Optimizations around escape analysis. With tests.
Details:
(1) added new intrinsics
(2) implemented optimizations
more !can be null information
more null check removals
replace return-this uses with incoming parameter
remove dead StringBuffer/Builder calls (with escape analysis)
(3) Fixed exposed bug in CanBeMoved()
Performance gain:
This improves CafeineString by about 360%
(removes null check from first loop, eliminates second loop completely)
Test: test-art-host
Change-Id: Iaf16a1b9cab6a7386f43d71c6b51dd59600e81c1
diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index eebc49c..0734fd1 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -2072,6 +2072,8 @@
#undef INSTRUCTION_TYPE_CHECK
// Returns whether the instruction can be moved within the graph.
+ // TODO: this method is used by LICM and GVN with possibly different
+ // meanings? split and rename?
virtual bool CanBeMoved() const { return false; }
// Returns whether the two instructions are of the same kind.
@@ -3789,7 +3791,7 @@
bool CanThrow() const OVERRIDE { return GetPackedFlag<kFlagCanThrow>(); }
- bool CanBeMoved() const OVERRIDE { return IsIntrinsic(); }
+ bool CanBeMoved() const OVERRIDE { return IsIntrinsic() && !DoesAnyWrite(); }
bool InstructionDataEquals(const HInstruction* other) const OVERRIDE {
return intrinsic_ != Intrinsics::kNone && intrinsic_ == other->AsInvoke()->intrinsic_;
@@ -4181,6 +4183,19 @@
kVirtual),
vtable_index_(vtable_index) {}
+ bool CanBeNull() const OVERRIDE {
+ switch (GetIntrinsic()) {
+ case Intrinsics::kThreadCurrentThread:
+ case Intrinsics::kStringBufferAppend:
+ case Intrinsics::kStringBufferToString:
+ case Intrinsics::kStringBuilderAppend:
+ case Intrinsics::kStringBuilderToString:
+ return false;
+ default:
+ return HInvoke::CanBeNull();
+ }
+ }
+
bool CanDoImplicitNullCheckOn(HInstruction* obj) const OVERRIDE {
// TODO: Add implicit null checks in intrinsics.
return (obj == InputAt(0)) && !GetLocations()->Intrinsified();