1 files changed, 308 insertions, 0 deletions
diff --git a/clang/lib/Driver/Multilib.cpp b/clang/lib/Driver/Multilib.cpp
new file mode 100644
index 000000000000..303047e05f78
--- /dev/null
+++ b/clang/lib/Driver/Multilib.cpp
@@ -0,0 +1,308 @@
+//===- Multilib.cpp - Multilib Implementation -----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Driver/Multilib.h"
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/Regex.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <string>
+
+using namespace clang;
+using namespace driver;
+using namespace llvm::sys;
+
+/// normalize Segment to "/foo/bar" or "".
+static void normalizePathSegment(std::string &Segment) {
+  StringRef seg = Segment;
+
+  // Prune trailing "/" or "./"
+  while (true) {
+    StringRef last = path::filename(seg);
+    if (last != ".")
+      break;
+    seg = path::parent_path(seg);
+  }
+
+  if (seg.empty() || seg == "/") {
+    Segment.clear();
+    return;
+  }
+
+  // Add leading '/'
+  if (seg.front() != '/') {
+    Segment = "/" + seg.str();
+  } else {
+    Segment = seg;
+  }
+}
+
+Multilib::Multilib(StringRef GCCSuffix, StringRef OSSuffix,
+                   StringRef IncludeSuffix, int Priority)
+    : GCCSuffix(GCCSuffix), OSSuffix(OSSuffix), IncludeSuffix(IncludeSuffix),
+      Priority(Priority) {
+  normalizePathSegment(this->GCCSuffix);
+  normalizePathSegment(this->OSSuffix);
+  normalizePathSegment(this->IncludeSuffix);
+}
+
+Multilib &Multilib::gccSuffix(StringRef S) {
+  GCCSuffix = S;
+  normalizePathSegment(GCCSuffix);
+  return *this;
+}
+
+Multilib &Multilib::osSuffix(StringRef S) {
+  OSSuffix = S;
+  normalizePathSegment(OSSuffix);
+  return *this;
+}
+
+Multilib &Multilib::includeSuffix(StringRef S) {
+  IncludeSuffix = S;
+  normalizePathSegment(IncludeSuffix);
+  return *this;
+}
+
+LLVM_DUMP_METHOD void Multilib::dump() const {
+  print(llvm::errs());
+}
+
+void Multilib::print(raw_ostream &OS) const {
+  assert(GCCSuffix.empty() || (StringRef(GCCSuffix).front() == '/'));
+  if (GCCSuffix.empty())
+    OS << ".";
+  else {
+    OS << StringRef(GCCSuffix).drop_front();
+  }
+  OS << ";";
+  for (StringRef Flag : Flags) {
+    if (Flag.front() == '+')
+      OS << "@" << Flag.substr(1);
+  }
+}
+
+bool Multilib::isValid() const {
+  llvm::StringMap<int> FlagSet;
+  for (unsigned I = 0, N = Flags.size(); I != N; ++I) {
+    StringRef Flag(Flags[I]);
+    llvm::StringMap<int>::iterator SI = FlagSet.find(Flag.substr(1));
+
+    assert(StringRef(Flag).front() == '+' || StringRef(Flag).front() == '-');
+
+    if (SI == FlagSet.end())
+      FlagSet[Flag.substr(1)] = I;
+    else if (Flags[I] != Flags[SI->getValue()])
+      return false;
+  }
+  return true;
+}
+
+bool Multilib::operator==(const Multilib &Other) const {
+  // Check whether the flags sets match
+  // allowing for the match to be order invariant
+  llvm::StringSet<> MyFlags;
+  for (const auto &Flag : Flags)
+    MyFlags.insert(Flag);
+
+  for (const auto &Flag : Other.Flags)
+    if (MyFlags.find(Flag) == MyFlags.end())
+      return false;
+
+  if (osSuffix() != Other.osSuffix())
+    return false;
+
+  if (gccSuffix() != Other.gccSuffix())
+    return false;
+
+  if (includeSuffix() != Other.includeSuffix())
+    return false;
+
+  return true;
+}
+
+raw_ostream &clang::driver::operator<<(raw_ostream &OS, const Multilib &M) {
+  M.print(OS);
+  return OS;
+}
+
+MultilibSet &MultilibSet::Maybe(const Multilib &M) {
+  Multilib Opposite;
+  // Negate any '+' flags
+  for (StringRef Flag : M.flags()) {
+    if (Flag.front() == '+')
+      Opposite.flags().push_back(("-" + Flag.substr(1)).str());
+  }
+  return Either(M, Opposite);
+}
+
+MultilibSet &MultilibSet::Either(const Multilib &M1, const Multilib &M2) {
+  return Either({M1, M2});
+}
+
+MultilibSet &MultilibSet::Either(const Multilib &M1, const Multilib &M2,
+                                 const Multilib &M3) {
+  return Either({M1, M2, M3});
+}
+
+MultilibSet &MultilibSet::Either(const Multilib &M1, const Multilib &M2,
+                                 const Multilib &M3, const Multilib &M4) {
+  return Either({M1, M2, M3, M4});
+}
+
+MultilibSet &MultilibSet::Either(const Multilib &M1, const Multilib &M2,
+                                 const Multilib &M3, const Multilib &M4,
+                                 const Multilib &M5) {
+  return Either({M1, M2, M3, M4, M5});
+}
+
+static Multilib compose(const Multilib &Base, const Multilib &New) {
+  SmallString<128> GCCSuffix;
+  llvm::sys::path::append(GCCSuffix, "/", Base.gccSuffix(), New.gccSuffix());
+  SmallString<128> OSSuffix;
+  llvm::sys::path::append(OSSuffix, "/", Base.osSuffix(), New.osSuffix());
+  SmallString<128> IncludeSuffix;
+  llvm::sys::path::append(IncludeSuffix, "/", Base.includeSuffix(),
+                          New.includeSuffix());
+
+  Multilib Composed(GCCSuffix, OSSuffix, IncludeSuffix);
+
+  Multilib::flags_list &Flags = Composed.flags();
+
+  Flags.insert(Flags.end(), Base.flags().begin(), Base.flags().end());
+  Flags.insert(Flags.end(), New.flags().begin(), New.flags().end());
+
+  return Composed;
+}
+
+MultilibSet &MultilibSet::Either(ArrayRef<Multilib> MultilibSegments) {
+  multilib_list Composed;
+
+  if (Multilibs.empty())
+    Multilibs.insert(Multilibs.end(), MultilibSegments.begin(),
+                     MultilibSegments.end());
+  else {
+    for (const auto &New : MultilibSegments) {
+      for (const auto &Base : *this) {
+        Multilib MO = compose(Base, New);
+        if (MO.isValid())
+          Composed.push_back(MO);
+      }
+    }
+
+    Multilibs = Composed;
+  }
+
+  return *this;
+}
+
+MultilibSet &MultilibSet::FilterOut(FilterCallback F) {
+  filterInPlace(F, Multilibs);
+  return *this;
+}
+
+MultilibSet &MultilibSet::FilterOut(const char *Regex) {
+  llvm::Regex R(Regex);
+#ifndef NDEBUG
+  std::string Error;
+  if (!R.isValid(Error)) {
+    llvm::errs() << Error;
+    llvm_unreachable("Invalid regex!");
+  }
+#endif
+
+  filterInPlace([&R](const Multilib &M) { return R.match(M.gccSuffix()); },
+                Multilibs);
+  return *this;
+}
+
+void MultilibSet::push_back(const Multilib &M) { Multilibs.push_back(M); }
+
+void MultilibSet::combineWith(const MultilibSet &Other) {
+  Multilibs.insert(Multilibs.end(), Other.begin(), Other.end());
+}
+
+static bool isFlagEnabled(StringRef Flag) {
+  char Indicator = Flag.front();
+  assert(Indicator == '+' || Indicator == '-');
+  return Indicator == '+';
+}
+
+bool MultilibSet::select(const Multilib::flags_list &Flags, Multilib &M) const {
+  llvm::StringMap<bool> FlagSet;
+
+  // Stuff all of the flags into the FlagSet such that a true mappend indicates
+  // the flag was enabled, and a false mappend indicates the flag was disabled.
+  for (StringRef Flag : Flags)
+    FlagSet[Flag.substr(1)] = isFlagEnabled(Flag);
+
+  multilib_list Filtered = filterCopy([&FlagSet](const Multilib &M) {
+    for (StringRef Flag : M.flags()) {
+      llvm::StringMap<bool>::const_iterator SI = FlagSet.find(Flag.substr(1));
+      if (SI != FlagSet.end())
+        if (SI->getValue() != isFlagEnabled(Flag))
+          return true;
+    }
+    return false;
+  }, Multilibs);
+
+  if (Filtered.empty())
+    return false;
+  if (Filtered.size() == 1) {
+    M = Filtered[0];
+    return true;
+  }
+
+  // Sort multilibs by priority and select the one with the highest priority.
+  llvm::sort(Filtered.begin(), Filtered.end(),
+             [](const Multilib &a, const Multilib &b) -> bool {
+               return a.priority() > b.priority();
+             });
+
+  if (Filtered[0].priority() > Filtered[1].priority()) {
+    M = Filtered[0];
+    return true;
+  }
+
+  // TODO: We should consider returning llvm::Error rather than aborting.
+  assert(false && "More than one multilib with the same priority");
+  return false;
+}
+
+LLVM_DUMP_METHOD void MultilibSet::dump() const {
+  print(llvm::errs());
+}
+
+void MultilibSet::print(raw_ostream &OS) const {
+  for (const auto &M : *this)
+    OS << M << "\n";
+}
+
+MultilibSet::multilib_list MultilibSet::filterCopy(FilterCallback F,
+                                                   const multilib_list &Ms) {
+  multilib_list Copy(Ms);
+  filterInPlace(F, Copy);
+  return Copy;
+}
+
+void MultilibSet::filterInPlace(FilterCallback F, multilib_list &Ms) {
+  Ms.erase(std::remove_if(Ms.begin(), Ms.end(), F), Ms.end());
+}
+
+raw_ostream &clang::driver::operator<<(raw_ostream &OS, const MultilibSet &MS) {
+  MS.print(OS);
+  return OS;
+}