1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 /* This file contains codegen for the Thumb2 ISA. */
18 
19 #include "arm_lir.h"
20 #include "codegen_arm.h"
21 #include "dex/quick/mir_to_lir-inl.h"
22 #include "dex/reg_storage_eq.h"
23 #include "entrypoints/quick/quick_entrypoints.h"
24 #include "mirror/array.h"
25 
26 namespace art {
27 
OpCmpBranch(ConditionCode cond,RegStorage src1,RegStorage src2,LIR * target)28 LIR* ArmMir2Lir::OpCmpBranch(ConditionCode cond, RegStorage src1, RegStorage src2, LIR* target) {
29   OpRegReg(kOpCmp, src1, src2);
30   return OpCondBranch(cond, target);
31 }
32 
33 /*
34  * Generate a Thumb2 IT instruction, which can nullify up to
35  * four subsequent instructions based on a condition and its
36  * inverse.  The condition applies to the first instruction, which
37  * is executed if the condition is met.  The string "guide" consists
38  * of 0 to 3 chars, and applies to the 2nd through 4th instruction.
39  * A "T" means the instruction is executed if the condition is
40  * met, and an "E" means the instruction is executed if the condition
41  * is not met.
42  */
OpIT(ConditionCode ccode,const char * guide)43 LIR* ArmMir2Lir::OpIT(ConditionCode ccode, const char* guide) {
44   int mask;
45   int mask3 = 0;
46   int mask2 = 0;
47   int mask1 = 0;
48   ArmConditionCode code = ArmConditionEncoding(ccode);
49   int cond_bit = code & 1;
50   int alt_bit = cond_bit ^ 1;
51 
52   // Note: case fallthroughs intentional
53   switch (strlen(guide)) {
54     case 3:
55       mask1 = (guide[2] == 'T') ? cond_bit : alt_bit;
56     case 2:
57       mask2 = (guide[1] == 'T') ? cond_bit : alt_bit;
58     case 1:
59       mask3 = (guide[0] == 'T') ? cond_bit : alt_bit;
60       break;
61     case 0:
62       break;
63     default:
64       LOG(FATAL) << "OAT: bad case in OpIT";
65   }
66   mask = (mask3 << 3) | (mask2 << 2) | (mask1 << 1) |
67        (1 << (3 - strlen(guide)));
68   return NewLIR2(kThumb2It, code, mask);
69 }
70 
UpdateIT(LIR * it,const char * new_guide)71 void ArmMir2Lir::UpdateIT(LIR* it, const char* new_guide) {
72   int mask;
73   int mask3 = 0;
74   int mask2 = 0;
75   int mask1 = 0;
76   ArmConditionCode code = static_cast<ArmConditionCode>(it->operands[0]);
77   int cond_bit = code & 1;
78   int alt_bit = cond_bit ^ 1;
79 
80   // Note: case fallthroughs intentional
81   switch (strlen(new_guide)) {
82     case 3:
83       mask1 = (new_guide[2] == 'T') ? cond_bit : alt_bit;
84     case 2:
85       mask2 = (new_guide[1] == 'T') ? cond_bit : alt_bit;
86     case 1:
87       mask3 = (new_guide[0] == 'T') ? cond_bit : alt_bit;
88       break;
89     case 0:
90       break;
91     default:
92       LOG(FATAL) << "OAT: bad case in UpdateIT";
93   }
94   mask = (mask3 << 3) | (mask2 << 2) | (mask1 << 1) |
95       (1 << (3 - strlen(new_guide)));
96   it->operands[1] = mask;
97 }
98 
OpEndIT(LIR * it)99 void ArmMir2Lir::OpEndIT(LIR* it) {
100   // TODO: use the 'it' pointer to do some checks with the LIR, for example
101   //       we could check that the number of instructions matches the mask
102   //       in the IT instruction.
103   CHECK(it != nullptr);
104   GenBarrier();
105 }
106 
107 /*
108  * 64-bit 3way compare function.
109  *     mov   rX, #-1
110  *     cmp   op1hi, op2hi
111  *     blt   done
112  *     bgt   flip
113  *     sub   rX, op1lo, op2lo (treat as unsigned)
114  *     beq   done
115  *     ite   hi
116  *     mov(hi)   rX, #-1
117  *     mov(!hi)  rX, #1
118  * flip:
119  *     neg   rX
120  * done:
121  */
GenCmpLong(RegLocation rl_dest,RegLocation rl_src1,RegLocation rl_src2)122 void ArmMir2Lir::GenCmpLong(RegLocation rl_dest, RegLocation rl_src1, RegLocation rl_src2) {
123   LIR* target1;
124   LIR* target2;
125   rl_src1 = LoadValueWide(rl_src1, kCoreReg);
126   rl_src2 = LoadValueWide(rl_src2, kCoreReg);
127   RegStorage t_reg = AllocTemp();
128   LoadConstant(t_reg, -1);
129   OpRegReg(kOpCmp, rl_src1.reg.GetHigh(), rl_src2.reg.GetHigh());
130   LIR* branch1 = OpCondBranch(kCondLt, NULL);
131   LIR* branch2 = OpCondBranch(kCondGt, NULL);
132   OpRegRegReg(kOpSub, t_reg, rl_src1.reg.GetLow(), rl_src2.reg.GetLow());
133   LIR* branch3 = OpCondBranch(kCondEq, NULL);
134 
135   LIR* it = OpIT(kCondHi, "E");
136   NewLIR2(kThumb2MovI8M, t_reg.GetReg(), ModifiedImmediate(-1));
137   LoadConstant(t_reg, 1);
138   OpEndIT(it);
139 
140   target2 = NewLIR0(kPseudoTargetLabel);
141   OpRegReg(kOpNeg, t_reg, t_reg);
142 
143   target1 = NewLIR0(kPseudoTargetLabel);
144 
145   RegLocation rl_temp = LocCReturn();  // Just using as template, will change
146   rl_temp.reg.SetReg(t_reg.GetReg());
147   StoreValue(rl_dest, rl_temp);
148   FreeTemp(t_reg);
149 
150   branch1->target = target1;
151   branch2->target = target2;
152   branch3->target = branch1->target;
153 }
154 
GenFusedLongCmpImmBranch(BasicBlock * bb,RegLocation rl_src1,int64_t val,ConditionCode ccode)155 void ArmMir2Lir::GenFusedLongCmpImmBranch(BasicBlock* bb, RegLocation rl_src1,
156                                           int64_t val, ConditionCode ccode) {
157   int32_t val_lo = Low32Bits(val);
158   int32_t val_hi = High32Bits(val);
159   DCHECK_GE(ModifiedImmediate(val_lo), 0);
160   DCHECK_GE(ModifiedImmediate(val_hi), 0);
161   LIR* taken = &block_label_list_[bb->taken];
162   LIR* not_taken = &block_label_list_[bb->fall_through];
163   rl_src1 = LoadValueWide(rl_src1, kCoreReg);
164   RegStorage low_reg = rl_src1.reg.GetLow();
165   RegStorage high_reg = rl_src1.reg.GetHigh();
166 
167   if (val == 0 && (ccode == kCondEq || ccode == kCondNe)) {
168     RegStorage t_reg = AllocTemp();
169     NewLIR4(kThumb2OrrRRRs, t_reg.GetReg(), low_reg.GetReg(), high_reg.GetReg(), 0);
170     FreeTemp(t_reg);
171     OpCondBranch(ccode, taken);
172     return;
173   }
174 
175   switch (ccode) {
176     case kCondEq:
177     case kCondNe:
178       OpCmpImmBranch(kCondNe, high_reg, val_hi, (ccode == kCondEq) ? not_taken : taken);
179       break;
180     case kCondLt:
181       OpCmpImmBranch(kCondLt, high_reg, val_hi, taken);
182       OpCmpImmBranch(kCondGt, high_reg, val_hi, not_taken);
183       ccode = kCondUlt;
184       break;
185     case kCondLe:
186       OpCmpImmBranch(kCondLt, high_reg, val_hi, taken);
187       OpCmpImmBranch(kCondGt, high_reg, val_hi, not_taken);
188       ccode = kCondLs;
189       break;
190     case kCondGt:
191       OpCmpImmBranch(kCondGt, high_reg, val_hi, taken);
192       OpCmpImmBranch(kCondLt, high_reg, val_hi, not_taken);
193       ccode = kCondHi;
194       break;
195     case kCondGe:
196       OpCmpImmBranch(kCondGt, high_reg, val_hi, taken);
197       OpCmpImmBranch(kCondLt, high_reg, val_hi, not_taken);
198       ccode = kCondUge;
199       break;
200     default:
201       LOG(FATAL) << "Unexpected ccode: " << ccode;
202   }
203   OpCmpImmBranch(ccode, low_reg, val_lo, taken);
204 }
205 
GenSelectConst32(RegStorage left_op,RegStorage right_op,ConditionCode code,int32_t true_val,int32_t false_val,RegStorage rs_dest,int dest_reg_class)206 void ArmMir2Lir::GenSelectConst32(RegStorage left_op, RegStorage right_op, ConditionCode code,
207                                   int32_t true_val, int32_t false_val, RegStorage rs_dest,
208                                   int dest_reg_class) {
209   // TODO: Generalize the IT below to accept more than one-instruction loads.
210   DCHECK(InexpensiveConstantInt(true_val));
211   DCHECK(InexpensiveConstantInt(false_val));
212 
213   if ((true_val == 0 && code == kCondEq) ||
214       (false_val == 0 && code == kCondNe)) {
215     OpRegRegReg(kOpSub, rs_dest, left_op, right_op);
216     DCHECK(last_lir_insn_->u.m.def_mask->HasBit(ResourceMask::kCCode));
217     LIR* it = OpIT(kCondNe, "");
218     LoadConstant(rs_dest, code == kCondEq ? false_val : true_val);
219     OpEndIT(it);
220     return;
221   }
222 
223   OpRegReg(kOpCmp, left_op, right_op);  // Same?
224   LIR* it = OpIT(code, "E");   // if-convert the test
225   LoadConstant(rs_dest, true_val);      // .eq case - load true
226   LoadConstant(rs_dest, false_val);     // .eq case - load true
227   OpEndIT(it);
228 }
229 
GenSelect(BasicBlock * bb,MIR * mir)230 void ArmMir2Lir::GenSelect(BasicBlock* bb, MIR* mir) {
231   RegLocation rl_result;
232   RegLocation rl_src = mir_graph_->GetSrc(mir, 0);
233   RegLocation rl_dest = mir_graph_->GetDest(mir);
234   // Avoid using float regs here.
235   RegisterClass src_reg_class = rl_src.ref ? kRefReg : kCoreReg;
236   RegisterClass result_reg_class = rl_dest.ref ? kRefReg : kCoreReg;
237   rl_src = LoadValue(rl_src, src_reg_class);
238   ConditionCode ccode = mir->meta.ccode;
239   if (mir->ssa_rep->num_uses == 1) {
240     // CONST case
241     int true_val = mir->dalvikInsn.vB;
242     int false_val = mir->dalvikInsn.vC;
243     rl_result = EvalLoc(rl_dest, result_reg_class, true);
244     // Change kCondNe to kCondEq for the special cases below.
245     if (ccode == kCondNe) {
246       ccode = kCondEq;
247       std::swap(true_val, false_val);
248     }
249     bool cheap_false_val = InexpensiveConstantInt(false_val);
250     if (cheap_false_val && ccode == kCondEq && (true_val == 0 || true_val == -1)) {
251       OpRegRegImm(kOpSub, rl_result.reg, rl_src.reg, -true_val);
252       DCHECK(last_lir_insn_->u.m.def_mask->HasBit(ResourceMask::kCCode));
253       LIR* it = OpIT(true_val == 0 ? kCondNe : kCondUge, "");
254       LoadConstant(rl_result.reg, false_val);
255       OpEndIT(it);  // Add a scheduling barrier to keep the IT shadow intact
256     } else if (cheap_false_val && ccode == kCondEq && true_val == 1) {
257       OpRegRegImm(kOpRsub, rl_result.reg, rl_src.reg, 1);
258       DCHECK(last_lir_insn_->u.m.def_mask->HasBit(ResourceMask::kCCode));
259       LIR* it = OpIT(kCondLs, "");
260       LoadConstant(rl_result.reg, false_val);
261       OpEndIT(it);  // Add a scheduling barrier to keep the IT shadow intact
262     } else if (cheap_false_val && InexpensiveConstantInt(true_val)) {
263       OpRegImm(kOpCmp, rl_src.reg, 0);
264       LIR* it = OpIT(ccode, "E");
265       LoadConstant(rl_result.reg, true_val);
266       LoadConstant(rl_result.reg, false_val);
267       OpEndIT(it);  // Add a scheduling barrier to keep the IT shadow intact
268     } else {
269       // Unlikely case - could be tuned.
270       RegStorage t_reg1 = AllocTypedTemp(false, result_reg_class);
271       RegStorage t_reg2 = AllocTypedTemp(false, result_reg_class);
272       LoadConstant(t_reg1, true_val);
273       LoadConstant(t_reg2, false_val);
274       OpRegImm(kOpCmp, rl_src.reg, 0);
275       LIR* it = OpIT(ccode, "E");
276       OpRegCopy(rl_result.reg, t_reg1);
277       OpRegCopy(rl_result.reg, t_reg2);
278       OpEndIT(it);  // Add a scheduling barrier to keep the IT shadow intact
279     }
280   } else {
281     // MOVE case
282     RegLocation rl_true = mir_graph_->reg_location_[mir->ssa_rep->uses[1]];
283     RegLocation rl_false = mir_graph_->reg_location_[mir->ssa_rep->uses[2]];
284     rl_true = LoadValue(rl_true, result_reg_class);
285     rl_false = LoadValue(rl_false, result_reg_class);
286     rl_result = EvalLoc(rl_dest, result_reg_class, true);
287     OpRegImm(kOpCmp, rl_src.reg, 0);
288     LIR* it = nullptr;
289     if (rl_result.reg.GetReg() == rl_true.reg.GetReg()) {  // Is the "true" case already in place?
290       it = OpIT(NegateComparison(ccode), "");
291       OpRegCopy(rl_result.reg, rl_false.reg);
292     } else if (rl_result.reg.GetReg() == rl_false.reg.GetReg()) {  // False case in place?
293       it = OpIT(ccode, "");
294       OpRegCopy(rl_result.reg, rl_true.reg);
295     } else {  // Normal - select between the two.
296       it = OpIT(ccode, "E");
297       OpRegCopy(rl_result.reg, rl_true.reg);
298       OpRegCopy(rl_result.reg, rl_false.reg);
299     }
300     OpEndIT(it);  // Add a scheduling barrier to keep the IT shadow intact
301   }
302   StoreValue(rl_dest, rl_result);
303 }
304 
GenFusedLongCmpBranch(BasicBlock * bb,MIR * mir)305 void ArmMir2Lir::GenFusedLongCmpBranch(BasicBlock* bb, MIR* mir) {
306   RegLocation rl_src1 = mir_graph_->GetSrcWide(mir, 0);
307   RegLocation rl_src2 = mir_graph_->GetSrcWide(mir, 2);
308   // Normalize such that if either operand is constant, src2 will be constant.
309   ConditionCode ccode = mir->meta.ccode;
310   if (rl_src1.is_const) {
311     std::swap(rl_src1, rl_src2);
312     ccode = FlipComparisonOrder(ccode);
313   }
314   if (rl_src2.is_const) {
315     rl_src2 = UpdateLocWide(rl_src2);
316     // Do special compare/branch against simple const operand if not already in registers.
317     int64_t val = mir_graph_->ConstantValueWide(rl_src2);
318     if ((rl_src2.location != kLocPhysReg) &&
319         ((ModifiedImmediate(Low32Bits(val)) >= 0) && (ModifiedImmediate(High32Bits(val)) >= 0))) {
320       GenFusedLongCmpImmBranch(bb, rl_src1, val, ccode);
321       return;
322     }
323   }
324   LIR* taken = &block_label_list_[bb->taken];
325   LIR* not_taken = &block_label_list_[bb->fall_through];
326   rl_src1 = LoadValueWide(rl_src1, kCoreReg);
327   rl_src2 = LoadValueWide(rl_src2, kCoreReg);
328   OpRegReg(kOpCmp, rl_src1.reg.GetHigh(), rl_src2.reg.GetHigh());
329   switch (ccode) {
330     case kCondEq:
331       OpCondBranch(kCondNe, not_taken);
332       break;
333     case kCondNe:
334       OpCondBranch(kCondNe, taken);
335       break;
336     case kCondLt:
337       OpCondBranch(kCondLt, taken);
338       OpCondBranch(kCondGt, not_taken);
339       ccode = kCondUlt;
340       break;
341     case kCondLe:
342       OpCondBranch(kCondLt, taken);
343       OpCondBranch(kCondGt, not_taken);
344       ccode = kCondLs;
345       break;
346     case kCondGt:
347       OpCondBranch(kCondGt, taken);
348       OpCondBranch(kCondLt, not_taken);
349       ccode = kCondHi;
350       break;
351     case kCondGe:
352       OpCondBranch(kCondGt, taken);
353       OpCondBranch(kCondLt, not_taken);
354       ccode = kCondUge;
355       break;
356     default:
357       LOG(FATAL) << "Unexpected ccode: " << ccode;
358   }
359   OpRegReg(kOpCmp, rl_src1.reg.GetLow(), rl_src2.reg.GetLow());
360   OpCondBranch(ccode, taken);
361 }
362 
363 /*
364  * Generate a register comparison to an immediate and branch.  Caller
365  * is responsible for setting branch target field.
366  */
OpCmpImmBranch(ConditionCode cond,RegStorage reg,int check_value,LIR * target)367 LIR* ArmMir2Lir::OpCmpImmBranch(ConditionCode cond, RegStorage reg, int check_value, LIR* target) {
368   LIR* branch = nullptr;
369   ArmConditionCode arm_cond = ArmConditionEncoding(cond);
370   /*
371    * A common use of OpCmpImmBranch is for null checks, and using the Thumb 16-bit
372    * compare-and-branch if zero is ideal if it will reach.  However, because null checks
373    * branch forward to a slow path, they will frequently not reach - and thus have to
374    * be converted to a long form during assembly (which will trigger another assembly
375    * pass).  Here we estimate the branch distance for checks, and if large directly
376    * generate the long form in an attempt to avoid an extra assembly pass.
377    * TODO: consider interspersing slowpaths in code following unconditional branches.
378    */
379   bool skip = ((target != NULL) && (target->opcode == kPseudoThrowTarget));
380   skip &= ((cu_->code_item->insns_size_in_code_units_ - current_dalvik_offset_) > 64);
381   if (!skip && reg.Low8() && (check_value == 0)) {
382     if (arm_cond == kArmCondEq || arm_cond == kArmCondNe) {
383       branch = NewLIR2((arm_cond == kArmCondEq) ? kThumb2Cbz : kThumb2Cbnz,
384                        reg.GetReg(), 0);
385     } else if (arm_cond == kArmCondLs) {
386       // kArmCondLs is an unsigned less or equal. A comparison r <= 0 is then the same as cbz.
387       // This case happens for a bounds check of array[0].
388       branch = NewLIR2(kThumb2Cbz, reg.GetReg(), 0);
389     }
390   }
391 
392   if (branch == nullptr) {
393     OpRegImm(kOpCmp, reg, check_value);
394     branch = NewLIR2(kThumbBCond, 0, arm_cond);
395   }
396 
397   branch->target = target;
398   return branch;
399 }
400 
OpRegCopyNoInsert(RegStorage r_dest,RegStorage r_src)401 LIR* ArmMir2Lir::OpRegCopyNoInsert(RegStorage r_dest, RegStorage r_src) {
402   LIR* res;
403   int opcode;
404   // If src or dest is a pair, we'll be using low reg.
405   if (r_dest.IsPair()) {
406     r_dest = r_dest.GetLow();
407   }
408   if (r_src.IsPair()) {
409     r_src = r_src.GetLow();
410   }
411   if (r_dest.IsFloat() || r_src.IsFloat())
412     return OpFpRegCopy(r_dest, r_src);
413   if (r_dest.Low8() && r_src.Low8())
414     opcode = kThumbMovRR;
415   else if (!r_dest.Low8() && !r_src.Low8())
416      opcode = kThumbMovRR_H2H;
417   else if (r_dest.Low8())
418      opcode = kThumbMovRR_H2L;
419   else
420      opcode = kThumbMovRR_L2H;
421   res = RawLIR(current_dalvik_offset_, opcode, r_dest.GetReg(), r_src.GetReg());
422   if (!(cu_->disable_opt & (1 << kSafeOptimizations)) && r_dest == r_src) {
423     res->flags.is_nop = true;
424   }
425   return res;
426 }
427 
OpRegCopy(RegStorage r_dest,RegStorage r_src)428 void ArmMir2Lir::OpRegCopy(RegStorage r_dest, RegStorage r_src) {
429   if (r_dest != r_src) {
430     LIR* res = OpRegCopyNoInsert(r_dest, r_src);
431     AppendLIR(res);
432   }
433 }
434 
OpRegCopyWide(RegStorage r_dest,RegStorage r_src)435 void ArmMir2Lir::OpRegCopyWide(RegStorage r_dest, RegStorage r_src) {
436   if (r_dest != r_src) {
437     bool dest_fp = r_dest.IsFloat();
438     bool src_fp = r_src.IsFloat();
439     DCHECK(r_dest.Is64Bit());
440     DCHECK(r_src.Is64Bit());
441     if (dest_fp) {
442       if (src_fp) {
443         OpRegCopy(r_dest, r_src);
444       } else {
445         NewLIR3(kThumb2Fmdrr, r_dest.GetReg(), r_src.GetLowReg(), r_src.GetHighReg());
446       }
447     } else {
448       if (src_fp) {
449         NewLIR3(kThumb2Fmrrd, r_dest.GetLowReg(), r_dest.GetHighReg(), r_src.GetReg());
450       } else {
451         // Handle overlap
452         if (r_src.GetHighReg() == r_dest.GetLowReg()) {
453           DCHECK_NE(r_src.GetLowReg(), r_dest.GetHighReg());
454           OpRegCopy(r_dest.GetHigh(), r_src.GetHigh());
455           OpRegCopy(r_dest.GetLow(), r_src.GetLow());
456         } else {
457           OpRegCopy(r_dest.GetLow(), r_src.GetLow());
458           OpRegCopy(r_dest.GetHigh(), r_src.GetHigh());
459         }
460       }
461     }
462   }
463 }
464 
465 // Table of magic divisors
466 struct MagicTable {
467   uint32_t magic;
468   uint32_t shift;
469   DividePattern pattern;
470 };
471 
472 static const MagicTable magic_table[] = {
473   {0, 0, DivideNone},        // 0
474   {0, 0, DivideNone},        // 1
475   {0, 0, DivideNone},        // 2
476   {0x55555556, 0, Divide3},  // 3
477   {0, 0, DivideNone},        // 4
478   {0x66666667, 1, Divide5},  // 5
479   {0x2AAAAAAB, 0, Divide3},  // 6
480   {0x92492493, 2, Divide7},  // 7
481   {0, 0, DivideNone},        // 8
482   {0x38E38E39, 1, Divide5},  // 9
483   {0x66666667, 2, Divide5},  // 10
484   {0x2E8BA2E9, 1, Divide5},  // 11
485   {0x2AAAAAAB, 1, Divide5},  // 12
486   {0x4EC4EC4F, 2, Divide5},  // 13
487   {0x92492493, 3, Divide7},  // 14
488   {0x88888889, 3, Divide7},  // 15
489 };
490 
491 // Integer division by constant via reciprocal multiply (Hacker's Delight, 10-4)
SmallLiteralDivRem(Instruction::Code dalvik_opcode,bool is_div,RegLocation rl_src,RegLocation rl_dest,int lit)492 bool ArmMir2Lir::SmallLiteralDivRem(Instruction::Code dalvik_opcode, bool is_div,
493                                     RegLocation rl_src, RegLocation rl_dest, int lit) {
494   if ((lit < 0) || (lit >= static_cast<int>(sizeof(magic_table)/sizeof(magic_table[0])))) {
495     return false;
496   }
497   DividePattern pattern = magic_table[lit].pattern;
498   if (pattern == DivideNone) {
499     return false;
500   }
501 
502   RegStorage r_magic = AllocTemp();
503   LoadConstant(r_magic, magic_table[lit].magic);
504   rl_src = LoadValue(rl_src, kCoreReg);
505   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
506   RegStorage r_hi = AllocTemp();
507   RegStorage r_lo = AllocTemp();
508 
509   // rl_dest and rl_src might overlap.
510   // Reuse r_hi to save the div result for reminder case.
511   RegStorage r_div_result = is_div ? rl_result.reg : r_hi;
512 
513   NewLIR4(kThumb2Smull, r_lo.GetReg(), r_hi.GetReg(), r_magic.GetReg(), rl_src.reg.GetReg());
514   switch (pattern) {
515     case Divide3:
516       OpRegRegRegShift(kOpSub, r_div_result, r_hi, rl_src.reg, EncodeShift(kArmAsr, 31));
517       break;
518     case Divide5:
519       OpRegRegImm(kOpAsr, r_lo, rl_src.reg, 31);
520       OpRegRegRegShift(kOpRsub, r_div_result, r_lo, r_hi,
521                        EncodeShift(kArmAsr, magic_table[lit].shift));
522       break;
523     case Divide7:
524       OpRegReg(kOpAdd, r_hi, rl_src.reg);
525       OpRegRegImm(kOpAsr, r_lo, rl_src.reg, 31);
526       OpRegRegRegShift(kOpRsub, r_div_result, r_lo, r_hi,
527                        EncodeShift(kArmAsr, magic_table[lit].shift));
528       break;
529     default:
530       LOG(FATAL) << "Unexpected pattern: " << pattern;
531   }
532 
533   if (!is_div) {
534     // div_result = src / lit
535     // tmp1 = div_result * lit
536     // dest = src - tmp1
537     RegStorage tmp1 = r_lo;
538     EasyMultiplyOp ops[2];
539 
540     bool canEasyMultiply = GetEasyMultiplyTwoOps(lit, ops);
541     DCHECK_NE(canEasyMultiply, false);
542 
543     GenEasyMultiplyTwoOps(tmp1, r_div_result, ops);
544     OpRegRegReg(kOpSub, rl_result.reg, rl_src.reg, tmp1);
545   }
546 
547   StoreValue(rl_dest, rl_result);
548   return true;
549 }
550 
551 // Try to convert *lit to 1 RegRegRegShift/RegRegShift form.
GetEasyMultiplyOp(int lit,ArmMir2Lir::EasyMultiplyOp * op)552 bool ArmMir2Lir::GetEasyMultiplyOp(int lit, ArmMir2Lir::EasyMultiplyOp* op) {
553   if (lit == 0) {
554     // Special case for *divide-by-zero*. The ops won't actually be used to generate code, as
555     // GenArithOpIntLit will directly generate exception-throwing code, and multiply-by-zero will
556     // have been optimized away earlier.
557     op->op = kOpInvalid;
558     return true;
559   }
560 
561   if (IsPowerOfTwo(lit)) {
562     op->op = kOpLsl;
563     op->shift = LowestSetBit(lit);
564     return true;
565   }
566 
567   if (IsPowerOfTwo(lit - 1)) {
568     op->op = kOpAdd;
569     op->shift = LowestSetBit(lit - 1);
570     return true;
571   }
572 
573   if (IsPowerOfTwo(lit + 1)) {
574     op->op = kOpRsub;
575     op->shift = LowestSetBit(lit + 1);
576     return true;
577   }
578 
579   op->op = kOpInvalid;
580   op->shift = 0;
581   return false;
582 }
583 
584 // Try to convert *lit to 1~2 RegRegRegShift/RegRegShift forms.
GetEasyMultiplyTwoOps(int lit,EasyMultiplyOp * ops)585 bool ArmMir2Lir::GetEasyMultiplyTwoOps(int lit, EasyMultiplyOp* ops) {
586   GetEasyMultiplyOp(lit, &ops[0]);
587   if (GetEasyMultiplyOp(lit, &ops[0])) {
588     ops[1].op = kOpInvalid;
589     ops[1].shift = 0;
590     return true;
591   }
592 
593   int lit1 = lit;
594   uint32_t shift = LowestSetBit(lit1);
595   if (GetEasyMultiplyOp(lit1 >> shift, &ops[0])) {
596     ops[1].op = kOpLsl;
597     ops[1].shift = shift;
598     return true;
599   }
600 
601   lit1 = lit - 1;
602   shift = LowestSetBit(lit1);
603   if (GetEasyMultiplyOp(lit1 >> shift, &ops[0])) {
604     ops[1].op = kOpAdd;
605     ops[1].shift = shift;
606     return true;
607   }
608 
609   lit1 = lit + 1;
610   shift = LowestSetBit(lit1);
611   if (GetEasyMultiplyOp(lit1 >> shift, &ops[0])) {
612     ops[1].op = kOpRsub;
613     ops[1].shift = shift;
614     return true;
615   }
616 
617   return false;
618 }
619 
620 // Generate instructions to do multiply.
621 // Additional temporary register is required,
622 // if it need to generate 2 instructions and src/dest overlap.
GenEasyMultiplyTwoOps(RegStorage r_dest,RegStorage r_src,EasyMultiplyOp * ops)623 void ArmMir2Lir::GenEasyMultiplyTwoOps(RegStorage r_dest, RegStorage r_src, EasyMultiplyOp* ops) {
624   // tmp1 = ( src << shift1) + [ src | -src | 0 ]
625   // dest = (tmp1 << shift2) + [ src | -src | 0 ]
626 
627   RegStorage r_tmp1;
628   if (ops[1].op == kOpInvalid) {
629     r_tmp1 = r_dest;
630   } else if (r_dest.GetReg() != r_src.GetReg()) {
631     r_tmp1 = r_dest;
632   } else {
633     r_tmp1 = AllocTemp();
634   }
635 
636   switch (ops[0].op) {
637     case kOpLsl:
638       OpRegRegImm(kOpLsl, r_tmp1, r_src, ops[0].shift);
639       break;
640     case kOpAdd:
641       OpRegRegRegShift(kOpAdd, r_tmp1, r_src, r_src, EncodeShift(kArmLsl, ops[0].shift));
642       break;
643     case kOpRsub:
644       OpRegRegRegShift(kOpRsub, r_tmp1, r_src, r_src, EncodeShift(kArmLsl, ops[0].shift));
645       break;
646     default:
647       DCHECK_EQ(ops[0].op, kOpInvalid);
648       break;
649   }
650 
651   switch (ops[1].op) {
652     case kOpInvalid:
653       return;
654     case kOpLsl:
655       OpRegRegImm(kOpLsl, r_dest, r_tmp1, ops[1].shift);
656       break;
657     case kOpAdd:
658       OpRegRegRegShift(kOpAdd, r_dest, r_src, r_tmp1, EncodeShift(kArmLsl, ops[1].shift));
659       break;
660     case kOpRsub:
661       OpRegRegRegShift(kOpRsub, r_dest, r_src, r_tmp1, EncodeShift(kArmLsl, ops[1].shift));
662       break;
663     default:
664       LOG(FATAL) << "Unexpected opcode passed to GenEasyMultiplyTwoOps";
665       break;
666   }
667 }
668 
EasyMultiply(RegLocation rl_src,RegLocation rl_dest,int lit)669 bool ArmMir2Lir::EasyMultiply(RegLocation rl_src, RegLocation rl_dest, int lit) {
670   EasyMultiplyOp ops[2];
671 
672   if (!GetEasyMultiplyTwoOps(lit, ops)) {
673     return false;
674   }
675 
676   rl_src = LoadValue(rl_src, kCoreReg);
677   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
678 
679   GenEasyMultiplyTwoOps(rl_result.reg, rl_src.reg, ops);
680   StoreValue(rl_dest, rl_result);
681   return true;
682 }
683 
GenDivRem(RegLocation rl_dest,RegLocation rl_src1,RegLocation rl_src2,bool is_div,bool check_zero)684 RegLocation ArmMir2Lir::GenDivRem(RegLocation rl_dest, RegLocation rl_src1,
685                       RegLocation rl_src2, bool is_div, bool check_zero) {
686   LOG(FATAL) << "Unexpected use of GenDivRem for Arm";
687   return rl_dest;
688 }
689 
GenDivRemLit(RegLocation rl_dest,RegLocation rl_src1,int lit,bool is_div)690 RegLocation ArmMir2Lir::GenDivRemLit(RegLocation rl_dest, RegLocation rl_src1, int lit, bool is_div) {
691   LOG(FATAL) << "Unexpected use of GenDivRemLit for Arm";
692   return rl_dest;
693 }
694 
GenDivRemLit(RegLocation rl_dest,RegStorage reg1,int lit,bool is_div)695 RegLocation ArmMir2Lir::GenDivRemLit(RegLocation rl_dest, RegStorage reg1, int lit, bool is_div) {
696   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
697 
698   // Put the literal in a temp.
699   RegStorage lit_temp = AllocTemp();
700   LoadConstant(lit_temp, lit);
701   // Use the generic case for div/rem with arg2 in a register.
702   // TODO: The literal temp can be freed earlier during a modulus to reduce reg pressure.
703   rl_result = GenDivRem(rl_result, reg1, lit_temp, is_div);
704   FreeTemp(lit_temp);
705 
706   return rl_result;
707 }
708 
GenDivRem(RegLocation rl_dest,RegStorage reg1,RegStorage reg2,bool is_div)709 RegLocation ArmMir2Lir::GenDivRem(RegLocation rl_dest, RegStorage reg1, RegStorage reg2,
710                                   bool is_div) {
711   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
712   if (is_div) {
713     // Simple case, use sdiv instruction.
714     OpRegRegReg(kOpDiv, rl_result.reg, reg1, reg2);
715   } else {
716     // Remainder case, use the following code:
717     // temp = reg1 / reg2      - integer division
718     // temp = temp * reg2
719     // dest = reg1 - temp
720 
721     RegStorage temp = AllocTemp();
722     OpRegRegReg(kOpDiv, temp, reg1, reg2);
723     OpRegReg(kOpMul, temp, reg2);
724     OpRegRegReg(kOpSub, rl_result.reg, reg1, temp);
725     FreeTemp(temp);
726   }
727 
728   return rl_result;
729 }
730 
GenInlinedMinMax(CallInfo * info,bool is_min,bool is_long)731 bool ArmMir2Lir::GenInlinedMinMax(CallInfo* info, bool is_min, bool is_long) {
732   DCHECK_EQ(cu_->instruction_set, kThumb2);
733   if (is_long) {
734     return false;
735   }
736   RegLocation rl_src1 = info->args[0];
737   RegLocation rl_src2 = info->args[1];
738   rl_src1 = LoadValue(rl_src1, kCoreReg);
739   rl_src2 = LoadValue(rl_src2, kCoreReg);
740   RegLocation rl_dest = InlineTarget(info);
741   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
742   OpRegReg(kOpCmp, rl_src1.reg, rl_src2.reg);
743   LIR* it = OpIT((is_min) ? kCondGt : kCondLt, "E");
744   OpRegReg(kOpMov, rl_result.reg, rl_src2.reg);
745   OpRegReg(kOpMov, rl_result.reg, rl_src1.reg);
746   OpEndIT(it);
747   StoreValue(rl_dest, rl_result);
748   return true;
749 }
750 
GenInlinedPeek(CallInfo * info,OpSize size)751 bool ArmMir2Lir::GenInlinedPeek(CallInfo* info, OpSize size) {
752   RegLocation rl_src_address = info->args[0];  // long address
753   rl_src_address = NarrowRegLoc(rl_src_address);  // ignore high half in info->args[1]
754   RegLocation rl_dest = InlineTarget(info);
755   RegLocation rl_address = LoadValue(rl_src_address, kCoreReg);
756   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
757   if (size == k64) {
758     // Fake unaligned LDRD by two unaligned LDR instructions on ARMv7 with SCTLR.A set to 0.
759     if (rl_address.reg.GetReg() != rl_result.reg.GetLowReg()) {
760       Load32Disp(rl_address.reg, 0, rl_result.reg.GetLow());
761       Load32Disp(rl_address.reg, 4, rl_result.reg.GetHigh());
762     } else {
763       Load32Disp(rl_address.reg, 4, rl_result.reg.GetHigh());
764       Load32Disp(rl_address.reg, 0, rl_result.reg.GetLow());
765     }
766     StoreValueWide(rl_dest, rl_result);
767   } else {
768     DCHECK(size == kSignedByte || size == kSignedHalf || size == k32);
769     // Unaligned load with LDR and LDRSH is allowed on ARMv7 with SCTLR.A set to 0.
770     LoadBaseDisp(rl_address.reg, 0, rl_result.reg, size, kNotVolatile);
771     StoreValue(rl_dest, rl_result);
772   }
773   return true;
774 }
775 
GenInlinedPoke(CallInfo * info,OpSize size)776 bool ArmMir2Lir::GenInlinedPoke(CallInfo* info, OpSize size) {
777   RegLocation rl_src_address = info->args[0];  // long address
778   rl_src_address = NarrowRegLoc(rl_src_address);  // ignore high half in info->args[1]
779   RegLocation rl_src_value = info->args[2];  // [size] value
780   RegLocation rl_address = LoadValue(rl_src_address, kCoreReg);
781   if (size == k64) {
782     // Fake unaligned STRD by two unaligned STR instructions on ARMv7 with SCTLR.A set to 0.
783     RegLocation rl_value = LoadValueWide(rl_src_value, kCoreReg);
784     StoreBaseDisp(rl_address.reg, 0, rl_value.reg.GetLow(), k32, kNotVolatile);
785     StoreBaseDisp(rl_address.reg, 4, rl_value.reg.GetHigh(), k32, kNotVolatile);
786   } else {
787     DCHECK(size == kSignedByte || size == kSignedHalf || size == k32);
788     // Unaligned store with STR and STRSH is allowed on ARMv7 with SCTLR.A set to 0.
789     RegLocation rl_value = LoadValue(rl_src_value, kCoreReg);
790     StoreBaseDisp(rl_address.reg, 0, rl_value.reg, size, kNotVolatile);
791   }
792   return true;
793 }
794 
795 // Generate a CAS with memory_order_seq_cst semantics.
GenInlinedCas(CallInfo * info,bool is_long,bool is_object)796 bool ArmMir2Lir::GenInlinedCas(CallInfo* info, bool is_long, bool is_object) {
797   DCHECK_EQ(cu_->instruction_set, kThumb2);
798   // Unused - RegLocation rl_src_unsafe = info->args[0];
799   RegLocation rl_src_obj = info->args[1];  // Object - known non-null
800   RegLocation rl_src_offset = info->args[2];  // long low
801   rl_src_offset = NarrowRegLoc(rl_src_offset);  // ignore high half in info->args[3]
802   RegLocation rl_src_expected = info->args[4];  // int, long or Object
803   // If is_long, high half is in info->args[5]
804   RegLocation rl_src_new_value = info->args[is_long ? 6 : 5];  // int, long or Object
805   // If is_long, high half is in info->args[7]
806   RegLocation rl_dest = InlineTarget(info);  // boolean place for result
807 
808   // We have only 5 temporary registers available and actually only 4 if the InlineTarget
809   // above locked one of the temps. For a straightforward CAS64 we need 7 registers:
810   // r_ptr (1), new_value (2), expected(2) and ldrexd result (2). If neither expected nor
811   // new_value is in a non-temp core register we shall reload them in the ldrex/strex loop
812   // into the same temps, reducing the number of required temps down to 5. We shall work
813   // around the potentially locked temp by using LR for r_ptr, unconditionally.
814   // TODO: Pass information about the need for more temps to the stack frame generation
815   // code so that we can rely on being able to allocate enough temps.
816   DCHECK(!GetRegInfo(rs_rARM_LR)->IsTemp());
817   MarkTemp(rs_rARM_LR);
818   FreeTemp(rs_rARM_LR);
819   LockTemp(rs_rARM_LR);
820   bool load_early = true;
821   if (is_long) {
822     RegStorage expected_reg = rl_src_expected.reg.IsPair() ? rl_src_expected.reg.GetLow() :
823         rl_src_expected.reg;
824     RegStorage new_val_reg = rl_src_new_value.reg.IsPair() ? rl_src_new_value.reg.GetLow() :
825         rl_src_new_value.reg;
826     bool expected_is_core_reg = rl_src_expected.location == kLocPhysReg && !expected_reg.IsFloat();
827     bool new_value_is_core_reg = rl_src_new_value.location == kLocPhysReg && !new_val_reg.IsFloat();
828     bool expected_is_good_reg = expected_is_core_reg && !IsTemp(expected_reg);
829     bool new_value_is_good_reg = new_value_is_core_reg && !IsTemp(new_val_reg);
830 
831     if (!expected_is_good_reg && !new_value_is_good_reg) {
832       // None of expected/new_value is non-temp reg, need to load both late
833       load_early = false;
834       // Make sure they are not in the temp regs and the load will not be skipped.
835       if (expected_is_core_reg) {
836         FlushRegWide(rl_src_expected.reg);
837         ClobberSReg(rl_src_expected.s_reg_low);
838         ClobberSReg(GetSRegHi(rl_src_expected.s_reg_low));
839         rl_src_expected.location = kLocDalvikFrame;
840       }
841       if (new_value_is_core_reg) {
842         FlushRegWide(rl_src_new_value.reg);
843         ClobberSReg(rl_src_new_value.s_reg_low);
844         ClobberSReg(GetSRegHi(rl_src_new_value.s_reg_low));
845         rl_src_new_value.location = kLocDalvikFrame;
846       }
847     }
848   }
849 
850   // Prevent reordering with prior memory operations.
851   GenMemBarrier(kAnyStore);
852 
853   RegLocation rl_object = LoadValue(rl_src_obj, kRefReg);
854   RegLocation rl_new_value;
855   if (!is_long) {
856     rl_new_value = LoadValue(rl_src_new_value);
857   } else if (load_early) {
858     rl_new_value = LoadValueWide(rl_src_new_value, kCoreReg);
859   }
860 
861   if (is_object && !mir_graph_->IsConstantNullRef(rl_new_value)) {
862     // Mark card for object assuming new value is stored.
863     MarkGCCard(rl_new_value.reg, rl_object.reg);
864   }
865 
866   RegLocation rl_offset = LoadValue(rl_src_offset, kCoreReg);
867 
868   RegStorage r_ptr = rs_rARM_LR;
869   OpRegRegReg(kOpAdd, r_ptr, rl_object.reg, rl_offset.reg);
870 
871   // Free now unneeded rl_object and rl_offset to give more temps.
872   ClobberSReg(rl_object.s_reg_low);
873   FreeTemp(rl_object.reg);
874   ClobberSReg(rl_offset.s_reg_low);
875   FreeTemp(rl_offset.reg);
876 
877   RegLocation rl_expected;
878   if (!is_long) {
879     rl_expected = LoadValue(rl_src_expected);
880   } else if (load_early) {
881     rl_expected = LoadValueWide(rl_src_expected, kCoreReg);
882   } else {
883     // NOTE: partially defined rl_expected & rl_new_value - but we just want the regs.
884     RegStorage low_reg = AllocTemp();
885     RegStorage high_reg = AllocTemp();
886     rl_new_value.reg = RegStorage::MakeRegPair(low_reg, high_reg);
887     rl_expected = rl_new_value;
888   }
889 
890   // do {
891   //   tmp = [r_ptr] - expected;
892   // } while (tmp == 0 && failure([r_ptr] <- r_new_value));
893   // result = tmp != 0;
894 
895   RegStorage r_tmp = AllocTemp();
896   LIR* target = NewLIR0(kPseudoTargetLabel);
897 
898   LIR* it = nullptr;
899   if (is_long) {
900     RegStorage r_tmp_high = AllocTemp();
901     if (!load_early) {
902       LoadValueDirectWide(rl_src_expected, rl_expected.reg);
903     }
904     NewLIR3(kThumb2Ldrexd, r_tmp.GetReg(), r_tmp_high.GetReg(), r_ptr.GetReg());
905     OpRegReg(kOpSub, r_tmp, rl_expected.reg.GetLow());
906     OpRegReg(kOpSub, r_tmp_high, rl_expected.reg.GetHigh());
907     if (!load_early) {
908       LoadValueDirectWide(rl_src_new_value, rl_new_value.reg);
909     }
910     // Make sure we use ORR that sets the ccode
911     if (r_tmp.Low8() && r_tmp_high.Low8()) {
912       NewLIR2(kThumbOrr, r_tmp.GetReg(), r_tmp_high.GetReg());
913     } else {
914       NewLIR4(kThumb2OrrRRRs, r_tmp.GetReg(), r_tmp.GetReg(), r_tmp_high.GetReg(), 0);
915     }
916     FreeTemp(r_tmp_high);  // Now unneeded
917 
918     DCHECK(last_lir_insn_->u.m.def_mask->HasBit(ResourceMask::kCCode));
919     it = OpIT(kCondEq, "T");
920     NewLIR4(kThumb2Strexd /* eq */, r_tmp.GetReg(), rl_new_value.reg.GetLowReg(), rl_new_value.reg.GetHighReg(), r_ptr.GetReg());
921 
922   } else {
923     NewLIR3(kThumb2Ldrex, r_tmp.GetReg(), r_ptr.GetReg(), 0);
924     OpRegReg(kOpSub, r_tmp, rl_expected.reg);
925     DCHECK(last_lir_insn_->u.m.def_mask->HasBit(ResourceMask::kCCode));
926     it = OpIT(kCondEq, "T");
927     NewLIR4(kThumb2Strex /* eq */, r_tmp.GetReg(), rl_new_value.reg.GetReg(), r_ptr.GetReg(), 0);
928   }
929 
930   // Still one conditional left from OpIT(kCondEq, "T") from either branch
931   OpRegImm(kOpCmp /* eq */, r_tmp, 1);
932   OpEndIT(it);
933 
934   OpCondBranch(kCondEq, target);
935 
936   if (!load_early) {
937     FreeTemp(rl_expected.reg);  // Now unneeded.
938   }
939 
940   // Prevent reordering with subsequent memory operations.
941   GenMemBarrier(kLoadAny);
942 
943   // result := (tmp1 != 0) ? 0 : 1;
944   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
945   OpRegRegImm(kOpRsub, rl_result.reg, r_tmp, 1);
946   DCHECK(last_lir_insn_->u.m.def_mask->HasBit(ResourceMask::kCCode));
947   it = OpIT(kCondUlt, "");
948   LoadConstant(rl_result.reg, 0); /* cc */
949   FreeTemp(r_tmp);  // Now unneeded.
950   OpEndIT(it);     // Barrier to terminate OpIT.
951 
952   StoreValue(rl_dest, rl_result);
953 
954   // Now, restore lr to its non-temp status.
955   Clobber(rs_rARM_LR);
956   UnmarkTemp(rs_rARM_LR);
957   return true;
958 }
959 
GenInlinedArrayCopyCharArray(CallInfo * info)960 bool ArmMir2Lir::GenInlinedArrayCopyCharArray(CallInfo* info) {
961   constexpr int kLargeArrayThreshold = 256;
962 
963   RegLocation rl_src = info->args[0];
964   RegLocation rl_src_pos = info->args[1];
965   RegLocation rl_dst = info->args[2];
966   RegLocation rl_dst_pos = info->args[3];
967   RegLocation rl_length = info->args[4];
968   // Compile time check, handle exception by non-inline method to reduce related meta-data.
969   if ((rl_src_pos.is_const && (mir_graph_->ConstantValue(rl_src_pos) < 0)) ||
970       (rl_dst_pos.is_const && (mir_graph_->ConstantValue(rl_dst_pos) < 0)) ||
971       (rl_length.is_const && (mir_graph_->ConstantValue(rl_length) < 0))) {
972     return false;
973   }
974 
975   ClobberCallerSave();
976   LockCallTemps();  // Prepare for explicit register usage.
977   LockTemp(rs_r12);
978   RegStorage rs_src = rs_r0;
979   RegStorage rs_dst = rs_r1;
980   LoadValueDirectFixed(rl_src, rs_src);
981   LoadValueDirectFixed(rl_dst, rs_dst);
982 
983   // Handle null pointer exception in slow-path.
984   LIR* src_check_branch = OpCmpImmBranch(kCondEq, rs_src, 0, nullptr);
985   LIR* dst_check_branch = OpCmpImmBranch(kCondEq, rs_dst, 0, nullptr);
986   // Handle potential overlapping in slow-path.
987   LIR* src_dst_same = OpCmpBranch(kCondEq, rs_src, rs_dst, nullptr);
988   // Handle exception or big length in slow-path.
989   RegStorage rs_length = rs_r2;
990   LoadValueDirectFixed(rl_length, rs_length);
991   LIR* len_neg_or_too_big = OpCmpImmBranch(kCondHi, rs_length, kLargeArrayThreshold, nullptr);
992   // Src bounds check.
993   RegStorage rs_pos = rs_r3;
994   RegStorage rs_arr_length = rs_r12;
995   LoadValueDirectFixed(rl_src_pos, rs_pos);
996   LIR* src_pos_negative = OpCmpImmBranch(kCondLt, rs_pos, 0, nullptr);
997   Load32Disp(rs_src, mirror::Array::LengthOffset().Int32Value(), rs_arr_length);
998   OpRegReg(kOpSub, rs_arr_length, rs_pos);
999   LIR* src_bad_len = OpCmpBranch(kCondLt, rs_arr_length, rs_length, nullptr);
1000   // Dst bounds check.
1001   LoadValueDirectFixed(rl_dst_pos, rs_pos);
1002   LIR* dst_pos_negative = OpCmpImmBranch(kCondLt, rs_pos, 0, nullptr);
1003   Load32Disp(rs_dst, mirror::Array::LengthOffset().Int32Value(), rs_arr_length);
1004   OpRegReg(kOpSub, rs_arr_length, rs_pos);
1005   LIR* dst_bad_len = OpCmpBranch(kCondLt, rs_arr_length, rs_length, nullptr);
1006 
1007   // Everything is checked now.
1008   OpRegImm(kOpAdd, rs_dst, mirror::Array::DataOffset(2).Int32Value());
1009   OpRegReg(kOpAdd, rs_dst, rs_pos);
1010   OpRegReg(kOpAdd, rs_dst, rs_pos);
1011   OpRegImm(kOpAdd, rs_src, mirror::Array::DataOffset(2).Int32Value());
1012   LoadValueDirectFixed(rl_src_pos, rs_pos);
1013   OpRegReg(kOpAdd, rs_src, rs_pos);
1014   OpRegReg(kOpAdd, rs_src, rs_pos);
1015 
1016   RegStorage rs_tmp = rs_pos;
1017   OpRegRegImm(kOpLsl, rs_length, rs_length, 1);
1018 
1019   // Copy one element.
1020   OpRegRegImm(kOpAnd, rs_tmp, rs_length, 2);
1021   LIR* jmp_to_begin_loop = OpCmpImmBranch(kCondEq, rs_tmp, 0, nullptr);
1022   OpRegImm(kOpSub, rs_length, 2);
1023   LoadBaseIndexed(rs_src, rs_length, rs_tmp, 0, kSignedHalf);
1024   StoreBaseIndexed(rs_dst, rs_length, rs_tmp, 0, kSignedHalf);
1025 
1026   // Copy two elements.
1027   LIR *begin_loop = NewLIR0(kPseudoTargetLabel);
1028   LIR* jmp_to_ret = OpCmpImmBranch(kCondEq, rs_length, 0, nullptr);
1029   OpRegImm(kOpSub, rs_length, 4);
1030   LoadBaseIndexed(rs_src, rs_length, rs_tmp, 0, k32);
1031   StoreBaseIndexed(rs_dst, rs_length, rs_tmp, 0, k32);
1032   OpUnconditionalBranch(begin_loop);
1033 
1034   LIR *check_failed = NewLIR0(kPseudoTargetLabel);
1035   LIR* launchpad_branch = OpUnconditionalBranch(nullptr);
1036   LIR* return_point = NewLIR0(kPseudoTargetLabel);
1037 
1038   src_check_branch->target = check_failed;
1039   dst_check_branch->target = check_failed;
1040   src_dst_same->target = check_failed;
1041   len_neg_or_too_big->target = check_failed;
1042   src_pos_negative->target = check_failed;
1043   src_bad_len->target = check_failed;
1044   dst_pos_negative->target = check_failed;
1045   dst_bad_len->target = check_failed;
1046   jmp_to_begin_loop->target = begin_loop;
1047   jmp_to_ret->target = return_point;
1048 
1049   AddIntrinsicSlowPath(info, launchpad_branch, return_point);
1050   ClobberCallerSave();  // We must clobber everything because slow path will return here
1051 
1052   return true;
1053 }
1054 
OpPcRelLoad(RegStorage reg,LIR * target)1055 LIR* ArmMir2Lir::OpPcRelLoad(RegStorage reg, LIR* target) {
1056   return RawLIR(current_dalvik_offset_, kThumb2LdrPcRel12, reg.GetReg(), 0, 0, 0, 0, target);
1057 }
1058 
OpVldm(RegStorage r_base,int count)1059 LIR* ArmMir2Lir::OpVldm(RegStorage r_base, int count) {
1060   return NewLIR3(kThumb2Vldms, r_base.GetReg(), rs_fr0.GetReg(), count);
1061 }
1062 
OpVstm(RegStorage r_base,int count)1063 LIR* ArmMir2Lir::OpVstm(RegStorage r_base, int count) {
1064   return NewLIR3(kThumb2Vstms, r_base.GetReg(), rs_fr0.GetReg(), count);
1065 }
1066 
GenMultiplyByTwoBitMultiplier(RegLocation rl_src,RegLocation rl_result,int lit,int first_bit,int second_bit)1067 void ArmMir2Lir::GenMultiplyByTwoBitMultiplier(RegLocation rl_src,
1068                                                RegLocation rl_result, int lit,
1069                                                int first_bit, int second_bit) {
1070   OpRegRegRegShift(kOpAdd, rl_result.reg, rl_src.reg, rl_src.reg,
1071                    EncodeShift(kArmLsl, second_bit - first_bit));
1072   if (first_bit != 0) {
1073     OpRegRegImm(kOpLsl, rl_result.reg, rl_result.reg, first_bit);
1074   }
1075 }
1076 
GenDivZeroCheckWide(RegStorage reg)1077 void ArmMir2Lir::GenDivZeroCheckWide(RegStorage reg) {
1078   DCHECK(reg.IsPair());   // TODO: support k64BitSolo.
1079   RegStorage t_reg = AllocTemp();
1080   NewLIR4(kThumb2OrrRRRs, t_reg.GetReg(), reg.GetLowReg(), reg.GetHighReg(), 0);
1081   FreeTemp(t_reg);
1082   GenDivZeroCheck(kCondEq);
1083 }
1084 
1085 // Test suspend flag, return target of taken suspend branch
OpTestSuspend(LIR * target)1086 LIR* ArmMir2Lir::OpTestSuspend(LIR* target) {
1087 #ifdef ARM_R4_SUSPEND_FLAG
1088   NewLIR2(kThumbSubRI8, rs_rARM_SUSPEND.GetReg(), 1);
1089   return OpCondBranch((target == NULL) ? kCondEq : kCondNe, target);
1090 #else
1091   RegStorage t_reg = AllocTemp();
1092   LoadBaseDisp(rs_rARM_SELF, Thread::ThreadFlagsOffset<4>().Int32Value(),
1093     t_reg, kUnsignedHalf);
1094   LIR* cmp_branch = OpCmpImmBranch((target == NULL) ? kCondNe : kCondEq, t_reg,
1095     0, target);
1096   FreeTemp(t_reg);
1097   return cmp_branch;
1098 #endif
1099 }
1100 
1101 // Decrement register and branch on condition
OpDecAndBranch(ConditionCode c_code,RegStorage reg,LIR * target)1102 LIR* ArmMir2Lir::OpDecAndBranch(ConditionCode c_code, RegStorage reg, LIR* target) {
1103   // Combine sub & test using sub setflags encoding here
1104   OpRegRegImm(kOpSub, reg, reg, 1);  // For value == 1, this should set flags.
1105   DCHECK(last_lir_insn_->u.m.def_mask->HasBit(ResourceMask::kCCode));
1106   return OpCondBranch(c_code, target);
1107 }
1108 
GenMemBarrier(MemBarrierKind barrier_kind)1109 bool ArmMir2Lir::GenMemBarrier(MemBarrierKind barrier_kind) {
1110 #if ANDROID_SMP != 0
1111   // Start off with using the last LIR as the barrier. If it is not enough, then we will generate one.
1112   LIR* barrier = last_lir_insn_;
1113 
1114   int dmb_flavor;
1115   // TODO: revisit Arm barrier kinds
1116   switch (barrier_kind) {
1117     case kAnyStore: dmb_flavor = kISH; break;
1118     case kLoadAny: dmb_flavor = kISH; break;
1119     case kStoreStore: dmb_flavor = kISHST; break;
1120     case kAnyAny: dmb_flavor = kISH; break;
1121     default:
1122       LOG(FATAL) << "Unexpected MemBarrierKind: " << barrier_kind;
1123       dmb_flavor = kSY;  // quiet gcc.
1124       break;
1125   }
1126 
1127   bool ret = false;
1128 
1129   // If the same barrier already exists, don't generate another.
1130   if (barrier == nullptr
1131       || (barrier != nullptr && (barrier->opcode != kThumb2Dmb || barrier->operands[0] != dmb_flavor))) {
1132     barrier = NewLIR1(kThumb2Dmb, dmb_flavor);
1133     ret = true;
1134   }
1135 
1136   // At this point we must have a memory barrier. Mark it as a scheduling barrier as well.
1137   DCHECK(!barrier->flags.use_def_invalid);
1138   barrier->u.m.def_mask = &kEncodeAll;
1139   return ret;
1140 #else
1141   return false;
1142 #endif
1143 }
1144 
GenNegLong(RegLocation rl_dest,RegLocation rl_src)1145 void ArmMir2Lir::GenNegLong(RegLocation rl_dest, RegLocation rl_src) {
1146   rl_src = LoadValueWide(rl_src, kCoreReg);
1147   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
1148   RegStorage z_reg = AllocTemp();
1149   LoadConstantNoClobber(z_reg, 0);
1150   // Check for destructive overlap
1151   if (rl_result.reg.GetLowReg() == rl_src.reg.GetHighReg()) {
1152     RegStorage t_reg = AllocTemp();
1153     OpRegCopy(t_reg, rl_result.reg.GetLow());
1154     OpRegRegReg(kOpSub, rl_result.reg.GetLow(), z_reg, rl_src.reg.GetLow());
1155     OpRegRegReg(kOpSbc, rl_result.reg.GetHigh(), z_reg, t_reg);
1156     FreeTemp(t_reg);
1157   } else {
1158     OpRegRegReg(kOpSub, rl_result.reg.GetLow(), z_reg, rl_src.reg.GetLow());
1159     OpRegRegReg(kOpSbc, rl_result.reg.GetHigh(), z_reg, rl_src.reg.GetHigh());
1160   }
1161   FreeTemp(z_reg);
1162   StoreValueWide(rl_dest, rl_result);
1163 }
1164 
GenMulLong(Instruction::Code opcode,RegLocation rl_dest,RegLocation rl_src1,RegLocation rl_src2)1165 void ArmMir2Lir::GenMulLong(Instruction::Code opcode, RegLocation rl_dest,
1166                             RegLocation rl_src1, RegLocation rl_src2) {
1167     /*
1168      * tmp1     = src1.hi * src2.lo;  // src1.hi is no longer needed
1169      * dest     = src1.lo * src2.lo;
1170      * tmp1    += src1.lo * src2.hi;
1171      * dest.hi += tmp1;
1172      *
1173      * To pull off inline multiply, we have a worst-case requirement of 7 temporary
1174      * registers.  Normally for Arm, we get 5.  We can get to 6 by including
1175      * lr in the temp set.  The only problematic case is all operands and result are
1176      * distinct, and none have been promoted.  In that case, we can succeed by aggressively
1177      * freeing operand temp registers after they are no longer needed.  All other cases
1178      * can proceed normally.  We'll just punt on the case of the result having a misaligned
1179      * overlap with either operand and send that case to a runtime handler.
1180      */
1181     RegLocation rl_result;
1182     if (BadOverlap(rl_src1, rl_dest) || (BadOverlap(rl_src2, rl_dest))) {
1183       FlushAllRegs();
1184       CallRuntimeHelperRegLocationRegLocation(kQuickLmul, rl_src1, rl_src2, false);
1185       rl_result = GetReturnWide(kCoreReg);
1186       StoreValueWide(rl_dest, rl_result);
1187       return;
1188     }
1189 
1190     rl_src1 = LoadValueWide(rl_src1, kCoreReg);
1191     rl_src2 = LoadValueWide(rl_src2, kCoreReg);
1192 
1193     int reg_status = 0;
1194     RegStorage res_lo;
1195     RegStorage res_hi;
1196     bool dest_promoted = rl_dest.location == kLocPhysReg && rl_dest.reg.Valid() &&
1197         !IsTemp(rl_dest.reg.GetLow()) && !IsTemp(rl_dest.reg.GetHigh());
1198     bool src1_promoted = !IsTemp(rl_src1.reg.GetLow()) && !IsTemp(rl_src1.reg.GetHigh());
1199     bool src2_promoted = !IsTemp(rl_src2.reg.GetLow()) && !IsTemp(rl_src2.reg.GetHigh());
1200     // Check if rl_dest is *not* either operand and we have enough temp registers.
1201     if ((rl_dest.s_reg_low != rl_src1.s_reg_low && rl_dest.s_reg_low != rl_src2.s_reg_low) &&
1202         (dest_promoted || src1_promoted || src2_promoted)) {
1203       // In this case, we do not need to manually allocate temp registers for result.
1204       rl_result = EvalLoc(rl_dest, kCoreReg, true);
1205       res_lo = rl_result.reg.GetLow();
1206       res_hi = rl_result.reg.GetHigh();
1207     } else {
1208       res_lo = AllocTemp();
1209       if ((rl_src1.s_reg_low == rl_src2.s_reg_low) || src1_promoted || src2_promoted) {
1210         // In this case, we have enough temp registers to be allocated for result.
1211         res_hi = AllocTemp();
1212         reg_status = 1;
1213       } else {
1214         // In this case, all temps are now allocated.
1215         // res_hi will be allocated after we can free src1_hi.
1216         reg_status = 2;
1217       }
1218     }
1219 
1220     // Temporarily add LR to the temp pool, and assign it to tmp1
1221     MarkTemp(rs_rARM_LR);
1222     FreeTemp(rs_rARM_LR);
1223     RegStorage tmp1 = rs_rARM_LR;
1224     LockTemp(rs_rARM_LR);
1225 
1226     if (rl_src1.reg == rl_src2.reg) {
1227       DCHECK(res_hi.Valid());
1228       DCHECK(res_lo.Valid());
1229       NewLIR3(kThumb2MulRRR, tmp1.GetReg(), rl_src1.reg.GetLowReg(), rl_src1.reg.GetHighReg());
1230       NewLIR4(kThumb2Umull, res_lo.GetReg(), res_hi.GetReg(), rl_src1.reg.GetLowReg(),
1231               rl_src1.reg.GetLowReg());
1232       OpRegRegRegShift(kOpAdd, res_hi, res_hi, tmp1, EncodeShift(kArmLsl, 1));
1233     } else {
1234       NewLIR3(kThumb2MulRRR, tmp1.GetReg(), rl_src2.reg.GetLowReg(), rl_src1.reg.GetHighReg());
1235       if (reg_status == 2) {
1236         DCHECK(!res_hi.Valid());
1237         DCHECK_NE(rl_src1.reg.GetLowReg(), rl_src2.reg.GetLowReg());
1238         DCHECK_NE(rl_src1.reg.GetHighReg(), rl_src2.reg.GetHighReg());
1239         // Will force free src1_hi, so must clobber.
1240         Clobber(rl_src1.reg);
1241         FreeTemp(rl_src1.reg.GetHigh());
1242         res_hi = AllocTemp();
1243       }
1244       DCHECK(res_hi.Valid());
1245       DCHECK(res_lo.Valid());
1246       NewLIR4(kThumb2Umull, res_lo.GetReg(), res_hi.GetReg(), rl_src2.reg.GetLowReg(),
1247               rl_src1.reg.GetLowReg());
1248       NewLIR4(kThumb2Mla, tmp1.GetReg(), rl_src1.reg.GetLowReg(), rl_src2.reg.GetHighReg(),
1249               tmp1.GetReg());
1250       NewLIR4(kThumb2AddRRR, res_hi.GetReg(), tmp1.GetReg(), res_hi.GetReg(), 0);
1251       if (reg_status == 2) {
1252         FreeTemp(rl_src1.reg.GetLow());
1253       }
1254     }
1255 
1256     // Now, restore lr to its non-temp status.
1257     FreeTemp(tmp1);
1258     Clobber(rs_rARM_LR);
1259     UnmarkTemp(rs_rARM_LR);
1260 
1261     if (reg_status != 0) {
1262       // We had manually allocated registers for rl_result.
1263       // Now construct a RegLocation.
1264       rl_result = GetReturnWide(kCoreReg);  // Just using as a template.
1265       rl_result.reg = RegStorage::MakeRegPair(res_lo, res_hi);
1266     }
1267 
1268     StoreValueWide(rl_dest, rl_result);
1269 }
1270 
GenArithOpLong(Instruction::Code opcode,RegLocation rl_dest,RegLocation rl_src1,RegLocation rl_src2)1271 void ArmMir2Lir::GenArithOpLong(Instruction::Code opcode, RegLocation rl_dest, RegLocation rl_src1,
1272                                 RegLocation rl_src2) {
1273   switch (opcode) {
1274     case Instruction::MUL_LONG:
1275     case Instruction::MUL_LONG_2ADDR:
1276       GenMulLong(opcode, rl_dest, rl_src1, rl_src2);
1277       return;
1278     case Instruction::NEG_LONG:
1279       GenNegLong(rl_dest, rl_src2);
1280       return;
1281 
1282     default:
1283       break;
1284   }
1285 
1286   // Fallback for all other ops.
1287   Mir2Lir::GenArithOpLong(opcode, rl_dest, rl_src1, rl_src2);
1288 }
1289 
1290 /*
1291  * Generate array load
1292  */
GenArrayGet(int opt_flags,OpSize size,RegLocation rl_array,RegLocation rl_index,RegLocation rl_dest,int scale)1293 void ArmMir2Lir::GenArrayGet(int opt_flags, OpSize size, RegLocation rl_array,
1294                              RegLocation rl_index, RegLocation rl_dest, int scale) {
1295   RegisterClass reg_class = RegClassBySize(size);
1296   int len_offset = mirror::Array::LengthOffset().Int32Value();
1297   int data_offset;
1298   RegLocation rl_result;
1299   bool constant_index = rl_index.is_const;
1300   rl_array = LoadValue(rl_array, kRefReg);
1301   if (!constant_index) {
1302     rl_index = LoadValue(rl_index, kCoreReg);
1303   }
1304 
1305   if (rl_dest.wide) {
1306     data_offset = mirror::Array::DataOffset(sizeof(int64_t)).Int32Value();
1307   } else {
1308     data_offset = mirror::Array::DataOffset(sizeof(int32_t)).Int32Value();
1309   }
1310 
1311   // If index is constant, just fold it into the data offset
1312   if (constant_index) {
1313     data_offset += mir_graph_->ConstantValue(rl_index) << scale;
1314   }
1315 
1316   /* null object? */
1317   GenNullCheck(rl_array.reg, opt_flags);
1318 
1319   bool needs_range_check = (!(opt_flags & MIR_IGNORE_RANGE_CHECK));
1320   RegStorage reg_len;
1321   if (needs_range_check) {
1322     reg_len = AllocTemp();
1323     /* Get len */
1324     Load32Disp(rl_array.reg, len_offset, reg_len);
1325     MarkPossibleNullPointerException(opt_flags);
1326   } else {
1327     ForceImplicitNullCheck(rl_array.reg, opt_flags);
1328   }
1329   if (rl_dest.wide || rl_dest.fp || constant_index) {
1330     RegStorage reg_ptr;
1331     if (constant_index) {
1332       reg_ptr = rl_array.reg;  // NOTE: must not alter reg_ptr in constant case.
1333     } else {
1334       // No special indexed operation, lea + load w/ displacement
1335       reg_ptr = AllocTempRef();
1336       OpRegRegRegShift(kOpAdd, reg_ptr, rl_array.reg, rl_index.reg, EncodeShift(kArmLsl, scale));
1337       FreeTemp(rl_index.reg);
1338     }
1339     rl_result = EvalLoc(rl_dest, reg_class, true);
1340 
1341     if (needs_range_check) {
1342       if (constant_index) {
1343         GenArrayBoundsCheck(mir_graph_->ConstantValue(rl_index), reg_len);
1344       } else {
1345         GenArrayBoundsCheck(rl_index.reg, reg_len);
1346       }
1347       FreeTemp(reg_len);
1348     }
1349     LoadBaseDisp(reg_ptr, data_offset, rl_result.reg, size, kNotVolatile);
1350     MarkPossibleNullPointerException(opt_flags);
1351     if (!constant_index) {
1352       FreeTemp(reg_ptr);
1353     }
1354     if (rl_dest.wide) {
1355       StoreValueWide(rl_dest, rl_result);
1356     } else {
1357       StoreValue(rl_dest, rl_result);
1358     }
1359   } else {
1360     // Offset base, then use indexed load
1361     RegStorage reg_ptr = AllocTempRef();
1362     OpRegRegImm(kOpAdd, reg_ptr, rl_array.reg, data_offset);
1363     FreeTemp(rl_array.reg);
1364     rl_result = EvalLoc(rl_dest, reg_class, true);
1365 
1366     if (needs_range_check) {
1367       GenArrayBoundsCheck(rl_index.reg, reg_len);
1368       FreeTemp(reg_len);
1369     }
1370     LoadBaseIndexed(reg_ptr, rl_index.reg, rl_result.reg, scale, size);
1371     MarkPossibleNullPointerException(opt_flags);
1372     FreeTemp(reg_ptr);
1373     StoreValue(rl_dest, rl_result);
1374   }
1375 }
1376 
1377 /*
1378  * Generate array store
1379  *
1380  */
GenArrayPut(int opt_flags,OpSize size,RegLocation rl_array,RegLocation rl_index,RegLocation rl_src,int scale,bool card_mark)1381 void ArmMir2Lir::GenArrayPut(int opt_flags, OpSize size, RegLocation rl_array,
1382                              RegLocation rl_index, RegLocation rl_src, int scale, bool card_mark) {
1383   RegisterClass reg_class = RegClassBySize(size);
1384   int len_offset = mirror::Array::LengthOffset().Int32Value();
1385   bool constant_index = rl_index.is_const;
1386 
1387   int data_offset;
1388   if (size == k64 || size == kDouble) {
1389     data_offset = mirror::Array::DataOffset(sizeof(int64_t)).Int32Value();
1390   } else {
1391     data_offset = mirror::Array::DataOffset(sizeof(int32_t)).Int32Value();
1392   }
1393 
1394   // If index is constant, just fold it into the data offset.
1395   if (constant_index) {
1396     data_offset += mir_graph_->ConstantValue(rl_index) << scale;
1397   }
1398 
1399   rl_array = LoadValue(rl_array, kRefReg);
1400   if (!constant_index) {
1401     rl_index = LoadValue(rl_index, kCoreReg);
1402   }
1403 
1404   RegStorage reg_ptr;
1405   bool allocated_reg_ptr_temp = false;
1406   if (constant_index) {
1407     reg_ptr = rl_array.reg;
1408   } else if (IsTemp(rl_array.reg) && !card_mark) {
1409     Clobber(rl_array.reg);
1410     reg_ptr = rl_array.reg;
1411   } else {
1412     allocated_reg_ptr_temp = true;
1413     reg_ptr = AllocTempRef();
1414   }
1415 
1416   /* null object? */
1417   GenNullCheck(rl_array.reg, opt_flags);
1418 
1419   bool needs_range_check = (!(opt_flags & MIR_IGNORE_RANGE_CHECK));
1420   RegStorage reg_len;
1421   if (needs_range_check) {
1422     reg_len = AllocTemp();
1423     // NOTE: max live temps(4) here.
1424     /* Get len */
1425     Load32Disp(rl_array.reg, len_offset, reg_len);
1426     MarkPossibleNullPointerException(opt_flags);
1427   } else {
1428     ForceImplicitNullCheck(rl_array.reg, opt_flags);
1429   }
1430   /* at this point, reg_ptr points to array, 2 live temps */
1431   if (rl_src.wide || rl_src.fp || constant_index) {
1432     if (rl_src.wide) {
1433       rl_src = LoadValueWide(rl_src, reg_class);
1434     } else {
1435       rl_src = LoadValue(rl_src, reg_class);
1436     }
1437     if (!constant_index) {
1438       OpRegRegRegShift(kOpAdd, reg_ptr, rl_array.reg, rl_index.reg, EncodeShift(kArmLsl, scale));
1439     }
1440     if (needs_range_check) {
1441       if (constant_index) {
1442         GenArrayBoundsCheck(mir_graph_->ConstantValue(rl_index), reg_len);
1443       } else {
1444         GenArrayBoundsCheck(rl_index.reg, reg_len);
1445       }
1446       FreeTemp(reg_len);
1447     }
1448 
1449     StoreBaseDisp(reg_ptr, data_offset, rl_src.reg, size, kNotVolatile);
1450     MarkPossibleNullPointerException(opt_flags);
1451   } else {
1452     /* reg_ptr -> array data */
1453     OpRegRegImm(kOpAdd, reg_ptr, rl_array.reg, data_offset);
1454     rl_src = LoadValue(rl_src, reg_class);
1455     if (needs_range_check) {
1456       GenArrayBoundsCheck(rl_index.reg, reg_len);
1457       FreeTemp(reg_len);
1458     }
1459     StoreBaseIndexed(reg_ptr, rl_index.reg, rl_src.reg, scale, size);
1460     MarkPossibleNullPointerException(opt_flags);
1461   }
1462   if (allocated_reg_ptr_temp) {
1463     FreeTemp(reg_ptr);
1464   }
1465   if (card_mark) {
1466     MarkGCCard(rl_src.reg, rl_array.reg);
1467   }
1468 }
1469 
1470 
GenShiftImmOpLong(Instruction::Code opcode,RegLocation rl_dest,RegLocation rl_src,RegLocation rl_shift)1471 void ArmMir2Lir::GenShiftImmOpLong(Instruction::Code opcode,
1472                                    RegLocation rl_dest, RegLocation rl_src, RegLocation rl_shift) {
1473   rl_src = LoadValueWide(rl_src, kCoreReg);
1474   // Per spec, we only care about low 6 bits of shift amount.
1475   int shift_amount = mir_graph_->ConstantValue(rl_shift) & 0x3f;
1476   if (shift_amount == 0) {
1477     StoreValueWide(rl_dest, rl_src);
1478     return;
1479   }
1480   if (BadOverlap(rl_src, rl_dest)) {
1481     GenShiftOpLong(opcode, rl_dest, rl_src, rl_shift);
1482     return;
1483   }
1484   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
1485   switch (opcode) {
1486     case Instruction::SHL_LONG:
1487     case Instruction::SHL_LONG_2ADDR:
1488       if (shift_amount == 1) {
1489         OpRegRegReg(kOpAdd, rl_result.reg.GetLow(), rl_src.reg.GetLow(), rl_src.reg.GetLow());
1490         OpRegRegReg(kOpAdc, rl_result.reg.GetHigh(), rl_src.reg.GetHigh(), rl_src.reg.GetHigh());
1491       } else if (shift_amount == 32) {
1492         OpRegCopy(rl_result.reg.GetHigh(), rl_src.reg);
1493         LoadConstant(rl_result.reg.GetLow(), 0);
1494       } else if (shift_amount > 31) {
1495         OpRegRegImm(kOpLsl, rl_result.reg.GetHigh(), rl_src.reg.GetLow(), shift_amount - 32);
1496         LoadConstant(rl_result.reg.GetLow(), 0);
1497       } else {
1498         OpRegRegImm(kOpLsl, rl_result.reg.GetHigh(), rl_src.reg.GetHigh(), shift_amount);
1499         OpRegRegRegShift(kOpOr, rl_result.reg.GetHigh(), rl_result.reg.GetHigh(), rl_src.reg.GetLow(),
1500                          EncodeShift(kArmLsr, 32 - shift_amount));
1501         OpRegRegImm(kOpLsl, rl_result.reg.GetLow(), rl_src.reg.GetLow(), shift_amount);
1502       }
1503       break;
1504     case Instruction::SHR_LONG:
1505     case Instruction::SHR_LONG_2ADDR:
1506       if (shift_amount == 32) {
1507         OpRegCopy(rl_result.reg.GetLow(), rl_src.reg.GetHigh());
1508         OpRegRegImm(kOpAsr, rl_result.reg.GetHigh(), rl_src.reg.GetHigh(), 31);
1509       } else if (shift_amount > 31) {
1510         OpRegRegImm(kOpAsr, rl_result.reg.GetLow(), rl_src.reg.GetHigh(), shift_amount - 32);
1511         OpRegRegImm(kOpAsr, rl_result.reg.GetHigh(), rl_src.reg.GetHigh(), 31);
1512       } else {
1513         RegStorage t_reg = AllocTemp();
1514         OpRegRegImm(kOpLsr, t_reg, rl_src.reg.GetLow(), shift_amount);
1515         OpRegRegRegShift(kOpOr, rl_result.reg.GetLow(), t_reg, rl_src.reg.GetHigh(),
1516                          EncodeShift(kArmLsl, 32 - shift_amount));
1517         FreeTemp(t_reg);
1518         OpRegRegImm(kOpAsr, rl_result.reg.GetHigh(), rl_src.reg.GetHigh(), shift_amount);
1519       }
1520       break;
1521     case Instruction::USHR_LONG:
1522     case Instruction::USHR_LONG_2ADDR:
1523       if (shift_amount == 32) {
1524         OpRegCopy(rl_result.reg.GetLow(), rl_src.reg.GetHigh());
1525         LoadConstant(rl_result.reg.GetHigh(), 0);
1526       } else if (shift_amount > 31) {
1527         OpRegRegImm(kOpLsr, rl_result.reg.GetLow(), rl_src.reg.GetHigh(), shift_amount - 32);
1528         LoadConstant(rl_result.reg.GetHigh(), 0);
1529       } else {
1530         RegStorage t_reg = AllocTemp();
1531         OpRegRegImm(kOpLsr, t_reg, rl_src.reg.GetLow(), shift_amount);
1532         OpRegRegRegShift(kOpOr, rl_result.reg.GetLow(), t_reg, rl_src.reg.GetHigh(),
1533                          EncodeShift(kArmLsl, 32 - shift_amount));
1534         FreeTemp(t_reg);
1535         OpRegRegImm(kOpLsr, rl_result.reg.GetHigh(), rl_src.reg.GetHigh(), shift_amount);
1536       }
1537       break;
1538     default:
1539       LOG(FATAL) << "Unexpected case";
1540   }
1541   StoreValueWide(rl_dest, rl_result);
1542 }
1543 
GenArithImmOpLong(Instruction::Code opcode,RegLocation rl_dest,RegLocation rl_src1,RegLocation rl_src2)1544 void ArmMir2Lir::GenArithImmOpLong(Instruction::Code opcode,
1545                                    RegLocation rl_dest, RegLocation rl_src1, RegLocation rl_src2) {
1546   if ((opcode == Instruction::SUB_LONG_2ADDR) || (opcode == Instruction::SUB_LONG)) {
1547     if (!rl_src2.is_const) {
1548       // Don't bother with special handling for subtract from immediate.
1549       GenArithOpLong(opcode, rl_dest, rl_src1, rl_src2);
1550       return;
1551     }
1552   } else {
1553     // Normalize
1554     if (!rl_src2.is_const) {
1555       DCHECK(rl_src1.is_const);
1556       std::swap(rl_src1, rl_src2);
1557     }
1558   }
1559   if (BadOverlap(rl_src1, rl_dest)) {
1560     GenArithOpLong(opcode, rl_dest, rl_src1, rl_src2);
1561     return;
1562   }
1563   DCHECK(rl_src2.is_const);
1564   int64_t val = mir_graph_->ConstantValueWide(rl_src2);
1565   uint32_t val_lo = Low32Bits(val);
1566   uint32_t val_hi = High32Bits(val);
1567   int32_t mod_imm_lo = ModifiedImmediate(val_lo);
1568   int32_t mod_imm_hi = ModifiedImmediate(val_hi);
1569 
1570   // Only a subset of add/sub immediate instructions set carry - so bail if we don't fit
1571   switch (opcode) {
1572     case Instruction::ADD_LONG:
1573     case Instruction::ADD_LONG_2ADDR:
1574     case Instruction::SUB_LONG:
1575     case Instruction::SUB_LONG_2ADDR:
1576       if ((mod_imm_lo < 0) || (mod_imm_hi < 0)) {
1577         GenArithOpLong(opcode, rl_dest, rl_src1, rl_src2);
1578         return;
1579       }
1580       break;
1581     default:
1582       break;
1583   }
1584   rl_src1 = LoadValueWide(rl_src1, kCoreReg);
1585   RegLocation rl_result = EvalLoc(rl_dest, kCoreReg, true);
1586   // NOTE: once we've done the EvalLoc on dest, we can no longer bail.
1587   switch (opcode) {
1588     case Instruction::ADD_LONG:
1589     case Instruction::ADD_LONG_2ADDR:
1590       NewLIR3(kThumb2AddRRI8M, rl_result.reg.GetLowReg(), rl_src1.reg.GetLowReg(), mod_imm_lo);
1591       NewLIR3(kThumb2AdcRRI8M, rl_result.reg.GetHighReg(), rl_src1.reg.GetHighReg(), mod_imm_hi);
1592       break;
1593     case Instruction::OR_LONG:
1594     case Instruction::OR_LONG_2ADDR:
1595       if ((val_lo != 0) || (rl_result.reg.GetLowReg() != rl_src1.reg.GetLowReg())) {
1596         OpRegRegImm(kOpOr, rl_result.reg.GetLow(), rl_src1.reg.GetLow(), val_lo);
1597       }
1598       if ((val_hi != 0) || (rl_result.reg.GetHighReg() != rl_src1.reg.GetHighReg())) {
1599         OpRegRegImm(kOpOr, rl_result.reg.GetHigh(), rl_src1.reg.GetHigh(), val_hi);
1600       }
1601       break;
1602     case Instruction::XOR_LONG:
1603     case Instruction::XOR_LONG_2ADDR:
1604       OpRegRegImm(kOpXor, rl_result.reg.GetLow(), rl_src1.reg.GetLow(), val_lo);
1605       OpRegRegImm(kOpXor, rl_result.reg.GetHigh(), rl_src1.reg.GetHigh(), val_hi);
1606       break;
1607     case Instruction::AND_LONG:
1608     case Instruction::AND_LONG_2ADDR:
1609       if ((val_lo != 0xffffffff) || (rl_result.reg.GetLowReg() != rl_src1.reg.GetLowReg())) {
1610         OpRegRegImm(kOpAnd, rl_result.reg.GetLow(), rl_src1.reg.GetLow(), val_lo);
1611       }
1612       if ((val_hi != 0xffffffff) || (rl_result.reg.GetHighReg() != rl_src1.reg.GetHighReg())) {
1613         OpRegRegImm(kOpAnd, rl_result.reg.GetHigh(), rl_src1.reg.GetHigh(), val_hi);
1614       }
1615       break;
1616     case Instruction::SUB_LONG_2ADDR:
1617     case Instruction::SUB_LONG:
1618       NewLIR3(kThumb2SubRRI8M, rl_result.reg.GetLowReg(), rl_src1.reg.GetLowReg(), mod_imm_lo);
1619       NewLIR3(kThumb2SbcRRI8M, rl_result.reg.GetHighReg(), rl_src1.reg.GetHighReg(), mod_imm_hi);
1620       break;
1621     default:
1622       LOG(FATAL) << "Unexpected opcode " << opcode;
1623   }
1624   StoreValueWide(rl_dest, rl_result);
1625 }
1626 
1627 }  // namespace art
1628