xref: /freebsd/contrib/llvm-project/compiler-rt/lib/profile/InstrProfiling.c (revision a0ca4af9455b844c5e094fc1b09b1390ffa979fc)
1 /*===- InstrProfiling.c - 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 // Note: This is linked into the Darwin kernel, and must remain compatible
10 // with freestanding compilation. See `darwin_add_builtin_libraries`.
11 
12 #include <limits.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 
17 #include "InstrProfiling.h"
18 #include "InstrProfilingInternal.h"
19 
20 #define INSTR_PROF_VALUE_PROF_DATA
21 #include "profile/InstrProfData.inc"
22 
23 static uint32_t __llvm_profile_global_timestamp = 1;
24 
25 COMPILER_RT_VISIBILITY
26 void INSTR_PROF_PROFILE_SET_TIMESTAMP(uint64_t *Probe) {
27   if (*Probe == 0 || *Probe == (uint64_t)-1)
28     *Probe = __llvm_profile_global_timestamp++;
29 }
30 
31 COMPILER_RT_VISIBILITY uint64_t __llvm_profile_get_magic(void) {
32   return sizeof(void *) == sizeof(uint64_t) ? (INSTR_PROF_RAW_MAGIC_64)
33                                             : (INSTR_PROF_RAW_MAGIC_32);
34 }
35 
36 COMPILER_RT_VISIBILITY void __llvm_profile_set_dumped(void) {
37   lprofSetProfileDumped(1);
38 }
39 
40 /* Return the number of bytes needed to add to SizeInBytes to make it
41  *   the result a multiple of 8.
42  */
43 COMPILER_RT_VISIBILITY uint8_t
44 __llvm_profile_get_num_padding_bytes(uint64_t SizeInBytes) {
45   return 7 & (sizeof(uint64_t) - SizeInBytes % sizeof(uint64_t));
46 }
47 
48 COMPILER_RT_VISIBILITY uint64_t __llvm_profile_get_version(void) {
49   return INSTR_PROF_RAW_VERSION_VAR;
50 }
51 
52 COMPILER_RT_VISIBILITY void __llvm_profile_reset_counters(void) {
53   if (__llvm_profile_get_version() & VARIANT_MASK_TEMPORAL_PROF)
54     __llvm_profile_global_timestamp = 1;
55 
56   char *I = __llvm_profile_begin_counters();
57   char *E = __llvm_profile_end_counters();
58 
59   char ResetValue =
60       (__llvm_profile_get_version() & VARIANT_MASK_BYTE_COVERAGE) ? 0xFF : 0;
61   memset(I, ResetValue, E - I);
62 
63   I = __llvm_profile_begin_bitmap();
64   E = __llvm_profile_end_bitmap();
65   memset(I, 0x0, E - I);
66 
67   const __llvm_profile_data *DataBegin = __llvm_profile_begin_data();
68   const __llvm_profile_data *DataEnd = __llvm_profile_end_data();
69   const __llvm_profile_data *DI;
70   for (DI = DataBegin; DI < DataEnd; ++DI) {
71     uint64_t CurrentVSiteCount = 0;
72     uint32_t VKI, i;
73     if (!DI->Values)
74       continue;
75 
76     ValueProfNode **ValueCounters = (ValueProfNode **)DI->Values;
77 
78     for (VKI = IPVK_First; VKI <= IPVK_Last; ++VKI)
79       CurrentVSiteCount += DI->NumValueSites[VKI];
80 
81     for (i = 0; i < CurrentVSiteCount; ++i) {
82       ValueProfNode *CurrVNode = ValueCounters[i];
83 
84       while (CurrVNode) {
85         CurrVNode->Count = 0;
86         CurrVNode = CurrVNode->Next;
87       }
88     }
89   }
90   lprofSetProfileDumped(0);
91 }
92