Revert of [heap] Decouple old generation allocation limit from external...

Revert of [heap] Decouple old generation allocation limit from external memory. (patchset #1 id:1 of https://codereview.chromium.org/2329993002/ )

Reason for revert:
Regressions in telemetry benchmarks:
crbug.com/646819.

Original issue's description:
> [heap] Decouple old generation allocation limit from external memory.
>
> We check for external memory limit in Heap::ReportExternalMemoryPressure.
>
> BUG=chromium:616434
>
> Committed: https://crrev.com/672d079ccba686019fa1457c83b42c2e692ef88b
> Cr-Commit-Position: refs/heads/master@{#39374}

TBR=hpayer@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:616434

Review-Url: https://codereview.chromium.org/2339033005
Cr-Commit-Position: refs/heads/master@{#39442}

src/heap/heap-inl.h

@@ -192,7 +192,7 @@ bool Heap::HeapIsFullEnoughToStartIncrementalMarking(intptr_t limit) {
 
   intptr_t adjusted_allocation_limit = limit - new_space_->Capacity();
 
-  if (PromotedSpaceSizeOfObjects() >= adjusted_allocation_limit) return true;
+  if (PromotedTotalSize() >= adjusted_allocation_limit) return true;
 
   if (HighMemoryPressure()) return true;
 

src/heap/heap.h

@@ -1353,6 +1353,16 @@ class Heap {
     survived_since_last_expansion_ += survived;
   }
 
+  inline intptr_t PromotedTotalSize() {
+    int64_t total = PromotedSpaceSizeOfObjects() + PromotedExternalMemorySize();
+    if (total > std::numeric_limits<intptr_t>::max()) {
+      // TODO(erikcorry): Use uintptr_t everywhere we do heap size calculations.
+      return std::numeric_limits<intptr_t>::max();
+    }
+    if (total < 0) return 0;
+    return static_cast<intptr_t>(total);
+  }
+
   inline void UpdateNewSpaceAllocationCounter();
 
   inline size_t NewSpaceAllocationCounter();
@@ -1795,7 +1805,7 @@ class Heap {
   // ===========================================================================
 
   inline intptr_t OldGenerationSpaceAvailable() {
-    return old_generation_allocation_limit_ - PromotedSpaceSizeOfObjects();
+    return old_generation_allocation_limit_ - PromotedTotalSize();
   }
 
   // Returns maximum GC pause.

src/heap/incremental-marking.cc

@@ -1112,7 +1112,7 @@ void IncrementalMarking::SpeedUp() {
   }
 
   bool size_of_old_space_multiplied_by_n_during_marking =
-      (heap_->PromotedSpaceSizeOfObjects() >
+      (heap_->PromotedTotalSize() >
        (marking_speed_ + 1) *
            old_generation_space_used_at_start_of_incremental_);
   if (size_of_old_space_multiplied_by_n_during_marking) {
@@ -1125,7 +1125,7 @@ void IncrementalMarking::SpeedUp() {
   }
 
   int64_t promoted_during_marking =
-      heap_->PromotedSpaceSizeOfObjects() -
+      heap_->PromotedTotalSize() -
       old_generation_space_used_at_start_of_incremental_;
   intptr_t delay = marking_speed_ * MB;
   intptr_t scavenge_slack = heap_->MaxSemiSpaceSize();
@@ -1300,7 +1300,7 @@ void IncrementalMarking::ResetStepCounters() {
   old_generation_space_available_at_start_of_incremental_ =
       SpaceLeftInOldSpace();
   old_generation_space_used_at_start_of_incremental_ =
-      heap_->PromotedSpaceSizeOfObjects();
+      heap_->PromotedTotalSize();
   bytes_rescanned_ = 0;
   marking_speed_ = kInitialMarkingSpeed;
   bytes_scanned_ = 0;