1 /*
2  * Copyright (C) 2014 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_ARM64_CONTEXT_ARM64_H_
18 #define ART_RUNTIME_ARCH_ARM64_CONTEXT_ARM64_H_
19 
20 #include "arch/context.h"
21 #include "base/logging.h"
22 #include "base/macros.h"
23 #include "registers_arm64.h"
24 
25 namespace art {
26 namespace arm64 {
27 
28 class Arm64Context : public Context {
29  public:
Arm64Context()30   Arm64Context() {
31     Reset();
32   }
33 
~Arm64Context()34   ~Arm64Context() {}
35 
36   void Reset() OVERRIDE;
37 
38   void FillCalleeSaves(uint8_t* frame, const QuickMethodFrameInfo& fr) OVERRIDE;
39 
SetSP(uintptr_t new_sp)40   void SetSP(uintptr_t new_sp) OVERRIDE {
41     SetGPR(SP, new_sp);
42   }
43 
SetPC(uintptr_t new_lr)44   void SetPC(uintptr_t new_lr) OVERRIDE {
45     SetGPR(kPC, new_lr);
46   }
47 
SetArg0(uintptr_t new_arg0_value)48   void SetArg0(uintptr_t new_arg0_value) OVERRIDE {
49     SetGPR(X0, new_arg0_value);
50   }
51 
IsAccessibleGPR(uint32_t reg)52   bool IsAccessibleGPR(uint32_t reg) OVERRIDE {
53     DCHECK_LT(reg, arraysize(gprs_));
54     return gprs_[reg] != nullptr;
55   }
56 
GetGPRAddress(uint32_t reg)57   uintptr_t* GetGPRAddress(uint32_t reg) OVERRIDE {
58     DCHECK_LT(reg, arraysize(gprs_));
59     return gprs_[reg];
60   }
61 
GetGPR(uint32_t reg)62   uintptr_t GetGPR(uint32_t reg) OVERRIDE {
63     // Note: PC isn't an available GPR (outside of internals), so don't allow retrieving the value.
64     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfXRegisters));
65     DCHECK(IsAccessibleGPR(reg));
66     return *gprs_[reg];
67   }
68 
69   void SetGPR(uint32_t reg, uintptr_t value) OVERRIDE;
70 
IsAccessibleFPR(uint32_t reg)71   bool IsAccessibleFPR(uint32_t reg) OVERRIDE {
72     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfDRegisters));
73     return fprs_[reg] != nullptr;
74   }
75 
GetFPR(uint32_t reg)76   uintptr_t GetFPR(uint32_t reg) OVERRIDE {
77     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfDRegisters));
78     DCHECK(IsAccessibleFPR(reg));
79     return *fprs_[reg];
80   }
81 
82   void SetFPR(uint32_t reg, uintptr_t value) OVERRIDE;
83 
84   void SmashCallerSaves() OVERRIDE;
85   NO_RETURN void DoLongJump() OVERRIDE;
86 
87   static constexpr size_t kPC = kNumberOfXRegisters;
88 
89  private:
90   // Pointers to register locations, initialized to null or the specific registers below. We need
91   // an additional one for the PC.
92   uintptr_t* gprs_[kNumberOfXRegisters + 1];
93   uint64_t * fprs_[kNumberOfDRegisters];
94   // Hold values for sp, pc and arg0 if they are not located within a stack frame.
95   uintptr_t sp_, pc_, arg0_;
96 };
97 
98 }  // namespace arm64
99 }  // namespace art
100 
101 #endif  // ART_RUNTIME_ARCH_ARM64_CONTEXT_ARM64_H_
102