1 //===-- BPFSubtarget.cpp - BPF Subtarget Information ----------------------===//
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 implements the BPF specific subclass of TargetSubtargetInfo.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "BPFSubtarget.h"
14 #include "BPF.h"
15 #include "BPFTargetMachine.h"
16 #include "GISel/BPFCallLowering.h"
17 #include "GISel/BPFLegalizerInfo.h"
18 #include "GISel/BPFRegisterBankInfo.h"
19 #include "llvm/MC/TargetRegistry.h"
20 #include "llvm/TargetParser/Host.h"
21
22 using namespace llvm;
23
24 #define DEBUG_TYPE "bpf-subtarget"
25
26 #define GET_SUBTARGETINFO_TARGET_DESC
27 #define GET_SUBTARGETINFO_CTOR
28 #include "BPFGenSubtargetInfo.inc"
29
30 static cl::opt<bool> Disable_ldsx("disable-ldsx", cl::Hidden, cl::init(false),
31 cl::desc("Disable ldsx insns"));
32 static cl::opt<bool> Disable_movsx("disable-movsx", cl::Hidden, cl::init(false),
33 cl::desc("Disable movsx insns"));
34 static cl::opt<bool> Disable_bswap("disable-bswap", cl::Hidden, cl::init(false),
35 cl::desc("Disable bswap insns"));
36 static cl::opt<bool> Disable_sdiv_smod("disable-sdiv-smod", cl::Hidden,
37 cl::init(false), cl::desc("Disable sdiv/smod insns"));
38 static cl::opt<bool> Disable_gotol("disable-gotol", cl::Hidden, cl::init(false),
39 cl::desc("Disable gotol insn"));
40 static cl::opt<bool>
41 Disable_StoreImm("disable-storeimm", cl::Hidden, cl::init(false),
42 cl::desc("Disable BPF_ST (immediate store) insn"));
43 static cl::opt<bool> Disable_load_acq_store_rel(
44 "disable-load-acq-store-rel", cl::Hidden, cl::init(false),
45 cl::desc("Disable load-acquire and store-release insns"));
46
anchor()47 void BPFSubtarget::anchor() {}
48
initializeSubtargetDependencies(StringRef CPU,StringRef FS)49 BPFSubtarget &BPFSubtarget::initializeSubtargetDependencies(StringRef CPU,
50 StringRef FS) {
51 initializeEnvironment();
52 initSubtargetFeatures(CPU, FS);
53 ParseSubtargetFeatures(CPU, /*TuneCPU*/ CPU, FS);
54 return *this;
55 }
56
initializeEnvironment()57 void BPFSubtarget::initializeEnvironment() {
58 HasJmpExt = false;
59 HasJmp32 = false;
60 HasAlu32 = false;
61 UseDwarfRIS = false;
62 HasLdsx = false;
63 HasMovsx = false;
64 HasBswap = false;
65 HasSdivSmod = false;
66 HasGotol = false;
67 HasStoreImm = false;
68 HasLoadAcqStoreRel = false;
69 }
70
initSubtargetFeatures(StringRef CPU,StringRef FS)71 void BPFSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
72 if (CPU.empty())
73 CPU = "v3";
74 if (CPU == "probe")
75 CPU = sys::detail::getHostCPUNameForBPF();
76 if (CPU == "generic" || CPU == "v1")
77 return;
78 if (CPU == "v2") {
79 HasJmpExt = true;
80 return;
81 }
82 if (CPU == "v3") {
83 HasJmpExt = true;
84 HasJmp32 = true;
85 HasAlu32 = true;
86 return;
87 }
88 if (CPU == "v4") {
89 HasJmpExt = true;
90 HasJmp32 = true;
91 HasAlu32 = true;
92 HasLdsx = !Disable_ldsx;
93 HasMovsx = !Disable_movsx;
94 HasBswap = !Disable_bswap;
95 HasSdivSmod = !Disable_sdiv_smod;
96 HasGotol = !Disable_gotol;
97 HasStoreImm = !Disable_StoreImm;
98 HasLoadAcqStoreRel = !Disable_load_acq_store_rel;
99 return;
100 }
101 }
102
BPFSubtarget(const Triple & TT,const std::string & CPU,const std::string & FS,const TargetMachine & TM)103 BPFSubtarget::BPFSubtarget(const Triple &TT, const std::string &CPU,
104 const std::string &FS, const TargetMachine &TM)
105 : BPFGenSubtargetInfo(TT, CPU, /*TuneCPU*/ CPU, FS),
106 FrameLowering(initializeSubtargetDependencies(CPU, FS)),
107 TLInfo(TM, *this) {
108 IsLittleEndian = TT.isLittleEndian();
109
110 CallLoweringInfo.reset(new BPFCallLowering(*getTargetLowering()));
111 Legalizer.reset(new BPFLegalizerInfo(*this));
112 auto *RBI = new BPFRegisterBankInfo(*getRegisterInfo());
113 RegBankInfo.reset(RBI);
114
115 InstSelector.reset(createBPFInstructionSelector(
116 *static_cast<const BPFTargetMachine *>(&TM), *this, *RBI));
117 }
118
getCallLowering() const119 const CallLowering *BPFSubtarget::getCallLowering() const {
120 return CallLoweringInfo.get();
121 }
122
getInstructionSelector() const123 InstructionSelector *BPFSubtarget::getInstructionSelector() const {
124 return InstSelector.get();
125 }
126
getLegalizerInfo() const127 const LegalizerInfo *BPFSubtarget::getLegalizerInfo() const {
128 return Legalizer.get();
129 }
130
getRegBankInfo() const131 const RegisterBankInfo *BPFSubtarget::getRegBankInfo() const {
132 return RegBankInfo.get();
133 }
134