CodeSourceMapBuilder::kAdvancePC: {
int32_t delta = stream.Read<int32_t>();
// Format: [start, end, inline functions...]
JSONArray inline_interval(&inline_intervals);
inline_interval.AddValue(static_cast<intptr_t>(current_pc_offset));
inline_interval.AddValue(
static_cast<intptr_t>(current_pc_offset + delta - 1));
for (intptr_t i = 0; i < function_stack.length(); i++) {
inline_interval.AddValue(function_stack[i]);
}
current_pc_offset += delta;
break;
}
case CodeSourceMapBuilder::kPushFunction: {
int32_t func = stream.Read<int32_t>();
function_stack.Add(func);
break;
}
case CodeSourceMapBuilder::kPopFunction: {
// We never pop the root function.
ASSERT(function_stack.length() > 1);
function_stack.RemoveLast();
break;
}
case CodeSourceMapBuilder::kNullCheck: {
stream.Read<int32_t>();
break;
}
default:
UNREACHABLE();
}
}
}
#endif // !PRODUCT
void CodeSourceMapReader::DumpInlineIntervals(uword start) {
GrowableArray<const Function*> function_stack;
LogBlock lb;
NoSafepointScope no_safepoint;
ReadStream stream(map_.Data(), map_.Length());
int32_t current_pc_offset = 0;
function_stack.Add(&root_);
THR_Print("Inline intervals {\n");
while (stream.PendingBytes() > 0) {
uint8_t opcode = stream.Read<uint8_t>();
switch (opcode) {
case CodeSourceMapBuilder::kChangePosition: {
stream.Read<int32_t>();
break;
}
case CodeSourceMapBuilder::kAdvancePC: {
int32_t delta = stream.Read<int32_t>();
THR_Print("%" Px "-%" Px ": ", start + current_pc_offset,
start + current_pc_offset + delta - 1);
for (intptr_t i = 0; i < function_stack.length(); i++) {
THR_Print("%s ", function_stack[i]->ToCString());
}
THR_Print("\n");
current_pc_offset += delta;
break;
}
case CodeSourceMapBuilder::kPushFunction: {
int32_t func = stream.Read<int32_t>();
function_stack.Add(
&Function::Handle(Function::RawCast(functions_.At(func))));
break;
}
case CodeSourceMapBuilder::kPopFunction: {
// We never pop the root function.
ASSERT(function_stack.length() > 1);
function_stack.RemoveLast();
break;
}
case CodeSourceMapBuilder::kNullCheck: {
stream.Read<int32_t>();
break;
}
default:
UNREACHABLE();
}
}
THR_Print("}\n");
}
void CodeSourceMapReader::DumpSourcePositions(uword start) {
GrowableArray<const Function*> function_stack;
GrowableArray<TokenPosition> token_positions;
LogBlock lb;
NoSafepointScope no_safepoint;
ReadStream stream(map_.Data(), map_.Length());
int32_t current_pc_offset = 0;
function_stack.Add(&root_);
token_positions.Add(CodeSourceMapBuilder::kInitialPosition);
THR_Print("Source positions {\n");
while (stream.PendingBytes() > 0) {
uint8_t opcode = stream.Read<uint8_t>();
switch (opcode) {
case CodeSourceMapBuilder::kChangePosition: {
int32_t position = stream.Read<int32_t>();
token_positions[token_positions.length() - 1] = TokenPosition(position);
break;
}
case CodeSourceMapBuilder::kAdvancePC: {
int32_t delta = stream.Read<int32_t>();
THR_Print("%" Px "-%" Px ": ", start + current_pc_offset,
start + current_pc_offset + delta - 1);
for (intptr_t i = 0; i < function_stack.length(); i++) {
THR_Print("%s@%" Pd " ", function_stack[i]->ToCString(),
token_positions[i].value());
}
THR_Print("\n");
current_pc_offset += delta;
break;
}
case CodeSourceMapBuilder::kPushFunction: {
int32_t func = stream.Read<int32_t>();
function_stack.Add(
&Function::Handle(Function::RawCast(functions_.At(func))));
token_positions.Add(CodeSourceMapBuilder::kInitialPosition);
break;
}
case CodeSourceMapBuilder::kPopFunction: {
// We never pop the root function.
ASSERT(function_stack.length() > 1);
ASSERT(token_positions.length() > 1);
function_stack.RemoveLast();
token_positions.RemoveLast();
break;
}
case CodeSourceMapBuilder::kNullCheck: {
const intptr_t name_index = stream.Read<int32_t>();
THR_Print("%" Px "-%" Px ": null check PP#%" Pd "\n",
start + current_pc_offset, start + current_pc_offset,
name_index);
break;
}
default:
UNREACHABLE();
}
}
THR_Print("}\n");
}
intptr_t CodeSourceMapReader::GetNullCheckNameIndexAt(int32_t pc_offset) {
NoSafepointScope no_safepoint;
ReadStream stream(map_.Data(), map_.Length());
int32_t current_pc_offset = 0;
while (stream.PendingBytes() > 0) {
uint8_t opcode = stream.Read<uint8_t>();
switch (opcode) {
case CodeSourceMapBuilder::kChangePosition: {
stream.Read<int32_t>();
break;
}
case CodeSourceMapBuilder::kAdvancePC: {
int32_t delta = stream.Read<int32_t>();
current_pc_offset += delta;
RELEASE_ASSERT(current_pc_offset <= pc_offset);
break;
}
case CodeSourceMapBuilder::kPushFunction: {
stream.Read<int32_t>();
break;
}
case CodeSourceMapBuilder::kPopFunction: {
break;
}
case CodeSourceMapBuilder::kNullCheck: {
const int32_t name_index = stream.Read<int32_t>();
if (current_pc_offset == pc_offset) {
return name_index;
}
break;
}
default:
UNREACHABLE();
}
}
UNREACHABLE();
return -1;
}
} // namespace dart