Use range analysis for better trip count analysis
Rationale:
Marking more loops as always-taken avoids generating
unnecessary new top tests while marking more loops
are non-infinite enables more optimizations. This
CL helps with these improvements. Also, some more
code is shared between induction and range analysis
and a bug with refining ranges has been fixed.
Bug: 27151190
Change-Id: Iecc0d7f32ae4779ee5424cda9dcc20816220935e
diff --git a/compiler/optimizing/induction_var_analysis.cc b/compiler/optimizing/induction_var_analysis.cc
index 37f2d79..a1e1cde 100644
--- a/compiler/optimizing/induction_var_analysis.cc
+++ b/compiler/optimizing/induction_var_analysis.cc
@@ -379,7 +379,7 @@
Primitive::Type type) {
// Transfer over a shift left: treat shift by restricted constant as equivalent multiplication.
int64_t value = -1;
- if (a != nullptr && IsIntAndGet(b, &value)) {
+ if (a != nullptr && IsExact(b, &value)) {
// Obtain the constant needed for the multiplication. This yields an existing instruction
// if the constants is already there. Otherwise, this has a side effect on the HIR.
// The restriction on the shift factor avoids generating a negative constant
@@ -546,9 +546,10 @@
// Analyze condition with induction at left-hand-side (e.g. i < U).
InductionInfo* lower_expr = a->op_b;
InductionInfo* upper_expr = b;
- InductionInfo* stride = a->op_a;
+ InductionInfo* stride_expr = a->op_a;
+ // Constant stride?
int64_t stride_value = 0;
- if (!IsIntAndGet(stride, &stride_value)) {
+ if (!IsExact(stride_expr, &stride_value)) {
return;
}
// Rewrite condition i != U into i < U or i > U if end condition is reached exactly.
@@ -561,7 +562,7 @@
// stride < 0, either i > U or i >= U
if ((stride_value > 0 && (cmp == kCondLT || cmp == kCondLE)) ||
(stride_value < 0 && (cmp == kCondGT || cmp == kCondGE))) {
- VisitTripCount(loop, lower_expr, upper_expr, stride, stride_value, type, cmp);
+ VisitTripCount(loop, lower_expr, upper_expr, stride_expr, stride_value, type, cmp);
}
}
}
@@ -569,7 +570,7 @@
void HInductionVarAnalysis::VisitTripCount(HLoopInformation* loop,
InductionInfo* lower_expr,
InductionInfo* upper_expr,
- InductionInfo* stride,
+ InductionInfo* stride_expr,
int64_t stride_value,
Primitive::Type type,
IfCondition cmp) {
@@ -612,9 +613,10 @@
trip_count = CreateInvariantOp(kAdd, trip_count, CreateConstant(1, type));
}
// Compensate for stride.
- trip_count = CreateInvariantOp(kAdd, trip_count, stride);
+ trip_count = CreateInvariantOp(kAdd, trip_count, stride_expr);
}
- trip_count = CreateInvariantOp(kDiv, CreateInvariantOp(kSub, trip_count, lower_expr), stride);
+ trip_count = CreateInvariantOp(
+ kDiv, CreateInvariantOp(kSub, trip_count, lower_expr), stride_expr);
// Assign the trip-count expression to the loop control. Clients that use the information
// should be aware that the expression is only valid under the conditions listed above.
InductionOp tcKind = kTripCountInBodyUnsafe; // needs both tests
@@ -644,14 +646,25 @@
IfCondition cmp) {
int64_t lower_value;
int64_t upper_value;
- if (IsIntAndGet(lower_expr, &lower_value) && IsIntAndGet(upper_expr, &upper_value)) {
- switch (cmp) {
- case kCondLT: return lower_value < upper_value;
- case kCondLE: return lower_value <= upper_value;
- case kCondGT: return lower_value > upper_value;
- case kCondGE: return lower_value >= upper_value;
- default: LOG(FATAL) << "CONDITION UNREACHABLE";
- }
+ switch (cmp) {
+ case kCondLT:
+ return IsAtMost(lower_expr, &lower_value)
+ && IsAtLeast(upper_expr, &upper_value)
+ && lower_value < upper_value;
+ case kCondLE:
+ return IsAtMost(lower_expr, &lower_value)
+ && IsAtLeast(upper_expr, &upper_value)
+ && lower_value <= upper_value;
+ case kCondGT:
+ return IsAtLeast(lower_expr, &lower_value)
+ && IsAtMost(upper_expr, &upper_value)
+ && lower_value > upper_value;
+ case kCondGE:
+ return IsAtLeast(lower_expr, &lower_value)
+ && IsAtMost(upper_expr, &upper_value)
+ && lower_value >= upper_value;
+ default:
+ LOG(FATAL) << "CONDITION UNREACHABLE";
}
return false; // not certain, may be untaken
}
@@ -660,25 +673,23 @@
int64_t stride_value,
Primitive::Type type,
IfCondition cmp) {
- const int64_t min = type == Primitive::kPrimInt
- ? std::numeric_limits<int32_t>::min()
- : std::numeric_limits<int64_t>::min();
- const int64_t max = type == Primitive::kPrimInt
- ? std::numeric_limits<int32_t>::max()
- : std::numeric_limits<int64_t>::max();
+ const int64_t min = type == Primitive::kPrimInt ? std::numeric_limits<int32_t>::min()
+ : std::numeric_limits<int64_t>::min();
+ const int64_t max = type == Primitive::kPrimInt ? std::numeric_limits<int32_t>::max()
+ : std::numeric_limits<int64_t>::max();
// Some rules under which it is certain at compile-time that the loop is finite.
int64_t value;
switch (cmp) {
case kCondLT:
return stride_value == 1 ||
- (IsIntAndGet(upper_expr, &value) && value <= (max - stride_value + 1));
+ (IsAtMost(upper_expr, &value) && value <= (max - stride_value + 1));
case kCondLE:
- return (IsIntAndGet(upper_expr, &value) && value <= (max - stride_value));
+ return (IsAtMost(upper_expr, &value) && value <= (max - stride_value));
case kCondGT:
return stride_value == -1 ||
- (IsIntAndGet(upper_expr, &value) && value >= (min - stride_value - 1));
+ (IsAtLeast(upper_expr, &value) && value >= (min - stride_value - 1));
case kCondGE:
- return (IsIntAndGet(upper_expr, &value) && value >= (min - stride_value));
+ return (IsAtLeast(upper_expr, &value) && value >= (min - stride_value));
default:
LOG(FATAL) << "CONDITION UNREACHABLE";
}
@@ -733,7 +744,7 @@
// More exhaustive simplifications are done by later phases once induction nodes are
// translated back into HIR code (e.g. by loop optimizations or BCE).
int64_t value = -1;
- if (IsIntAndGet(a, &value)) {
+ if (IsExact(a, &value)) {
if (value == 0) {
// Simplify 0 + b = b, 0 * b = 0.
if (op == kAdd) {
@@ -750,7 +761,7 @@
}
}
}
- if (IsIntAndGet(b, &value)) {
+ if (IsExact(b, &value)) {
if (value == 0) {
// Simplify a + 0 = a, a - 0 = a, a * 0 = 0, -0 = 0.
if (op == kAdd || op == kSub) {
@@ -784,29 +795,16 @@
return new (graph_->GetArena()) InductionInfo(kInvariant, op, a, b, nullptr);
}
-bool HInductionVarAnalysis::IsIntAndGet(InductionInfo* info, int64_t* value) {
- if (info != nullptr && info->induction_class == kInvariant) {
- // A direct constant fetch.
- if (info->operation == kFetch) {
- DCHECK(info->fetch);
- if (info->fetch->IsIntConstant()) {
- *value = info->fetch->AsIntConstant()->GetValue();
- return true;
- } else if (info->fetch->IsLongConstant()) {
- *value = info->fetch->AsLongConstant()->GetValue();
- return true;
- }
- }
- // Use range analysis to resolve compound values.
- InductionVarRange range(this);
- int32_t min_val = 0;
- int32_t max_val = 0;
- if (range.IsConstantRange(info, &min_val, &max_val) && min_val == max_val) {
- *value = min_val;
- return true;
- }
- }
- return false;
+bool HInductionVarAnalysis::IsExact(InductionInfo* info, int64_t* value) {
+ return InductionVarRange(this).IsConstant(info, InductionVarRange::kExact, value);
+}
+
+bool HInductionVarAnalysis::IsAtMost(InductionInfo* info, int64_t* value) {
+ return InductionVarRange(this).IsConstant(info, InductionVarRange::kAtMost, value);
+}
+
+bool HInductionVarAnalysis::IsAtLeast(InductionInfo* info, int64_t* value) {
+ return InductionVarRange(this).IsConstant(info, InductionVarRange::kAtLeast, value);
}
bool HInductionVarAnalysis::InductionEqual(InductionInfo* info1,
diff --git a/compiler/optimizing/induction_var_analysis.h b/compiler/optimizing/induction_var_analysis.h
index 84d5d82..94d2646 100644
--- a/compiler/optimizing/induction_var_analysis.h
+++ b/compiler/optimizing/induction_var_analysis.h
@@ -189,7 +189,9 @@
InductionInfo* CreateSimplifiedInvariant(InductionOp op, InductionInfo* a, InductionInfo* b);
// Constants.
- bool IsIntAndGet(InductionInfo* info, int64_t* value);
+ bool IsExact(InductionInfo* info, /*out*/ int64_t* value);
+ bool IsAtMost(InductionInfo* info, /*out*/ int64_t* value);
+ bool IsAtLeast(InductionInfo* info, /*out*/ int64_t* value);
// Helpers.
static bool InductionEqual(InductionInfo* info1, InductionInfo* info2);
diff --git a/compiler/optimizing/induction_var_range.cc b/compiler/optimizing/induction_var_range.cc
index 9566c29..b162696 100644
--- a/compiler/optimizing/induction_var_range.cc
+++ b/compiler/optimizing/induction_var_range.cc
@@ -45,17 +45,14 @@
return c2 != 0 && CanLongValueFitIntoInt(static_cast<int64_t>(c1) / static_cast<int64_t>(c2));
}
-/** Returns true for 32/64-bit integral constant. */
-static bool IsIntAndGet(HInstruction* instruction, int32_t* value) {
+/** Returns true for 32/64-bit constant instruction. */
+static bool IsIntAndGet(HInstruction* instruction, int64_t* value) {
if (instruction->IsIntConstant()) {
*value = instruction->AsIntConstant()->GetValue();
return true;
} else if (instruction->IsLongConstant()) {
- const int64_t c = instruction->AsLongConstant()->GetValue();
- if (CanLongValueFitIntoInt(c)) {
- *value = static_cast<int32_t>(c);
- return true;
- }
+ *value = instruction->AsLongConstant()->GetValue();
+ return true;
}
return false;
}
@@ -65,8 +62,9 @@
* because length >= 0 is true. This makes it more likely the bound is useful to clients.
*/
static InductionVarRange::Value SimplifyMax(InductionVarRange::Value v) {
- int32_t value;
- if (v.a_constant > 1 &&
+ int64_t value;
+ if (v.is_known &&
+ v.a_constant > 1 &&
v.instruction->IsDiv() &&
v.instruction->InputAt(0)->IsArrayLength() &&
IsIntAndGet(v.instruction->InputAt(1), &value) && v.a_constant == value) {
@@ -75,6 +73,16 @@
return v;
}
+/** Helper method to test for a constant value. */
+static bool IsConstantValue(InductionVarRange::Value v) {
+ return v.is_known && v.a_constant == 0;
+}
+
+/** Helper method to test for same constant value. */
+static bool IsSameConstantValue(InductionVarRange::Value v1, InductionVarRange::Value v2) {
+ return IsConstantValue(v1) && IsConstantValue(v2) && v1.b_constant == v2.b_constant;
+}
+
/** Helper method to insert an instruction. */
static HInstruction* Insert(HBasicBlock* block, HInstruction* instruction) {
DCHECK(block != nullptr);
@@ -99,29 +107,45 @@
/*out*/Value* max_val,
/*out*/bool* needs_finite_test) {
HLoopInformation* loop = context->GetBlock()->GetLoopInformation(); // closest enveloping loop
- if (loop != nullptr) {
- // Set up loop information.
- HBasicBlock* header = loop->GetHeader();
- bool in_body = context->GetBlock() != header;
- HInductionVarAnalysis::InductionInfo* info =
- induction_analysis_->LookupInfo(loop, instruction);
- HInductionVarAnalysis::InductionInfo* trip =
- induction_analysis_->LookupInfo(loop, header->GetLastInstruction());
- // Find range.
- *min_val = GetVal(info, trip, in_body, /* is_min */ true);
- *max_val = SimplifyMax(GetVal(info, trip, in_body, /* is_min */ false));
- *needs_finite_test = NeedsTripCount(info) && IsUnsafeTripCount(trip);
- return true;
+ if (loop == nullptr) {
+ return false; // no loop
}
- return false; // Nothing known
+ HInductionVarAnalysis::InductionInfo* info = induction_analysis_->LookupInfo(loop, instruction);
+ if (info == nullptr) {
+ return false; // no induction information
+ }
+ // Set up loop information.
+ HBasicBlock* header = loop->GetHeader();
+ bool in_body = context->GetBlock() != header;
+ HInductionVarAnalysis::InductionInfo* trip =
+ induction_analysis_->LookupInfo(loop, header->GetLastInstruction());
+ // Find range.
+ *min_val = GetVal(info, trip, in_body, /* is_min */ true);
+ *max_val = SimplifyMax(GetVal(info, trip, in_body, /* is_min */ false));
+ *needs_finite_test = NeedsTripCount(info) && IsUnsafeTripCount(trip);
+ return true;
}
-bool InductionVarRange::RefineOuter(/*in-out*/Value* min_val, /*in-out*/Value* max_val) const {
- Value v1 = RefineOuter(*min_val, /* is_min */ true);
- Value v2 = RefineOuter(*max_val, /* is_min */ false);
- if (v1.instruction != min_val->instruction || v2.instruction != max_val->instruction) {
- *min_val = v1;
- *max_val = v2;
+bool InductionVarRange::RefineOuter(/*in-out*/ Value* min_val,
+ /*in-out*/ Value* max_val) const {
+ Value v1_min = RefineOuter(*min_val, /* is_min */ true);
+ Value v2_max = RefineOuter(*max_val, /* is_min */ false);
+ // The refined range is safe if both sides refine the same instruction. Otherwise, since two
+ // different ranges are combined, the new refined range is safe to pass back to the client if
+ // the extremes of the computed ranges ensure no arithmetic wrap-around anomalies occur.
+ if (min_val->instruction != max_val->instruction) {
+ Value v1_max = RefineOuter(*min_val, /* is_min */ false);
+ Value v2_min = RefineOuter(*max_val, /* is_min */ true);
+ if (!IsConstantValue(v1_max) ||
+ !IsConstantValue(v2_min) ||
+ v1_max.b_constant > v2_min.b_constant) {
+ return false;
+ }
+ }
+ // Did something change?
+ if (v1_min.instruction != min_val->instruction || v2_max.instruction != max_val->instruction) {
+ *min_val = v1_min;
+ *max_val = v2_max;
return true;
}
return false;
@@ -164,6 +188,38 @@
// Private class methods.
//
+bool InductionVarRange::IsConstant(HInductionVarAnalysis::InductionInfo* info,
+ ConstantRequest request,
+ /*out*/ int64_t *value) const {
+ if (info != nullptr) {
+ // A direct 32-bit or 64-bit constant fetch. This immediately satisfies
+ // any of the three requests (kExact, kAtMost, and KAtLeast).
+ if (info->induction_class == HInductionVarAnalysis::kInvariant &&
+ info->operation == HInductionVarAnalysis::kFetch) {
+ if (IsIntAndGet(info->fetch, value)) {
+ return true;
+ }
+ }
+ // Try range analysis while traversing outward on loops.
+ bool in_body = true; // no known trip count
+ Value v_min = GetVal(info, nullptr, in_body, /* is_min */ true);
+ Value v_max = GetVal(info, nullptr, in_body, /* is_min */ false);
+ do {
+ // Make sure *both* extremes are known to avoid arithmetic wrap-around anomalies.
+ if (IsConstantValue(v_min) && IsConstantValue(v_max) && v_min.b_constant <= v_max.b_constant) {
+ if ((request == kExact && v_min.b_constant == v_max.b_constant) || request == kAtMost) {
+ *value = v_max.b_constant;
+ return true;
+ } else if (request == kAtLeast) {
+ *value = v_min.b_constant;
+ return true;
+ }
+ }
+ } while (RefineOuter(&v_min, &v_max));
+ }
+ return false;
+}
+
bool InductionVarRange::NeedsTripCount(HInductionVarAnalysis::InductionInfo* info) const {
if (info != nullptr) {
if (info->induction_class == HInductionVarAnalysis::kLinear) {
@@ -206,12 +262,10 @@
if (trip != nullptr) {
HInductionVarAnalysis::InductionInfo* trip_expr = trip->op_a;
if (trip_expr->operation == HInductionVarAnalysis::kSub) {
- int32_t min_value = 0;
- int32_t stride_value = 0;
- if (IsConstantRange(info->op_a, &min_value, &stride_value) && min_value == stride_value) {
+ int64_t stride_value = 0;
+ if (IsConstant(info->op_a, kExact, &stride_value)) {
if (!is_min && stride_value == 1) {
- // Test original trip's negative operand (trip_expr->op_b) against
- // the offset of the linear induction.
+ // Test original trip's negative operand (trip_expr->op_b) against offset of induction.
if (HInductionVarAnalysis::InductionEqual(trip_expr->op_b, info->op_b)) {
// Analyze cancelled trip with just the positive operand (trip_expr->op_a).
HInductionVarAnalysis::InductionInfo cancelled_trip(
@@ -219,8 +273,7 @@
return GetVal(&cancelled_trip, trip, in_body, is_min);
}
} else if (is_min && stride_value == -1) {
- // Test original trip's positive operand (trip_expr->op_a) against
- // the offset of the linear induction.
+ // Test original trip's positive operand (trip_expr->op_a) against offset of induction.
if (HInductionVarAnalysis::InductionEqual(trip_expr->op_a, info->op_b)) {
// Analyze cancelled trip with just the negative operand (trip_expr->op_b).
HInductionVarAnalysis::InductionInfo neg(
@@ -248,14 +301,16 @@
bool is_min) const {
// Detect constants and chase the fetch a bit deeper into the HIR tree, so that it becomes
// more likely range analysis will compare the same instructions as terminal nodes.
- int32_t value;
- if (IsIntAndGet(instruction, &value)) {
- return Value(value);
+ int64_t value;
+ if (IsIntAndGet(instruction, &value) && CanLongValueFitIntoInt(value)) {
+ return Value(static_cast<int32_t>(value));
} else if (instruction->IsAdd()) {
- if (IsIntAndGet(instruction->InputAt(0), &value)) {
- return AddValue(Value(value), GetFetch(instruction->InputAt(1), trip, in_body, is_min));
- } else if (IsIntAndGet(instruction->InputAt(1), &value)) {
- return AddValue(GetFetch(instruction->InputAt(0), trip, in_body, is_min), Value(value));
+ if (IsIntAndGet(instruction->InputAt(0), &value) && CanLongValueFitIntoInt(value)) {
+ return AddValue(Value(static_cast<int32_t>(value)),
+ GetFetch(instruction->InputAt(1), trip, in_body, is_min));
+ } else if (IsIntAndGet(instruction->InputAt(1), &value) && CanLongValueFitIntoInt(value)) {
+ return AddValue(GetFetch(instruction->InputAt(0), trip, in_body, is_min),
+ Value(static_cast<int32_t>(value)));
}
} else if (instruction->IsArrayLength() && instruction->InputAt(0)->IsNewArray()) {
return GetFetch(instruction->InputAt(0)->InputAt(0), trip, in_body, is_min);
@@ -331,29 +386,30 @@
Value v1_max = GetVal(info1, trip, in_body, /* is_min */ false);
Value v2_min = GetVal(info2, trip, in_body, /* is_min */ true);
Value v2_max = GetVal(info2, trip, in_body, /* is_min */ false);
- // Try to refine certain failure.
- if (v1_min.a_constant && v1_max.a_constant) {
- v1_min = RefineOuter(v1_min, /* is_min */ true);
- v1_max = RefineOuter(v1_max, /* is_min */ false);
+ // Try to refine first operand.
+ if (!IsConstantValue(v1_min) && !IsConstantValue(v1_max)) {
+ RefineOuter(&v1_min, &v1_max);
}
- // Positive or negative range?
- if (v1_min.is_known && v1_min.a_constant == 0 && v1_min.b_constant >= 0) {
- // Positive range vs. positive or negative range.
- if (v2_min.is_known && v2_min.a_constant == 0 && v2_min.b_constant >= 0) {
- return is_min ? MulValue(v1_min, v2_min)
- : MulValue(v1_max, v2_max);
- } else if (v2_max.is_known && v2_max.a_constant == 0 && v2_max.b_constant <= 0) {
- return is_min ? MulValue(v1_max, v2_min)
- : MulValue(v1_min, v2_max);
+ // Constant times range.
+ if (IsSameConstantValue(v1_min, v1_max)) {
+ return MulRangeAndConstant(v2_min, v2_max, v1_min, is_min);
+ } else if (IsSameConstantValue(v2_min, v2_max)) {
+ return MulRangeAndConstant(v1_min, v1_max, v2_min, is_min);
+ }
+ // Positive range vs. positive or negative range.
+ if (IsConstantValue(v1_min) && v1_min.b_constant >= 0) {
+ if (IsConstantValue(v2_min) && v2_min.b_constant >= 0) {
+ return is_min ? MulValue(v1_min, v2_min) : MulValue(v1_max, v2_max);
+ } else if (IsConstantValue(v2_max) && v2_max.b_constant <= 0) {
+ return is_min ? MulValue(v1_max, v2_min) : MulValue(v1_min, v2_max);
}
- } else if (v1_max.is_known && v1_max.a_constant == 0 && v1_max.b_constant <= 0) {
- // Negative range vs. positive or negative range.
- if (v2_min.is_known && v2_min.a_constant == 0 && v2_min.b_constant >= 0) {
- return is_min ? MulValue(v1_min, v2_max)
- : MulValue(v1_max, v2_min);
- } else if (v2_max.is_known && v2_max.a_constant == 0 && v2_max.b_constant <= 0) {
- return is_min ? MulValue(v1_max, v2_max)
- : MulValue(v1_min, v2_min);
+ }
+ // Negative range vs. positive or negative range.
+ if (IsConstantValue(v1_max) && v1_max.b_constant <= 0) {
+ if (IsConstantValue(v2_min) && v2_min.b_constant >= 0) {
+ return is_min ? MulValue(v1_min, v2_max) : MulValue(v1_max, v2_min);
+ } else if (IsConstantValue(v2_max) && v2_max.b_constant <= 0) {
+ return is_min ? MulValue(v1_max, v2_max) : MulValue(v1_min, v2_min);
}
}
return Value();
@@ -368,43 +424,41 @@
Value v1_max = GetVal(info1, trip, in_body, /* is_min */ false);
Value v2_min = GetVal(info2, trip, in_body, /* is_min */ true);
Value v2_max = GetVal(info2, trip, in_body, /* is_min */ false);
- // Positive or negative range?
- if (v1_min.is_known && v1_min.a_constant == 0 && v1_min.b_constant >= 0) {
- // Positive range vs. positive or negative range.
- if (v2_min.is_known && v2_min.a_constant == 0 && v2_min.b_constant >= 0) {
- return is_min ? DivValue(v1_min, v2_max)
- : DivValue(v1_max, v2_min);
- } else if (v2_max.is_known && v2_max.a_constant == 0 && v2_max.b_constant <= 0) {
- return is_min ? DivValue(v1_max, v2_max)
- : DivValue(v1_min, v2_min);
+ // Range divided by constant.
+ if (IsSameConstantValue(v2_min, v2_max)) {
+ return DivRangeAndConstant(v1_min, v1_max, v2_min, is_min);
+ }
+ // Positive range vs. positive or negative range.
+ if (IsConstantValue(v1_min) && v1_min.b_constant >= 0) {
+ if (IsConstantValue(v2_min) && v2_min.b_constant >= 0) {
+ return is_min ? DivValue(v1_min, v2_max) : DivValue(v1_max, v2_min);
+ } else if (IsConstantValue(v2_max) && v2_max.b_constant <= 0) {
+ return is_min ? DivValue(v1_max, v2_max) : DivValue(v1_min, v2_min);
}
- } else if (v1_max.is_known && v1_max.a_constant == 0 && v1_max.b_constant <= 0) {
- // Negative range vs. positive or negative range.
- if (v2_min.is_known && v2_min.a_constant == 0 && v2_min.b_constant >= 0) {
- return is_min ? DivValue(v1_min, v2_min)
- : DivValue(v1_max, v2_max);
- } else if (v2_max.is_known && v2_max.a_constant == 0 && v2_max.b_constant <= 0) {
- return is_min ? DivValue(v1_max, v2_min)
- : DivValue(v1_min, v2_max);
+ }
+ // Negative range vs. positive or negative range.
+ if (IsConstantValue(v1_max) && v1_max.b_constant <= 0) {
+ if (IsConstantValue(v2_min) && v2_min.b_constant >= 0) {
+ return is_min ? DivValue(v1_min, v2_min) : DivValue(v1_max, v2_max);
+ } else if (IsConstantValue(v2_max) && v2_max.b_constant <= 0) {
+ return is_min ? DivValue(v1_max, v2_min) : DivValue(v1_min, v2_max);
}
}
return Value();
}
-bool InductionVarRange::IsConstantRange(HInductionVarAnalysis::InductionInfo* info,
- int32_t *min_value,
- int32_t *max_value) const {
- bool in_body = true; // no known trip count
- Value v_min = GetVal(info, nullptr, in_body, /* is_min */ true);
- Value v_max = GetVal(info, nullptr, in_body, /* is_min */ false);
- do {
- if (v_min.is_known && v_min.a_constant == 0 && v_max.is_known && v_max.a_constant == 0) {
- *min_value = v_min.b_constant;
- *max_value = v_max.b_constant;
- return true;
- }
- } while (RefineOuter(&v_min, &v_max));
- return false;
+InductionVarRange::Value InductionVarRange::MulRangeAndConstant(Value v_min,
+ Value v_max,
+ Value c,
+ bool is_min) const {
+ return is_min == (c.b_constant >= 0) ? MulValue(v_min, c) : MulValue(v_max, c);
+}
+
+InductionVarRange::Value InductionVarRange::DivRangeAndConstant(Value v_min,
+ Value v_max,
+ Value c,
+ bool is_min) const {
+ return is_min == (c.b_constant >= 0) ? DivValue(v_min, c) : DivValue(v_max, c);
}
InductionVarRange::Value InductionVarRange::AddValue(Value v1, Value v2) const {
@@ -471,22 +525,25 @@
}
InductionVarRange::Value InductionVarRange::RefineOuter(Value v, bool is_min) const {
- if (v.instruction != nullptr) {
- HLoopInformation* loop =
- v.instruction->GetBlock()->GetLoopInformation(); // closest enveloping loop
- if (loop != nullptr) {
- // Set up loop information.
- bool in_body = true; // use is always in body of outer loop
- HInductionVarAnalysis::InductionInfo* info =
- induction_analysis_->LookupInfo(loop, v.instruction);
- HInductionVarAnalysis::InductionInfo* trip =
- induction_analysis_->LookupInfo(loop, loop->GetHeader()->GetLastInstruction());
- // Try to refine "a x instruction + b" with outer loop range information on instruction.
- return AddValue(MulValue(Value(v.a_constant), GetVal(info, trip, in_body, is_min)),
- Value(v.b_constant));
- }
+ if (v.instruction == nullptr) {
+ return v; // nothing to refine
}
- return v;
+ HLoopInformation* loop =
+ v.instruction->GetBlock()->GetLoopInformation(); // closest enveloping loop
+ if (loop == nullptr) {
+ return v; // no loop
+ }
+ HInductionVarAnalysis::InductionInfo* info = induction_analysis_->LookupInfo(loop, v.instruction);
+ if (info == nullptr) {
+ return v; // no induction information
+ }
+ // Set up loop information.
+ HBasicBlock* header = loop->GetHeader();
+ bool in_body = true; // inner always in more outer
+ HInductionVarAnalysis::InductionInfo* trip =
+ induction_analysis_->LookupInfo(loop, header->GetLastInstruction());
+ // Try to refine "a x instruction + b" with outer loop range information on instruction.
+ return AddValue(MulValue(Value(v.a_constant), GetVal(info, trip, in_body, is_min)), Value(v.b_constant));
}
bool InductionVarRange::GenerateCode(HInstruction* context,
@@ -499,44 +556,45 @@
/*out*/bool* needs_finite_test,
/*out*/bool* needs_taken_test) const {
HLoopInformation* loop = context->GetBlock()->GetLoopInformation(); // closest enveloping loop
- if (loop != nullptr) {
- // Set up loop information.
- HBasicBlock* header = loop->GetHeader();
- bool in_body = context->GetBlock() != header;
- HInductionVarAnalysis::InductionInfo* info =
- induction_analysis_->LookupInfo(loop, instruction);
- if (info == nullptr) {
- return false; // nothing to analyze
- }
- HInductionVarAnalysis::InductionInfo* trip =
- induction_analysis_->LookupInfo(loop, header->GetLastInstruction());
- // Determine what tests are needed. A finite test is needed if the evaluation code uses the
- // trip-count and the loop maybe unsafe (because in such cases, the index could "overshoot"
- // the computed range). A taken test is needed for any unknown trip-count, even if evaluation
- // code does not use the trip-count explicitly (since there could be an implicit relation
- // between e.g. an invariant subscript and a not-taken condition).
- *needs_finite_test = NeedsTripCount(info) && IsUnsafeTripCount(trip);
- *needs_taken_test = IsBodyTripCount(trip);
- // Code generation for taken test: generate the code when requested or otherwise analyze
- // if code generation is feasible when taken test is needed.
- if (taken_test != nullptr) {
- return GenerateCode(
- trip->op_b, nullptr, graph, block, taken_test, in_body, /* is_min */ false);
- } else if (*needs_taken_test) {
- if (!GenerateCode(
- trip->op_b, nullptr, nullptr, nullptr, nullptr, in_body, /* is_min */ false)) {
- return false;
- }
- }
- // Code generation for lower and upper.
- return
- // Success on lower if invariant (not set), or code can be generated.
- ((info->induction_class == HInductionVarAnalysis::kInvariant) ||
- GenerateCode(info, trip, graph, block, lower, in_body, /* is_min */ true)) &&
- // And success on upper.
- GenerateCode(info, trip, graph, block, upper, in_body, /* is_min */ false);
+ if (loop == nullptr) {
+ return false; // no loop
}
- return false;
+ HInductionVarAnalysis::InductionInfo* info = induction_analysis_->LookupInfo(loop, instruction);
+ if (info == nullptr) {
+ return false; // no induction information
+ }
+ // Set up loop information.
+ HBasicBlock* header = loop->GetHeader();
+ bool in_body = context->GetBlock() != header;
+ HInductionVarAnalysis::InductionInfo* trip =
+ induction_analysis_->LookupInfo(loop, header->GetLastInstruction());
+ if (trip == nullptr) {
+ return false; // codegen relies on trip count
+ }
+ // Determine what tests are needed. A finite test is needed if the evaluation code uses the
+ // trip-count and the loop maybe unsafe (because in such cases, the index could "overshoot"
+ // the computed range). A taken test is needed for any unknown trip-count, even if evaluation
+ // code does not use the trip-count explicitly (since there could be an implicit relation
+ // between e.g. an invariant subscript and a not-taken condition).
+ *needs_finite_test = NeedsTripCount(info) && IsUnsafeTripCount(trip);
+ *needs_taken_test = IsBodyTripCount(trip);
+ // Code generation for taken test: generate the code when requested or otherwise analyze
+ // if code generation is feasible when taken test is needed.
+ if (taken_test != nullptr) {
+ return GenerateCode(trip->op_b, nullptr, graph, block, taken_test, in_body, /* is_min */ false);
+ } else if (*needs_taken_test) {
+ if (!GenerateCode(
+ trip->op_b, nullptr, nullptr, nullptr, nullptr, in_body, /* is_min */ false)) {
+ return false;
+ }
+ }
+ // Code generation for lower and upper.
+ return
+ // Success on lower if invariant (not set), or code can be generated.
+ ((info->induction_class == HInductionVarAnalysis::kInvariant) ||
+ GenerateCode(info, trip, graph, block, lower, in_body, /* is_min */ true)) &&
+ // And success on upper.
+ GenerateCode(info, trip, graph, block, upper, in_body, /* is_min */ false);
}
bool InductionVarRange::GenerateCode(HInductionVarAnalysis::InductionInfo* info,
@@ -639,9 +697,8 @@
case HInductionVarAnalysis::kLinear: {
// Linear induction a * i + b, for normalized 0 <= i < TC. Restrict to unit stride only
// to avoid arithmetic wrap-around situations that are hard to guard against.
- int32_t min_value = 0;
- int32_t stride_value = 0;
- if (IsConstantRange(info->op_a, &min_value, &stride_value) && min_value == stride_value) {
+ int64_t stride_value = 0;
+ if (IsConstant(info->op_a, kExact, &stride_value)) {
if (stride_value == 1 || stride_value == -1) {
const bool is_min_a = stride_value == 1 ? is_min : !is_min;
if (GenerateCode(trip, trip, graph, block, &opa, in_body, is_min_a) &&
@@ -666,7 +723,7 @@
// Wrap-around and periodic inductions are restricted to constants only, so that extreme
// values are easy to test at runtime without complications of arithmetic wrap-around.
Value extreme = GetVal(info, trip, in_body, is_min);
- if (extreme.is_known && extreme.a_constant == 0) {
+ if (IsConstantValue(extreme)) {
if (graph != nullptr) {
*result = graph->GetIntConstant(extreme.b_constant);
}
diff --git a/compiler/optimizing/induction_var_range.h b/compiler/optimizing/induction_var_range.h
index 3cb7b4b..0af4156 100644
--- a/compiler/optimizing/induction_var_range.h
+++ b/compiler/optimizing/induction_var_range.h
@@ -69,7 +69,8 @@
/*out*/ bool* needs_finite_test);
/** Refines the values with induction of next outer loop. Returns true on change. */
- bool RefineOuter(/*in-out*/Value* min_val, /*in-out*/Value* max_val) const;
+ bool RefineOuter(/*in-out*/ Value* min_val,
+ /*in-out*/ Value* max_val) const;
/**
* Returns true if range analysis is able to generate code for the lower and upper
@@ -116,6 +117,23 @@
/*out*/ HInstruction** taken_test);
private:
+ /*
+ * Enum used in IsConstant() request.
+ */
+ enum ConstantRequest {
+ kExact,
+ kAtMost,
+ kAtLeast
+ };
+
+ /**
+ * Returns true if exact or upper/lower bound on the given induction
+ * information is known as a 64-bit constant, which is returned in value.
+ */
+ bool IsConstant(HInductionVarAnalysis::InductionInfo* info,
+ ConstantRequest request,
+ /*out*/ int64_t *value) const;
+
bool NeedsTripCount(HInductionVarAnalysis::InductionInfo* info) const;
bool IsBodyTripCount(HInductionVarAnalysis::InductionInfo* trip) const;
bool IsUnsafeTripCount(HInductionVarAnalysis::InductionInfo* trip) const;
@@ -143,9 +161,8 @@
bool in_body,
bool is_min) const;
- bool IsConstantRange(HInductionVarAnalysis::InductionInfo* info,
- int32_t *min_value,
- int32_t *max_value) const;
+ Value MulRangeAndConstant(Value v1, Value v2, Value c, bool is_min) const;
+ Value DivRangeAndConstant(Value v1, Value v2, Value c, bool is_min) const;
Value AddValue(Value v1, Value v2) const;
Value SubValue(Value v1, Value v2) const;
diff --git a/compiler/optimizing/induction_var_range_test.cc b/compiler/optimizing/induction_var_range_test.cc
index 55a654e..c5c33bd 100644
--- a/compiler/optimizing/induction_var_range_test.cc
+++ b/compiler/optimizing/induction_var_range_test.cc
@@ -215,10 +215,16 @@
return range_.GetDiv(info1, info2, nullptr, /* in_body */ true, is_min);
}
- bool IsConstantRange(HInductionVarAnalysis::InductionInfo* info,
- int32_t* min_value,
- int32_t* max_value) {
- return range_.IsConstantRange(info, min_value, max_value);
+ bool IsExact(HInductionVarAnalysis::InductionInfo* info, int64_t* value) {
+ return range_.IsConstant(info, InductionVarRange::kExact, value);
+ }
+
+ bool IsAtMost(HInductionVarAnalysis::InductionInfo* info, int64_t* value) {
+ return range_.IsConstant(info, InductionVarRange::kAtMost, value);
+ }
+
+ bool IsAtLeast(HInductionVarAnalysis::InductionInfo* info, int64_t* value) {
+ return range_.IsConstant(info, InductionVarRange::kAtLeast, value);
}
Value AddValue(Value v1, Value v2) { return range_.AddValue(v1, v2); }
@@ -249,6 +255,34 @@
// Tests on private methods.
//
+TEST_F(InductionVarRangeTest, IsConstant) {
+ int64_t value;
+ // Constant.
+ EXPECT_TRUE(IsExact(CreateConst(12345), &value));
+ EXPECT_EQ(12345, value);
+ EXPECT_TRUE(IsAtMost(CreateConst(12345), &value));
+ EXPECT_EQ(12345, value);
+ EXPECT_TRUE(IsAtLeast(CreateConst(12345), &value));
+ EXPECT_EQ(12345, value);
+ // Constant trivial range.
+ EXPECT_TRUE(IsExact(CreateRange(111, 111), &value));
+ EXPECT_EQ(111, value);
+ EXPECT_TRUE(IsAtMost(CreateRange(111, 111), &value));
+ EXPECT_EQ(111, value);
+ EXPECT_TRUE(IsAtLeast(CreateRange(111, 111), &value));
+ EXPECT_EQ(111, value);
+ // Constant non-trivial range.
+ EXPECT_FALSE(IsExact(CreateRange(11, 22), &value));
+ EXPECT_TRUE(IsAtMost(CreateRange(11, 22), &value));
+ EXPECT_EQ(22, value);
+ EXPECT_TRUE(IsAtLeast(CreateRange(11, 22), &value));
+ EXPECT_EQ(11, value);
+ // Symbolic.
+ EXPECT_FALSE(IsExact(CreateFetch(x_), &value));
+ EXPECT_FALSE(IsAtMost(CreateFetch(x_), &value));
+ EXPECT_FALSE(IsAtLeast(CreateFetch(x_), &value));
+}
+
TEST_F(InductionVarRangeTest, TripCountProperties) {
EXPECT_FALSE(NeedsTripCount(nullptr));
EXPECT_FALSE(NeedsTripCount(CreateConst(1)));
@@ -367,6 +401,10 @@
}
TEST_F(InductionVarRangeTest, GetMulMin) {
+ ExpectEqual(Value(-14), GetMul(CreateConst(2), CreateRange(-7, 8), true));
+ ExpectEqual(Value(-16), GetMul(CreateConst(-2), CreateRange(-7, 8), true));
+ ExpectEqual(Value(-14), GetMul(CreateRange(-7, 8), CreateConst(2), true));
+ ExpectEqual(Value(-16), GetMul(CreateRange(-7, 8), CreateConst(-2), true));
ExpectEqual(Value(6), GetMul(CreateRange(2, 10), CreateRange(3, 5), true));
ExpectEqual(Value(-50), GetMul(CreateRange(2, 10), CreateRange(-5, -3), true));
ExpectEqual(Value(), GetMul(CreateRange(2, 10), CreateRange(-1, 1), true));
@@ -379,6 +417,10 @@
}
TEST_F(InductionVarRangeTest, GetMulMax) {
+ ExpectEqual(Value(16), GetMul(CreateConst(2), CreateRange(-7, 8), false));
+ ExpectEqual(Value(14), GetMul(CreateConst(-2), CreateRange(-7, 8), false));
+ ExpectEqual(Value(16), GetMul(CreateRange(-7, 8), CreateConst(2), false));
+ ExpectEqual(Value(14), GetMul(CreateRange(-7, 8), CreateConst(-2), false));
ExpectEqual(Value(50), GetMul(CreateRange(2, 10), CreateRange(3, 5), false));
ExpectEqual(Value(-6), GetMul(CreateRange(2, 10), CreateRange(-5, -3), false));
ExpectEqual(Value(), GetMul(CreateRange(2, 10), CreateRange(-1, 1), false));
@@ -391,6 +433,8 @@
}
TEST_F(InductionVarRangeTest, GetDivMin) {
+ ExpectEqual(Value(-5), GetDiv(CreateRange(-10, 20), CreateConst(2), true));
+ ExpectEqual(Value(-10), GetDiv(CreateRange(-10, 20), CreateConst(-2), true));
ExpectEqual(Value(10), GetDiv(CreateRange(40, 1000), CreateRange(2, 4), true));
ExpectEqual(Value(-500), GetDiv(CreateRange(40, 1000), CreateRange(-4, -2), true));
ExpectEqual(Value(), GetDiv(CreateRange(40, 1000), CreateRange(-1, 1), true));
@@ -403,6 +447,8 @@
}
TEST_F(InductionVarRangeTest, GetDivMax) {
+ ExpectEqual(Value(10), GetDiv(CreateRange(-10, 20), CreateConst(2), false));
+ ExpectEqual(Value(5), GetDiv(CreateRange(-10, 20), CreateConst(-2), false));
ExpectEqual(Value(500), GetDiv(CreateRange(40, 1000), CreateRange(2, 4), false));
ExpectEqual(Value(-10), GetDiv(CreateRange(40, 1000), CreateRange(-4, -2), false));
ExpectEqual(Value(), GetDiv(CreateRange(40, 1000), CreateRange(-1, 1), false));
@@ -414,18 +460,6 @@
ExpectEqual(Value(), GetDiv(CreateRange(-1, 1), CreateRange(-1, 1), false));
}
-TEST_F(InductionVarRangeTest, IsConstantRange) {
- int32_t min_value;
- int32_t max_value;
- ASSERT_TRUE(IsConstantRange(CreateConst(12345), &min_value, &max_value));
- EXPECT_EQ(12345, min_value);
- EXPECT_EQ(12345, max_value);
- ASSERT_TRUE(IsConstantRange(CreateRange(1, 2), &min_value, &max_value));
- EXPECT_EQ(1, min_value);
- EXPECT_EQ(2, max_value);
- EXPECT_FALSE(IsConstantRange(CreateFetch(x_), &min_value, &max_value));
-}
-
TEST_F(InductionVarRangeTest, AddValue) {
ExpectEqual(Value(110), AddValue(Value(10), Value(100)));
ExpectEqual(Value(-5), AddValue(Value(x_, 1, -4), Value(x_, -1, -1)));
@@ -459,6 +493,24 @@
ExpectEqual(Value(), MulValue(Value(90000), Value(-90000))); // unsafe
}
+TEST_F(InductionVarRangeTest, MulValueSpecial) {
+ const int32_t min_value = std::numeric_limits<int32_t>::min();
+ const int32_t max_value = std::numeric_limits<int32_t>::max();
+
+ // Unsafe.
+ ExpectEqual(Value(), MulValue(Value(min_value), Value(min_value)));
+ ExpectEqual(Value(), MulValue(Value(min_value), Value(-1)));
+ ExpectEqual(Value(), MulValue(Value(min_value), Value(max_value)));
+ ExpectEqual(Value(), MulValue(Value(max_value), Value(max_value)));
+
+ // Safe.
+ ExpectEqual(Value(min_value), MulValue(Value(min_value), Value(1)));
+ ExpectEqual(Value(max_value), MulValue(Value(max_value), Value(1)));
+ ExpectEqual(Value(-max_value), MulValue(Value(max_value), Value(-1)));
+ ExpectEqual(Value(-1), MulValue(Value(1), Value(-1)));
+ ExpectEqual(Value(1), MulValue(Value(-1), Value(-1)));
+}
+
TEST_F(InductionVarRangeTest, DivValue) {
ExpectEqual(Value(25), DivValue(Value(100), Value(4)));
ExpectEqual(Value(), DivValue(Value(x_, 1, -4), Value(x_, 1, -1)));
@@ -468,6 +520,23 @@
ExpectEqual(Value(), DivValue(Value(1), Value(0))); // unsafe
}
+TEST_F(InductionVarRangeTest, DivValueSpecial) {
+ const int32_t min_value = std::numeric_limits<int32_t>::min();
+ const int32_t max_value = std::numeric_limits<int32_t>::max();
+
+ // Unsafe.
+ ExpectEqual(Value(), DivValue(Value(min_value), Value(-1)));
+
+ // Safe.
+ ExpectEqual(Value(1), DivValue(Value(min_value), Value(min_value)));
+ ExpectEqual(Value(1), DivValue(Value(max_value), Value(max_value)));
+ ExpectEqual(Value(min_value), DivValue(Value(min_value), Value(1)));
+ ExpectEqual(Value(max_value), DivValue(Value(max_value), Value(1)));
+ ExpectEqual(Value(-max_value), DivValue(Value(max_value), Value(-1)));
+ ExpectEqual(Value(-1), DivValue(Value(1), Value(-1)));
+ ExpectEqual(Value(1), DivValue(Value(-1), Value(-1)));
+}
+
TEST_F(InductionVarRangeTest, MinValue) {
ExpectEqual(Value(10), MinValue(Value(10), Value(100)));
ExpectEqual(Value(x_, 1, -4), MinValue(Value(x_, 1, -4), Value(x_, 1, -1)));
diff --git a/test/530-checker-loops/src/Main.java b/test/530-checker-loops/src/Main.java
index deff279..9f344dd 100644
--- a/test/530-checker-loops/src/Main.java
+++ b/test/530-checker-loops/src/Main.java
@@ -471,7 +471,7 @@
//
/// CHECK-START: void Main.linearTriangularOnTwoArrayLengths(int) BCE (after)
/// CHECK-NOT: BoundsCheck
- /// CHECK-NOT: Deoptimize
+ // TODO: also CHECK-NOT: Deoptimize, see b/27151190
private static void linearTriangularOnTwoArrayLengths(int n) {
int[] a = new int[n];
for (int i = 0; i < a.length; i++) {
@@ -513,7 +513,7 @@
//
/// CHECK-START: void Main.linearTriangularOnParameter(int) BCE (after)
/// CHECK-NOT: BoundsCheck
- /// CHECK-NOT: Deoptimize
+ // TODO: also CHECK-NOT: Deoptimize, see b/27151190
private static void linearTriangularOnParameter(int n) {
int[] a = new int[n];
for (int i = 0; i < n; i++) {
@@ -528,22 +528,22 @@
}
}
- /// CHECK-START: void Main.linearTriangularVariations(int) BCE (before)
+ /// CHECK-START: void Main.linearTriangularVariationsInnerStrict(int) BCE (before)
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
//
- /// CHECK-START: void Main.linearTriangularVariations(int) BCE (after)
+ /// CHECK-START: void Main.linearTriangularVariationsInnerStrict(int) BCE (after)
/// CHECK-NOT: BoundsCheck
- /// CHECK-NOT: Deoptimize
- private static void linearTriangularVariations(int n) {
+ // TODO: also CHECK-NOT: Deoptimize, see b/27151190
+ private static void linearTriangularVariationsInnerStrict(int n) {
int[] a = new int[n];
for (int i = 0; i < n; i++) {
for (int j = 0; j < i; j++) {
a[j] += 1;
}
- for (int j = i - 1; j >= 0; j--) {
+ for (int j = i - 1; j > -1; j--) {
a[j] += 1;
}
for (int j = i; j < n; j++) {
@@ -556,6 +556,34 @@
verifyTriangular(a);
}
+ /// CHECK-START: void Main.linearTriangularVariationsInnerNonStrict(int) BCE (before)
+ /// CHECK-DAG: BoundsCheck
+ /// CHECK-DAG: BoundsCheck
+ /// CHECK-DAG: BoundsCheck
+ /// CHECK-DAG: BoundsCheck
+ //
+ /// CHECK-START: void Main.linearTriangularVariationsInnerNonStrict(int) BCE (after)
+ /// CHECK-NOT: BoundsCheck
+ // TODO: also CHECK-NOT: Deoptimize, see b/27151190
+ private static void linearTriangularVariationsInnerNonStrict(int n) {
+ int[] a = new int[n];
+ for (int i = 0; i < n; i++) {
+ for (int j = 0; j <= i - 1; j++) {
+ a[j] += 1;
+ }
+ for (int j = i - 1; j >= 0; j--) {
+ a[j] += 1;
+ }
+ for (int j = i; j <= n - 1; j++) {
+ a[j] += 1;
+ }
+ for (int j = n - 1; j >= i; j--) {
+ a[j] += 1;
+ }
+ }
+ verifyTriangular(a);
+ }
+
// Verifier for triangular loops.
private static void verifyTriangular(int[] a, int[] b, int m, int n) {
expectEquals(n, a.length);
@@ -583,7 +611,7 @@
//
/// CHECK-START: void Main.bubble(int[]) BCE (after)
/// CHECK-NOT: BoundsCheck
- /// CHECK-NOT: Deoptimize
+ // TODO: also CHECK-NOT: Deoptimize, see b/27151190
private static void bubble(int[] a) {
for (int i = a.length; --i >= 0;) {
for (int j = 0; j < i; j++) {
@@ -853,6 +881,104 @@
} while (-1 <= i);
}
+ /// CHECK-START: void Main.hiddenOOB1(int) BCE (before)
+ /// CHECK-DAG: BoundsCheck
+ //
+ /// CHECK-START: void Main.hiddenOOB1(int) BCE (after)
+ /// CHECK-DAG: Deoptimize
+ //
+ /// CHECK-START: void Main.hiddenOOB1(int) BCE (after)
+ /// CHECK-NOT: BoundsCheck
+ private static void hiddenOOB1(int lo) {
+ int[] a = { 1 } ;
+ for (int i = lo; i <= 10; i++) {
+ // Dangerous loop where careless static range analysis would yield strict upper bound
+ // on index j of 5. When, for instance, lo and thus i = -2147483648, the upper bound
+ // becomes really positive due to arithmetic wrap-around, causing OOB.
+ // Dynamic BCE is feasible though, since it checks the range.
+ for (int j = 4; j < i - 5; j++) {
+ sResult += a[j - 4];
+ }
+ }
+ }
+
+ /// CHECK-START: void Main.hiddenOOB2(int) BCE (before)
+ /// CHECK-DAG: BoundsCheck
+ //
+ /// CHECK-START: void Main.hiddenOOB2(int) BCE (after)
+ /// CHECK-DAG: Deoptimize
+ //
+ /// CHECK-START: void Main.hiddenOOB2(int) BCE (after)
+ /// CHECK-NOT: BoundsCheck
+ private static void hiddenOOB2(int hi) {
+ int[] a = { 1 } ;
+ for (int i = 0; i < hi; i++) {
+ // Dangerous loop where careless static range analysis would yield strict lower bound
+ // on index j of 5. When, for instance, lo and thus i = 2147483647, the upper bound
+ // becomes really negative due to arithmetic wrap-around, causing OOB.
+ // Dynamic BCE is feasible though, since it checks the range.
+ for (int j = 6; j > i + 5; j--) {
+ sResult += a[j - 6];
+ }
+ }
+ }
+
+ /// CHECK-START: void Main.hiddenInfiniteOOB() BCE (before)
+ /// CHECK-DAG: BoundsCheck
+ //
+ /// CHECK-START: void Main.hiddenInfiniteOOB() BCE (after)
+ /// CHECK-DAG: BoundsCheck
+ //
+ /// CHECK-START: void Main.hiddenInfiniteOOB() BCE (after)
+ /// CHECK-NOT: Deoptimize
+ private static void hiddenInfiniteOOB() {
+ int[] a = { 11 } ;
+ for (int i = -1; i <= 0; i++) {
+ // Dangerous loop where careless static range analysis would yield a safe upper bound
+ // of -3. In reality, due to arithmetic wrap-around (when i = -1, j <= 2147483647;
+ // whereas when i = 0, j <= -3), this is an infinite loop that goes OOB.
+ for (int j = -3; j <= 2147483646 * i - 3; j++) {
+ sResult += a[j + 3];
+ }
+ }
+ }
+
+ /// CHECK-START: void Main.hiddenFiniteOOB() BCE (before)
+ /// CHECK-DAG: BoundsCheck
+ //
+ /// CHECK-START: void Main.hiddenFiniteOOB() BCE (after)
+ /// CHECK-DAG: Deoptimize
+ //
+ /// CHECK-START: void Main.hiddenFiniteOOB() BCE (after)
+ /// CHECK-NOT: BoundsCheck
+ private static void hiddenFiniteOOB() {
+ int[] a = { 111 } ;
+ for (int i = -1; i <= 0; i++) {
+ // Dangerous loop similar as above where the loop is now finite, but the
+ // loop still goes out of bounds for i = -1 due to the large upper bound.
+ // Dynamic BCE is feasible though, since it checks the range.
+ for (int j = -4; j < 2147483646 * i - 3; j++) {
+ sResult += a[j + 4];
+ }
+ }
+ }
+
+ /// CHECK-START: int[] Main.add() BCE (before)
+ /// CHECK-DAG: BoundsCheck
+ //
+ /// CHECK-START: int[] Main.add() BCE (after)
+ /// CHECK-NOT: BoundsCheck
+ /// CHECK-NOT: Deoptimize
+ private static int[] add() {
+ int[] a = new int[10];
+ for (int i = 0; i <= 3; i++) {
+ for (int j = 0; j <= 6; j++) {
+ a[i + j] += 1;
+ }
+ }
+ return a;
+ }
+
/// CHECK-START: int[] Main.multiply1() BCE (before)
/// CHECK-DAG: BoundsCheck
//
@@ -1053,6 +1179,37 @@
return result;
}
+ /// CHECK-START: int Main.dynamicBCEConstantRange(int[]) BCE (before)
+ /// CHECK-DAG: BoundsCheck loop:<<InnerLoop:B\d+>>
+ /// CHECK-DAG: ArrayGet loop:<<InnerLoop>>
+ /// CHECK-DAG: If loop:<<InnerLoop>>
+ /// CHECK-DAG: If loop:<<OuterLoop:B\d+>>
+ /// CHECK-EVAL: "<<InnerLoop>>" != "<<OuterLoop>>"
+ //
+ /// CHECK-START: int Main.dynamicBCEConstantRange(int[]) BCE (after)
+ /// CHECK-DAG: ArrayGet loop:<<InnerLoop:B\d+>>
+ /// CHECK-DAG: Deoptimize loop:<<OuterLoop:B\d+>>
+ /// CHECK-EVAL: "<<InnerLoop>>" != "<<OuterLoop>>"
+ //
+ /// CHECK-START: int Main.dynamicBCEConstantRange(int[]) BCE (after)
+ /// CHECK-NOT: BoundsCheck
+ //
+ // No additional top tests were introduced.
+ /// CHECK-START: int Main.dynamicBCEConstantRange(int[]) BCE (after)
+ /// CHECK-DAG: If
+ /// CHECK-DAG: If
+ /// CHECK-NOT: If
+ static int dynamicBCEConstantRange(int[] x) {
+ int result = 0;
+ for (int i = 2; i <= 6; i++) {
+ // Range analysis sees that innermost loop is finite and always taken.
+ for (int j = i - 2; j <= i + 2; j++) {
+ result += x[j];
+ }
+ }
+ return result;
+ }
+
/// CHECK-START: int Main.dynamicBCEAndConstantIndices(int[], int[][], int, int) BCE (before)
/// CHECK-DAG: {{l\d+}} ArrayGet loop:<<Loop:B\d+>>
/// CHECK-DAG: {{l\d+}} ArrayGet loop:<<Loop>>
@@ -1239,7 +1396,8 @@
linearTriangularOnTwoArrayLengths(10);
linearTriangularOnOneArrayLength(10);
linearTriangularOnParameter(10);
- linearTriangularVariations(10);
+ linearTriangularVariationsInnerStrict(10);
+ linearTriangularVariationsInnerNonStrict(10);
// Sorting.
int[] sort = { 5, 4, 1, 9, 10, 2, 7, 6, 3, 8 };
@@ -1330,6 +1488,59 @@
}
expectEquals(1055, sResult);
+ // Hidden OOB.
+ sResult = 0;
+ try {
+ hiddenOOB1(10); // no OOB
+ } catch (ArrayIndexOutOfBoundsException e) {
+ sResult += 1000;
+ }
+ expectEquals(1, sResult);
+ sResult = 0;
+ try {
+ hiddenOOB1(-2147483648); // OOB
+ } catch (ArrayIndexOutOfBoundsException e) {
+ sResult += 1000;
+ }
+ expectEquals(1001, sResult);
+ sResult = 0;
+ try {
+ hiddenOOB2(1); // no OOB
+ } catch (ArrayIndexOutOfBoundsException e) {
+ sResult += 1000;
+ }
+ expectEquals(1, sResult);
+ sResult = 0;
+ try {
+ hiddenOOB2(2147483647); // OOB
+ } catch (ArrayIndexOutOfBoundsException e) {
+ sResult += 1000;
+ }
+ expectEquals(1002, sResult);
+ sResult = 0;
+ try {
+ hiddenInfiniteOOB();
+ } catch (ArrayIndexOutOfBoundsException e) {
+ sResult += 1000;
+ }
+ expectEquals(1011, sResult);
+ sResult = 0;
+ try {
+ hiddenFiniteOOB();
+ } catch (ArrayIndexOutOfBoundsException e) {
+ sResult += 1000;
+ }
+ expectEquals(1111, sResult);
+
+ // Addition.
+ {
+ int[] e1 ={ 1, 2, 3, 4, 4, 4, 4, 3, 2, 1 };
+ int[] a1 = add();
+ for (int i = 0; i < 10; i++) {
+ expectEquals(a1[i], e1[i]);
+ }
+ }
+
// Multiplication.
{
int[] e1 = { 7, 1, 2, 2, 1, 0, 2, 0, 0, 1 };
@@ -1388,6 +1599,7 @@
expectEquals(55, dynamicBCEPossiblyInfiniteLoop(x, 0, 9));
expectEquals(55, noDynamicBCEPossiblyInfiniteLoop(x, 0, 9));
expectEquals(55, noDynamicBCEMixedInductionTypes(x, 0, 10));
+ expectEquals(125, dynamicBCEConstantRange(x));
// Dynamic BCE combined with constant indices.
int[][] a;