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[turbofan] Unify escape analysis offset calculation.

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This unifies the calculation of virtual offsets within the escape
analysis pass to go through common helpers. It also switches to safer
accessors for getting FieldAccess and ElementAccess parameters.

R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2000733002
Cr-Commit-Position: refs/heads/master@{#36423}
This commit is contained in:
mstarzinger 2016-05-20 10:51:01 -07:00 committed by Commit bot
parent ff2bd0fdcb
commit 09365ad811
2 changed files with 23 additions and 22 deletions
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44
src/compiler/escape-analysis.cc
View File

@ -1327,11 +1327,24 @@ bool EscapeAnalysis::CompareVirtualObjects(Node* left, Node* right) {
return false;
}
int EscapeAnalysis::OffsetFromAccess(Node* node) {
DCHECK(OpParameter<FieldAccess>(node).offset % kPointerSize == 0);
return OpParameter<FieldAccess>(node).offset / kPointerSize;
namespace {
int OffsetForFieldAccess(Node* node) {
FieldAccess access = FieldAccessOf(node->op());
DCHECK_EQ(access.offset % kPointerSize, 0);
return access.offset / kPointerSize;
}
int OffsetForElementAccess(Node* node, int index) {
ElementAccess access = ElementAccessOf(node->op());
DCHECK_GE(ElementSizeLog2Of(access.machine_type.representation()),
kPointerSizeLog2);
DCHECK_EQ(access.header_size % kPointerSize, 0);
return access.header_size / kPointerSize + index;
}
} // namespace
void EscapeAnalysis::ProcessLoadFromPhi(int offset, Node* from, Node* load,
VirtualState* state) {
TRACE("Load #%d from phi #%d", load->id(), from->id());
@ -1374,7 +1387,7 @@ void EscapeAnalysis::ProcessLoadField(Node* node) {
Node* from = ResolveReplacement(NodeProperties::GetValueInput(node, 0));
VirtualState* state = virtual_states_[node->id()];
if (VirtualObject* object = GetVirtualObject(state, from)) {
int offset = OffsetFromAccess(node);
int offset = OffsetForFieldAccess(node);
if (!object->IsTracked() ||
static_cast<size_t>(offset) >= object->field_count()) {
return;
@ -1386,8 +1399,8 @@ void EscapeAnalysis::ProcessLoadField(Node* node) {
// Record that the load has this alias.
UpdateReplacement(state, node, value);
} else if (from->opcode() == IrOpcode::kPhi &&
OpParameter<FieldAccess>(node).offset % kPointerSize == 0) {
int offset = OffsetFromAccess(node);
FieldAccessOf(node->op()).offset % kPointerSize == 0) {
int offset = OffsetForFieldAccess(node);
// Only binary phis are supported for now.
ProcessLoadFromPhi(offset, from, node, state);
} else {
@ -1406,19 +1419,13 @@ void EscapeAnalysis::ProcessLoadElement(Node* node) {
index_node->opcode() != IrOpcode::kInt64Constant &&
index_node->opcode() != IrOpcode::kFloat32Constant &&
index_node->opcode() != IrOpcode::kFloat64Constant);
ElementAccess access = OpParameter<ElementAccess>(node);
if (index.HasValue()) {
int offset = index.Value() + access.header_size / kPointerSize;
if (VirtualObject* object = GetVirtualObject(state, from)) {
CHECK_GE(ElementSizeLog2Of(access.machine_type.representation()),
kPointerSizeLog2);
CHECK_EQ(access.header_size % kPointerSize, 0);
int offset = OffsetForElementAccess(node, index.Value());
if (!object->IsTracked() ||
static_cast<size_t>(offset) >= object->field_count()) {
return;
}
Node* value = object->GetField(offset);
if (value) {
value = ResolveReplacement(value);
@ -1426,8 +1433,7 @@ void EscapeAnalysis::ProcessLoadElement(Node* node) {
// Record that the load has this alias.
UpdateReplacement(state, node, value);
} else if (from->opcode() == IrOpcode::kPhi) {
ElementAccess access = OpParameter<ElementAccess>(node);
int offset = index.Value() + access.header_size / kPointerSize;
int offset = OffsetForElementAccess(node, index.Value());
ProcessLoadFromPhi(offset, from, node, state);
} else {
UpdateReplacement(state, node, nullptr);
@ -1450,7 +1456,7 @@ void EscapeAnalysis::ProcessStoreField(Node* node) {
Node* to = ResolveReplacement(NodeProperties::GetValueInput(node, 0));
VirtualState* state = virtual_states_[node->id()];
VirtualObject* obj = GetVirtualObject(state, to);
int offset = OffsetFromAccess(node);
int offset = OffsetForFieldAccess(node);
if (obj && obj->IsTracked() &&
static_cast<size_t>(offset) < obj->field_count()) {
Node* val = ResolveReplacement(NodeProperties::GetValueInput(node, 1));
@ -1471,16 +1477,12 @@ void EscapeAnalysis::ProcessStoreElement(Node* node) {
index_node->opcode() != IrOpcode::kInt64Constant &&
index_node->opcode() != IrOpcode::kFloat32Constant &&
index_node->opcode() != IrOpcode::kFloat64Constant);
ElementAccess access = OpParameter<ElementAccess>(node);
VirtualState* state = virtual_states_[node->id()];
VirtualObject* obj = GetVirtualObject(state, to);
if (index.HasValue()) {
int offset = index.Value() + access.header_size / kPointerSize;
int offset = OffsetForElementAccess(node, index.Value());
if (obj && obj->IsTracked() &&
static_cast<size_t>(offset) < obj->field_count()) {
CHECK_GE(ElementSizeLog2Of(access.machine_type.representation()),
kPointerSizeLog2);
CHECK_EQ(access.header_size % kPointerSize, 0);
Node* val = ResolveReplacement(NodeProperties::GetValueInput(node, 2));
if (obj->GetField(offset) != val) {
obj = CopyForModificationAt(obj, state, node);

1
src/compiler/escape-analysis.h
View File

@ -51,7 +51,6 @@ class EscapeAnalysis {
VirtualState* states);
void ForwardVirtualState(Node* node);
int OffsetFromAccess(Node* node);
VirtualState* CopyForModificationAt(VirtualState* state, Node* node);
VirtualObject* CopyForModificationAt(VirtualObject* obj, VirtualState* state,
Node* node);