lib/Target/BPF/BPFSubtarget.cpp

   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/Support/Host.h"
  16 #include "llvm/Support/TargetRegistry.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, 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     return;
  56   }
  57 }
  58
  59 BPFSubtarget::BPFSubtarget(const Triple &TT, const std::string &CPU,
  60                            const std::string &FS, const TargetMachine &TM)
  61     : BPFGenSubtargetInfo(TT, CPU, FS), InstrInfo(),
  62       FrameLowering(initializeSubtargetDependencies(CPU, FS)),
  63       TLInfo(TM, *this) {}