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 "base/macros.h"
23 #include "registers_x86.h"
24 
25 namespace art {
26 namespace x86 {
27 
28 class X86Context : public Context {
29  public:
X86Context()30   X86Context() {
31     Reset();
32   }
~X86Context()33   virtual ~X86Context() {}
34 
35   void Reset() OVERRIDE;
36 
37   void FillCalleeSaves(const StackVisitor& fr) OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
38 
SetSP(uintptr_t new_sp)39   void SetSP(uintptr_t new_sp) OVERRIDE {
40     SetGPR(ESP, new_sp);
41   }
42 
SetPC(uintptr_t new_pc)43   void SetPC(uintptr_t new_pc) OVERRIDE {
44     eip_ = new_pc;
45   }
46 
IsAccessibleGPR(uint32_t reg)47   bool IsAccessibleGPR(uint32_t reg) OVERRIDE {
48     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfCpuRegisters));
49     return gprs_[reg] != nullptr;
50   }
51 
GetGPRAddress(uint32_t reg)52   uintptr_t* GetGPRAddress(uint32_t reg) OVERRIDE {
53     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfCpuRegisters));
54     return gprs_[reg];
55   }
56 
GetGPR(uint32_t reg)57   uintptr_t GetGPR(uint32_t reg) OVERRIDE {
58     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfCpuRegisters));
59     DCHECK(IsAccessibleGPR(reg));
60     return *gprs_[reg];
61   }
62 
63   void SetGPR(uint32_t reg, uintptr_t value) OVERRIDE;
64 
IsAccessibleFPR(uint32_t reg)65   bool IsAccessibleFPR(uint32_t reg) OVERRIDE {
66     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfFloatRegisters));
67     return fprs_[reg] != nullptr;
68   }
69 
GetFPR(uint32_t reg)70   uintptr_t GetFPR(uint32_t reg) OVERRIDE {
71     DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfFloatRegisters));
72     DCHECK(IsAccessibleFPR(reg));
73     return *fprs_[reg];
74   }
75 
76   void SetFPR(uint32_t reg, uintptr_t value) OVERRIDE;
77 
78   void SmashCallerSaves() OVERRIDE;
79   NO_RETURN void DoLongJump() OVERRIDE;
80 
81  private:
82   // Pretend XMM registers are made of uin32_t pieces, because they are manipulated
83   // in uint32_t chunks.
84   enum {
85     XMM0_0 = 0, XMM0_1,
86     XMM1_0, XMM1_1,
87     XMM2_0, XMM2_1,
88     XMM3_0, XMM3_1,
89     XMM4_0, XMM4_1,
90     XMM5_0, XMM5_1,
91     XMM6_0, XMM6_1,
92     XMM7_0, XMM7_1,
93     kNumberOfFloatRegisters};
94 
95   // Pointers to register locations. Values are initialized to null or the special registers below.
96   uintptr_t* gprs_[kNumberOfCpuRegisters];
97   uint32_t* fprs_[kNumberOfFloatRegisters];
98   // Hold values for esp and eip if they are not located within a stack frame. EIP is somewhat
99   // special in that it cannot be encoded normally as a register operand to an instruction (except
100   // in 64bit addressing modes).
101   uintptr_t esp_, eip_;
102 };
103 }  // namespace x86
104 }  // namespace art
105 
106 #endif  // ART_RUNTIME_ARCH_X86_CONTEXT_X86_H_
107