1//===- Trace.h - XRay Trace Abstraction -----------------------------------===//
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//
9// Defines the XRay Trace class representing records in an XRay trace file.
10//
11//===----------------------------------------------------------------------===//
12#ifndef LLVM_XRAY_TRACE_H
13#define LLVM_XRAY_TRACE_H
14
15#include <cstdint>
16#include <vector>
17
18#include "llvm/ADT/StringRef.h"
19#include "llvm/Support/DataExtractor.h"
20#include "llvm/Support/Error.h"
21#include "llvm/XRay/XRayRecord.h"
22
23namespace llvm {
24namespace xray {
25
26/// A Trace object represents the records that have been loaded from XRay
27/// log files generated by instrumented binaries. We encapsulate the logic of
28/// reading the traces in factory functions that populate the Trace object
29/// appropriately.
30///
31/// Trace objects provide an accessor to an XRayFileHeader which says more about
32/// details of the file from which the XRay trace was loaded from.
33///
34/// Usage:
35///
36/// if (auto TraceOrErr = loadTraceFile("xray-log.something.xray")) {
37/// auto& T = *TraceOrErr;
38/// // T.getFileHeader() will provide information from the trace header.
39/// for (const XRayRecord &R : T) {
40/// // ... do something with R here.
41/// }
42/// } else {
43/// // Handle the error here.
44/// }
45///
46class Trace {
47 XRayFileHeader FileHeader;
48 using RecordVector = std::vector<XRayRecord>;
49 RecordVector Records;
50
51 typedef std::vector<XRayRecord>::const_iterator citerator;
52
53 friend Expected<Trace> loadTrace(const DataExtractor &, bool);
54
55public:
56 using size_type = RecordVector::size_type;
57 using value_type = RecordVector::value_type;
58 using const_iterator = RecordVector::const_iterator;
59
60 /// Provides access to the loaded XRay trace file header.
61 const XRayFileHeader &getFileHeader() const { return FileHeader; }
62
63 const_iterator begin() const { return Records.begin(); }
64 const_iterator end() const { return Records.end(); }
65 bool empty() const { return Records.empty(); }
66 size_type size() const { return Records.size(); }
67};
68
69/// This function will attempt to load XRay trace records from the provided
70/// |Filename|.
71Expected<Trace> loadTraceFile(StringRef Filename, bool Sort = false);
72
73/// This function will attempt to load XRay trace records from the provided
74/// DataExtractor.
75Expected<Trace> loadTrace(const DataExtractor &Extractor, bool Sort = false);
76
77} // namespace xray
78} // namespace llvm
79
80#endif // LLVM_XRAY_TRACE_H
81

source code of llvm/include/llvm/XRay/Trace.h