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Diffstat (limited to 'lib/ExecutionEngine/TargetSelect.cpp')
-rw-r--r-- | lib/ExecutionEngine/TargetSelect.cpp | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/lib/ExecutionEngine/TargetSelect.cpp b/lib/ExecutionEngine/TargetSelect.cpp new file mode 100644 index 0000000..fa5bcd7 --- /dev/null +++ b/lib/ExecutionEngine/TargetSelect.cpp @@ -0,0 +1,91 @@ +//===-- 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 JIT to use, and allows +// the user to specify a specific one on the commandline with -march=x. Clients +// should initialize targets prior to calling createJIT. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ExecutionEngine/ExecutionEngine.h" +#include "llvm/Module.h" +#include "llvm/ADT/Triple.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Support/Host.h" +#include "llvm/Target/SubtargetFeature.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/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 *ExecutionEngine::selectTarget(Module *Mod, + StringRef MArch, + StringRef MCPU, + const SmallVectorImpl<std::string>& MAttrs, + std::string *ErrorStr) { + Triple TheTriple(Mod->getTargetTriple()); + if (TheTriple.getTriple().empty()) + TheTriple.setTriple(sys::getHostTriple()); + + // 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 + // module/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; + } + } + + if (!TheTarget->hasJIT()) { + errs() << "WARNING: This target JIT is not designed for the host you are" + << " running. If bad things happen, please choose a different " + << "-march switch.\n"; + } + + // Package up features to be passed to target/subtarget + std::string FeaturesStr; + if (!MCPU.empty() || !MAttrs.empty()) { + SubtargetFeatures Features; + Features.setCPU(MCPU); + for (unsigned i = 0; i != MAttrs.size(); ++i) + Features.AddFeature(MAttrs[i]); + FeaturesStr = Features.getString(); + } + + // Allocate a target... + TargetMachine *Target = + TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr); + assert(Target && "Could not allocate target machine!"); + return Target; +} |