1 // Copyright 2012 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_ARM_FRAMES_ARM_H_ 6 #define V8_ARM_FRAMES_ARM_H_ 7 8 namespace v8 { 9 namespace internal { 10 11 12 // The ARM ABI does not specify the usage of register r9, which may be reserved 13 // as the static base or thread register on some platforms, in which case we 14 // leave it alone. Adjust the value of kR9Available accordingly: 15 const int kR9Available = 1; // 1 if available to us, 0 if reserved 16 17 18 // Register list in load/store instructions 19 // Note that the bit values must match those used in actual instruction encoding 20 const int kNumRegs = 16; 21 22 23 // Caller-saved/arguments registers 24 const RegList kJSCallerSaved = 25 1 << 0 | // r0 a1 26 1 << 1 | // r1 a2 27 1 << 2 | // r2 a3 28 1 << 3; // r3 a4 29 30 const int kNumJSCallerSaved = 4; 31 32 // Return the code of the n-th caller-saved register available to JavaScript 33 // e.g. JSCallerSavedReg(0) returns r0.code() == 0 34 int JSCallerSavedCode(int n); 35 36 37 // Callee-saved registers preserved when switching from C to JavaScript 38 const RegList kCalleeSaved = 39 1 << 4 | // r4 v1 40 1 << 5 | // r5 v2 41 1 << 6 | // r6 v3 42 1 << 7 | // r7 v4 (cp in JavaScript code) 43 1 << 8 | // r8 v5 (pp in JavaScript code) 44 kR9Available << 9 | // r9 v6 45 1 << 10 | // r10 v7 46 1 << 11; // r11 v8 (fp in JavaScript code) 47 48 // When calling into C++ (only for C++ calls that can't cause a GC). 49 // The call code will take care of lr, fp, etc. 50 const RegList kCallerSaved = 51 1 << 0 | // r0 52 1 << 1 | // r1 53 1 << 2 | // r2 54 1 << 3 | // r3 55 1 << 9; // r9 56 57 58 const int kNumCalleeSaved = 7 + kR9Available; 59 60 // Double registers d8 to d15 are callee-saved. 61 const int kNumDoubleCalleeSaved = 8; 62 63 64 // Number of registers for which space is reserved in safepoints. Must be a 65 // multiple of 8. 66 // TODO(regis): Only 8 registers may actually be sufficient. Revisit. 67 const int kNumSafepointRegisters = 16; 68 69 // Define the list of registers actually saved at safepoints. 70 // Note that the number of saved registers may be smaller than the reserved 71 // space, i.e. kNumSafepointSavedRegisters <= kNumSafepointRegisters. 72 const RegList kSafepointSavedRegisters = kJSCallerSaved | kCalleeSaved; 73 const int kNumSafepointSavedRegisters = kNumJSCallerSaved + kNumCalleeSaved; 74 75 // ---------------------------------------------------- 76 77 78 class EntryFrameConstants : public AllStatic { 79 public: 80 static const int kCallerFPOffset = 81 -(StandardFrameConstants::kFixedFrameSizeFromFp + kPointerSize); 82 }; 83 84 85 class ExitFrameConstants : public AllStatic { 86 public: 87 static const int kFrameSize = FLAG_enable_ool_constant_pool ? 88 3 * kPointerSize : 2 * kPointerSize; 89 90 static const int kConstantPoolOffset = FLAG_enable_ool_constant_pool ? 91 -3 * kPointerSize : 0; 92 static const int kCodeOffset = -2 * kPointerSize; 93 static const int kSPOffset = -1 * kPointerSize; 94 95 // The caller fields are below the frame pointer on the stack. 96 static const int kCallerFPOffset = 0 * kPointerSize; 97 // The calling JS function is below FP. 98 static const int kCallerPCOffset = 1 * kPointerSize; 99 100 // FP-relative displacement of the caller's SP. It points just 101 // below the saved PC. 102 static const int kCallerSPDisplacement = 2 * kPointerSize; 103 }; 104 105 106 class JavaScriptFrameConstants : public AllStatic { 107 public: 108 // FP-relative. 109 static const int kLocal0Offset = StandardFrameConstants::kExpressionsOffset; 110 static const int kLastParameterOffset = +2 * kPointerSize; 111 static const int kFunctionOffset = StandardFrameConstants::kMarkerOffset; 112 113 // Caller SP-relative. 114 static const int kParam0Offset = -2 * kPointerSize; 115 static const int kReceiverOffset = -1 * kPointerSize; 116 }; 117 118 119 class ArgumentsAdaptorFrameConstants : public AllStatic { 120 public: 121 // FP-relative. 122 static const int kLengthOffset = StandardFrameConstants::kExpressionsOffset; 123 124 static const int kFrameSize = 125 StandardFrameConstants::kFixedFrameSize + kPointerSize; 126 }; 127 128 129 class ConstructFrameConstants : public AllStatic { 130 public: 131 // FP-relative. 132 static const int kImplicitReceiverOffset = -6 * kPointerSize; 133 static const int kConstructorOffset = -5 * kPointerSize; 134 static const int kLengthOffset = -4 * kPointerSize; 135 static const int kCodeOffset = StandardFrameConstants::kExpressionsOffset; 136 137 static const int kFrameSize = 138 StandardFrameConstants::kFixedFrameSize + 4 * kPointerSize; 139 }; 140 141 142 class InternalFrameConstants : public AllStatic { 143 public: 144 // FP-relative. 145 static const int kCodeOffset = StandardFrameConstants::kExpressionsOffset; 146 }; 147 148 149 inline Object* JavaScriptFrame::function_slot_object() const { 150 const int offset = JavaScriptFrameConstants::kFunctionOffset; 151 return Memory::Object_at(fp() + offset); 152 } 153 154 155 inline void StackHandler::SetFp(Address slot, Address fp) { 156 Memory::Address_at(slot) = fp; 157 } 158 159 160 } } // namespace v8::internal 161 162 #endif // V8_ARM_FRAMES_ARM_H_ 163
