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 #ifndef ART_COMPILER_COMPILED_METHOD_H_
18 #define ART_COMPILER_COMPILED_METHOD_H_
19 
20 #include <memory>
21 #include <string>
22 #include <vector>
23 
24 #include "arch/instruction_set.h"
25 #include "base/bit_utils.h"
26 #include "method_reference.h"
27 #include "utils/array_ref.h"
28 #include "utils/swap_space.h"
29 
30 namespace art {
31 
32 class CompilerDriver;
33 
34 class CompiledCode {
35  public:
36   // For Quick to supply an code blob
37   CompiledCode(CompilerDriver* compiler_driver, InstructionSet instruction_set,
38                const ArrayRef<const uint8_t>& quick_code, bool owns_code_array);
39 
40   virtual ~CompiledCode();
41 
GetInstructionSet()42   InstructionSet GetInstructionSet() const {
43     return instruction_set_;
44   }
45 
GetQuickCode()46   const SwapVector<uint8_t>* GetQuickCode() const {
47     return quick_code_;
48   }
49 
50   void SetCode(const ArrayRef<const uint8_t>* quick_code);
51 
52   bool operator==(const CompiledCode& rhs) const;
53 
54   // To align an offset from a page-aligned value to make it suitable
55   // for code storage. For example on ARM, to ensure that PC relative
56   // valu computations work out as expected.
57   size_t AlignCode(size_t offset) const;
58   static size_t AlignCode(size_t offset, InstructionSet instruction_set);
59 
60   // returns the difference between the code address and a usable PC.
61   // mainly to cope with kThumb2 where the lower bit must be set.
62   size_t CodeDelta() const;
63   static size_t CodeDelta(InstructionSet instruction_set);
64 
65   // Returns a pointer suitable for invoking the code at the argument
66   // code_pointer address.  Mainly to cope with kThumb2 where the
67   // lower bit must be set to indicate Thumb mode.
68   static const void* CodePointer(const void* code_pointer,
69                                  InstructionSet instruction_set);
70 
71   const std::vector<uint32_t>& GetOatdataOffsetsToCompliledCodeOffset() const;
72   void AddOatdataOffsetToCompliledCodeOffset(uint32_t offset);
73 
74  private:
75   CompilerDriver* const compiler_driver_;
76 
77   const InstructionSet instruction_set_;
78 
79   // If we own the code array (means that we free in destructor).
80   const bool owns_code_array_;
81 
82   // Used to store the PIC code for Quick.
83   SwapVector<uint8_t>* quick_code_;
84 
85   // There are offsets from the oatdata symbol to where the offset to
86   // the compiled method will be found. These are computed by the
87   // OatWriter and then used by the ElfWriter to add relocations so
88   // that MCLinker can update the values to the location in the linked .so.
89   std::vector<uint32_t> oatdata_offsets_to_compiled_code_offset_;
90 };
91 
92 class SrcMapElem {
93  public:
94   uint32_t from_;
95   int32_t to_;
96 
97   // Lexicographical compare.
98   bool operator<(const SrcMapElem& other) const {
99     if (from_ != other.from_) {
100       return from_ < other.from_;
101     }
102     return to_ < other.to_;
103   }
104 };
105 
106 template <class Allocator>
107 class SrcMap FINAL : public std::vector<SrcMapElem, Allocator> {
108  public:
109   using std::vector<SrcMapElem, Allocator>::begin;
110   using typename std::vector<SrcMapElem, Allocator>::const_iterator;
111   using std::vector<SrcMapElem, Allocator>::empty;
112   using std::vector<SrcMapElem, Allocator>::end;
113   using std::vector<SrcMapElem, Allocator>::resize;
114   using std::vector<SrcMapElem, Allocator>::shrink_to_fit;
115   using std::vector<SrcMapElem, Allocator>::size;
116 
SrcMap()117   explicit SrcMap() {}
SrcMap(const Allocator & alloc)118   explicit SrcMap(const Allocator& alloc) : std::vector<SrcMapElem, Allocator>(alloc) {}
119 
120   template <class InputIt>
SrcMap(InputIt first,InputIt last,const Allocator & alloc)121   SrcMap(InputIt first, InputIt last, const Allocator& alloc)
122       : std::vector<SrcMapElem, Allocator>(first, last, alloc) {}
123 
push_back(const SrcMapElem & elem)124   void push_back(const SrcMapElem& elem) {
125     if (!empty()) {
126       // Check that the addresses are inserted in sorted order.
127       DCHECK_GE(elem.from_, this->back().from_);
128       // If two consequitive entries map to the same value, ignore the later.
129       // E.g. for map {{0, 1}, {4, 1}, {8, 2}}, all values in [0,8) map to 1.
130       if (elem.to_ == this->back().to_) {
131         return;
132       }
133     }
134     std::vector<SrcMapElem, Allocator>::push_back(elem);
135   }
136 
137   // Returns true and the corresponding "to" value if the mapping is found.
138   // Oterwise returns false and 0.
Find(uint32_t from)139   std::pair<bool, int32_t> Find(uint32_t from) const {
140     // Finds first mapping such that lb.from_ >= from.
141     auto lb = std::lower_bound(begin(), end(), SrcMapElem {from, INT32_MIN});
142     if (lb != end() && lb->from_ == from) {
143       // Found exact match.
144       return std::make_pair(true, lb->to_);
145     } else if (lb != begin()) {
146       // The previous mapping is still in effect.
147       return std::make_pair(true, (--lb)->to_);
148     } else {
149       // Not found because 'from' is smaller than first entry in the map.
150       return std::make_pair(false, 0);
151     }
152   }
153 };
154 
155 using DefaultSrcMap = SrcMap<std::allocator<SrcMapElem>>;
156 using SwapSrcMap = SrcMap<SwapAllocator<SrcMapElem>>;
157 
158 
159 enum LinkerPatchType {
160   kLinkerPatchMethod,
161   kLinkerPatchCall,
162   kLinkerPatchCallRelative,  // NOTE: Actual patching is instruction_set-dependent.
163   kLinkerPatchType,
164   kLinkerPatchDexCacheArray,  // NOTE: Actual patching is instruction_set-dependent.
165 };
166 
167 class LinkerPatch {
168  public:
MethodPatch(size_t literal_offset,const DexFile * target_dex_file,uint32_t target_method_idx)169   static LinkerPatch MethodPatch(size_t literal_offset,
170                                  const DexFile* target_dex_file,
171                                  uint32_t target_method_idx) {
172     LinkerPatch patch(literal_offset, kLinkerPatchMethod, target_dex_file);
173     patch.method_idx_ = target_method_idx;
174     return patch;
175   }
176 
CodePatch(size_t literal_offset,const DexFile * target_dex_file,uint32_t target_method_idx)177   static LinkerPatch CodePatch(size_t literal_offset,
178                                const DexFile* target_dex_file,
179                                uint32_t target_method_idx) {
180     LinkerPatch patch(literal_offset, kLinkerPatchCall, target_dex_file);
181     patch.method_idx_ = target_method_idx;
182     return patch;
183   }
184 
RelativeCodePatch(size_t literal_offset,const DexFile * target_dex_file,uint32_t target_method_idx)185   static LinkerPatch RelativeCodePatch(size_t literal_offset,
186                                        const DexFile* target_dex_file,
187                                        uint32_t target_method_idx) {
188     LinkerPatch patch(literal_offset, kLinkerPatchCallRelative, target_dex_file);
189     patch.method_idx_ = target_method_idx;
190     return patch;
191   }
192 
TypePatch(size_t literal_offset,const DexFile * target_dex_file,uint32_t target_type_idx)193   static LinkerPatch TypePatch(size_t literal_offset,
194                                const DexFile* target_dex_file,
195                                uint32_t target_type_idx) {
196     LinkerPatch patch(literal_offset, kLinkerPatchType, target_dex_file);
197     patch.type_idx_ = target_type_idx;
198     return patch;
199   }
200 
DexCacheArrayPatch(size_t literal_offset,const DexFile * target_dex_file,uint32_t pc_insn_offset,size_t element_offset)201   static LinkerPatch DexCacheArrayPatch(size_t literal_offset,
202                                         const DexFile* target_dex_file,
203                                         uint32_t pc_insn_offset,
204                                         size_t element_offset) {
205     DCHECK(IsUint<32>(element_offset));
206     LinkerPatch patch(literal_offset, kLinkerPatchDexCacheArray, target_dex_file);
207     patch.pc_insn_offset_ = pc_insn_offset;
208     patch.element_offset_ = element_offset;
209     return patch;
210   }
211 
212   LinkerPatch(const LinkerPatch& other) = default;
213   LinkerPatch& operator=(const LinkerPatch& other) = default;
214 
LiteralOffset()215   size_t LiteralOffset() const {
216     return literal_offset_;
217   }
218 
Type()219   LinkerPatchType Type() const {
220     return patch_type_;
221   }
222 
IsPcRelative()223   bool IsPcRelative() const {
224     return Type() == kLinkerPatchCallRelative || Type() == kLinkerPatchDexCacheArray;
225   }
226 
TargetMethod()227   MethodReference TargetMethod() const {
228     DCHECK(patch_type_ == kLinkerPatchMethod ||
229            patch_type_ == kLinkerPatchCall || patch_type_ == kLinkerPatchCallRelative);
230     return MethodReference(target_dex_file_, method_idx_);
231   }
232 
TargetTypeDexFile()233   const DexFile* TargetTypeDexFile() const {
234     DCHECK(patch_type_ == kLinkerPatchType);
235     return target_dex_file_;
236   }
237 
TargetTypeIndex()238   uint32_t TargetTypeIndex() const {
239     DCHECK(patch_type_ == kLinkerPatchType);
240     return type_idx_;
241   }
242 
TargetDexCacheDexFile()243   const DexFile* TargetDexCacheDexFile() const {
244     DCHECK(patch_type_ == kLinkerPatchDexCacheArray);
245     return target_dex_file_;
246   }
247 
TargetDexCacheElementOffset()248   size_t TargetDexCacheElementOffset() const {
249     DCHECK(patch_type_ == kLinkerPatchDexCacheArray);
250     return element_offset_;
251   }
252 
PcInsnOffset()253   uint32_t PcInsnOffset() const {
254     DCHECK(patch_type_ == kLinkerPatchDexCacheArray);
255     return pc_insn_offset_;
256   }
257 
258  private:
LinkerPatch(size_t literal_offset,LinkerPatchType patch_type,const DexFile * target_dex_file)259   LinkerPatch(size_t literal_offset, LinkerPatchType patch_type, const DexFile* target_dex_file)
260       : target_dex_file_(target_dex_file),
261         literal_offset_(literal_offset),
262         patch_type_(patch_type) {
263     cmp1_ = 0u;
264     cmp2_ = 0u;
265     // The compiler rejects methods that are too big, so the compiled code
266     // of a single method really shouln't be anywhere close to 16MiB.
267     DCHECK(IsUint<24>(literal_offset));
268   }
269 
270   const DexFile* target_dex_file_;
271   uint32_t literal_offset_ : 24;  // Method code size up to 16MiB.
272   LinkerPatchType patch_type_ : 8;
273   union {
274     uint32_t cmp1_;             // Used for relational operators.
275     uint32_t method_idx_;       // Method index for Call/Method patches.
276     uint32_t type_idx_;         // Type index for Type patches.
277     uint32_t element_offset_;   // Element offset in the dex cache arrays.
278   };
279   union {
280     uint32_t cmp2_;             // Used for relational operators.
281     // Literal offset of the insn loading PC (same as literal_offset if it's the same insn,
282     // may be different if the PC-relative addressing needs multiple insns).
283     uint32_t pc_insn_offset_;
284     static_assert(sizeof(pc_insn_offset_) == sizeof(cmp2_), "needed by relational operators");
285   };
286 
287   friend bool operator==(const LinkerPatch& lhs, const LinkerPatch& rhs);
288   friend bool operator<(const LinkerPatch& lhs, const LinkerPatch& rhs);
289 };
290 
291 inline bool operator==(const LinkerPatch& lhs, const LinkerPatch& rhs) {
292   return lhs.literal_offset_ == rhs.literal_offset_ &&
293       lhs.patch_type_ == rhs.patch_type_ &&
294       lhs.target_dex_file_ == rhs.target_dex_file_ &&
295       lhs.cmp1_ == rhs.cmp1_ &&
296       lhs.cmp2_ == rhs.cmp2_;
297 }
298 
299 inline bool operator<(const LinkerPatch& lhs, const LinkerPatch& rhs) {
300   return (lhs.literal_offset_ != rhs.literal_offset_) ? lhs.literal_offset_ < rhs.literal_offset_
301       : (lhs.patch_type_ != rhs.patch_type_) ? lhs.patch_type_ < rhs.patch_type_
302       : (lhs.target_dex_file_ != rhs.target_dex_file_) ? lhs.target_dex_file_ < rhs.target_dex_file_
303       : (lhs.cmp1_ != rhs.cmp1_) ? lhs.cmp1_ < rhs.cmp1_
304       : lhs.cmp2_ < rhs.cmp2_;
305 }
306 
307 class CompiledMethod FINAL : public CompiledCode {
308  public:
309   // Constructs a CompiledMethod.
310   // Note: Consider using the static allocation methods below that will allocate the CompiledMethod
311   //       in the swap space.
312   CompiledMethod(CompilerDriver* driver,
313                  InstructionSet instruction_set,
314                  const ArrayRef<const uint8_t>& quick_code,
315                  const size_t frame_size_in_bytes,
316                  const uint32_t core_spill_mask,
317                  const uint32_t fp_spill_mask,
318                  DefaultSrcMap* src_mapping_table,
319                  const ArrayRef<const uint8_t>& mapping_table,
320                  const ArrayRef<const uint8_t>& vmap_table,
321                  const ArrayRef<const uint8_t>& native_gc_map,
322                  const ArrayRef<const uint8_t>& cfi_info,
323                  const ArrayRef<const LinkerPatch>& patches);
324 
325   virtual ~CompiledMethod();
326 
327   static CompiledMethod* SwapAllocCompiledMethod(
328       CompilerDriver* driver,
329       InstructionSet instruction_set,
330       const ArrayRef<const uint8_t>& quick_code,
331       const size_t frame_size_in_bytes,
332       const uint32_t core_spill_mask,
333       const uint32_t fp_spill_mask,
334       DefaultSrcMap* src_mapping_table,
335       const ArrayRef<const uint8_t>& mapping_table,
336       const ArrayRef<const uint8_t>& vmap_table,
337       const ArrayRef<const uint8_t>& native_gc_map,
338       const ArrayRef<const uint8_t>& cfi_info,
339       const ArrayRef<const LinkerPatch>& patches);
340 
341   static void ReleaseSwapAllocatedCompiledMethod(CompilerDriver* driver, CompiledMethod* m);
342 
GetFrameSizeInBytes()343   size_t GetFrameSizeInBytes() const {
344     return frame_size_in_bytes_;
345   }
346 
GetCoreSpillMask()347   uint32_t GetCoreSpillMask() const {
348     return core_spill_mask_;
349   }
350 
GetFpSpillMask()351   uint32_t GetFpSpillMask() const {
352     return fp_spill_mask_;
353   }
354 
GetSrcMappingTable()355   const SwapSrcMap& GetSrcMappingTable() const {
356     DCHECK(src_mapping_table_ != nullptr);
357     return *src_mapping_table_;
358   }
359 
GetMappingTable()360   SwapVector<uint8_t> const* GetMappingTable() const {
361     return mapping_table_;
362   }
363 
GetVmapTable()364   const SwapVector<uint8_t>* GetVmapTable() const {
365     DCHECK(vmap_table_ != nullptr);
366     return vmap_table_;
367   }
368 
GetGcMap()369   SwapVector<uint8_t> const* GetGcMap() const {
370     return gc_map_;
371   }
372 
GetCFIInfo()373   const SwapVector<uint8_t>* GetCFIInfo() const {
374     return cfi_info_;
375   }
376 
GetPatches()377   ArrayRef<const LinkerPatch> GetPatches() const {
378     return ArrayRef<const LinkerPatch>(patches_);
379   }
380 
381  private:
382   // Whether or not the arrays are owned by the compiled method or dedupe sets.
383   const bool owns_arrays_;
384   // For quick code, the size of the activation used by the code.
385   const size_t frame_size_in_bytes_;
386   // For quick code, a bit mask describing spilled GPR callee-save registers.
387   const uint32_t core_spill_mask_;
388   // For quick code, a bit mask describing spilled FPR callee-save registers.
389   const uint32_t fp_spill_mask_;
390   // For quick code, a set of pairs (PC, DEX) mapping from native PC offset to DEX offset.
391   SwapSrcMap* src_mapping_table_;
392   // For quick code, a uleb128 encoded map from native PC offset to dex PC aswell as dex PC to
393   // native PC offset. Size prefixed.
394   SwapVector<uint8_t>* mapping_table_;
395   // For quick code, a uleb128 encoded map from GPR/FPR register to dex register. Size prefixed.
396   SwapVector<uint8_t>* vmap_table_;
397   // For quick code, a map keyed by native PC indices to bitmaps describing what dalvik registers
398   // are live.
399   SwapVector<uint8_t>* gc_map_;
400   // For quick code, a FDE entry for the debug_frame section.
401   SwapVector<uint8_t>* cfi_info_;
402   // For quick code, linker patches needed by the method.
403   const SwapVector<LinkerPatch> patches_;
404 };
405 
406 }  // namespace art
407 
408 #endif  // ART_COMPILER_COMPILED_METHOD_H_
409