llvm-6502/lib/ExecutionEngine/JIT/TargetSelect.cpp

94 lines
2.9 KiB
C++
Raw Normal View History

//===-- TargetSelect.cpp - Target Chooser Code ----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the hideously gross code that is currently used to select
// a particular TargetMachine for the JIT to use. This should obviously be
// improved in the future, probably by having the TargetMachines register
// themselves with the runtime, and then have them choose themselves if they
// match the current machine.
//
//===----------------------------------------------------------------------===//
#include "JIT.h"
#include "llvm/Module.h"
#include "llvm/ModuleProvider.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetMachineImpls.h"
#include "Support/CommandLine.h"
using namespace llvm;
#if !defined(ENABLE_X86_JIT) && !defined(ENABLE_SPARC_JIT)
#define NO_JITS_ENABLED
#endif
namespace {
enum ArchName { x86, SparcV9 };
#ifndef NO_JITS_ENABLED
cl::opt<ArchName>
Arch("march", cl::desc("Architecture to JIT to:"), cl::Prefix,
cl::values(
#ifdef ENABLE_X86_JIT
clEnumVal(x86, " IA-32 (Pentium and above)"),
#endif
#ifdef ENABLE_SPARC_JIT
clEnumValN(SparcV9, "sparcv9", " Sparc-V9"),
#endif
0),
#if defined(ENABLE_X86_JIT)
cl::init(x86)
#elif defined(ENABLE_SPARC_JIT)
cl::init(SparcV9)
#endif
);
#endif /* NO_JITS_ENABLED */
}
/// create - Create an return a new JIT compiler if there is one available
/// for the current target. Otherwise, return null.
///
ExecutionEngine *JIT::create(ModuleProvider *MP, IntrinsicLowering *IL) {
TargetMachine* (*TargetMachineAllocator)(const Module &,
IntrinsicLowering *IL) = 0;
// Allow a command-line switch to override what *should* be the default target
// machine for this platform. This allows for debugging a Sparc JIT on X86 --
// our X86 machines are much faster at recompiling LLVM and linking LLI.
#ifndef NO_JITS_ENABLED
switch (Arch) {
#ifdef ENABLE_X86_JIT
case x86:
TargetMachineAllocator = allocateX86TargetMachine;
break;
#endif
#ifdef ENABLE_SPARC_JIT
case SparcV9:
TargetMachineAllocator = allocateSparcV9TargetMachine;
break;
#endif
default:
assert(0 && "-march flag not supported on this host!");
}
#else
return 0;
#endif
// Allocate a target...
TargetMachine *Target = TargetMachineAllocator(*MP->getModule(), IL);
assert(Target && "Could not allocate target machine!");
// If the target supports JIT code generation, return a new JIT now.
if (TargetJITInfo *TJ = Target->getJITInfo())
return new JIT(MP, *Target, *TJ);
return 0;
}