GVN final fields even with side effects.
Two accesses of a final field can be GVN'ed even if there are
side effects between them.
Change-Id: I04495ae83c7858f4216b083ad1c29851954320ad
diff --git a/compiler/optimizing/builder.cc b/compiler/optimizing/builder.cc
index 0f44af0..c04fe4e 100644
--- a/compiler/optimizing/builder.cc
+++ b/compiler/optimizing/builder.cc
@@ -816,6 +816,7 @@
current_block_->GetLastInstruction(),
field_type,
resolved_field->GetOffset(),
+ resolved_field->IsFinal(),
resolved_field->IsVolatile()));
UpdateLocal(source_or_dest_reg, current_block_->GetLastInstruction());
@@ -917,13 +918,19 @@
temps.Add(cls);
HInstruction* value = LoadLocal(source_or_dest_reg, field_type);
DCHECK_EQ(value->GetType(), field_type);
- current_block_->AddInstruction(
- new (arena_) HStaticFieldSet(cls, value, field_type, resolved_field->GetOffset(),
- resolved_field->IsVolatile()));
+ current_block_->AddInstruction(new (arena_) HStaticFieldSet(
+ cls,
+ value,
+ field_type,
+ resolved_field->GetOffset(),
+ resolved_field->IsVolatile()));
} else {
- current_block_->AddInstruction(
- new (arena_) HStaticFieldGet(cls, field_type, resolved_field->GetOffset(),
- resolved_field->IsVolatile()));
+ current_block_->AddInstruction(new (arena_) HStaticFieldGet(
+ cls,
+ field_type,
+ resolved_field->GetOffset(),
+ resolved_field->IsFinal(),
+ resolved_field->IsVolatile()));
UpdateLocal(source_or_dest_reg, current_block_->GetLastInstruction());
}
return true;
diff --git a/compiler/optimizing/gvn_test.cc b/compiler/optimizing/gvn_test.cc
index a81d49a..59854d7 100644
--- a/compiler/optimizing/gvn_test.cc
+++ b/compiler/optimizing/gvn_test.cc
@@ -42,21 +42,21 @@
block->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimNot,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
block->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimNot,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
HInstruction* to_remove = block->GetLastInstruction();
block->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimNot,
- MemberOffset(43), false));
+ MemberOffset(43), false, false));
HInstruction* different_offset = block->GetLastInstruction();
// Kill the value.
block->AddInstruction(new (&allocator) HInstanceFieldSet(
parameter, parameter, Primitive::kPrimNot, MemberOffset(42), false));
block->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimNot,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
HInstruction* use_after_kill = block->GetLastInstruction();
block->AddInstruction(new (&allocator) HExit());
@@ -90,7 +90,7 @@
entry->AddSuccessor(block);
block->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimBoolean,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
block->AddInstruction(new (&allocator) HIf(block->GetLastInstruction()));
HBasicBlock* then = new (&allocator) HBasicBlock(graph);
@@ -107,15 +107,15 @@
then->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimBoolean,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
then->AddInstruction(new (&allocator) HGoto());
else_->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimBoolean,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
else_->AddInstruction(new (&allocator) HGoto());
join->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimBoolean,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
join->AddInstruction(new (&allocator) HExit());
graph->TryBuildingSsa();
@@ -146,7 +146,7 @@
entry->AddSuccessor(block);
block->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimBoolean,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
block->AddInstruction(new (&allocator) HGoto());
HBasicBlock* loop_header = new (&allocator) HBasicBlock(graph);
@@ -163,7 +163,7 @@
loop_header->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimBoolean,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
HInstruction* field_get_in_loop_header = loop_header->GetLastInstruction();
loop_header->AddInstruction(new (&allocator) HIf(block->GetLastInstruction()));
@@ -174,13 +174,13 @@
HInstruction* field_set = loop_body->GetLastInstruction();
loop_body->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimBoolean,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
HInstruction* field_get_in_loop_body = loop_body->GetLastInstruction();
loop_body->AddInstruction(new (&allocator) HGoto());
exit->AddInstruction(
new (&allocator) HInstanceFieldGet(parameter, Primitive::kPrimBoolean,
- MemberOffset(42), false));
+ MemberOffset(42), false, false));
HInstruction* field_get_in_exit = exit->GetLastInstruction();
exit->AddInstruction(new (&allocator) HExit());
diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index 3fe23e1..51c68e9 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -2993,8 +2993,10 @@
HInstanceFieldGet(HInstruction* value,
Primitive::Type field_type,
MemberOffset field_offset,
+ bool is_final,
bool is_volatile)
- : HExpression(field_type, SideEffects::DependsOnSomething()),
+ : HExpression(field_type,
+ is_final ? SideEffects::None() : SideEffects::DependsOnSomething()),
field_info_(field_offset, field_type, is_volatile) {
SetRawInputAt(0, value);
}
@@ -3404,8 +3406,10 @@
HStaticFieldGet(HInstruction* cls,
Primitive::Type field_type,
MemberOffset field_offset,
+ bool is_final,
bool is_volatile)
- : HExpression(field_type, SideEffects::DependsOnSomething()),
+ : HExpression(field_type,
+ is_final ? SideEffects::None() : SideEffects::DependsOnSomething()),
field_info_(field_offset, field_type, is_volatile) {
SetRawInputAt(0, cls);
}
diff --git a/compiler/optimizing/register_allocator_test.cc b/compiler/optimizing/register_allocator_test.cc
index 8c6d904..61afb99 100644
--- a/compiler/optimizing/register_allocator_test.cc
+++ b/compiler/optimizing/register_allocator_test.cc
@@ -475,7 +475,7 @@
entry->AddSuccessor(block);
HInstruction* test = new (allocator) HInstanceFieldGet(
- parameter, Primitive::kPrimBoolean, MemberOffset(22), false);
+ parameter, Primitive::kPrimBoolean, MemberOffset(22), false, false);
block->AddInstruction(test);
block->AddInstruction(new (allocator) HIf(test));
HBasicBlock* then = new (allocator) HBasicBlock(graph);
@@ -495,9 +495,9 @@
*phi = new (allocator) HPhi(allocator, 0, 0, Primitive::kPrimInt);
join->AddPhi(*phi);
*input1 = new (allocator) HInstanceFieldGet(parameter, Primitive::kPrimInt,
- MemberOffset(42), false);
+ MemberOffset(42), false, false);
*input2 = new (allocator) HInstanceFieldGet(parameter, Primitive::kPrimInt,
- MemberOffset(42), false);
+ MemberOffset(42), false, false);
then->AddInstruction(*input1);
else_->AddInstruction(*input2);
join->AddInstruction(new (allocator) HExit());
@@ -605,7 +605,7 @@
entry->AddSuccessor(block);
*field = new (allocator) HInstanceFieldGet(parameter, Primitive::kPrimInt,
- MemberOffset(42), false);
+ MemberOffset(42), false, false);
block->AddInstruction(*field);
*ret = new (allocator) HReturn(*field);
block->AddInstruction(*ret);
diff --git a/test/483-checker-gvn/expected.txt b/test/483-checker-gvn/expected.txt
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/test/483-checker-gvn/expected.txt
diff --git a/test/483-checker-gvn/info.txt b/test/483-checker-gvn/info.txt
new file mode 100644
index 0000000..3ff7a8c
--- /dev/null
+++ b/test/483-checker-gvn/info.txt
@@ -0,0 +1 @@
+Tests that final fields can be GVNed even with side effects.
diff --git a/test/483-checker-gvn/src/Main.java b/test/483-checker-gvn/src/Main.java
new file mode 100644
index 0000000..ed474aa
--- /dev/null
+++ b/test/483-checker-gvn/src/Main.java
@@ -0,0 +1,62 @@
+/*
+* Copyright (C) 2015 The Android Open Source Project
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+public class Main {
+
+ public static final int staticField;
+ public final int instanceField;
+
+ Main() {
+ instanceField = 42;
+ }
+
+ static {
+ staticField = 42;
+ }
+
+ // CHECK-START: int Main.addStatic() GVN (before)
+ // CHECK-DAG: StaticFieldGet
+ // CHECK-DAG: StaticFieldGet
+
+ // CHECK-START: int Main.addStatic() GVN (after)
+ // CHECK-DAG: StaticFieldGet
+ // CHECK-NOT: StaticFieldGet
+ public static int addStatic() {
+ return staticField + doACall() + staticField;
+ }
+
+ // CHECK-START: int Main.addInstance() GVN (before)
+ // CHECK-DAG: InstanceFieldGet
+ // CHECK-DAG: InstanceFieldGet
+
+ // CHECK-START: int Main.addInstance() GVN (after)
+ // CHECK-DAG: InstanceFieldGet
+ // CHECK-NOT: InstanceFieldGet
+ public int addInstance() {
+ return instanceField + doACall() + instanceField;
+ }
+
+ public static int doACall() {
+ try {
+ // Defeat inlining.
+ Thread.sleep(0);
+ } catch (Throwable t ) {}
+ return (int) System.currentTimeMillis();
+ }
+
+ public static void main(String[] args) {
+ }
+}