[turbofan] Remove escape analysis stats counters.

These counters were used during the initial implementation to gather
statistics about comparative effectiveness of the two escape analysis
approaches in practice. The counters are not thread-safe and cannot be
used for the analysis any longer as it is now running off main thread.
We deprecate the counters in question in favor of maintaining deferred
statistics until the need for such statistics arises again.

R=bmeurer@chromium.org
BUG=chromium:685942

Review-Url: https://codereview.chromium.org/2667453003
Cr-Commit-Position: refs/heads/master@{#42808}

src/compiler/escape-analysis-reducer.cc

@@ -139,7 +139,6 @@ Reduction EscapeAnalysisReducer::ReduceLoad(Node* node) {
   if (escape_analysis()->IsVirtual(
           SkipTypeGuards(NodeProperties::GetValueInput(node, 0)))) {
     if (Node* rep = escape_analysis()->GetReplacement(node)) {
-      isolate()->counters()->turbo_escape_loads_replaced()->Increment();
       TRACE("Replaced #%d (%s) with #%d (%s)\n", node->id(),
             node->op()->mnemonic(), rep->id(), rep->op()->mnemonic());
       rep = MaybeGuard(jsgraph(), zone(), node, rep);
@@ -175,7 +174,6 @@ Reduction EscapeAnalysisReducer::ReduceAllocate(Node* node) {
   }
   if (escape_analysis()->IsVirtual(node)) {
     RelaxEffectsAndControls(node);
-    isolate()->counters()->turbo_escape_allocs_replaced()->Increment();
     TRACE("Removed allocate #%d from effect chain\n", node->id());
     return Changed(node);
   }
@@ -382,8 +380,6 @@ void EscapeAnalysisReducer::VerifyReplacement() const {
 #endif  // DEBUG
 }
 
-Isolate* EscapeAnalysisReducer::isolate() const { return jsgraph_->isolate(); }
-
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8

src/compiler/escape-analysis-reducer.h

@@ -49,7 +49,6 @@ class V8_EXPORT_PRIVATE EscapeAnalysisReducer final
   JSGraph* jsgraph() const { return jsgraph_; }
   EscapeAnalysis* escape_analysis() const { return escape_analysis_; }
   Zone* zone() const { return zone_; }
-  Isolate* isolate() const;
 
   JSGraph* const jsgraph_;
   EscapeAnalysis* escape_analysis_;

src/counters.h

@@ -1148,10 +1148,6 @@ class RuntimeCallTimerScope {
   SC(lo_space_bytes_available, V8.MemoryLoSpaceBytesAvailable)                 \
   SC(lo_space_bytes_committed, V8.MemoryLoSpaceBytesCommitted)                 \
   SC(lo_space_bytes_used, V8.MemoryLoSpaceBytesUsed)                           \
-  SC(turbo_escape_allocs_replaced, V8.TurboEscapeAllocsReplaced)               \
-  SC(crankshaft_escape_allocs_replaced, V8.CrankshaftEscapeAllocsReplaced)     \
-  SC(turbo_escape_loads_replaced, V8.TurboEscapeLoadsReplaced)                 \
-  SC(crankshaft_escape_loads_replaced, V8.CrankshaftEscapeLoadsReplaced)       \
   /* Total code size (including metadata) of baseline code or bytecode. */     \
   SC(total_baseline_code_size, V8.TotalBaselineCodeSize)                       \
   /* Total count of functions compiled using the baseline compiler. */         \

src/crankshaft/hydrogen-escape-analysis.cc

@@ -142,7 +142,6 @@ HValue* HEscapeAnalysisPhase::NewMapCheckAndInsert(HCapturedObject* state,
 // necessary.
 HValue* HEscapeAnalysisPhase::NewLoadReplacement(
     HLoadNamedField* load, HValue* load_value) {
-  isolate()->counters()->crankshaft_escape_loads_replaced()->Increment();
   HValue* replacement = load_value;
   Representation representation = load->representation();
   if (representation.IsSmiOrInteger32() || representation.IsDouble()) {
@@ -320,8 +319,6 @@ void HEscapeAnalysisPhase::Run() {
   for (int i = 0; i < max_fixpoint_iteration_count; i++) {
     CollectCapturedValues();
     if (captured_.is_empty()) break;
-    isolate()->counters()->crankshaft_escape_allocs_replaced()->Increment(
-        captured_.length());
     PerformScalarReplacement();
     captured_.Rewind(0);
   }