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
anchor()44 void BPFSubtarget::anchor() {}
45
initializeSubtargetDependencies(StringRef CPU,StringRef FS)46 BPFSubtarget &BPFSubtarget::initializeSubtargetDependencies(StringRef CPU,
47 StringRef FS) {
48 initializeEnvironment();
49 initSubtargetFeatures(CPU, FS);
50 ParseSubtargetFeatures(CPU, /*TuneCPU*/ CPU, FS);
51 return *this;
52 }
53
initializeEnvironment()54 void BPFSubtarget::initializeEnvironment() {
55 HasJmpExt = false;
56 HasJmp32 = false;
57 HasAlu32 = false;
58 UseDwarfRIS = false;
59 HasLdsx = false;
60 HasMovsx = false;
61 HasBswap = false;
62 HasSdivSmod = false;
63 HasGotol = false;
64 HasStoreImm = false;
65 }
66
initSubtargetFeatures(StringRef CPU,StringRef FS)67 void BPFSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
68 if (CPU == "probe")
69 CPU = sys::detail::getHostCPUNameForBPF();
70 if (CPU == "generic" || CPU == "v1")
71 return;
72 if (CPU == "v2") {
73 HasJmpExt = true;
74 return;
75 }
76 if (CPU == "v3") {
77 HasJmpExt = true;
78 HasJmp32 = true;
79 HasAlu32 = true;
80 return;
81 }
82 if (CPU == "v4") {
83 HasJmpExt = true;
84 HasJmp32 = true;
85 HasAlu32 = true;
86 HasLdsx = !Disable_ldsx;
87 HasMovsx = !Disable_movsx;
88 HasBswap = !Disable_bswap;
89 HasSdivSmod = !Disable_sdiv_smod;
90 HasGotol = !Disable_gotol;
91 HasStoreImm = !Disable_StoreImm;
92 return;
93 }
94 }
95
BPFSubtarget(const Triple & TT,const std::string & CPU,const std::string & FS,const TargetMachine & TM)96 BPFSubtarget::BPFSubtarget(const Triple &TT, const std::string &CPU,
97 const std::string &FS, const TargetMachine &TM)
98 : BPFGenSubtargetInfo(TT, CPU, /*TuneCPU*/ CPU, FS),
99 FrameLowering(initializeSubtargetDependencies(CPU, FS)),
100 TLInfo(TM, *this) {
101 IsLittleEndian = TT.isLittleEndian();
102
103 CallLoweringInfo.reset(new BPFCallLowering(*getTargetLowering()));
104 Legalizer.reset(new BPFLegalizerInfo(*this));
105 auto *RBI = new BPFRegisterBankInfo(*getRegisterInfo());
106 RegBankInfo.reset(RBI);
107
108 InstSelector.reset(createBPFInstructionSelector(
109 *static_cast<const BPFTargetMachine *>(&TM), *this, *RBI));
110 }
111
getCallLowering() const112 const CallLowering *BPFSubtarget::getCallLowering() const {
113 return CallLoweringInfo.get();
114 }
115
getInstructionSelector() const116 InstructionSelector *BPFSubtarget::getInstructionSelector() const {
117 return InstSelector.get();
118 }
119
getLegalizerInfo() const120 const LegalizerInfo *BPFSubtarget::getLegalizerInfo() const {
121 return Legalizer.get();
122 }
123
getRegBankInfo() const124 const RegisterBankInfo *BPFSubtarget::getRegBankInfo() const {
125 return RegBankInfo.get();
126 }
127