[PGO] Clang part of change for context-sensitive PGO (part1)

Part 1 of CSPGO change in Clang. This includes changes in clang options
and calls to llvm PassManager. Tests will be committed in part2.
This change needs the PassManager change in llvm.

Differential Revision: https://reviews.llvm.org/D54176

llvm-svn: 355331

diff --git a/clang/docs/UsersManual.rst b/clang/docs/UsersManual.rst
index f004f20..88cb72c 100644 (file)
--- a/clang/docs/UsersManual.rst
+++ b/clang/docs/UsersManual.rst
@@ -1745,7 +1745,8 @@ controlled by the GCC-compatible flags ``-fprofile-generate`` and
 ``-fprofile-use``. Although these flags are semantically equivalent to
 their GCC counterparts, they *do not* handle GCC-compatible profiles.
 They are only meant to implement GCC's semantics with respect to
-profile creation and use.
+profile creation and use. Flag ``-fcs-profile-generate`` also instruments
+programs using the same instrumentation method as ``-fprofile-generate``.
 
 .. option:: -fprofile-generate[=<dirname>]
 
@@ -1778,6 +1779,45 @@ profile creation and use.
  ``LLVM_PROFILE_FILE`` can still be used to override
  the directory and filename for the profile file at runtime.
 
+.. option:: -fcs-profile-generate[=<dirname>]
+
+  The ``-fcs-profile-generate`` and ``-fcs-profile-generate=`` flags will use
+  the same instrumentation method, and generate the same profile as in the
+  ``-fprofile-generate`` and ``-fprofile-generate=`` flags. The difference is
+  that the instrumentation is performed after inlining so that the resulted
+  profile has a better context sensitive information. They cannot be used
+  together with ``-fprofile-generate`` and ``-fprofile-generate=`` flags.
+  They are typically used in conjunction with ``-fprofile-use`` flag.
+  The profile generated by ``-fcs-profile-generate`` and ``-fprofile-generate``
+  can be merged by llvm-profdata. A use example:
+
+  .. code-block:: console
+
+    $ clang++ -O2 -fprofile-generate=yyy/zzz code.cc -o code
+    $ ./code
+    $ llvm-profdata merge -output=code.profdata yyy/zzz/
+
+  The first few steps are the same as that in ``-fprofile-generate``
+  compilation. Then perform a second round of instrumentation.
+
+  .. code-block:: console
+
+    $ clang++ -O2 -fprofile-use=code.profdata -fcs-profile-generate=sss/ttt \
+      -o cs_code
+    $ ./cs_code
+    $ llvm-profdata merge -output=cs_code.profdata sss/ttt code.profdata
+
+  The resulted ``cs_code.prodata`` combines ``code.profdata`` and the profile
+  generated from binary ``cs_code``. Profile ``cs_code.profata`` can be used by
+  ``-fprofile-use`` compilaton.
+
+  .. code-block:: console
+
+    $ clang++ -O2 -fprofile-use=cs_code.profdata
+
+  The above command will read both profiles to the compiler at the identical
+  point of instrumenations.
+
 .. option:: -fprofile-use[=<pathname>]
 
   Without any other arguments, ``-fprofile-use`` behaves identically to

diff --git a/clang/include/clang/Basic/CodeGenOptions.h b/clang/include/clang/Basic/CodeGenOptions.h
index 5c8abe3..fc284f8 100644 (file)
--- a/clang/include/clang/Basic/CodeGenOptions.h
+++ b/clang/include/clang/Basic/CodeGenOptions.h
@@ -100,6 +100,7 @@ public:
     ProfileClangInstr, // Clang instrumentation to generate execution counts
                        // to use with PGO.
     ProfileIRInstr,    // IR level PGO instrumentation in LLVM.
+    ProfileCSIRInstr, // IR level PGO context sensitive instrumentation in LLVM.
   };
 
   enum EmbedBitcodeKind {
@@ -203,8 +204,8 @@ public:
   /// A list of linker options to embed in the object file.
   std::vector<std::string> LinkerOptions;
 
-  /// Name of the profile file to use as output for -fprofile-instr-generate
-  /// and -fprofile-generate.
+  /// Name of the profile file to use as output for -fprofile-instr-generate,
+  /// -fprofile-generate, and -fcs-profile-generate.
   std::string InstrProfileOutput;
 
   /// Name of the profile file to use with -fprofile-sample-use.
@@ -318,6 +319,11 @@ public:
     return getProfileInstr() == ProfileIRInstr;
   }
 
+  /// Check if CS IR level profile instrumentation is on.
+  bool hasProfileCSIRInstr() const {
+    return getProfileInstr() == ProfileCSIRInstr;
+  }
+
   /// Check if Clang profile use is on.
   bool hasProfileClangUse() const {
     return getProfileUse() == ProfileClangInstr;
@@ -325,9 +331,12 @@ public:
 
   /// Check if IR level profile use is on.
   bool hasProfileIRUse() const {
-    return getProfileUse() == ProfileIRInstr;
+    return getProfileUse() == ProfileIRInstr ||
+           getProfileUse() == ProfileCSIRInstr;
   }
 
+  /// Check if CSIR profile use is on.
+  bool hasProfileCSIRUse() const { return getProfileUse() == ProfileCSIRInstr; }
 };
 
 }  // end namespace clang

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 8a68e68..7264c81 100644 (file)
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -747,6 +747,12 @@ def fprofile_generate : Flag<["-"], "fprofile-generate">,
 def fprofile_generate_EQ : Joined<["-"], "fprofile-generate=">,
     Group<f_Group>, Flags<[DriverOption]>, MetaVarName<"<directory>">,
     HelpText<"Generate instrumented code to collect execution counts into <directory>/default.profraw (overridden by LLVM_PROFILE_FILE env var)">;
+def fcs_profile_generate : Flag<["-"], "fcs-profile-generate">,
+    Group<f_Group>, Flags<[DriverOption]>,
+    HelpText<"Generate instrumented code to collect context sensitive execution counts into default.profraw (overridden by LLVM_PROFILE_FILE env var)">;
+def fcs_profile_generate_EQ : Joined<["-"], "fcs-profile-generate=">,
+    Group<f_Group>, Flags<[DriverOption]>, MetaVarName<"<directory>">,
+    HelpText<"Generate instrumented code to collect context sensitive execution counts into <directory>/default.profraw (overridden by LLVM_PROFILE_FILE env var)">;
 def fprofile_use : Flag<["-"], "fprofile-use">, Group<f_Group>,
     Alias<fprofile_instr_use>;
 def fprofile_use_EQ : Joined<["-"], "fprofile-use=">,

diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 2f71664..9b0432d 100644 (file)
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -687,17 +687,33 @@ void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
     // the driver level.
     Options.Atomic = LangOpts.Sanitize.has(SanitizerKind::Thread);
 
-    MPM.add(createInstrProfilingLegacyPass(Options));
+    MPM.add(createInstrProfilingLegacyPass(Options, false));
   }
+  bool hasIRInstr = false;
   if (CodeGenOpts.hasProfileIRInstr()) {
     PMBuilder.EnablePGOInstrGen = true;
+    hasIRInstr = true;
+  }
+  if (CodeGenOpts.hasProfileCSIRInstr()) {
+    assert(!CodeGenOpts.hasProfileCSIRUse() &&
+           "Cannot have both CSProfileUse pass and CSProfileGen pass at the "
+           "same time");
+    assert(!hasIRInstr &&
+           "Cannot have both ProfileGen pass and CSProfileGen pass at the "
+           "same time");
+    PMBuilder.EnablePGOCSInstrGen = true;
+    hasIRInstr = true;
+  }
+  if (hasIRInstr) {
     if (!CodeGenOpts.InstrProfileOutput.empty())
       PMBuilder.PGOInstrGen = CodeGenOpts.InstrProfileOutput;
     else
       PMBuilder.PGOInstrGen = DefaultProfileGenName;
   }
-  if (CodeGenOpts.hasProfileIRUse())
+  if (CodeGenOpts.hasProfileIRUse()) {
     PMBuilder.PGOInstrUse = CodeGenOpts.ProfileInstrumentUsePath;
+    PMBuilder.EnablePGOCSInstrUse = CodeGenOpts.hasProfileCSIRUse();
+  }
 
   if (!CodeGenOpts.SampleProfileFile.empty())
     PMBuilder.PGOSampleUse = CodeGenOpts.SampleProfileFile;
@@ -970,21 +986,48 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
     PGOOpt = PGOOptions(CodeGenOpts.InstrProfileOutput.empty()
                             ? DefaultProfileGenName
                             : CodeGenOpts.InstrProfileOutput,
-                        "", "", "", true,
+                        "", "", PGOOptions::IRInstr, PGOOptions::NoCSAction,
                         CodeGenOpts.DebugInfoForProfiling);
-  else if (CodeGenOpts.hasProfileIRUse())
+  else if (CodeGenOpts.hasProfileIRUse()) {
     // -fprofile-use.
-    PGOOpt = PGOOptions("", CodeGenOpts.ProfileInstrumentUsePath, "",
-                        CodeGenOpts.ProfileRemappingFile, false,
-                        CodeGenOpts.DebugInfoForProfiling);
-  else if (!CodeGenOpts.SampleProfileFile.empty())
+    auto CSAction = CodeGenOpts.hasProfileCSIRUse() ? PGOOptions::CSIRUse
+                                                    : PGOOptions::NoCSAction;
+    PGOOpt = PGOOptions(CodeGenOpts.ProfileInstrumentUsePath, "",
+                        CodeGenOpts.ProfileRemappingFile, PGOOptions::IRUse,
+                        CSAction, CodeGenOpts.DebugInfoForProfiling);
+  } else if (!CodeGenOpts.SampleProfileFile.empty())
     // -fprofile-sample-use
-    PGOOpt = PGOOptions("", "", CodeGenOpts.SampleProfileFile,
-                        CodeGenOpts.ProfileRemappingFile, false,
-                        CodeGenOpts.DebugInfoForProfiling);
+    PGOOpt =
+        PGOOptions(CodeGenOpts.SampleProfileFile, "",
+                   CodeGenOpts.ProfileRemappingFile, PGOOptions::SampleUse,
+                   PGOOptions::NoCSAction, CodeGenOpts.DebugInfoForProfiling);
   else if (CodeGenOpts.DebugInfoForProfiling)
     // -fdebug-info-for-profiling
-    PGOOpt = PGOOptions("", "", "", "", false, true);
+    PGOOpt = PGOOptions("", "", "", PGOOptions::NoAction,
+                        PGOOptions::NoCSAction, true);
+
+  // Check to see if we want to generate a CS profile.
+  if (CodeGenOpts.hasProfileCSIRInstr()) {
+    assert(!CodeGenOpts.hasProfileCSIRUse() &&
+           "Cannot have both CSProfileUse pass and CSProfileGen pass at "
+           "the same time");
+    if (PGOOpt.hasValue()) {
+      assert(PGOOpt->Action != PGOOptions::IRInstr &&
+             PGOOpt->Action != PGOOptions::SampleUse &&
+             "Cannot run CSProfileGen pass with ProfileGen or SampleUse "
+             " pass");
+      PGOOpt->CSProfileGenFile = CodeGenOpts.InstrProfileOutput.empty()
+                                     ? DefaultProfileGenName
+                                     : CodeGenOpts.InstrProfileOutput;
+      PGOOpt->CSAction = PGOOptions::CSIRInstr;
+    } else
+      PGOOpt = PGOOptions("",
+                          CodeGenOpts.InstrProfileOutput.empty()
+                              ? DefaultProfileGenName
+                              : CodeGenOpts.InstrProfileOutput,
+                          "", PGOOptions::NoAction, PGOOptions::CSIRInstr,
+                          CodeGenOpts.DebugInfoForProfiling);
+  }
 
   PassBuilder PB(TM.get(), PGOOpt);
 
@@ -1302,6 +1345,16 @@ static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M,
   Conf.CGOptLevel = getCGOptLevel(CGOpts);
   initTargetOptions(Conf.Options, CGOpts, TOpts, LOpts, HeaderOpts);
   Conf.SampleProfile = std::move(SampleProfile);
+
+  // Context sensitive profile.
+  if (CGOpts.hasProfileCSIRInstr()) {
+    Conf.RunCSIRInstr = true;
+    Conf.CSIRProfile = std::move(CGOpts.InstrProfileOutput);
+  } else if (CGOpts.hasProfileCSIRUse()) {
+    Conf.RunCSIRInstr = false;
+    Conf.CSIRProfile = std::move(CGOpts.ProfileInstrumentUsePath);
+  }
+
   Conf.ProfileRemapping = std::move(ProfileRemapping);
   Conf.UseNewPM = CGOpts.ExperimentalNewPassManager;
   Conf.DebugPassManager = CGOpts.DebugPassManager;

diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 289d47d..93a8d90 100644 (file)
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -405,6 +405,8 @@ bool ToolChain::needsProfileRT(const ArgList &Args) {
   if (needsGCovInstrumentation(Args) ||
       Args.hasArg(options::OPT_fprofile_generate) ||
       Args.hasArg(options::OPT_fprofile_generate_EQ) ||
+      Args.hasArg(options::OPT_fcs_profile_generate) ||
+      Args.hasArg(options::OPT_fcs_profile_generate_EQ) ||
       Args.hasArg(options::OPT_fprofile_instr_generate) ||
       Args.hasArg(options::OPT_fprofile_instr_generate_EQ) ||
       Args.hasArg(options::OPT_fcreate_profile))

diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index ba2b850..987b0a7 100644 (file)
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -729,6 +729,13 @@ static void addPGOAndCoverageFlags(Compilation &C, const Driver &D,
       PGOGenerateArg->getOption().matches(options::OPT_fno_profile_generate))
     PGOGenerateArg = nullptr;
 
+  auto *CSPGOGenerateArg = Args.getLastArg(options::OPT_fcs_profile_generate,
+                                           options::OPT_fcs_profile_generate_EQ,
+                                           options::OPT_fno_profile_generate);
+  if (CSPGOGenerateArg &&
+      CSPGOGenerateArg->getOption().matches(options::OPT_fno_profile_generate))
+    CSPGOGenerateArg = nullptr;
+
   auto *ProfileGenerateArg = Args.getLastArg(
       options::OPT_fprofile_instr_generate,
       options::OPT_fprofile_instr_generate_EQ,
@@ -752,6 +759,10 @@ static void addPGOAndCoverageFlags(Compilation &C, const Driver &D,
     D.Diag(diag::err_drv_argument_not_allowed_with)
         << ProfileGenerateArg->getSpelling() << ProfileUseArg->getSpelling();
 
+  if (CSPGOGenerateArg && PGOGenerateArg)
+    D.Diag(diag::err_drv_argument_not_allowed_with)
+        << CSPGOGenerateArg->getSpelling() << PGOGenerateArg->getSpelling();
+
   if (ProfileGenerateArg) {
     if (ProfileGenerateArg->getOption().matches(
             options::OPT_fprofile_instr_generate_EQ))
@@ -761,11 +772,22 @@ static void addPGOAndCoverageFlags(Compilation &C, const Driver &D,
     CmdArgs.push_back("-fprofile-instrument=clang");
   }
 
+  Arg *PGOGenArg = nullptr;
   if (PGOGenerateArg) {
+    assert(!CSPGOGenerateArg);
+    PGOGenArg = PGOGenerateArg;
     CmdArgs.push_back("-fprofile-instrument=llvm");
-    if (PGOGenerateArg->getOption().matches(
-            options::OPT_fprofile_generate_EQ)) {
-      SmallString<128> Path(PGOGenerateArg->getValue());
+  }
+  if (CSPGOGenerateArg) {
+    assert(!PGOGenerateArg);
+    PGOGenArg = CSPGOGenerateArg;
+    CmdArgs.push_back("-fprofile-instrument=csllvm");
+  }
+  if (PGOGenArg) {
+    if (PGOGenArg->getOption().matches(
+            PGOGenerateArg ? options::OPT_fprofile_generate_EQ
+                           : options::OPT_fcs_profile_generate_EQ)) {
+      SmallString<128> Path(PGOGenArg->getValue());
       llvm::sys::path::append(Path, "default_%m.profraw");
       CmdArgs.push_back(
           Args.MakeArgString(Twine("-fprofile-instrument-path=") + Path));
@@ -4613,6 +4635,14 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   // Forward -f options with positive and negative forms; we translate
   // these by hand.
   if (Arg *A = getLastProfileSampleUseArg(Args)) {
+    auto *PGOArg = Args.getLastArg(
+        options::OPT_fprofile_generate, options::OPT_fprofile_generate_EQ,
+        options::OPT_fcs_profile_generate, options::OPT_fcs_profile_generate_EQ,
+        options::OPT_fprofile_use, options::OPT_fprofile_use_EQ);
+    if (PGOArg)
+      D.Diag(diag::err_drv_argument_not_allowed_with)
+          << "SampleUse with PGO options";
+
     StringRef fname = A->getValue();
     if (!llvm::sys::fs::exists(fname))
       D.Diag(diag::err_drv_no_such_file) << fname;

diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index 21d8742..a3d7a60 100644 (file)
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -443,6 +443,31 @@ void tools::AddGoldPlugin(const ToolChain &ToolChain, const ArgList &Args,
           Args.MakeArgString(Twine("-plugin-opt=sample-profile=") + FName));
   }
 
+  auto *CSPGOGenerateArg = Args.getLastArg(options::OPT_fcs_profile_generate,
+                                           options::OPT_fcs_profile_generate_EQ,
+                                           options::OPT_fno_profile_generate);
+  if (CSPGOGenerateArg &&
+      CSPGOGenerateArg->getOption().matches(options::OPT_fno_profile_generate))
+    CSPGOGenerateArg = nullptr;
+
+  auto *ProfileUseArg = getLastProfileUseArg(Args);
+
+  if (CSPGOGenerateArg) {
+    CmdArgs.push_back(Args.MakeArgString("-plugin-opt=cs-profile-generate"));
+    if (CSPGOGenerateArg->getOption().matches(
+            options::OPT_fcs_profile_generate_EQ)) {
+      SmallString<128> Path(CSPGOGenerateArg->getValue());
+      llvm::sys::path::append(Path, "default_%m.profraw");
+      CmdArgs.push_back(
+          Args.MakeArgString(Twine("-plugin-opt=cs-profile-path=") + Path));
+    } else
+      CmdArgs.push_back(
+          Args.MakeArgString("-plugin-opt=cs-profile-path=default_%m.profraw"));
+  } else if (ProfileUseArg) {
+    CmdArgs.push_back(Args.MakeArgString(Twine("-plugin-opt=cs-profile-path=") +
+                                         ProfileUseArg->getValue()));
+  }
+
   // Need this flag to turn on new pass manager via Gold plugin.
   if (Args.hasFlag(options::OPT_fexperimental_new_pass_manager,
                    options::OPT_fno_experimental_new_pass_manager,

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 4d061c6..1cd1cb1 100644 (file)
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -588,6 +588,7 @@ static void setPGOInstrumentor(CodeGenOptions &Opts, ArgList &Args,
                    .Case("none", CodeGenOptions::ProfileNone)
                    .Case("clang", CodeGenOptions::ProfileClangInstr)
                    .Case("llvm", CodeGenOptions::ProfileIRInstr)
+                   .Case("csllvm", CodeGenOptions::ProfileCSIRInstr)
                    .Default(~0U);
   if (I == ~0U) {
     Diags.Report(diag::err_drv_invalid_pgo_instrumentor) << A->getAsString(Args)
@@ -610,9 +611,12 @@ static void setPGOUseInstrumentor(CodeGenOptions &Opts,
   }
   std::unique_ptr<llvm::IndexedInstrProfReader> PGOReader =
     std::move(ReaderOrErr.get());
-  if (PGOReader->isIRLevelProfile())
-    Opts.setProfileUse(CodeGenOptions::ProfileIRInstr);
-  else
+  if (PGOReader->isIRLevelProfile()) {
+    if (PGOReader->hasCSIRLevelProfile())
+      Opts.setProfileUse(CodeGenOptions::ProfileCSIRInstr);
+    else
+      Opts.setProfileUse(CodeGenOptions::ProfileIRInstr);
+  } else
     Opts.setProfileUse(CodeGenOptions::ProfileClangInstr);
 }