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