1//=== ValueProfilePlugins.inc - set of plugins used by ValueProfileCollector =//
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// This file contains a set of plugin classes used in ValueProfileCollectorImpl.
10// Each plugin is responsible for collecting Value Profiling candidates for a
11// particular optimization.
12// Each plugin must satisfy the interface described in ValueProfileCollector.cpp
13//
14//===----------------------------------------------------------------------===//
15
16#include "ValueProfileCollector.h"
17#include "llvm/Analysis/IndirectCallVisitor.h"
18#include "llvm/Analysis/TargetLibraryInfo.h"
19#include "llvm/IR/InstVisitor.h"
20
21using namespace llvm;
22using CandidateInfo = ValueProfileCollector::CandidateInfo;
23
24extern cl::opt<bool> MemOPOptMemcmpBcmp;
25
26///--------------------------- MemIntrinsicPlugin ------------------------------
27class MemIntrinsicPlugin : public InstVisitor<MemIntrinsicPlugin> {
28 Function &F;
29 TargetLibraryInfo &TLI;
30 std::vector<CandidateInfo> *Candidates;
31
32public:
33 static constexpr InstrProfValueKind Kind = IPVK_MemOPSize;
34
35 MemIntrinsicPlugin(Function &Fn, TargetLibraryInfo &TLI)
36 : F(Fn), TLI(TLI), Candidates(nullptr) {}
37
38 void run(std::vector<CandidateInfo> &Cs) {
39 Candidates = &Cs;
40 visit(F);
41 Candidates = nullptr;
42 }
43 void visitMemIntrinsic(MemIntrinsic &MI) {
44 Value *Length = MI.getLength();
45 // Not instrument constant length calls.
46 if (isa<ConstantInt>(Val: Length))
47 return;
48
49 Instruction *InsertPt = &MI;
50 Instruction *AnnotatedInst = &MI;
51 Candidates->emplace_back(args: CandidateInfo{.V: Length, .InsertPt: InsertPt, .AnnotatedInst: AnnotatedInst});
52 }
53 void visitCallInst(CallInst &CI) {
54 if (!MemOPOptMemcmpBcmp)
55 return;
56 auto *F = CI.getCalledFunction();
57 if (!F)
58 return;
59 LibFunc Func;
60 if (TLI.getLibFunc(CB: CI, F&: Func) &&
61 (Func == LibFunc_memcmp || Func == LibFunc_bcmp)) {
62 Value *Length = CI.getArgOperand(i: 2);
63 // Not instrument constant length calls.
64 if (isa<ConstantInt>(Val: Length))
65 return;
66 Instruction *InsertPt = &CI;
67 Instruction *AnnotatedInst = &CI;
68 Candidates->emplace_back(args: CandidateInfo{.V: Length, .InsertPt: InsertPt, .AnnotatedInst: AnnotatedInst});
69 }
70 }
71};
72
73///------------------------ IndirectCallPromotionPlugin ------------------------
74class IndirectCallPromotionPlugin {
75 Function &F;
76
77public:
78 static constexpr InstrProfValueKind Kind = IPVK_IndirectCallTarget;
79
80 IndirectCallPromotionPlugin(Function &Fn, TargetLibraryInfo &TLI) : F(Fn) {}
81
82 void run(std::vector<CandidateInfo> &Candidates) {
83 std::vector<CallBase *> Result = findIndirectCalls(F);
84 for (Instruction *I : Result) {
85 Value *Callee = cast<CallBase>(Val: I)->getCalledOperand();
86 Instruction *InsertPt = I;
87 Instruction *AnnotatedInst = I;
88 Candidates.emplace_back(args: CandidateInfo{.V: Callee, .InsertPt: InsertPt, .AnnotatedInst: AnnotatedInst});
89 }
90 }
91};
92
93///--------------------- VirtualTableValueProfilingPlugin --------------------
94class VTableProfilingPlugin {
95 Function &F;
96
97public:
98 static constexpr InstrProfValueKind Kind = IPVK_VTableTarget;
99
100 VTableProfilingPlugin(Function &Fn, TargetLibraryInfo &TLI) : F(Fn) {}
101
102 void run(std::vector<CandidateInfo> &Candidates) {
103 std::vector<Instruction *> Result = findVTableAddrs(F);
104 for (Instruction *I : Result) {
105 Instruction *InsertPt = I->getNextNonDebugInstruction();
106 // When finding an insertion point, keep PHI and EH pad instructions
107 // before vp intrinsics. This is similar to
108 // `BasicBlock::getFirstInsertionPt`.
109 while (InsertPt && (dyn_cast<PHINode>(Val: InsertPt) || InsertPt->isEHPad()))
110 InsertPt = InsertPt->getNextNonDebugInstruction();
111 // Skip instrumentating the value if InsertPt is the last instruction.
112 // FIXME: Set InsertPt to the end of basic block to instrument the value
113 // if InsertPt is the last instruction.
114 if (InsertPt == nullptr)
115 continue;
116
117 Instruction *AnnotatedInst = I;
118 Candidates.emplace_back(args: CandidateInfo{.V: I, .InsertPt: InsertPt, .AnnotatedInst: AnnotatedInst});
119 }
120 }
121};
122
123///----------------------- Registration of the plugins -------------------------
124/// For now, registering a plugin with the ValueProfileCollector is done by
125/// adding the plugin type to the VP_PLUGIN_LIST macro.
126#define VP_PLUGIN_LIST \
127 MemIntrinsicPlugin, IndirectCallPromotionPlugin, VTableProfilingPlugin
128