llvm/tools/llvm-exegesis/lib/LlvmState.cpp

   1 //===-- LlvmState.cpp -------------------------------------------*- C++ -*-===//
   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 #include "LlvmState.h"
  10 #include "Target.h"
  11 #include "llvm/ADT/SmallVector.h"
  12 #include "llvm/MC/MCCodeEmitter.h"
  13 #include "llvm/MC/MCContext.h"
  14 #include "llvm/MC/MCFixup.h"
  15 #include "llvm/MC/MCObjectFileInfo.h"
  16 #include "llvm/MC/TargetRegistry.h"
  17 #include "llvm/Support/Host.h"
  18 #include "llvm/Support/raw_ostream.h"
  19 #include "llvm/Target/TargetMachine.h"
  20 #include "llvm/Target/TargetOptions.h"
  21
  22 namespace llvm {
  23 namespace exegesis {
  24
  25 LLVMState::LLVMState(const std::string &Triple, const std::string &CpuName,
  26                      const std::string &Features) {
  27   std::string Error;
  28   const Target *const TheTarget = TargetRegistry::lookupTarget(Triple, Error);
  29   assert(TheTarget && "unknown target for host");
  30   const TargetOptions Options;
  31   TheTargetMachine.reset(
  32       static_cast<LLVMTargetMachine *>(TheTarget->createTargetMachine(
  33           Triple, CpuName, Features, Options, Reloc::Model::Static)));
  34   assert(TheTargetMachine && "unable to create target machine");
  35   TheExegesisTarget = ExegesisTarget::lookup(TheTargetMachine->getTargetTriple());
  36   if (!TheExegesisTarget) {
  37     errs() << "no exegesis target for " << Triple << ", using default\n";
  38     TheExegesisTarget = &ExegesisTarget::getDefault();
  39   }
  40   PfmCounters = &TheExegesisTarget->getPfmCounters(CpuName);
  41
  42   BitVector ReservedRegs = getFunctionReservedRegs(getTargetMachine());
  43   for (const unsigned Reg : TheExegesisTarget->getUnavailableRegisters())
  44     ReservedRegs.set(Reg);
  45   RATC.reset(
  46       new RegisterAliasingTrackerCache(getRegInfo(), std::move(ReservedRegs)));
  47   IC.reset(new InstructionsCache(getInstrInfo(), getRATC()));
  48 }
  49
  50 LLVMState::LLVMState(const std::string &CpuName)
  51     : LLVMState(sys::getProcessTriple(),
  52                 CpuName.empty() ? sys::getHostCPUName().str() : CpuName, "") {}
  53
  54 std::unique_ptr<LLVMTargetMachine> LLVMState::createTargetMachine() const {
  55   return std::unique_ptr<LLVMTargetMachine>(static_cast<LLVMTargetMachine *>(
  56       TheTargetMachine->getTarget().createTargetMachine(
  57           TheTargetMachine->getTargetTriple().normalize(),
  58           TheTargetMachine->getTargetCPU(),
  59           TheTargetMachine->getTargetFeatureString(), TheTargetMachine->Options,
  60           Reloc::Model::Static)));
  61 }
  62
  63 bool LLVMState::canAssemble(const MCInst &Inst) const {
  64   MCContext Context(TheTargetMachine->getTargetTriple(),
  65                     TheTargetMachine->getMCAsmInfo(),
  66                     TheTargetMachine->getMCRegisterInfo(),
  67                     TheTargetMachine->getMCSubtargetInfo());
  68   std::unique_ptr<const MCCodeEmitter> CodeEmitter(
  69       TheTargetMachine->getTarget().createMCCodeEmitter(
  70           *TheTargetMachine->getMCInstrInfo(), *TheTargetMachine->getMCRegisterInfo(),
  71           Context));
  72   assert(CodeEmitter && "unable to create code emitter");
  73   SmallVector<char, 16> Tmp;
  74   raw_svector_ostream OS(Tmp);
  75   SmallVector<MCFixup, 4> Fixups;
  76   CodeEmitter->encodeInstruction(Inst, OS, Fixups,
  77                                  *TheTargetMachine->getMCSubtargetInfo());
  78   return Tmp.size() > 0;
  79 }
  80
  81 } // namespace exegesis
  82 } // namespace llvm