1 //===-- AnnotationRemarks.cpp - Generate remarks for annotated instrs. ----===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Generate remarks for instructions marked with !annotation.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "llvm/Transforms/Scalar/AnnotationRemarks.h"
14 #include "llvm/ADT/MapVector.h"
15 #include "llvm/Analysis/OptimizationRemarkEmitter.h"
16 #include "llvm/Analysis/TargetLibraryInfo.h"
17 #include "llvm/IR/Function.h"
18 #include "llvm/IR/InstIterator.h"
19 #include "llvm/InitializePasses.h"
20 #include "llvm/Pass.h"
21 #include "llvm/Transforms/Scalar.h"
22 #include "llvm/Transforms/Utils/MemoryOpRemark.h"
23
24 using namespace llvm;
25 using namespace llvm::ore;
26
27 #define DEBUG_TYPE "annotation-remarks"
28 #define REMARK_PASS DEBUG_TYPE
29
tryEmitAutoInitRemark(ArrayRef<Instruction * > Instructions,OptimizationRemarkEmitter & ORE,const TargetLibraryInfo & TLI)30 static void tryEmitAutoInitRemark(ArrayRef<Instruction *> Instructions,
31 OptimizationRemarkEmitter &ORE,
32 const TargetLibraryInfo &TLI) {
33 // For every auto-init annotation generate a separate remark.
34 for (Instruction *I : Instructions) {
35 if (!AutoInitRemark::canHandle(I))
36 continue;
37
38 Function &F = *I->getParent()->getParent();
39 const DataLayout &DL = F.getParent()->getDataLayout();
40 AutoInitRemark Remark(ORE, REMARK_PASS, DL, TLI);
41 Remark.visit(I);
42 }
43 }
44
runImpl(Function & F,const TargetLibraryInfo & TLI)45 static void runImpl(Function &F, const TargetLibraryInfo &TLI) {
46 if (!OptimizationRemarkEmitter::allowExtraAnalysis(F, REMARK_PASS))
47 return;
48
49 // Track all annotated instructions aggregated based on their debug location.
50 DenseMap<MDNode *, SmallVector<Instruction *, 4>> DebugLoc2Annotated;
51
52 OptimizationRemarkEmitter ORE(&F);
53 // First, generate a summary of the annotated instructions.
54 MapVector<StringRef, unsigned> Mapping;
55 for (Instruction &I : instructions(F)) {
56 if (!I.hasMetadata(LLVMContext::MD_annotation))
57 continue;
58 auto Iter = DebugLoc2Annotated.insert({I.getDebugLoc().getAsMDNode(), {}});
59 Iter.first->second.push_back(&I);
60
61 for (const MDOperand &Op :
62 I.getMetadata(LLVMContext::MD_annotation)->operands()) {
63 auto Iter = Mapping.insert({cast<MDString>(Op.get())->getString(), 0});
64 Iter.first->second++;
65 }
66 }
67
68 for (const auto &KV : Mapping)
69 ORE.emit(OptimizationRemarkAnalysis(REMARK_PASS, "AnnotationSummary",
70 F.getSubprogram(), &F.front())
71 << "Annotated " << NV("count", KV.second) << " instructions with "
72 << NV("type", KV.first));
73
74 // For each debug location, look for all the instructions with annotations and
75 // generate more detailed remarks to be displayed at that location.
76 for (auto &KV : DebugLoc2Annotated) {
77 // Don't generate remarks with no debug location.
78 if (!KV.first)
79 continue;
80
81 tryEmitAutoInitRemark(KV.second, ORE, TLI);
82 }
83 }
84
85 namespace {
86
87 struct AnnotationRemarksLegacy : public FunctionPass {
88 static char ID;
89
AnnotationRemarksLegacy__anon074bf4f30111::AnnotationRemarksLegacy90 AnnotationRemarksLegacy() : FunctionPass(ID) {
91 initializeAnnotationRemarksLegacyPass(*PassRegistry::getPassRegistry());
92 }
93
runOnFunction__anon074bf4f30111::AnnotationRemarksLegacy94 bool runOnFunction(Function &F) override {
95 const TargetLibraryInfo &TLI =
96 getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(F);
97 runImpl(F, TLI);
98 return false;
99 }
100
getAnalysisUsage__anon074bf4f30111::AnnotationRemarksLegacy101 void getAnalysisUsage(AnalysisUsage &AU) const override {
102 AU.setPreservesAll();
103 AU.addRequired<TargetLibraryInfoWrapperPass>();
104 }
105 };
106
107 } // end anonymous namespace
108
109 char AnnotationRemarksLegacy::ID = 0;
110
111 INITIALIZE_PASS_BEGIN(AnnotationRemarksLegacy, "annotation-remarks",
112 "Annotation Remarks", false, false)
INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)113 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
114 INITIALIZE_PASS_END(AnnotationRemarksLegacy, "annotation-remarks",
115 "Annotation Remarks", false, false)
116
117 FunctionPass *llvm::createAnnotationRemarksLegacyPass() {
118 return new AnnotationRemarksLegacy();
119 }
120
run(Function & F,FunctionAnalysisManager & AM)121 PreservedAnalyses AnnotationRemarksPass::run(Function &F,
122 FunctionAnalysisManager &AM) {
123 auto &TLI = AM.getResult<TargetLibraryAnalysis>(F);
124 runImpl(F, TLI);
125 return PreservedAnalyses::all();
126 }
127