1 //=== RISCVPreLegalizerCombiner.cpp ---------------------------------------===//
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 pass does combining of machine instructions at the generic MI level,
10 // before the legalizer.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "RISCVSubtarget.h"
15 #include "llvm/CodeGen/GlobalISel/CSEInfo.h"
16 #include "llvm/CodeGen/GlobalISel/Combiner.h"
17 #include "llvm/CodeGen/GlobalISel/CombinerHelper.h"
18 #include "llvm/CodeGen/GlobalISel/CombinerInfo.h"
19 #include "llvm/CodeGen/GlobalISel/GIMatchTableExecutorImpl.h"
20 #include "llvm/CodeGen/GlobalISel/GISelKnownBits.h"
21 #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
22 #include "llvm/CodeGen/MachineDominators.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineFunctionPass.h"
25 #include "llvm/CodeGen/MachineRegisterInfo.h"
26 #include "llvm/CodeGen/TargetPassConfig.h"
27
28 #define GET_GICOMBINER_DEPS
29 #include "RISCVGenPreLegalizeGICombiner.inc"
30 #undef GET_GICOMBINER_DEPS
31
32 #define DEBUG_TYPE "riscv-prelegalizer-combiner"
33
34 using namespace llvm;
35
36 namespace {
37
38 #define GET_GICOMBINER_TYPES
39 #include "RISCVGenPreLegalizeGICombiner.inc"
40 #undef GET_GICOMBINER_TYPES
41
42 class RISCVPreLegalizerCombinerImpl : public Combiner {
43 protected:
44 // TODO: Make CombinerHelper methods const.
45 mutable CombinerHelper Helper;
46 const RISCVPreLegalizerCombinerImplRuleConfig &RuleConfig;
47 const RISCVSubtarget &STI;
48
49 public:
50 RISCVPreLegalizerCombinerImpl(
51 MachineFunction &MF, CombinerInfo &CInfo, const TargetPassConfig *TPC,
52 GISelKnownBits &KB, GISelCSEInfo *CSEInfo,
53 const RISCVPreLegalizerCombinerImplRuleConfig &RuleConfig,
54 const RISCVSubtarget &STI, MachineDominatorTree *MDT,
55 const LegalizerInfo *LI);
56
getName()57 static const char *getName() { return "RISCV00PreLegalizerCombiner"; }
58
59 bool tryCombineAll(MachineInstr &I) const override;
60
61 private:
62 #define GET_GICOMBINER_CLASS_MEMBERS
63 #include "RISCVGenPreLegalizeGICombiner.inc"
64 #undef GET_GICOMBINER_CLASS_MEMBERS
65 };
66
67 #define GET_GICOMBINER_IMPL
68 #include "RISCVGenPreLegalizeGICombiner.inc"
69 #undef GET_GICOMBINER_IMPL
70
RISCVPreLegalizerCombinerImpl(MachineFunction & MF,CombinerInfo & CInfo,const TargetPassConfig * TPC,GISelKnownBits & KB,GISelCSEInfo * CSEInfo,const RISCVPreLegalizerCombinerImplRuleConfig & RuleConfig,const RISCVSubtarget & STI,MachineDominatorTree * MDT,const LegalizerInfo * LI)71 RISCVPreLegalizerCombinerImpl::RISCVPreLegalizerCombinerImpl(
72 MachineFunction &MF, CombinerInfo &CInfo, const TargetPassConfig *TPC,
73 GISelKnownBits &KB, GISelCSEInfo *CSEInfo,
74 const RISCVPreLegalizerCombinerImplRuleConfig &RuleConfig,
75 const RISCVSubtarget &STI, MachineDominatorTree *MDT,
76 const LegalizerInfo *LI)
77 : Combiner(MF, CInfo, TPC, &KB, CSEInfo),
78 Helper(Observer, B, /*IsPreLegalize*/ true, &KB, MDT, LI),
79 RuleConfig(RuleConfig), STI(STI),
80 #define GET_GICOMBINER_CONSTRUCTOR_INITS
81 #include "RISCVGenPreLegalizeGICombiner.inc"
82 #undef GET_GICOMBINER_CONSTRUCTOR_INITS
83 {
84 }
85
86 // Pass boilerplate
87 // ================
88
89 class RISCVPreLegalizerCombiner : public MachineFunctionPass {
90 public:
91 static char ID;
92
93 RISCVPreLegalizerCombiner();
94
getPassName() const95 StringRef getPassName() const override { return "RISCVPreLegalizerCombiner"; }
96
97 bool runOnMachineFunction(MachineFunction &MF) override;
98
99 void getAnalysisUsage(AnalysisUsage &AU) const override;
100
101 private:
102 RISCVPreLegalizerCombinerImplRuleConfig RuleConfig;
103 };
104 } // end anonymous namespace
105
getAnalysisUsage(AnalysisUsage & AU) const106 void RISCVPreLegalizerCombiner::getAnalysisUsage(AnalysisUsage &AU) const {
107 AU.addRequired<TargetPassConfig>();
108 AU.setPreservesCFG();
109 getSelectionDAGFallbackAnalysisUsage(AU);
110 AU.addRequired<GISelKnownBitsAnalysis>();
111 AU.addPreserved<GISelKnownBitsAnalysis>();
112 AU.addRequired<MachineDominatorTreeWrapperPass>();
113 AU.addPreserved<MachineDominatorTreeWrapperPass>();
114 AU.addRequired<GISelCSEAnalysisWrapperPass>();
115 AU.addPreserved<GISelCSEAnalysisWrapperPass>();
116 MachineFunctionPass::getAnalysisUsage(AU);
117 }
118
RISCVPreLegalizerCombiner()119 RISCVPreLegalizerCombiner::RISCVPreLegalizerCombiner()
120 : MachineFunctionPass(ID) {
121 initializeRISCVPreLegalizerCombinerPass(*PassRegistry::getPassRegistry());
122
123 if (!RuleConfig.parseCommandLineOption())
124 report_fatal_error("Invalid rule identifier");
125 }
126
runOnMachineFunction(MachineFunction & MF)127 bool RISCVPreLegalizerCombiner::runOnMachineFunction(MachineFunction &MF) {
128 if (MF.getProperties().hasProperty(
129 MachineFunctionProperties::Property::FailedISel))
130 return false;
131 auto &TPC = getAnalysis<TargetPassConfig>();
132
133 // Enable CSE.
134 GISelCSEAnalysisWrapper &Wrapper =
135 getAnalysis<GISelCSEAnalysisWrapperPass>().getCSEWrapper();
136 auto *CSEInfo = &Wrapper.get(TPC.getCSEConfig());
137
138 const RISCVSubtarget &ST = MF.getSubtarget<RISCVSubtarget>();
139 const auto *LI = ST.getLegalizerInfo();
140
141 const Function &F = MF.getFunction();
142 bool EnableOpt =
143 MF.getTarget().getOptLevel() != CodeGenOptLevel::None && !skipFunction(F);
144 GISelKnownBits *KB = &getAnalysis<GISelKnownBitsAnalysis>().get(MF);
145 MachineDominatorTree *MDT =
146 &getAnalysis<MachineDominatorTreeWrapperPass>().getDomTree();
147 CombinerInfo CInfo(/*AllowIllegalOps*/ true, /*ShouldLegalizeIllegal*/ false,
148 /*LegalizerInfo*/ nullptr, EnableOpt, F.hasOptSize(),
149 F.hasMinSize());
150 RISCVPreLegalizerCombinerImpl Impl(MF, CInfo, &TPC, *KB, CSEInfo, RuleConfig,
151 ST, MDT, LI);
152 return Impl.combineMachineInstrs();
153 }
154
155 char RISCVPreLegalizerCombiner::ID = 0;
156 INITIALIZE_PASS_BEGIN(RISCVPreLegalizerCombiner, DEBUG_TYPE,
157 "Combine RISC-V machine instrs before legalization", false,
158 false)
159 INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
160 INITIALIZE_PASS_DEPENDENCY(GISelKnownBitsAnalysis)
161 INITIALIZE_PASS_DEPENDENCY(GISelCSEAnalysisWrapperPass)
162 INITIALIZE_PASS_END(RISCVPreLegalizerCombiner, DEBUG_TYPE,
163 "Combine RISC-V machine instrs before legalization", false,
164 false)
165
166 namespace llvm {
createRISCVPreLegalizerCombiner()167 FunctionPass *createRISCVPreLegalizerCombiner() {
168 return new RISCVPreLegalizerCombiner();
169 }
170 } // end namespace llvm
171