Clean up `HGraphVisitor::VisitBasicBlock()`.

Skip `HPhi::Accept()` and add functions to visit only Phis
or only non-Phi instructions.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 181943478
Change-Id: Iba0690ae70f46d6a2bafa9055b2ae5167e58a2f4

9 files changed, 26 insertions, 24 deletions

diff --git a/compiler/optimizing/constant_folding.cc b/compiler/optimizing/constant_folding.cc
index b0a65ca64d..f57d8ade16 100644
--- a/compiler/optimizing/constant_folding.cc
+++ b/compiler/optimizing/constant_folding.cc
@@ -117,12 +117,9 @@ bool HConstantFolding::Run() {
 
 
 void HConstantFoldingVisitor::VisitBasicBlock(HBasicBlock* block) {
-  // Traverse this block's instructions (phis don't need to be
-  // processed) in (forward) order and replace the ones that can be
-  // statically evaluated by a compile-time counterpart.
-  for (HInstructionIterator it(block->GetInstructions()); !it.Done(); it.Advance()) {
-    it.Current()->Accept(this);
-  }
+  // Traverse this block's instructions (phis don't need to be processed) in (forward) order
+  // and replace the ones that can be statically evaluated by a compile-time counterpart.
+  VisitNonPhiInstructions(block);
 }
 
 void HConstantFoldingVisitor::VisitUnaryOperation(HUnaryOperation* inst) {
diff --git a/compiler/optimizing/constructor_fence_redundancy_elimination.cc b/compiler/optimizing/constructor_fence_redundancy_elimination.cc
index 9b3bb91d21..30c33dd5c5 100644
--- a/compiler/optimizing/constructor_fence_redundancy_elimination.cc
+++ b/compiler/optimizing/constructor_fence_redundancy_elimination.cc
@@ -37,8 +37,8 @@ class CFREVisitor final : public HGraphVisitor {
         stats_(stats) {}
 
   void VisitBasicBlock(HBasicBlock* block) override {
-    // Visit all instructions in block.
-    HGraphVisitor::VisitBasicBlock(block);
+    // Visit all non-Phi instructions in the block.
+    VisitNonPhiInstructions(block);
 
     // If there were any unmerged fences left, merge them together,
     // the objects are considered 'published' at the end of the block.
diff --git a/compiler/optimizing/instruction_simplifier.cc b/compiler/optimizing/instruction_simplifier.cc
index 44d624883d..d39e9ad32f 100644
--- a/compiler/optimizing/instruction_simplifier.cc
+++ b/compiler/optimizing/instruction_simplifier.cc
@@ -170,7 +170,7 @@ bool InstructionSimplifierVisitor::Run() {
     // post order visit, we sometimes need to revisit an instruction index.
     do {
       simplification_occurred_ = false;
-      VisitBasicBlock(block);
+      VisitNonPhiInstructions(block);
       if (simplification_occurred_) {
         didSimplify = true;
       }
diff --git a/compiler/optimizing/load_store_elimination.cc b/compiler/optimizing/load_store_elimination.cc
index 09e23a8552..80cf9e669b 100644
--- a/compiler/optimizing/load_store_elimination.cc
+++ b/compiler/optimizing/load_store_elimination.cc
@@ -1834,8 +1834,8 @@ void LSEVisitor::VisitBasicBlock(HBasicBlock* block) {
   } else {
     MergePredecessorRecords(block);
   }
-  // Visit instructions.
-  HGraphVisitor::VisitBasicBlock(block);
+  // Visit non-Phi instructions.
+  VisitNonPhiInstructions(block);
 }
 
 bool LSEVisitor::MayAliasOnBackEdge(HBasicBlock* loop_header, size_t idx1, size_t idx2) const {
diff --git a/compiler/optimizing/nodes.cc b/compiler/optimizing/nodes.cc
index 94f197d8f1..c87c78815b 100644
--- a/compiler/optimizing/nodes.cc
+++ b/compiler/optimizing/nodes.cc
@@ -1693,10 +1693,20 @@ void HGraphVisitor::VisitReversePostOrder() {
 }
 
 void HGraphVisitor::VisitBasicBlock(HBasicBlock* block) {
+  VisitPhis(block);
+  VisitNonPhiInstructions(block);
+}
+
+void HGraphVisitor::VisitPhis(HBasicBlock* block) {
   for (HInstructionIterator it(block->GetPhis()); !it.Done(); it.Advance()) {
-    it.Current()->Accept(this);
+    DCHECK(it.Current()->IsPhi());
+    VisitPhi(it.Current()->AsPhi());
   }
+}
+
+void HGraphVisitor::VisitNonPhiInstructions(HBasicBlock* block) {
   for (HInstructionIterator it(block->GetInstructions()); !it.Done(); it.Advance()) {
+    DCHECK(!it.Current()->IsPhi());
     it.Current()->Accept(this);
   }
 }
diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index bf4a66dfc3..4d6b909629 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -8572,6 +8572,9 @@ class HGraphVisitor : public ValueObject {
 #undef DECLARE_VISIT_INSTRUCTION
 
  protected:
+  void VisitPhis(HBasicBlock* block);
+  void VisitNonPhiInstructions(HBasicBlock* block);
+
   OptimizingCompilerStats* stats_;
 
  private:
diff --git a/compiler/optimizing/profiling_info_builder.cc b/compiler/optimizing/profiling_info_builder.cc
index f6cf676813..7faf2bf5be 100644
--- a/compiler/optimizing/profiling_info_builder.cc
+++ b/compiler/optimizing/profiling_info_builder.cc
@@ -33,10 +33,7 @@ void ProfilingInfoBuilder::Run() {
   // Order does not matter.
   for (HBasicBlock* block : GetGraph()->GetReversePostOrder()) {
     // No need to visit the phis.
-    for (HInstructionIteratorHandleChanges inst_it(block->GetInstructions()); !inst_it.Done();
-         inst_it.Advance()) {
-      inst_it.Current()->Accept(this);
-    }
+    VisitNonPhiInstructions(block);
   }
 
   ScopedObjectAccess soa(Thread::Current());
diff --git a/compiler/optimizing/reference_type_propagation.cc b/compiler/optimizing/reference_type_propagation.cc
index 6f44d45ed4..91a6fd5d3a 100644
--- a/compiler/optimizing/reference_type_propagation.cc
+++ b/compiler/optimizing/reference_type_propagation.cc
@@ -316,16 +316,11 @@ bool ReferenceTypePropagation::Run() {
 
 void ReferenceTypePropagation::RTPVisitor::VisitBasicBlock(HBasicBlock* block) {
   // Handle Phis first as there might be instructions in the same block who depend on them.
-  for (HInstructionIterator it(block->GetPhis()); !it.Done(); it.Advance()) {
-    VisitPhi(it.Current()->AsPhi());
-  }
+  VisitPhis(block);
 
   // Handle instructions. Since RTP may add HBoundType instructions just after the
   // last visited instruction, use `HInstructionIteratorHandleChanges` iterator.
-  for (HInstructionIteratorHandleChanges it(block->GetInstructions()); !it.Done(); it.Advance()) {
-    HInstruction* instr = it.Current();
-    instr->Accept(this);
-  }
+  VisitNonPhiInstructions(block);
 
   // Add extra nodes to bound types.
   BoundTypeForIfNotNull(block);
diff --git a/compiler/optimizing/write_barrier_elimination.cc b/compiler/optimizing/write_barrier_elimination.cc
index 27348cd87d..220eb78e02 100644
--- a/compiler/optimizing/write_barrier_elimination.cc
+++ b/compiler/optimizing/write_barrier_elimination.cc
@@ -38,7 +38,7 @@ class WBEVisitor final : public HGraphVisitor {
     // We clear the map to perform this optimization only in the same block. Doing it across blocks
     // would entail non-trivial merging of states.
     current_write_barriers_.clear();
-    HGraphVisitor::VisitBasicBlock(block);
+    VisitNonPhiInstructions(block);
   }
 
   void VisitInstanceFieldSet(HInstanceFieldSet* instruction) override {