OpenMPOpt Remarks Support

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D79359

diff --git a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
index dbd06a6..dd66c67 100644 (file)
--- a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
+++ b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
@@ -18,6 +18,7 @@
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/CallGraph.h"
 #include "llvm/Analysis/CallGraphSCCPass.h"
+#include "llvm/Analysis/OptimizationRemarkEmitter.h"
 #include "llvm/Frontend/OpenMP/OMPConstants.h"
 #include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
 #include "llvm/InitializePasses.h"
@@ -50,11 +51,14 @@ static constexpr auto TAG = "[" DEBUG_TYPE "]";
 namespace {
 struct OpenMPOpt {
 
+  using OptimizationRemarkGetter =
+      function_ref<OptimizationRemarkEmitter &(Function *)>;
+
   OpenMPOpt(SmallVectorImpl<Function *> &SCC,
             SmallPtrSetImpl<Function *> &ModuleSlice,
-            CallGraphUpdater &CGUpdater)
+            CallGraphUpdater &CGUpdater, OptimizationRemarkGetter OREGetter)
       : M(*(*SCC.begin())->getParent()), SCC(SCC), ModuleSlice(ModuleSlice),
-        OMPBuilder(M), CGUpdater(CGUpdater) {
+        OMPBuilder(M), CGUpdater(CGUpdater), OREGetter(OREGetter) {
     initializeTypes(M);
     initializeRuntimeFunctions();
     OMPBuilder.initialize();
@@ -178,6 +182,15 @@ private:
 
       LLVM_DEBUG(dbgs() << TAG << "Delete read-only parallel region in "
                         << CI->getCaller()->getName() << "\n");
+
+      auto Remark = [&](OptimizationRemark OR) {
+        return OR << "Parallel region in "
+                  << ore::NV("OpenMPParallelDelete", CI->getCaller()->getName())
+                  << " deleted";
+      };
+      emitRemark<OptimizationRemark>(CI, "OpenMPParallelRegionDeletion",
+                                     Remark);
+
       CGUpdater.removeCallSite(*CI);
       CI->eraseFromParent();
       Changed = true;
@@ -317,6 +330,15 @@ private:
         if (CallInst *CI = getCallIfRegularCall(*U, &RFI)) {
           if (!CanBeMoved(*CI))
             continue;
+
+          auto Remark = [&](OptimizationRemark OR) {
+            auto newLoc = &*F.getEntryBlock().getFirstInsertionPt();
+            return OR << "OpenMP runtime call "
+                      << ore::NV("OpenMPOptRuntime", RFI.Name) << " moved to "
+                      << ore::NV("OpenMPRuntimeMoves", newLoc->getDebugLoc());
+          };
+          emitRemark<OptimizationRemark>(CI, "OpenMPRuntimeCodeMotion", Remark);
+
           CI->moveBefore(&*F.getEntryBlock().getFirstInsertionPt());
           ReplVal = CI;
           break;
@@ -343,6 +365,13 @@ private:
       if (!CI || CI == ReplVal || &F != &Caller)
         return false;
       assert(CI->getCaller() == &F && "Unexpected call!");
+
+      auto Remark = [&](OptimizationRemark OR) {
+        return OR << "OpenMP runtime call "
+                  << ore::NV("OpenMPOptRuntime", RFI.Name) << " deduplicated";
+      };
+      emitRemark<OptimizationRemark>(CI, "OpenMPRuntimeDeduplicated", Remark);
+
       CGUpdater.removeCallSite(*CI);
       CI->replaceAllUsesWith(ReplVal);
       CI->eraseFromParent();
@@ -508,6 +537,29 @@ private:
     // TODO: We should attach the attributes defined in OMPKinds.def.
   }
 
+  /// Emit a remark generically
+  ///
+  /// This template function can be used to generically emit a remark. The
+  /// RemarkKind should be one of the following:
+  ///   - OptimizationRemark to indicate a successful optimization attempt
+  ///   - OptimizationRemarkMissed to report a failed optimization attempt
+  ///   - OptimizationRemarkAnalysis to provide additional information about an
+  ///     optimization attempt
+  ///
+  /// The remark is built using a callback function provided by the caller that
+  /// takes a RemarkKind as input and returns a RemarkKind.
+  template <typename RemarkKind,
+            typename RemarkCallBack = function_ref<RemarkKind(RemarkKind &&)>>
+  void emitRemark(Instruction *Inst, StringRef RemarkName,
+                  RemarkCallBack &&RemarkCB) {
+    Function *F = Inst->getParent()->getParent();
+    auto &ORE = OREGetter(F);
+
+    ORE.emit([&]() {
+      return RemarkCB(RemarkKind(DEBUG_TYPE, RemarkName, Inst)); 
+    });
+  }
+
   /// The underyling module.
   Module &M;
 
@@ -524,6 +576,9 @@ private:
   /// the second an optional replacement call.
   CallGraphUpdater &CGUpdater;
 
+  /// Callback to get an OptimizationRemarkEmitter from a Function *
+  OptimizationRemarkGetter OREGetter;
+
   /// Map from runtime function kind to the runtime function description.
   EnumeratedArray<RuntimeFunctionInfo, RuntimeFunction,
                   RuntimeFunction::OMPRTL___last>
@@ -550,10 +605,16 @@ PreservedAnalyses OpenMPOptPass::run(LazyCallGraph::SCC &C,
   if (SCC.empty())
     return PreservedAnalyses::all();
 
+  auto OREGetter = [&C, &CG, &AM](Function *F) -> OptimizationRemarkEmitter & {
+    FunctionAnalysisManager &FAM =
+        AM.getResult<FunctionAnalysisManagerCGSCCProxy>(C, CG).getManager();
+    return FAM.getResult<OptimizationRemarkEmitterAnalysis>(*F);
+  };
+
   CallGraphUpdater CGUpdater;
   CGUpdater.initialize(CG, C, AM, UR);
   // TODO: Compute the module slice we are allowed to look at.
-  OpenMPOpt OMPOpt(SCC, ModuleSlice, CGUpdater);
+  OpenMPOpt OMPOpt(SCC, ModuleSlice, CGUpdater, OREGetter);
   bool Changed = OMPOpt.run();
   (void)Changed;
   return PreservedAnalyses::all();
@@ -601,8 +662,17 @@ struct OpenMPOptLegacyPass : public CallGraphSCCPass {
     CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph();
     CGUpdater.initialize(CG, CGSCC);
 
+    // Maintain a map of functions to avoid rebuilding the ORE
+    DenseMap<Function *, std::unique_ptr<OptimizationRemarkEmitter>> OREMap;
+    auto OREGetter = [&OREMap](Function *F) -> OptimizationRemarkEmitter & {
+      std::unique_ptr<OptimizationRemarkEmitter> &ORE = OREMap[F];
+      if (!ORE)
+        ORE = std::make_unique<OptimizationRemarkEmitter>(F);
+      return *ORE;
+    };
+
     // TODO: Compute the module slice we are allowed to look at.
-    OpenMPOpt OMPOpt(SCC, ModuleSlice, CGUpdater);
+    OpenMPOpt OMPOpt(SCC, ModuleSlice, CGUpdater, OREGetter);
     return OMPOpt.run();
   }
 

diff --git a/llvm/test/Transforms/OpenMP/deduplication_remarks.ll b/llvm/test/Transforms/OpenMP/deduplication_remarks.ll
new file mode 100644 (file)
index 0000000..d04cc66
--- /dev/null
+++ b/llvm/test/Transforms/OpenMP/deduplication_remarks.ll
@@ -0,0 +1,64 @@
+; RUN: opt -openmpopt -pass-remarks=openmp-opt -disable-output < %s 2>&1 | FileCheck %s
+; RUN: opt -passes=openmpopt -pass-remarks=openmp-opt -disable-output < %s 2>&1 | FileCheck %s
+; ModuleID = 'deduplication_remarks.c'
+source_filename = "deduplication_remarks.c"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-linux-gnu"
+
+%struct.ident_t = type { i32, i32, i32, i32, i8* }
+
+@0 = private unnamed_addr global %struct.ident_t { i32 0, i32 34, i32 0, i32 0, i8* getelementptr inbounds ([23 x i8], [23 x i8]* @.str0, i32 0, i32 0) }, align 8
+@.str0 = private unnamed_addr constant [23 x i8] c";unknown;unknown;0;0;;\00", align 1
+
+; CHECK: remark: deduplication_remarks.c:9:10: OpenMP runtime call __kmpc_global_thread_num moved to deduplication_remarks.c:5:10
+; CHECK: remark: deduplication_remarks.c:7:10: OpenMP runtime call __kmpc_global_thread_num deduplicated
+; CHECK: remark: deduplication_remarks.c:5:10: OpenMP runtime call __kmpc_global_thread_num deduplicated
+define dso_local void @deduplicate() local_unnamed_addr !dbg !14 {
+  %1 = tail call i32 @__kmpc_global_thread_num(%struct.ident_t* nonnull @0), !dbg !21
+  call void @useI32(i32 %1), !dbg !23
+  %2 = tail call i32 @__kmpc_global_thread_num(%struct.ident_t* nonnull @0), !dbg !24
+  call void @useI32(i32 %2), !dbg !25
+  %3 = tail call i32 @__kmpc_global_thread_num(%struct.ident_t* nonnull @0), !dbg !26
+  call void @useI32(i32 %3), !dbg !27
+  ret void, !dbg !28
+}
+
+declare i32 @__kmpc_global_thread_num(%struct.ident_t*)
+
+declare !dbg !4 void @useI32(i32) local_unnamed_addr
+
+declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!8, !9, !10, !11, !12}
+!llvm.ident = !{!13}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: "deduplication_remarks.c", directory: "/tmp")
+!2 = !{}
+!3 = !{!4}
+!4 = !DISubprogram(name: "useI32", scope: !1, file: !1, line: 1, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
+!5 = !DISubroutineType(types: !6)
+!6 = !{null, !7}
+!7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!8 = !{i32 7, !"Dwarf Version", i32 4}
+!9 = !{i32 2, !"Debug Info Version", i32 3}
+!10 = !{i32 1, !"wchar_size", i32 4}
+!11 = !{i32 7, !"PIC Level", i32 2}
+!12 = !{i32 7, !"PIE Level", i32 2}
+!13 = !{!"clang version 10.0.0 "}
+!14 = distinct !DISubprogram(name: "deduplicate", scope: !1, file: !1, line: 4, type: !15, scopeLine: 4, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !17)
+!15 = !DISubroutineType(types: !16)
+!16 = !{null}
+!17 = !{!18, !19, !20}
+!18 = !DILocalVariable(name: "x", scope: !14, file: !1, line: 5, type: !7)
+!19 = !DILocalVariable(name: "y", scope: !14, file: !1, line: 7, type: !7)
+!20 = !DILocalVariable(name: "z", scope: !14, file: !1, line: 9, type: !7)
+!21 = !DILocation(line: 5, column: 10, scope: !14)
+!22 = !DILocation(line: 0, scope: !14)
+!23 = !DILocation(line: 6, column: 2, scope: !14)
+!24 = !DILocation(line: 7, column: 10, scope: !14)
+!25 = !DILocation(line: 8, column: 2, scope: !14)
+!26 = !DILocation(line: 9, column: 10, scope: !14)
+!27 = !DILocation(line: 10, column: 2, scope: !14)
+!28 = !DILocation(line: 13, column: 1, scope: !14)

diff --git a/llvm/test/Transforms/OpenMP/parallel_deletion_remarks.ll b/llvm/test/Transforms/OpenMP/parallel_deletion_remarks.ll
new file mode 100644 (file)
index 0000000..eea76bf
--- /dev/null
+++ b/llvm/test/Transforms/OpenMP/parallel_deletion_remarks.ll
@@ -0,0 +1,126 @@
+; RUN: opt -S -pass-remarks=openmp-opt -attributor -openmpopt -disable-output < %s 2>&1 | FileCheck %s
+; RUN: opt -S -pass-remarks=openmp-opt -passes='attributor,cgscc(openmpopt)' -disable-output < %s 2>&1 | FileCheck %s
+; ModuleID = 'parallel_deletion_remarks.ll'
+source_filename = "parallel_deletion_remarks.c"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-linux-gnu"
+
+%struct.ident_t = type { i32, i32, i32, i32, i8* }
+
+@.str = private unnamed_addr constant [23 x i8] c";unknown;unknown;0;0;;\00", align 1
+@0 = private unnamed_addr constant %struct.ident_t { i32 0, i32 2, i32 0, i32 0, i8* getelementptr inbounds ([23 x i8], [23 x i8]* @.str, i32 0, i32 0) }, align 8
+
+; void delete_parallel(void) {
+; #pragma omp parallel
+;      { unknown_willreturn(); }
+; #pragma omp parallel
+;      { readonly_willreturn(); }
+; #pragma omp parallel
+;      { readnone_willreturn(); }
+; #pragma omp parallel
+;      {}
+; }
+;
+; This will delete all but the first parallel region
+
+; CHECK: remark: parallel_deletion_remarks.c:14:1: Parallel region in delete_parallel deleted
+; CHECK: remark: parallel_deletion_remarks.c:12:1: Parallel region in delete_parallel deleted
+; CHECK: remark: parallel_deletion_remarks.c:10:1: Parallel region in delete_parallel deleted
+define dso_local void @delete_parallel() local_unnamed_addr !dbg !15 {
+  call void (%struct.ident_t*, i32, void (i32*, i32*, ...)*, ...) @__kmpc_fork_call(%struct.ident_t* nonnull @0, i32 0, void (i32*, i32*, ...)* bitcast (void (i32*, i32*)* @.omp_outlined. to void (i32*, i32*, ...)*)), !dbg !18
+  call void (%struct.ident_t*, i32, void (i32*, i32*, ...)*, ...) @__kmpc_fork_call(%struct.ident_t* nonnull @0, i32 0, void (i32*, i32*, ...)* bitcast (void (i32*, i32*)* @.omp_outlined..2 to void (i32*, i32*, ...)*)), !dbg !19
+  call void (%struct.ident_t*, i32, void (i32*, i32*, ...)*, ...) @__kmpc_fork_call(%struct.ident_t* nonnull @0, i32 0, void (i32*, i32*, ...)* bitcast (void (i32*, i32*)* @.omp_outlined..4 to void (i32*, i32*, ...)*)), !dbg !20
+  call void (%struct.ident_t*, i32, void (i32*, i32*, ...)*, ...) @__kmpc_fork_call(%struct.ident_t* nonnull @0, i32 0, void (i32*, i32*, ...)* bitcast (void (i32*, i32*)* @.omp_outlined..6 to void (i32*, i32*, ...)*)), !dbg !21
+  ret void, !dbg !22
+}
+
+declare !callback !23 void @__kmpc_fork_call(%struct.ident_t*, i32, void (i32*, i32*, ...)*, ...) local_unnamed_addr
+
+; Function Attrs: willreturn
+declare !dbg !4 void @unknown_willreturn(...) #0
+
+; Function Attrs: readonly willreturn
+declare !dbg !7 void @readonly_willreturn(...) #1
+
+; Function Attrs: readnone willreturn
+declare !dbg !8 void @readnone_willreturn(...) #2
+
+define internal void @.omp_outlined.(i32* noalias nocapture readnone %0, i32* noalias nocapture readnone %1) !dbg !25 {
+  call void (...) @unknown_willreturn(), !dbg !36
+  ret void, !dbg !36
+}
+
+define internal void @.omp_outlined..2(i32* noalias nocapture readnone %0, i32* noalias nocapture readnone %1) !dbg !37 {
+  call void (...) @readonly_willreturn(), !dbg !41
+  ret void, !dbg !41
+}
+
+define internal void @.omp_outlined..4(i32* noalias nocapture readnone %0, i32* noalias nocapture readnone %1) !dbg !42 {
+  call void (...) @readnone_willreturn(), !dbg !46
+  ret void, !dbg !46
+}
+
+define internal void @.omp_outlined..6(i32* noalias nocapture %0, i32* noalias nocapture %1) !dbg !47 {
+  ret void, !dbg !51
+}
+
+attributes #0 = { willreturn }
+attributes #1 = { readonly willreturn }
+attributes #2 = { readnone willreturn }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!9, !10, !11, !12, !13}
+!llvm.ident = !{!14}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: "parallel_deletion_remarks.c", directory: "/tmp")
+!2 = !{}
+!3 = !{!4, !7, !8}
+!4 = !DISubprogram(name: "unknown_willreturn", scope: !1, file: !1, line: 3, type: !5, spFlags: DISPFlagOptimized, retainedNodes: !2)
+!5 = !DISubroutineType(types: !6)
+!6 = !{null, null}
+!7 = !DISubprogram(name: "readonly_willreturn", scope: !1, file: !1, line: 4, type: !5, spFlags: DISPFlagOptimized, retainedNodes: !2)
+!8 = !DISubprogram(name: "readnone_willreturn", scope: !1, file: !1, line: 5, type: !5, spFlags: DISPFlagOptimized, retainedNodes: !2)
+!9 = !{i32 7, !"Dwarf Version", i32 4}
+!10 = !{i32 2, !"Debug Info Version", i32 3}
+!11 = !{i32 1, !"wchar_size", i32 4}
+!12 = !{i32 7, !"PIC Level", i32 2}
+!13 = !{i32 7, !"PIE Level", i32 2}
+!14 = !{!"clang version 10.0.0 "}
+!15 = distinct !DISubprogram(name: "delete_parallel", scope: !1, file: !1, line: 7, type: !16, scopeLine: 7, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2)
+!16 = !DISubroutineType(types: !17)
+!17 = !{null}
+!18 = !DILocation(line: 8, column: 1, scope: !15)
+!19 = !DILocation(line: 10, column: 1, scope: !15)
+!20 = !DILocation(line: 12, column: 1, scope: !15)
+!21 = !DILocation(line: 14, column: 1, scope: !15)
+!22 = !DILocation(line: 16, column: 1, scope: !15)
+!23 = !{!24}
+!24 = !{i64 2, i64 -1, i64 -1, i1 true}
+!25 = distinct !DISubprogram(name: ".omp_outlined.", scope: !1, file: !1, line: 9, type: !26, scopeLine: 9, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !33)
+!26 = !DISubroutineType(types: !27)
+!27 = !{null, !28, !28}
+!28 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !29)
+!29 = !DIDerivedType(tag: DW_TAG_restrict_type, baseType: !30)
+!30 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !31, size: 64)
+!31 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !32)
+!32 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!33 = !{!34, !35}
+!34 = !DILocalVariable(name: ".global_tid.", arg: 1, scope: !25, type: !28, flags: DIFlagArtificial)
+!35 = !DILocalVariable(name: ".bound_tid.", arg: 2, scope: !25, type: !28, flags: DIFlagArtificial)
+!36 = !DILocation(line: 9, column: 2, scope: !25)
+!37 = distinct !DISubprogram(name: ".omp_outlined..2", scope: !1, file: !1, line: 11, type: !26, scopeLine: 11, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !38)
+!38 = !{!39, !40}
+!39 = !DILocalVariable(name: ".global_tid.", arg: 1, scope: !37, type: !28, flags: DIFlagArtificial)
+!40 = !DILocalVariable(name: ".bound_tid.", arg: 2, scope: !37, type: !28, flags: DIFlagArtificial)
+!41 = !DILocation(line: 11, column: 2, scope: !37)
+!42 = distinct !DISubprogram(name: ".omp_outlined..4", scope: !1, file: !1, line: 13, type: !26, scopeLine: 13, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !43)
+!43 = !{!44, !45}
+!44 = !DILocalVariable(name: ".global_tid.", arg: 1, scope: !42, type: !28, flags: DIFlagArtificial)
+!45 = !DILocalVariable(name: ".bound_tid.", arg: 2, scope: !42, type: !28, flags: DIFlagArtificial)
+!46 = !DILocation(line: 13, column: 2, scope: !42)
+!47 = distinct !DISubprogram(name: ".omp_outlined..6", scope: !1, file: !1, line: 15, type: !26, scopeLine: 15, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !48)
+!48 = !{!49, !50}
+!49 = !DILocalVariable(name: ".global_tid.", arg: 1, scope: !47, type: !28, flags: DIFlagArtificial)
+!50 = !DILocalVariable(name: ".bound_tid.", arg: 2, scope: !47, type: !28, flags: DIFlagArtificial)
+!51 = !DILocation(line: 15, column: 2, scope: !47)