llvm-6502/lib/ExecutionEngine/TargetSelect.cpp
Dylan Noblesmith 9ea47179e6 ExecutionEngine: refactor interface
The OptLevel is now redundant with the TargetMachine*.
And selectTarget() isn't really JIT-specific and could probably
get refactored into one of the lower level libraries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146355 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-12 04:20:36 +00:00

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3.3 KiB
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//===-- TargetSelect.cpp - Target Chooser Code ----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This just asks the TargetRegistry for the appropriate target to use, and
// allows the user to specify a specific one on the commandline with -march=x,
// -mcpu=y, and -mattr=a,-b,+c. Clients should initialize targets prior to
// calling selectTarget().
//
//===----------------------------------------------------------------------===//
#include "llvm/ExecutionEngine/ExecutionEngine.h"
#include "llvm/ADT/Triple.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/TargetRegistry.h"
using namespace llvm;
/// selectTarget - Pick a target either via -march or by guessing the native
/// arch. Add any CPU features specified via -mcpu or -mattr.
TargetMachine *EngineBuilder::selectTarget(const Triple &TargetTriple,
StringRef MArch,
StringRef MCPU,
const SmallVectorImpl<std::string>& MAttrs,
const TargetOptions &Options,
Reloc::Model RM,
CodeModel::Model CM,
CodeGenOpt::Level OL,
std::string *ErrorStr) {
Triple TheTriple(TargetTriple);
if (TheTriple.getTriple().empty())
TheTriple.setTriple(sys::getDefaultTargetTriple());
// Adjust the triple to match what the user requested.
const Target *TheTarget = 0;
if (!MArch.empty()) {
for (TargetRegistry::iterator it = TargetRegistry::begin(),
ie = TargetRegistry::end(); it != ie; ++it) {
if (MArch == it->getName()) {
TheTarget = &*it;
break;
}
}
if (!TheTarget) {
*ErrorStr = "No available targets are compatible with this -march, "
"see -version for the available targets.\n";
return 0;
}
// Adjust the triple to match (if known), otherwise stick with the
// requested/host triple.
Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
if (Type != Triple::UnknownArch)
TheTriple.setArch(Type);
} else {
std::string Error;
TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Error);
if (TheTarget == 0) {
if (ErrorStr)
*ErrorStr = Error;
return 0;
}
}
// Package up features to be passed to target/subtarget
std::string FeaturesStr;
if (!MAttrs.empty()) {
SubtargetFeatures Features;
for (unsigned i = 0; i != MAttrs.size(); ++i)
Features.AddFeature(MAttrs[i]);
FeaturesStr = Features.getString();
}
// Allocate a target...
TargetMachine *Target = TheTarget->createTargetMachine(TheTriple.getTriple(),
MCPU, FeaturesStr,
Options,
RM, CM, OL);
assert(Target && "Could not allocate target machine!");
return Target;
}