xref: /freebsd/contrib/llvm-project/llvm/lib/ProfileData/MemProf.cpp (revision 02e9120893770924227138ba49df1edb3896112a)
1 #include "llvm/ProfileData/MemProf.h"
2 #include "llvm/ADT/SmallVector.h"
3 #include "llvm/IR/Function.h"
4 #include "llvm/ProfileData/InstrProf.h"
5 #include "llvm/Support/Endian.h"
6 #include "llvm/Support/EndianStream.h"
7 
8 namespace llvm {
9 namespace memprof {
10 
11 void IndexedMemProfRecord::serialize(const MemProfSchema &Schema,
12                                      raw_ostream &OS) {
13   using namespace support;
14 
15   endian::Writer LE(OS, little);
16 
17   LE.write<uint64_t>(AllocSites.size());
18   for (const IndexedAllocationInfo &N : AllocSites) {
19     LE.write<uint64_t>(N.CallStack.size());
20     for (const FrameId &Id : N.CallStack)
21       LE.write<FrameId>(Id);
22     N.Info.serialize(Schema, OS);
23   }
24 
25   // Related contexts.
26   LE.write<uint64_t>(CallSites.size());
27   for (const auto &Frames : CallSites) {
28     LE.write<uint64_t>(Frames.size());
29     for (const FrameId &Id : Frames)
30       LE.write<FrameId>(Id);
31   }
32 }
33 
34 IndexedMemProfRecord
35 IndexedMemProfRecord::deserialize(const MemProfSchema &Schema,
36                                   const unsigned char *Ptr) {
37   using namespace support;
38 
39   IndexedMemProfRecord Record;
40 
41   // Read the meminfo nodes.
42   const uint64_t NumNodes = endian::readNext<uint64_t, little, unaligned>(Ptr);
43   for (uint64_t I = 0; I < NumNodes; I++) {
44     IndexedAllocationInfo Node;
45     const uint64_t NumFrames =
46         endian::readNext<uint64_t, little, unaligned>(Ptr);
47     for (uint64_t J = 0; J < NumFrames; J++) {
48       const FrameId Id = endian::readNext<FrameId, little, unaligned>(Ptr);
49       Node.CallStack.push_back(Id);
50     }
51     Node.Info.deserialize(Schema, Ptr);
52     Ptr += PortableMemInfoBlock::serializedSize();
53     Record.AllocSites.push_back(Node);
54   }
55 
56   // Read the callsite information.
57   const uint64_t NumCtxs = endian::readNext<uint64_t, little, unaligned>(Ptr);
58   for (uint64_t J = 0; J < NumCtxs; J++) {
59     const uint64_t NumFrames =
60         endian::readNext<uint64_t, little, unaligned>(Ptr);
61     llvm::SmallVector<FrameId> Frames;
62     Frames.reserve(NumFrames);
63     for (uint64_t K = 0; K < NumFrames; K++) {
64       const FrameId Id = endian::readNext<FrameId, little, unaligned>(Ptr);
65       Frames.push_back(Id);
66     }
67     Record.CallSites.push_back(Frames);
68   }
69 
70   return Record;
71 }
72 
73 GlobalValue::GUID IndexedMemProfRecord::getGUID(const StringRef FunctionName) {
74   const auto Pos = FunctionName.find(".llvm.");
75 
76   // We use the function guid which we expect to be a uint64_t. At
77   // this time, it is the lower 64 bits of the md5 of the function
78   // name. Any suffix with .llvm. is trimmed since these are added by
79   // thinLTO global promotion. At the time the profile is consumed,
80   // these suffixes will not be present.
81   return Function::getGUID(FunctionName.take_front(Pos));
82 }
83 
84 Expected<MemProfSchema> readMemProfSchema(const unsigned char *&Buffer) {
85   using namespace support;
86 
87   const unsigned char *Ptr = Buffer;
88   const uint64_t NumSchemaIds =
89       endian::readNext<uint64_t, little, unaligned>(Ptr);
90   if (NumSchemaIds > static_cast<uint64_t>(Meta::Size)) {
91     return make_error<InstrProfError>(instrprof_error::malformed,
92                                       "memprof schema invalid");
93   }
94 
95   MemProfSchema Result;
96   for (size_t I = 0; I < NumSchemaIds; I++) {
97     const uint64_t Tag = endian::readNext<uint64_t, little, unaligned>(Ptr);
98     if (Tag >= static_cast<uint64_t>(Meta::Size)) {
99       return make_error<InstrProfError>(instrprof_error::malformed,
100                                         "memprof schema invalid");
101     }
102     Result.push_back(static_cast<Meta>(Tag));
103   }
104   // Advace the buffer to one past the schema if we succeeded.
105   Buffer = Ptr;
106   return Result;
107 }
108 
109 } // namespace memprof
110 } // namespace llvm
111