1 //===-- ThreadDecoder.cpp --======-----------------------------------------===// 2 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 3 // See https://llvm.org/LICENSE.txt for license information. 4 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 5 // 6 //===----------------------------------------------------------------------===// 7 8 #include "ThreadDecoder.h" 9 #include "../common/ThreadPostMortemTrace.h" 10 #include "LibiptDecoder.h" 11 #include "TraceIntelPT.h" 12 #include "llvm/Support/MemoryBuffer.h" 13 #include <optional> 14 #include <utility> 15 16 using namespace lldb; 17 using namespace lldb_private; 18 using namespace lldb_private::trace_intel_pt; 19 using namespace llvm; 20 21 ThreadDecoder::ThreadDecoder(const ThreadSP &thread_sp, TraceIntelPT &trace) 22 : m_thread_sp(thread_sp), m_trace(trace) {} 23 24 Expected<Optional<uint64_t>> ThreadDecoder::FindLowestTSC() { 25 Optional<uint64_t> lowest_tsc; 26 Error err = m_trace.OnThreadBufferRead( 27 m_thread_sp->GetID(), [&](llvm::ArrayRef<uint8_t> data) -> llvm::Error { 28 Expected<Optional<uint64_t>> tsc = FindLowestTSCInTrace(m_trace, data); 29 if (!tsc) 30 return tsc.takeError(); 31 lowest_tsc = *tsc; 32 return Error::success(); 33 }); 34 if (err) 35 return std::move(err); 36 return lowest_tsc; 37 } 38 39 Expected<DecodedThreadSP> ThreadDecoder::Decode() { 40 if (!m_decoded_thread.has_value()) { 41 if (Expected<DecodedThreadSP> decoded_thread = DoDecode()) { 42 m_decoded_thread = *decoded_thread; 43 } else { 44 return decoded_thread.takeError(); 45 } 46 } 47 return *m_decoded_thread; 48 } 49 50 llvm::Expected<DecodedThreadSP> ThreadDecoder::DoDecode() { 51 return m_trace.GetThreadTimer(m_thread_sp->GetID()) 52 .TimeTask("Decoding instructions", [&]() -> Expected<DecodedThreadSP> { 53 DecodedThreadSP decoded_thread_sp = std::make_shared<DecodedThread>( 54 m_thread_sp, m_trace.GetPerfZeroTscConversion()); 55 56 Error err = m_trace.OnThreadBufferRead( 57 m_thread_sp->GetID(), [&](llvm::ArrayRef<uint8_t> data) { 58 return DecodeSingleTraceForThread(*decoded_thread_sp, m_trace, 59 data); 60 }); 61 62 if (err) 63 return std::move(err); 64 return decoded_thread_sp; 65 }); 66 } 67