Minor improvement on static BCE analysis.
Rationale:
Avoid testing initial range if nothing is known.
Change-Id: I22646a5fd6e4481245d1a2f57891d2805550489f
diff --git a/compiler/optimizing/bounds_check_elimination.cc b/compiler/optimizing/bounds_check_elimination.cc
index eee6116..c307522 100644
--- a/compiler/optimizing/bounds_check_elimination.cc
+++ b/compiler/optimizing/bounds_check_elimination.cc
@@ -1227,27 +1227,28 @@
InductionVarRange::Value v1;
InductionVarRange::Value v2;
bool needs_finite_test = false;
- induction_range_.GetInductionRange(context, index, &v1, &v2, &needs_finite_test);
- do {
- if (v1.is_known && (v1.a_constant == 0 || v1.a_constant == 1) &&
- v2.is_known && (v2.a_constant == 0 || v2.a_constant == 1)) {
- DCHECK(v1.a_constant == 1 || v1.instruction == nullptr);
- DCHECK(v2.a_constant == 1 || v2.instruction == nullptr);
- ValueRange index_range(GetGraph()->GetArena(),
- ValueBound(v1.instruction, v1.b_constant),
- ValueBound(v2.instruction, v2.b_constant));
- // If analysis reveals a certain OOB, disable dynamic BCE.
- if (index_range.GetLower().LessThan(array_range->GetLower()) ||
- index_range.GetUpper().GreaterThan(array_range->GetUpper())) {
- *try_dynamic_bce = false;
- return false;
+ if (induction_range_.GetInductionRange(context, index, &v1, &v2, &needs_finite_test)) {
+ do {
+ if (v1.is_known && (v1.a_constant == 0 || v1.a_constant == 1) &&
+ v2.is_known && (v2.a_constant == 0 || v2.a_constant == 1)) {
+ DCHECK(v1.a_constant == 1 || v1.instruction == nullptr);
+ DCHECK(v2.a_constant == 1 || v2.instruction == nullptr);
+ ValueRange index_range(GetGraph()->GetArena(),
+ ValueBound(v1.instruction, v1.b_constant),
+ ValueBound(v2.instruction, v2.b_constant));
+ // If analysis reveals a certain OOB, disable dynamic BCE.
+ if (index_range.GetLower().LessThan(array_range->GetLower()) ||
+ index_range.GetUpper().GreaterThan(array_range->GetUpper())) {
+ *try_dynamic_bce = false;
+ return false;
+ }
+ // Use analysis for static bce only if loop is finite.
+ if (!needs_finite_test && index_range.FitsIn(array_range)) {
+ return true;
+ }
}
- // Use analysis for static bce only if loop is finite.
- if (!needs_finite_test && index_range.FitsIn(array_range)) {
- return true;
- }
- }
- } while (induction_range_.RefineOuter(&v1, &v2));
+ } while (induction_range_.RefineOuter(&v1, &v2));
+ }
return false;
}