Avoid visiting just eliminated bounds check.
Test: test-art-host
Bug: 32547652
Change-Id: Ifaed3d4eee08c6d044a41ade6c1ee73989489110
diff --git a/compiler/optimizing/bounds_check_elimination.cc b/compiler/optimizing/bounds_check_elimination.cc
index d2357a5..7dc094b 100644
--- a/compiler/optimizing/bounds_check_elimination.cc
+++ b/compiler/optimizing/bounds_check_elimination.cc
@@ -548,7 +548,21 @@
void VisitBasicBlock(HBasicBlock* block) OVERRIDE {
DCHECK(!IsAddedBlock(block));
first_index_bounds_check_map_.clear();
- HGraphVisitor::VisitBasicBlock(block);
+ // Visit phis and instructions using a safe iterator. The iteration protects
+ // against deleting the current instruction during iteration. However, it
+ // must advance next_ if that instruction is deleted during iteration.
+ for (HInstruction* instruction = block->GetFirstPhi(); instruction != nullptr;) {
+ DCHECK(instruction->IsInBlock());
+ next_ = instruction->GetNext();
+ instruction->Accept(this);
+ instruction = next_;
+ }
+ for (HInstruction* instruction = block->GetFirstInstruction(); instruction != nullptr;) {
+ DCHECK(instruction->IsInBlock());
+ next_ = instruction->GetNext();
+ instruction->Accept(this);
+ instruction = next_;
+ }
// We should never deoptimize from an osr method, otherwise we might wrongly optimize
// code dominated by the deoptimization.
if (!GetGraph()->IsCompilingOsr()) {
@@ -1798,7 +1812,12 @@
}
/** Helper method to replace an instruction with another instruction. */
- static void ReplaceInstruction(HInstruction* instruction, HInstruction* replacement) {
+ void ReplaceInstruction(HInstruction* instruction, HInstruction* replacement) {
+ // Safe iteration.
+ if (instruction == next_) {
+ next_ = next_->GetNext();
+ }
+ // Replace and remove.
instruction->ReplaceWith(replacement);
instruction->GetBlock()->RemoveInstruction(instruction);
}
@@ -1831,6 +1850,9 @@
// Range analysis based on induction variables.
InductionVarRange induction_range_;
+ // Safe iteration.
+ HInstruction* next_;
+
DISALLOW_COPY_AND_ASSIGN(BCEVisitor);
};