1*0fca6ea1SDimitry Andric //===- PGOCtxProfWriter.cpp - Contextual Instrumentation profile writer ---===// 2*0fca6ea1SDimitry Andric // 3*0fca6ea1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*0fca6ea1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 5*0fca6ea1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*0fca6ea1SDimitry Andric // 7*0fca6ea1SDimitry Andric //===----------------------------------------------------------------------===// 8*0fca6ea1SDimitry Andric // 9*0fca6ea1SDimitry Andric // Write a contextual profile to bitstream. 10*0fca6ea1SDimitry Andric // 11*0fca6ea1SDimitry Andric //===----------------------------------------------------------------------===// 12*0fca6ea1SDimitry Andric 13*0fca6ea1SDimitry Andric #include "llvm/ProfileData/PGOCtxProfWriter.h" 14*0fca6ea1SDimitry Andric #include "llvm/Bitstream/BitCodeEnums.h" 15*0fca6ea1SDimitry Andric 16*0fca6ea1SDimitry Andric using namespace llvm; 17*0fca6ea1SDimitry Andric using namespace llvm::ctx_profile; 18*0fca6ea1SDimitry Andric 19*0fca6ea1SDimitry Andric void PGOCtxProfileWriter::writeCounters(const ContextNode &Node) { 20*0fca6ea1SDimitry Andric Writer.EmitCode(bitc::UNABBREV_RECORD); 21*0fca6ea1SDimitry Andric Writer.EmitVBR(PGOCtxProfileRecords::Counters, VBREncodingBits); 22*0fca6ea1SDimitry Andric Writer.EmitVBR(Node.counters_size(), VBREncodingBits); 23*0fca6ea1SDimitry Andric for (uint32_t I = 0U; I < Node.counters_size(); ++I) 24*0fca6ea1SDimitry Andric Writer.EmitVBR64(Node.counters()[I], VBREncodingBits); 25*0fca6ea1SDimitry Andric } 26*0fca6ea1SDimitry Andric 27*0fca6ea1SDimitry Andric // recursively write all the subcontexts. We do need to traverse depth first to 28*0fca6ea1SDimitry Andric // model the context->subcontext implicitly, and since this captures call 29*0fca6ea1SDimitry Andric // stacks, we don't really need to be worried about stack overflow and we can 30*0fca6ea1SDimitry Andric // keep the implementation simple. 31*0fca6ea1SDimitry Andric void PGOCtxProfileWriter::writeImpl(std::optional<uint32_t> CallerIndex, 32*0fca6ea1SDimitry Andric const ContextNode &Node) { 33*0fca6ea1SDimitry Andric Writer.EnterSubblock(PGOCtxProfileBlockIDs::ContextNodeBlockID, CodeLen); 34*0fca6ea1SDimitry Andric Writer.EmitRecord(PGOCtxProfileRecords::Guid, 35*0fca6ea1SDimitry Andric SmallVector<uint64_t, 1>{Node.guid()}); 36*0fca6ea1SDimitry Andric if (CallerIndex) 37*0fca6ea1SDimitry Andric Writer.EmitRecord(PGOCtxProfileRecords::CalleeIndex, 38*0fca6ea1SDimitry Andric SmallVector<uint64_t, 1>{*CallerIndex}); 39*0fca6ea1SDimitry Andric writeCounters(Node); 40*0fca6ea1SDimitry Andric for (uint32_t I = 0U; I < Node.callsites_size(); ++I) 41*0fca6ea1SDimitry Andric for (const auto *Subcontext = Node.subContexts()[I]; Subcontext; 42*0fca6ea1SDimitry Andric Subcontext = Subcontext->next()) 43*0fca6ea1SDimitry Andric writeImpl(I, *Subcontext); 44*0fca6ea1SDimitry Andric Writer.ExitBlock(); 45*0fca6ea1SDimitry Andric } 46*0fca6ea1SDimitry Andric 47*0fca6ea1SDimitry Andric void PGOCtxProfileWriter::write(const ContextNode &RootNode) { 48*0fca6ea1SDimitry Andric writeImpl(std::nullopt, RootNode); 49*0fca6ea1SDimitry Andric } 50