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_RUNTIME_ARCH_CONTEXT_H_ 18 #define ART_RUNTIME_ARCH_CONTEXT_H_ 19 20 #include <stddef.h> 21 #include <stdint.h> 22 23 #include "arch/instruction_set.h" 24 #include "base/macros.h" 25 #include "entrypoints/quick/runtime_entrypoints_list.h" 26 27 namespace art HIDDEN { 28 29 class QuickMethodFrameInfo; 30 31 // Representation of a thread's context on the executing machine, used to implement long jumps in 32 // the quick stack frame layout. 33 class Context { 34 public: 35 // Creates a context for the running architecture 36 EXPORT static Context* Create(); 37 ~Context()38 virtual ~Context() {} 39 40 // Re-initializes the registers for context re-use. 41 virtual void Reset() = 0; 42 43 template <InstructionSet kIsa> CalleeSaveAddress(uint8_t * frame,int num,size_t frame_size)44 static uintptr_t* CalleeSaveAddress(uint8_t* frame, int num, size_t frame_size) { 45 static constexpr size_t kPointerSize = static_cast<size_t>(GetInstructionSetPointerSize(kIsa)); 46 // Callee saves are held at the top of the frame 47 uint8_t* save_addr = frame + frame_size - ((num + 1) * kPointerSize); 48 if (kIsa == InstructionSet::kX86 || kIsa == InstructionSet::kX86_64) { 49 save_addr -= kPointerSize; // account for return address 50 } 51 return reinterpret_cast<uintptr_t*>(save_addr); 52 } 53 54 // Reads values from callee saves in the given frame. The frame also holds 55 // the method that holds the layout. 56 virtual void FillCalleeSaves(uint8_t* frame, const QuickMethodFrameInfo& fr) = 0; 57 58 // Sets the stack pointer value. 59 virtual void SetSP(uintptr_t new_sp) = 0; 60 61 // Sets the program counter value. 62 virtual void SetPC(uintptr_t new_pc) = 0; 63 64 // Sets the first argument register. 65 virtual void SetArg0(uintptr_t new_arg0_value) = 0; 66 67 // Returns whether the given GPR is accessible (read or write). 68 virtual bool IsAccessibleGPR(uint32_t reg) = 0; 69 70 // Gets the given GPRs address. 71 virtual uintptr_t* GetGPRAddress(uint32_t reg) = 0; 72 73 // Reads the given GPR. The caller is responsible for checking the register 74 // is accessible with IsAccessibleGPR. 75 virtual uintptr_t GetGPR(uint32_t reg) = 0; 76 77 // Sets the given GPR. The caller is responsible for checking the register 78 // is accessible with IsAccessibleGPR. 79 virtual void SetGPR(uint32_t reg, uintptr_t value) = 0; 80 81 // Returns whether the given FPR is accessible (read or write). 82 virtual bool IsAccessibleFPR(uint32_t reg) = 0; 83 84 // Reads the given FPR. The caller is responsible for checking the register 85 // is accessible with IsAccessibleFPR. 86 virtual uintptr_t GetFPR(uint32_t reg) = 0; 87 88 // Sets the given FPR. The caller is responsible for checking the register 89 // is accessible with IsAccessibleFPR. 90 virtual void SetFPR(uint32_t reg, uintptr_t value) = 0; 91 92 // Smashes the caller save registers. If we're throwing, we don't want to return bogus values. 93 virtual void SmashCallerSaves() = 0; 94 95 // Set `new_value` to the physical register containing the dex PC pointer in 96 // an nterp frame. SetNterpDexPC(uintptr_t new_value)97 virtual void SetNterpDexPC([[maybe_unused]] uintptr_t new_value) { abort(); } 98 99 // Copies the values of GPRs and FPRs registers from this context to external buffers; 100 // the use case is to do a long jump afterwards. 101 virtual void CopyContextTo(uintptr_t* gprs, uintptr_t* fprs) = 0; 102 103 enum { 104 kBadGprBase = 0xebad6070, 105 kBadFprBase = 0xebad8070, 106 }; 107 }; 108 109 } // namespace art 110 111 #endif // ART_RUNTIME_ARCH_CONTEXT_H_ 112