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_LIBARTBASE_ARCH_INSTRUCTION_SET_H_
18 #define ART_LIBARTBASE_ARCH_INSTRUCTION_SET_H_
19
20 #include <iosfwd>
21 #include <string>
22
23 #include "base/enums.h"
24 #include "base/macros.h"
25
26 namespace art {
27
28 enum class InstructionSet {
29 kNone,
30 kArm,
31 kArm64,
32 kThumb2,
33 kX86,
34 kX86_64,
35 kMips,
36 kMips64,
37 kLast = kMips64
38 };
39 std::ostream& operator<<(std::ostream& os, const InstructionSet& rhs);
40
41 #if defined(__arm__)
42 static constexpr InstructionSet kRuntimeISA = InstructionSet::kArm;
43 #elif defined(__aarch64__)
44 static constexpr InstructionSet kRuntimeISA = InstructionSet::kArm64;
45 #elif defined(__mips__) && !defined(__LP64__)
46 static constexpr InstructionSet kRuntimeISA = InstructionSet::kMips;
47 #elif defined(__mips__) && defined(__LP64__)
48 static constexpr InstructionSet kRuntimeISA = InstructionSet::kMips64;
49 #elif defined(__i386__)
50 static constexpr InstructionSet kRuntimeISA = InstructionSet::kX86;
51 #elif defined(__x86_64__)
52 static constexpr InstructionSet kRuntimeISA = InstructionSet::kX86_64;
53 #else
54 static constexpr InstructionSet kRuntimeISA = InstructionSet::kNone;
55 #endif
56
57 // Architecture-specific pointer sizes
58 static constexpr PointerSize kArmPointerSize = PointerSize::k32;
59 static constexpr PointerSize kArm64PointerSize = PointerSize::k64;
60 static constexpr PointerSize kMipsPointerSize = PointerSize::k32;
61 static constexpr PointerSize kMips64PointerSize = PointerSize::k64;
62 static constexpr PointerSize kX86PointerSize = PointerSize::k32;
63 static constexpr PointerSize kX86_64PointerSize = PointerSize::k64;
64
65 // ARM instruction alignment. ARM processors require code to be 4-byte aligned,
66 // but ARM ELF requires 8..
67 static constexpr size_t kArmAlignment = 8;
68
69 // ARM64 instruction alignment. This is the recommended alignment for maximum performance.
70 static constexpr size_t kArm64Alignment = 16;
71
72 // MIPS instruction alignment. MIPS processors require code to be 4-byte aligned,
73 // but 64-bit literals must be 8-byte aligned.
74 static constexpr size_t kMipsAlignment = 8;
75
76 // X86 instruction alignment. This is the recommended alignment for maximum performance.
77 static constexpr size_t kX86Alignment = 16;
78
79 // Different than code alignment since code alignment is only first instruction of method.
80 static constexpr size_t kThumb2InstructionAlignment = 2;
81 static constexpr size_t kArm64InstructionAlignment = 4;
82 static constexpr size_t kX86InstructionAlignment = 1;
83 static constexpr size_t kX86_64InstructionAlignment = 1;
84 static constexpr size_t kMipsInstructionAlignment = 4;
85 static constexpr size_t kMips64InstructionAlignment = 4;
86
87 const char* GetInstructionSetString(InstructionSet isa);
88
89 // Note: Returns kNone when the string cannot be parsed to a known value.
90 InstructionSet GetInstructionSetFromString(const char* instruction_set);
91
92 // Fatal logging out of line to keep the header clean of logging.h.
93 NO_RETURN void InstructionSetAbort(InstructionSet isa);
94
GetInstructionSetPointerSize(InstructionSet isa)95 constexpr PointerSize GetInstructionSetPointerSize(InstructionSet isa) {
96 switch (isa) {
97 case InstructionSet::kArm:
98 // Fall-through.
99 case InstructionSet::kThumb2:
100 return kArmPointerSize;
101 case InstructionSet::kArm64:
102 return kArm64PointerSize;
103 case InstructionSet::kX86:
104 return kX86PointerSize;
105 case InstructionSet::kX86_64:
106 return kX86_64PointerSize;
107 case InstructionSet::kMips:
108 return kMipsPointerSize;
109 case InstructionSet::kMips64:
110 return kMips64PointerSize;
111
112 case InstructionSet::kNone:
113 break;
114 }
115 InstructionSetAbort(isa);
116 }
117
GetInstructionSetInstructionAlignment(InstructionSet isa)118 constexpr size_t GetInstructionSetInstructionAlignment(InstructionSet isa) {
119 switch (isa) {
120 case InstructionSet::kArm:
121 // Fall-through.
122 case InstructionSet::kThumb2:
123 return kThumb2InstructionAlignment;
124 case InstructionSet::kArm64:
125 return kArm64InstructionAlignment;
126 case InstructionSet::kX86:
127 return kX86InstructionAlignment;
128 case InstructionSet::kX86_64:
129 return kX86_64InstructionAlignment;
130 case InstructionSet::kMips:
131 return kMipsInstructionAlignment;
132 case InstructionSet::kMips64:
133 return kMips64InstructionAlignment;
134
135 case InstructionSet::kNone:
136 break;
137 }
138 InstructionSetAbort(isa);
139 }
140
IsValidInstructionSet(InstructionSet isa)141 constexpr bool IsValidInstructionSet(InstructionSet isa) {
142 switch (isa) {
143 case InstructionSet::kArm:
144 case InstructionSet::kThumb2:
145 case InstructionSet::kArm64:
146 case InstructionSet::kX86:
147 case InstructionSet::kX86_64:
148 case InstructionSet::kMips:
149 case InstructionSet::kMips64:
150 return true;
151
152 case InstructionSet::kNone:
153 return false;
154 }
155 return false;
156 }
157
158 size_t GetInstructionSetAlignment(InstructionSet isa);
159
Is64BitInstructionSet(InstructionSet isa)160 constexpr bool Is64BitInstructionSet(InstructionSet isa) {
161 switch (isa) {
162 case InstructionSet::kArm:
163 case InstructionSet::kThumb2:
164 case InstructionSet::kX86:
165 case InstructionSet::kMips:
166 return false;
167
168 case InstructionSet::kArm64:
169 case InstructionSet::kX86_64:
170 case InstructionSet::kMips64:
171 return true;
172
173 case InstructionSet::kNone:
174 break;
175 }
176 InstructionSetAbort(isa);
177 }
178
InstructionSetPointerSize(InstructionSet isa)179 constexpr PointerSize InstructionSetPointerSize(InstructionSet isa) {
180 return Is64BitInstructionSet(isa) ? PointerSize::k64 : PointerSize::k32;
181 }
182
GetBytesPerGprSpillLocation(InstructionSet isa)183 constexpr size_t GetBytesPerGprSpillLocation(InstructionSet isa) {
184 switch (isa) {
185 case InstructionSet::kArm:
186 // Fall-through.
187 case InstructionSet::kThumb2:
188 return 4;
189 case InstructionSet::kArm64:
190 return 8;
191 case InstructionSet::kX86:
192 return 4;
193 case InstructionSet::kX86_64:
194 return 8;
195 case InstructionSet::kMips:
196 return 4;
197 case InstructionSet::kMips64:
198 return 8;
199
200 case InstructionSet::kNone:
201 break;
202 }
203 InstructionSetAbort(isa);
204 }
205
GetBytesPerFprSpillLocation(InstructionSet isa)206 constexpr size_t GetBytesPerFprSpillLocation(InstructionSet isa) {
207 switch (isa) {
208 case InstructionSet::kArm:
209 // Fall-through.
210 case InstructionSet::kThumb2:
211 return 4;
212 case InstructionSet::kArm64:
213 return 8;
214 case InstructionSet::kX86:
215 return 8;
216 case InstructionSet::kX86_64:
217 return 8;
218 case InstructionSet::kMips:
219 return 4;
220 case InstructionSet::kMips64:
221 return 8;
222
223 case InstructionSet::kNone:
224 break;
225 }
226 InstructionSetAbort(isa);
227 }
228
229 namespace instruction_set_details {
230
231 #if !defined(ART_STACK_OVERFLOW_GAP_arm) || !defined(ART_STACK_OVERFLOW_GAP_arm64) || \
232 !defined(ART_STACK_OVERFLOW_GAP_mips) || !defined(ART_STACK_OVERFLOW_GAP_mips64) || \
233 !defined(ART_STACK_OVERFLOW_GAP_x86) || !defined(ART_STACK_OVERFLOW_GAP_x86_64)
234 #error "Missing defines for stack overflow gap"
235 #endif
236
237 static constexpr size_t kArmStackOverflowReservedBytes = ART_STACK_OVERFLOW_GAP_arm;
238 static constexpr size_t kArm64StackOverflowReservedBytes = ART_STACK_OVERFLOW_GAP_arm64;
239 static constexpr size_t kMipsStackOverflowReservedBytes = ART_STACK_OVERFLOW_GAP_mips;
240 static constexpr size_t kMips64StackOverflowReservedBytes = ART_STACK_OVERFLOW_GAP_mips64;
241 static constexpr size_t kX86StackOverflowReservedBytes = ART_STACK_OVERFLOW_GAP_x86;
242 static constexpr size_t kX86_64StackOverflowReservedBytes = ART_STACK_OVERFLOW_GAP_x86_64;
243
244 NO_RETURN void GetStackOverflowReservedBytesFailure(const char* error_msg);
245
246 } // namespace instruction_set_details
247
248 ALWAYS_INLINE
GetStackOverflowReservedBytes(InstructionSet isa)249 constexpr size_t GetStackOverflowReservedBytes(InstructionSet isa) {
250 switch (isa) {
251 case InstructionSet::kArm: // Intentional fall-through.
252 case InstructionSet::kThumb2:
253 return instruction_set_details::kArmStackOverflowReservedBytes;
254
255 case InstructionSet::kArm64:
256 return instruction_set_details::kArm64StackOverflowReservedBytes;
257
258 case InstructionSet::kMips:
259 return instruction_set_details::kMipsStackOverflowReservedBytes;
260
261 case InstructionSet::kMips64:
262 return instruction_set_details::kMips64StackOverflowReservedBytes;
263
264 case InstructionSet::kX86:
265 return instruction_set_details::kX86StackOverflowReservedBytes;
266
267 case InstructionSet::kX86_64:
268 return instruction_set_details::kX86_64StackOverflowReservedBytes;
269
270 case InstructionSet::kNone:
271 instruction_set_details::GetStackOverflowReservedBytesFailure(
272 "kNone has no stack overflow size");
273 }
274 instruction_set_details::GetStackOverflowReservedBytesFailure("Unknown instruction set");
275 }
276
277 // The following definitions create return types for two word-sized entities that will be passed
278 // in registers so that memory operations for the interface trampolines can be avoided. The entities
279 // are the resolved method and the pointer to the code to be invoked.
280 //
281 // On x86, ARM32 and MIPS, this is given for a *scalar* 64bit value. The definition thus *must* be
282 // uint64_t or long long int.
283 //
284 // On x86_64, ARM64 and MIPS64, structs are decomposed for allocation, so we can create a structs of
285 // two size_t-sized values.
286 //
287 // We need two operations:
288 //
289 // 1) A flag value that signals failure. The assembly stubs expect the lower part to be "0".
290 // GetTwoWordFailureValue() will return a value that has lower part == 0.
291 //
292 // 2) A value that combines two word-sized values.
293 // GetTwoWordSuccessValue() constructs this.
294 //
295 // IMPORTANT: If you use this to transfer object pointers, it is your responsibility to ensure
296 // that the object does not move or the value is updated. Simple use of this is NOT SAFE
297 // when the garbage collector can move objects concurrently. Ensure that required locks
298 // are held when using!
299
300 #if defined(__i386__) || defined(__arm__) || (defined(__mips__) && !defined(__LP64__))
301 typedef uint64_t TwoWordReturn;
302
303 // Encodes method_ptr==nullptr and code_ptr==nullptr
GetTwoWordFailureValue()304 static inline constexpr TwoWordReturn GetTwoWordFailureValue() {
305 return 0;
306 }
307
308 // Use the lower 32b for the method pointer and the upper 32b for the code pointer.
GetTwoWordSuccessValue(uintptr_t hi,uintptr_t lo)309 static inline constexpr TwoWordReturn GetTwoWordSuccessValue(uintptr_t hi, uintptr_t lo) {
310 static_assert(sizeof(uint32_t) == sizeof(uintptr_t), "Unexpected size difference");
311 uint32_t lo32 = lo;
312 uint64_t hi64 = static_cast<uint64_t>(hi);
313 return ((hi64 << 32) | lo32);
314 }
315
316 #elif defined(__x86_64__) || defined(__aarch64__) || (defined(__mips__) && defined(__LP64__))
317
318 // Note: TwoWordReturn can't be constexpr for 64-bit targets. We'd need a constexpr constructor,
319 // which would violate C-linkage in the entrypoint functions.
320
321 struct TwoWordReturn {
322 uintptr_t lo;
323 uintptr_t hi;
324 };
325
326 // Encodes method_ptr==nullptr. Leaves random value in code pointer.
GetTwoWordFailureValue()327 static inline TwoWordReturn GetTwoWordFailureValue() {
328 TwoWordReturn ret;
329 ret.lo = 0;
330 return ret;
331 }
332
333 // Write values into their respective members.
GetTwoWordSuccessValue(uintptr_t hi,uintptr_t lo)334 static inline TwoWordReturn GetTwoWordSuccessValue(uintptr_t hi, uintptr_t lo) {
335 TwoWordReturn ret;
336 ret.lo = lo;
337 ret.hi = hi;
338 return ret;
339 }
340 #else
341 #error "Unsupported architecture"
342 #endif
343
344 } // namespace art
345
346 #endif // ART_LIBARTBASE_ARCH_INSTRUCTION_SET_H_
347