llvm-project

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//===- SubtargetFeature.cpp - CPU characteristics Implementation ----------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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/// \file Implements the SubtargetFeature interface.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/TargetParser/SubtargetFeature.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/StringExtras.h"
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#include "llvm/ADT/StringRef.h"
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#include "llvm/Config/llvm-config.h"
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#include "llvm/Support/Compiler.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/TargetParser/Triple.h"
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#include <algorithm>
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#include <string>
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#include <vector>
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using namespace llvm;
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/// Splits a string of comma separated items in to a vector of strings.
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void SubtargetFeatures::Split(std::vector<std::string> &V, StringRef S) {
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  SmallVector<StringRef, 3> Tmp;
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  S.split(Tmp, ',', -1, false /* KeepEmpty */);
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  V.reserve(Tmp.size());
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  for (StringRef T : Tmp)
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    V.push_back(std::string(T));
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}
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void SubtargetFeatures::AddFeature(StringRef String, bool Enable) {
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  // Don't add empty features.
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  if (!String.empty())
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    // Convert to lowercase, prepend flag if we don't already have a flag.
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    Features.push_back(hasFlag(String) ? String.lower()
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                                       : (Enable ? "+" : "-") + String.lower());
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}
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void SubtargetFeatures::addFeaturesVector(
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    const ArrayRef<std::string> OtherFeatures) {
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  Features.insert(Features.cend(), OtherFeatures.begin(), OtherFeatures.end());
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}
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SubtargetFeatures::SubtargetFeatures(StringRef Initial) {
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  // Break up string into separate features
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  Split(Features, Initial);
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}
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std::string SubtargetFeatures::getString() const {
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  return join(Features.begin(), Features.end(), ",");
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}
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void SubtargetFeatures::print(raw_ostream &OS) const {
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  for (const auto &F : Features)
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    OS << F << " ";
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  OS << "\n";
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}
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#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
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LLVM_DUMP_METHOD void SubtargetFeatures::dump() const {
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  print(dbgs());
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}
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#endif
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void SubtargetFeatures::getDefaultSubtargetFeatures(const Triple& Triple) {
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  // FIXME: This is an inelegant way of specifying the features of a
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  // subtarget. It would be better if we could encode this information
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  // into the IR.
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  if (Triple.getVendor() == Triple::Apple) {
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    if (Triple.getArch() == Triple::ppc) {
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      // powerpc-apple-*
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      AddFeature("altivec");
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    } else if (Triple.getArch() == Triple::ppc64) {
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      // powerpc64-apple-*
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      AddFeature("64bit");
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      AddFeature("altivec");
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    }
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  }
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}
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