blob: 969f253ae1a513b68d996d1645be1658bcc4392d [file] [log] [blame]
// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/compiler/access-builder.h"
#include "src/compiler/graph.h"
#include "src/compiler/graph-visualizer.h"
#include "src/compiler/js-graph.h"
#include "src/compiler/loop-peeling.h"
#include "src/compiler/machine-operator.h"
#include "src/compiler/node.h"
#include "src/compiler/node-properties.h"
#include "test/unittests/compiler/compiler-test-utils.h"
#include "test/unittests/compiler/graph-unittest.h"
#include "test/unittests/compiler/node-test-utils.h"
#include "testing/gmock-support.h"
using testing::AllOf;
using testing::BitEq;
using testing::Capture;
using testing::CaptureEq;
namespace v8 {
namespace internal {
namespace compiler {
struct While {
Node* loop;
Node* branch;
Node* if_true;
Node* if_false;
Node* exit;
};
// A helper for building branches.
struct Branch {
Node* branch;
Node* if_true;
Node* if_false;
};
// A helper for building counters attached to loops.
struct Counter {
Node* base;
Node* inc;
Node* phi;
Node* add;
Node* exit_marker;
};
class LoopPeelingTest : public GraphTest {
public:
LoopPeelingTest() : GraphTest(1), machine_(zone()) {}
~LoopPeelingTest() override {}
protected:
MachineOperatorBuilder machine_;
MachineOperatorBuilder* machine() { return &machine_; }
LoopTree* GetLoopTree() {
if (FLAG_trace_turbo_graph) {
OFStream os(stdout);
os << AsRPO(*graph());
}
Zone zone(isolate()->allocator(), ZONE_NAME);
return LoopFinder::BuildLoopTree(graph(), &zone);
}
PeeledIteration* PeelOne() {
LoopTree* loop_tree = GetLoopTree();
LoopTree::Loop* loop = loop_tree->outer_loops()[0];
EXPECT_TRUE(LoopPeeler::CanPeel(loop_tree, loop));
return Peel(loop_tree, loop);
}
PeeledIteration* Peel(LoopTree* loop_tree, LoopTree::Loop* loop) {
EXPECT_TRUE(LoopPeeler::CanPeel(loop_tree, loop));
PeeledIteration* peeled =
LoopPeeler::Peel(graph(), common(), loop_tree, loop, zone());
if (FLAG_trace_turbo_graph) {
OFStream os(stdout);
os << AsRPO(*graph());
}
return peeled;
}
Node* InsertReturn(Node* val, Node* effect, Node* control) {
Node* zero = graph()->NewNode(common()->Int32Constant(0));
Node* r = graph()->NewNode(common()->Return(), zero, val, effect, control);
graph()->SetEnd(r);
return r;
}
Node* ExpectPeeled(Node* node, PeeledIteration* iter) {
Node* p = iter->map(node);
EXPECT_NE(node, p);
return p;
}
void ExpectNotPeeled(Node* node, PeeledIteration* iter) {
EXPECT_EQ(node, iter->map(node));
}
While NewWhile(Node* cond, Node* control = nullptr) {
if (control == nullptr) control = start();
While w;
w.loop = graph()->NewNode(common()->Loop(2), control, control);
w.branch = graph()->NewNode(common()->Branch(), cond, w.loop);
w.if_true = graph()->NewNode(common()->IfTrue(), w.branch);
w.if_false = graph()->NewNode(common()->IfFalse(), w.branch);
w.exit = graph()->NewNode(common()->LoopExit(), w.if_false, w.loop);
w.loop->ReplaceInput(1, w.if_true);
return w;
}
void Chain(While* a, Node* control) { a->loop->ReplaceInput(0, control); }
void Nest(While* a, While* b) {
b->loop->ReplaceInput(1, a->exit);
a->loop->ReplaceInput(0, b->if_true);
}
Node* NewPhi(While* w, Node* a, Node* b) {
return graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), a,
b, w->loop);
}
Branch NewBranch(Node* cond, Node* control = nullptr) {
Branch b;
if (control == nullptr) control = start();
b.branch = graph()->NewNode(common()->Branch(), cond, control);
b.if_true = graph()->NewNode(common()->IfTrue(), b.branch);
b.if_false = graph()->NewNode(common()->IfFalse(), b.branch);
return b;
}
Counter NewCounter(While* w, int32_t b, int32_t k) {
Counter c;
c.base = Int32Constant(b);
c.inc = Int32Constant(k);
c.phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2),
c.base, c.base, w->loop);
c.add = graph()->NewNode(machine()->Int32Add(), c.phi, c.inc);
c.phi->ReplaceInput(1, c.add);
c.exit_marker = graph()->NewNode(common()->LoopExitValue(), c.phi, w->exit);
return c;
}
};
TEST_F(LoopPeelingTest, SimpleLoop) {
Node* p0 = Parameter(0);
While w = NewWhile(p0);
Node* r = InsertReturn(p0, start(), w.exit);
PeeledIteration* peeled = PeelOne();
Node* br1 = ExpectPeeled(w.branch, peeled);
Node* if_true1 = ExpectPeeled(w.if_true, peeled);
Node* if_false1 = ExpectPeeled(w.if_false, peeled);
EXPECT_THAT(br1, IsBranch(p0, start()));
EXPECT_THAT(if_true1, IsIfTrue(br1));
EXPECT_THAT(if_false1, IsIfFalse(br1));
EXPECT_THAT(w.loop, IsLoop(if_true1, w.if_true));
EXPECT_THAT(r, IsReturn(p0, start(), IsMerge(w.if_false, if_false1)));
}
TEST_F(LoopPeelingTest, SimpleLoopWithCounter) {
Node* p0 = Parameter(0);
While w = NewWhile(p0);
Counter c = NewCounter(&w, 0, 1);
Node* r = InsertReturn(c.exit_marker, start(), w.exit);
PeeledIteration* peeled = PeelOne();
Node* br1 = ExpectPeeled(w.branch, peeled);
Node* if_true1 = ExpectPeeled(w.if_true, peeled);
Node* if_false1 = ExpectPeeled(w.if_false, peeled);
EXPECT_THAT(br1, IsBranch(p0, start()));
EXPECT_THAT(if_true1, IsIfTrue(br1));
EXPECT_THAT(if_false1, IsIfFalse(br1));
EXPECT_THAT(w.loop, IsLoop(if_true1, w.if_true));
EXPECT_THAT(peeled->map(c.add), IsInt32Add(c.base, c.inc));
EXPECT_THAT(w.exit, IsMerge(w.if_false, if_false1));
EXPECT_THAT(
r, IsReturn(IsPhi(MachineRepresentation::kTagged, c.phi, c.base, w.exit),
start(), w.exit));
}
TEST_F(LoopPeelingTest, SimpleNestedLoopWithCounter_peel_outer) {
Node* p0 = Parameter(0);
While outer = NewWhile(p0);
While inner = NewWhile(p0);
Nest(&inner, &outer);
Counter c = NewCounter(&outer, 0, 1);
Node* r = InsertReturn(c.exit_marker, start(), outer.exit);
PeeledIteration* peeled = PeelOne();
Node* bro = ExpectPeeled(outer.branch, peeled);
Node* if_trueo = ExpectPeeled(outer.if_true, peeled);
Node* if_falseo = ExpectPeeled(outer.if_false, peeled);
EXPECT_THAT(bro, IsBranch(p0, start()));
EXPECT_THAT(if_trueo, IsIfTrue(bro));
EXPECT_THAT(if_falseo, IsIfFalse(bro));
Node* bri = ExpectPeeled(inner.branch, peeled);
Node* if_truei = ExpectPeeled(inner.if_true, peeled);
Node* if_falsei = ExpectPeeled(inner.if_false, peeled);
Node* exiti = ExpectPeeled(inner.exit, peeled);
EXPECT_THAT(bri, IsBranch(p0, ExpectPeeled(inner.loop, peeled)));
EXPECT_THAT(if_truei, IsIfTrue(bri));
EXPECT_THAT(if_falsei, IsIfFalse(bri));
EXPECT_THAT(outer.loop, IsLoop(exiti, inner.exit));
EXPECT_THAT(peeled->map(c.add), IsInt32Add(c.base, c.inc));
Capture<Node*> merge;
EXPECT_THAT(outer.exit, IsMerge(outer.if_false, if_falseo));
EXPECT_THAT(r, IsReturn(IsPhi(MachineRepresentation::kTagged, c.phi, c.base,
outer.exit),
start(), outer.exit));
}
TEST_F(LoopPeelingTest, SimpleNestedLoopWithCounter_peel_inner) {
Node* p0 = Parameter(0);
While outer = NewWhile(p0);
While inner = NewWhile(p0);
Nest(&inner, &outer);
Counter c = NewCounter(&outer, 0, 1);
Node* r = InsertReturn(c.exit_marker, start(), outer.exit);
LoopTree* loop_tree = GetLoopTree();
LoopTree::Loop* loop = loop_tree->ContainingLoop(inner.loop);
EXPECT_NE(nullptr, loop);
EXPECT_EQ(1u, loop->depth());
PeeledIteration* peeled = Peel(loop_tree, loop);
ExpectNotPeeled(outer.loop, peeled);
ExpectNotPeeled(outer.branch, peeled);
ExpectNotPeeled(outer.if_true, peeled);
ExpectNotPeeled(outer.if_false, peeled);
ExpectNotPeeled(outer.exit, peeled);
Node* bri = ExpectPeeled(inner.branch, peeled);
Node* if_truei = ExpectPeeled(inner.if_true, peeled);
Node* if_falsei = ExpectPeeled(inner.if_false, peeled);
EXPECT_THAT(bri, IsBranch(p0, ExpectPeeled(inner.loop, peeled)));
EXPECT_THAT(if_truei, IsIfTrue(bri));
EXPECT_THAT(if_falsei, IsIfFalse(bri));
EXPECT_THAT(inner.exit, IsMerge(inner.if_false, if_falsei));
EXPECT_THAT(outer.loop, IsLoop(start(), inner.exit));
ExpectNotPeeled(c.add, peeled);
EXPECT_THAT(r, IsReturn(c.exit_marker, start(), outer.exit));
}
TEST_F(LoopPeelingTest, SimpleInnerCounter_peel_inner) {
Node* p0 = Parameter(0);
While outer = NewWhile(p0);
While inner = NewWhile(p0);
Nest(&inner, &outer);
Counter c = NewCounter(&inner, 0, 1);
Node* phi = NewPhi(&outer, Int32Constant(11), c.exit_marker);
Node* r = InsertReturn(phi, start(), outer.exit);
LoopTree* loop_tree = GetLoopTree();
LoopTree::Loop* loop = loop_tree->ContainingLoop(inner.loop);
EXPECT_NE(nullptr, loop);
EXPECT_EQ(1u, loop->depth());
PeeledIteration* peeled = Peel(loop_tree, loop);
ExpectNotPeeled(outer.loop, peeled);
ExpectNotPeeled(outer.branch, peeled);
ExpectNotPeeled(outer.if_true, peeled);
ExpectNotPeeled(outer.if_false, peeled);
ExpectNotPeeled(outer.exit, peeled);
Node* bri = ExpectPeeled(inner.branch, peeled);
Node* if_truei = ExpectPeeled(inner.if_true, peeled);
Node* if_falsei = ExpectPeeled(inner.if_false, peeled);
EXPECT_THAT(bri, IsBranch(p0, ExpectPeeled(inner.loop, peeled)));
EXPECT_THAT(if_truei, IsIfTrue(bri));
EXPECT_THAT(if_falsei, IsIfFalse(bri));
EXPECT_THAT(inner.exit, IsMerge(inner.if_false, if_falsei));
EXPECT_THAT(outer.loop, IsLoop(start(), inner.exit));
EXPECT_THAT(peeled->map(c.add), IsInt32Add(c.base, c.inc));
EXPECT_THAT(c.exit_marker,
IsPhi(MachineRepresentation::kTagged, c.phi, c.base, inner.exit));
EXPECT_THAT(phi, IsPhi(MachineRepresentation::kTagged, IsInt32Constant(11),
c.exit_marker, outer.loop));
EXPECT_THAT(r, IsReturn(phi, start(), outer.exit));
}
TEST_F(LoopPeelingTest, TwoBackedgeLoop) {
Node* p0 = Parameter(0);
Node* loop = graph()->NewNode(common()->Loop(3), start(), start(), start());
Branch b1 = NewBranch(p0, loop);
Branch b2 = NewBranch(p0, b1.if_true);
loop->ReplaceInput(1, b2.if_true);
loop->ReplaceInput(2, b2.if_false);
Node* exit = graph()->NewNode(common()->LoopExit(), b1.if_false, loop);
Node* r = InsertReturn(p0, start(), exit);
PeeledIteration* peeled = PeelOne();
Node* b1b = ExpectPeeled(b1.branch, peeled);
Node* b1t = ExpectPeeled(b1.if_true, peeled);
Node* b1f = ExpectPeeled(b1.if_false, peeled);
EXPECT_THAT(b1b, IsBranch(p0, start()));
EXPECT_THAT(ExpectPeeled(b1.if_true, peeled), IsIfTrue(b1b));
EXPECT_THAT(b1f, IsIfFalse(b1b));
Node* b2b = ExpectPeeled(b2.branch, peeled);
Node* b2t = ExpectPeeled(b2.if_true, peeled);
Node* b2f = ExpectPeeled(b2.if_false, peeled);
EXPECT_THAT(b2b, IsBranch(p0, b1t));
EXPECT_THAT(b2t, IsIfTrue(b2b));
EXPECT_THAT(b2f, IsIfFalse(b2b));
EXPECT_THAT(loop, IsLoop(IsMerge(b2t, b2f), b2.if_true, b2.if_false));
EXPECT_THAT(exit, IsMerge(b1.if_false, b1f));
EXPECT_THAT(r, IsReturn(p0, start(), exit));
}
TEST_F(LoopPeelingTest, TwoBackedgeLoopWithPhi) {
Node* p0 = Parameter(0);
Node* loop = graph()->NewNode(common()->Loop(3), start(), start(), start());
Branch b1 = NewBranch(p0, loop);
Branch b2 = NewBranch(p0, b1.if_true);
Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 3),
Int32Constant(0), Int32Constant(1),
Int32Constant(2), loop);
loop->ReplaceInput(1, b2.if_true);
loop->ReplaceInput(2, b2.if_false);
Node* exit = graph()->NewNode(common()->LoopExit(), b1.if_false, loop);
Node* exit_marker = graph()->NewNode(common()->LoopExitValue(), phi, exit);
Node* r = InsertReturn(exit_marker, start(), exit);
PeeledIteration* peeled = PeelOne();
Node* b1b = ExpectPeeled(b1.branch, peeled);
Node* b1t = ExpectPeeled(b1.if_true, peeled);
Node* b1f = ExpectPeeled(b1.if_false, peeled);
EXPECT_THAT(b1b, IsBranch(p0, start()));
EXPECT_THAT(ExpectPeeled(b1.if_true, peeled), IsIfTrue(b1b));
EXPECT_THAT(b1f, IsIfFalse(b1b));
Node* b2b = ExpectPeeled(b2.branch, peeled);
Node* b2t = ExpectPeeled(b2.if_true, peeled);
Node* b2f = ExpectPeeled(b2.if_false, peeled);
EXPECT_THAT(b2b, IsBranch(p0, b1t));
EXPECT_THAT(b2t, IsIfTrue(b2b));
EXPECT_THAT(b2f, IsIfFalse(b2b));
EXPECT_THAT(loop, IsLoop(IsMerge(b2t, b2f), b2.if_true, b2.if_false));
EXPECT_THAT(phi,
IsPhi(MachineRepresentation::kTagged,
IsPhi(MachineRepresentation::kTagged, IsInt32Constant(1),
IsInt32Constant(2), IsMerge(b2t, b2f)),
IsInt32Constant(1), IsInt32Constant(2), loop));
EXPECT_THAT(exit, IsMerge(b1.if_false, b1f));
EXPECT_THAT(exit_marker, IsPhi(MachineRepresentation::kTagged, phi,
IsInt32Constant(0), exit));
EXPECT_THAT(r, IsReturn(exit_marker, start(), exit));
}
TEST_F(LoopPeelingTest, TwoBackedgeLoopWithCounter) {
Node* p0 = Parameter(0);
Node* loop = graph()->NewNode(common()->Loop(3), start(), start(), start());
Branch b1 = NewBranch(p0, loop);
Branch b2 = NewBranch(p0, b1.if_true);
Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 3),
Int32Constant(0), Int32Constant(1),
Int32Constant(2), loop);
phi->ReplaceInput(
1, graph()->NewNode(machine()->Int32Add(), phi, Int32Constant(1)));
phi->ReplaceInput(
2, graph()->NewNode(machine()->Int32Add(), phi, Int32Constant(2)));
loop->ReplaceInput(1, b2.if_true);
loop->ReplaceInput(2, b2.if_false);
Node* exit = graph()->NewNode(common()->LoopExit(), b1.if_false, loop);
Node* exit_marker = graph()->NewNode(common()->LoopExitValue(), phi, exit);
Node* r = InsertReturn(exit_marker, start(), exit);
PeeledIteration* peeled = PeelOne();
Node* b1b = ExpectPeeled(b1.branch, peeled);
Node* b1t = ExpectPeeled(b1.if_true, peeled);
Node* b1f = ExpectPeeled(b1.if_false, peeled);
EXPECT_THAT(b1b, IsBranch(p0, start()));
EXPECT_THAT(ExpectPeeled(b1.if_true, peeled), IsIfTrue(b1b));
EXPECT_THAT(b1f, IsIfFalse(b1b));
Node* b2b = ExpectPeeled(b2.branch, peeled);
Node* b2t = ExpectPeeled(b2.if_true, peeled);
Node* b2f = ExpectPeeled(b2.if_false, peeled);
EXPECT_THAT(b2b, IsBranch(p0, b1t));
EXPECT_THAT(b2t, IsIfTrue(b2b));
EXPECT_THAT(b2f, IsIfFalse(b2b));
Capture<Node*> entry;
EXPECT_THAT(loop, IsLoop(AllOf(CaptureEq(&entry), IsMerge(b2t, b2f)),
b2.if_true, b2.if_false));
Node* eval = phi->InputAt(0);
EXPECT_THAT(eval, IsPhi(MachineRepresentation::kTagged,
IsInt32Add(IsInt32Constant(0), IsInt32Constant(1)),
IsInt32Add(IsInt32Constant(0), IsInt32Constant(2)),
CaptureEq(&entry)));
EXPECT_THAT(phi, IsPhi(MachineRepresentation::kTagged, eval,
IsInt32Add(phi, IsInt32Constant(1)),
IsInt32Add(phi, IsInt32Constant(2)), loop));
EXPECT_THAT(exit, IsMerge(b1.if_false, b1f));
EXPECT_THAT(exit_marker, IsPhi(MachineRepresentation::kTagged, phi,
IsInt32Constant(0), exit));
EXPECT_THAT(r, IsReturn(exit_marker, start(), exit));
}
TEST_F(LoopPeelingTest, TwoExitLoop) {
Node* p0 = Parameter(0);
Node* loop = graph()->NewNode(common()->Loop(2), start(), start());
Branch b1 = NewBranch(p0, loop);
Branch b2 = NewBranch(p0, b1.if_true);
loop->ReplaceInput(1, b2.if_true);
Node* exit1 = graph()->NewNode(common()->LoopExit(), b1.if_false, loop);
Node* exit2 = graph()->NewNode(common()->LoopExit(), b2.if_false, loop);
Node* merge = graph()->NewNode(common()->Merge(2), exit1, exit2);
Node* r = InsertReturn(p0, start(), merge);
PeeledIteration* peeled = PeelOne();
Node* b1p = ExpectPeeled(b1.branch, peeled);
Node* if_true1p = ExpectPeeled(b1.if_true, peeled);
Node* if_false1p = ExpectPeeled(b1.if_false, peeled);
Node* b2p = ExpectPeeled(b2.branch, peeled);
Node* if_true2p = ExpectPeeled(b2.if_true, peeled);
Node* if_false2p = ExpectPeeled(b2.if_false, peeled);
EXPECT_THAT(b1p, IsBranch(p0, start()));
EXPECT_THAT(if_true1p, IsIfTrue(b1p));
EXPECT_THAT(if_false1p, IsIfFalse(b1p));
EXPECT_THAT(b2p, IsBranch(p0, if_true1p));
EXPECT_THAT(if_true2p, IsIfTrue(b2p));
EXPECT_THAT(if_false2p, IsIfFalse(b2p));
EXPECT_THAT(exit1, IsMerge(b1.if_false, if_false1p));
EXPECT_THAT(exit2, IsMerge(b2.if_false, if_false2p));
EXPECT_THAT(loop, IsLoop(if_true2p, b2.if_true));
EXPECT_THAT(merge, IsMerge(exit1, exit2));
EXPECT_THAT(r, IsReturn(p0, start(), merge));
}
TEST_F(LoopPeelingTest, SimpleLoopWithUnmarkedExit) {
Node* p0 = Parameter(0);
Node* loop = graph()->NewNode(common()->Loop(2), start(), start());
Branch b = NewBranch(p0, loop);
loop->ReplaceInput(1, b.if_true);
InsertReturn(p0, start(), b.if_false);
{
LoopTree* loop_tree = GetLoopTree();
LoopTree::Loop* loop = loop_tree->outer_loops()[0];
EXPECT_FALSE(LoopPeeler::CanPeel(loop_tree, loop));
}
}
} // namespace compiler
} // namespace internal
} // namespace v8