llvm/lib/ExecutionEngine/TargetSelect.cpp
Eric Christopher aa5b9c0f6f Temporarily Revert "Nuke the old JIT." as it's not quite ready to
be deleted. This will be reapplied as soon as possible and before
the 3.6 branch date at any rate.

Approved by Jim Grosbach, Lang Hames, Rafael Espindola.

This reverts commits r215111, 215115, 215116, 215117, 215136.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215154 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 22:02:54 +00:00

108 lines
3.7 KiB
C++

//===-- 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/IR/Module.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
TargetMachine *EngineBuilder::selectTarget() {
Triple TT;
// MCJIT can generate code for remote targets, but the old JIT and Interpreter
// must use the host architecture.
if (UseMCJIT && WhichEngine != EngineKind::Interpreter && M)
TT.setTriple(M->getTargetTriple());
return selectTarget(TT, MArch, MCPU, MAttrs);
}
/// 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) {
Triple TheTriple(TargetTriple);
if (TheTriple.getTriple().empty())
TheTriple.setTriple(sys::getProcessTriple());
// Adjust the triple to match what the user requested.
const Target *TheTarget = nullptr;
if (!MArch.empty()) {
for (TargetRegistry::iterator it = TargetRegistry::begin(),
ie = TargetRegistry::end(); it != ie; ++it) {
if (MArch == it->getName()) {
TheTarget = &*it;
break;
}
}
if (!TheTarget) {
if (ErrorStr)
*ErrorStr = "No available targets are compatible with this -march, "
"see -version for the available targets.\n";
return nullptr;
}
// 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) {
if (ErrorStr)
*ErrorStr = Error;
return nullptr;
}
}
// 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();
}
// FIXME: non-iOS ARM FastISel is broken with MCJIT.
if (UseMCJIT &&
TheTriple.getArch() == Triple::arm &&
!TheTriple.isiOS() &&
OptLevel == CodeGenOpt::None) {
OptLevel = CodeGenOpt::Less;
}
// Allocate a target...
TargetMachine *Target = TheTarget->createTargetMachine(TheTriple.getTriple(),
MCPU, FeaturesStr,
Options,
RelocModel, CMModel,
OptLevel);
assert(Target && "Could not allocate target machine!");
return Target;
}