1// Copyright 2012 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_MIPS_MACRO_ASSEMBLER_MIPS_H_
6#define V8_MIPS_MACRO_ASSEMBLER_MIPS_H_
7
8#include "src/assembler.h"
9#include "src/globals.h"
10#include "src/mips/assembler-mips.h"
11
12namespace v8 {
13namespace internal {
14
15// Forward declaration.
16class JumpTarget;
17
18// Reserved Register Usage Summary.
19//
20// Registers t8, t9, and at are reserved for use by the MacroAssembler.
21//
22// The programmer should know that the MacroAssembler may clobber these three,
23// but won't touch other registers except in special cases.
24//
25// Per the MIPS ABI, register t9 must be used for indirect function call
26// via 'jalr t9' or 'jr t9' instructions. This is relied upon by gcc when
27// trying to update gp register for position-independent-code. Whenever
28// MIPS generated code calls C code, it must be via t9 register.
29
30
31// Flags used for LeaveExitFrame function.
32enum LeaveExitFrameMode {
33  EMIT_RETURN = true,
34  NO_EMIT_RETURN = false
35};
36
37// Flags used for AllocateHeapNumber
38enum TaggingMode {
39  // Tag the result.
40  TAG_RESULT,
41  // Don't tag
42  DONT_TAG_RESULT
43};
44
45// Flags used for the ObjectToDoubleFPURegister function.
46enum ObjectToDoubleFlags {
47  // No special flags.
48  NO_OBJECT_TO_DOUBLE_FLAGS = 0,
49  // Object is known to be a non smi.
50  OBJECT_NOT_SMI = 1 << 0,
51  // Don't load NaNs or infinities, branch to the non number case instead.
52  AVOID_NANS_AND_INFINITIES = 1 << 1
53};
54
55// Allow programmer to use Branch Delay Slot of Branches, Jumps, Calls.
56enum BranchDelaySlot {
57  USE_DELAY_SLOT,
58  PROTECT
59};
60
61// Flags used for the li macro-assembler function.
62enum LiFlags {
63  // If the constant value can be represented in just 16 bits, then
64  // optimize the li to use a single instruction, rather than lui/ori pair.
65  OPTIMIZE_SIZE = 0,
66  // Always use 2 instructions (lui/ori pair), even if the constant could
67  // be loaded with just one, so that this value is patchable later.
68  CONSTANT_SIZE = 1
69};
70
71
72enum RememberedSetAction { EMIT_REMEMBERED_SET, OMIT_REMEMBERED_SET };
73enum SmiCheck { INLINE_SMI_CHECK, OMIT_SMI_CHECK };
74enum PointersToHereCheck {
75  kPointersToHereMaybeInteresting,
76  kPointersToHereAreAlwaysInteresting
77};
78enum RAStatus { kRAHasNotBeenSaved, kRAHasBeenSaved };
79
80Register GetRegisterThatIsNotOneOf(Register reg1,
81                                   Register reg2 = no_reg,
82                                   Register reg3 = no_reg,
83                                   Register reg4 = no_reg,
84                                   Register reg5 = no_reg,
85                                   Register reg6 = no_reg);
86
87bool AreAliased(Register reg1,
88                Register reg2,
89                Register reg3 = no_reg,
90                Register reg4 = no_reg,
91                Register reg5 = no_reg,
92                Register reg6 = no_reg,
93                Register reg7 = no_reg,
94                Register reg8 = no_reg);
95
96
97// -----------------------------------------------------------------------------
98// Static helper functions.
99
100inline MemOperand ContextOperand(Register context, int index) {
101  return MemOperand(context, Context::SlotOffset(index));
102}
103
104
105inline MemOperand GlobalObjectOperand()  {
106  return ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX);
107}
108
109
110// Generate a MemOperand for loading a field from an object.
111inline MemOperand FieldMemOperand(Register object, int offset) {
112  return MemOperand(object, offset - kHeapObjectTag);
113}
114
115
116// Generate a MemOperand for storing arguments 5..N on the stack
117// when calling CallCFunction().
118inline MemOperand CFunctionArgumentOperand(int index) {
119  DCHECK(index > kCArgSlotCount);
120  // Argument 5 takes the slot just past the four Arg-slots.
121  int offset = (index - 5) * kPointerSize + kCArgsSlotsSize;
122  return MemOperand(sp, offset);
123}
124
125
126// MacroAssembler implements a collection of frequently used macros.
127class MacroAssembler: public Assembler {
128 public:
129  // The isolate parameter can be NULL if the macro assembler should
130  // not use isolate-dependent functionality. In this case, it's the
131  // responsibility of the caller to never invoke such function on the
132  // macro assembler.
133  MacroAssembler(Isolate* isolate, void* buffer, int size);
134
135  // Arguments macros.
136#define COND_TYPED_ARGS Condition cond, Register r1, const Operand& r2
137#define COND_ARGS cond, r1, r2
138
139  // Cases when relocation is not needed.
140#define DECLARE_NORELOC_PROTOTYPE(Name, target_type) \
141  void Name(target_type target, BranchDelaySlot bd = PROTECT); \
142  inline void Name(BranchDelaySlot bd, target_type target) { \
143    Name(target, bd); \
144  } \
145  void Name(target_type target, \
146            COND_TYPED_ARGS, \
147            BranchDelaySlot bd = PROTECT); \
148  inline void Name(BranchDelaySlot bd, \
149                   target_type target, \
150                   COND_TYPED_ARGS) { \
151    Name(target, COND_ARGS, bd); \
152  }
153
154#define DECLARE_BRANCH_PROTOTYPES(Name) \
155  DECLARE_NORELOC_PROTOTYPE(Name, Label*) \
156  DECLARE_NORELOC_PROTOTYPE(Name, int16_t)
157
158  DECLARE_BRANCH_PROTOTYPES(Branch)
159  DECLARE_BRANCH_PROTOTYPES(BranchAndLink)
160  DECLARE_BRANCH_PROTOTYPES(BranchShort)
161
162#undef DECLARE_BRANCH_PROTOTYPES
163#undef COND_TYPED_ARGS
164#undef COND_ARGS
165
166
167  // Jump, Call, and Ret pseudo instructions implementing inter-working.
168#define COND_ARGS Condition cond = al, Register rs = zero_reg, \
169  const Operand& rt = Operand(zero_reg), BranchDelaySlot bd = PROTECT
170
171  void Jump(Register target, COND_ARGS);
172  void Jump(intptr_t target, RelocInfo::Mode rmode, COND_ARGS);
173  void Jump(Address target, RelocInfo::Mode rmode, COND_ARGS);
174  void Jump(Handle<Code> code, RelocInfo::Mode rmode, COND_ARGS);
175  static int CallSize(Register target, COND_ARGS);
176  void Call(Register target, COND_ARGS);
177  static int CallSize(Address target, RelocInfo::Mode rmode, COND_ARGS);
178  void Call(Address target, RelocInfo::Mode rmode, COND_ARGS);
179  int CallSize(Handle<Code> code,
180               RelocInfo::Mode rmode = RelocInfo::CODE_TARGET,
181               TypeFeedbackId ast_id = TypeFeedbackId::None(),
182               COND_ARGS);
183  void Call(Handle<Code> code,
184            RelocInfo::Mode rmode = RelocInfo::CODE_TARGET,
185            TypeFeedbackId ast_id = TypeFeedbackId::None(),
186            COND_ARGS);
187  void Ret(COND_ARGS);
188  inline void Ret(BranchDelaySlot bd, Condition cond = al,
189    Register rs = zero_reg, const Operand& rt = Operand(zero_reg)) {
190    Ret(cond, rs, rt, bd);
191  }
192
193  void Branch(Label* L,
194              Condition cond,
195              Register rs,
196              Heap::RootListIndex index,
197              BranchDelaySlot bdslot = PROTECT);
198
199#undef COND_ARGS
200
201  // Emit code to discard a non-negative number of pointer-sized elements
202  // from the stack, clobbering only the sp register.
203  void Drop(int count,
204            Condition cond = cc_always,
205            Register reg = no_reg,
206            const Operand& op = Operand(no_reg));
207
208  // Trivial case of DropAndRet that utilizes the delay slot and only emits
209  // 2 instructions.
210  void DropAndRet(int drop);
211
212  void DropAndRet(int drop,
213                  Condition cond,
214                  Register reg,
215                  const Operand& op);
216
217  // Swap two registers.  If the scratch register is omitted then a slightly
218  // less efficient form using xor instead of mov is emitted.
219  void Swap(Register reg1, Register reg2, Register scratch = no_reg);
220
221  void Call(Label* target);
222
223  inline void Move(Register dst, Register src) {
224    if (!dst.is(src)) {
225      mov(dst, src);
226    }
227  }
228
229  inline void Move(FPURegister dst, FPURegister src) {
230    if (!dst.is(src)) {
231      mov_d(dst, src);
232    }
233  }
234
235  inline void Move(Register dst_low, Register dst_high, FPURegister src) {
236    mfc1(dst_low, src);
237    Mfhc1(dst_high, src);
238  }
239
240  inline void FmoveHigh(Register dst_high, FPURegister src) {
241    Mfhc1(dst_high, src);
242  }
243
244  inline void FmoveLow(Register dst_low, FPURegister src) {
245    mfc1(dst_low, src);
246  }
247
248  inline void Move(FPURegister dst, Register src_low, Register src_high) {
249    mtc1(src_low, dst);
250    Mthc1(src_high, dst);
251  }
252
253  // Conditional move.
254  void Move(FPURegister dst, double imm);
255  void Movz(Register rd, Register rs, Register rt);
256  void Movn(Register rd, Register rs, Register rt);
257  void Movt(Register rd, Register rs, uint16_t cc = 0);
258  void Movf(Register rd, Register rs, uint16_t cc = 0);
259
260  void Clz(Register rd, Register rs);
261
262  // Jump unconditionally to given label.
263  // We NEED a nop in the branch delay slot, as it used by v8, for example in
264  // CodeGenerator::ProcessDeferred().
265  // Currently the branch delay slot is filled by the MacroAssembler.
266  // Use rather b(Label) for code generation.
267  void jmp(Label* L) {
268    Branch(L);
269  }
270
271  void Load(Register dst, const MemOperand& src, Representation r);
272  void Store(Register src, const MemOperand& dst, Representation r);
273
274  // Load an object from the root table.
275  void LoadRoot(Register destination,
276                Heap::RootListIndex index);
277  void LoadRoot(Register destination,
278                Heap::RootListIndex index,
279                Condition cond, Register src1, const Operand& src2);
280
281  // Store an object to the root table.
282  void StoreRoot(Register source,
283                 Heap::RootListIndex index);
284  void StoreRoot(Register source,
285                 Heap::RootListIndex index,
286                 Condition cond, Register src1, const Operand& src2);
287
288  // ---------------------------------------------------------------------------
289  // GC Support
290
291  void IncrementalMarkingRecordWriteHelper(Register object,
292                                           Register value,
293                                           Register address);
294
295  enum RememberedSetFinalAction {
296    kReturnAtEnd,
297    kFallThroughAtEnd
298  };
299
300
301  // Record in the remembered set the fact that we have a pointer to new space
302  // at the address pointed to by the addr register.  Only works if addr is not
303  // in new space.
304  void RememberedSetHelper(Register object,  // Used for debug code.
305                           Register addr,
306                           Register scratch,
307                           SaveFPRegsMode save_fp,
308                           RememberedSetFinalAction and_then);
309
310  void CheckPageFlag(Register object,
311                     Register scratch,
312                     int mask,
313                     Condition cc,
314                     Label* condition_met);
315
316  void CheckMapDeprecated(Handle<Map> map,
317                          Register scratch,
318                          Label* if_deprecated);
319
320  // Check if object is in new space.  Jumps if the object is not in new space.
321  // The register scratch can be object itself, but it will be clobbered.
322  void JumpIfNotInNewSpace(Register object,
323                           Register scratch,
324                           Label* branch) {
325    InNewSpace(object, scratch, ne, branch);
326  }
327
328  // Check if object is in new space.  Jumps if the object is in new space.
329  // The register scratch can be object itself, but scratch will be clobbered.
330  void JumpIfInNewSpace(Register object,
331                        Register scratch,
332                        Label* branch) {
333    InNewSpace(object, scratch, eq, branch);
334  }
335
336  // Check if an object has a given incremental marking color.
337  void HasColor(Register object,
338                Register scratch0,
339                Register scratch1,
340                Label* has_color,
341                int first_bit,
342                int second_bit);
343
344  void JumpIfBlack(Register object,
345                   Register scratch0,
346                   Register scratch1,
347                   Label* on_black);
348
349  // Checks the color of an object.  If the object is already grey or black
350  // then we just fall through, since it is already live.  If it is white and
351  // we can determine that it doesn't need to be scanned, then we just mark it
352  // black and fall through.  For the rest we jump to the label so the
353  // incremental marker can fix its assumptions.
354  void EnsureNotWhite(Register object,
355                      Register scratch1,
356                      Register scratch2,
357                      Register scratch3,
358                      Label* object_is_white_and_not_data);
359
360  // Detects conservatively whether an object is data-only, i.e. it does need to
361  // be scanned by the garbage collector.
362  void JumpIfDataObject(Register value,
363                        Register scratch,
364                        Label* not_data_object);
365
366  // Notify the garbage collector that we wrote a pointer into an object.
367  // |object| is the object being stored into, |value| is the object being
368  // stored.  value and scratch registers are clobbered by the operation.
369  // The offset is the offset from the start of the object, not the offset from
370  // the tagged HeapObject pointer.  For use with FieldOperand(reg, off).
371  void RecordWriteField(
372      Register object,
373      int offset,
374      Register value,
375      Register scratch,
376      RAStatus ra_status,
377      SaveFPRegsMode save_fp,
378      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
379      SmiCheck smi_check = INLINE_SMI_CHECK,
380      PointersToHereCheck pointers_to_here_check_for_value =
381          kPointersToHereMaybeInteresting);
382
383  // As above, but the offset has the tag presubtracted.  For use with
384  // MemOperand(reg, off).
385  inline void RecordWriteContextSlot(
386      Register context,
387      int offset,
388      Register value,
389      Register scratch,
390      RAStatus ra_status,
391      SaveFPRegsMode save_fp,
392      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
393      SmiCheck smi_check = INLINE_SMI_CHECK,
394      PointersToHereCheck pointers_to_here_check_for_value =
395          kPointersToHereMaybeInteresting) {
396    RecordWriteField(context,
397                     offset + kHeapObjectTag,
398                     value,
399                     scratch,
400                     ra_status,
401                     save_fp,
402                     remembered_set_action,
403                     smi_check,
404                     pointers_to_here_check_for_value);
405  }
406
407  void RecordWriteForMap(
408      Register object,
409      Register map,
410      Register dst,
411      RAStatus ra_status,
412      SaveFPRegsMode save_fp);
413
414  // For a given |object| notify the garbage collector that the slot |address|
415  // has been written.  |value| is the object being stored. The value and
416  // address registers are clobbered by the operation.
417  void RecordWrite(
418      Register object,
419      Register address,
420      Register value,
421      RAStatus ra_status,
422      SaveFPRegsMode save_fp,
423      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
424      SmiCheck smi_check = INLINE_SMI_CHECK,
425      PointersToHereCheck pointers_to_here_check_for_value =
426          kPointersToHereMaybeInteresting);
427
428
429  // ---------------------------------------------------------------------------
430  // Inline caching support.
431
432  // Generate code for checking access rights - used for security checks
433  // on access to global objects across environments. The holder register
434  // is left untouched, whereas both scratch registers are clobbered.
435  void CheckAccessGlobalProxy(Register holder_reg,
436                              Register scratch,
437                              Label* miss);
438
439  void GetNumberHash(Register reg0, Register scratch);
440
441  void LoadFromNumberDictionary(Label* miss,
442                                Register elements,
443                                Register key,
444                                Register result,
445                                Register reg0,
446                                Register reg1,
447                                Register reg2);
448
449
450  inline void MarkCode(NopMarkerTypes type) {
451    nop(type);
452  }
453
454  // Check if the given instruction is a 'type' marker.
455  // i.e. check if it is a sll zero_reg, zero_reg, <type> (referenced as
456  // nop(type)). These instructions are generated to mark special location in
457  // the code, like some special IC code.
458  static inline bool IsMarkedCode(Instr instr, int type) {
459    DCHECK((FIRST_IC_MARKER <= type) && (type < LAST_CODE_MARKER));
460    return IsNop(instr, type);
461  }
462
463
464  static inline int GetCodeMarker(Instr instr) {
465    uint32_t opcode = ((instr & kOpcodeMask));
466    uint32_t rt = ((instr & kRtFieldMask) >> kRtShift);
467    uint32_t rs = ((instr & kRsFieldMask) >> kRsShift);
468    uint32_t sa = ((instr & kSaFieldMask) >> kSaShift);
469
470    // Return <n> if we have a sll zero_reg, zero_reg, n
471    // else return -1.
472    bool sllzz = (opcode == SLL &&
473                  rt == static_cast<uint32_t>(ToNumber(zero_reg)) &&
474                  rs == static_cast<uint32_t>(ToNumber(zero_reg)));
475    int type =
476        (sllzz && FIRST_IC_MARKER <= sa && sa < LAST_CODE_MARKER) ? sa : -1;
477    DCHECK((type == -1) ||
478           ((FIRST_IC_MARKER <= type) && (type < LAST_CODE_MARKER)));
479    return type;
480  }
481
482
483
484  // ---------------------------------------------------------------------------
485  // Allocation support.
486
487  // Allocate an object in new space or old pointer space. The object_size is
488  // specified either in bytes or in words if the allocation flag SIZE_IN_WORDS
489  // is passed. If the space is exhausted control continues at the gc_required
490  // label. The allocated object is returned in result. If the flag
491  // tag_allocated_object is true the result is tagged as as a heap object.
492  // All registers are clobbered also when control continues at the gc_required
493  // label.
494  void Allocate(int object_size,
495                Register result,
496                Register scratch1,
497                Register scratch2,
498                Label* gc_required,
499                AllocationFlags flags);
500
501  void Allocate(Register object_size,
502                Register result,
503                Register scratch1,
504                Register scratch2,
505                Label* gc_required,
506                AllocationFlags flags);
507
508  // Undo allocation in new space. The object passed and objects allocated after
509  // it will no longer be allocated. The caller must make sure that no pointers
510  // are left to the object(s) no longer allocated as they would be invalid when
511  // allocation is undone.
512  void UndoAllocationInNewSpace(Register object, Register scratch);
513
514
515  void AllocateTwoByteString(Register result,
516                             Register length,
517                             Register scratch1,
518                             Register scratch2,
519                             Register scratch3,
520                             Label* gc_required);
521  void AllocateOneByteString(Register result, Register length,
522                             Register scratch1, Register scratch2,
523                             Register scratch3, Label* gc_required);
524  void AllocateTwoByteConsString(Register result,
525                                 Register length,
526                                 Register scratch1,
527                                 Register scratch2,
528                                 Label* gc_required);
529  void AllocateOneByteConsString(Register result, Register length,
530                                 Register scratch1, Register scratch2,
531                                 Label* gc_required);
532  void AllocateTwoByteSlicedString(Register result,
533                                   Register length,
534                                   Register scratch1,
535                                   Register scratch2,
536                                   Label* gc_required);
537  void AllocateOneByteSlicedString(Register result, Register length,
538                                   Register scratch1, Register scratch2,
539                                   Label* gc_required);
540
541  // Allocates a heap number or jumps to the gc_required label if the young
542  // space is full and a scavenge is needed. All registers are clobbered also
543  // when control continues at the gc_required label.
544  void AllocateHeapNumber(Register result,
545                          Register scratch1,
546                          Register scratch2,
547                          Register heap_number_map,
548                          Label* gc_required,
549                          TaggingMode tagging_mode = TAG_RESULT,
550                          MutableMode mode = IMMUTABLE);
551  void AllocateHeapNumberWithValue(Register result,
552                                   FPURegister value,
553                                   Register scratch1,
554                                   Register scratch2,
555                                   Label* gc_required);
556
557  // ---------------------------------------------------------------------------
558  // Instruction macros.
559
560#define DEFINE_INSTRUCTION(instr)                                              \
561  void instr(Register rd, Register rs, const Operand& rt);                     \
562  void instr(Register rd, Register rs, Register rt) {                          \
563    instr(rd, rs, Operand(rt));                                                \
564  }                                                                            \
565  void instr(Register rs, Register rt, int32_t j) {                            \
566    instr(rs, rt, Operand(j));                                                 \
567  }
568
569#define DEFINE_INSTRUCTION2(instr)                                             \
570  void instr(Register rs, const Operand& rt);                                  \
571  void instr(Register rs, Register rt) {                                       \
572    instr(rs, Operand(rt));                                                    \
573  }                                                                            \
574  void instr(Register rs, int32_t j) {                                         \
575    instr(rs, Operand(j));                                                     \
576  }
577
578#define DEFINE_INSTRUCTION3(instr)                                             \
579  void instr(Register rd_hi, Register rd_lo, Register rs, const Operand& rt);  \
580  void instr(Register rd_hi, Register rd_lo, Register rs, Register rt) {       \
581    instr(rd_hi, rd_lo, rs, Operand(rt));                                      \
582  }                                                                            \
583  void instr(Register rd_hi, Register rd_lo, Register rs, int32_t j) {         \
584    instr(rd_hi, rd_lo, rs, Operand(j));                                       \
585  }
586
587  DEFINE_INSTRUCTION(Addu);
588  DEFINE_INSTRUCTION(Subu);
589  DEFINE_INSTRUCTION(Mul);
590  DEFINE_INSTRUCTION(Mod);
591  DEFINE_INSTRUCTION(Mulh);
592  DEFINE_INSTRUCTION2(Mult);
593  DEFINE_INSTRUCTION2(Multu);
594  DEFINE_INSTRUCTION2(Div);
595  DEFINE_INSTRUCTION2(Divu);
596
597  DEFINE_INSTRUCTION3(Div);
598  DEFINE_INSTRUCTION3(Mul);
599
600  DEFINE_INSTRUCTION(And);
601  DEFINE_INSTRUCTION(Or);
602  DEFINE_INSTRUCTION(Xor);
603  DEFINE_INSTRUCTION(Nor);
604  DEFINE_INSTRUCTION2(Neg);
605
606  DEFINE_INSTRUCTION(Slt);
607  DEFINE_INSTRUCTION(Sltu);
608
609  // MIPS32 R2 instruction macro.
610  DEFINE_INSTRUCTION(Ror);
611
612#undef DEFINE_INSTRUCTION
613#undef DEFINE_INSTRUCTION2
614
615  void Pref(int32_t hint, const MemOperand& rs);
616
617
618  // ---------------------------------------------------------------------------
619  // Pseudo-instructions.
620
621  void mov(Register rd, Register rt) { or_(rd, rt, zero_reg); }
622
623  void Ulw(Register rd, const MemOperand& rs);
624  void Usw(Register rd, const MemOperand& rs);
625
626  // Load int32 in the rd register.
627  void li(Register rd, Operand j, LiFlags mode = OPTIMIZE_SIZE);
628  inline void li(Register rd, int32_t j, LiFlags mode = OPTIMIZE_SIZE) {
629    li(rd, Operand(j), mode);
630  }
631  void li(Register dst, Handle<Object> value, LiFlags mode = OPTIMIZE_SIZE);
632
633  // Push multiple registers on the stack.
634  // Registers are saved in numerical order, with higher numbered registers
635  // saved in higher memory addresses.
636  void MultiPush(RegList regs);
637  void MultiPushReversed(RegList regs);
638
639  void MultiPushFPU(RegList regs);
640  void MultiPushReversedFPU(RegList regs);
641
642  void push(Register src) {
643    Addu(sp, sp, Operand(-kPointerSize));
644    sw(src, MemOperand(sp, 0));
645  }
646  void Push(Register src) { push(src); }
647
648  // Push a handle.
649  void Push(Handle<Object> handle);
650  void Push(Smi* smi) { Push(Handle<Smi>(smi, isolate())); }
651
652  // Push two registers. Pushes leftmost register first (to highest address).
653  void Push(Register src1, Register src2) {
654    Subu(sp, sp, Operand(2 * kPointerSize));
655    sw(src1, MemOperand(sp, 1 * kPointerSize));
656    sw(src2, MemOperand(sp, 0 * kPointerSize));
657  }
658
659  // Push three registers. Pushes leftmost register first (to highest address).
660  void Push(Register src1, Register src2, Register src3) {
661    Subu(sp, sp, Operand(3 * kPointerSize));
662    sw(src1, MemOperand(sp, 2 * kPointerSize));
663    sw(src2, MemOperand(sp, 1 * kPointerSize));
664    sw(src3, MemOperand(sp, 0 * kPointerSize));
665  }
666
667  // Push four registers. Pushes leftmost register first (to highest address).
668  void Push(Register src1, Register src2, Register src3, Register src4) {
669    Subu(sp, sp, Operand(4 * kPointerSize));
670    sw(src1, MemOperand(sp, 3 * kPointerSize));
671    sw(src2, MemOperand(sp, 2 * kPointerSize));
672    sw(src3, MemOperand(sp, 1 * kPointerSize));
673    sw(src4, MemOperand(sp, 0 * kPointerSize));
674  }
675
676  void Push(Register src, Condition cond, Register tst1, Register tst2) {
677    // Since we don't have conditional execution we use a Branch.
678    Branch(3, cond, tst1, Operand(tst2));
679    Subu(sp, sp, Operand(kPointerSize));
680    sw(src, MemOperand(sp, 0));
681  }
682
683  // Pops multiple values from the stack and load them in the
684  // registers specified in regs. Pop order is the opposite as in MultiPush.
685  void MultiPop(RegList regs);
686  void MultiPopReversed(RegList regs);
687
688  void MultiPopFPU(RegList regs);
689  void MultiPopReversedFPU(RegList regs);
690
691  void pop(Register dst) {
692    lw(dst, MemOperand(sp, 0));
693    Addu(sp, sp, Operand(kPointerSize));
694  }
695  void Pop(Register dst) { pop(dst); }
696
697  // Pop two registers. Pops rightmost register first (from lower address).
698  void Pop(Register src1, Register src2) {
699    DCHECK(!src1.is(src2));
700    lw(src2, MemOperand(sp, 0 * kPointerSize));
701    lw(src1, MemOperand(sp, 1 * kPointerSize));
702    Addu(sp, sp, 2 * kPointerSize);
703  }
704
705  // Pop three registers. Pops rightmost register first (from lower address).
706  void Pop(Register src1, Register src2, Register src3) {
707    lw(src3, MemOperand(sp, 0 * kPointerSize));
708    lw(src2, MemOperand(sp, 1 * kPointerSize));
709    lw(src1, MemOperand(sp, 2 * kPointerSize));
710    Addu(sp, sp, 3 * kPointerSize);
711  }
712
713  void Pop(uint32_t count = 1) {
714    Addu(sp, sp, Operand(count * kPointerSize));
715  }
716
717  // Push and pop the registers that can hold pointers, as defined by the
718  // RegList constant kSafepointSavedRegisters.
719  void PushSafepointRegisters();
720  void PopSafepointRegisters();
721  // Store value in register src in the safepoint stack slot for
722  // register dst.
723  void StoreToSafepointRegisterSlot(Register src, Register dst);
724  // Load the value of the src register from its safepoint stack slot
725  // into register dst.
726  void LoadFromSafepointRegisterSlot(Register dst, Register src);
727
728  // Flush the I-cache from asm code. You should use CpuFeatures::FlushICache
729  // from C.
730  // Does not handle errors.
731  void FlushICache(Register address, unsigned instructions);
732
733  // MIPS32 R2 instruction macro.
734  void Ins(Register rt, Register rs, uint16_t pos, uint16_t size);
735  void Ext(Register rt, Register rs, uint16_t pos, uint16_t size);
736
737  // ---------------------------------------------------------------------------
738  // FPU macros. These do not handle special cases like NaN or +- inf.
739
740  // Convert unsigned word to double.
741  void Cvt_d_uw(FPURegister fd, FPURegister fs, FPURegister scratch);
742  void Cvt_d_uw(FPURegister fd, Register rs, FPURegister scratch);
743
744  // Convert double to unsigned word.
745  void Trunc_uw_d(FPURegister fd, FPURegister fs, FPURegister scratch);
746  void Trunc_uw_d(FPURegister fd, Register rs, FPURegister scratch);
747
748  void Trunc_w_d(FPURegister fd, FPURegister fs);
749  void Round_w_d(FPURegister fd, FPURegister fs);
750  void Floor_w_d(FPURegister fd, FPURegister fs);
751  void Ceil_w_d(FPURegister fd, FPURegister fs);
752
753  // FP32 mode: Move the general purpose register into
754  // the high part of the double-register pair.
755  // FP64 mode: Move the general-purpose register into
756  // the higher 32 bits of the 64-bit coprocessor register,
757  // while leaving the low bits unchanged.
758  void Mthc1(Register rt, FPURegister fs);
759
760  // FP32 mode: move the high part of the double-register pair into
761  // general purpose register.
762  // FP64 mode: Move the higher 32 bits of the 64-bit coprocessor register into
763  // general-purpose register.
764  void Mfhc1(Register rt, FPURegister fs);
765
766  // Wrapper function for the different cmp/branch types.
767  void BranchF(Label* target,
768               Label* nan,
769               Condition cc,
770               FPURegister cmp1,
771               FPURegister cmp2,
772               BranchDelaySlot bd = PROTECT);
773
774  // Alternate (inline) version for better readability with USE_DELAY_SLOT.
775  inline void BranchF(BranchDelaySlot bd,
776                      Label* target,
777                      Label* nan,
778                      Condition cc,
779                      FPURegister cmp1,
780                      FPURegister cmp2) {
781    BranchF(target, nan, cc, cmp1, cmp2, bd);
782  }
783
784  // Truncates a double using a specific rounding mode, and writes the value
785  // to the result register.
786  // The except_flag will contain any exceptions caused by the instruction.
787  // If check_inexact is kDontCheckForInexactConversion, then the inexact
788  // exception is masked.
789  void EmitFPUTruncate(FPURoundingMode rounding_mode,
790                       Register result,
791                       DoubleRegister double_input,
792                       Register scratch,
793                       DoubleRegister double_scratch,
794                       Register except_flag,
795                       CheckForInexactConversion check_inexact
796                           = kDontCheckForInexactConversion);
797
798  // Performs a truncating conversion of a floating point number as used by
799  // the JS bitwise operations. See ECMA-262 9.5: ToInt32. Goes to 'done' if it
800  // succeeds, otherwise falls through if result is saturated. On return
801  // 'result' either holds answer, or is clobbered on fall through.
802  //
803  // Only public for the test code in test-code-stubs-arm.cc.
804  void TryInlineTruncateDoubleToI(Register result,
805                                  DoubleRegister input,
806                                  Label* done);
807
808  // Performs a truncating conversion of a floating point number as used by
809  // the JS bitwise operations. See ECMA-262 9.5: ToInt32.
810  // Exits with 'result' holding the answer.
811  void TruncateDoubleToI(Register result, DoubleRegister double_input);
812
813  // Performs a truncating conversion of a heap number as used by
814  // the JS bitwise operations. See ECMA-262 9.5: ToInt32. 'result' and 'input'
815  // must be different registers. Exits with 'result' holding the answer.
816  void TruncateHeapNumberToI(Register result, Register object);
817
818  // Converts the smi or heap number in object to an int32 using the rules
819  // for ToInt32 as described in ECMAScript 9.5.: the value is truncated
820  // and brought into the range -2^31 .. +2^31 - 1. 'result' and 'input' must be
821  // different registers.
822  void TruncateNumberToI(Register object,
823                         Register result,
824                         Register heap_number_map,
825                         Register scratch,
826                         Label* not_int32);
827
828  // Loads the number from object into dst register.
829  // If |object| is neither smi nor heap number, |not_number| is jumped to
830  // with |object| still intact.
831  void LoadNumber(Register object,
832                  FPURegister dst,
833                  Register heap_number_map,
834                  Register scratch,
835                  Label* not_number);
836
837  // Loads the number from object into double_dst in the double format.
838  // Control will jump to not_int32 if the value cannot be exactly represented
839  // by a 32-bit integer.
840  // Floating point value in the 32-bit integer range that are not exact integer
841  // won't be loaded.
842  void LoadNumberAsInt32Double(Register object,
843                               DoubleRegister double_dst,
844                               Register heap_number_map,
845                               Register scratch1,
846                               Register scratch2,
847                               FPURegister double_scratch,
848                               Label* not_int32);
849
850  // Loads the number from object into dst as a 32-bit integer.
851  // Control will jump to not_int32 if the object cannot be exactly represented
852  // by a 32-bit integer.
853  // Floating point value in the 32-bit integer range that are not exact integer
854  // won't be converted.
855  void LoadNumberAsInt32(Register object,
856                         Register dst,
857                         Register heap_number_map,
858                         Register scratch1,
859                         Register scratch2,
860                         FPURegister double_scratch0,
861                         FPURegister double_scratch1,
862                         Label* not_int32);
863
864  // Enter exit frame.
865  // argc - argument count to be dropped by LeaveExitFrame.
866  // save_doubles - saves FPU registers on stack, currently disabled.
867  // stack_space - extra stack space.
868  void EnterExitFrame(bool save_doubles,
869                      int stack_space = 0);
870
871  // Leave the current exit frame.
872  void LeaveExitFrame(bool save_doubles,
873                      Register arg_count,
874                      bool restore_context,
875                      bool do_return = NO_EMIT_RETURN);
876
877  // Get the actual activation frame alignment for target environment.
878  static int ActivationFrameAlignment();
879
880  // Make sure the stack is aligned. Only emits code in debug mode.
881  void AssertStackIsAligned();
882
883  void LoadContext(Register dst, int context_chain_length);
884
885  // Conditionally load the cached Array transitioned map of type
886  // transitioned_kind from the native context if the map in register
887  // map_in_out is the cached Array map in the native context of
888  // expected_kind.
889  void LoadTransitionedArrayMapConditional(
890      ElementsKind expected_kind,
891      ElementsKind transitioned_kind,
892      Register map_in_out,
893      Register scratch,
894      Label* no_map_match);
895
896  void LoadGlobalFunction(int index, Register function);
897
898  // Load the initial map from the global function. The registers
899  // function and map can be the same, function is then overwritten.
900  void LoadGlobalFunctionInitialMap(Register function,
901                                    Register map,
902                                    Register scratch);
903
904  void InitializeRootRegister() {
905    ExternalReference roots_array_start =
906        ExternalReference::roots_array_start(isolate());
907    li(kRootRegister, Operand(roots_array_start));
908  }
909
910  // -------------------------------------------------------------------------
911  // JavaScript invokes.
912
913  // Invoke the JavaScript function code by either calling or jumping.
914  void InvokeCode(Register code,
915                  const ParameterCount& expected,
916                  const ParameterCount& actual,
917                  InvokeFlag flag,
918                  const CallWrapper& call_wrapper);
919
920  // Invoke the JavaScript function in the given register. Changes the
921  // current context to the context in the function before invoking.
922  void InvokeFunction(Register function,
923                      const ParameterCount& actual,
924                      InvokeFlag flag,
925                      const CallWrapper& call_wrapper);
926
927  void InvokeFunction(Register function,
928                      const ParameterCount& expected,
929                      const ParameterCount& actual,
930                      InvokeFlag flag,
931                      const CallWrapper& call_wrapper);
932
933  void InvokeFunction(Handle<JSFunction> function,
934                      const ParameterCount& expected,
935                      const ParameterCount& actual,
936                      InvokeFlag flag,
937                      const CallWrapper& call_wrapper);
938
939
940  void IsObjectJSObjectType(Register heap_object,
941                            Register map,
942                            Register scratch,
943                            Label* fail);
944
945  void IsInstanceJSObjectType(Register map,
946                              Register scratch,
947                              Label* fail);
948
949  void IsObjectJSStringType(Register object,
950                            Register scratch,
951                            Label* fail);
952
953  void IsObjectNameType(Register object,
954                        Register scratch,
955                        Label* fail);
956
957  // -------------------------------------------------------------------------
958  // Debugger Support.
959
960  void DebugBreak();
961
962  // -------------------------------------------------------------------------
963  // Exception handling.
964
965  // Push a new try handler and link into try handler chain.
966  void PushTryHandler(StackHandler::Kind kind, int handler_index);
967
968  // Unlink the stack handler on top of the stack from the try handler chain.
969  // Must preserve the result register.
970  void PopTryHandler();
971
972  // Passes thrown value to the handler of top of the try handler chain.
973  void Throw(Register value);
974
975  // Propagates an uncatchable exception to the top of the current JS stack's
976  // handler chain.
977  void ThrowUncatchable(Register value);
978
979  // Copies a fixed number of fields of heap objects from src to dst.
980  void CopyFields(Register dst, Register src, RegList temps, int field_count);
981
982  // Copies a number of bytes from src to dst. All registers are clobbered. On
983  // exit src and dst will point to the place just after where the last byte was
984  // read or written and length will be zero.
985  void CopyBytes(Register src,
986                 Register dst,
987                 Register length,
988                 Register scratch);
989
990  // Initialize fields with filler values.  Fields starting at |start_offset|
991  // not including end_offset are overwritten with the value in |filler|.  At
992  // the end the loop, |start_offset| takes the value of |end_offset|.
993  void InitializeFieldsWithFiller(Register start_offset,
994                                  Register end_offset,
995                                  Register filler);
996
997  // -------------------------------------------------------------------------
998  // Support functions.
999
1000  // Try to get function prototype of a function and puts the value in
1001  // the result register. Checks that the function really is a
1002  // function and jumps to the miss label if the fast checks fail. The
1003  // function register will be untouched; the other registers may be
1004  // clobbered.
1005  void TryGetFunctionPrototype(Register function,
1006                               Register result,
1007                               Register scratch,
1008                               Label* miss,
1009                               bool miss_on_bound_function = false);
1010
1011  void GetObjectType(Register function,
1012                     Register map,
1013                     Register type_reg);
1014
1015  // Check if a map for a JSObject indicates that the object has fast elements.
1016  // Jump to the specified label if it does not.
1017  void CheckFastElements(Register map,
1018                         Register scratch,
1019                         Label* fail);
1020
1021  // Check if a map for a JSObject indicates that the object can have both smi
1022  // and HeapObject elements.  Jump to the specified label if it does not.
1023  void CheckFastObjectElements(Register map,
1024                               Register scratch,
1025                               Label* fail);
1026
1027  // Check if a map for a JSObject indicates that the object has fast smi only
1028  // elements.  Jump to the specified label if it does not.
1029  void CheckFastSmiElements(Register map,
1030                            Register scratch,
1031                            Label* fail);
1032
1033  // Check to see if maybe_number can be stored as a double in
1034  // FastDoubleElements. If it can, store it at the index specified by key in
1035  // the FastDoubleElements array elements. Otherwise jump to fail.
1036  void StoreNumberToDoubleElements(Register value_reg,
1037                                   Register key_reg,
1038                                   Register elements_reg,
1039                                   Register scratch1,
1040                                   Register scratch2,
1041                                   Register scratch3,
1042                                   Label* fail,
1043                                   int elements_offset = 0);
1044
1045  // Compare an object's map with the specified map and its transitioned
1046  // elements maps if mode is ALLOW_ELEMENT_TRANSITION_MAPS. Jumps to
1047  // "branch_to" if the result of the comparison is "cond". If multiple map
1048  // compares are required, the compare sequences branches to early_success.
1049  void CompareMapAndBranch(Register obj,
1050                           Register scratch,
1051                           Handle<Map> map,
1052                           Label* early_success,
1053                           Condition cond,
1054                           Label* branch_to);
1055
1056  // As above, but the map of the object is already loaded into the register
1057  // which is preserved by the code generated.
1058  void CompareMapAndBranch(Register obj_map,
1059                           Handle<Map> map,
1060                           Label* early_success,
1061                           Condition cond,
1062                           Label* branch_to);
1063
1064  // Check if the map of an object is equal to a specified map and branch to
1065  // label if not. Skip the smi check if not required (object is known to be a
1066  // heap object). If mode is ALLOW_ELEMENT_TRANSITION_MAPS, then also match
1067  // against maps that are ElementsKind transition maps of the specificed map.
1068  void CheckMap(Register obj,
1069                Register scratch,
1070                Handle<Map> map,
1071                Label* fail,
1072                SmiCheckType smi_check_type);
1073
1074
1075  void CheckMap(Register obj,
1076                Register scratch,
1077                Heap::RootListIndex index,
1078                Label* fail,
1079                SmiCheckType smi_check_type);
1080
1081  // Check if the map of an object is equal to a specified map and branch to a
1082  // specified target if equal. Skip the smi check if not required (object is
1083  // known to be a heap object)
1084  void DispatchMap(Register obj,
1085                   Register scratch,
1086                   Handle<Map> map,
1087                   Handle<Code> success,
1088                   SmiCheckType smi_check_type);
1089
1090
1091  // Load and check the instance type of an object for being a string.
1092  // Loads the type into the second argument register.
1093  // Returns a condition that will be enabled if the object was a string.
1094  Condition IsObjectStringType(Register obj,
1095                               Register type,
1096                               Register result) {
1097    lw(type, FieldMemOperand(obj, HeapObject::kMapOffset));
1098    lbu(type, FieldMemOperand(type, Map::kInstanceTypeOffset));
1099    And(type, type, Operand(kIsNotStringMask));
1100    DCHECK_EQ(0, kStringTag);
1101    return eq;
1102  }
1103
1104
1105  // Picks out an array index from the hash field.
1106  // Register use:
1107  //   hash - holds the index's hash. Clobbered.
1108  //   index - holds the overwritten index on exit.
1109  void IndexFromHash(Register hash, Register index);
1110
1111  // Get the number of least significant bits from a register.
1112  void GetLeastBitsFromSmi(Register dst, Register src, int num_least_bits);
1113  void GetLeastBitsFromInt32(Register dst, Register src, int mun_least_bits);
1114
1115  // Load the value of a number object into a FPU double register. If the
1116  // object is not a number a jump to the label not_number is performed
1117  // and the FPU double register is unchanged.
1118  void ObjectToDoubleFPURegister(
1119      Register object,
1120      FPURegister value,
1121      Register scratch1,
1122      Register scratch2,
1123      Register heap_number_map,
1124      Label* not_number,
1125      ObjectToDoubleFlags flags = NO_OBJECT_TO_DOUBLE_FLAGS);
1126
1127  // Load the value of a smi object into a FPU double register. The register
1128  // scratch1 can be the same register as smi in which case smi will hold the
1129  // untagged value afterwards.
1130  void SmiToDoubleFPURegister(Register smi,
1131                              FPURegister value,
1132                              Register scratch1);
1133
1134  // -------------------------------------------------------------------------
1135  // Overflow handling functions.
1136  // Usage: first call the appropriate arithmetic function, then call one of the
1137  // jump functions with the overflow_dst register as the second parameter.
1138
1139  void AdduAndCheckForOverflow(Register dst,
1140                               Register left,
1141                               Register right,
1142                               Register overflow_dst,
1143                               Register scratch = at);
1144
1145  void SubuAndCheckForOverflow(Register dst,
1146                               Register left,
1147                               Register right,
1148                               Register overflow_dst,
1149                               Register scratch = at);
1150
1151  void BranchOnOverflow(Label* label,
1152                        Register overflow_check,
1153                        BranchDelaySlot bd = PROTECT) {
1154    Branch(label, lt, overflow_check, Operand(zero_reg), bd);
1155  }
1156
1157  void BranchOnNoOverflow(Label* label,
1158                          Register overflow_check,
1159                          BranchDelaySlot bd = PROTECT) {
1160    Branch(label, ge, overflow_check, Operand(zero_reg), bd);
1161  }
1162
1163  void RetOnOverflow(Register overflow_check, BranchDelaySlot bd = PROTECT) {
1164    Ret(lt, overflow_check, Operand(zero_reg), bd);
1165  }
1166
1167  void RetOnNoOverflow(Register overflow_check, BranchDelaySlot bd = PROTECT) {
1168    Ret(ge, overflow_check, Operand(zero_reg), bd);
1169  }
1170
1171  // -------------------------------------------------------------------------
1172  // Runtime calls.
1173
1174  // See comments at the beginning of CEntryStub::Generate.
1175  inline void PrepareCEntryArgs(int num_args) {
1176    li(s0, num_args);
1177    li(s1, (num_args - 1) * kPointerSize);
1178  }
1179
1180  inline void PrepareCEntryFunction(const ExternalReference& ref) {
1181    li(s2, Operand(ref));
1182  }
1183
1184#define COND_ARGS Condition cond = al, Register rs = zero_reg, \
1185const Operand& rt = Operand(zero_reg), BranchDelaySlot bd = PROTECT
1186
1187  // Call a code stub.
1188  void CallStub(CodeStub* stub,
1189                TypeFeedbackId ast_id = TypeFeedbackId::None(),
1190                COND_ARGS);
1191
1192  // Tail call a code stub (jump).
1193  void TailCallStub(CodeStub* stub, COND_ARGS);
1194
1195#undef COND_ARGS
1196
1197  void CallJSExitStub(CodeStub* stub);
1198
1199  // Call a runtime routine.
1200  void CallRuntime(const Runtime::Function* f,
1201                   int num_arguments,
1202                   SaveFPRegsMode save_doubles = kDontSaveFPRegs);
1203  void CallRuntimeSaveDoubles(Runtime::FunctionId id) {
1204    const Runtime::Function* function = Runtime::FunctionForId(id);
1205    CallRuntime(function, function->nargs, kSaveFPRegs);
1206  }
1207
1208  // Convenience function: Same as above, but takes the fid instead.
1209  void CallRuntime(Runtime::FunctionId id,
1210                   int num_arguments,
1211                   SaveFPRegsMode save_doubles = kDontSaveFPRegs) {
1212    CallRuntime(Runtime::FunctionForId(id), num_arguments, save_doubles);
1213  }
1214
1215  // Convenience function: call an external reference.
1216  void CallExternalReference(const ExternalReference& ext,
1217                             int num_arguments,
1218                             BranchDelaySlot bd = PROTECT);
1219
1220  // Tail call of a runtime routine (jump).
1221  // Like JumpToExternalReference, but also takes care of passing the number
1222  // of parameters.
1223  void TailCallExternalReference(const ExternalReference& ext,
1224                                 int num_arguments,
1225                                 int result_size);
1226
1227  // Convenience function: tail call a runtime routine (jump).
1228  void TailCallRuntime(Runtime::FunctionId fid,
1229                       int num_arguments,
1230                       int result_size);
1231
1232  int CalculateStackPassedWords(int num_reg_arguments,
1233                                int num_double_arguments);
1234
1235  // Before calling a C-function from generated code, align arguments on stack
1236  // and add space for the four mips argument slots.
1237  // After aligning the frame, non-register arguments must be stored on the
1238  // stack, after the argument-slots using helper: CFunctionArgumentOperand().
1239  // The argument count assumes all arguments are word sized.
1240  // Some compilers/platforms require the stack to be aligned when calling
1241  // C++ code.
1242  // Needs a scratch register to do some arithmetic. This register will be
1243  // trashed.
1244  void PrepareCallCFunction(int num_reg_arguments,
1245                            int num_double_registers,
1246                            Register scratch);
1247  void PrepareCallCFunction(int num_reg_arguments,
1248                            Register scratch);
1249
1250  // Arguments 1-4 are placed in registers a0 thru a3 respectively.
1251  // Arguments 5..n are stored to stack using following:
1252  //  sw(t0, CFunctionArgumentOperand(5));
1253
1254  // Calls a C function and cleans up the space for arguments allocated
1255  // by PrepareCallCFunction. The called function is not allowed to trigger a
1256  // garbage collection, since that might move the code and invalidate the
1257  // return address (unless this is somehow accounted for by the called
1258  // function).
1259  void CallCFunction(ExternalReference function, int num_arguments);
1260  void CallCFunction(Register function, int num_arguments);
1261  void CallCFunction(ExternalReference function,
1262                     int num_reg_arguments,
1263                     int num_double_arguments);
1264  void CallCFunction(Register function,
1265                     int num_reg_arguments,
1266                     int num_double_arguments);
1267  void MovFromFloatResult(DoubleRegister dst);
1268  void MovFromFloatParameter(DoubleRegister dst);
1269
1270  // There are two ways of passing double arguments on MIPS, depending on
1271  // whether soft or hard floating point ABI is used. These functions
1272  // abstract parameter passing for the three different ways we call
1273  // C functions from generated code.
1274  void MovToFloatParameter(DoubleRegister src);
1275  void MovToFloatParameters(DoubleRegister src1, DoubleRegister src2);
1276  void MovToFloatResult(DoubleRegister src);
1277
1278  // Calls an API function.  Allocates HandleScope, extracts returned value
1279  // from handle and propagates exceptions.  Restores context.  stack_space
1280  // - space to be unwound on exit (includes the call JS arguments space and
1281  // the additional space allocated for the fast call).
1282  void CallApiFunctionAndReturn(Register function_address,
1283                                ExternalReference thunk_ref,
1284                                int stack_space,
1285                                MemOperand return_value_operand,
1286                                MemOperand* context_restore_operand);
1287
1288  // Jump to the builtin routine.
1289  void JumpToExternalReference(const ExternalReference& builtin,
1290                               BranchDelaySlot bd = PROTECT);
1291
1292  // Invoke specified builtin JavaScript function. Adds an entry to
1293  // the unresolved list if the name does not resolve.
1294  void InvokeBuiltin(Builtins::JavaScript id,
1295                     InvokeFlag flag,
1296                     const CallWrapper& call_wrapper = NullCallWrapper());
1297
1298  // Store the code object for the given builtin in the target register and
1299  // setup the function in a1.
1300  void GetBuiltinEntry(Register target, Builtins::JavaScript id);
1301
1302  // Store the function for the given builtin in the target register.
1303  void GetBuiltinFunction(Register target, Builtins::JavaScript id);
1304
1305  struct Unresolved {
1306    int pc;
1307    uint32_t flags;  // See Bootstrapper::FixupFlags decoders/encoders.
1308    const char* name;
1309  };
1310
1311  Handle<Object> CodeObject() {
1312    DCHECK(!code_object_.is_null());
1313    return code_object_;
1314  }
1315
1316  // Emit code for a truncating division by a constant. The dividend register is
1317  // unchanged and at gets clobbered. Dividend and result must be different.
1318  void TruncatingDiv(Register result, Register dividend, int32_t divisor);
1319
1320  // -------------------------------------------------------------------------
1321  // StatsCounter support.
1322
1323  void SetCounter(StatsCounter* counter, int value,
1324                  Register scratch1, Register scratch2);
1325  void IncrementCounter(StatsCounter* counter, int value,
1326                        Register scratch1, Register scratch2);
1327  void DecrementCounter(StatsCounter* counter, int value,
1328                        Register scratch1, Register scratch2);
1329
1330
1331  // -------------------------------------------------------------------------
1332  // Debugging.
1333
1334  // Calls Abort(msg) if the condition cc is not satisfied.
1335  // Use --debug_code to enable.
1336  void Assert(Condition cc, BailoutReason reason, Register rs, Operand rt);
1337  void AssertFastElements(Register elements);
1338
1339  // Like Assert(), but always enabled.
1340  void Check(Condition cc, BailoutReason reason, Register rs, Operand rt);
1341
1342  // Print a message to stdout and abort execution.
1343  void Abort(BailoutReason msg);
1344
1345  // Verify restrictions about code generated in stubs.
1346  void set_generating_stub(bool value) { generating_stub_ = value; }
1347  bool generating_stub() { return generating_stub_; }
1348  void set_has_frame(bool value) { has_frame_ = value; }
1349  bool has_frame() { return has_frame_; }
1350  inline bool AllowThisStubCall(CodeStub* stub);
1351
1352  // ---------------------------------------------------------------------------
1353  // Number utilities.
1354
1355  // Check whether the value of reg is a power of two and not zero. If not
1356  // control continues at the label not_power_of_two. If reg is a power of two
1357  // the register scratch contains the value of (reg - 1) when control falls
1358  // through.
1359  void JumpIfNotPowerOfTwoOrZero(Register reg,
1360                                 Register scratch,
1361                                 Label* not_power_of_two_or_zero);
1362
1363  // -------------------------------------------------------------------------
1364  // Smi utilities.
1365
1366  void SmiTag(Register reg) {
1367    Addu(reg, reg, reg);
1368  }
1369
1370  // Test for overflow < 0: use BranchOnOverflow() or BranchOnNoOverflow().
1371  void SmiTagCheckOverflow(Register reg, Register overflow);
1372  void SmiTagCheckOverflow(Register dst, Register src, Register overflow);
1373
1374  void SmiTag(Register dst, Register src) {
1375    Addu(dst, src, src);
1376  }
1377
1378  // Try to convert int32 to smi. If the value is to large, preserve
1379  // the original value and jump to not_a_smi. Destroys scratch and
1380  // sets flags.
1381  void TrySmiTag(Register reg, Register scratch, Label* not_a_smi) {
1382    TrySmiTag(reg, reg, scratch, not_a_smi);
1383  }
1384  void TrySmiTag(Register dst,
1385                 Register src,
1386                 Register scratch,
1387                 Label* not_a_smi) {
1388    SmiTagCheckOverflow(at, src, scratch);
1389    BranchOnOverflow(not_a_smi, scratch);
1390    mov(dst, at);
1391  }
1392
1393  void SmiUntag(Register reg) {
1394    sra(reg, reg, kSmiTagSize);
1395  }
1396
1397  void SmiUntag(Register dst, Register src) {
1398    sra(dst, src, kSmiTagSize);
1399  }
1400
1401  // Test if the register contains a smi.
1402  inline void SmiTst(Register value, Register scratch) {
1403    And(scratch, value, Operand(kSmiTagMask));
1404  }
1405  inline void NonNegativeSmiTst(Register value, Register scratch) {
1406    And(scratch, value, Operand(kSmiTagMask | kSmiSignMask));
1407  }
1408
1409  // Untag the source value into destination and jump if source is a smi.
1410  // Souce and destination can be the same register.
1411  void UntagAndJumpIfSmi(Register dst, Register src, Label* smi_case);
1412
1413  // Untag the source value into destination and jump if source is not a smi.
1414  // Souce and destination can be the same register.
1415  void UntagAndJumpIfNotSmi(Register dst, Register src, Label* non_smi_case);
1416
1417  // Jump the register contains a smi.
1418  void JumpIfSmi(Register value,
1419                 Label* smi_label,
1420                 Register scratch = at,
1421                 BranchDelaySlot bd = PROTECT);
1422
1423  // Jump if the register contains a non-smi.
1424  void JumpIfNotSmi(Register value,
1425                    Label* not_smi_label,
1426                    Register scratch = at,
1427                    BranchDelaySlot bd = PROTECT);
1428
1429  // Jump if either of the registers contain a non-smi.
1430  void JumpIfNotBothSmi(Register reg1, Register reg2, Label* on_not_both_smi);
1431  // Jump if either of the registers contain a smi.
1432  void JumpIfEitherSmi(Register reg1, Register reg2, Label* on_either_smi);
1433
1434  // Abort execution if argument is a smi, enabled via --debug-code.
1435  void AssertNotSmi(Register object);
1436  void AssertSmi(Register object);
1437
1438  // Abort execution if argument is not a string, enabled via --debug-code.
1439  void AssertString(Register object);
1440
1441  // Abort execution if argument is not a name, enabled via --debug-code.
1442  void AssertName(Register object);
1443
1444  // Abort execution if argument is not undefined or an AllocationSite, enabled
1445  // via --debug-code.
1446  void AssertUndefinedOrAllocationSite(Register object, Register scratch);
1447
1448  // Abort execution if reg is not the root value with the given index,
1449  // enabled via --debug-code.
1450  void AssertIsRoot(Register reg, Heap::RootListIndex index);
1451
1452  // ---------------------------------------------------------------------------
1453  // HeapNumber utilities.
1454
1455  void JumpIfNotHeapNumber(Register object,
1456                           Register heap_number_map,
1457                           Register scratch,
1458                           Label* on_not_heap_number);
1459
1460  // -------------------------------------------------------------------------
1461  // String utilities.
1462
1463  // Generate code to do a lookup in the number string cache. If the number in
1464  // the register object is found in the cache the generated code falls through
1465  // with the result in the result register. The object and the result register
1466  // can be the same. If the number is not found in the cache the code jumps to
1467  // the label not_found with only the content of register object unchanged.
1468  void LookupNumberStringCache(Register object,
1469                               Register result,
1470                               Register scratch1,
1471                               Register scratch2,
1472                               Register scratch3,
1473                               Label* not_found);
1474
1475  // Checks if both instance types are sequential ASCII strings and jumps to
1476  // label if either is not.
1477  void JumpIfBothInstanceTypesAreNotSequentialOneByte(
1478      Register first_object_instance_type, Register second_object_instance_type,
1479      Register scratch1, Register scratch2, Label* failure);
1480
1481  // Check if instance type is sequential one-byte string and jump to label if
1482  // it is not.
1483  void JumpIfInstanceTypeIsNotSequentialOneByte(Register type, Register scratch,
1484                                                Label* failure);
1485
1486  void JumpIfNotUniqueNameInstanceType(Register reg, Label* not_unique_name);
1487
1488  void EmitSeqStringSetCharCheck(Register string,
1489                                 Register index,
1490                                 Register value,
1491                                 Register scratch,
1492                                 uint32_t encoding_mask);
1493
1494  // Checks if both objects are sequential one-byte strings and jumps to label
1495  // if either is not. Assumes that neither object is a smi.
1496  void JumpIfNonSmisNotBothSequentialOneByteStrings(Register first,
1497                                                    Register second,
1498                                                    Register scratch1,
1499                                                    Register scratch2,
1500                                                    Label* failure);
1501
1502  // Checks if both objects are sequential one-byte strings and jumps to label
1503  // if either is not.
1504  void JumpIfNotBothSequentialOneByteStrings(Register first, Register second,
1505                                             Register scratch1,
1506                                             Register scratch2,
1507                                             Label* not_flat_one_byte_strings);
1508
1509  void ClampUint8(Register output_reg, Register input_reg);
1510
1511  void ClampDoubleToUint8(Register result_reg,
1512                          DoubleRegister input_reg,
1513                          DoubleRegister temp_double_reg);
1514
1515
1516  void LoadInstanceDescriptors(Register map, Register descriptors);
1517  void EnumLength(Register dst, Register map);
1518  void NumberOfOwnDescriptors(Register dst, Register map);
1519
1520  template<typename Field>
1521  void DecodeField(Register dst, Register src) {
1522    Ext(dst, src, Field::kShift, Field::kSize);
1523  }
1524
1525  template<typename Field>
1526  void DecodeField(Register reg) {
1527    DecodeField<Field>(reg, reg);
1528  }
1529
1530  template<typename Field>
1531  void DecodeFieldToSmi(Register dst, Register src) {
1532    static const int shift = Field::kShift;
1533    static const int mask = Field::kMask >> shift << kSmiTagSize;
1534    STATIC_ASSERT((mask & (0x80000000u >> (kSmiTagSize - 1))) == 0);
1535    STATIC_ASSERT(kSmiTag == 0);
1536    if (shift < kSmiTagSize) {
1537      sll(dst, src, kSmiTagSize - shift);
1538      And(dst, dst, Operand(mask));
1539    } else if (shift > kSmiTagSize) {
1540      srl(dst, src, shift - kSmiTagSize);
1541      And(dst, dst, Operand(mask));
1542    } else {
1543      And(dst, src, Operand(mask));
1544    }
1545  }
1546
1547  template<typename Field>
1548  void DecodeFieldToSmi(Register reg) {
1549    DecodeField<Field>(reg, reg);
1550  }
1551
1552  // Generates function and stub prologue code.
1553  void StubPrologue();
1554  void Prologue(bool code_pre_aging);
1555
1556  // Activation support.
1557  void EnterFrame(StackFrame::Type type);
1558  void LeaveFrame(StackFrame::Type type);
1559
1560  // Patch the relocated value (lui/ori pair).
1561  void PatchRelocatedValue(Register li_location,
1562                           Register scratch,
1563                           Register new_value);
1564  // Get the relocatad value (loaded data) from the lui/ori pair.
1565  void GetRelocatedValue(Register li_location,
1566                         Register value,
1567                         Register scratch);
1568
1569  // Expects object in a0 and returns map with validated enum cache
1570  // in a0.  Assumes that any other register can be used as a scratch.
1571  void CheckEnumCache(Register null_value, Label* call_runtime);
1572
1573  // AllocationMemento support. Arrays may have an associated
1574  // AllocationMemento object that can be checked for in order to pretransition
1575  // to another type.
1576  // On entry, receiver_reg should point to the array object.
1577  // scratch_reg gets clobbered.
1578  // If allocation info is present, jump to allocation_memento_present.
1579  void TestJSArrayForAllocationMemento(
1580      Register receiver_reg,
1581      Register scratch_reg,
1582      Label* no_memento_found,
1583      Condition cond = al,
1584      Label* allocation_memento_present = NULL);
1585
1586  void JumpIfJSArrayHasAllocationMemento(Register receiver_reg,
1587                                         Register scratch_reg,
1588                                         Label* memento_found) {
1589    Label no_memento_found;
1590    TestJSArrayForAllocationMemento(receiver_reg, scratch_reg,
1591                                    &no_memento_found, eq, memento_found);
1592    bind(&no_memento_found);
1593  }
1594
1595  // Jumps to found label if a prototype map has dictionary elements.
1596  void JumpIfDictionaryInPrototypeChain(Register object, Register scratch0,
1597                                        Register scratch1, Label* found);
1598
1599 private:
1600  void CallCFunctionHelper(Register function,
1601                           int num_reg_arguments,
1602                           int num_double_arguments);
1603
1604  void BranchAndLinkShort(int16_t offset, BranchDelaySlot bdslot = PROTECT);
1605  void BranchAndLinkShort(int16_t offset, Condition cond, Register rs,
1606                          const Operand& rt,
1607                          BranchDelaySlot bdslot = PROTECT);
1608  void BranchAndLinkShort(Label* L, BranchDelaySlot bdslot = PROTECT);
1609  void BranchAndLinkShort(Label* L, Condition cond, Register rs,
1610                          const Operand& rt,
1611                          BranchDelaySlot bdslot = PROTECT);
1612  void J(Label* L, BranchDelaySlot bdslot);
1613  void Jr(Label* L, BranchDelaySlot bdslot);
1614  void Jalr(Label* L, BranchDelaySlot bdslot);
1615
1616  // Helper functions for generating invokes.
1617  void InvokePrologue(const ParameterCount& expected,
1618                      const ParameterCount& actual,
1619                      Handle<Code> code_constant,
1620                      Register code_reg,
1621                      Label* done,
1622                      bool* definitely_mismatches,
1623                      InvokeFlag flag,
1624                      const CallWrapper& call_wrapper);
1625
1626  // Get the code for the given builtin. Returns if able to resolve
1627  // the function in the 'resolved' flag.
1628  Handle<Code> ResolveBuiltin(Builtins::JavaScript id, bool* resolved);
1629
1630  void InitializeNewString(Register string,
1631                           Register length,
1632                           Heap::RootListIndex map_index,
1633                           Register scratch1,
1634                           Register scratch2);
1635
1636  // Helper for implementing JumpIfNotInNewSpace and JumpIfInNewSpace.
1637  void InNewSpace(Register object,
1638                  Register scratch,
1639                  Condition cond,  // eq for new space, ne otherwise.
1640                  Label* branch);
1641
1642  // Helper for finding the mark bits for an address.  Afterwards, the
1643  // bitmap register points at the word with the mark bits and the mask
1644  // the position of the first bit.  Leaves addr_reg unchanged.
1645  inline void GetMarkBits(Register addr_reg,
1646                          Register bitmap_reg,
1647                          Register mask_reg);
1648
1649  // Helper for throwing exceptions.  Compute a handler address and jump to
1650  // it.  See the implementation for register usage.
1651  void JumpToHandlerEntry();
1652
1653  // Compute memory operands for safepoint stack slots.
1654  static int SafepointRegisterStackIndex(int reg_code);
1655  MemOperand SafepointRegisterSlot(Register reg);
1656  MemOperand SafepointRegistersAndDoublesSlot(Register reg);
1657
1658  bool generating_stub_;
1659  bool has_frame_;
1660  // This handle will be patched with the code object on installation.
1661  Handle<Object> code_object_;
1662
1663  // Needs access to SafepointRegisterStackIndex for compiled frame
1664  // traversal.
1665  friend class StandardFrame;
1666};
1667
1668
1669// The code patcher is used to patch (typically) small parts of code e.g. for
1670// debugging and other types of instrumentation. When using the code patcher
1671// the exact number of bytes specified must be emitted. It is not legal to emit
1672// relocation information. If any of these constraints are violated it causes
1673// an assertion to fail.
1674class CodePatcher {
1675 public:
1676  enum FlushICache {
1677    FLUSH,
1678    DONT_FLUSH
1679  };
1680
1681  CodePatcher(byte* address,
1682              int instructions,
1683              FlushICache flush_cache = FLUSH);
1684  virtual ~CodePatcher();
1685
1686  // Macro assembler to emit code.
1687  MacroAssembler* masm() { return &masm_; }
1688
1689  // Emit an instruction directly.
1690  void Emit(Instr instr);
1691
1692  // Emit an address directly.
1693  void Emit(Address addr);
1694
1695  // Change the condition part of an instruction leaving the rest of the current
1696  // instruction unchanged.
1697  void ChangeBranchCondition(Condition cond);
1698
1699 private:
1700  byte* address_;  // The address of the code being patched.
1701  int size_;  // Number of bytes of the expected patch size.
1702  MacroAssembler masm_;  // Macro assembler used to generate the code.
1703  FlushICache flush_cache_;  // Whether to flush the I cache after patching.
1704};
1705
1706
1707
1708#ifdef GENERATED_CODE_COVERAGE
1709#define CODE_COVERAGE_STRINGIFY(x) #x
1710#define CODE_COVERAGE_TOSTRING(x) CODE_COVERAGE_STRINGIFY(x)
1711#define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
1712#define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
1713#else
1714#define ACCESS_MASM(masm) masm->
1715#endif
1716
1717} }  // namespace v8::internal
1718
1719#endif  // V8_MIPS_MACRO_ASSEMBLER_MIPS_H_
1720