LLVM  10.0.0svn
MipsPreLegalizerCombiner.cpp
Go to the documentation of this file.
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"
20 
21 #define DEBUG_TYPE "mips-prelegalizer-combiner"
22 
23 using namespace llvm;
24 
25 namespace {
26 class MipsPreLegalizerCombinerInfo : public CombinerInfo {
27 public:
28  MipsPreLegalizerCombinerInfo()
29  : CombinerInfo(/*AllowIllegalOps*/ true, /*ShouldLegalizeIllegal*/ false,
30  /*LegalizerInfo*/ nullptr, /*EnableOpt*/ false,
31  /*EnableOptSize*/ false, /*EnableMinSize*/ false) {}
32  virtual bool combine(GISelChangeObserver &Observer, MachineInstr &MI,
33  MachineIRBuilder &B) const override;
34 };
35 
36 bool MipsPreLegalizerCombinerInfo::combine(GISelChangeObserver &Observer,
38  MachineIRBuilder &B) const {
39  CombinerHelper Helper(Observer, B);
40 
41  switch (MI.getOpcode()) {
42  default:
43  return false;
44  case TargetOpcode::G_LOAD:
45  case TargetOpcode::G_SEXTLOAD:
46  case TargetOpcode::G_ZEXTLOAD:
47  return Helper.tryCombineExtendingLoads(MI);
48  }
49  return false;
50 }
51 
52 // Pass boilerplate
53 // ================
54 
55 class MipsPreLegalizerCombiner : public MachineFunctionPass {
56 public:
57  static char ID;
58 
59  MipsPreLegalizerCombiner();
60 
61  StringRef getPassName() const override { return "MipsPreLegalizerCombiner"; }
62 
63  bool runOnMachineFunction(MachineFunction &MF) override;
64 
65  void getAnalysisUsage(AnalysisUsage &AU) const override;
66 };
67 } // end anonymous namespace
68 
69 void MipsPreLegalizerCombiner::getAnalysisUsage(AnalysisUsage &AU) const {
71  AU.setPreservesCFG();
74 }
75 
76 MipsPreLegalizerCombiner::MipsPreLegalizerCombiner() : MachineFunctionPass(ID) {
78 }
79 
80 bool MipsPreLegalizerCombiner::runOnMachineFunction(MachineFunction &MF) {
81  if (MF.getProperties().hasProperty(
83  return false;
84  auto *TPC = &getAnalysis<TargetPassConfig>();
85  MipsPreLegalizerCombinerInfo PCInfo;
86  Combiner C(PCInfo, TPC);
87  return C.combineMachineInstrs(MF, nullptr);
88 }
89 
91 INITIALIZE_PASS_BEGIN(MipsPreLegalizerCombiner, DEBUG_TYPE,
92  "Combine Mips machine instrs before legalization", false,
93  false)
95 INITIALIZE_PASS_END(MipsPreLegalizerCombiner, DEBUG_TYPE,
96  "Combine Mips machine instrs before legalization", false,
97  false)
98 
99 namespace llvm {
101  return new MipsPreLegalizerCombiner();
102 }
103 } // end namespace llvm
uint64_t CallInst * C
static PassRegistry * getPassRegistry()
getPassRegistry - Access the global registry object, which is automatically initialized at applicatio...
coro Split coroutine into a set of functions driving its state machine
Definition: CoroSplit.cpp:1597
This class represents lattice values for constants.
Definition: AllocatorList.h:23
void getSelectionDAGFallbackAnalysisUsage(AnalysisUsage &AU)
Modify analysis usage so it preserves passes required for the SelectionDAG fallback.
Definition: Utils.cpp:431
const MachineFunctionProperties & getProperties() const
Get the function properties.
AnalysisUsage & addRequired()
#define INITIALIZE_PASS_DEPENDENCY(depName)
Definition: PassSupport.h:50
MachineFunctionPass - This class adapts the FunctionPass interface to allow convenient creation of pa...
unsigned getOpcode() const
Returns the opcode of this MachineInstr.
Definition: MachineInstr.h:411
Combine Mips machine instrs before legalization
Target-Independent Code Generator Pass Configuration Options.
Abstract class that contains various methods for clients to notify about changes. ...
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
void getAnalysisUsage(AnalysisUsage &AU) const override
getAnalysisUsage - Subclasses that override getAnalysisUsage must call this.
Helper class to build MachineInstr.
FunctionPass * createMipsPreLegalizeCombiner()
INITIALIZE_PASS_BEGIN(MipsPreLegalizerCombiner, DEBUG_TYPE, "Combine Mips machine instrs before legalization", false, false) INITIALIZE_PASS_END(MipsPreLegalizerCombiner
Represent the analysis usage information of a pass.
#define DEBUG_TYPE
bool tryCombineExtendingLoads(MachineInstr &MI)
If MI is extend that consumes the result of a load, try to combine it.
FunctionPass class - This class is used to implement most global optimizations.
Definition: Pass.h:284
bool combineMachineInstrs(MachineFunction &MF, GISelCSEInfo *CSEInfo)
If CSEInfo is not null, then the Combiner will setup observer for CSEInfo and instantiate a CSEMIRBui...
Definition: Combiner.cpp:98
INITIALIZE_PASS_END(RegBankSelect, DEBUG_TYPE, "Assign register bank of generic virtual registers", false, false) RegBankSelect
void setPreservesCFG()
This function should be called by the pass, iff they do not:
Definition: Pass.cpp:301
Representation of each machine instruction.
Definition: MachineInstr.h:64
bool hasProperty(Property P) const
IRTranslator LLVM IR MI
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
void initializeMipsPreLegalizerCombinerPass(PassRegistry &)