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_X86_CONTEXT_X86_H_
18 #define ART_RUNTIME_ARCH_X86_CONTEXT_X86_H_
19 
20 #include "arch/context.h"
21 #include "base/logging.h"
22 #include "registers_x86.h"
23 
24 namespace art {
25 namespace x86 {
26 
27 class X86Context : public Context {
28  public:
X86Context()29   X86Context() {
30     Reset();
31   }
~X86Context()32   virtual ~X86Context() {}
33 
34   void Reset() OVERRIDE;
35 
36   void FillCalleeSaves(const StackVisitor& fr) OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
37 
SetSP(uintptr_t new_sp)38   void SetSP(uintptr_t new_sp) OVERRIDE {
39     bool success = SetGPR(ESP, new_sp);
40     CHECK(success) << "Failed to set ESP register";
41   }
42 
SetPC(uintptr_t new_pc)43   void SetPC(uintptr_t new_pc) OVERRIDE {
44     eip_ = new_pc;
45   }
46 
GetGPRAddress(uint32_t reg)47   uintptr_t* GetGPRAddress(uint32_t reg) OVERRIDE {
48     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfCpuRegisters));
49     return gprs_[reg];
50   }
51 
GetGPR(uint32_t reg,uintptr_t * val)52   bool GetGPR(uint32_t reg, uintptr_t* val) OVERRIDE {
53     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfCpuRegisters));
54     if (gprs_[reg] == nullptr) {
55       return false;
56     } else {
57       DCHECK(val != nullptr);
58       *val = *gprs_[reg];
59       return true;
60     }
61   }
62 
63   bool SetGPR(uint32_t reg, uintptr_t value) OVERRIDE;
64 
GetFPR(uint32_t reg,uintptr_t * val)65   bool GetFPR(uint32_t reg, uintptr_t* val) OVERRIDE {
66     LOG(FATAL) << "Floating-point registers are all caller save in X86";
67     return false;
68   }
69 
SetFPR(uint32_t reg,uintptr_t value)70   bool SetFPR(uint32_t reg, uintptr_t value) OVERRIDE {
71     LOG(FATAL) << "Floating-point registers are all caller save in X86";
72     return false;
73   }
74 
75   void SmashCallerSaves() OVERRIDE;
76   void DoLongJump() OVERRIDE;
77 
78  private:
79   // Pointers to register locations, floating point registers are all caller save. Values are
80   // initialized to NULL or the special registers below.
81   uintptr_t* gprs_[kNumberOfCpuRegisters];
82   // Hold values for esp and eip if they are not located within a stack frame. EIP is somewhat
83   // special in that it cannot be encoded normally as a register operand to an instruction (except
84   // in 64bit addressing modes).
85   uintptr_t esp_, eip_;
86 };
87 }  // namespace x86
88 }  // namespace art
89 
90 #endif  // ART_RUNTIME_ARCH_X86_CONTEXT_X86_H_
91