Home | History | Annotate | Download | only in linker 
      1 /*
      2  * Copyright (C) 2015 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 #include "linker/relative_patcher.h"
     18 
     19 #ifdef ART_ENABLE_CODEGEN_arm
     20 #include "linker/arm/relative_patcher_thumb2.h"
     21 #endif
     22 #ifdef ART_ENABLE_CODEGEN_arm64
     23 #include "linker/arm64/relative_patcher_arm64.h"
     24 #endif
     25 #ifdef ART_ENABLE_CODEGEN_x86
     26 #include "linker/x86/relative_patcher_x86.h"
     27 #endif
     28 #ifdef ART_ENABLE_CODEGEN_x86_64
     29 #include "linker/x86_64/relative_patcher_x86_64.h"
     30 #endif
     31 #include "output_stream.h"
     32 
     33 namespace art {
     34 namespace linker {
     35 
     36 std::unique_ptr<RelativePatcher> RelativePatcher::Create(
     37     InstructionSet instruction_set,
     38     const InstructionSetFeatures* features,
     39     RelativePatcherTargetProvider* provider) {
     40   class RelativePatcherNone FINAL : public RelativePatcher {
     41    public:
     42     RelativePatcherNone() { }
     43 
     44     uint32_t ReserveSpace(uint32_t offset,
     45                           const CompiledMethod* compiled_method ATTRIBUTE_UNUSED,
     46                           MethodReference method_ref ATTRIBUTE_UNUSED) OVERRIDE {
     47       return offset;  // No space reserved; no patches expected.
     48     }
     49 
     50     uint32_t ReserveSpaceEnd(uint32_t offset) OVERRIDE {
     51       return offset;  // No space reserved; no patches expected.
     52     }
     53 
     54     uint32_t WriteThunks(OutputStream* out ATTRIBUTE_UNUSED, uint32_t offset) OVERRIDE {
     55       return offset;  // No thunks added; no patches expected.
     56     }
     57 
     58     void PatchCall(std::vector<uint8_t>* code ATTRIBUTE_UNUSED,
     59                    uint32_t literal_offset ATTRIBUTE_UNUSED,
     60                    uint32_t patch_offset ATTRIBUTE_UNUSED,
     61                    uint32_t target_offset ATTRIBUTE_UNUSED) OVERRIDE {
     62       LOG(FATAL) << "Unexpected relative call patch.";
     63     }
     64 
     65     void PatchPcRelativeReference(std::vector<uint8_t>* code ATTRIBUTE_UNUSED,
     66                                   const LinkerPatch& patch ATTRIBUTE_UNUSED,
     67                                   uint32_t patch_offset ATTRIBUTE_UNUSED,
     68                                   uint32_t target_offset ATTRIBUTE_UNUSED) OVERRIDE {
     69       LOG(FATAL) << "Unexpected relative dex cache array patch.";
     70     }
     71 
     72    private:
     73     DISALLOW_COPY_AND_ASSIGN(RelativePatcherNone);
     74   };
     75 
     76   UNUSED(features);
     77   UNUSED(provider);
     78   switch (instruction_set) {
     79 #ifdef ART_ENABLE_CODEGEN_x86
     80     case kX86:
     81       return std::unique_ptr<RelativePatcher>(new X86RelativePatcher());
     82 #endif
     83 #ifdef ART_ENABLE_CODEGEN_x86_64
     84     case kX86_64:
     85       return std::unique_ptr<RelativePatcher>(new X86_64RelativePatcher());
     86 #endif
     87 #ifdef ART_ENABLE_CODEGEN_arm
     88     case kArm:
     89       // Fall through: we generate Thumb2 code for "arm".
     90     case kThumb2:
     91       return std::unique_ptr<RelativePatcher>(new Thumb2RelativePatcher(provider));
     92 #endif
     93 #ifdef ART_ENABLE_CODEGEN_arm64
     94     case kArm64:
     95       return std::unique_ptr<RelativePatcher>(
     96           new Arm64RelativePatcher(provider, features->AsArm64InstructionSetFeatures()));
     97 #endif
     98     default:
     99       return std::unique_ptr<RelativePatcher>(new RelativePatcherNone);
    100   }
    101 }
    102 
    103 bool RelativePatcher::WriteCodeAlignment(OutputStream* out, uint32_t aligned_code_delta) {
    104   static const uint8_t kPadding[] = {
    105       0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u
    106   };
    107   DCHECK_LE(aligned_code_delta, sizeof(kPadding));
    108   if (UNLIKELY(!out->WriteFully(kPadding, aligned_code_delta))) {
    109     return false;
    110   }
    111   size_code_alignment_ += aligned_code_delta;
    112   return true;
    113 }
    114 
    115 bool RelativePatcher::WriteRelCallThunk(OutputStream* out, const ArrayRef<const uint8_t>& thunk) {
    116   if (UNLIKELY(!out->WriteFully(thunk.data(), thunk.size()))) {
    117     return false;
    118   }
    119   size_relative_call_thunks_ += thunk.size();
    120   return true;
    121 }
    122 
    123 bool RelativePatcher::WriteMiscThunk(OutputStream* out, const ArrayRef<const uint8_t>& thunk) {
    124   if (UNLIKELY(!out->WriteFully(thunk.data(), thunk.size()))) {
    125     return false;
    126   }
    127   size_misc_thunks_ += thunk.size();
    128   return true;
    129 }
    130 
    131 }  // namespace linker
    132 }  // namespace art
    133