1 //===- FDRRecordProducer.h - XRay FDR Mode Record Producer ----------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 #ifndef LLVM_INCLUDE_LLVM_XRAY_FDRRECORDPRODUCER_H_
10 #define LLVM_INCLUDE_LLVM_XRAY_FDRRECORDPRODUCER_H_
11 
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 FileBasedRecordProducer : public RecordProducer {
29   const XRayFileHeader &Header;
30   DataExtractor &E;
31   uint32_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,uint32_t & OP)39   FileBasedRecordProducer(const XRayFileHeader &FH, DataExtractor &DE,
40                           uint32_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_INCLUDE_LLVM_XRAY_FDRRECORDPRODUCER_H_
52