xref: /freebsd/contrib/llvm-project/llvm/include/llvm/XRay/FDRRecordProducer.h (revision 700637cbb5e582861067a11aaca4d053546871d2)
1 //===- FDRRecordProducer.h - XRay FDR Mode Record Producer ----------------===//
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 #ifndef LLVM_XRAY_FDRRECORDPRODUCER_H
9 #define LLVM_XRAY_FDRRECORDPRODUCER_H
10 
11 #include "llvm/Support/Compiler.h"
12 #include "llvm/Support/Error.h"
13 #include "llvm/XRay/FDRRecords.h"
14 #include "llvm/XRay/XRayRecord.h"
15 #include <memory>
16 
17 namespace llvm {
18 namespace xray {
19 
20 class RecordProducer {
21 public:
22   /// All producer implementations must yield either an Error or a non-nullptr
23   /// unique_ptr<Record>.
24   virtual Expected<std::unique_ptr<Record>> produce() = 0;
25   virtual ~RecordProducer() = default;
26 };
27 
28 class LLVM_ABI FileBasedRecordProducer : public RecordProducer {
29   const XRayFileHeader &Header;
30   DataExtractor &E;
31   uint64_t &OffsetPtr;
32   uint32_t CurrentBufferBytes = 0;
33 
34   // Helper function which gets the next record by speculatively reading through
35   // the log, finding a buffer extents record.
36   Expected<std::unique_ptr<Record>> findNextBufferExtent();
37 
38 public:
FileBasedRecordProducer(const XRayFileHeader & FH,DataExtractor & DE,uint64_t & OP)39   FileBasedRecordProducer(const XRayFileHeader &FH, DataExtractor &DE,
40                           uint64_t &OP)
41       : Header(FH), E(DE), OffsetPtr(OP) {}
42 
43   /// This producer encapsulates the logic for loading a File-backed
44   /// RecordProducer hidden behind a DataExtractor.
45   Expected<std::unique_ptr<Record>> produce() override;
46 };
47 
48 } // namespace xray
49 } // namespace llvm
50 
51 #endif // LLVM_XRAY_FDRRECORDPRODUCER_H
52