commit 09d041b214f54e0866516b18b44e44f28d7be70b
author Vladimir Marko <vmarko@google.com> Mon Jul 30 12:51:59 2018 +0100
committer Vladimir Marko <vmarko@google.com> Thu Aug 16 16:13:44 2018 +0100
tree 607da2425d2a6d7920ad344f5a16126c0d3c49ce
parent d7a0192ffa9c9015f0980b1aaa694e914a37d57f

Reduce memory usage by other deps in scheduler.

Rely on transitive dependencies instead of adding the full
set of side effect dependencies.

Compiling a certain apk, the most memory hungry method has
the scheduler memory allocations in ArenaStack hidden by
the register allocator:
  - before:
    MEM: used: 155744672, allocated: 168446408, lost: 12036488
    Scheduler     155744672
  - after:
    MEM: used: 5181680, allocated: 7096776, lost: 114752
    SsaLiveness     4683440
    RegAllocator     314312
    RegAllocVldt     183928
The total arena memory used, including the ArenaAllocator
not listed above, goes from 167170024 to 16607032 (-90%).
(Measured with kArenaAllocatorCountAllocations=true,
kArenaAllocatorPreciseTracking=false.)

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 64312607
Change-Id: I825bcfb490171070c46ad6d1f460785f4e75cfd7

compiler/optimizing/scheduler_test.cc

diff --git a/compiler/optimizing/scheduler_test.cc b/compiler/optimizing/scheduler_test.cc
index fe23fb4..981fcc4 100644
--- a/compiler/optimizing/scheduler_test.cc
+++ b/compiler/optimizing/scheduler_test.cc
@@ -171,7 +171,9 @@
     ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(array_set1, array_get1));
     ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(array_set2, array_get2));
     ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(array_get2, array_set1));
-    ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(array_set2, array_set1));
+    // Unnecessary dependency is not stored, we rely on transitive dependencies.
+    // The array_set2 -> array_get2 -> array_set1 dependencies are tested above.
+    ASSERT_FALSE(scheduling_graph.HasImmediateOtherDependency(array_set2, array_set1));
 
     // Env dependency.
     ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(div_check, mul));
@@ -308,7 +310,9 @@
     loc1 = heap_location_collector.GetArrayHeapLocation(arr_set_i);
     loc2 = heap_location_collector.GetArrayHeapLocation(arr_set_j);
     ASSERT_TRUE(heap_location_collector.MayAlias(loc1, loc2));
-    ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_i));
+    // Unnecessary dependency is not stored, we rely on transitive dependencies.
+    // The arr_set_j -> arr_set_sub0 -> arr_set_add0 -> arr_set_i dependencies are tested below.
+    ASSERT_FALSE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_i));
 
     // Test side effect dependency based on LSA analysis: array[i] and array[i+0]
     loc1 = heap_location_collector.GetArrayHeapLocation(arr_set_i);
@@ -320,7 +324,10 @@
     loc1 = heap_location_collector.GetArrayHeapLocation(arr_set_i);
     loc2 = heap_location_collector.GetArrayHeapLocation(arr_set_sub0);
     ASSERT_TRUE(heap_location_collector.MayAlias(loc1, loc2));
-    ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(arr_set_sub0, arr_set_i));
+    // Unnecessary dependency is not stored, we rely on transitive dependencies.
+    ASSERT_FALSE(scheduling_graph.HasImmediateOtherDependency(arr_set_sub0, arr_set_i));
+    // Instead, we rely on arr_set_sub0 -> arr_set_add0 -> arr_set_i, the latter is tested above.
+    ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(arr_set_sub0, arr_set_add0));
 
     // Test side effect dependency based on LSA analysis: array[i] and array[i+1]
     loc1 = heap_location_collector.GetArrayHeapLocation(arr_set_i);
@@ -335,11 +342,12 @@
     ASSERT_FALSE(scheduling_graph.HasImmediateOtherDependency(arr_set_sub1, arr_set_add1));
 
     // Test side effect dependency based on LSA analysis: array[j] and all others array accesses
-    ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_i));
-    ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_add0));
     ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_sub0));
     ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_add1));
     ASSERT_TRUE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_sub1));
+    // Unnecessary dependencies are not stored, we rely on transitive dependencies.
+    ASSERT_FALSE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_i));
+    ASSERT_FALSE(scheduling_graph.HasImmediateOtherDependency(arr_set_j, arr_set_add0));
 
     // Test that ArraySet and FieldSet should not have side effect dependency
     ASSERT_FALSE(scheduling_graph.HasImmediateOtherDependency(arr_set_i, set_field10));