[heap] make inline allocation step size dynamic

src/heap/spaces.cc

Index: src/heap/spaces.cc
diff --git a/src/heap/spaces.cc b/src/heap/spaces.cc
index a5e2760bb09d0004cfc8dec007121f946fda583c..3cfd4c4e75815033e5be277626a3f1f01c43ea1c 100644
--- a/src/heap/spaces.cc
+++ b/src/heap/spaces.cc
@@ -1516,7 +1516,15 @@ void NewSpace::UpdateInlineAllocationLimit(int size_in_bytes) {
     // Lower limit during incremental marking.
     Address high = to_space_.page_high();
     Address new_top = allocation_info_.top() + size_in_bytes;
-    Address new_limit = new_top + inline_allocation_limit_step_;
+
+    intptr_t next_step = 0;
+    for (int i = 0; i < inline_allocation_observers_.length(); ++i) {

[Hannes Payer (out of office), 2015/11/09 19:26:39]

Can we move that code into a helper function?

[ofrobots, 2015/11/09 23:00:32]

Done.

+      InlineAllocationObserver* o = inline_allocation_observers_[i];
+      next_step = next_step ? Min(next_step, o->bytes_to_next_step())
+                            : o->bytes_to_next_step();
+    }
+    DCHECK(next_step != 0);
+    Address new_limit = new_top + next_step;
     allocation_info_.set_limit(Min(new_limit, high));
   }
   DCHECK_SEMISPACE_ALLOCATION_INFO(allocation_info_, to_space_);
@@ -1602,13 +1610,8 @@ bool NewSpace::EnsureAllocation(int size_in_bytes,
 
 
 void NewSpace::UpdateInlineAllocationLimitStep() {
-  intptr_t step = 0;
-  for (int i = 0; i < inline_allocation_observers_.length(); ++i) {
-    InlineAllocationObserver* observer = inline_allocation_observers_[i];
-    step = step ? Min(step, observer->step_size()) : observer->step_size();
-  }
-  inline_allocation_limit_step_ = step;
-  top_on_previous_step_ = step ? allocation_info_.top() : 0;
+  top_on_previous_step_ =

[Hannes Payer (out of office), 2015/11/09 19:26:39]

This method is now just updating top_on_previous_step_. We should rename this
method to reflect that.

[ofrobots, 2015/11/09 23:00:32]

Done.

+      inline_allocation_observers_.length() ? allocation_info_.top() : 0;
   UpdateInlineAllocationLimit(0);
 }