[ThinLTO] Support opt remarks options with distributed ThinLTO backends

Summary:
Passes down the necessary code ge options to the LTO Config to enable
-fdiagnostics-show-hotness and -fsave-optimization-record in the ThinLTO
backend for a distributed build.

Also, remove warning about not having PGO when the input is IR.

Reviewers: pcc

Subscribers: mehdi_amini, inglorion, eraman, cfe-commits

Differential Revision: https://reviews.llvm.org/D46464

llvm-svn: 331592

clang/lib/CodeGen/BackendUtil.cpp

@@ -1136,6 +1136,8 @@ static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M,
   Conf.SampleProfile = std::move(SampleProfile);
   Conf.UseNewPM = CGOpts.ExperimentalNewPassManager;
   Conf.DebugPassManager = CGOpts.DebugPassManager;
+  Conf.RemarksWithHotness = CGOpts.DiagnosticsWithHotness;
+  Conf.RemarksFilename = CGOpts.OptRecordFile;
   switch (Action) {
   case Backend_EmitNothing:
     Conf.PreCodeGenModuleHook = [](size_t Task, const Module &Mod) {
@@ -1159,7 +1161,7 @@ static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M,
     break;
   }
   if (Error E = thinBackend(
-          Conf, 0, AddStream, *M, *CombinedIndex, ImportList,
+          Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
           ModuleToDefinedGVSummaries[M->getModuleIdentifier()], ModuleMap)) {
     handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
       errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';

clang/lib/Frontend/CompilerInvocation.cpp

@@ -1075,7 +1075,9 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   bool UsingProfile = UsingSampleProfile ||
       (Opts.getProfileUse() != CodeGenOptions::ProfileNone);
 
-  if (Opts.DiagnosticsWithHotness && !UsingProfile)
+  if (Opts.DiagnosticsWithHotness && !UsingProfile &&
+      // An IR file will contain PGO as metadata
+      IK.getLanguage() != InputKind::LLVM_IR)
     Diags.Report(diag::warn_drv_diagnostics_hotness_requires_pgo)
         << "-fdiagnostics-show-hotness";
 

clang/test/CodeGen/thinlto-diagnostic-handler-remarks-with-hotness.ll

@@ -0,0 +1,47 @@
+; Test to ensure -fdiagnostics-show-hotness and -fsave-optimization-record
+; work when invoking the ThinLTO backend path.
+; RUN: opt -module-summary -o %t.o %s
+; RUN: llvm-lto -thinlto -o %t %t.o
+
+; First try with pass remarks to stderr
+; RUN: %clang -O2 -x ir %t.o -fthinlto-index=%t.thinlto.bc -mllvm -pass-remarks=inline -fdiagnostics-show-hotness -o %t2.o -c 2>&1 | FileCheck %s
+
+; CHECK: tinkywinky inlined into main with cost=0 (threshold=337) (hotness: 300)
+
+; Next try YAML pass remarks file
+; RUN: rm -f %t2.opt.yaml
+; RUN: %clang -O2 -x ir %t.o -fthinlto-index=%t.thinlto.bc -fsave-optimization-record -fdiagnostics-show-hotness -o %t2.o -c
+; RUN: cat %t2.opt.yaml | FileCheck %s -check-prefix=YAML
+
+; YAML: --- !Passed
+; YAML-NEXT: Pass:            inline
+; YAML-NEXT: Name:            Inlined
+; YAML-NEXT: Function:        main
+; YAML-NEXT: Hotness:         300
+; YAML-NEXT: Args:
+; YAML-NEXT:   - Callee:          tinkywinky
+; YAML-NEXT:   - String:          ' inlined into '
+; YAML-NEXT:   - Caller:          main
+; YAML-NEXT:   - String:          ' with cost='
+; YAML-NEXT:   - Cost:            '0'
+; YAML-NEXT:   - String:          ' (threshold='
+; YAML-NEXT:   - Threshold:       '337'
+; YAML-NEXT:   - String:          ')'
+; YAML-NEXT: ...
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-scei-ps4"
+
+declare i32 @patatino()
+
+define i32 @tinkywinky() {
+  %a = call i32 @patatino()
+  ret i32 %a
+}
+
+define i32 @main() !prof !0 {
+  %i = call i32 @tinkywinky()
+  ret i32 %i
+}
+
+!0 = !{!"function_entry_count", i64 300}

clang/test/CodeGen/thinlto_backend.ll

@@ -29,13 +29,13 @@
 
 ; Ensure f2 was imported. Check for all 3 flavors of -save-temps[=cwd|obj].
 ; RUN: %clang -target x86_64-unknown-linux-gnu -O2 -o %t3.o -x ir %t1.o -c -fthinlto-index=%t.thinlto.bc -save-temps=obj
-; RUN: llvm-dis %t1.s.0.3.import.bc -o - | FileCheck --check-prefix=CHECK-IMPORT %s
+; RUN: llvm-dis %t1.s.3.import.bc -o - | FileCheck --check-prefix=CHECK-IMPORT %s
 ; RUN: mkdir -p %T/dir1
 ; RUN: (cd %T/dir1 && %clang -target x86_64-unknown-linux-gnu -O2 -o %t3.o -x ir %t1.o -c -fthinlto-index=%t.thinlto.bc -save-temps=cwd)
-; RUN: llvm-dis %T/dir1/*1.s.0.3.import.bc -o - | FileCheck --check-prefix=CHECK-IMPORT %s
+; RUN: llvm-dis %T/dir1/*1.s.3.import.bc -o - | FileCheck --check-prefix=CHECK-IMPORT %s
 ; RUN: mkdir -p %T/dir2
 ; RUN: (cd %T/dir2 && %clang -target x86_64-unknown-linux-gnu -O2 -o %t3.o -x ir %t1.o -c -fthinlto-index=%t.thinlto.bc -save-temps)
-; RUN: llvm-dis %T/dir2/*1.s.0.3.import.bc -o - | FileCheck --check-prefix=CHECK-IMPORT %s
+; RUN: llvm-dis %T/dir2/*1.s.3.import.bc -o - | FileCheck --check-prefix=CHECK-IMPORT %s
 ; CHECK-IMPORT: define available_externally void @f2()
 ; RUN: llvm-nm %t3.o | FileCheck --check-prefix=CHECK-OBJ %s
 ; CHECK-OBJ: T f1