commit 372f10e5b0b34e2bb6e2b79aeba6c441e14afd1f
author Vladimir Marko <vmarko@google.com> Tue May 17 16:30:10 2016 +0100
committer Vladimir Marko <vmarko@google.com> Thu Jun 02 19:04:20 2016 +0100
tree 1f29c2467c8909ef0e0147f37f176caa1bcd2ccc
parent 1b66fdf3f33c72dfdda4d31f6f17b6a0d8607402

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

compiler/optimizing/nodes.cc

diff --git a/compiler/optimizing/nodes.cc b/compiler/optimizing/nodes.cc
index 60329cc..a1d243e 100644
--- a/compiler/optimizing/nodes.cc
+++ b/compiler/optimizing/nodes.cc
@@ -101,10 +101,7 @@
 }
 
 static void RemoveAsUser(HInstruction* instruction) {
-  for (size_t i = 0; i < instruction->InputCount(); i++) {
-    instruction->RemoveAsUserOfInput(i);
-  }
-
+  instruction->RemoveAsUserOfAllInputs();
   RemoveEnvironmentUses(instruction);
 }
 
@@ -748,8 +745,9 @@
 }
 
 static void UpdateInputsUsers(HInstruction* instruction) {
-  for (size_t i = 0, e = instruction->InputCount(); i < e; ++i) {
-    instruction->InputAt(i)->AddUseAt(instruction, i);
+  auto&& inputs = instruction->GetInputs();
+  for (size_t i = 0; i < inputs.size(); ++i) {
+    inputs[i]->AddUseAt(instruction, i);
   }
   // Environment should be created later.
   DCHECK(!instruction->HasEnvironment());
@@ -1117,9 +1115,10 @@
 void HPhi::RemoveInputAt(size_t index) {
   RemoveAsUserOfInput(index);
   inputs_.erase(inputs_.begin() + index);
-  for (size_t i = index, e = InputCount(); i < e; ++i) {
-    DCHECK_EQ(InputRecordAt(i).GetUseNode()->GetIndex(), i + 1u);
-    InputRecordAt(i).GetUseNode()->SetIndex(i);
+  // Update indexes in use nodes of inputs that have been pulled forward by the erase().
+  for (size_t i = index, e = inputs_.size(); i < e; ++i) {
+    DCHECK_EQ(inputs_[i].GetUseNode()->GetIndex(), i + 1u);
+    inputs_[i].GetUseNode()->SetIndex(i);
   }
 }
 
@@ -1315,16 +1314,18 @@
   return this == instruction->GetPreviousDisregardingMoves();
 }
 
-bool HInstruction::Equals(HInstruction* other) const {
+bool HInstruction::Equals(const HInstruction* other) const {
   if (!InstructionTypeEquals(other)) return false;
   DCHECK_EQ(GetKind(), other->GetKind());
   if (!InstructionDataEquals(other)) return false;
   if (GetType() != other->GetType()) return false;
-  if (InputCount() != other->InputCount()) return false;
-
-  for (size_t i = 0, e = InputCount(); i < e; ++i) {
-    if (InputAt(i) != other->InputAt(i)) return false;
+  auto&& inputs = GetInputs();
+  auto&& other_inputs = other->GetInputs();
+  if (inputs.size() != other_inputs.size()) return false;
+  for (size_t i = 0; i != inputs.size(); ++i) {
+    if (inputs[i] != other_inputs[i]) return false;
   }
+
   DCHECK_EQ(ComputeHashCode(), other->ComputeHashCode());
   return true;
 }
@@ -2383,9 +2384,9 @@
   inputs_.insert(inputs_.begin() + index, HUserRecord<HInstruction*>(input));
   input->AddUseAt(this, index);
   // Update indexes in use nodes of inputs that have been pushed further back by the insert().
-  for (size_t i = index + 1u, size = inputs_.size(); i != size; ++i) {
-    DCHECK_EQ(InputRecordAt(i).GetUseNode()->GetIndex(), i - 1u);
-    InputRecordAt(i).GetUseNode()->SetIndex(i);
+  for (size_t i = index + 1u, e = inputs_.size(); i < e; ++i) {
+    DCHECK_EQ(inputs_[i].GetUseNode()->GetIndex(), i - 1u);
+    inputs_[i].GetUseNode()->SetIndex(i);
   }
 }
 
@@ -2393,9 +2394,9 @@
   RemoveAsUserOfInput(index);
   inputs_.erase(inputs_.begin() + index);
   // Update indexes in use nodes of inputs that have been pulled forward by the erase().
-  for (size_t i = index, e = InputCount(); i < e; ++i) {
-    DCHECK_EQ(InputRecordAt(i).GetUseNode()->GetIndex(), i + 1u);
-    InputRecordAt(i).GetUseNode()->SetIndex(i);
+  for (size_t i = index, e = inputs_.size(); i < e; ++i) {
+    DCHECK_EQ(inputs_[i].GetUseNode()->GetIndex(), i + 1u);
+    inputs_[i].GetUseNode()->SetIndex(i);
   }
 }
 
@@ -2433,8 +2434,8 @@
   }
 }
 
-bool HLoadString::InstructionDataEquals(HInstruction* other) const {
-  HLoadString* other_load_string = other->AsLoadString();
+bool HLoadString::InstructionDataEquals(const HInstruction* other) const {
+  const HLoadString* other_load_string = other->AsLoadString();
   if (string_index_ != other_load_string->string_index_ ||
       GetPackedFields() != other_load_string->GetPackedFields()) {
     return false;