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/Host.h"
17 #include "llvm/Support/TargetRegistry.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
LLVMState(const std::string & Triple,const std::string & CpuName,const std::string & Features)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
LLVMState(const std::string & CpuName)50 LLVMState::LLVMState(const std::string &CpuName)
51 : LLVMState(sys::getProcessTriple(),
52 CpuName.empty() ? sys::getHostCPUName().str() : CpuName, "") {}
53
createTargetMachine() const54 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
canAssemble(const MCInst & Inst) const63 bool LLVMState::canAssemble(const MCInst &Inst) const {
64 MCObjectFileInfo ObjectFileInfo;
65 MCContext Context(TheTargetMachine->getMCAsmInfo(),
66 TheTargetMachine->getMCRegisterInfo(), &ObjectFileInfo);
67 std::unique_ptr<const MCCodeEmitter> CodeEmitter(
68 TheTargetMachine->getTarget().createMCCodeEmitter(
69 *TheTargetMachine->getMCInstrInfo(), *TheTargetMachine->getMCRegisterInfo(),
70 Context));
71 assert(CodeEmitter && "unable to create code emitter");
72 SmallVector<char, 16> Tmp;
73 raw_svector_ostream OS(Tmp);
74 SmallVector<MCFixup, 4> Fixups;
75 CodeEmitter->encodeInstruction(Inst, OS, Fixups,
76 *TheTargetMachine->getMCSubtargetInfo());
77 return Tmp.size() > 0;
78 }
79
80 } // namespace exegesis
81 } // namespace llvm
82