LLVM  9.0.0svn
CombinerInfo.h
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1 //===- llvm/CodeGen/GlobalISel/CombinerInfo.h ------*- C++ -*-===//
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 /// Interface for Targets to specify which operations are combined how and when.
10 ///
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CODEGEN_GLOBALISEL_COMBINER_INFO_H
14 #define LLVM_CODEGEN_GLOBALISEL_COMBINER_INFO_H
15 
16 #include <cassert>
17 namespace llvm {
18 
19 class GISelChangeObserver;
20 class LegalizerInfo;
21 class MachineInstr;
22 class MachineIRBuilder;
23 class MachineRegisterInfo;
24 
25 // Contains information relevant to enabling/disabling various combines for a
26 // pass.
27 class CombinerInfo {
28 public:
29  CombinerInfo(bool AllowIllegalOps, bool ShouldLegalizeIllegal,
31  : IllegalOpsAllowed(AllowIllegalOps),
32  LegalizeIllegalOps(ShouldLegalizeIllegal), LInfo(LInfo) {
33  assert(((AllowIllegalOps || !LegalizeIllegalOps) || LInfo) &&
34  "Expecting legalizerInfo when illegalops not allowed");
35  }
36  virtual ~CombinerInfo() = default;
37  /// If \p IllegalOpsAllowed is false, the CombinerHelper will make use of
38  /// the legalizerInfo to check for legality before each transformation.
39  bool IllegalOpsAllowed; // TODO: Make use of this.
40 
41  /// If \p LegalizeIllegalOps is true, the Combiner will also legalize the
42  /// illegal ops that are created.
43  bool LegalizeIllegalOps; // TODO: Make use of this.
45 
46  /// Attempt to combine instructions using MI as the root.
47  ///
48  /// Use Observer to report the creation, modification, and erasure of
49  /// instructions. GISelChangeObserver will automatically report certain
50  /// kinds of operations. These operations are:
51  /// * Instructions that are newly inserted into the MachineFunction
52  /// * Instructions that are erased from the MachineFunction.
53  ///
54  /// However, it is important to report instruction modification and this is
55  /// not automatic.
56  virtual bool combine(GISelChangeObserver &Observer, MachineInstr &MI,
57  MachineIRBuilder &B) const = 0;
58 };
59 } // namespace llvm
60 
61 #endif
This class represents lattice values for constants.
Definition: AllocatorList.h:23
virtual ~CombinerInfo()=default
virtual bool combine(GISelChangeObserver &Observer, MachineInstr &MI, MachineIRBuilder &B) const =0
Attempt to combine instructions using MI as the root.
const LegalizerInfo * LInfo
Definition: CombinerInfo.h:44
CombinerInfo(bool AllowIllegalOps, bool ShouldLegalizeIllegal, LegalizerInfo *LInfo)
Definition: CombinerInfo.h:29
Abstract class that contains various methods for clients to notify about changes. ...
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
Helper class to build MachineInstr.
bool IllegalOpsAllowed
If IllegalOpsAllowed is false, the CombinerHelper will make use of the legalizerInfo to check for leg...
Definition: CombinerInfo.h:39
bool LegalizeIllegalOps
If LegalizeIllegalOps is true, the Combiner will also legalize the illegal ops that are created...
Definition: CombinerInfo.h:43
Representation of each machine instruction.
Definition: MachineInstr.h:63
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
IRTranslator LLVM IR MI