1//===- PPCGenRegisterBankInfo.def -------------------------------*- 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/// \file
9/// This file defines all the static objects used by PPCRegisterBankInfo.
10/// \todo This should be generated by TableGen, because the logic here can be
11/// derived from register bank definition. Not yet implemented.
12//===----------------------------------------------------------------------===//
13
14namespace llvm {
15const RegisterBankInfo::PartialMapping PPCGenRegisterBankInfo::PartMappings[]{
16 /* StartIdx, Length, RegBank */
17 // 0: GPR 32-bit value.
18 {0, 32, PPC::GPRRegBank},
19 // 1: GPR 64-bit value.
20 {0, 64, PPC::GPRRegBank},
21 // 2: FPR 32-bit value
22 {0, 32, PPC::FPRRegBank},
23 // 3: FPR 64-bit value
24 {0, 64, PPC::FPRRegBank},
25 // 4: 128-bit vector (VSX, Altivec)
26 {0, 128, PPC::VECRegBank},
27 // 5: CR 4-bit value
28 {0, 4, PPC::CRRegBank},
29};
30
31// ValueMappings.
32// Pointers to the entries in this array are returned by getValueMapping() and
33// getCopyMapping().
34//
35// The array has the following structure:
36// - At index 0 is the invalid entry.
37// - After that, the mappings for the register types from PartialMappingIdx
38// follow. Each mapping consists of 3 entries, which is needed to cover
39// 3-operands instructions.
40// - Last, mappings for cross-register bank moves follow. Since COPY has only
41// 2 operands, a mapping consists of 2 entries.
42const RegisterBankInfo::ValueMapping PPCGenRegisterBankInfo::ValMappings[]{
43 /* BreakDown, NumBreakDowns */
44 // 0: invalid
45 {nullptr, 0},
46 // 1: GPR 32-bit value.
47 {&PPCGenRegisterBankInfo::PartMappings[PMI_GPR32 - PMI_Min], 1},
48 {&PPCGenRegisterBankInfo::PartMappings[PMI_GPR32 - PMI_Min], 1},
49 {&PPCGenRegisterBankInfo::PartMappings[PMI_GPR32 - PMI_Min], 1},
50 // 4: GPR 64-bit value.
51 {&PPCGenRegisterBankInfo::PartMappings[PMI_GPR64 - PMI_Min], 1},
52 {&PPCGenRegisterBankInfo::PartMappings[PMI_GPR64 - PMI_Min], 1},
53 {&PPCGenRegisterBankInfo::PartMappings[PMI_GPR64 - PMI_Min], 1},
54 // 7: FPR 32-bit value.
55 {&PPCGenRegisterBankInfo::PartMappings[PMI_FPR32 - PMI_Min], 1},
56 {&PPCGenRegisterBankInfo::PartMappings[PMI_FPR32 - PMI_Min], 1},
57 {&PPCGenRegisterBankInfo::PartMappings[PMI_FPR32 - PMI_Min], 1},
58 // 10: FPR 64-bit value.
59 {&PPCGenRegisterBankInfo::PartMappings[PMI_FPR64 - PMI_Min], 1},
60 {&PPCGenRegisterBankInfo::PartMappings[PMI_FPR64 - PMI_Min], 1},
61 {&PPCGenRegisterBankInfo::PartMappings[PMI_FPR64 - PMI_Min], 1},
62 // 13: 128-bit vector.
63 {&PPCGenRegisterBankInfo::PartMappings[PMI_VEC128 - PMI_Min], 1},
64 {&PPCGenRegisterBankInfo::PartMappings[PMI_VEC128 - PMI_Min], 1},
65 {&PPCGenRegisterBankInfo::PartMappings[PMI_VEC128 - PMI_Min], 1},
66 // 16: CR 4-bit value.
67 {&PPCGenRegisterBankInfo::PartMappings[PMI_CR - PMI_Min], 1},
68};
69
70// TODO Too simple!
71const RegisterBankInfo::ValueMapping *
72PPCGenRegisterBankInfo::getValueMapping(PartialMappingIdx RBIdx) {
73 assert(RBIdx != PartialMappingIdx::PMI_None && "No mapping needed for that");
74
75 unsigned ValMappingIdx = RBIdx - PMI_Min;
76
77 return &ValMappings[1 + 3 * ValMappingIdx];
78}
79
80const PPCGenRegisterBankInfo::PartialMappingIdx
81 PPCGenRegisterBankInfo::BankIDToCopyMapIdx[]{
82 PMI_None,
83 PMI_FPR64, // FPR
84 PMI_GPR64, // GPR
85 PMI_VEC128, // VEC
86};
87
88// TODO Too simple!
89const RegisterBankInfo::ValueMapping *
90PPCGenRegisterBankInfo::getCopyMapping(unsigned DstBankID, unsigned SrcBankID,
91 unsigned Size) {
92 assert(DstBankID < PPC::NumRegisterBanks && "Invalid bank ID");
93 assert(SrcBankID < PPC::NumRegisterBanks && "Invalid bank ID");
94 PartialMappingIdx DstRBIdx = BankIDToCopyMapIdx[DstBankID];
95 PartialMappingIdx SrcRBIdx = BankIDToCopyMapIdx[SrcBankID];
96 assert(DstRBIdx != PMI_None && "No such mapping");
97 assert(SrcRBIdx != PMI_None && "No such mapping");
98
99 if (DstRBIdx == SrcRBIdx)
100 return getValueMapping(RBIdx: DstRBIdx);
101
102 assert(Size <= 128 && "Can currently handle types up to 128 bits (vectors)!");
103 // TODO: This function needs to be updated to handle all cases for
104 // GPRs, FPRs and vectors. It currently only handles bitcasting to
105 // the same type and has only mainly been tested for bitcasting
106 // between different vector types.
107 unsigned ValMappingIdx = DstRBIdx - PMI_Min;
108
109 return &ValMappings[1 + 3 * ValMappingIdx];
110}
111
112} // namespace llvm
113