Generalize range analysis.
Rationale:
obvious case x+-1 vs x-1 was missing
Test: test-art-host
Bug: 63631713
Change-Id: I0a97548a509239bee34a099b1ce9856bac311dba
diff --git a/compiler/optimizing/induction_var_range.cc b/compiler/optimizing/induction_var_range.cc
index 089340e..191d3d1 100644
--- a/compiler/optimizing/induction_var_range.cc
+++ b/compiler/optimizing/induction_var_range.cc
@@ -670,6 +670,15 @@
return AddValue(GetFetch(instruction->InputAt(0), trip, in_body, is_min),
Value(static_cast<int32_t>(value)));
}
+ } else if (instruction->IsSub()) {
+ // Incorporate suitable constants in the chased value.
+ if (IsInt64AndGet(instruction->InputAt(0), &value) && CanLongValueFitIntoInt(value)) {
+ return SubValue(Value(static_cast<int32_t>(value)),
+ GetFetch(instruction->InputAt(1), trip, in_body, !is_min));
+ } else if (IsInt64AndGet(instruction->InputAt(1), &value) && CanLongValueFitIntoInt(value)) {
+ return SubValue(GetFetch(instruction->InputAt(0), trip, in_body, is_min),
+ Value(static_cast<int32_t>(value)));
+ }
} else if (instruction->IsArrayLength()) {
// Exploit length properties when chasing constants or chase into a new array declaration.
if (chase_hint_ == nullptr) {