Rename size_pool -> heap

Now that we've inlined the eden_heap into the size_pool, we should
rename the size_pool to heap. So that Ruby contains multiple heaps, with
different sized objects.

The term heap as a collection of memory pages is more in memory
management nomenclature, whereas size_pool was a name chosen out of
necessity during the development of the Variable Width Allocation
features of Ruby.

The concept of size pools was introduced in order to facilitate
different sized objects (other than the default 40 bytes). They wrapped
the eden heap and the tomb heap, and some related state, and provided a
reasonably simple way of duplicating all related concerns, to provide
multiple pools that all shared the same structure but held different
objects.

Since then various changes have happend in Ruby's memory layout:

* The concept of tomb heaps has been replaced by a global free pages list,
  with each page having it's slot size reconfigured at the point when it
  is resurrected
* the eden heap has been inlined into the size pool itself, so that now
  the size pool directly controls the free_pages list, the sweeping
  page, the compaction cursor and the other state that was previously
  being managed by the eden heap.

Now that there is no need for a heap wrapper, we should refer to the
collection of pages containing Ruby objects as a heap again rather than
a size pool

3 files changed, 14 insertions, 14 deletions

diff --git a/test/ruby/test_gc.rb b/test/ruby/test_gc.rb
index 9a9796dc55..31ad71a1a1 100644
--- a/test/ruby/test_gc.rb
+++ b/test/ruby/test_gc.rb
@@ -226,7 +226,7 @@ class TestGc < Test::Unit::TestCase
     GC.stat_heap(0, stat_heap)
     GC.stat(stat)
 
-    GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT].times do |i|
+    GC::INTERNAL_CONSTANTS[:HEAP_COUNT].times do |i|
       EnvUtil.without_gc do
         GC.stat_heap(i, stat_heap)
         GC.stat(stat)
@@ -248,7 +248,7 @@ class TestGc < Test::Unit::TestCase
     assert_equal stat_heap[:slot_size], GC.stat_heap(0)[:slot_size]
 
     assert_raise(ArgumentError) { GC.stat_heap(-1) }
-    assert_raise(ArgumentError) { GC.stat_heap(GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT]) }
+    assert_raise(ArgumentError) { GC.stat_heap(GC::INTERNAL_CONSTANTS[:HEAP_COUNT]) }
   end
 
   def test_stat_heap_all
@@ -259,7 +259,7 @@ class TestGc < Test::Unit::TestCase
     GC.stat_heap(0, stat_heap)
     GC.stat_heap(nil, stat_heap_all)
 
-    GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT].times do |i|
+    GC::INTERNAL_CONSTANTS[:HEAP_COUNT].times do |i|
       GC.stat_heap(nil, stat_heap_all)
       GC.stat_heap(i, stat_heap)
 
@@ -538,7 +538,7 @@ class TestGc < Test::Unit::TestCase
 
       gc_count = GC.stat(:count)
       # Fill up all of the size pools to the init slots
-      GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT].times do |i|
+      GC::INTERNAL_CONSTANTS[:HEAP_COUNT].times do |i|
         capa = (GC.stat_heap(i, :slot_size) - GC::INTERNAL_CONSTANTS[:RVALUE_OVERHEAD] - (2 * RbConfig::SIZEOF["void*"])) / RbConfig::SIZEOF["void*"]
         while GC.stat_heap(i, :heap_eden_slots) < GC_HEAP_INIT_SLOTS
           Array.new(capa)
@@ -558,7 +558,7 @@ class TestGc < Test::Unit::TestCase
 
       gc_count = GC.stat(:count)
       # Fill up all of the size pools to the init slots
-      GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT].times do |i|
+      GC::INTERNAL_CONSTANTS[:HEAP_COUNT].times do |i|
         capa = (GC.stat_heap(i, :slot_size) - GC::INTERNAL_CONSTANTS[:RVALUE_OVERHEAD] - (2 * RbConfig::SIZEOF["void*"])) / RbConfig::SIZEOF["void*"]
         while GC.stat_heap(i, :heap_eden_slots) < SIZES[i]
           Array.new(capa)
diff --git a/test/ruby/test_gc_compact.rb b/test/ruby/test_gc_compact.rb
index c331968b3d..26d7c71687 100644
--- a/test/ruby/test_gc_compact.rb
+++ b/test/ruby/test_gc_compact.rb
@@ -283,7 +283,7 @@ class TestGCCompact < Test::Unit::TestCase
     end;
   end
 
-  def test_moving_arrays_down_size_pools
+  def test_moving_arrays_down_heaps
     omit if GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT] == 1
 
     assert_separately(%w[-robjspace], "#{<<~"begin;"}\n#{<<~"end;"}", timeout: 10)
@@ -305,7 +305,7 @@ class TestGCCompact < Test::Unit::TestCase
     end;
   end
 
-  def test_moving_arrays_up_size_pools
+  def test_moving_arrays_up_heaps
     omit if GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT] == 1
 
     assert_separately(%w[-robjspace], "#{<<~"begin;"}\n#{<<~"end;"}", timeout: 10)
@@ -329,7 +329,7 @@ class TestGCCompact < Test::Unit::TestCase
     end;
   end
 
-  def test_moving_objects_between_size_pools
+  def test_moving_objects_between_heaps
     omit if GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT] == 1
 
     assert_separately(%w[-robjspace], "#{<<~"begin;"}\n#{<<~"end;"}", timeout: 60)
@@ -361,7 +361,7 @@ class TestGCCompact < Test::Unit::TestCase
     end;
   end
 
-  def test_moving_strings_up_size_pools
+  def test_moving_strings_up_heaps
     omit if GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT] == 1
 
     assert_separately(%w[-robjspace], "#{<<~"begin;"}\n#{<<~"end;"}", timeout: 30)
@@ -382,7 +382,7 @@ class TestGCCompact < Test::Unit::TestCase
     end;
   end
 
-  def test_moving_strings_down_size_pools
+  def test_moving_strings_down_heaps
     omit if GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT] == 1
 
     assert_separately(%w[-robjspace], "#{<<~"begin;"}\n#{<<~"end;"}", timeout: 30)
@@ -402,7 +402,7 @@ class TestGCCompact < Test::Unit::TestCase
     end;
   end
 
-  def test_moving_hashes_down_size_pools
+  def test_moving_hashes_down_heaps
     omit if GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT] == 1
     # AR and ST hashes are in the same size pool on 32 bit
     omit unless RbConfig::SIZEOF["uint64_t"] <= RbConfig::SIZEOF["void*"]
@@ -425,7 +425,7 @@ class TestGCCompact < Test::Unit::TestCase
     end;
   end
 
-  def test_moving_objects_between_size_pools_keeps_shape_frozen_status
+  def test_moving_objects_between_heaps_keeps_shape_frozen_status
     # [Bug #19536]
     assert_separately([], "#{<<~"begin;"}\n#{<<~"end;"}")
     begin;
diff --git a/test/ruby/test_string.rb b/test/ruby/test_string.rb
index 8658097ae4..ba8d86d442 100644
--- a/test/ruby/test_string.rb
+++ b/test/ruby/test_string.rb
@@ -662,8 +662,8 @@ CODE
     assert_equal(Encoding::UTF_8, "#{s}x".encoding)
   end
 
-  def test_string_interpolations_across_size_pools_get_embedded
-    omit if GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT] == 1
+  def test_string_interpolations_across_heaps_get_embedded
+    omit if GC::INTERNAL_CONSTANTS[:HEAP_COUNT] == 1
 
     require 'objspace'
     base_slot_size = GC::INTERNAL_CONSTANTS[:BASE_SLOT_SIZE]