Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1 | // Copyright 2014 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "src/compiler/access-builder.h" |
| 6 | #include "src/compiler/graph-inl.h" |
| 7 | #include "src/compiler/js-builtin-reducer.h" |
| 8 | #include "src/compiler/js-typed-lowering.h" |
| 9 | #include "src/compiler/node-aux-data-inl.h" |
| 10 | #include "src/compiler/node-properties-inl.h" |
| 11 | #include "src/types.h" |
| 12 | |
| 13 | namespace v8 { |
| 14 | namespace internal { |
| 15 | namespace compiler { |
| 16 | |
| 17 | // TODO(turbofan): js-typed-lowering improvements possible |
| 18 | // - immediately put in type bounds for all new nodes |
| 19 | // - relax effects from generic but not-side-effecting operations |
| 20 | // - relax effects for ToNumber(mixed) |
| 21 | |
| 22 | |
| 23 | // Relax the effects of {node} by immediately replacing effect uses of {node} |
| 24 | // with the effect input to {node}. |
| 25 | // TODO(turbofan): replace the effect input to {node} with {graph->start()}. |
| 26 | // TODO(titzer): move into a GraphEditor? |
| 27 | static void RelaxEffects(Node* node) { |
| 28 | NodeProperties::ReplaceWithValue(node, node, NULL); |
| 29 | } |
| 30 | |
| 31 | |
| 32 | JSTypedLowering::~JSTypedLowering() {} |
| 33 | |
| 34 | |
| 35 | Reduction JSTypedLowering::ReplaceEagerly(Node* old, Node* node) { |
| 36 | NodeProperties::ReplaceWithValue(old, node, node); |
| 37 | return Changed(node); |
| 38 | } |
| 39 | |
| 40 | |
| 41 | // A helper class to simplify the process of reducing a single binop node with a |
| 42 | // JSOperator. This class manages the rewriting of context, control, and effect |
| 43 | // dependencies during lowering of a binop and contains numerous helper |
| 44 | // functions for matching the types of inputs to an operation. |
| 45 | class JSBinopReduction { |
| 46 | public: |
| 47 | JSBinopReduction(JSTypedLowering* lowering, Node* node) |
| 48 | : lowering_(lowering), |
| 49 | node_(node), |
| 50 | left_type_(NodeProperties::GetBounds(node->InputAt(0)).upper), |
| 51 | right_type_(NodeProperties::GetBounds(node->InputAt(1)).upper) {} |
| 52 | |
| 53 | void ConvertInputsToNumber() { |
| 54 | node_->ReplaceInput(0, ConvertToNumber(left())); |
| 55 | node_->ReplaceInput(1, ConvertToNumber(right())); |
| 56 | } |
| 57 | |
| 58 | void ConvertInputsToInt32(bool left_signed, bool right_signed) { |
| 59 | node_->ReplaceInput(0, ConvertToI32(left_signed, left())); |
| 60 | node_->ReplaceInput(1, ConvertToI32(right_signed, right())); |
| 61 | } |
| 62 | |
| 63 | void ConvertInputsToString() { |
| 64 | node_->ReplaceInput(0, ConvertToString(left())); |
| 65 | node_->ReplaceInput(1, ConvertToString(right())); |
| 66 | } |
| 67 | |
| 68 | // Convert inputs for bitwise shift operation (ES5 spec 11.7). |
| 69 | void ConvertInputsForShift(bool left_signed) { |
| 70 | node_->ReplaceInput(0, ConvertToI32(left_signed, left())); |
| 71 | Node* rnum = ConvertToI32(false, right()); |
| 72 | node_->ReplaceInput(1, graph()->NewNode(machine()->Word32And(), rnum, |
| 73 | jsgraph()->Int32Constant(0x1F))); |
| 74 | } |
| 75 | |
| 76 | void SwapInputs() { |
| 77 | Node* l = left(); |
| 78 | Node* r = right(); |
| 79 | node_->ReplaceInput(0, r); |
| 80 | node_->ReplaceInput(1, l); |
| 81 | std::swap(left_type_, right_type_); |
| 82 | } |
| 83 | |
| 84 | // Remove all effect and control inputs and outputs to this node and change |
| 85 | // to the pure operator {op}, possibly inserting a boolean inversion. |
| 86 | Reduction ChangeToPureOperator(const Operator* op, bool invert = false) { |
| 87 | DCHECK_EQ(0, OperatorProperties::GetEffectInputCount(op)); |
| 88 | DCHECK_EQ(false, OperatorProperties::HasContextInput(op)); |
| 89 | DCHECK_EQ(0, OperatorProperties::GetControlInputCount(op)); |
| 90 | DCHECK_EQ(2, OperatorProperties::GetValueInputCount(op)); |
| 91 | |
| 92 | // Remove the effects from the node, if any, and update its effect usages. |
| 93 | if (OperatorProperties::GetEffectInputCount(node_->op()) > 0) { |
| 94 | RelaxEffects(node_); |
| 95 | } |
| 96 | // Remove the inputs corresponding to context, effect, and control. |
| 97 | NodeProperties::RemoveNonValueInputs(node_); |
| 98 | // Finally, update the operator to the new one. |
| 99 | node_->set_op(op); |
| 100 | |
| 101 | if (invert) { |
| 102 | // Insert an boolean not to invert the value. |
| 103 | Node* value = graph()->NewNode(simplified()->BooleanNot(), node_); |
| 104 | node_->ReplaceUses(value); |
| 105 | // Note: ReplaceUses() smashes all uses, so smash it back here. |
| 106 | value->ReplaceInput(0, node_); |
| 107 | return lowering_->ReplaceWith(value); |
| 108 | } |
| 109 | return lowering_->Changed(node_); |
| 110 | } |
| 111 | |
| 112 | bool OneInputIs(Type* t) { return left_type_->Is(t) || right_type_->Is(t); } |
| 113 | |
| 114 | bool BothInputsAre(Type* t) { |
| 115 | return left_type_->Is(t) && right_type_->Is(t); |
| 116 | } |
| 117 | |
| 118 | bool OneInputCannotBe(Type* t) { |
| 119 | return !left_type_->Maybe(t) || !right_type_->Maybe(t); |
| 120 | } |
| 121 | |
| 122 | bool NeitherInputCanBe(Type* t) { |
| 123 | return !left_type_->Maybe(t) && !right_type_->Maybe(t); |
| 124 | } |
| 125 | |
| 126 | Node* effect() { return NodeProperties::GetEffectInput(node_); } |
| 127 | Node* control() { return NodeProperties::GetControlInput(node_); } |
| 128 | Node* context() { return NodeProperties::GetContextInput(node_); } |
| 129 | Node* left() { return NodeProperties::GetValueInput(node_, 0); } |
| 130 | Node* right() { return NodeProperties::GetValueInput(node_, 1); } |
| 131 | Type* left_type() { return left_type_; } |
| 132 | Type* right_type() { return right_type_; } |
| 133 | |
| 134 | SimplifiedOperatorBuilder* simplified() { return lowering_->simplified(); } |
| 135 | Graph* graph() { return lowering_->graph(); } |
| 136 | JSGraph* jsgraph() { return lowering_->jsgraph(); } |
| 137 | JSOperatorBuilder* javascript() { return lowering_->javascript(); } |
| 138 | MachineOperatorBuilder* machine() { return lowering_->machine(); } |
| 139 | |
| 140 | private: |
| 141 | JSTypedLowering* lowering_; // The containing lowering instance. |
| 142 | Node* node_; // The original node. |
| 143 | Type* left_type_; // Cache of the left input's type. |
| 144 | Type* right_type_; // Cache of the right input's type. |
| 145 | |
| 146 | Node* ConvertToString(Node* node) { |
| 147 | // Avoid introducing too many eager ToString() operations. |
| 148 | Reduction reduced = lowering_->ReduceJSToStringInput(node); |
| 149 | if (reduced.Changed()) return reduced.replacement(); |
| 150 | Node* n = graph()->NewNode(javascript()->ToString(), node, context(), |
| 151 | effect(), control()); |
| 152 | update_effect(n); |
| 153 | return n; |
| 154 | } |
| 155 | |
| 156 | Node* ConvertToNumber(Node* node) { |
| 157 | // Avoid introducing too many eager ToNumber() operations. |
| 158 | Reduction reduced = lowering_->ReduceJSToNumberInput(node); |
| 159 | if (reduced.Changed()) return reduced.replacement(); |
| 160 | Node* n = graph()->NewNode(javascript()->ToNumber(), node, context(), |
| 161 | effect(), control()); |
| 162 | update_effect(n); |
| 163 | return n; |
| 164 | } |
| 165 | |
| 166 | // Try to narrowing a double or number operation to an Int32 operation. |
| 167 | bool TryNarrowingToI32(Type* type, Node* node) { |
| 168 | switch (node->opcode()) { |
| 169 | case IrOpcode::kFloat64Add: |
| 170 | case IrOpcode::kNumberAdd: { |
| 171 | JSBinopReduction r(lowering_, node); |
| 172 | if (r.BothInputsAre(Type::Integral32())) { |
| 173 | node->set_op(lowering_->machine()->Int32Add()); |
| 174 | // TODO(titzer): narrow bounds instead of overwriting. |
| 175 | NodeProperties::SetBounds(node, Bounds(type)); |
| 176 | return true; |
| 177 | } |
| 178 | } |
| 179 | case IrOpcode::kFloat64Sub: |
| 180 | case IrOpcode::kNumberSubtract: { |
| 181 | JSBinopReduction r(lowering_, node); |
| 182 | if (r.BothInputsAre(Type::Integral32())) { |
| 183 | node->set_op(lowering_->machine()->Int32Sub()); |
| 184 | // TODO(titzer): narrow bounds instead of overwriting. |
| 185 | NodeProperties::SetBounds(node, Bounds(type)); |
| 186 | return true; |
| 187 | } |
| 188 | } |
| 189 | default: |
| 190 | return false; |
| 191 | } |
| 192 | } |
| 193 | |
| 194 | Node* ConvertToI32(bool is_signed, Node* node) { |
| 195 | Type* type = is_signed ? Type::Signed32() : Type::Unsigned32(); |
| 196 | if (node->OwnedBy(node_)) { |
| 197 | // If this node {node_} has the only edge to {node}, then try narrowing |
| 198 | // its operation to an Int32 add or subtract. |
| 199 | if (TryNarrowingToI32(type, node)) return node; |
| 200 | } else { |
| 201 | // Otherwise, {node} has multiple uses. Leave it as is and let the |
| 202 | // further lowering passes deal with it, which use a full backwards |
| 203 | // fixpoint. |
| 204 | } |
| 205 | |
| 206 | // Avoid introducing too many eager NumberToXXnt32() operations. |
| 207 | node = ConvertToNumber(node); |
| 208 | Type* input_type = NodeProperties::GetBounds(node).upper; |
| 209 | |
| 210 | if (input_type->Is(type)) return node; // already in the value range. |
| 211 | |
| 212 | const Operator* op = is_signed ? simplified()->NumberToInt32() |
| 213 | : simplified()->NumberToUint32(); |
| 214 | Node* n = graph()->NewNode(op, node); |
| 215 | return n; |
| 216 | } |
| 217 | |
| 218 | void update_effect(Node* effect) { |
| 219 | NodeProperties::ReplaceEffectInput(node_, effect); |
| 220 | } |
| 221 | }; |
| 222 | |
| 223 | |
| 224 | Reduction JSTypedLowering::ReduceJSAdd(Node* node) { |
| 225 | JSBinopReduction r(this, node); |
| 226 | if (r.BothInputsAre(Type::Number())) { |
| 227 | // JSAdd(x:number, y:number) => NumberAdd(x, y) |
| 228 | return r.ChangeToPureOperator(simplified()->NumberAdd()); |
| 229 | } |
| 230 | Type* maybe_string = Type::Union(Type::String(), Type::Receiver(), zone()); |
| 231 | if (r.NeitherInputCanBe(maybe_string)) { |
| 232 | // JSAdd(x:-string, y:-string) => NumberAdd(ToNumber(x), ToNumber(y)) |
| 233 | r.ConvertInputsToNumber(); |
| 234 | return r.ChangeToPureOperator(simplified()->NumberAdd()); |
| 235 | } |
| 236 | #if 0 |
| 237 | // TODO(turbofan): Lowering of StringAdd is disabled for now because: |
| 238 | // a) The inserted ToString operation screws up valueOf vs. toString order. |
| 239 | // b) Deoptimization at ToString doesn't have corresponding bailout id. |
| 240 | // c) Our current StringAddStub is actually non-pure and requires context. |
| 241 | if (r.OneInputIs(Type::String())) { |
| 242 | // JSAdd(x:string, y:string) => StringAdd(x, y) |
| 243 | // JSAdd(x:string, y) => StringAdd(x, ToString(y)) |
| 244 | // JSAdd(x, y:string) => StringAdd(ToString(x), y) |
| 245 | r.ConvertInputsToString(); |
| 246 | return r.ChangeToPureOperator(simplified()->StringAdd()); |
| 247 | } |
| 248 | #endif |
| 249 | return NoChange(); |
| 250 | } |
| 251 | |
| 252 | |
| 253 | Reduction JSTypedLowering::ReduceNumberBinop(Node* node, |
| 254 | const Operator* numberOp) { |
| 255 | JSBinopReduction r(this, node); |
| 256 | if (r.OneInputIs(Type::Primitive())) { |
| 257 | // If at least one input is a primitive, then insert appropriate conversions |
| 258 | // to number and reduce this operator to the given numeric one. |
| 259 | // TODO(turbofan): make this heuristic configurable for code size. |
| 260 | r.ConvertInputsToNumber(); |
| 261 | return r.ChangeToPureOperator(numberOp); |
| 262 | } |
| 263 | // TODO(turbofan): relax/remove the effects of this operator in other cases. |
| 264 | return NoChange(); |
| 265 | } |
| 266 | |
| 267 | |
| 268 | Reduction JSTypedLowering::ReduceI32Binop(Node* node, bool left_signed, |
| 269 | bool right_signed, |
| 270 | const Operator* intOp) { |
| 271 | JSBinopReduction r(this, node); |
| 272 | // TODO(titzer): some Smi bitwise operations don't really require going |
| 273 | // all the way to int32, which can save tagging/untagging for some operations |
| 274 | // on some platforms. |
| 275 | // TODO(turbofan): make this heuristic configurable for code size. |
| 276 | r.ConvertInputsToInt32(left_signed, right_signed); |
| 277 | return r.ChangeToPureOperator(intOp); |
| 278 | } |
| 279 | |
| 280 | |
| 281 | Reduction JSTypedLowering::ReduceI32Shift(Node* node, bool left_signed, |
| 282 | const Operator* shift_op) { |
| 283 | JSBinopReduction r(this, node); |
| 284 | r.ConvertInputsForShift(left_signed); |
| 285 | return r.ChangeToPureOperator(shift_op); |
| 286 | } |
| 287 | |
| 288 | |
| 289 | Reduction JSTypedLowering::ReduceJSComparison(Node* node) { |
| 290 | JSBinopReduction r(this, node); |
| 291 | if (r.BothInputsAre(Type::String())) { |
| 292 | // If both inputs are definitely strings, perform a string comparison. |
| 293 | const Operator* stringOp; |
| 294 | switch (node->opcode()) { |
| 295 | case IrOpcode::kJSLessThan: |
| 296 | stringOp = simplified()->StringLessThan(); |
| 297 | break; |
| 298 | case IrOpcode::kJSGreaterThan: |
| 299 | stringOp = simplified()->StringLessThan(); |
| 300 | r.SwapInputs(); // a > b => b < a |
| 301 | break; |
| 302 | case IrOpcode::kJSLessThanOrEqual: |
| 303 | stringOp = simplified()->StringLessThanOrEqual(); |
| 304 | break; |
| 305 | case IrOpcode::kJSGreaterThanOrEqual: |
| 306 | stringOp = simplified()->StringLessThanOrEqual(); |
| 307 | r.SwapInputs(); // a >= b => b <= a |
| 308 | break; |
| 309 | default: |
| 310 | return NoChange(); |
| 311 | } |
| 312 | return r.ChangeToPureOperator(stringOp); |
| 313 | } |
| 314 | Type* maybe_string = Type::Union(Type::String(), Type::Receiver(), zone()); |
| 315 | if (r.OneInputCannotBe(maybe_string)) { |
| 316 | // If one input cannot be a string, then emit a number comparison. |
| 317 | const Operator* less_than; |
| 318 | const Operator* less_than_or_equal; |
| 319 | if (r.BothInputsAre(Type::Unsigned32())) { |
| 320 | less_than = machine()->Uint32LessThan(); |
| 321 | less_than_or_equal = machine()->Uint32LessThanOrEqual(); |
| 322 | } else if (r.BothInputsAre(Type::Signed32())) { |
| 323 | less_than = machine()->Int32LessThan(); |
| 324 | less_than_or_equal = machine()->Int32LessThanOrEqual(); |
| 325 | } else { |
| 326 | // TODO(turbofan): mixed signed/unsigned int32 comparisons. |
| 327 | r.ConvertInputsToNumber(); |
| 328 | less_than = simplified()->NumberLessThan(); |
| 329 | less_than_or_equal = simplified()->NumberLessThanOrEqual(); |
| 330 | } |
| 331 | const Operator* comparison; |
| 332 | switch (node->opcode()) { |
| 333 | case IrOpcode::kJSLessThan: |
| 334 | comparison = less_than; |
| 335 | break; |
| 336 | case IrOpcode::kJSGreaterThan: |
| 337 | comparison = less_than; |
| 338 | r.SwapInputs(); // a > b => b < a |
| 339 | break; |
| 340 | case IrOpcode::kJSLessThanOrEqual: |
| 341 | comparison = less_than_or_equal; |
| 342 | break; |
| 343 | case IrOpcode::kJSGreaterThanOrEqual: |
| 344 | comparison = less_than_or_equal; |
| 345 | r.SwapInputs(); // a >= b => b <= a |
| 346 | break; |
| 347 | default: |
| 348 | return NoChange(); |
| 349 | } |
| 350 | return r.ChangeToPureOperator(comparison); |
| 351 | } |
| 352 | // TODO(turbofan): relax/remove effects of this operator in other cases. |
| 353 | return NoChange(); // Keep a generic comparison. |
| 354 | } |
| 355 | |
| 356 | |
| 357 | Reduction JSTypedLowering::ReduceJSEqual(Node* node, bool invert) { |
| 358 | JSBinopReduction r(this, node); |
| 359 | |
| 360 | if (r.BothInputsAre(Type::Number())) { |
| 361 | return r.ChangeToPureOperator(simplified()->NumberEqual(), invert); |
| 362 | } |
| 363 | if (r.BothInputsAre(Type::String())) { |
| 364 | return r.ChangeToPureOperator(simplified()->StringEqual(), invert); |
| 365 | } |
| 366 | if (r.BothInputsAre(Type::Receiver())) { |
| 367 | return r.ChangeToPureOperator( |
| 368 | simplified()->ReferenceEqual(Type::Receiver()), invert); |
| 369 | } |
| 370 | // TODO(turbofan): js-typed-lowering of Equal(undefined) |
| 371 | // TODO(turbofan): js-typed-lowering of Equal(null) |
| 372 | // TODO(turbofan): js-typed-lowering of Equal(boolean) |
| 373 | return NoChange(); |
| 374 | } |
| 375 | |
| 376 | |
| 377 | Reduction JSTypedLowering::ReduceJSStrictEqual(Node* node, bool invert) { |
| 378 | JSBinopReduction r(this, node); |
| 379 | if (r.left() == r.right()) { |
| 380 | // x === x is always true if x != NaN |
| 381 | if (!r.left_type()->Maybe(Type::NaN())) { |
| 382 | return ReplaceEagerly(node, invert ? jsgraph()->FalseConstant() |
| 383 | : jsgraph()->TrueConstant()); |
| 384 | } |
| 385 | } |
| 386 | if (!r.left_type()->Maybe(r.right_type())) { |
| 387 | // Type intersection is empty; === is always false unless both |
| 388 | // inputs could be strings (one internalized and one not). |
| 389 | if (r.OneInputCannotBe(Type::String())) { |
| 390 | return ReplaceEagerly(node, invert ? jsgraph()->TrueConstant() |
| 391 | : jsgraph()->FalseConstant()); |
| 392 | } |
| 393 | } |
| 394 | if (r.OneInputIs(Type::Undefined())) { |
| 395 | return r.ChangeToPureOperator( |
| 396 | simplified()->ReferenceEqual(Type::Undefined()), invert); |
| 397 | } |
| 398 | if (r.OneInputIs(Type::Null())) { |
| 399 | return r.ChangeToPureOperator(simplified()->ReferenceEqual(Type::Null()), |
| 400 | invert); |
| 401 | } |
| 402 | if (r.OneInputIs(Type::Boolean())) { |
| 403 | return r.ChangeToPureOperator(simplified()->ReferenceEqual(Type::Boolean()), |
| 404 | invert); |
| 405 | } |
| 406 | if (r.OneInputIs(Type::Object())) { |
| 407 | return r.ChangeToPureOperator(simplified()->ReferenceEqual(Type::Object()), |
| 408 | invert); |
| 409 | } |
| 410 | if (r.OneInputIs(Type::Receiver())) { |
| 411 | return r.ChangeToPureOperator( |
| 412 | simplified()->ReferenceEqual(Type::Receiver()), invert); |
| 413 | } |
| 414 | if (r.BothInputsAre(Type::String())) { |
| 415 | return r.ChangeToPureOperator(simplified()->StringEqual(), invert); |
| 416 | } |
| 417 | if (r.BothInputsAre(Type::Number())) { |
| 418 | return r.ChangeToPureOperator(simplified()->NumberEqual(), invert); |
| 419 | } |
| 420 | // TODO(turbofan): js-typed-lowering of StrictEqual(mixed types) |
| 421 | return NoChange(); |
| 422 | } |
| 423 | |
| 424 | |
| 425 | Reduction JSTypedLowering::ReduceJSToNumberInput(Node* input) { |
| 426 | if (input->opcode() == IrOpcode::kJSToNumber) { |
| 427 | // Recursively try to reduce the input first. |
| 428 | Reduction result = ReduceJSToNumberInput(input->InputAt(0)); |
| 429 | if (result.Changed()) { |
| 430 | RelaxEffects(input); |
| 431 | return result; |
| 432 | } |
| 433 | return Changed(input); // JSToNumber(JSToNumber(x)) => JSToNumber(x) |
| 434 | } |
| 435 | Type* input_type = NodeProperties::GetBounds(input).upper; |
| 436 | if (input_type->Is(Type::Number())) { |
| 437 | // JSToNumber(x:number) => x |
| 438 | return Changed(input); |
| 439 | } |
| 440 | if (input_type->Is(Type::Undefined())) { |
| 441 | // JSToNumber(undefined) => #NaN |
| 442 | return ReplaceWith(jsgraph()->NaNConstant()); |
| 443 | } |
| 444 | if (input_type->Is(Type::Null())) { |
| 445 | // JSToNumber(null) => #0 |
| 446 | return ReplaceWith(jsgraph()->ZeroConstant()); |
| 447 | } |
| 448 | if (input_type->Is(Type::Boolean())) { |
| 449 | // JSToNumber(x:boolean) => BooleanToNumber(x) |
| 450 | return ReplaceWith( |
| 451 | graph()->NewNode(simplified()->BooleanToNumber(), input)); |
| 452 | } |
| 453 | // TODO(turbofan): js-typed-lowering of ToNumber(x:string) |
| 454 | return NoChange(); |
| 455 | } |
| 456 | |
| 457 | |
| 458 | Reduction JSTypedLowering::ReduceJSToStringInput(Node* input) { |
| 459 | if (input->opcode() == IrOpcode::kJSToString) { |
| 460 | // Recursively try to reduce the input first. |
| 461 | Reduction result = ReduceJSToStringInput(input->InputAt(0)); |
| 462 | if (result.Changed()) { |
| 463 | RelaxEffects(input); |
| 464 | return result; |
| 465 | } |
| 466 | return Changed(input); // JSToString(JSToString(x)) => JSToString(x) |
| 467 | } |
| 468 | Type* input_type = NodeProperties::GetBounds(input).upper; |
| 469 | if (input_type->Is(Type::String())) { |
| 470 | return Changed(input); // JSToString(x:string) => x |
| 471 | } |
| 472 | if (input_type->Is(Type::Undefined())) { |
| 473 | return ReplaceWith(jsgraph()->HeapConstant( |
| 474 | graph()->zone()->isolate()->factory()->undefined_string())); |
| 475 | } |
| 476 | if (input_type->Is(Type::Null())) { |
| 477 | return ReplaceWith(jsgraph()->HeapConstant( |
| 478 | graph()->zone()->isolate()->factory()->null_string())); |
| 479 | } |
| 480 | // TODO(turbofan): js-typed-lowering of ToString(x:boolean) |
| 481 | // TODO(turbofan): js-typed-lowering of ToString(x:number) |
| 482 | return NoChange(); |
| 483 | } |
| 484 | |
| 485 | |
| 486 | Reduction JSTypedLowering::ReduceJSToBooleanInput(Node* input) { |
| 487 | if (input->opcode() == IrOpcode::kJSToBoolean) { |
| 488 | // Recursively try to reduce the input first. |
| 489 | Reduction result = ReduceJSToBooleanInput(input->InputAt(0)); |
| 490 | if (result.Changed()) { |
| 491 | RelaxEffects(input); |
| 492 | return result; |
| 493 | } |
| 494 | return Changed(input); // JSToBoolean(JSToBoolean(x)) => JSToBoolean(x) |
| 495 | } |
| 496 | Type* input_type = NodeProperties::GetBounds(input).upper; |
| 497 | if (input_type->Is(Type::Boolean())) { |
| 498 | return Changed(input); // JSToBoolean(x:boolean) => x |
| 499 | } |
| 500 | if (input_type->Is(Type::Undefined())) { |
| 501 | // JSToBoolean(undefined) => #false |
| 502 | return ReplaceWith(jsgraph()->FalseConstant()); |
| 503 | } |
| 504 | if (input_type->Is(Type::Null())) { |
| 505 | // JSToBoolean(null) => #false |
| 506 | return ReplaceWith(jsgraph()->FalseConstant()); |
| 507 | } |
| 508 | if (input_type->Is(Type::DetectableReceiver())) { |
| 509 | // JSToBoolean(x:detectable) => #true |
| 510 | return ReplaceWith(jsgraph()->TrueConstant()); |
| 511 | } |
| 512 | if (input_type->Is(Type::Undetectable())) { |
| 513 | // JSToBoolean(x:undetectable) => #false |
| 514 | return ReplaceWith(jsgraph()->FalseConstant()); |
| 515 | } |
| 516 | if (input_type->Is(Type::OrderedNumber())) { |
| 517 | // JSToBoolean(x:ordered-number) => BooleanNot(NumberEqual(x, #0)) |
| 518 | Node* cmp = graph()->NewNode(simplified()->NumberEqual(), input, |
| 519 | jsgraph()->ZeroConstant()); |
| 520 | Node* inv = graph()->NewNode(simplified()->BooleanNot(), cmp); |
| 521 | return ReplaceWith(inv); |
| 522 | } |
| 523 | // TODO(turbofan): js-typed-lowering of ToBoolean(string) |
| 524 | return NoChange(); |
| 525 | } |
| 526 | |
| 527 | |
| 528 | Reduction JSTypedLowering::ReduceJSLoadProperty(Node* node) { |
| 529 | Node* key = NodeProperties::GetValueInput(node, 1); |
| 530 | Node* base = NodeProperties::GetValueInput(node, 0); |
| 531 | Type* key_type = NodeProperties::GetBounds(key).upper; |
| 532 | Type* base_type = NodeProperties::GetBounds(base).upper; |
| 533 | // TODO(mstarzinger): This lowering is not correct if: |
| 534 | // a) The typed array turns external (i.e. MaterializeArrayBuffer) |
| 535 | // b) The typed array or it's buffer is neutered. |
| 536 | // c) The index is out of bounds. |
| 537 | if (base_type->IsConstant() && key_type->Is(Type::Integral32()) && |
| 538 | base_type->AsConstant()->Value()->IsJSTypedArray()) { |
| 539 | // JSLoadProperty(typed-array, int32) |
| 540 | JSTypedArray* array = JSTypedArray::cast(*base_type->AsConstant()->Value()); |
| 541 | ElementsKind elements_kind = array->map()->elements_kind(); |
| 542 | ExternalArrayType type = array->type(); |
| 543 | uint32_t length; |
| 544 | CHECK(array->length()->ToUint32(&length)); |
| 545 | ElementAccess element_access; |
| 546 | Node* elements = graph()->NewNode( |
| 547 | simplified()->LoadField(AccessBuilder::ForJSObjectElements()), base, |
| 548 | NodeProperties::GetEffectInput(node)); |
| 549 | if (IsExternalArrayElementsKind(elements_kind)) { |
| 550 | elements = graph()->NewNode( |
| 551 | simplified()->LoadField(AccessBuilder::ForExternalArrayPointer()), |
| 552 | elements, NodeProperties::GetEffectInput(node)); |
| 553 | element_access = AccessBuilder::ForTypedArrayElement(type, true); |
| 554 | } else { |
| 555 | DCHECK(IsFixedTypedArrayElementsKind(elements_kind)); |
| 556 | element_access = AccessBuilder::ForTypedArrayElement(type, false); |
| 557 | } |
| 558 | Node* value = |
| 559 | graph()->NewNode(simplified()->LoadElement(element_access), elements, |
| 560 | key, jsgraph()->Uint32Constant(length), |
| 561 | NodeProperties::GetEffectInput(node)); |
| 562 | return ReplaceEagerly(node, value); |
| 563 | } |
| 564 | return NoChange(); |
| 565 | } |
| 566 | |
| 567 | |
| 568 | Reduction JSTypedLowering::ReduceJSStoreProperty(Node* node) { |
| 569 | Node* key = NodeProperties::GetValueInput(node, 1); |
| 570 | Node* base = NodeProperties::GetValueInput(node, 0); |
| 571 | Node* value = NodeProperties::GetValueInput(node, 2); |
| 572 | Type* key_type = NodeProperties::GetBounds(key).upper; |
| 573 | Type* base_type = NodeProperties::GetBounds(base).upper; |
| 574 | // TODO(mstarzinger): This lowering is not correct if: |
| 575 | // a) The typed array turns external (i.e. MaterializeArrayBuffer) |
| 576 | // b) The typed array or it's buffer is neutered. |
| 577 | if (key_type->Is(Type::Integral32()) && base_type->IsConstant() && |
| 578 | base_type->AsConstant()->Value()->IsJSTypedArray()) { |
| 579 | // JSStoreProperty(typed-array, int32, value) |
| 580 | JSTypedArray* array = JSTypedArray::cast(*base_type->AsConstant()->Value()); |
| 581 | ElementsKind elements_kind = array->map()->elements_kind(); |
| 582 | ExternalArrayType type = array->type(); |
| 583 | uint32_t length; |
| 584 | CHECK(array->length()->ToUint32(&length)); |
| 585 | ElementAccess element_access; |
| 586 | Node* elements = graph()->NewNode( |
| 587 | simplified()->LoadField(AccessBuilder::ForJSObjectElements()), base, |
| 588 | NodeProperties::GetEffectInput(node)); |
| 589 | if (IsExternalArrayElementsKind(elements_kind)) { |
| 590 | elements = graph()->NewNode( |
| 591 | simplified()->LoadField(AccessBuilder::ForExternalArrayPointer()), |
| 592 | elements, NodeProperties::GetEffectInput(node)); |
| 593 | element_access = AccessBuilder::ForTypedArrayElement(type, true); |
| 594 | } else { |
| 595 | DCHECK(IsFixedTypedArrayElementsKind(elements_kind)); |
| 596 | element_access = AccessBuilder::ForTypedArrayElement(type, false); |
| 597 | } |
| 598 | |
| 599 | Node* check = graph()->NewNode(machine()->Uint32LessThan(), key, |
| 600 | jsgraph()->Uint32Constant(length)); |
| 601 | Node* branch = graph()->NewNode(common()->Branch(), check, |
| 602 | NodeProperties::GetControlInput(node)); |
| 603 | |
| 604 | Node* if_true = graph()->NewNode(common()->IfTrue(), branch); |
| 605 | Node* store = |
| 606 | graph()->NewNode(simplified()->StoreElement(element_access), elements, |
| 607 | key, jsgraph()->Uint32Constant(length), value, |
| 608 | NodeProperties::GetEffectInput(node), if_true); |
| 609 | |
| 610 | Node* if_false = graph()->NewNode(common()->IfFalse(), branch); |
| 611 | |
| 612 | Node* merge = graph()->NewNode(common()->Merge(2), if_true, if_false); |
| 613 | Node* phi = graph()->NewNode(common()->EffectPhi(2), store, |
| 614 | NodeProperties::GetEffectInput(node), merge); |
| 615 | |
| 616 | return ReplaceWith(phi); |
| 617 | } |
| 618 | return NoChange(); |
| 619 | } |
| 620 | |
| 621 | |
| 622 | static Reduction ReplaceWithReduction(Node* node, Reduction reduction) { |
| 623 | if (reduction.Changed()) { |
| 624 | NodeProperties::ReplaceWithValue(node, reduction.replacement()); |
| 625 | return reduction; |
| 626 | } |
| 627 | return Reducer::NoChange(); |
| 628 | } |
| 629 | |
| 630 | |
| 631 | Reduction JSTypedLowering::Reduce(Node* node) { |
| 632 | switch (node->opcode()) { |
| 633 | case IrOpcode::kJSEqual: |
| 634 | return ReduceJSEqual(node, false); |
| 635 | case IrOpcode::kJSNotEqual: |
| 636 | return ReduceJSEqual(node, true); |
| 637 | case IrOpcode::kJSStrictEqual: |
| 638 | return ReduceJSStrictEqual(node, false); |
| 639 | case IrOpcode::kJSStrictNotEqual: |
| 640 | return ReduceJSStrictEqual(node, true); |
| 641 | case IrOpcode::kJSLessThan: // fall through |
| 642 | case IrOpcode::kJSGreaterThan: // fall through |
| 643 | case IrOpcode::kJSLessThanOrEqual: // fall through |
| 644 | case IrOpcode::kJSGreaterThanOrEqual: |
| 645 | return ReduceJSComparison(node); |
| 646 | case IrOpcode::kJSBitwiseOr: |
| 647 | return ReduceI32Binop(node, true, true, machine()->Word32Or()); |
| 648 | case IrOpcode::kJSBitwiseXor: |
| 649 | return ReduceI32Binop(node, true, true, machine()->Word32Xor()); |
| 650 | case IrOpcode::kJSBitwiseAnd: |
| 651 | return ReduceI32Binop(node, true, true, machine()->Word32And()); |
| 652 | case IrOpcode::kJSShiftLeft: |
| 653 | return ReduceI32Shift(node, true, machine()->Word32Shl()); |
| 654 | case IrOpcode::kJSShiftRight: |
| 655 | return ReduceI32Shift(node, true, machine()->Word32Sar()); |
| 656 | case IrOpcode::kJSShiftRightLogical: |
| 657 | return ReduceI32Shift(node, false, machine()->Word32Shr()); |
| 658 | case IrOpcode::kJSAdd: |
| 659 | return ReduceJSAdd(node); |
| 660 | case IrOpcode::kJSSubtract: |
| 661 | return ReduceNumberBinop(node, simplified()->NumberSubtract()); |
| 662 | case IrOpcode::kJSMultiply: |
| 663 | return ReduceNumberBinop(node, simplified()->NumberMultiply()); |
| 664 | case IrOpcode::kJSDivide: |
| 665 | return ReduceNumberBinop(node, simplified()->NumberDivide()); |
| 666 | case IrOpcode::kJSModulus: |
| 667 | return ReduceNumberBinop(node, simplified()->NumberModulus()); |
| 668 | case IrOpcode::kJSUnaryNot: { |
| 669 | Reduction result = ReduceJSToBooleanInput(node->InputAt(0)); |
| 670 | Node* value; |
| 671 | if (result.Changed()) { |
| 672 | // JSUnaryNot(x:boolean) => BooleanNot(x) |
| 673 | value = |
| 674 | graph()->NewNode(simplified()->BooleanNot(), result.replacement()); |
| 675 | NodeProperties::ReplaceWithValue(node, value); |
| 676 | return Changed(value); |
| 677 | } else { |
| 678 | // JSUnaryNot(x) => BooleanNot(JSToBoolean(x)) |
| 679 | value = graph()->NewNode(simplified()->BooleanNot(), node); |
| 680 | node->set_op(javascript()->ToBoolean()); |
| 681 | NodeProperties::ReplaceWithValue(node, value, node); |
| 682 | // Note: ReplaceUses() smashes all uses, so smash it back here. |
| 683 | value->ReplaceInput(0, node); |
| 684 | return Changed(node); |
| 685 | } |
| 686 | } |
| 687 | case IrOpcode::kJSToBoolean: |
| 688 | return ReplaceWithReduction(node, |
| 689 | ReduceJSToBooleanInput(node->InputAt(0))); |
| 690 | case IrOpcode::kJSToNumber: |
| 691 | return ReplaceWithReduction(node, |
| 692 | ReduceJSToNumberInput(node->InputAt(0))); |
| 693 | case IrOpcode::kJSToString: |
| 694 | return ReplaceWithReduction(node, |
| 695 | ReduceJSToStringInput(node->InputAt(0))); |
| 696 | case IrOpcode::kJSLoadProperty: |
| 697 | return ReduceJSLoadProperty(node); |
| 698 | case IrOpcode::kJSStoreProperty: |
| 699 | return ReduceJSStoreProperty(node); |
| 700 | case IrOpcode::kJSCallFunction: |
| 701 | return JSBuiltinReducer(jsgraph()).Reduce(node); |
| 702 | default: |
| 703 | break; |
| 704 | } |
| 705 | return NoChange(); |
| 706 | } |
| 707 | |
| 708 | } // namespace compiler |
| 709 | } // namespace internal |
| 710 | } // namespace v8 |