Refactor handling of input records.
Introduce HInstruction::GetInputRecords(), a new virtual
function that returns an ArrayRef<> to all input records.
Implement all other functions dealing with input records as
wrappers around GetInputRecords(). Rewrite functions that
previously used multiple virtual calls to deal with input
records, especially in loops, to prefetch the ArrayRef<>
only once for each instruction. Besides avoiding all the
extra calls, this also allows the compiler (clang++) to
perform additional optimizations.
This speeds up the Nexus 5 boot image compilation by ~0.5s
(4% of "Compile Dex File", 2% of dex2oat time) on AOSP ToT.
Change-Id: Id8ebe0fb9405e38d918972a11bd724146e4ca578
diff --git a/compiler/optimizing/ssa_liveness_analysis.cc b/compiler/optimizing/ssa_liveness_analysis.cc
index 36e0d99..212d935 100644
--- a/compiler/optimizing/ssa_liveness_analysis.cc
+++ b/compiler/optimizing/ssa_liveness_analysis.cc
@@ -177,8 +177,9 @@
static void RecursivelyProcessInputs(HInstruction* current,
HInstruction* actual_user,
BitVector* live_in) {
- for (size_t i = 0, e = current->InputCount(); i < e; ++i) {
- HInstruction* input = current->InputAt(i);
+ auto&& inputs = current->GetInputs();
+ for (size_t i = 0; i < inputs.size(); ++i) {
+ HInstruction* input = inputs[i];
bool has_in_location = current->GetLocations()->InAt(i).IsValid();
bool has_out_location = input->GetLocations()->Out().IsValid();
@@ -430,12 +431,12 @@
// If the instruction dies at the phi assignment, we can try having the
// same register.
if (end == user->GetBlock()->GetPredecessors()[input_index]->GetLifetimeEnd()) {
- for (size_t i = 0, e = user->InputCount(); i < e; ++i) {
+ auto&& inputs = user->GetInputs();
+ for (size_t i = 0; i < inputs.size(); ++i) {
if (i == input_index) {
continue;
}
- HInstruction* input = user->InputAt(i);
- Location location = input->GetLiveInterval()->GetLocationAt(
+ Location location = inputs[i]->GetLiveInterval()->GetLocationAt(
user->GetBlock()->GetPredecessors()[i]->GetLifetimeEnd() - 1);
if (location.IsRegisterKind()) {
int reg = RegisterOrLowRegister(location);
@@ -471,10 +472,10 @@
if (defined_by_->IsPhi()) {
// Try to use the same register as one of the inputs.
const ArenaVector<HBasicBlock*>& predecessors = defined_by_->GetBlock()->GetPredecessors();
- for (size_t i = 0, e = defined_by_->InputCount(); i < e; ++i) {
- HInstruction* input = defined_by_->InputAt(i);
+ auto&& inputs = defined_by_->GetInputs();
+ for (size_t i = 0; i < inputs.size(); ++i) {
size_t end = predecessors[i]->GetLifetimeEnd();
- LiveInterval* input_interval = input->GetLiveInterval()->GetSiblingAt(end - 1);
+ LiveInterval* input_interval = inputs[i]->GetLiveInterval()->GetSiblingAt(end - 1);
if (input_interval->GetEnd() == end) {
// If the input dies at the end of the predecessor, we know its register can
// be reused.