xref: /freebsd/contrib/llvm-project/compiler-rt/lib/profile/InstrProfiling.h (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
1 /*===- InstrProfiling.h- Support library for PGO instrumentation ----------===*\
2 |*
3 |* Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 |* See https://llvm.org/LICENSE.txt for license information.
5 |* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 |*
7 \*===----------------------------------------------------------------------===*/
8 
9 #ifndef PROFILE_INSTRPROFILING_H_
10 #define PROFILE_INSTRPROFILING_H_
11 
12 #include "InstrProfilingPort.h"
13 #include <stdio.h>
14 
15 // Make sure __LLVM_INSTR_PROFILE_GENERATE is always defined before
16 // including instr_prof_interface.h so the interface functions are
17 // declared correctly for the runtime.
18 // __LLVM_INSTR_PROFILE_GENERATE is always `#undef`ed after the header,
19 // because compiler-rt does not support profiling the profiling runtime itself.
20 #ifndef __LLVM_INSTR_PROFILE_GENERATE
21 #define __LLVM_INSTR_PROFILE_GENERATE
22 #endif
23 #include "profile/instr_prof_interface.h"
24 #undef __LLVM_INSTR_PROFILE_GENERATE
25 
26 #define INSTR_PROF_VISIBILITY COMPILER_RT_VISIBILITY
27 #include "profile/InstrProfData.inc"
28 
29 enum ValueKind {
30 #define VALUE_PROF_KIND(Enumerator, Value, Descr) Enumerator = Value,
31 #include "profile/InstrProfData.inc"
32 };
33 
34 typedef void *IntPtrT;
35 typedef struct COMPILER_RT_ALIGNAS(INSTR_PROF_DATA_ALIGNMENT)
36     __llvm_profile_data {
37 #define INSTR_PROF_DATA(Type, LLVMType, Name, Initializer) Type Name;
38 #include "profile/InstrProfData.inc"
39 } __llvm_profile_data;
40 
41 typedef struct __llvm_profile_header {
42 #define INSTR_PROF_RAW_HEADER(Type, Name, Initializer) Type Name;
43 #include "profile/InstrProfData.inc"
44 } __llvm_profile_header;
45 
46 typedef struct ValueProfNode * PtrToNodeT;
47 typedef struct ValueProfNode {
48 #define INSTR_PROF_VALUE_NODE(Type, LLVMType, Name, Initializer) Type Name;
49 #include "profile/InstrProfData.inc"
50 } ValueProfNode;
51 
52 typedef struct COMPILER_RT_ALIGNAS(INSTR_PROF_DATA_ALIGNMENT) VTableProfData {
53 #define INSTR_PROF_VTABLE_DATA(Type, LLVMType, Name, Initializer) Type Name;
54 #include "profile/InstrProfData.inc"
55 } VTableProfData;
56 
57 /*!
58  * \brief Return 1 if profile counters are continuously synced to the raw
59  * profile via an mmap(). This is in contrast to the default mode, in which
60  * the raw profile is written out at program exit time.
61  */
62 int __llvm_profile_is_continuous_mode_enabled(void);
63 
64 /*!
65  * \brief Enable continuous mode.
66  *
67  * See \ref __llvm_profile_is_continuous_mode_enabled. The behavior is undefined
68  * if continuous mode is already enabled, or if it cannot be enable due to
69  * conflicting options.
70  */
71 void __llvm_profile_enable_continuous_mode(void);
72 
73 /*!
74  * \brief Disable continuous mode.
75  *
76  */
77 void __llvm_profile_disable_continuous_mode(void);
78 
79 /*!
80  * \brief Set the page size.
81  *
82  * This is a pre-requisite for enabling continuous mode. The buffer size
83  * calculation code inside of libprofile cannot simply call getpagesize(), as
84  * it is not allowed to depend on libc.
85  */
86 void __llvm_profile_set_page_size(unsigned PageSize);
87 
88 /*!
89  * \brief Get number of bytes necessary to pad the argument to eight
90  * byte boundary.
91  */
92 uint8_t __llvm_profile_get_num_padding_bytes(uint64_t SizeInBytes);
93 
94 /*!
95  * \brief Get required size for profile buffer.
96  */
97 uint64_t __llvm_profile_get_size_for_buffer(void);
98 
99 /*!
100  * \brief Write instrumentation data to the given buffer.
101  *
102  * \pre \c Buffer is the start of a buffer at least as big as \a
103  * __llvm_profile_get_size_for_buffer().
104  */
105 int __llvm_profile_write_buffer(char *Buffer);
106 
107 const __llvm_profile_data *__llvm_profile_begin_data(void);
108 const __llvm_profile_data *__llvm_profile_end_data(void);
109 const char *__llvm_profile_begin_names(void);
110 const char *__llvm_profile_end_names(void);
111 const char *__llvm_profile_begin_vtabnames(void);
112 const char *__llvm_profile_end_vtabnames(void);
113 char *__llvm_profile_begin_counters(void);
114 char *__llvm_profile_end_counters(void);
115 char *__llvm_profile_begin_bitmap(void);
116 char *__llvm_profile_end_bitmap(void);
117 ValueProfNode *__llvm_profile_begin_vnodes();
118 ValueProfNode *__llvm_profile_end_vnodes();
119 const VTableProfData *__llvm_profile_begin_vtables();
120 const VTableProfData *__llvm_profile_end_vtables();
121 uint32_t *__llvm_profile_begin_orderfile();
122 
123 /*!
124  * \brief Merge profile data from buffer.
125  *
126  * Read profile data from buffer \p Profile and merge with in-process profile
127  * counters and bitmaps. The client is expected to have checked or already
128  * know the profile data in the buffer matches the in-process counter
129  * structure before calling it. Returns 0 (success) if the profile data is
130  * valid. Upon reading invalid/corrupted profile data, returns 1 (failure).
131  */
132 int __llvm_profile_merge_from_buffer(const char *Profile, uint64_t Size);
133 
134 /*! \brief Check if profile in buffer matches the current binary.
135  *
136  *  Returns 0 (success) if the profile data in buffer \p Profile with size
137  *  \p Size was generated by the same binary and therefore matches
138  *  structurally the in-process counters and bitmaps. If the profile data in
139  *  buffer is not compatible, the interface returns 1 (failure).
140  */
141 int __llvm_profile_check_compatibility(const char *Profile,
142                                        uint64_t Size);
143 
144 /*!
145  * \brief Counts the number of times a target value is seen.
146  *
147  * Records the target value for the CounterIndex if not seen before. Otherwise,
148  * increments the counter associated w/ the target value.
149  * void __llvm_profile_instrument_target(uint64_t TargetValue, void *Data,
150  *                                       uint32_t CounterIndex);
151  */
152 void INSTR_PROF_VALUE_PROF_FUNC(
153 #define VALUE_PROF_FUNC_PARAM(ArgType, ArgName, ArgLLVMType) ArgType ArgName
154 #include "profile/InstrProfData.inc"
155     );
156 
157 void __llvm_profile_instrument_target_value(uint64_t TargetValue, void *Data,
158                                             uint32_t CounterIndex,
159                                             uint64_t CounterValue);
160 
161 /*!
162  * \brief Write instrumentation data to the current file.
163  *
164  * Writes to the file with the last name given to \a *
165  * __llvm_profile_set_filename(),
166  * or if it hasn't been called, the \c LLVM_PROFILE_FILE environment variable,
167  * or if that's not set, the last name set to INSTR_PROF_PROFILE_NAME_VAR,
168  * or if that's not set,  \c "default.profraw".
169  */
170 int __llvm_profile_write_file(void);
171 
172 int __llvm_orderfile_write_file(void);
173 
174 /*!
175  * \brief Set the FILE object for writing instrumentation data. Return 0 if set
176  * successfully or return 1 if failed.
177  *
178  * Sets the FILE object to be used for subsequent calls to
179  * \a __llvm_profile_write_file(). The profile file name set by environment
180  * variable, command-line option, or calls to \a  __llvm_profile_set_filename
181  * will be ignored.
182  *
183  * \c File will not be closed after a call to \a __llvm_profile_write_file() but
184  * it may be flushed. Passing NULL restores default behavior.
185  *
186  * If \c EnableMerge is nonzero, the runtime will always merge profiling data
187  * with the contents of the profiling file. If EnableMerge is zero, the runtime
188  * may still merge the data if it would have merged for another reason (for
189  * example, because of a %m specifier in the file name).
190  *
191  * Note: There may be multiple copies of the profile runtime (one for each
192  * instrumented image/DSO). This API only modifies the file object within the
193  * copy of the runtime available to the calling image.
194  *
195  * Warning: This is a no-op if EnableMerge is 0 in continuous mode (\ref
196  * __llvm_profile_is_continuous_mode_enabled), because disable merging requires
197  * copying the old profile file to new profile file and this function is usually
198  * used when the proess doesn't have permission to open file.
199  */
200 int __llvm_profile_set_file_object(FILE *File, int EnableMerge);
201 
202 /*! \brief Register to write instrumentation data to file at exit. */
203 int __llvm_profile_register_write_file_atexit(void);
204 
205 /*! \brief Initialize file handling. */
206 void __llvm_profile_initialize_file(void);
207 
208 /*! \brief Initialize the profile runtime. */
209 void __llvm_profile_initialize(void);
210 
211 /*!
212  * \brief Return path prefix (excluding the base filename) of the profile data.
213  * This is useful for users using \c -fprofile-generate=./path_prefix who do
214  * not care about the default raw profile name. It is also useful to collect
215  * more than more profile data files dumped in the same directory (Online
216  * merge mode is turned on for instrumented programs with shared libs).
217  * Side-effect: this API call will invoke malloc with dynamic memory allocation.
218  */
219 const char *__llvm_profile_get_path_prefix();
220 
221 /*!
222  * \brief Return filename (including path) of the profile data. Note that if the
223  * user calls __llvm_profile_set_filename later after invoking this interface,
224  * the actual file name may differ from what is returned here.
225  * Side-effect: this API call will invoke malloc with dynamic memory allocation
226  * (the returned pointer must be passed to `free` to avoid a leak).
227  *
228  * Note: There may be multiple copies of the profile runtime (one for each
229  * instrumented image/DSO). This API only retrieves the filename from the copy
230  * of the runtime available to the calling image.
231  */
232 const char *__llvm_profile_get_filename();
233 
234 /*! \brief Get the magic token for the file format. */
235 uint64_t __llvm_profile_get_magic(void);
236 
237 /*! \brief Get the version of the file format. */
238 uint64_t __llvm_profile_get_version(void);
239 
240 /*! \brief Get the number of entries in the profile data section. */
241 uint64_t __llvm_profile_get_num_data(const __llvm_profile_data *Begin,
242                                      const __llvm_profile_data *End);
243 
244 /*! \brief Get the size of the profile data section in bytes. */
245 uint64_t __llvm_profile_get_data_size(const __llvm_profile_data *Begin,
246                                       const __llvm_profile_data *End);
247 
248 /*! \brief Get the size in bytes of a single counter entry. */
249 size_t __llvm_profile_counter_entry_size(void);
250 
251 /*! \brief Get the number of entries in the profile counters section. */
252 uint64_t __llvm_profile_get_num_counters(const char *Begin, const char *End);
253 
254 /*! \brief Get the size of the profile counters section in bytes. */
255 uint64_t __llvm_profile_get_counters_size(const char *Begin, const char *End);
256 
257 /*! \brief Get the number of bytes in the profile bitmap section. */
258 uint64_t __llvm_profile_get_num_bitmap_bytes(const char *Begin,
259                                              const char *End);
260 
261 /*! \brief Get the size of the profile name section in bytes. */
262 uint64_t __llvm_profile_get_name_size(const char *Begin, const char *End);
263 
264 /*! \brief Get the number of virtual table profile data entries */
265 uint64_t __llvm_profile_get_num_vtable(const VTableProfData *Begin,
266                                        const VTableProfData *End);
267 
268 /*! \brief Get the size of virtual table profile data in bytes. */
269 uint64_t __llvm_profile_get_vtable_section_size(const VTableProfData *Begin,
270                                                 const VTableProfData *End);
271 
272 /* ! \brief Given the sizes of the data and counter information, computes the
273  * number of padding bytes before and after the counter section, as well as the
274  * number of padding bytes after other setions in the raw profile.
275  * Returns -1 upon errors and 0 upon success. Output parameters should be used
276  * iff return value is 0.
277  *
278  * Note: When mmap() mode is disabled, no padding bytes before/after counters
279  * are needed. However, in mmap() mode, the counter section in the raw profile
280  * must be page-aligned: this API computes the number of padding bytes
281  * needed to achieve that.
282  */
283 int __llvm_profile_get_padding_sizes_for_counters(
284     uint64_t DataSize, uint64_t CountersSize, uint64_t NumBitmapBytes,
285     uint64_t NamesSize, uint64_t VTableSize, uint64_t VNameSize,
286     uint64_t *PaddingBytesBeforeCounters, uint64_t *PaddingBytesAfterCounters,
287     uint64_t *PaddingBytesAfterBitmap, uint64_t *PaddingBytesAfterNames,
288     uint64_t *PaddingBytesAfterVTable, uint64_t *PaddingBytesAfterVNames);
289 
290 /*!
291  * \brief Set the flag that profile data has been dumped to the file.
292  * This is useful for users to disable dumping profile data to the file for
293  * certain processes in case the processes don't have permission to write to
294  * the disks, and trying to do so would result in side effects such as crashes.
295  */
296 void __llvm_profile_set_dumped();
297 
298 /*!
299  * This variable is defined in InstrProfilingRuntime.cpp as a hidden
300  * symbol. Its main purpose is to enable profile runtime user to
301  * bypass runtime initialization code -- if the client code explicitly
302  * define this variable, then InstProfileRuntime.o won't be linked in.
303  * Note that this variable's visibility needs to be hidden so that the
304  * definition of this variable in an instrumented shared library won't
305  * affect runtime initialization decision of the main program.
306  *  __llvm_profile_profile_runtime. */
307 COMPILER_RT_VISIBILITY extern int INSTR_PROF_PROFILE_RUNTIME_VAR;
308 
309 /*!
310  * This variable is defined in InstrProfilingVersionVar.c as a hidden symbol
311  * (except on Apple platforms where this symbol is checked by TAPI).  Its main
312  * purpose is to encode the raw profile version value and other format related
313  * information such as whether the profile is from IR based instrumentation. The
314  * variable is defined as weak so that compiler can emit an overriding
315  * definition depending on user option.
316  */
317 COMPILER_RT_VISIBILITY extern uint64_t
318     INSTR_PROF_RAW_VERSION_VAR; /* __llvm_profile_raw_version */
319 
320 /*!
321  * This variable is a weak symbol defined in InstrProfiling.c. It allows
322  * compiler instrumentation to provide overriding definition with value
323  * from compiler command line. This variable has default visibility.
324  */
325 extern char INSTR_PROF_PROFILE_NAME_VAR[1]; /* __llvm_profile_filename. */
326 
327 #endif /* PROFILE_INSTRPROFILING_H_ */
328