xref: /freebsd/contrib/llvm-project/llvm/lib/ProfileData/MemProf.cpp (revision a0ca4af9455b844c5e094fc1b09b1390ffa979fc)
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/ProfileData/SampleProf.h"
6 #include "llvm/Support/Endian.h"
7 #include "llvm/Support/EndianStream.h"
8 
9 namespace llvm {
10 namespace memprof {
11 
12 void IndexedMemProfRecord::serialize(const MemProfSchema &Schema,
13                                      raw_ostream &OS) {
14   using namespace support;
15 
16   endian::Writer LE(OS, llvm::endianness::little);
17 
18   LE.write<uint64_t>(AllocSites.size());
19   for (const IndexedAllocationInfo &N : AllocSites) {
20     LE.write<uint64_t>(N.CallStack.size());
21     for (const FrameId &Id : N.CallStack)
22       LE.write<FrameId>(Id);
23     N.Info.serialize(Schema, OS);
24   }
25 
26   // Related contexts.
27   LE.write<uint64_t>(CallSites.size());
28   for (const auto &Frames : CallSites) {
29     LE.write<uint64_t>(Frames.size());
30     for (const FrameId &Id : Frames)
31       LE.write<FrameId>(Id);
32   }
33 }
34 
35 IndexedMemProfRecord
36 IndexedMemProfRecord::deserialize(const MemProfSchema &Schema,
37                                   const unsigned char *Ptr) {
38   using namespace support;
39 
40   IndexedMemProfRecord Record;
41 
42   // Read the meminfo nodes.
43   const uint64_t NumNodes =
44       endian::readNext<uint64_t, llvm::endianness::little, unaligned>(Ptr);
45   for (uint64_t I = 0; I < NumNodes; I++) {
46     IndexedAllocationInfo Node;
47     const uint64_t NumFrames =
48         endian::readNext<uint64_t, llvm::endianness::little, unaligned>(Ptr);
49     for (uint64_t J = 0; J < NumFrames; J++) {
50       const FrameId Id =
51           endian::readNext<FrameId, llvm::endianness::little, unaligned>(Ptr);
52       Node.CallStack.push_back(Id);
53     }
54     Node.Info.deserialize(Schema, Ptr);
55     Ptr += PortableMemInfoBlock::serializedSize();
56     Record.AllocSites.push_back(Node);
57   }
58 
59   // Read the callsite information.
60   const uint64_t NumCtxs =
61       endian::readNext<uint64_t, llvm::endianness::little, unaligned>(Ptr);
62   for (uint64_t J = 0; J < NumCtxs; J++) {
63     const uint64_t NumFrames =
64         endian::readNext<uint64_t, llvm::endianness::little, unaligned>(Ptr);
65     llvm::SmallVector<FrameId> Frames;
66     Frames.reserve(NumFrames);
67     for (uint64_t K = 0; K < NumFrames; K++) {
68       const FrameId Id =
69           endian::readNext<FrameId, llvm::endianness::little, unaligned>(Ptr);
70       Frames.push_back(Id);
71     }
72     Record.CallSites.push_back(Frames);
73   }
74 
75   return Record;
76 }
77 
78 GlobalValue::GUID IndexedMemProfRecord::getGUID(const StringRef FunctionName) {
79   // Canonicalize the function name to drop suffixes such as ".llvm.". Note
80   // we do not drop any ".__uniq." suffixes, as getCanonicalFnName does not drop
81   // those by default. This is by design to differentiate internal linkage
82   // functions during matching. By dropping the other suffixes we can then match
83   // functions in the profile use phase prior to their addition. Note that this
84   // applies to both instrumented and sampled function names.
85   StringRef CanonicalName =
86       sampleprof::FunctionSamples::getCanonicalFnName(FunctionName);
87 
88   // We use the function guid which we expect to be a uint64_t. At
89   // this time, it is the lower 64 bits of the md5 of the canonical
90   // function name.
91   return Function::getGUID(CanonicalName);
92 }
93 
94 Expected<MemProfSchema> readMemProfSchema(const unsigned char *&Buffer) {
95   using namespace support;
96 
97   const unsigned char *Ptr = Buffer;
98   const uint64_t NumSchemaIds =
99       endian::readNext<uint64_t, llvm::endianness::little, unaligned>(Ptr);
100   if (NumSchemaIds > static_cast<uint64_t>(Meta::Size)) {
101     return make_error<InstrProfError>(instrprof_error::malformed,
102                                       "memprof schema invalid");
103   }
104 
105   MemProfSchema Result;
106   for (size_t I = 0; I < NumSchemaIds; I++) {
107     const uint64_t Tag =
108         endian::readNext<uint64_t, llvm::endianness::little, unaligned>(Ptr);
109     if (Tag >= static_cast<uint64_t>(Meta::Size)) {
110       return make_error<InstrProfError>(instrprof_error::malformed,
111                                         "memprof schema invalid");
112     }
113     Result.push_back(static_cast<Meta>(Tag));
114   }
115   // Advace the buffer to one past the schema if we succeeded.
116   Buffer = Ptr;
117   return Result;
118 }
119 
120 } // namespace memprof
121 } // namespace llvm
122