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_COMPILER_UTILS_ARM64_ASSEMBLER_ARM64_H_
18 #define ART_COMPILER_UTILS_ARM64_ASSEMBLER_ARM64_H_
19 
20 #include <stdint.h>
21 #include <memory>
22 #include <vector>
23 
24 #include <android-base/logging.h>
25 
26 #include "base/bit_utils_iterator.h"
27 #include "base/macros.h"
28 #include "dwarf/register.h"
29 #include "offsets.h"
30 #include "utils/arm64/managed_register_arm64.h"
31 #include "utils/assembler.h"
32 
33 // TODO(VIXL): Make VIXL compile with -Wshadow.
34 #pragma GCC diagnostic push
35 #pragma GCC diagnostic ignored "-Wshadow"
36 #include "aarch64/disasm-aarch64.h"
37 #include "aarch64/macro-assembler-aarch64.h"
38 #pragma GCC diagnostic pop
39 
40 namespace art HIDDEN {
41 
42 class Arm64InstructionSetFeatures;
43 
44 namespace arm64 {
45 
DWARFReg(vixl::aarch64::CPURegister reg)46 static inline dwarf::Reg DWARFReg(vixl::aarch64::CPURegister reg) {
47   if (reg.IsFPRegister()) {
48     return dwarf::Reg::Arm64Fp(reg.GetCode());
49   } else {
50     DCHECK_LT(reg.GetCode(), 31u);  // X0 - X30.
51     return dwarf::Reg::Arm64Core(reg.GetCode());
52   }
53 }
54 
55 #define MEM_OP(...)      vixl::aarch64::MemOperand(__VA_ARGS__)
56 
57 enum LoadOperandType {
58   kLoadSignedByte,
59   kLoadUnsignedByte,
60   kLoadSignedHalfword,
61   kLoadUnsignedHalfword,
62   kLoadWord,
63   kLoadCoreWord,
64   kLoadSWord,
65   kLoadDWord
66 };
67 
68 enum StoreOperandType {
69   kStoreByte,
70   kStoreHalfword,
71   kStoreWord,
72   kStoreCoreWord,
73   kStoreSWord,
74   kStoreDWord
75 };
76 
77 class Arm64Assembler final : public Assembler {
78  public:
79   explicit Arm64Assembler(
80       ArenaAllocator* allocator, const Arm64InstructionSetFeatures* features = nullptr);
81 
~Arm64Assembler()82   virtual ~Arm64Assembler() {}
83 
GetVIXLAssembler()84   vixl::aarch64::MacroAssembler* GetVIXLAssembler() { return &vixl_masm_; }
85 
86   // Finalize the code.
87   void FinalizeCode() override;
88 
89   // Size of generated code.
90   size_t CodeSize() const override;
91   const uint8_t* CodeBufferBaseAddress() const override;
92 
93   // Copy instructions out of assembly buffer into the given region of memory.
94   void CopyInstructions(const MemoryRegion& region) override;
95 
96   void LoadRawPtr(ManagedRegister dest, ManagedRegister base, Offset offs);
97 
98   void SpillRegisters(vixl::aarch64::CPURegList registers, int offset);
99   void UnspillRegisters(vixl::aarch64::CPURegList registers, int offset);
100 
101   // A helper to save/restore a list of ZRegisters to a specified stack offset location.
102   template <bool is_save>
SaveRestoreZRegisterList(uint32_t vreg_bit_vector,int64_t stack_offset)103   void SaveRestoreZRegisterList(uint32_t vreg_bit_vector, int64_t stack_offset) {
104     if (vreg_bit_vector == 0) {
105       return;
106     }
107     vixl::aarch64::UseScratchRegisterScope temps(GetVIXLAssembler());
108     vixl::aarch64::Register temp = temps.AcquireX();
109     vixl_masm_.Add(temp, vixl::aarch64::sp, stack_offset);
110     size_t slot_no = 0;
111     for (uint32_t i : LowToHighBits(vreg_bit_vector)) {
112       if (is_save) {
113         vixl_masm_.Str(vixl::aarch64::ZRegister(i),
114                        vixl::aarch64::SVEMemOperand(temp, slot_no, vixl::aarch64::SVE_MUL_VL));
115       } else {
116         vixl_masm_.Ldr(vixl::aarch64::ZRegister(i),
117                        vixl::aarch64::SVEMemOperand(temp, slot_no, vixl::aarch64::SVE_MUL_VL));
118       }
119       slot_no++;
120     }
121   }
122 
123   // Jump to address (not setting link register)
124   void JumpTo(ManagedRegister m_base, Offset offs, ManagedRegister m_scratch);
125 
126   //
127   // Heap poisoning.
128   //
129 
130   // Poison a heap reference contained in `reg`.
131   void PoisonHeapReference(vixl::aarch64::Register reg);
132   // Unpoison a heap reference contained in `reg`.
133   void UnpoisonHeapReference(vixl::aarch64::Register reg);
134   // Poison a heap reference contained in `reg` if heap poisoning is enabled.
135   void MaybePoisonHeapReference(vixl::aarch64::Register reg);
136   // Unpoison a heap reference contained in `reg` if heap poisoning is enabled.
137   void MaybeUnpoisonHeapReference(vixl::aarch64::Register reg);
138 
139   // Emit code checking the status of the Marking Register, and aborting
140   // the program if MR does not match the value stored in the art::Thread
141   // object.
142   //
143   // Argument `temp` is used as a temporary register to generate code.
144   // Argument `code` is used to identify the different occurrences of
145   // MaybeGenerateMarkingRegisterCheck and is passed to the BRK instruction.
146   void GenerateMarkingRegisterCheck(vixl::aarch64::Register temp, int code = 0);
147 
Bind(Label * label)148   void Bind([[maybe_unused]] Label* label) override {
149     UNIMPLEMENTED(FATAL) << "Do not use Bind(Label*) for ARM64";
150   }
Jump(Label * label)151   void Jump([[maybe_unused]] Label* label) override {
152     UNIMPLEMENTED(FATAL) << "Do not use Jump(Label*) for ARM64";
153   }
154 
Bind(vixl::aarch64::Label * label)155   void Bind(vixl::aarch64::Label* label) {
156     vixl_masm_.Bind(label);
157   }
Jump(vixl::aarch64::Label * label)158   void Jump(vixl::aarch64::Label* label) {
159     vixl_masm_.B(label);
160   }
161 
reg_x(int code)162   static vixl::aarch64::Register reg_x(int code) {
163     CHECK(code < kNumberOfXRegisters) << code;
164     if (code == SP) {
165       return vixl::aarch64::sp;
166     } else if (code == XZR) {
167       return vixl::aarch64::xzr;
168     }
169     return vixl::aarch64::XRegister(code);
170   }
171 
reg_w(int code)172   static vixl::aarch64::Register reg_w(int code) {
173     CHECK(code < kNumberOfWRegisters) << code;
174     if (code == WSP) {
175       return vixl::aarch64::wsp;
176     } else if (code == WZR) {
177       return vixl::aarch64::wzr;
178     }
179     return vixl::aarch64::WRegister(code);
180   }
181 
reg_d(int code)182   static vixl::aarch64::VRegister reg_d(int code) {
183     return vixl::aarch64::DRegister(code);
184   }
185 
reg_s(int code)186   static vixl::aarch64::VRegister reg_s(int code) {
187     return vixl::aarch64::SRegister(code);
188   }
189 
190  private:
191   // VIXL assembler.
192   vixl::aarch64::MacroAssembler vixl_masm_;
193 
194   // Used for testing.
195   friend class Arm64ManagedRegister_VixlRegisters_Test;
196 };
197 
198 }  // namespace arm64
199 }  // namespace art
200 
201 #endif  // ART_COMPILER_UTILS_ARM64_ASSEMBLER_ARM64_H_
202