Details | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
14 | pmbaty | 1 | //==- llvm/CodeGen/SelectionDAGTargetInfo.h - SelectionDAG Info --*- 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 | // This file declares the SelectionDAGTargetInfo class, which targets can |
||
10 | // subclass to parameterize the SelectionDAG lowering and instruction |
||
11 | // selection process. |
||
12 | // |
||
13 | //===----------------------------------------------------------------------===// |
||
14 | |||
15 | #ifndef LLVM_CODEGEN_SELECTIONDAGTARGETINFO_H |
||
16 | #define LLVM_CODEGEN_SELECTIONDAGTARGETINFO_H |
||
17 | |||
18 | #include "llvm/CodeGen/MachineMemOperand.h" |
||
19 | #include "llvm/CodeGen/SelectionDAGNodes.h" |
||
20 | #include "llvm/Support/CodeGen.h" |
||
21 | #include <utility> |
||
22 | |||
23 | namespace llvm { |
||
24 | |||
25 | class SelectionDAG; |
||
26 | |||
27 | //===----------------------------------------------------------------------===// |
||
28 | /// Targets can subclass this to parameterize the |
||
29 | /// SelectionDAG lowering and instruction selection process. |
||
30 | /// |
||
31 | class SelectionDAGTargetInfo { |
||
32 | public: |
||
33 | explicit SelectionDAGTargetInfo() = default; |
||
34 | SelectionDAGTargetInfo(const SelectionDAGTargetInfo &) = delete; |
||
35 | SelectionDAGTargetInfo &operator=(const SelectionDAGTargetInfo &) = delete; |
||
36 | virtual ~SelectionDAGTargetInfo(); |
||
37 | |||
38 | /// Emit target-specific code that performs a memcpy. |
||
39 | /// This can be used by targets to provide code sequences for cases |
||
40 | /// that don't fit the target's parameters for simple loads/stores and can be |
||
41 | /// more efficient than using a library call. This function can return a null |
||
42 | /// SDValue if the target declines to use custom code and a different |
||
43 | /// lowering strategy should be used. |
||
44 | /// |
||
45 | /// If AlwaysInline is true, the size is constant and the target should not |
||
46 | /// emit any calls and is strongly encouraged to attempt to emit inline code |
||
47 | /// even if it is beyond the usual threshold because this intrinsic is being |
||
48 | /// expanded in a place where calls are not feasible (e.g. within the prologue |
||
49 | /// for another call). If the target chooses to decline an AlwaysInline |
||
50 | /// request here, legalize will resort to using simple loads and stores. |
||
51 | virtual SDValue EmitTargetCodeForMemcpy(SelectionDAG &DAG, const SDLoc &dl, |
||
52 | SDValue Chain, SDValue Op1, |
||
53 | SDValue Op2, SDValue Op3, |
||
54 | Align Alignment, bool isVolatile, |
||
55 | bool AlwaysInline, |
||
56 | MachinePointerInfo DstPtrInfo, |
||
57 | MachinePointerInfo SrcPtrInfo) const { |
||
58 | return SDValue(); |
||
59 | } |
||
60 | |||
61 | /// Emit target-specific code that performs a memmove. |
||
62 | /// This can be used by targets to provide code sequences for cases |
||
63 | /// that don't fit the target's parameters for simple loads/stores and can be |
||
64 | /// more efficient than using a library call. This function can return a null |
||
65 | /// SDValue if the target declines to use custom code and a different |
||
66 | /// lowering strategy should be used. |
||
67 | virtual SDValue EmitTargetCodeForMemmove( |
||
68 | SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Op1, |
||
69 | SDValue Op2, SDValue Op3, Align Alignment, bool isVolatile, |
||
70 | MachinePointerInfo DstPtrInfo, MachinePointerInfo SrcPtrInfo) const { |
||
71 | return SDValue(); |
||
72 | } |
||
73 | |||
74 | /// Emit target-specific code that performs a memset. |
||
75 | /// This can be used by targets to provide code sequences for cases |
||
76 | /// that don't fit the target's parameters for simple stores and can be more |
||
77 | /// efficient than using a library call. This function can return a null |
||
78 | /// SDValue if the target declines to use custom code and a different |
||
79 | /// lowering strategy should be used. Note that if AlwaysInline is true the |
||
80 | /// function has to return a valid SDValue. |
||
81 | virtual SDValue EmitTargetCodeForMemset(SelectionDAG &DAG, const SDLoc &dl, |
||
82 | SDValue Chain, SDValue Op1, |
||
83 | SDValue Op2, SDValue Op3, |
||
84 | Align Alignment, bool isVolatile, |
||
85 | bool AlwaysInline, |
||
86 | MachinePointerInfo DstPtrInfo) const { |
||
87 | return SDValue(); |
||
88 | } |
||
89 | |||
90 | /// Emit target-specific code that performs a memcmp/bcmp, in cases where that is |
||
91 | /// faster than a libcall. The first returned SDValue is the result of the |
||
92 | /// memcmp and the second is the chain. Both SDValues can be null if a normal |
||
93 | /// libcall should be used. |
||
94 | virtual std::pair<SDValue, SDValue> |
||
95 | EmitTargetCodeForMemcmp(SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, |
||
96 | SDValue Op1, SDValue Op2, SDValue Op3, |
||
97 | MachinePointerInfo Op1PtrInfo, |
||
98 | MachinePointerInfo Op2PtrInfo) const { |
||
99 | return std::make_pair(SDValue(), SDValue()); |
||
100 | } |
||
101 | |||
102 | /// Emit target-specific code that performs a memchr, in cases where that is |
||
103 | /// faster than a libcall. The first returned SDValue is the result of the |
||
104 | /// memchr and the second is the chain. Both SDValues can be null if a normal |
||
105 | /// libcall should be used. |
||
106 | virtual std::pair<SDValue, SDValue> |
||
107 | EmitTargetCodeForMemchr(SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, |
||
108 | SDValue Src, SDValue Char, SDValue Length, |
||
109 | MachinePointerInfo SrcPtrInfo) const { |
||
110 | return std::make_pair(SDValue(), SDValue()); |
||
111 | } |
||
112 | |||
113 | /// Emit target-specific code that performs a strcpy or stpcpy, in cases |
||
114 | /// where that is faster than a libcall. |
||
115 | /// The first returned SDValue is the result of the copy (the start |
||
116 | /// of the destination string for strcpy, a pointer to the null terminator |
||
117 | /// for stpcpy) and the second is the chain. Both SDValues can be null |
||
118 | /// if a normal libcall should be used. |
||
119 | virtual std::pair<SDValue, SDValue> |
||
120 | EmitTargetCodeForStrcpy(SelectionDAG &DAG, const SDLoc &DL, SDValue Chain, |
||
121 | SDValue Dest, SDValue Src, |
||
122 | MachinePointerInfo DestPtrInfo, |
||
123 | MachinePointerInfo SrcPtrInfo, bool isStpcpy) const { |
||
124 | return std::make_pair(SDValue(), SDValue()); |
||
125 | } |
||
126 | |||
127 | /// Emit target-specific code that performs a strcmp, in cases where that is |
||
128 | /// faster than a libcall. |
||
129 | /// The first returned SDValue is the result of the strcmp and the second is |
||
130 | /// the chain. Both SDValues can be null if a normal libcall should be used. |
||
131 | virtual std::pair<SDValue, SDValue> |
||
132 | EmitTargetCodeForStrcmp(SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, |
||
133 | SDValue Op1, SDValue Op2, |
||
134 | MachinePointerInfo Op1PtrInfo, |
||
135 | MachinePointerInfo Op2PtrInfo) const { |
||
136 | return std::make_pair(SDValue(), SDValue()); |
||
137 | } |
||
138 | |||
139 | virtual std::pair<SDValue, SDValue> |
||
140 | EmitTargetCodeForStrlen(SelectionDAG &DAG, const SDLoc &DL, SDValue Chain, |
||
141 | SDValue Src, MachinePointerInfo SrcPtrInfo) const { |
||
142 | return std::make_pair(SDValue(), SDValue()); |
||
143 | } |
||
144 | |||
145 | virtual std::pair<SDValue, SDValue> |
||
146 | EmitTargetCodeForStrnlen(SelectionDAG &DAG, const SDLoc &DL, SDValue Chain, |
||
147 | SDValue Src, SDValue MaxLength, |
||
148 | MachinePointerInfo SrcPtrInfo) const { |
||
149 | return std::make_pair(SDValue(), SDValue()); |
||
150 | } |
||
151 | |||
152 | virtual SDValue EmitTargetCodeForSetTag(SelectionDAG &DAG, const SDLoc &dl, |
||
153 | SDValue Chain, SDValue Addr, |
||
154 | SDValue Size, |
||
155 | MachinePointerInfo DstPtrInfo, |
||
156 | bool ZeroData) const { |
||
157 | return SDValue(); |
||
158 | } |
||
159 | |||
160 | // Return true if the DAG Combiner should disable generic combines. |
||
161 | virtual bool disableGenericCombines(CodeGenOpt::Level OptLevel) const { |
||
162 | return false; |
||
163 | } |
||
164 | }; |
||
165 | |||
166 | } // end namespace llvm |
||
167 | |||
168 | #endif // LLVM_CODEGEN_SELECTIONDAGTARGETINFO_H |