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 "llvm/MC/TargetRegistry.h"
16 #include "llvm/Support/Host.h"
17 
18 using namespace llvm;
19 
20 #define DEBUG_TYPE "bpf-subtarget"
21 
22 #define GET_SUBTARGETINFO_TARGET_DESC
23 #define GET_SUBTARGETINFO_CTOR
24 #include "BPFGenSubtargetInfo.inc"
25 
26 void BPFSubtarget::anchor() {}
27 
28 BPFSubtarget &BPFSubtarget::initializeSubtargetDependencies(StringRef CPU,
29                                                             StringRef FS) {
30   initializeEnvironment();
31   initSubtargetFeatures(CPU, FS);
32   ParseSubtargetFeatures(CPU, /*TuneCPU*/ CPU, FS);
33   return *this;
34 }
35 
36 void BPFSubtarget::initializeEnvironment() {
37   HasJmpExt = false;
38   HasJmp32 = false;
39   HasAlu32 = false;
40   UseDwarfRIS = false;
41 }
42 
43 void BPFSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
44   if (CPU == "probe")
45     CPU = sys::detail::getHostCPUNameForBPF();
46   if (CPU == "generic" || CPU == "v1")
47     return;
48   if (CPU == "v2") {
49     HasJmpExt = true;
50     return;
51   }
52   if (CPU == "v3") {
53     HasJmpExt = true;
54     HasJmp32 = true;
55     HasAlu32 = true;
56     return;
57   }
58 }
59 
60 BPFSubtarget::BPFSubtarget(const Triple &TT, const std::string &CPU,
61                            const std::string &FS, const TargetMachine &TM)
62     : BPFGenSubtargetInfo(TT, CPU, /*TuneCPU*/ CPU, FS),
63       FrameLowering(initializeSubtargetDependencies(CPU, FS)),
64       TLInfo(TM, *this) {}
65