Revert "[ctx_profile] Profile reader and writer"

[mtrofin]

Reverts #91859

Buildbot failures.

[llvmbot]

@llvm/pr-subscribers-pgo

Author: Mircea Trofin (mtrofin)

Changes

Reverts llvm/llvm-project#91859

Buildbot failures.

---

Patch is 25.73 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/92199.diff

7 Files Affected:

• (removed) llvm/include/llvm/ProfileData/PGOCtxProfReader.h (-92)
• (removed) llvm/include/llvm/ProfileData/PGOCtxProfWriter.h (-91)
• (modified) llvm/lib/ProfileData/CMakeLists.txt (-2)
• (removed) llvm/lib/ProfileData/PGOCtxProfReader.cpp (-173)
• (removed) llvm/lib/ProfileData/PGOCtxProfWriter.cpp (-49)
• (modified) llvm/unittests/ProfileData/CMakeLists.txt (-1)
• (removed) llvm/unittests/ProfileData/PGOCtxProfReaderWriterTest.cpp (-255)

diff --git a/llvm/include/llvm/ProfileData/PGOCtxProfReader.h b/llvm/include/llvm/ProfileData/PGOCtxProfReader.h
deleted file mode 100644
index a19b3f51d642d..0000000000000
--- a/llvm/include/llvm/ProfileData/PGOCtxProfReader.h
+++ /dev/null
@@ -1,92 +0,0 @@
-//===--- PGOCtxProfReader.h - Contextual profile reader ---------*- C++ -*-===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-///
-/// \file
-///
-/// Reader for contextual iFDO profile, which comes in bitstream format.
-///
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_PROFILEDATA_CTXINSTRPROFILEREADER_H
-#define LLVM_PROFILEDATA_CTXINSTRPROFILEREADER_H
-
-#include "llvm/ADT/DenseSet.h"
-#include "llvm/Bitstream/BitstreamReader.h"
-#include "llvm/IR/GlobalValue.h"
-#include "llvm/ProfileData/PGOCtxProfWriter.h"
-#include "llvm/Support/Error.h"
-#include <map>
-#include <vector>
-
-namespace llvm {
-/// The loaded contextual profile, suitable for mutation during IPO passes. We
-/// generally expect a fraction of counters and of callsites to be populated.
-/// We continue to model counters as vectors, but callsites are modeled as a map
-/// of a map. The expectation is that, typically, there is a small number of
-/// indirect targets (usually, 1 for direct calls); but potentially a large
-/// number of callsites, and, as inlining progresses, the callsite count of a
-/// caller will grow.
-class PGOContextualProfile final {
-public:
-  using CallTargetMapTy = std::map<GlobalValue::GUID, PGOContextualProfile>;
-  using CallsiteMapTy = DenseMap<uint32_t, CallTargetMapTy>;
-
-private:
-  friend class PGOCtxProfileReader;
-  GlobalValue::GUID GUID = 0;
-  SmallVector<uint64_t, 16> Counters;
-  CallsiteMapTy Callsites;
-
-  PGOContextualProfile(GlobalValue::GUID G,
-                       SmallVectorImpl<uint64_t> &&Counters)
-      : GUID(G), Counters(std::move(Counters)) {}
-
-  Expected<PGOContextualProfile &>
-  getOrEmplace(uint32_t Index, GlobalValue::GUID G,
-               SmallVectorImpl<uint64_t> &&Counters);
-
-public:
-  PGOContextualProfile(const PGOContextualProfile &) = delete;
-  PGOContextualProfile &operator=(const PGOContextualProfile &) = delete;
-  PGOContextualProfile(PGOContextualProfile &&) = default;
-  PGOContextualProfile &operator=(PGOContextualProfile &&) = default;
-
-  GlobalValue::GUID guid() const { return GUID; }
-  const SmallVectorImpl<uint64_t> &counters() const { return Counters; }
-  const CallsiteMapTy &callsites() const { return Callsites; }
-  CallsiteMapTy &callsites() { return Callsites; }
-
-  bool hasCallsite(uint32_t I) const {
-    return Callsites.find(I) != Callsites.end();
-  }
-
-  const CallTargetMapTy &callsite(uint32_t I) const {
-    assert(hasCallsite(I) && "Callsite not found");
-    return Callsites.find(I)->second;
-  }
-  void getContainedGuids(DenseSet<GlobalValue::GUID> &Guids) const;
-};
-
-class PGOCtxProfileReader final {
-  BitstreamCursor &Cursor;
-  Expected<BitstreamEntry> advance();
-  Error readMetadata();
-  Error wrongValue(const Twine &);
-  Error unsupported(const Twine &);
-
-  Expected<std::pair<std::optional<uint32_t>, PGOContextualProfile>>
-  readContext(bool ExpectIndex);
-  bool canReadContext();
-
-public:
-  PGOCtxProfileReader(BitstreamCursor &Cursor) : Cursor(Cursor) {}
-
-  Expected<std::map<GlobalValue::GUID, PGOContextualProfile>> loadContexts();
-};
-} // namespace llvm
-#endif
diff --git a/llvm/include/llvm/ProfileData/PGOCtxProfWriter.h b/llvm/include/llvm/ProfileData/PGOCtxProfWriter.h
deleted file mode 100644
index 15578c51a4957..0000000000000
--- a/llvm/include/llvm/ProfileData/PGOCtxProfWriter.h
+++ /dev/null
@@ -1,91 +0,0 @@
-//===- PGOCtxProfWriter.h - Contextual Profile Writer -----------*- C++ -*-===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// This file declares a utility for writing a contextual profile to bitstream.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_PROFILEDATA_PGOCTXPROFWRITER_H_
-#define LLVM_PROFILEDATA_PGOCTXPROFWRITER_H_
-
-#include "llvm/Bitstream/BitstreamWriter.h"
-#include "llvm/ProfileData/CtxInstrContextNode.h"
-
-namespace llvm {
-enum PGOCtxProfileRecords { Invalid = 0, Version, Guid, CalleeIndex, Counters };
-
-enum PGOCtxProfileBlockIDs {
-  ProfileMetadataBlockID = 100,
-  ContextNodeBlockID = ProfileMetadataBlockID + 1
-};
-
-/// Write one or more ContextNodes to the provided raw_fd_stream.
-/// The caller must destroy the PGOCtxProfileWriter object before closing the
-/// stream.
-/// The design allows serializing a bunch of contexts embedded in some other
-/// file. The overall format is:
-///
-///  [... other data written to the stream...]
-///  SubBlock(ProfileMetadataBlockID)
-///   Version
-///   SubBlock(ContextNodeBlockID)
-///     [RECORDS]
-///     SubBlock(ContextNodeBlockID)
-///       [RECORDS]
-///       [... more SubBlocks]
-///     EndBlock
-///   EndBlock
-///
-/// The "RECORDS" are bitsream records. The IDs are in CtxProfileCodes (except)
-/// for Version, which is just for metadata). All contexts will have Guid and
-/// Counters, and all but the roots have CalleeIndex. The order in which the
-/// records appear does not matter, but they must precede any subcontexts,
-/// because that helps keep the reader code simpler.
-///
-/// Subblock containment captures the context->subcontext relationship. The
-/// "next()" relationship in the raw profile, between call targets of indirect
-/// calls, are just modeled as peer subblocks where the callee index is the
-/// same.
-///
-/// Versioning: the writer may produce additional records not known by the
-/// reader. The version number indicates a more structural change.
-/// The current version, in particular, is set up to expect optional extensions
-/// like value profiling - which would appear as additional records. For
-/// example, value profiling would produce a new record with a new record ID,
-/// containing the profiled values (much like the counters)
-class PGOCtxProfileWriter final {
-  SmallVector<char, 1 << 20> Buff;
-  BitstreamWriter Writer;
-
-  void writeCounters(const ctx_profile::ContextNode &Node);
-  void writeImpl(std::optional<uint32_t> CallerIndex,
-                 const ctx_profile::ContextNode &Node);
-
-public:
-  PGOCtxProfileWriter(raw_fd_stream &Out,
-                      std::optional<unsigned> VersionOverride = std::nullopt)
-      : Writer(Buff, &Out, 0) {
-    Writer.EnterSubblock(PGOCtxProfileBlockIDs::ProfileMetadataBlockID,
-                         CodeLen);
-    const auto Version = VersionOverride ? *VersionOverride : CurrentVersion;
-    Writer.EmitRecord(PGOCtxProfileRecords::Version,
-                      SmallVector<unsigned, 1>({Version}));
-  }
-
-  ~PGOCtxProfileWriter() { Writer.ExitBlock(); }
-
-  void write(const ctx_profile::ContextNode &);
-
-  // constants used in writing which a reader may find useful.
-  static constexpr unsigned CodeLen = 2;
-  static constexpr uint32_t CurrentVersion = 1;
-  static constexpr unsigned VBREncodingBits = 6;
-};
-
-} // namespace llvm
-#endif
diff --git a/llvm/lib/ProfileData/CMakeLists.txt b/llvm/lib/ProfileData/CMakeLists.txt
index 2397eebaf7b19..408f9ff01ec87 100644
--- a/llvm/lib/ProfileData/CMakeLists.txt
+++ b/llvm/lib/ProfileData/CMakeLists.txt
@@ -7,8 +7,6 @@ add_llvm_component_library(LLVMProfileData
   ItaniumManglingCanonicalizer.cpp
   MemProf.cpp
   MemProfReader.cpp
-  PGOCtxProfReader.cpp
-  PGOCtxProfWriter.cpp
   ProfileSummaryBuilder.cpp
   SampleProf.cpp
   SampleProfReader.cpp
diff --git a/llvm/lib/ProfileData/PGOCtxProfReader.cpp b/llvm/lib/ProfileData/PGOCtxProfReader.cpp
deleted file mode 100644
index 3710f2e4b8185..0000000000000
--- a/llvm/lib/ProfileData/PGOCtxProfReader.cpp
+++ /dev/null
@@ -1,173 +0,0 @@
-//===- PGOCtxProfReader.cpp - Contextual Instrumentation profile reader ---===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// Read a contextual profile into a datastructure suitable for maintenance
-// throughout IPO
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/ProfileData/PGOCtxProfReader.h"
-#include "llvm/Bitstream/BitCodeEnums.h"
-#include "llvm/Bitstream/BitstreamReader.h"
-#include "llvm/ProfileData/InstrProf.h"
-#include "llvm/ProfileData/PGOCtxProfWriter.h"
-#include "llvm/Support/Errc.h"
-#include "llvm/Support/Error.h"
-
-using namespace llvm;
-
-// FIXME(#92054) - these Error handling macros are (re-)invented in a few
-// places.
-#define EXPECT_OR_RET(LHS, RHS)                                                \
-  auto LHS = RHS;                                                              \
-  if (!LHS)                                                                    \
-    return LHS.takeError();
-
-#define RET_ON_ERR(EXPR)                                                       \
-  if (auto Err = (EXPR))                                                       \
-    return Err;
-
-Expected<PGOContextualProfile &>
-PGOContextualProfile::getOrEmplace(uint32_t Index, GlobalValue::GUID G,
-                                   SmallVectorImpl<uint64_t> &&Counters) {
-  auto [Iter, Inserted] = Callsites[Index].insert(
-      {G, PGOContextualProfile(G, std::move(Counters))});
-  if (!Inserted)
-    return make_error<InstrProfError>(instrprof_error::invalid_prof,
-                                      "Duplicate GUID for same callsite.");
-  return Iter->second;
-}
-
-void PGOContextualProfile::getContainedGuids(
-    DenseSet<GlobalValue::GUID> &Guids) const {
-  Guids.insert(GUID);
-  for (const auto &[_, Callsite] : Callsites)
-    for (const auto &[_, Callee] : Callsite)
-      Callee.getContainedGuids(Guids);
-}
-
-Expected<BitstreamEntry> PGOCtxProfileReader::advance() {
-  return Cursor.advance(BitstreamCursor::AF_DontAutoprocessAbbrevs);
-}
-
-Error PGOCtxProfileReader::wrongValue(const Twine &Msg) {
-  return make_error<InstrProfError>(instrprof_error::invalid_prof, Msg);
-}
-
-Error PGOCtxProfileReader::unsupported(const Twine &Msg) {
-  return make_error<InstrProfError>(instrprof_error::unsupported_version, Msg);
-}
-
-bool PGOCtxProfileReader::canReadContext() {
-  auto Blk = advance();
-  if (!Blk) {
-    consumeError(Blk.takeError());
-    return false;
-  }
-  return Blk->Kind == BitstreamEntry::SubBlock &&
-         Blk->ID == PGOCtxProfileBlockIDs::ContextNodeBlockID;
-}
-
-Expected<std::pair<std::optional<uint32_t>, PGOContextualProfile>>
-PGOCtxProfileReader::readContext(bool ExpectIndex) {
-  RET_ON_ERR(Cursor.EnterSubBlock(PGOCtxProfileBlockIDs::ContextNodeBlockID));
-
-  std::optional<ctx_profile::GUID> Guid;
-  std::optional<SmallVector<uint64_t, 16>> Counters;
-  std::optional<uint32_t> CallsiteIndex;
-
-  SmallVector<uint64_t, 1> RecordValues;
-
-  // We don't prescribe the order in which the records come in, and we are ok
-  // if other unsupported records appear. We seek in the current subblock until
-  // we get all we know.
-  auto GotAllWeNeed = [&]() {
-    return Guid.has_value() && Counters.has_value() &&
-           (!ExpectIndex || CallsiteIndex.has_value());
-  };
-  while (!GotAllWeNeed()) {
-    RecordValues.clear();
-    EXPECT_OR_RET(Entry, advance());
-    if (Entry->Kind != BitstreamEntry::Record)
-      return wrongValue(
-          "Expected records before encountering more subcontexts");
-    EXPECT_OR_RET(ReadRecord,
-                  Cursor.readRecord(bitc::UNABBREV_RECORD, RecordValues));
-    switch (*ReadRecord) {
-    case PGOCtxProfileRecords::Guid:
-      if (RecordValues.size() != 1)
-        return wrongValue("The GUID record should have exactly one value");
-      Guid = RecordValues[0];
-      break;
-    case PGOCtxProfileRecords::Counters:
-      Counters = std::move(RecordValues);
-      if (Counters->empty())
-        return wrongValue("Empty counters. At least the entry counter (one "
-                          "value) was expected");
-      break;
-    case PGOCtxProfileRecords::CalleeIndex:
-      if (!ExpectIndex)
-        return wrongValue("The root context should not have a callee index");
-      if (RecordValues.size() != 1)
-        return wrongValue("The callee index should have exactly one value");
-      CallsiteIndex = RecordValues[0];
-      break;
-    default:
-      // OK if we see records we do not understand, like records (profile
-      // components) introduced later.
-      break;
-    }
-  }
-
-  PGOContextualProfile Ret(*Guid, std::move(*Counters));
-
-  while (canReadContext()) {
-    EXPECT_OR_RET(SC, readContext(true));
-    auto &Targets = Ret.callsites()[*SC->first];
-    auto [_, Inserted] =
-        Targets.insert({SC->second.guid(), std::move(SC->second)});
-    if (!Inserted)
-      return wrongValue(
-          "Unexpected duplicate target (callee) at the same callsite.");
-  }
-  return std::make_pair(CallsiteIndex, std::move(Ret));
-}
-
-Error PGOCtxProfileReader::readMetadata() {
-  EXPECT_OR_RET(Blk, advance());
-  if (Blk->Kind != BitstreamEntry::SubBlock)
-    return unsupported("Expected Version record");
-  RET_ON_ERR(
-      Cursor.EnterSubBlock(PGOCtxProfileBlockIDs::ProfileMetadataBlockID));
-  EXPECT_OR_RET(MData, advance());
-  if (MData->Kind != BitstreamEntry::Record)
-    return unsupported("Expected Version record");
-
-  SmallVector<uint64_t, 1> Ver;
-  EXPECT_OR_RET(Code, Cursor.readRecord(bitc::UNABBREV_RECORD, Ver));
-  if (*Code != PGOCtxProfileRecords::Version)
-    return unsupported("Expected Version record");
-  if (Ver.size() != 1 || Ver[0] > PGOCtxProfileWriter::CurrentVersion)
-    return unsupported("Version " + Twine(*Code) +
-                       " is higher than supported version " +
-                       Twine(PGOCtxProfileWriter::CurrentVersion));
-  return Error::success();
-}
-
-Expected<std::map<GlobalValue::GUID, PGOContextualProfile>>
-PGOCtxProfileReader::loadContexts() {
-  std::map<GlobalValue::GUID, PGOContextualProfile> Ret;
-  RET_ON_ERR(readMetadata());
-  while (canReadContext()) {
-    EXPECT_OR_RET(E, readContext(false));
-    auto Key = E->second.guid();
-    if (!Ret.insert({Key, std::move(E->second)}).second)
-      return wrongValue("Duplicate roots");
-  }
-  return Ret;
-}
diff --git a/llvm/lib/ProfileData/PGOCtxProfWriter.cpp b/llvm/lib/ProfileData/PGOCtxProfWriter.cpp
deleted file mode 100644
index 5081797564469..0000000000000
--- a/llvm/lib/ProfileData/PGOCtxProfWriter.cpp
+++ /dev/null
@@ -1,49 +0,0 @@
-//===- PGOCtxProfWriter.cpp - Contextual Instrumentation profile writer ---===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// Write a contextual profile to bitstream.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/ProfileData/PGOCtxProfWriter.h"
-#include "llvm/Bitstream/BitCodeEnums.h"
-
-using namespace llvm;
-using namespace llvm::ctx_profile;
-
-void PGOCtxProfileWriter::writeCounters(const ContextNode &Node) {
-  Writer.EmitCode(bitc::UNABBREV_RECORD);
-  Writer.EmitVBR(PGOCtxProfileRecords::Counters, VBREncodingBits);
-  Writer.EmitVBR(Node.counters_size(), VBREncodingBits);
-  for (uint32_t I = 0U; I < Node.counters_size(); ++I)
-    Writer.EmitVBR64(Node.counters()[I], VBREncodingBits);
-}
-
-// recursively write all the subcontexts. We do need to traverse depth first to
-// model the context->subcontext implicitly, and since this captures call
-// stacks, we don't really need to be worried about stack overflow and we can
-// keep the implementation simple.
-void PGOCtxProfileWriter::writeImpl(std::optional<uint32_t> CallerIndex,
-                                    const ContextNode &Node) {
-  Writer.EnterSubblock(PGOCtxProfileBlockIDs::ContextNodeBlockID, CodeLen);
-  Writer.EmitRecord(PGOCtxProfileRecords::Guid,
-                    SmallVector<uint64_t, 1>{Node.guid()});
-  if (CallerIndex)
-    Writer.EmitRecord(PGOCtxProfileRecords::CalleeIndex,
-                      SmallVector<uint64_t, 1>{*CallerIndex});
-  writeCounters(Node);
-  for (uint32_t I = 0U; I < Node.callsites_size(); ++I)
-    for (const auto *Subcontext = Node.subContexts()[I]; Subcontext;
-         Subcontext = Subcontext->next())
-      writeImpl(I, *Subcontext);
-  Writer.ExitBlock();
-}
-
-void PGOCtxProfileWriter::write(const ContextNode &RootNode) {
-  writeImpl(std::nullopt, RootNode);
-}
diff --git a/llvm/unittests/ProfileData/CMakeLists.txt b/llvm/unittests/ProfileData/CMakeLists.txt
index c92642ded8282..ce3a0a45ccf18 100644
--- a/llvm/unittests/ProfileData/CMakeLists.txt
+++ b/llvm/unittests/ProfileData/CMakeLists.txt
@@ -13,7 +13,6 @@ add_llvm_unittest(ProfileDataTests
   InstrProfTest.cpp
   ItaniumManglingCanonicalizerTest.cpp
   MemProfTest.cpp
-  PGOCtxProfReaderWriterTest.cpp
   SampleProfTest.cpp
   SymbolRemappingReaderTest.cpp
   )
diff --git a/llvm/unittests/ProfileData/PGOCtxProfReaderWriterTest.cpp b/llvm/unittests/ProfileData/PGOCtxProfReaderWriterTest.cpp
deleted file mode 100644
index d2cdbb28e2fce..0000000000000
--- a/llvm/unittests/ProfileData/PGOCtxProfReaderWriterTest.cpp
+++ /dev/null
@@ -1,255 +0,0 @@
-//===-------------- PGOCtxProfReadWriteTest.cpp ---------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Bitstream/BitstreamReader.h"
-#include "llvm/ProfileData/CtxInstrContextNode.h"
-#include "llvm/ProfileData/PGOCtxProfReader.h"
-#include "llvm/ProfileData/PGOCtxProfWriter.h"
-#include "llvm/Support/Error.h"
-#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/Support/raw_ostream.h"
-#include "llvm/Testing/Support/SupportHelpers.h"
-#include "gtest/gtest.h"
-
-using namespace llvm;
-using namespace llvm::ctx_profile;
-
-class PGOCtxProfRWTest : public ::testing::Test {
-  std::vector<std::unique_ptr<char[]>> Nodes;
-  std::map<GUID, const ContextNode *> Roots;
-
-public:
-  ContextNode *createNode(GUID Guid, uint32_t NrCounters, uint32_t NrCallsites,
-                          ContextNode *Next = nullptr) {
-    auto AllocSize = ContextNode::getAllocSize(NrCounters, NrCallsites);
-    auto *Mem = Nodes.emplace_back(std::make_unique<char[]>(AllocSize)).get();
-    std::memset(Mem, 0, AllocSize);
-    auto *Ret = new (Mem) ContextNode(Guid, NrCounters, NrCallsites, Next);
-    return Ret;
-  }
-
-  void SetUp() override {
-    // Root (guid 1) has 2 callsites, one used for an indirect call to either
-    // guid 2 or 4.
-    // guid 2 calls guid 5
-    // guid 5 calls guid 2
-    // there's also a second root, guid3.
-    auto *Root1 = createNode(1, 2, 2);
-    Root1->counters()[0] = 10;
-    Root1->counters()[1] = 11;
-    Roots.insert({1, Root1});
-    auto *L1 = createNode(2, 1, 1);
-    L1->counters()[0] = 12;
-    Root1->subContexts()[1] = createNode(4, 3, 1, L1);
-    Root1->subContexts()[1]->counters()[0] = 13;
-    Root1->subContexts()[1]->counters()[1] = 14;
-    Root1->subContexts()[1]->counters()[2] = 15;
-
-    auto *L3 = createNode(5, 6, 3);
-    for (auto I = 0; I < 6; ++I)
-      L3->counters()[I] = 16 + I;
-    L1->subContexts()[0] = L3;
-    L3->subContexts()[2] = createNode(2, 1, 1);
-    L3->subContexts()[2]->counters()[0] = 30;
-    auto *Root2 = createNode(3, 1, 0);
-    Root2->counters()[0] = 40;
-    Roots.insert({3, Root2});
-  }
...
[truncated]