1 // Copyright 2013 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 #ifndef V8_CRANKSHAFT_ARM64_LITHIUM_CODEGEN_ARM64_H_
6 #define V8_CRANKSHAFT_ARM64_LITHIUM_CODEGEN_ARM64_H_
7 
8 #include "src/crankshaft/arm64/lithium-arm64.h"
9 
10 #include "src/ast/scopes.h"
11 #include "src/crankshaft/arm64/lithium-gap-resolver-arm64.h"
12 #include "src/crankshaft/lithium-codegen.h"
13 #include "src/deoptimizer.h"
14 #include "src/safepoint-table.h"
15 #include "src/utils.h"
16 
17 namespace v8 {
18 namespace internal {
19 
20 // Forward declarations.
21 class LDeferredCode;
22 class SafepointGenerator;
23 class BranchGenerator;
24 
25 class LCodeGen: public LCodeGenBase {
26  public:
LCodeGen(LChunk * chunk,MacroAssembler * assembler,CompilationInfo * info)27   LCodeGen(LChunk* chunk, MacroAssembler* assembler, CompilationInfo* info)
28       : LCodeGenBase(chunk, assembler, info),
29         jump_table_(4, info->zone()),
30         scope_(info->scope()),
31         deferred_(8, info->zone()),
32         frame_is_built_(false),
33         safepoints_(info->zone()),
34         resolver_(this),
35         expected_safepoint_kind_(Safepoint::kSimple),
36         pushed_arguments_(0) {
37     PopulateDeoptimizationLiteralsWithInlinedFunctions();
38   }
39 
40   // Simple accessors.
scope()41   Scope* scope() const { return scope_; }
42 
LookupDestination(int block_id)43   int LookupDestination(int block_id) const {
44     return chunk()->LookupDestination(block_id);
45   }
46 
IsNextEmittedBlock(int block_id)47   bool IsNextEmittedBlock(int block_id) const {
48     return LookupDestination(block_id) == GetNextEmittedBlock();
49   }
50 
NeedsEagerFrame()51   bool NeedsEagerFrame() const {
52     return HasAllocatedStackSlots() || info()->is_non_deferred_calling() ||
53            !info()->IsStub() || info()->requires_frame();
54   }
NeedsDeferredFrame()55   bool NeedsDeferredFrame() const {
56     return !NeedsEagerFrame() && info()->is_deferred_calling();
57   }
58 
GetLinkRegisterState()59   LinkRegisterStatus GetLinkRegisterState() const {
60     return frame_is_built_ ? kLRHasBeenSaved : kLRHasNotBeenSaved;
61   }
62 
63   // Try to generate code for the entire chunk, but it may fail if the
64   // chunk contains constructs we cannot handle. Returns true if the
65   // code generation attempt succeeded.
66   bool GenerateCode();
67 
68   // Finish the code by setting stack height, safepoint, and bailout
69   // information on it.
70   void FinishCode(Handle<Code> code);
71 
72   enum IntegerSignedness { SIGNED_INT32, UNSIGNED_INT32 };
73   // Support for converting LOperands to assembler types.
74   Register ToRegister(LOperand* op) const;
75   Register ToRegister32(LOperand* op) const;
76   Operand ToOperand(LOperand* op);
77   Operand ToOperand32(LOperand* op);
78   enum StackMode { kMustUseFramePointer, kCanUseStackPointer };
79   MemOperand ToMemOperand(LOperand* op,
80                           StackMode stack_mode = kCanUseStackPointer) const;
81   Handle<Object> ToHandle(LConstantOperand* op) const;
82 
83   template <class LI>
84   Operand ToShiftedRightOperand32(LOperand* right, LI* shift_info);
85 
JSShiftAmountFromLConstant(LOperand * constant)86   int JSShiftAmountFromLConstant(LOperand* constant) {
87     return ToInteger32(LConstantOperand::cast(constant)) & 0x1f;
88   }
89 
90   // TODO(jbramley): Examine these helpers and check that they make sense.
91   // IsInteger32Constant returns true for smi constants, for example.
92   bool IsInteger32Constant(LConstantOperand* op) const;
93   bool IsSmi(LConstantOperand* op) const;
94 
95   int32_t ToInteger32(LConstantOperand* op) const;
96   Smi* ToSmi(LConstantOperand* op) const;
97   double ToDouble(LConstantOperand* op) const;
98   DoubleRegister ToDoubleRegister(LOperand* op) const;
99 
100   // Declare methods that deal with the individual node types.
101 #define DECLARE_DO(type) void Do##type(L##type* node);
LITHIUM_CONCRETE_INSTRUCTION_LIST(DECLARE_DO)102   LITHIUM_CONCRETE_INSTRUCTION_LIST(DECLARE_DO)
103 #undef DECLARE_DO
104 
105  private:
106   // Return a double scratch register which can be used locally
107   // when generating code for a lithium instruction.
108   DoubleRegister double_scratch() { return crankshaft_fp_scratch; }
109 
110   // Deferred code support.
111   void DoDeferredNumberTagD(LNumberTagD* instr);
112   void DoDeferredStackCheck(LStackCheck* instr);
113   void DoDeferredMaybeGrowElements(LMaybeGrowElements* instr);
114   void DoDeferredStringCharCodeAt(LStringCharCodeAt* instr);
115   void DoDeferredStringCharFromCode(LStringCharFromCode* instr);
116   void DoDeferredMathAbsTagged(LMathAbsTagged* instr,
117                                Label* exit,
118                                Label* allocation_entry);
119 
120   void DoDeferredNumberTagU(LInstruction* instr,
121                             LOperand* value,
122                             LOperand* temp1,
123                             LOperand* temp2);
124   void DoDeferredTaggedToI(LTaggedToI* instr,
125                            LOperand* value,
126                            LOperand* temp1,
127                            LOperand* temp2);
128   void DoDeferredAllocate(LAllocate* instr);
129   void DoDeferredInstanceMigration(LCheckMaps* instr, Register object);
130   void DoDeferredLoadMutableDouble(LLoadFieldByIndex* instr,
131                                    Register result,
132                                    Register object,
133                                    Register index);
134 
135   static Condition TokenToCondition(Token::Value op, bool is_unsigned);
136   void EmitGoto(int block);
137   void DoGap(LGap* instr);
138 
139   // Generic version of EmitBranch. It contains some code to avoid emitting a
140   // branch on the next emitted basic block where we could just fall-through.
141   // You shouldn't use that directly but rather consider one of the helper like
142   // LCodeGen::EmitBranch, LCodeGen::EmitCompareAndBranch...
143   template<class InstrType>
144   void EmitBranchGeneric(InstrType instr,
145                          const BranchGenerator& branch);
146 
147   template<class InstrType>
148   void EmitBranch(InstrType instr, Condition condition);
149 
150   template<class InstrType>
151   void EmitCompareAndBranch(InstrType instr,
152                             Condition condition,
153                             const Register& lhs,
154                             const Operand& rhs);
155 
156   template<class InstrType>
157   void EmitTestAndBranch(InstrType instr,
158                          Condition condition,
159                          const Register& value,
160                          uint64_t mask);
161 
162   template<class InstrType>
163   void EmitBranchIfNonZeroNumber(InstrType instr,
164                                  const FPRegister& value,
165                                  const FPRegister& scratch);
166 
167   template<class InstrType>
168   void EmitBranchIfHeapNumber(InstrType instr,
169                               const Register& value);
170 
171   template<class InstrType>
172   void EmitBranchIfRoot(InstrType instr,
173                         const Register& value,
174                         Heap::RootListIndex index);
175 
176   // Emits optimized code to deep-copy the contents of statically known object
177   // graphs (e.g. object literal boilerplate). Expects a pointer to the
178   // allocated destination object in the result register, and a pointer to the
179   // source object in the source register.
180   void EmitDeepCopy(Handle<JSObject> object,
181                     Register result,
182                     Register source,
183                     Register scratch,
184                     int* offset,
185                     AllocationSiteMode mode);
186 
187   template <class T>
188   void EmitVectorLoadICRegisters(T* instr);
189 
190   // Emits optimized code for %_IsString(x).  Preserves input register.
191   // Returns the condition on which a final split to
192   // true and false label should be made, to optimize fallthrough.
193   Condition EmitIsString(Register input, Register temp1, Label* is_not_string,
194                          SmiCheck check_needed);
195 
196   MemOperand BuildSeqStringOperand(Register string,
197                                    Register temp,
198                                    LOperand* index,
199                                    String::Encoding encoding);
200   void DeoptimizeBranch(LInstruction* instr, DeoptimizeReason deopt_reason,
201                         BranchType branch_type, Register reg = NoReg,
202                         int bit = -1,
203                         Deoptimizer::BailoutType* override_bailout_type = NULL);
204   void Deoptimize(LInstruction* instr, DeoptimizeReason deopt_reason,
205                   Deoptimizer::BailoutType* override_bailout_type = NULL);
206   void DeoptimizeIf(Condition cond, LInstruction* instr,
207                     DeoptimizeReason deopt_reason);
208   void DeoptimizeIfZero(Register rt, LInstruction* instr,
209                         DeoptimizeReason deopt_reason);
210   void DeoptimizeIfNotZero(Register rt, LInstruction* instr,
211                            DeoptimizeReason deopt_reason);
212   void DeoptimizeIfNegative(Register rt, LInstruction* instr,
213                             DeoptimizeReason deopt_reason);
214   void DeoptimizeIfSmi(Register rt, LInstruction* instr,
215                        DeoptimizeReason deopt_reason);
216   void DeoptimizeIfNotSmi(Register rt, LInstruction* instr,
217                           DeoptimizeReason deopt_reason);
218   void DeoptimizeIfRoot(Register rt, Heap::RootListIndex index,
219                         LInstruction* instr, DeoptimizeReason deopt_reason);
220   void DeoptimizeIfNotRoot(Register rt, Heap::RootListIndex index,
221                            LInstruction* instr, DeoptimizeReason deopt_reason);
222   void DeoptimizeIfNotHeapNumber(Register object, LInstruction* instr);
223   void DeoptimizeIfMinusZero(DoubleRegister input, LInstruction* instr,
224                              DeoptimizeReason deopt_reason);
225   void DeoptimizeIfBitSet(Register rt, int bit, LInstruction* instr,
226                           DeoptimizeReason deopt_reason);
227   void DeoptimizeIfBitClear(Register rt, int bit, LInstruction* instr,
228                             DeoptimizeReason deopt_reason);
229 
230   MemOperand PrepareKeyedExternalArrayOperand(Register key,
231                                               Register base,
232                                               Register scratch,
233                                               bool key_is_smi,
234                                               bool key_is_constant,
235                                               int constant_key,
236                                               ElementsKind elements_kind,
237                                               int base_offset);
238   MemOperand PrepareKeyedArrayOperand(Register base,
239                                       Register elements,
240                                       Register key,
241                                       bool key_is_tagged,
242                                       ElementsKind elements_kind,
243                                       Representation representation,
244                                       int base_offset);
245 
246   void RegisterEnvironmentForDeoptimization(LEnvironment* environment,
247                                             Safepoint::DeoptMode mode);
248 
HasAllocatedStackSlots()249   bool HasAllocatedStackSlots() const {
250     return chunk()->HasAllocatedStackSlots();
251   }
GetStackSlotCount()252   int GetStackSlotCount() const { return chunk()->GetSpillSlotCount(); }
GetTotalFrameSlotCount()253   int GetTotalFrameSlotCount() const {
254     return chunk()->GetTotalFrameSlotCount();
255   }
256 
AddDeferredCode(LDeferredCode * code)257   void AddDeferredCode(LDeferredCode* code) { deferred_.Add(code, zone()); }
258 
259   // Emit frame translation commands for an environment.
260   void WriteTranslation(LEnvironment* environment, Translation* translation);
261 
262   void AddToTranslation(LEnvironment* environment,
263                         Translation* translation,
264                         LOperand* op,
265                         bool is_tagged,
266                         bool is_uint32,
267                         int* object_index_pointer,
268                         int* dematerialized_index_pointer);
269 
270   void SaveCallerDoubles();
271   void RestoreCallerDoubles();
272 
273   // Code generation steps.  Returns true if code generation should continue.
274   void GenerateBodyInstructionPre(LInstruction* instr) override;
275   bool GeneratePrologue();
276   bool GenerateDeferredCode();
277   bool GenerateJumpTable();
278   bool GenerateSafepointTable();
279 
280   // Generates the custom OSR entrypoint and sets the osr_pc_offset.
281   void GenerateOsrPrologue();
282 
283   enum SafepointMode {
284     RECORD_SIMPLE_SAFEPOINT,
285     RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS
286   };
287 
288   void CallCode(Handle<Code> code,
289                 RelocInfo::Mode mode,
290                 LInstruction* instr);
291 
292   void CallCodeGeneric(Handle<Code> code,
293                        RelocInfo::Mode mode,
294                        LInstruction* instr,
295                        SafepointMode safepoint_mode);
296 
297   void CallRuntime(const Runtime::Function* function,
298                    int num_arguments,
299                    LInstruction* instr,
300                    SaveFPRegsMode save_doubles = kDontSaveFPRegs);
301 
CallRuntime(Runtime::FunctionId id,int num_arguments,LInstruction * instr)302   void CallRuntime(Runtime::FunctionId id,
303                    int num_arguments,
304                    LInstruction* instr) {
305     const Runtime::Function* function = Runtime::FunctionForId(id);
306     CallRuntime(function, num_arguments, instr);
307   }
308 
CallRuntime(Runtime::FunctionId id,LInstruction * instr)309   void CallRuntime(Runtime::FunctionId id, LInstruction* instr) {
310     const Runtime::Function* function = Runtime::FunctionForId(id);
311     CallRuntime(function, function->nargs, instr);
312   }
313 
314   void LoadContextFromDeferred(LOperand* context);
315   void CallRuntimeFromDeferred(Runtime::FunctionId id,
316                                int argc,
317                                LInstruction* instr,
318                                LOperand* context);
319 
320   void PrepareForTailCall(const ParameterCount& actual, Register scratch1,
321                           Register scratch2, Register scratch3);
322 
323   // Generate a direct call to a known function.  Expects the function
324   // to be in x1.
325   void CallKnownFunction(Handle<JSFunction> function,
326                          int formal_parameter_count, int arity,
327                          bool is_tail_call, LInstruction* instr);
328 
329   // Support for recording safepoint information.
330   void RecordSafepoint(LPointerMap* pointers,
331                        Safepoint::Kind kind,
332                        int arguments,
333                        Safepoint::DeoptMode mode);
334   void RecordSafepoint(LPointerMap* pointers, Safepoint::DeoptMode mode);
335   void RecordSafepoint(Safepoint::DeoptMode mode);
336   void RecordSafepointWithRegisters(LPointerMap* pointers,
337                                     int arguments,
338                                     Safepoint::DeoptMode mode);
339   void RecordSafepointWithLazyDeopt(LInstruction* instr,
340                                     SafepointMode safepoint_mode);
341 
342   void EnsureSpaceForLazyDeopt(int space_needed) override;
343 
344   ZoneList<Deoptimizer::JumpTableEntry*> jump_table_;
345   Scope* const scope_;
346   ZoneList<LDeferredCode*> deferred_;
347   bool frame_is_built_;
348 
349   // Builder that keeps track of safepoints in the code. The table itself is
350   // emitted at the end of the generated code.
351   SafepointTableBuilder safepoints_;
352 
353   // Compiler from a set of parallel moves to a sequential list of moves.
354   LGapResolver resolver_;
355 
356   Safepoint::Kind expected_safepoint_kind_;
357 
358   // The number of arguments pushed onto the stack, either by this block or by a
359   // predecessor.
360   int pushed_arguments_;
361 
RecordPushedArgumentsDelta(int delta)362   void RecordPushedArgumentsDelta(int delta) {
363     pushed_arguments_ += delta;
364     DCHECK(pushed_arguments_ >= 0);
365   }
366 
367   int old_position_;
368 
369   class PushSafepointRegistersScope BASE_EMBEDDED {
370    public:
371     explicit PushSafepointRegistersScope(LCodeGen* codegen);
372 
373     ~PushSafepointRegistersScope();
374 
375    private:
376     LCodeGen* codegen_;
377   };
378 
379   friend class LDeferredCode;
380   friend class SafepointGenerator;
381   DISALLOW_COPY_AND_ASSIGN(LCodeGen);
382 };
383 
384 
385 class LDeferredCode: public ZoneObject {
386  public:
LDeferredCode(LCodeGen * codegen)387   explicit LDeferredCode(LCodeGen* codegen)
388       : codegen_(codegen),
389         external_exit_(NULL),
390         instruction_index_(codegen->current_instruction_) {
391     codegen->AddDeferredCode(this);
392   }
393 
~LDeferredCode()394   virtual ~LDeferredCode() { }
395   virtual void Generate() = 0;
396   virtual LInstruction* instr() = 0;
397 
SetExit(Label * exit)398   void SetExit(Label* exit) { external_exit_ = exit; }
entry()399   Label* entry() { return &entry_; }
exit()400   Label* exit() { return (external_exit_ != NULL) ? external_exit_ : &exit_; }
instruction_index()401   int instruction_index() const { return instruction_index_; }
402 
403  protected:
codegen()404   LCodeGen* codegen() const { return codegen_; }
masm()405   MacroAssembler* masm() const { return codegen_->masm(); }
406 
407  private:
408   LCodeGen* codegen_;
409   Label entry_;
410   Label exit_;
411   Label* external_exit_;
412   int instruction_index_;
413 };
414 
415 
416 // This is the abstract class used by EmitBranchGeneric.
417 // It is used to emit code for conditional branching. The Emit() function
418 // emits code to branch when the condition holds and EmitInverted() emits
419 // the branch when the inverted condition is verified.
420 //
421 // For actual examples of condition see the concrete implementation in
422 // lithium-codegen-arm64.cc (e.g. BranchOnCondition, CompareAndBranch).
423 class BranchGenerator BASE_EMBEDDED {
424  public:
BranchGenerator(LCodeGen * codegen)425   explicit BranchGenerator(LCodeGen* codegen)
426     : codegen_(codegen) { }
427 
~BranchGenerator()428   virtual ~BranchGenerator() { }
429 
430   virtual void Emit(Label* label) const = 0;
431   virtual void EmitInverted(Label* label) const = 0;
432 
433  protected:
masm()434   MacroAssembler* masm() const { return codegen_->masm(); }
435 
436   LCodeGen* codegen_;
437 };
438 
439 }  // namespace internal
440 }  // namespace v8
441 
442 #endif  // V8_CRANKSHAFT_ARM64_LITHIUM_CODEGEN_ARM64_H_
443