1 //=== lib/CodeGen/GlobalISel/MipsPreLegalizerCombiner.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 "MipsTargetMachine.h"
15 #include "llvm/CodeGen/GlobalISel/Combiner.h"
16 #include "llvm/CodeGen/GlobalISel/CombinerHelper.h"
17 #include "llvm/CodeGen/GlobalISel/CombinerInfo.h"
18 #include "llvm/CodeGen/GlobalISel/MIPatternMatch.h"
19 #include "llvm/CodeGen/TargetPassConfig.h"
20 #include "llvm/InitializePasses.h"
21
22 #define DEBUG_TYPE "mips-prelegalizer-combiner"
23
24 using namespace llvm;
25
26 namespace {
27 class MipsPreLegalizerCombinerInfo : public CombinerInfo {
28 public:
MipsPreLegalizerCombinerInfo()29 MipsPreLegalizerCombinerInfo()
30 : CombinerInfo(/*AllowIllegalOps*/ true, /*ShouldLegalizeIllegal*/ false,
31 /*LegalizerInfo*/ nullptr, /*EnableOpt*/ false,
32 /*EnableOptSize*/ false, /*EnableMinSize*/ false) {}
33 virtual bool combine(GISelChangeObserver &Observer, MachineInstr &MI,
34 MachineIRBuilder &B) const override;
35 };
36
combine(GISelChangeObserver & Observer,MachineInstr & MI,MachineIRBuilder & B) const37 bool MipsPreLegalizerCombinerInfo::combine(GISelChangeObserver &Observer,
38 MachineInstr &MI,
39 MachineIRBuilder &B) const {
40 CombinerHelper Helper(Observer, B);
41
42 switch (MI.getOpcode()) {
43 default:
44 return false;
45 case TargetOpcode::G_LOAD:
46 case TargetOpcode::G_SEXTLOAD:
47 case TargetOpcode::G_ZEXTLOAD:
48 return Helper.tryCombineExtendingLoads(MI);
49 }
50 return false;
51 }
52
53 // Pass boilerplate
54 // ================
55
56 class MipsPreLegalizerCombiner : public MachineFunctionPass {
57 public:
58 static char ID;
59
60 MipsPreLegalizerCombiner();
61
getPassName() const62 StringRef getPassName() const override { return "MipsPreLegalizerCombiner"; }
63
64 bool runOnMachineFunction(MachineFunction &MF) override;
65
66 void getAnalysisUsage(AnalysisUsage &AU) const override;
67 };
68 } // end anonymous namespace
69
getAnalysisUsage(AnalysisUsage & AU) const70 void MipsPreLegalizerCombiner::getAnalysisUsage(AnalysisUsage &AU) const {
71 AU.addRequired<TargetPassConfig>();
72 AU.setPreservesCFG();
73 getSelectionDAGFallbackAnalysisUsage(AU);
74 MachineFunctionPass::getAnalysisUsage(AU);
75 }
76
MipsPreLegalizerCombiner()77 MipsPreLegalizerCombiner::MipsPreLegalizerCombiner() : MachineFunctionPass(ID) {
78 initializeMipsPreLegalizerCombinerPass(*PassRegistry::getPassRegistry());
79 }
80
runOnMachineFunction(MachineFunction & MF)81 bool MipsPreLegalizerCombiner::runOnMachineFunction(MachineFunction &MF) {
82 if (MF.getProperties().hasProperty(
83 MachineFunctionProperties::Property::FailedISel))
84 return false;
85 auto *TPC = &getAnalysis<TargetPassConfig>();
86 MipsPreLegalizerCombinerInfo PCInfo;
87 Combiner C(PCInfo, TPC);
88 return C.combineMachineInstrs(MF, nullptr);
89 }
90
91 char MipsPreLegalizerCombiner::ID = 0;
92 INITIALIZE_PASS_BEGIN(MipsPreLegalizerCombiner, DEBUG_TYPE,
93 "Combine Mips machine instrs before legalization", false,
94 false)
95 INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
96 INITIALIZE_PASS_END(MipsPreLegalizerCombiner, DEBUG_TYPE,
97 "Combine Mips machine instrs before legalization", false,
98 false)
99
100 namespace llvm {
createMipsPreLegalizeCombiner()101 FunctionPass *createMipsPreLegalizeCombiner() {
102 return new MipsPreLegalizerCombiner();
103 }
104 } // end namespace llvm
105