Move TargetRegistry and TargetSelect from Target to Support where they belong.

[oota-llvm.git] / lib / Support / TargetRegistry.cpp

diff --git a/lib/Support/TargetRegistry.cpp b/lib/Support/TargetRegistry.cpp
new file mode 100644 (file)
index 0000000..7497bfe
--- /dev/null
+++ b/lib/Support/TargetRegistry.cpp
@@ -0,0 +1,122 @@
+//===--- TargetRegistry.cpp - Target registration -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Host.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cassert>
+#include <vector>
+using namespace llvm;
+
+// Clients are responsible for avoid race conditions in registration.
+static Target *FirstTarget = 0;
+
+TargetRegistry::iterator TargetRegistry::begin() {
+  return iterator(FirstTarget);
+}
+
+const Target *TargetRegistry::lookupTarget(const std::string &TT,
+                                           std::string &Error) {
+  // Provide special warning when no targets are initialized.
+  if (begin() == end()) {
+    Error = "Unable to find target for this triple (no targets are registered)";
+    return 0;
+  }
+  const Target *Best = 0, *EquallyBest = 0;
+  unsigned BestQuality = 0;
+  for (iterator it = begin(), ie = end(); it != ie; ++it) {
+    if (unsigned Qual = it->TripleMatchQualityFn(TT)) {
+      if (!Best || Qual > BestQuality) {
+        Best = &*it;
+        EquallyBest = 0;
+        BestQuality = Qual;
+      } else if (Qual == BestQuality)
+        EquallyBest = &*it;
+    }
+  }
+
+  if (!Best) {
+    Error = "No available targets are compatible with this triple, "
+      "see -version for the available targets.";
+    return 0;
+  }
+
+  // Otherwise, take the best target, but make sure we don't have two equally
+  // good best targets.
+  if (EquallyBest) {
+    Error = std::string("Cannot choose between targets \"") +
+      Best->Name  + "\" and \"" + EquallyBest->Name + "\"";
+    return 0;
+  }
+
+  return Best;
+}
+
+void TargetRegistry::RegisterTarget(Target &T,
+                                    const char *Name,
+                                    const char *ShortDesc,
+                                    Target::TripleMatchQualityFnTy TQualityFn,
+                                    bool HasJIT) {
+  assert(Name && ShortDesc && TQualityFn &&
+         "Missing required target information!");
+
+  // Check if this target has already been initialized, we allow this as a
+  // convenience to some clients.
+  if (T.Name)
+    return;
+         
+  // Add to the list of targets.
+  T.Next = FirstTarget;
+  FirstTarget = &T;
+
+  T.Name = Name;
+  T.ShortDesc = ShortDesc;
+  T.TripleMatchQualityFn = TQualityFn;
+  T.HasJIT = HasJIT;
+}
+
+const Target *TargetRegistry::getClosestTargetForJIT(std::string &Error) {
+  const Target *TheTarget = lookupTarget(sys::getHostTriple(), Error);
+
+  if (TheTarget && !TheTarget->hasJIT()) {
+    Error = "No JIT compatible target available for this host";
+    return 0;
+  }
+
+  return TheTarget;
+}
+
+static int TargetArraySortFn(const void *LHS, const void *RHS) {
+  typedef std::pair<StringRef, const Target*> pair_ty;
+  return ((const pair_ty*)LHS)->first.compare(((const pair_ty*)RHS)->first);
+}
+
+void TargetRegistry::printRegisteredTargetsForVersion() {
+  std::vector<std::pair<StringRef, const Target*> > Targets;
+  size_t Width = 0;
+  for (TargetRegistry::iterator I = TargetRegistry::begin(),
+       E = TargetRegistry::end();
+       I != E; ++I) {
+    Targets.push_back(std::make_pair(I->getName(), &*I));
+    Width = std::max(Width, Targets.back().first.size());
+  }
+  array_pod_sort(Targets.begin(), Targets.end(), TargetArraySortFn);
+
+  raw_ostream &OS = outs();
+  OS << "  Registered Targets:\n";
+  for (unsigned i = 0, e = Targets.size(); i != e; ++i) {
+    OS << "    " << Targets[i].first;
+    OS.indent(Width - Targets[i].first.size()) << " - "
+      << Targets[i].second->getShortDescription() << '\n';
+  }
+  if (Targets.empty())
+    OS << "    (none)\n";
+}