1 //===- llvm/CodeGen/GlobalISel/CombinerInfo.h ------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 /// Interface for Targets to specify which operations are combined how and when.
11 //===----------------------------------------------------------------------===//
13 #ifndef LLVM_CODEGEN_GLOBALISEL_COMBINER_INFO_H
14 #define LLVM_CODEGEN_GLOBALISEL_COMBINER_INFO_H
19 class GISelChangeObserver
;
22 class MachineIRBuilder
;
23 class MachineRegisterInfo
;
25 // Contains information relevant to enabling/disabling various combines for a
29 CombinerInfo(bool AllowIllegalOps
, bool ShouldLegalizeIllegal
,
30 LegalizerInfo
*LInfo
, bool OptEnabled
, bool OptSize
,
32 : IllegalOpsAllowed(AllowIllegalOps
),
33 LegalizeIllegalOps(ShouldLegalizeIllegal
), LInfo(LInfo
),
34 EnableOpt(OptEnabled
), EnableOptSize(OptSize
), EnableMinSize(MinSize
) {
35 assert(((AllowIllegalOps
|| !LegalizeIllegalOps
) || LInfo
) &&
36 "Expecting legalizerInfo when illegalops not allowed");
38 virtual ~CombinerInfo() = default;
39 /// If \p IllegalOpsAllowed is false, the CombinerHelper will make use of
40 /// the legalizerInfo to check for legality before each transformation.
41 bool IllegalOpsAllowed
; // TODO: Make use of this.
43 /// If \p LegalizeIllegalOps is true, the Combiner will also legalize the
44 /// illegal ops that are created.
45 bool LegalizeIllegalOps
; // TODO: Make use of this.
46 const LegalizerInfo
*LInfo
;
48 /// Whether optimizations should be enabled. This is to distinguish between
49 /// uses of the combiner unconditionally and only when optimizations are
50 /// specifically enabled/
52 /// Whether we're optimizing for size.
54 /// Whether we're optimizing for minsize (-Oz).
57 /// Attempt to combine instructions using MI as the root.
59 /// Use Observer to report the creation, modification, and erasure of
60 /// instructions. GISelChangeObserver will automatically report certain
61 /// kinds of operations. These operations are:
62 /// * Instructions that are newly inserted into the MachineFunction
63 /// * Instructions that are erased from the MachineFunction.
65 /// However, it is important to report instruction modification and this is
67 virtual bool combine(GISelChangeObserver
&Observer
, MachineInstr
&MI
,
68 MachineIRBuilder
&B
) const = 0;