llvm/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/MC/TargetRegistry.h"
  16 #include "llvm/TargetParser/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 static cl::opt<bool> Disable_ldsx("disable-ldsx", cl::Hidden, cl::init(false),
  27   cl::desc("Disable ldsx insns"));
  28 static cl::opt<bool> Disable_movsx("disable-movsx", cl::Hidden, cl::init(false),
  29   cl::desc("Disable movsx insns"));
  30 static cl::opt<bool> Disable_bswap("disable-bswap", cl::Hidden, cl::init(false),
  31   cl::desc("Disable bswap insns"));
  32 static cl::opt<bool> Disable_sdiv_smod("disable-sdiv-smod", cl::Hidden,
  33   cl::init(false), cl::desc("Disable sdiv/smod insns"));
  34 static cl::opt<bool> Disable_gotol("disable-gotol", cl::Hidden, cl::init(false),
  35   cl::desc("Disable gotol insn"));
  36 static cl::opt<bool>
  37     Disable_StoreImm("disable-storeimm", cl::Hidden, cl::init(false),
  38                      cl::desc("Disable BPF_ST (immediate store) insn"));
  39
  40 void BPFSubtarget::anchor() {}
  41
  42 BPFSubtarget &BPFSubtarget::initializeSubtargetDependencies(StringRef CPU,
  43                                                             StringRef FS) {
  44   initializeEnvironment();
  45   initSubtargetFeatures(CPU, FS);
  46   ParseSubtargetFeatures(CPU, /*TuneCPU*/ CPU, FS);
  47   return *this;
  48 }
  49
  50 void BPFSubtarget::initializeEnvironment() {
  51   HasJmpExt = false;
  52   HasJmp32 = false;
  53   HasAlu32 = false;
  54   UseDwarfRIS = false;
  55   HasLdsx = false;
  56   HasMovsx = false;
  57   HasBswap = false;
  58   HasSdivSmod = false;
  59   HasGotol = false;
  60   HasStoreImm = false;
  61 }
  62
  63 void BPFSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
  64   if (CPU == "probe")
  65     CPU = sys::detail::getHostCPUNameForBPF();
  66   if (CPU == "generic" || CPU == "v1")
  67     return;
  68   if (CPU == "v2") {
  69     HasJmpExt = true;
  70     return;
  71   }
  72   if (CPU == "v3") {
  73     HasJmpExt = true;
  74     HasJmp32 = true;
  75     HasAlu32 = true;
  76     return;
  77   }
  78   if (CPU == "v4") {
  79     HasJmpExt = true;
  80     HasJmp32 = true;
  81     HasAlu32 = true;
  82     HasLdsx = !Disable_ldsx;
  83     HasMovsx = !Disable_movsx;
  84     HasBswap = !Disable_bswap;
  85     HasSdivSmod = !Disable_sdiv_smod;
  86     HasGotol = !Disable_gotol;
  87     HasStoreImm = !Disable_StoreImm;
  88     return;
  89   }
  90 }
  91
  92 BPFSubtarget::BPFSubtarget(const Triple &TT, const std::string &CPU,
  93                            const std::string &FS, const TargetMachine &TM)
  94     : BPFGenSubtargetInfo(TT, CPU, /*TuneCPU*/ CPU, FS),
  95       FrameLowering(initializeSubtargetDependencies(CPU, FS)),
  96       TLInfo(TM, *this) {}