deps: V8: backport d259a9e2ead7

Original commit message:
[maglev] Add source position collection
This change adds support for collecting source positions in Maglev for
profiling. It wires a SourcePositionTableBuilder through the code
generator and uses the existing source positions from the graph
labeller.
Fixed: 436575053
Change-Id: I64fa1e8829b036e498fa1d756c996716d16fb2a8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/6897146
Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#102119}
Before this change Maglev attached an empty source position table to its
generated Code objects (set_empty_source_position_table()). As a result,
when profiling with `--perf-prof --interpreted-frames-native-stack`
(linux perf / samply), Maglev-optimized frames carried no line/inlining
information in the jitdump, so inlined call chains were lost in the
resulting flamegraphs (baseline and TurboFan code were unaffected). This
backport restores per-pc source positions for Maglev code, matching V8
>= 15.x and newer Node.js.
The change is gated on collect_source_positions() (enabled by
--detailed-line-info / profiling); the steady-state generated machine
code is unchanged and there is no extra cost when not profiling.
Adaptations for V8 13.6 (node): the graph-labeller creation in
MaglevCompiler::Compile is added as a separate condition because node's
13.6 tree creates the labeller in a differently-shaped block than
upstream; the rest is a direct cherry-pick.
Refs: v8/v8@d259a9eFixes: #63816
PR-URL: #63865
Co-authored-by: Guillaume Lagrange <guillaume@codspeed.io>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>

Author: 2 people

common.gypi

@@ -42,7 +42,7 @@
 
 # Reset this number to 0 on major V8 upgrades.
 # Increment by one for each non-official patch applied to deps/v8.
-'v8_embedder_string': '-node.52',
+'v8_embedder_string': '-node.53',
 
 ##### V8 defaults for Node.js #####
 

deps/v8/src/maglev/maglev-code-gen-state.h

@@ -9,6 +9,7 @@
 #include"src/codegen/label.h"
 #include"src/codegen/machine-type.h"
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/compiler/backend/instruction.h"
 #include"src/compiler/js-heap-broker.h"
@@ -34,9 +35,11 @@ class MaglevCodeGenState {
 public:
 MaglevCodeGenState(MaglevCompilationInfo* compilation_info,
  MaglevSafepointTableBuilder* safepoint_table_builder,
+ SourcePositionTableBuilder* source_position_table_builder,
 uint32_t max_block_id)
  : compilation_info_(compilation_info),
 safepoint_table_builder_(safepoint_table_builder),
+ source_position_table_builder_(source_position_table_builder),
  real_jump_target_(max_block_id) {}
 
 voidset_tagged_slots(int slots) { tagged_slots_ = slots; }
@@ -80,6 +83,9 @@ class MaglevCodeGenState {
  MaglevSafepointTableBuilder* safepoint_table_builder() const {
 return safepoint_table_builder_;
  }
+ SourcePositionTableBuilder* source_position_table_builder() const {
+return source_position_table_builder_;
+ }
  MaglevCompilationInfo* compilation_info() const { return compilation_info_; }
 
  Label* entry_label() { return &entry_label_; }
@@ -121,6 +127,7 @@ class MaglevCodeGenState {
 private:
  MaglevCompilationInfo* const compilation_info_;
  MaglevSafepointTableBuilder* const safepoint_table_builder_;
+ SourcePositionTableBuilder* const source_position_table_builder_;
 
  std::vector<DeferredCodeInfo*> deferred_code_;
  std::vector<EagerDeoptInfo*> eager_deopts_;

deps/v8/src/maglev/maglev-code-generator.cc

@@ -707,7 +707,14 @@ class ExceptionHandlerTrampolineBuilder {
 classMaglevCodeGeneratingNodeProcessor {
 public:
 MaglevCodeGeneratingNodeProcessor(MaglevAssembler* masm, Zone* zone)
- : masm_(masm), zone_(zone) {}
+ : masm_(masm),
+zone_(zone),
+// Cache for faster check.
+ collect_source_positions_(masm->code_gen_state()
+ ->compilation_info()
+ ->collect_source_positions()) {
+DCHECK_IMPLIES(collect_source_positions_, graph_labeller() != nullptr);
+ }
 
 voidPreProcessGraph(Graph* graph) {
 // TODO(victorgomes): I wonder if we want to create a struct that shares
@@ -800,6 +807,15 @@ class MaglevCodeGeneratingNodeProcessor {
  << PrintNode(graph_labeller(), node);
  __ RecordComment(ss.str());
  }
+if (collect_source_positions_) {
+// TODO(leszeks): Consider collecting source position in a more memory
+// friendly way, if we don't need the whole graph labeller.
+constauto& provenance = graph_labeller()->GetNodeProvenance(node);
+if (provenance.position.IsKnown()) {
+code_gen_state()->source_position_table_builder()->AddPosition(
+ masm_->pc_offset(), provenance.position, false);
+ }
+ }
 
 if (v8_flags.maglev_assert_stack_size) {
  __ AssertStackSizeCorrect();
@@ -1105,6 +1121,7 @@ class MaglevCodeGeneratingNodeProcessor {
  }
  MaglevAssembler* const masm_;
  Zone* zone_;
+bool collect_source_positions_;
 };
 
 classSafepointingNodeProcessor {
@@ -1695,8 +1712,9 @@ MaglevCodeGenerator::MaglevCodeGenerator(
  safepoint_table_builder_(compilation_info->zone(),
  graph->tagged_stack_slots()),
  frame_translation_builder_(compilation_info->zone()),
+ source_position_table_builder_(compilation_info->zone()),
  code_gen_state_(compilation_info, &safepoint_table_builder_,
- graph->max_block_id()),
+&source_position_table_builder_, graph->max_block_id()),
  masm_(isolate->GetMainThreadIsolateUnsafe(), compilation_info->zone(),
  &code_gen_state_),
  graph_(graph),
@@ -1919,6 +1937,10 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  LocalIsolate* local_isolate) {
 if (!code_gen_succeeded_) return {};
 
+// Allocate the source position table.
+ Handle<TrustedByteArray> source_positions =
+ source_position_table_builder_.ToSourcePositionTable(local_isolate);
+
  Handle<DeoptimizationData> deopt_data =
  (v8_flags.maglev_deopt_data_on_background &&
  !v8_flags.maglev_build_code_on_background)
@@ -1934,7 +1956,7 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  .set_stack_slots(stack_slot_count_with_fixed_frame())
  .set_parameter_count(parameter_count())
  .set_deoptimization_data(deopt_data)
- .set_empty_source_position_table()
+ .set_source_position_table(source_positions)
  .set_inlined_bytecode_size(graph_->total_inlined_bytecode_size())
  .set_osr_offset(
  code_gen_state_.compilation_info()->toplevel_osr_offset());

deps/v8/src/maglev/maglev-code-generator.h

@@ -6,6 +6,7 @@
 #defineV8_MAGLEV_MAGLEV_CODE_GENERATOR_H_
 
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/deoptimizer/frame-translation-builder.h"
 #include"src/maglev/maglev-assembler.h"
@@ -54,6 +55,7 @@ class MaglevCodeGenerator final {
  LocalIsolate* local_isolate_;
  MaglevSafepointTableBuilder safepoint_table_builder_;
  FrameTranslationBuilder frame_translation_builder_;
+ SourcePositionTableBuilder source_position_table_builder_;
  MaglevCodeGenState code_gen_state_;
  MaglevAssembler masm_;
  Graph* const graph_;

deps/v8/src/maglev/maglev-compiler.cc

@@ -82,6 +82,18 @@ bool MaglevCompiler::Compile(LocalIsolate* local_isolate,
  compilation_info->set_graph_labeller(newMaglevGraphLabeller());
  }
 
+// When collecting source positions for profiling, create a graph labeller
+// so per-node provenance (including inlined positions) is recorded during
+// graph building and a real source position table can be attached to the
+// Code object.
+// Upstream V8 folds this into the single graph-labeller condition; node's
+// V8 creates the labeller in a differently-shaped block, so the condition
+// is added separately here.
+if (compilation_info->collect_source_positions() &&
+ !compilation_info->has_graph_labeller()) {
+ compilation_info->set_graph_labeller(newMaglevGraphLabeller());
+ }
+
 if (is_tracing_enabled &&
  (v8_flags.print_maglev_code || v8_flags.print_maglev_graph ||
  v8_flags.print_maglev_graphs || v8_flags.trace_maglev_graph_building ||

deps/v8/test/unittests/maglev/maglev-assembler-unittest.cc

@@ -18,7 +18,7 @@ class MaglevAssemblerTest : public MaglevTest {
 public:
 MaglevAssemblerTest()
  : MaglevTest(),
-codegen_state(nullptr, nullptr, 0),
+codegen_state(nullptr, nullptr, nullptr, 0),
  as(isolate(), zone(), &codegen_state) {}
 
 voidFinalizeAndRun(Label* pass, Label* fail) {

common.gypi

@@ -42,7 +42,7 @@
 
 # Reset this number to 0 on major V8 upgrades.
 # Increment by one for each non-official patch applied to deps/v8.
-'v8_embedder_string': '-node.52',
+'v8_embedder_string': '-node.53',
 
 ##### V8 defaults for Node.js #####
 

deps/v8/src/maglev/maglev-code-gen-state.h

@@ -9,6 +9,7 @@
 #include"src/codegen/label.h"
 #include"src/codegen/machine-type.h"
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/compiler/backend/instruction.h"
 #include"src/compiler/js-heap-broker.h"
@@ -34,9 +35,11 @@ class MaglevCodeGenState {
 public:
 MaglevCodeGenState(MaglevCompilationInfo* compilation_info,
  MaglevSafepointTableBuilder* safepoint_table_builder,
+ SourcePositionTableBuilder* source_position_table_builder,
 uint32_t max_block_id)
  : compilation_info_(compilation_info),
 safepoint_table_builder_(safepoint_table_builder),
+ source_position_table_builder_(source_position_table_builder),
  real_jump_target_(max_block_id) {}
 
 voidset_tagged_slots(int slots) { tagged_slots_ = slots; }
@@ -80,6 +83,9 @@ class MaglevCodeGenState {
  MaglevSafepointTableBuilder* safepoint_table_builder() const {
 return safepoint_table_builder_;
  }
+ SourcePositionTableBuilder* source_position_table_builder() const {
+return source_position_table_builder_;
+ }
  MaglevCompilationInfo* compilation_info() const { return compilation_info_; }
 
  Label* entry_label() { return &entry_label_; }
@@ -121,6 +127,7 @@ class MaglevCodeGenState {
 private:
  MaglevCompilationInfo* const compilation_info_;
  MaglevSafepointTableBuilder* const safepoint_table_builder_;
+ SourcePositionTableBuilder* const source_position_table_builder_;
 
  std::vector<DeferredCodeInfo*> deferred_code_;
  std::vector<EagerDeoptInfo*> eager_deopts_;

deps/v8/src/maglev/maglev-code-generator.cc

@@ -707,7 +707,14 @@ class ExceptionHandlerTrampolineBuilder {
 classMaglevCodeGeneratingNodeProcessor {
 public:
 MaglevCodeGeneratingNodeProcessor(MaglevAssembler* masm, Zone* zone)
- : masm_(masm), zone_(zone) {}
+ : masm_(masm),
+zone_(zone),
+// Cache for faster check.
+ collect_source_positions_(masm->code_gen_state()
+ ->compilation_info()
+ ->collect_source_positions()) {
+DCHECK_IMPLIES(collect_source_positions_, graph_labeller() != nullptr);
+ }
 
 voidPreProcessGraph(Graph* graph) {
 // TODO(victorgomes): I wonder if we want to create a struct that shares
@@ -800,6 +807,15 @@ class MaglevCodeGeneratingNodeProcessor {
  << PrintNode(graph_labeller(), node);
  __ RecordComment(ss.str());
  }
+if (collect_source_positions_) {
+// TODO(leszeks): Consider collecting source position in a more memory
+// friendly way, if we don't need the whole graph labeller.
+constauto& provenance = graph_labeller()->GetNodeProvenance(node);
+if (provenance.position.IsKnown()) {
+code_gen_state()->source_position_table_builder()->AddPosition(
+ masm_->pc_offset(), provenance.position, false);
+ }
+ }
 
 if (v8_flags.maglev_assert_stack_size) {
  __ AssertStackSizeCorrect();
@@ -1105,6 +1121,7 @@ class MaglevCodeGeneratingNodeProcessor {
  }
  MaglevAssembler* const masm_;
  Zone* zone_;
+bool collect_source_positions_;
 };
 
 classSafepointingNodeProcessor {
@@ -1695,8 +1712,9 @@ MaglevCodeGenerator::MaglevCodeGenerator(
  safepoint_table_builder_(compilation_info->zone(),
  graph->tagged_stack_slots()),
  frame_translation_builder_(compilation_info->zone()),
+ source_position_table_builder_(compilation_info->zone()),
  code_gen_state_(compilation_info, &safepoint_table_builder_,
- graph->max_block_id()),
+&source_position_table_builder_, graph->max_block_id()),
  masm_(isolate->GetMainThreadIsolateUnsafe(), compilation_info->zone(),
  &code_gen_state_),
  graph_(graph),
@@ -1919,6 +1937,10 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  LocalIsolate* local_isolate) {
 if (!code_gen_succeeded_) return {};
 
+// Allocate the source position table.
+ Handle<TrustedByteArray> source_positions =
+ source_position_table_builder_.ToSourcePositionTable(local_isolate);
+
  Handle<DeoptimizationData> deopt_data =
  (v8_flags.maglev_deopt_data_on_background &&
  !v8_flags.maglev_build_code_on_background)
@@ -1934,7 +1956,7 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  .set_stack_slots(stack_slot_count_with_fixed_frame())
  .set_parameter_count(parameter_count())
  .set_deoptimization_data(deopt_data)
- .set_empty_source_position_table()
+ .set_source_position_table(source_positions)
  .set_inlined_bytecode_size(graph_->total_inlined_bytecode_size())
  .set_osr_offset(
  code_gen_state_.compilation_info()->toplevel_osr_offset());

deps/v8/src/maglev/maglev-code-generator.h

@@ -6,6 +6,7 @@
 #defineV8_MAGLEV_MAGLEV_CODE_GENERATOR_H_
 
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/deoptimizer/frame-translation-builder.h"
 #include"src/maglev/maglev-assembler.h"
@@ -54,6 +55,7 @@ class MaglevCodeGenerator final {
  LocalIsolate* local_isolate_;
  MaglevSafepointTableBuilder safepoint_table_builder_;
  FrameTranslationBuilder frame_translation_builder_;
+ SourcePositionTableBuilder source_position_table_builder_;
  MaglevCodeGenState code_gen_state_;
  MaglevAssembler masm_;
  Graph* const graph_;

deps/v8/src/maglev/maglev-compiler.cc

@@ -82,6 +82,18 @@ bool MaglevCompiler::Compile(LocalIsolate* local_isolate,
  compilation_info->set_graph_labeller(newMaglevGraphLabeller());
  }
 
+// When collecting source positions for profiling, create a graph labeller
+// so per-node provenance (including inlined positions) is recorded during
+// graph building and a real source position table can be attached to the
+// Code object.
+// Upstream V8 folds this into the single graph-labeller condition; node's
+// V8 creates the labeller in a differently-shaped block, so the condition
+// is added separately here.
+if (compilation_info->collect_source_positions() &&
+ !compilation_info->has_graph_labeller()) {
+ compilation_info->set_graph_labeller(newMaglevGraphLabeller());
+ }
+
 if (is_tracing_enabled &&
  (v8_flags.print_maglev_code || v8_flags.print_maglev_graph ||
  v8_flags.print_maglev_graphs || v8_flags.trace_maglev_graph_building ||

deps/v8/test/unittests/maglev/maglev-assembler-unittest.cc

@@ -18,7 +18,7 @@ class MaglevAssemblerTest : public MaglevTest {
 public:
 MaglevAssemblerTest()
  : MaglevTest(),
-codegen_state(nullptr, nullptr, 0),
+codegen_state(nullptr, nullptr, nullptr, 0),
  as(isolate(), zone(), &codegen_state) {}
 
 voidFinalizeAndRun(Label* pass, Label* fail) {

common.gypi

@@ -42,7 +42,7 @@
 
 # Reset this number to 0 on major V8 upgrades.
 # Increment by one for each non-official patch applied to deps/v8.
-'v8_embedder_string': '-node.52',
+'v8_embedder_string': '-node.53',
 
 ##### V8 defaults for Node.js #####
 

deps/v8/src/maglev/maglev-code-gen-state.h

@@ -9,6 +9,7 @@
 #include"src/codegen/label.h"
 #include"src/codegen/machine-type.h"
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/compiler/backend/instruction.h"
 #include"src/compiler/js-heap-broker.h"
@@ -34,9 +35,11 @@ class MaglevCodeGenState {
 public:
 MaglevCodeGenState(MaglevCompilationInfo* compilation_info,
  MaglevSafepointTableBuilder* safepoint_table_builder,
+ SourcePositionTableBuilder* source_position_table_builder,
 uint32_t max_block_id)
  : compilation_info_(compilation_info),
 safepoint_table_builder_(safepoint_table_builder),
+ source_position_table_builder_(source_position_table_builder),
  real_jump_target_(max_block_id) {}
 
 voidset_tagged_slots(int slots) { tagged_slots_ = slots; }
@@ -80,6 +83,9 @@ class MaglevCodeGenState {
  MaglevSafepointTableBuilder* safepoint_table_builder() const {
 return safepoint_table_builder_;
  }
+ SourcePositionTableBuilder* source_position_table_builder() const {
+return source_position_table_builder_;
+ }
  MaglevCompilationInfo* compilation_info() const { return compilation_info_; }
 
  Label* entry_label() { return &entry_label_; }
@@ -121,6 +127,7 @@ class MaglevCodeGenState {
 private:
  MaglevCompilationInfo* const compilation_info_;
  MaglevSafepointTableBuilder* const safepoint_table_builder_;
+ SourcePositionTableBuilder* const source_position_table_builder_;
 
  std::vector<DeferredCodeInfo*> deferred_code_;
  std::vector<EagerDeoptInfo*> eager_deopts_;

deps/v8/src/maglev/maglev-code-generator.cc

@@ -707,7 +707,14 @@ class ExceptionHandlerTrampolineBuilder {
 classMaglevCodeGeneratingNodeProcessor {
 public:
 MaglevCodeGeneratingNodeProcessor(MaglevAssembler* masm, Zone* zone)
- : masm_(masm), zone_(zone) {}
+ : masm_(masm),
+zone_(zone),
+// Cache for faster check.
+ collect_source_positions_(masm->code_gen_state()
+ ->compilation_info()
+ ->collect_source_positions()) {
+DCHECK_IMPLIES(collect_source_positions_, graph_labeller() != nullptr);
+ }
 
 voidPreProcessGraph(Graph* graph) {
 // TODO(victorgomes): I wonder if we want to create a struct that shares
@@ -800,6 +807,15 @@ class MaglevCodeGeneratingNodeProcessor {
  << PrintNode(graph_labeller(), node);
  __ RecordComment(ss.str());
  }
+if (collect_source_positions_) {
+// TODO(leszeks): Consider collecting source position in a more memory
+// friendly way, if we don't need the whole graph labeller.
+constauto& provenance = graph_labeller()->GetNodeProvenance(node);
+if (provenance.position.IsKnown()) {
+code_gen_state()->source_position_table_builder()->AddPosition(
+ masm_->pc_offset(), provenance.position, false);
+ }
+ }
 
 if (v8_flags.maglev_assert_stack_size) {
  __ AssertStackSizeCorrect();
@@ -1105,6 +1121,7 @@ class MaglevCodeGeneratingNodeProcessor {
  }
  MaglevAssembler* const masm_;
  Zone* zone_;
+bool collect_source_positions_;
 };
 
 classSafepointingNodeProcessor {
@@ -1695,8 +1712,9 @@ MaglevCodeGenerator::MaglevCodeGenerator(
  safepoint_table_builder_(compilation_info->zone(),
  graph->tagged_stack_slots()),
  frame_translation_builder_(compilation_info->zone()),
+ source_position_table_builder_(compilation_info->zone()),
  code_gen_state_(compilation_info, &safepoint_table_builder_,
- graph->max_block_id()),
+&source_position_table_builder_, graph->max_block_id()),
  masm_(isolate->GetMainThreadIsolateUnsafe(), compilation_info->zone(),
  &code_gen_state_),
  graph_(graph),
@@ -1919,6 +1937,10 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  LocalIsolate* local_isolate) {
 if (!code_gen_succeeded_) return {};
 
+// Allocate the source position table.
+ Handle<TrustedByteArray> source_positions =
+ source_position_table_builder_.ToSourcePositionTable(local_isolate);
+
  Handle<DeoptimizationData> deopt_data =
  (v8_flags.maglev_deopt_data_on_background &&
  !v8_flags.maglev_build_code_on_background)
@@ -1934,7 +1956,7 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  .set_stack_slots(stack_slot_count_with_fixed_frame())
  .set_parameter_count(parameter_count())
  .set_deoptimization_data(deopt_data)
- .set_empty_source_position_table()
+ .set_source_position_table(source_positions)
  .set_inlined_bytecode_size(graph_->total_inlined_bytecode_size())
  .set_osr_offset(
  code_gen_state_.compilation_info()->toplevel_osr_offset());

deps/v8/src/maglev/maglev-code-generator.h

@@ -6,6 +6,7 @@
 #defineV8_MAGLEV_MAGLEV_CODE_GENERATOR_H_
 
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/deoptimizer/frame-translation-builder.h"
 #include"src/maglev/maglev-assembler.h"
@@ -54,6 +55,7 @@ class MaglevCodeGenerator final {
  LocalIsolate* local_isolate_;
  MaglevSafepointTableBuilder safepoint_table_builder_;
  FrameTranslationBuilder frame_translation_builder_;
+ SourcePositionTableBuilder source_position_table_builder_;
  MaglevCodeGenState code_gen_state_;
  MaglevAssembler masm_;
  Graph* const graph_;

deps/v8/src/maglev/maglev-compiler.cc

@@ -82,6 +82,18 @@ bool MaglevCompiler::Compile(LocalIsolate* local_isolate,
  compilation_info->set_graph_labeller(newMaglevGraphLabeller());
  }
 
+// When collecting source positions for profiling, create a graph labeller
+// so per-node provenance (including inlined positions) is recorded during
+// graph building and a real source position table can be attached to the
+// Code object.
+// Upstream V8 folds this into the single graph-labeller condition; node's
+// V8 creates the labeller in a differently-shaped block, so the condition
+// is added separately here.
+if (compilation_info->collect_source_positions() &&
+ !compilation_info->has_graph_labeller()) {
+ compilation_info->set_graph_labeller(newMaglevGraphLabeller());
+ }
+
 if (is_tracing_enabled &&
  (v8_flags.print_maglev_code || v8_flags.print_maglev_graph ||
  v8_flags.print_maglev_graphs || v8_flags.trace_maglev_graph_building ||

deps/v8/test/unittests/maglev/maglev-assembler-unittest.cc

@@ -18,7 +18,7 @@ class MaglevAssemblerTest : public MaglevTest {
 public:
 MaglevAssemblerTest()
  : MaglevTest(),
-codegen_state(nullptr, nullptr, 0),
+codegen_state(nullptr, nullptr, nullptr, 0),
  as(isolate(), zone(), &codegen_state) {}
 
 voidFinalizeAndRun(Label* pass, Label* fail) {

common.gypi

@@ -42,7 +42,7 @@
 
 # Reset this number to 0 on major V8 upgrades.
 # Increment by one for each non-official patch applied to deps/v8.
-'v8_embedder_string': '-node.52',
+'v8_embedder_string': '-node.53',
 
 ##### V8 defaults for Node.js #####
 

deps/v8/src/maglev/maglev-code-gen-state.h

@@ -9,6 +9,7 @@
 #include"src/codegen/label.h"
 #include"src/codegen/machine-type.h"
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/compiler/backend/instruction.h"
 #include"src/compiler/js-heap-broker.h"
@@ -34,9 +35,11 @@ class MaglevCodeGenState {
 public:
 MaglevCodeGenState(MaglevCompilationInfo* compilation_info,
  MaglevSafepointTableBuilder* safepoint_table_builder,
+ SourcePositionTableBuilder* source_position_table_builder,
 uint32_t max_block_id)
  : compilation_info_(compilation_info),
 safepoint_table_builder_(safepoint_table_builder),
+ source_position_table_builder_(source_position_table_builder),
  real_jump_target_(max_block_id) {}
 
 voidset_tagged_slots(int slots) { tagged_slots_ = slots; }
@@ -80,6 +83,9 @@ class MaglevCodeGenState {
  MaglevSafepointTableBuilder* safepoint_table_builder() const {
 return safepoint_table_builder_;
  }
+ SourcePositionTableBuilder* source_position_table_builder() const {
+return source_position_table_builder_;
+ }
  MaglevCompilationInfo* compilation_info() const { return compilation_info_; }
 
  Label* entry_label() { return &entry_label_; }
@@ -121,6 +127,7 @@ class MaglevCodeGenState {
 private:
  MaglevCompilationInfo* const compilation_info_;
  MaglevSafepointTableBuilder* const safepoint_table_builder_;
+ SourcePositionTableBuilder* const source_position_table_builder_;
 
  std::vector<DeferredCodeInfo*> deferred_code_;
  std::vector<EagerDeoptInfo*> eager_deopts_;

deps/v8/src/maglev/maglev-code-generator.cc

@@ -707,7 +707,14 @@ class ExceptionHandlerTrampolineBuilder {
 classMaglevCodeGeneratingNodeProcessor {
 public:
 MaglevCodeGeneratingNodeProcessor(MaglevAssembler* masm, Zone* zone)
- : masm_(masm), zone_(zone) {}
+ : masm_(masm),
+zone_(zone),
+// Cache for faster check.
+ collect_source_positions_(masm->code_gen_state()
+ ->compilation_info()
+ ->collect_source_positions()) {
+DCHECK_IMPLIES(collect_source_positions_, graph_labeller() != nullptr);
+ }
 
 voidPreProcessGraph(Graph* graph) {
 // TODO(victorgomes): I wonder if we want to create a struct that shares
@@ -800,6 +807,15 @@ class MaglevCodeGeneratingNodeProcessor {
  << PrintNode(graph_labeller(), node);
  __ RecordComment(ss.str());
  }
+if (collect_source_positions_) {
+// TODO(leszeks): Consider collecting source position in a more memory
+// friendly way, if we don't need the whole graph labeller.
+constauto& provenance = graph_labeller()->GetNodeProvenance(node);
+if (provenance.position.IsKnown()) {
+code_gen_state()->source_position_table_builder()->AddPosition(
+ masm_->pc_offset(), provenance.position, false);
+ }
+ }
 
 if (v8_flags.maglev_assert_stack_size) {
  __ AssertStackSizeCorrect();
@@ -1105,6 +1121,7 @@ class MaglevCodeGeneratingNodeProcessor {
  }
  MaglevAssembler* const masm_;
  Zone* zone_;
+bool collect_source_positions_;
 };
 
 classSafepointingNodeProcessor {
@@ -1695,8 +1712,9 @@ MaglevCodeGenerator::MaglevCodeGenerator(
  safepoint_table_builder_(compilation_info->zone(),
  graph->tagged_stack_slots()),
  frame_translation_builder_(compilation_info->zone()),
+ source_position_table_builder_(compilation_info->zone()),
  code_gen_state_(compilation_info, &safepoint_table_builder_,
- graph->max_block_id()),
+&source_position_table_builder_, graph->max_block_id()),
  masm_(isolate->GetMainThreadIsolateUnsafe(), compilation_info->zone(),
  &code_gen_state_),
  graph_(graph),
@@ -1919,6 +1937,10 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  LocalIsolate* local_isolate) {
 if (!code_gen_succeeded_) return {};
 
+// Allocate the source position table.
+ Handle<TrustedByteArray> source_positions =
+ source_position_table_builder_.ToSourcePositionTable(local_isolate);
+
  Handle<DeoptimizationData> deopt_data =
  (v8_flags.maglev_deopt_data_on_background &&
  !v8_flags.maglev_build_code_on_background)
@@ -1934,7 +1956,7 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  .set_stack_slots(stack_slot_count_with_fixed_frame())
  .set_parameter_count(parameter_count())
  .set_deoptimization_data(deopt_data)
- .set_empty_source_position_table()
+ .set_source_position_table(source_positions)
  .set_inlined_bytecode_size(graph_->total_inlined_bytecode_size())
  .set_osr_offset(
  code_gen_state_.compilation_info()->toplevel_osr_offset());

deps/v8/src/maglev/maglev-code-generator.h

@@ -6,6 +6,7 @@
 #defineV8_MAGLEV_MAGLEV_CODE_GENERATOR_H_
 
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/deoptimizer/frame-translation-builder.h"
 #include"src/maglev/maglev-assembler.h"
@@ -54,6 +55,7 @@ class MaglevCodeGenerator final {
  LocalIsolate* local_isolate_;
  MaglevSafepointTableBuilder safepoint_table_builder_;
  FrameTranslationBuilder frame_translation_builder_;
+ SourcePositionTableBuilder source_position_table_builder_;
  MaglevCodeGenState code_gen_state_;
  MaglevAssembler masm_;
  Graph* const graph_;

deps/v8/src/maglev/maglev-compiler.cc

@@ -82,6 +82,18 @@ bool MaglevCompiler::Compile(LocalIsolate* local_isolate,
  compilation_info->set_graph_labeller(newMaglevGraphLabeller());
  }
 
+// When collecting source positions for profiling, create a graph labeller
+// so per-node provenance (including inlined positions) is recorded during
+// graph building and a real source position table can be attached to the
+// Code object.
+// Upstream V8 folds this into the single graph-labeller condition; node's
+// V8 creates the labeller in a differently-shaped block, so the condition
+// is added separately here.
+if (compilation_info->collect_source_positions() &&
+ !compilation_info->has_graph_labeller()) {
+ compilation_info->set_graph_labeller(newMaglevGraphLabeller());
+ }
+
 if (is_tracing_enabled &&
  (v8_flags.print_maglev_code || v8_flags.print_maglev_graph ||
  v8_flags.print_maglev_graphs || v8_flags.trace_maglev_graph_building ||

deps/v8/test/unittests/maglev/maglev-assembler-unittest.cc

@@ -18,7 +18,7 @@ class MaglevAssemblerTest : public MaglevTest {
 public:
 MaglevAssemblerTest()
  : MaglevTest(),
-codegen_state(nullptr, nullptr, 0),
+codegen_state(nullptr, nullptr, nullptr, 0),
  as(isolate(), zone(), &codegen_state) {}
 
 voidFinalizeAndRun(Label* pass, Label* fail) {

common.gypi

@@ -42,7 +42,7 @@
 
 # Reset this number to 0 on major V8 upgrades.
 # Increment by one for each non-official patch applied to deps/v8.
-'v8_embedder_string': '-node.52',
+'v8_embedder_string': '-node.53',
 
 ##### V8 defaults for Node.js #####
 

deps/v8/src/maglev/maglev-code-gen-state.h

@@ -9,6 +9,7 @@
 #include"src/codegen/label.h"
 #include"src/codegen/machine-type.h"
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/compiler/backend/instruction.h"
 #include"src/compiler/js-heap-broker.h"
@@ -34,9 +35,11 @@ class MaglevCodeGenState {
 public:
 MaglevCodeGenState(MaglevCompilationInfo* compilation_info,
  MaglevSafepointTableBuilder* safepoint_table_builder,
+ SourcePositionTableBuilder* source_position_table_builder,
 uint32_t max_block_id)
  : compilation_info_(compilation_info),
 safepoint_table_builder_(safepoint_table_builder),
+ source_position_table_builder_(source_position_table_builder),
  real_jump_target_(max_block_id) {}
 
 voidset_tagged_slots(int slots) { tagged_slots_ = slots; }
@@ -80,6 +83,9 @@ class MaglevCodeGenState {
  MaglevSafepointTableBuilder* safepoint_table_builder() const {
 return safepoint_table_builder_;
  }
+ SourcePositionTableBuilder* source_position_table_builder() const {
+return source_position_table_builder_;
+ }
  MaglevCompilationInfo* compilation_info() const { return compilation_info_; }
 
  Label* entry_label() { return &entry_label_; }
@@ -121,6 +127,7 @@ class MaglevCodeGenState {
 private:
  MaglevCompilationInfo* const compilation_info_;
  MaglevSafepointTableBuilder* const safepoint_table_builder_;
+ SourcePositionTableBuilder* const source_position_table_builder_;
 
  std::vector<DeferredCodeInfo*> deferred_code_;
  std::vector<EagerDeoptInfo*> eager_deopts_;

deps/v8/src/maglev/maglev-code-generator.cc

@@ -707,7 +707,14 @@ class ExceptionHandlerTrampolineBuilder {
 classMaglevCodeGeneratingNodeProcessor {
 public:
 MaglevCodeGeneratingNodeProcessor(MaglevAssembler* masm, Zone* zone)
- : masm_(masm), zone_(zone) {}
+ : masm_(masm),
+zone_(zone),
+// Cache for faster check.
+ collect_source_positions_(masm->code_gen_state()
+ ->compilation_info()
+ ->collect_source_positions()) {
+DCHECK_IMPLIES(collect_source_positions_, graph_labeller() != nullptr);
+ }
 
 voidPreProcessGraph(Graph* graph) {
 // TODO(victorgomes): I wonder if we want to create a struct that shares
@@ -800,6 +807,15 @@ class MaglevCodeGeneratingNodeProcessor {
  << PrintNode(graph_labeller(), node);
  __ RecordComment(ss.str());
  }
+if (collect_source_positions_) {
+// TODO(leszeks): Consider collecting source position in a more memory
+// friendly way, if we don't need the whole graph labeller.
+constauto& provenance = graph_labeller()->GetNodeProvenance(node);
+if (provenance.position.IsKnown()) {
+code_gen_state()->source_position_table_builder()->AddPosition(
+ masm_->pc_offset(), provenance.position, false);
+ }
+ }
 
 if (v8_flags.maglev_assert_stack_size) {
  __ AssertStackSizeCorrect();
@@ -1105,6 +1121,7 @@ class MaglevCodeGeneratingNodeProcessor {
  }
  MaglevAssembler* const masm_;
  Zone* zone_;
+bool collect_source_positions_;
 };
 
 classSafepointingNodeProcessor {
@@ -1695,8 +1712,9 @@ MaglevCodeGenerator::MaglevCodeGenerator(
  safepoint_table_builder_(compilation_info->zone(),
  graph->tagged_stack_slots()),
  frame_translation_builder_(compilation_info->zone()),
+ source_position_table_builder_(compilation_info->zone()),
  code_gen_state_(compilation_info, &safepoint_table_builder_,
- graph->max_block_id()),
+&source_position_table_builder_, graph->max_block_id()),
  masm_(isolate->GetMainThreadIsolateUnsafe(), compilation_info->zone(),
  &code_gen_state_),
  graph_(graph),
@@ -1919,6 +1937,10 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  LocalIsolate* local_isolate) {
 if (!code_gen_succeeded_) return {};
 
+// Allocate the source position table.
+ Handle<TrustedByteArray> source_positions =
+ source_position_table_builder_.ToSourcePositionTable(local_isolate);
+
  Handle<DeoptimizationData> deopt_data =
  (v8_flags.maglev_deopt_data_on_background &&
  !v8_flags.maglev_build_code_on_background)
@@ -1934,7 +1956,7 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  .set_stack_slots(stack_slot_count_with_fixed_frame())
  .set_parameter_count(parameter_count())
  .set_deoptimization_data(deopt_data)
- .set_empty_source_position_table()
+ .set_source_position_table(source_positions)
  .set_inlined_bytecode_size(graph_->total_inlined_bytecode_size())
  .set_osr_offset(
  code_gen_state_.compilation_info()->toplevel_osr_offset());

deps/v8/src/maglev/maglev-code-generator.h

@@ -6,6 +6,7 @@
 #defineV8_MAGLEV_MAGLEV_CODE_GENERATOR_H_
 
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/deoptimizer/frame-translation-builder.h"
 #include"src/maglev/maglev-assembler.h"
@@ -54,6 +55,7 @@ class MaglevCodeGenerator final {
  LocalIsolate* local_isolate_;
  MaglevSafepointTableBuilder safepoint_table_builder_;
  FrameTranslationBuilder frame_translation_builder_;
+ SourcePositionTableBuilder source_position_table_builder_;
  MaglevCodeGenState code_gen_state_;
  MaglevAssembler masm_;
  Graph* const graph_;

deps/v8/src/maglev/maglev-compiler.cc

@@ -82,6 +82,18 @@ bool MaglevCompiler::Compile(LocalIsolate* local_isolate,
  compilation_info->set_graph_labeller(newMaglevGraphLabeller());
  }
 
+// When collecting source positions for profiling, create a graph labeller
+// so per-node provenance (including inlined positions) is recorded during
+// graph building and a real source position table can be attached to the
+// Code object.
+// Upstream V8 folds this into the single graph-labeller condition; node's
+// V8 creates the labeller in a differently-shaped block, so the condition
+// is added separately here.
+if (compilation_info->collect_source_positions() &&
+ !compilation_info->has_graph_labeller()) {
+ compilation_info->set_graph_labeller(newMaglevGraphLabeller());
+ }
+
 if (is_tracing_enabled &&
  (v8_flags.print_maglev_code || v8_flags.print_maglev_graph ||
  v8_flags.print_maglev_graphs || v8_flags.trace_maglev_graph_building ||

deps/v8/test/unittests/maglev/maglev-assembler-unittest.cc

@@ -18,7 +18,7 @@ class MaglevAssemblerTest : public MaglevTest {
 public:
 MaglevAssemblerTest()
  : MaglevTest(),
-codegen_state(nullptr, nullptr, 0),
+codegen_state(nullptr, nullptr, nullptr, 0),
  as(isolate(), zone(), &codegen_state) {}
 
 voidFinalizeAndRun(Label* pass, Label* fail) {

common.gypi

@@ -42,7 +42,7 @@
 
 # Reset this number to 0 on major V8 upgrades.
 # Increment by one for each non-official patch applied to deps/v8.
-'v8_embedder_string': '-node.52',
+'v8_embedder_string': '-node.53',
 
 ##### V8 defaults for Node.js #####
 

deps/v8/src/maglev/maglev-code-gen-state.h

@@ -9,6 +9,7 @@
 #include"src/codegen/label.h"
 #include"src/codegen/machine-type.h"
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/compiler/backend/instruction.h"
 #include"src/compiler/js-heap-broker.h"
@@ -34,9 +35,11 @@ class MaglevCodeGenState {
 public:
 MaglevCodeGenState(MaglevCompilationInfo* compilation_info,
  MaglevSafepointTableBuilder* safepoint_table_builder,
+ SourcePositionTableBuilder* source_position_table_builder,
 uint32_t max_block_id)
  : compilation_info_(compilation_info),
 safepoint_table_builder_(safepoint_table_builder),
+ source_position_table_builder_(source_position_table_builder),
  real_jump_target_(max_block_id) {}
 
 voidset_tagged_slots(int slots) { tagged_slots_ = slots; }
@@ -80,6 +83,9 @@ class MaglevCodeGenState {
  MaglevSafepointTableBuilder* safepoint_table_builder() const {
 return safepoint_table_builder_;
  }
+ SourcePositionTableBuilder* source_position_table_builder() const {
+return source_position_table_builder_;
+ }
  MaglevCompilationInfo* compilation_info() const { return compilation_info_; }
 
  Label* entry_label() { return &entry_label_; }
@@ -121,6 +127,7 @@ class MaglevCodeGenState {
 private:
  MaglevCompilationInfo* const compilation_info_;
  MaglevSafepointTableBuilder* const safepoint_table_builder_;
+ SourcePositionTableBuilder* const source_position_table_builder_;
 
  std::vector<DeferredCodeInfo*> deferred_code_;
  std::vector<EagerDeoptInfo*> eager_deopts_;

deps/v8/src/maglev/maglev-code-generator.cc

@@ -707,7 +707,14 @@ class ExceptionHandlerTrampolineBuilder {
 classMaglevCodeGeneratingNodeProcessor {
 public:
 MaglevCodeGeneratingNodeProcessor(MaglevAssembler* masm, Zone* zone)
- : masm_(masm), zone_(zone) {}
+ : masm_(masm),
+zone_(zone),
+// Cache for faster check.
+ collect_source_positions_(masm->code_gen_state()
+ ->compilation_info()
+ ->collect_source_positions()) {
+DCHECK_IMPLIES(collect_source_positions_, graph_labeller() != nullptr);
+ }
 
 voidPreProcessGraph(Graph* graph) {
 // TODO(victorgomes): I wonder if we want to create a struct that shares
@@ -800,6 +807,15 @@ class MaglevCodeGeneratingNodeProcessor {
  << PrintNode(graph_labeller(), node);
  __ RecordComment(ss.str());
  }
+if (collect_source_positions_) {
+// TODO(leszeks): Consider collecting source position in a more memory
+// friendly way, if we don't need the whole graph labeller.
+constauto& provenance = graph_labeller()->GetNodeProvenance(node);
+if (provenance.position.IsKnown()) {
+code_gen_state()->source_position_table_builder()->AddPosition(
+ masm_->pc_offset(), provenance.position, false);
+ }
+ }
 
 if (v8_flags.maglev_assert_stack_size) {
  __ AssertStackSizeCorrect();
@@ -1105,6 +1121,7 @@ class MaglevCodeGeneratingNodeProcessor {
  }
  MaglevAssembler* const masm_;
  Zone* zone_;
+bool collect_source_positions_;
 };
 
 classSafepointingNodeProcessor {
@@ -1695,8 +1712,9 @@ MaglevCodeGenerator::MaglevCodeGenerator(
  safepoint_table_builder_(compilation_info->zone(),
  graph->tagged_stack_slots()),
  frame_translation_builder_(compilation_info->zone()),
+ source_position_table_builder_(compilation_info->zone()),
  code_gen_state_(compilation_info, &safepoint_table_builder_,
- graph->max_block_id()),
+&source_position_table_builder_, graph->max_block_id()),
  masm_(isolate->GetMainThreadIsolateUnsafe(), compilation_info->zone(),
  &code_gen_state_),
  graph_(graph),
@@ -1919,6 +1937,10 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  LocalIsolate* local_isolate) {
 if (!code_gen_succeeded_) return {};
 
+// Allocate the source position table.
+ Handle<TrustedByteArray> source_positions =
+ source_position_table_builder_.ToSourcePositionTable(local_isolate);
+
  Handle<DeoptimizationData> deopt_data =
  (v8_flags.maglev_deopt_data_on_background &&
  !v8_flags.maglev_build_code_on_background)
@@ -1934,7 +1956,7 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  .set_stack_slots(stack_slot_count_with_fixed_frame())
  .set_parameter_count(parameter_count())
  .set_deoptimization_data(deopt_data)
- .set_empty_source_position_table()
+ .set_source_position_table(source_positions)
  .set_inlined_bytecode_size(graph_->total_inlined_bytecode_size())
  .set_osr_offset(
  code_gen_state_.compilation_info()->toplevel_osr_offset());

deps/v8/src/maglev/maglev-code-generator.h

@@ -6,6 +6,7 @@
 #defineV8_MAGLEV_MAGLEV_CODE_GENERATOR_H_
 
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/deoptimizer/frame-translation-builder.h"
 #include"src/maglev/maglev-assembler.h"
@@ -54,6 +55,7 @@ class MaglevCodeGenerator final {
  LocalIsolate* local_isolate_;
  MaglevSafepointTableBuilder safepoint_table_builder_;
  FrameTranslationBuilder frame_translation_builder_;
+ SourcePositionTableBuilder source_position_table_builder_;
  MaglevCodeGenState code_gen_state_;
  MaglevAssembler masm_;
  Graph* const graph_;

deps/v8/src/maglev/maglev-compiler.cc

@@ -82,6 +82,18 @@ bool MaglevCompiler::Compile(LocalIsolate* local_isolate,
  compilation_info->set_graph_labeller(newMaglevGraphLabeller());
  }
 
+// When collecting source positions for profiling, create a graph labeller
+// so per-node provenance (including inlined positions) is recorded during
+// graph building and a real source position table can be attached to the
+// Code object.
+// Upstream V8 folds this into the single graph-labeller condition; node's
+// V8 creates the labeller in a differently-shaped block, so the condition
+// is added separately here.
+if (compilation_info->collect_source_positions() &&
+ !compilation_info->has_graph_labeller()) {
+ compilation_info->set_graph_labeller(newMaglevGraphLabeller());
+ }
+
 if (is_tracing_enabled &&
  (v8_flags.print_maglev_code || v8_flags.print_maglev_graph ||
  v8_flags.print_maglev_graphs || v8_flags.trace_maglev_graph_building ||

deps/v8/test/unittests/maglev/maglev-assembler-unittest.cc

@@ -18,7 +18,7 @@ class MaglevAssemblerTest : public MaglevTest {
 public:
 MaglevAssemblerTest()
  : MaglevTest(),
-codegen_state(nullptr, nullptr, 0),
+codegen_state(nullptr, nullptr, nullptr, 0),
  as(isolate(), zone(), &codegen_state) {}
 
 voidFinalizeAndRun(Label* pass, Label* fail) {

common.gypi

@@ -42,7 +42,7 @@
 
 # Reset this number to 0 on major V8 upgrades.
 # Increment by one for each non-official patch applied to deps/v8.
-'v8_embedder_string': '-node.52',
+'v8_embedder_string': '-node.53',
 
 ##### V8 defaults for Node.js #####
 

deps/v8/src/maglev/maglev-code-gen-state.h

@@ -9,6 +9,7 @@
 #include"src/codegen/label.h"
 #include"src/codegen/machine-type.h"
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/compiler/backend/instruction.h"
 #include"src/compiler/js-heap-broker.h"
@@ -34,9 +35,11 @@ class MaglevCodeGenState {
 public:
 MaglevCodeGenState(MaglevCompilationInfo* compilation_info,
  MaglevSafepointTableBuilder* safepoint_table_builder,
+ SourcePositionTableBuilder* source_position_table_builder,
 uint32_t max_block_id)
  : compilation_info_(compilation_info),
 safepoint_table_builder_(safepoint_table_builder),
+ source_position_table_builder_(source_position_table_builder),
  real_jump_target_(max_block_id) {}
 
 voidset_tagged_slots(int slots) { tagged_slots_ = slots; }
@@ -80,6 +83,9 @@ class MaglevCodeGenState {
  MaglevSafepointTableBuilder* safepoint_table_builder() const {
 return safepoint_table_builder_;
  }
+ SourcePositionTableBuilder* source_position_table_builder() const {
+return source_position_table_builder_;
+ }
  MaglevCompilationInfo* compilation_info() const { return compilation_info_; }
 
  Label* entry_label() { return &entry_label_; }
@@ -121,6 +127,7 @@ class MaglevCodeGenState {
 private:
  MaglevCompilationInfo* const compilation_info_;
  MaglevSafepointTableBuilder* const safepoint_table_builder_;
+ SourcePositionTableBuilder* const source_position_table_builder_;
 
  std::vector<DeferredCodeInfo*> deferred_code_;
  std::vector<EagerDeoptInfo*> eager_deopts_;

deps/v8/src/maglev/maglev-code-generator.cc

@@ -707,7 +707,14 @@ class ExceptionHandlerTrampolineBuilder {
 classMaglevCodeGeneratingNodeProcessor {
 public:
 MaglevCodeGeneratingNodeProcessor(MaglevAssembler* masm, Zone* zone)
- : masm_(masm), zone_(zone) {}
+ : masm_(masm),
+zone_(zone),
+// Cache for faster check.
+ collect_source_positions_(masm->code_gen_state()
+ ->compilation_info()
+ ->collect_source_positions()) {
+DCHECK_IMPLIES(collect_source_positions_, graph_labeller() != nullptr);
+ }
 
 voidPreProcessGraph(Graph* graph) {
 // TODO(victorgomes): I wonder if we want to create a struct that shares
@@ -800,6 +807,15 @@ class MaglevCodeGeneratingNodeProcessor {
  << PrintNode(graph_labeller(), node);
  __ RecordComment(ss.str());
  }
+if (collect_source_positions_) {
+// TODO(leszeks): Consider collecting source position in a more memory
+// friendly way, if we don't need the whole graph labeller.
+constauto& provenance = graph_labeller()->GetNodeProvenance(node);
+if (provenance.position.IsKnown()) {
+code_gen_state()->source_position_table_builder()->AddPosition(
+ masm_->pc_offset(), provenance.position, false);
+ }
+ }
 
 if (v8_flags.maglev_assert_stack_size) {
  __ AssertStackSizeCorrect();
@@ -1105,6 +1121,7 @@ class MaglevCodeGeneratingNodeProcessor {
  }
  MaglevAssembler* const masm_;
  Zone* zone_;
+bool collect_source_positions_;
 };
 
 classSafepointingNodeProcessor {
@@ -1695,8 +1712,9 @@ MaglevCodeGenerator::MaglevCodeGenerator(
  safepoint_table_builder_(compilation_info->zone(),
  graph->tagged_stack_slots()),
  frame_translation_builder_(compilation_info->zone()),
+ source_position_table_builder_(compilation_info->zone()),
  code_gen_state_(compilation_info, &safepoint_table_builder_,
- graph->max_block_id()),
+&source_position_table_builder_, graph->max_block_id()),
  masm_(isolate->GetMainThreadIsolateUnsafe(), compilation_info->zone(),
  &code_gen_state_),
  graph_(graph),
@@ -1919,6 +1937,10 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  LocalIsolate* local_isolate) {
 if (!code_gen_succeeded_) return {};
 
+// Allocate the source position table.
+ Handle<TrustedByteArray> source_positions =
+ source_position_table_builder_.ToSourcePositionTable(local_isolate);
+
  Handle<DeoptimizationData> deopt_data =
  (v8_flags.maglev_deopt_data_on_background &&
  !v8_flags.maglev_build_code_on_background)
@@ -1934,7 +1956,7 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  .set_stack_slots(stack_slot_count_with_fixed_frame())
  .set_parameter_count(parameter_count())
  .set_deoptimization_data(deopt_data)
- .set_empty_source_position_table()
+ .set_source_position_table(source_positions)
  .set_inlined_bytecode_size(graph_->total_inlined_bytecode_size())
  .set_osr_offset(
  code_gen_state_.compilation_info()->toplevel_osr_offset());

deps/v8/src/maglev/maglev-code-generator.h

@@ -6,6 +6,7 @@
 #defineV8_MAGLEV_MAGLEV_CODE_GENERATOR_H_
 
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/deoptimizer/frame-translation-builder.h"
 #include"src/maglev/maglev-assembler.h"
@@ -54,6 +55,7 @@ class MaglevCodeGenerator final {
  LocalIsolate* local_isolate_;
  MaglevSafepointTableBuilder safepoint_table_builder_;
  FrameTranslationBuilder frame_translation_builder_;
+ SourcePositionTableBuilder source_position_table_builder_;
  MaglevCodeGenState code_gen_state_;
  MaglevAssembler masm_;
  Graph* const graph_;

deps/v8/src/maglev/maglev-compiler.cc

@@ -82,6 +82,18 @@ bool MaglevCompiler::Compile(LocalIsolate* local_isolate,
  compilation_info->set_graph_labeller(newMaglevGraphLabeller());
  }
 
+// When collecting source positions for profiling, create a graph labeller
+// so per-node provenance (including inlined positions) is recorded during
+// graph building and a real source position table can be attached to the
+// Code object.
+// Upstream V8 folds this into the single graph-labeller condition; node's
+// V8 creates the labeller in a differently-shaped block, so the condition
+// is added separately here.
+if (compilation_info->collect_source_positions() &&
+ !compilation_info->has_graph_labeller()) {
+ compilation_info->set_graph_labeller(newMaglevGraphLabeller());
+ }
+
 if (is_tracing_enabled &&
  (v8_flags.print_maglev_code || v8_flags.print_maglev_graph ||
  v8_flags.print_maglev_graphs || v8_flags.trace_maglev_graph_building ||

deps/v8/test/unittests/maglev/maglev-assembler-unittest.cc

@@ -18,7 +18,7 @@ class MaglevAssemblerTest : public MaglevTest {
 public:
 MaglevAssemblerTest()
  : MaglevTest(),
-codegen_state(nullptr, nullptr, 0),
+codegen_state(nullptr, nullptr, nullptr, 0),
  as(isolate(), zone(), &codegen_state) {}
 
 voidFinalizeAndRun(Label* pass, Label* fail) {

common.gypi

@@ -42,7 +42,7 @@
 
 # Reset this number to 0 on major V8 upgrades.
 # Increment by one for each non-official patch applied to deps/v8.
-'v8_embedder_string': '-node.52',
+'v8_embedder_string': '-node.53',
 
 ##### V8 defaults for Node.js #####
 

deps/v8/src/maglev/maglev-code-gen-state.h

@@ -9,6 +9,7 @@
 #include"src/codegen/label.h"
 #include"src/codegen/machine-type.h"
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/compiler/backend/instruction.h"
 #include"src/compiler/js-heap-broker.h"
@@ -34,9 +35,11 @@ class MaglevCodeGenState {
 public:
 MaglevCodeGenState(MaglevCompilationInfo* compilation_info,
  MaglevSafepointTableBuilder* safepoint_table_builder,
+ SourcePositionTableBuilder* source_position_table_builder,
 uint32_t max_block_id)
  : compilation_info_(compilation_info),
 safepoint_table_builder_(safepoint_table_builder),
+ source_position_table_builder_(source_position_table_builder),
  real_jump_target_(max_block_id) {}
 
 voidset_tagged_slots(int slots) { tagged_slots_ = slots; }
@@ -80,6 +83,9 @@ class MaglevCodeGenState {
  MaglevSafepointTableBuilder* safepoint_table_builder() const {
 return safepoint_table_builder_;
  }
+ SourcePositionTableBuilder* source_position_table_builder() const {
+return source_position_table_builder_;
+ }
  MaglevCompilationInfo* compilation_info() const { return compilation_info_; }
 
  Label* entry_label() { return &entry_label_; }
@@ -121,6 +127,7 @@ class MaglevCodeGenState {
 private:
  MaglevCompilationInfo* const compilation_info_;
  MaglevSafepointTableBuilder* const safepoint_table_builder_;
+ SourcePositionTableBuilder* const source_position_table_builder_;
 
  std::vector<DeferredCodeInfo*> deferred_code_;
  std::vector<EagerDeoptInfo*> eager_deopts_;

deps/v8/src/maglev/maglev-code-generator.cc

@@ -707,7 +707,14 @@ class ExceptionHandlerTrampolineBuilder {
 classMaglevCodeGeneratingNodeProcessor {
 public:
 MaglevCodeGeneratingNodeProcessor(MaglevAssembler* masm, Zone* zone)
- : masm_(masm), zone_(zone) {}
+ : masm_(masm),
+zone_(zone),
+// Cache for faster check.
+ collect_source_positions_(masm->code_gen_state()
+ ->compilation_info()
+ ->collect_source_positions()) {
+DCHECK_IMPLIES(collect_source_positions_, graph_labeller() != nullptr);
+ }
 
 voidPreProcessGraph(Graph* graph) {
 // TODO(victorgomes): I wonder if we want to create a struct that shares
@@ -800,6 +807,15 @@ class MaglevCodeGeneratingNodeProcessor {
  << PrintNode(graph_labeller(), node);
  __ RecordComment(ss.str());
  }
+if (collect_source_positions_) {
+// TODO(leszeks): Consider collecting source position in a more memory
+// friendly way, if we don't need the whole graph labeller.
+constauto& provenance = graph_labeller()->GetNodeProvenance(node);
+if (provenance.position.IsKnown()) {
+code_gen_state()->source_position_table_builder()->AddPosition(
+ masm_->pc_offset(), provenance.position, false);
+ }
+ }
 
 if (v8_flags.maglev_assert_stack_size) {
  __ AssertStackSizeCorrect();
@@ -1105,6 +1121,7 @@ class MaglevCodeGeneratingNodeProcessor {
  }
  MaglevAssembler* const masm_;
  Zone* zone_;
+bool collect_source_positions_;
 };
 
 classSafepointingNodeProcessor {
@@ -1695,8 +1712,9 @@ MaglevCodeGenerator::MaglevCodeGenerator(
  safepoint_table_builder_(compilation_info->zone(),
  graph->tagged_stack_slots()),
  frame_translation_builder_(compilation_info->zone()),
+ source_position_table_builder_(compilation_info->zone()),
  code_gen_state_(compilation_info, &safepoint_table_builder_,
- graph->max_block_id()),
+&source_position_table_builder_, graph->max_block_id()),
  masm_(isolate->GetMainThreadIsolateUnsafe(), compilation_info->zone(),
  &code_gen_state_),
  graph_(graph),
@@ -1919,6 +1937,10 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  LocalIsolate* local_isolate) {
 if (!code_gen_succeeded_) return {};
 
+// Allocate the source position table.
+ Handle<TrustedByteArray> source_positions =
+ source_position_table_builder_.ToSourcePositionTable(local_isolate);
+
  Handle<DeoptimizationData> deopt_data =
  (v8_flags.maglev_deopt_data_on_background &&
  !v8_flags.maglev_build_code_on_background)
@@ -1934,7 +1956,7 @@ MaybeHandle<Code> MaglevCodeGenerator::BuildCodeObject(
  .set_stack_slots(stack_slot_count_with_fixed_frame())
  .set_parameter_count(parameter_count())
  .set_deoptimization_data(deopt_data)
- .set_empty_source_position_table()
+ .set_source_position_table(source_positions)
  .set_inlined_bytecode_size(graph_->total_inlined_bytecode_size())
  .set_osr_offset(
  code_gen_state_.compilation_info()->toplevel_osr_offset());

deps/v8/src/maglev/maglev-code-generator.h

@@ -6,6 +6,7 @@
 #defineV8_MAGLEV_MAGLEV_CODE_GENERATOR_H_
 
 #include"src/codegen/maglev-safepoint-table.h"
+#include"src/codegen/source-position-table.h"
 #include"src/common/globals.h"
 #include"src/deoptimizer/frame-translation-builder.h"
 #include"src/maglev/maglev-assembler.h"
@@ -54,6 +55,7 @@ class MaglevCodeGenerator final {
  LocalIsolate* local_isolate_;
  MaglevSafepointTableBuilder safepoint_table_builder_;
  FrameTranslationBuilder frame_translation_builder_;
+ SourcePositionTableBuilder source_position_table_builder_;
  MaglevCodeGenState code_gen_state_;
  MaglevAssembler masm_;
  Graph* const graph_;

deps/v8/src/maglev/maglev-compiler.cc

@@ -82,6 +82,18 @@ bool MaglevCompiler::Compile(LocalIsolate* local_isolate,
  compilation_info->set_graph_labeller(newMaglevGraphLabeller());
  }
 
+// When collecting source positions for profiling, create a graph labeller
+// so per-node provenance (including inlined positions) is recorded during
+// graph building and a real source position table can be attached to the
+// Code object.
+// Upstream V8 folds this into the single graph-labeller condition; node's
+// V8 creates the labeller in a differently-shaped block, so the condition
+// is added separately here.
+if (compilation_info->collect_source_positions() &&
+ !compilation_info->has_graph_labeller()) {
+ compilation_info->set_graph_labeller(newMaglevGraphLabeller());
+ }
+
 if (is_tracing_enabled &&
  (v8_flags.print_maglev_code || v8_flags.print_maglev_graph ||
  v8_flags.print_maglev_graphs || v8_flags.trace_maglev_graph_building ||

deps/v8/test/unittests/maglev/maglev-assembler-unittest.cc

@@ -18,7 +18,7 @@ class MaglevAssemblerTest : public MaglevTest {
 public:
 MaglevAssemblerTest()
  : MaglevTest(),
-codegen_state(nullptr, nullptr, 0),
+codegen_state(nullptr, nullptr, nullptr, 0),
  as(isolate(), zone(), &codegen_state) {}
 
 voidFinalizeAndRun(Label* pass, Label* fail) {