xref: /freebsd/contrib/llvm-project/compiler-rt/lib/profile/InstrProfilingMerge.c (revision 96190b4fef3b4a0cc3ca0606b0c4e3e69a5e6717)
1 /*===- InstrProfilingMerge.c - Profile in-process Merging  ---------------===*\
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 |* This file defines the API needed for in-process merging of profile data
9 |* stored in memory buffer.
10 \*===---------------------------------------------------------------------===*/
11 
12 #include "InstrProfiling.h"
13 #include "InstrProfilingInternal.h"
14 #include "InstrProfilingUtil.h"
15 
16 #define INSTR_PROF_VALUE_PROF_DATA
17 #include "profile/InstrProfData.inc"
18 
19 COMPILER_RT_VISIBILITY
20 void (*VPMergeHook)(ValueProfData *, __llvm_profile_data *);
21 
22 COMPILER_RT_VISIBILITY
23 uint64_t lprofGetLoadModuleSignature(void) {
24   /* A very fast way to compute a module signature.  */
25   uint64_t Version = __llvm_profile_get_version();
26   uint64_t NumCounters = __llvm_profile_get_num_counters(
27       __llvm_profile_begin_counters(), __llvm_profile_end_counters());
28   uint64_t NumData = __llvm_profile_get_num_data(__llvm_profile_begin_data(),
29                                                  __llvm_profile_end_data());
30   uint64_t NamesSize =
31       (uint64_t)(__llvm_profile_end_names() - __llvm_profile_begin_names());
32   uint64_t NumVnodes =
33       (uint64_t)(__llvm_profile_end_vnodes() - __llvm_profile_begin_vnodes());
34   const __llvm_profile_data *FirstD = __llvm_profile_begin_data();
35 
36   return (NamesSize << 40) + (NumCounters << 30) + (NumData << 20) +
37          (NumVnodes << 10) + (NumData > 0 ? FirstD->NameRef : 0) + Version +
38          __llvm_profile_get_magic();
39 }
40 
41 #ifdef __GNUC__
42 #pragma GCC diagnostic push
43 #pragma GCC diagnostic ignored "-Wcast-qual"
44 #elif defined(__clang__)
45 #pragma clang diagnostic push
46 #pragma clang diagnostic ignored "-Wcast-qual"
47 #endif
48 
49 /* Returns 1 if profile is not structurally compatible.  */
50 COMPILER_RT_VISIBILITY
51 int __llvm_profile_check_compatibility(const char *ProfileData,
52                                        uint64_t ProfileSize) {
53   __llvm_profile_header *Header = (__llvm_profile_header *)ProfileData;
54   __llvm_profile_data *SrcDataStart, *SrcDataEnd, *SrcData, *DstData;
55   SrcDataStart =
56       (__llvm_profile_data *)(ProfileData + sizeof(__llvm_profile_header) +
57                               Header->BinaryIdsSize);
58   SrcDataEnd = SrcDataStart + Header->NumData;
59 
60   if (ProfileSize < sizeof(__llvm_profile_header))
61     return 1;
62 
63   /* Check the header first.  */
64   if (Header->Magic != __llvm_profile_get_magic() ||
65       Header->Version != __llvm_profile_get_version() ||
66       Header->NumData !=
67           __llvm_profile_get_num_data(__llvm_profile_begin_data(),
68                                       __llvm_profile_end_data()) ||
69       Header->NumCounters !=
70           __llvm_profile_get_num_counters(__llvm_profile_begin_counters(),
71                                           __llvm_profile_end_counters()) ||
72       Header->NumBitmapBytes !=
73           __llvm_profile_get_num_bitmap_bytes(__llvm_profile_begin_bitmap(),
74                                               __llvm_profile_end_bitmap()) ||
75       Header->NamesSize !=
76           __llvm_profile_get_name_size(__llvm_profile_begin_names(),
77                                        __llvm_profile_end_names()) ||
78       Header->ValueKindLast != IPVK_Last)
79     return 1;
80 
81   if (ProfileSize <
82       sizeof(__llvm_profile_header) + Header->BinaryIdsSize +
83           Header->NumData * sizeof(__llvm_profile_data) + Header->NamesSize +
84           Header->NumCounters * __llvm_profile_counter_entry_size() +
85           Header->NumBitmapBytes)
86     return 1;
87 
88   for (SrcData = SrcDataStart,
89        DstData = (__llvm_profile_data *)__llvm_profile_begin_data();
90        SrcData < SrcDataEnd; ++SrcData, ++DstData) {
91     if (SrcData->NameRef != DstData->NameRef ||
92         SrcData->FuncHash != DstData->FuncHash ||
93         SrcData->NumCounters != DstData->NumCounters ||
94         SrcData->NumBitmapBytes != DstData->NumBitmapBytes)
95       return 1;
96   }
97 
98   /* Matched! */
99   return 0;
100 }
101 
102 static uintptr_t signextIfWin64(void *V) {
103 #ifdef _WIN64
104   return (uintptr_t)(int32_t)(uintptr_t)V;
105 #else
106   return (uintptr_t)V;
107 #endif
108 }
109 
110 COMPILER_RT_VISIBILITY
111 int __llvm_profile_merge_from_buffer(const char *ProfileData,
112                                      uint64_t ProfileSize) {
113   if (__llvm_profile_get_version() & VARIANT_MASK_TEMPORAL_PROF) {
114     PROF_ERR("%s\n",
115              "Temporal profiles do not support profile merging at runtime. "
116              "Instead, merge raw profiles using the llvm-profdata tool.");
117     return 1;
118   }
119 
120   __llvm_profile_data *SrcDataStart, *SrcDataEnd, *SrcData, *DstData;
121   __llvm_profile_header *Header = (__llvm_profile_header *)ProfileData;
122   char *SrcCountersStart, *DstCounter;
123   const char *SrcCountersEnd, *SrcCounter;
124   const char *SrcBitmapStart;
125   const char *SrcNameStart;
126   const char *SrcValueProfDataStart, *SrcValueProfData;
127   uintptr_t CountersDelta = Header->CountersDelta;
128   uintptr_t BitmapDelta = Header->BitmapDelta;
129 
130   SrcDataStart =
131       (__llvm_profile_data *)(ProfileData + sizeof(__llvm_profile_header) +
132                               Header->BinaryIdsSize);
133   SrcDataEnd = SrcDataStart + Header->NumData;
134   SrcCountersStart = (char *)SrcDataEnd;
135   SrcCountersEnd = SrcCountersStart +
136                    Header->NumCounters * __llvm_profile_counter_entry_size();
137   SrcBitmapStart = SrcCountersEnd;
138   SrcNameStart = SrcBitmapStart + Header->NumBitmapBytes;
139   SrcValueProfDataStart =
140       SrcNameStart + Header->NamesSize +
141       __llvm_profile_get_num_padding_bytes(Header->NamesSize);
142   if (SrcNameStart < SrcCountersStart || SrcNameStart < SrcBitmapStart)
143     return 1;
144 
145   // Merge counters by iterating the entire counter section when data section is
146   // empty due to correlation.
147   if (Header->NumData == 0) {
148     for (SrcCounter = SrcCountersStart,
149         DstCounter = __llvm_profile_begin_counters();
150          SrcCounter < SrcCountersEnd;) {
151       if (__llvm_profile_get_version() & VARIANT_MASK_BYTE_COVERAGE) {
152         *DstCounter &= *SrcCounter;
153       } else {
154         *(uint64_t *)DstCounter += *(uint64_t *)SrcCounter;
155       }
156       SrcCounter += __llvm_profile_counter_entry_size();
157       DstCounter += __llvm_profile_counter_entry_size();
158     }
159     return 0;
160   }
161 
162   for (SrcData = SrcDataStart,
163       DstData = (__llvm_profile_data *)__llvm_profile_begin_data(),
164       SrcValueProfData = SrcValueProfDataStart;
165        SrcData < SrcDataEnd; ++SrcData, ++DstData) {
166     // For the in-memory destination, CounterPtr is the distance from the start
167     // address of the data to the start address of the counter. On WIN64,
168     // CounterPtr is a truncated 32-bit value due to COFF limitation. Sign
169     // extend CounterPtr to get the original value.
170     char *DstCounters =
171         (char *)((uintptr_t)DstData + signextIfWin64(DstData->CounterPtr));
172     char *DstBitmap =
173         (char *)((uintptr_t)DstData + signextIfWin64(DstData->BitmapPtr));
174     unsigned NVK = 0;
175 
176     // SrcData is a serialized representation of the memory image. We need to
177     // compute the in-buffer counter offset from the in-memory address distance.
178     // The initial CountersDelta is the in-memory address difference
179     // start(__llvm_prf_cnts)-start(__llvm_prf_data), so SrcData->CounterPtr -
180     // CountersDelta computes the offset into the in-buffer counter section.
181     //
182     // On WIN64, CountersDelta is truncated as well, so no need for signext.
183     char *SrcCounters =
184         SrcCountersStart + ((uintptr_t)SrcData->CounterPtr - CountersDelta);
185     // CountersDelta needs to be decreased as we advance to the next data
186     // record.
187     CountersDelta -= sizeof(*SrcData);
188     unsigned NC = SrcData->NumCounters;
189     if (NC == 0)
190       return 1;
191     if (SrcCounters < SrcCountersStart || SrcCounters >= SrcNameStart ||
192         (SrcCounters + __llvm_profile_counter_entry_size() * NC) > SrcNameStart)
193       return 1;
194     for (unsigned I = 0; I < NC; I++) {
195       if (__llvm_profile_get_version() & VARIANT_MASK_BYTE_COVERAGE) {
196         // A value of zero signifies the function is covered.
197         DstCounters[I] &= SrcCounters[I];
198       } else {
199         ((uint64_t *)DstCounters)[I] += ((uint64_t *)SrcCounters)[I];
200       }
201     }
202 
203     const char *SrcBitmap =
204         SrcBitmapStart + ((uintptr_t)SrcData->BitmapPtr - BitmapDelta);
205     // BitmapDelta also needs to be decreased as we advance to the next data
206     // record.
207     BitmapDelta -= sizeof(*SrcData);
208     unsigned NB = SrcData->NumBitmapBytes;
209     // NumBitmapBytes may legitimately be 0. Just keep going.
210     if (NB != 0) {
211       if (SrcBitmap < SrcBitmapStart || (SrcBitmap + NB) > SrcNameStart)
212         return 1;
213       // Merge Src and Dst Bitmap bytes by simply ORing them together.
214       for (unsigned I = 0; I < NB; I++)
215         DstBitmap[I] |= SrcBitmap[I];
216     }
217 
218     /* Now merge value profile data. */
219     if (!VPMergeHook)
220       continue;
221 
222     for (unsigned I = 0; I <= IPVK_Last; I++)
223       NVK += (SrcData->NumValueSites[I] != 0);
224 
225     if (!NVK)
226       continue;
227 
228     if (SrcValueProfData >= ProfileData + ProfileSize)
229       return 1;
230     VPMergeHook((ValueProfData *)SrcValueProfData, DstData);
231     SrcValueProfData =
232         SrcValueProfData + ((ValueProfData *)SrcValueProfData)->TotalSize;
233   }
234 
235   return 0;
236 }
237 
238 #ifdef __GNUC__
239 #pragma GCC diagnostic pop
240 #elif defined(__clang__)
241 #pragma clang diagnostic pop
242 #endif
243