New feature: add support for target intrinsics being defined in the

[oota-llvm.git] / lib / Target / TargetMachineRegistry.cpp

diff --git a/lib/Target/TargetMachineRegistry.cpp b/lib/Target/TargetMachineRegistry.cpp
index f5286efaab3a6642c47bba59665e6a9b803fb28f..c1a4777c63140304bbc2b412e877d967697e5b2f 100644 (file)
--- a/lib/Target/TargetMachineRegistry.cpp
+++ b/lib/Target/TargetMachineRegistry.cpp
@@ -1,10 +1,10 @@
 //===-- TargetMachineRegistry.cpp - Target Auto Registration Impl ---------===//
-// 
+//
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-// 
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
 //===----------------------------------------------------------------------===//
 //
 // This file exposes the RegisterTarget class, which TargetMachine
@@ -15,7 +15,64 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Target/TargetMachineRegistry.h"
+#include <algorithm>
 using namespace llvm;
 
-const TargetMachineRegistry::Entry *TargetMachineRegistry::List = 0;
+/// getClosestStaticTargetForModule - Given an LLVM module, pick the best target
+/// that is compatible with the module.  If no close target can be found, this
+/// returns null and sets the Error string to a reason.
+const TargetMachineRegistry::entry *
+TargetMachineRegistry::getClosestStaticTargetForModule(const Module &M,
+                                                       std::string &Error) {
+  std::vector<std::pair<unsigned, const entry *> > UsableTargets;
+  for (Registry<TargetMachine>::iterator I = begin(), E = end(); I != E; ++I)
+    if (unsigned Qual = I->ModuleMatchQualityFn(M))
+      UsableTargets.push_back(std::make_pair(Qual, &*I));
+
+  if (UsableTargets.empty()) {
+    Error = "No available targets are compatible with this module";
+    return 0;
+  } else if (UsableTargets.size() == 1)
+    return UsableTargets.back().second;
+
+  // Otherwise, take the best target, but make sure we don't have two equally
+  // good best targets.
+  std::sort(UsableTargets.begin(), UsableTargets.end());
+  if (UsableTargets.back().first ==UsableTargets[UsableTargets.size()-2].first){
+    Error = "Cannot choose between targets \"" +
+      std::string(UsableTargets.back().second->Name) + "\" and \"" +
+      std::string(UsableTargets[UsableTargets.size()-2].second->Name) + "\"";
+    return 0;
+  }
+  return UsableTargets.back().second;
+}
+
+/// getClosestTargetForJIT - Pick the best target that is compatible with
+/// the current host.  If no close target can be found, this returns null
+/// and sets the Error string to a reason.
+const TargetMachineRegistry::entry *
+TargetMachineRegistry::getClosestTargetForJIT(std::string &Error) {
+  std::vector<std::pair<unsigned, const entry *> > UsableTargets;
+  for (Registry<TargetMachine>::iterator I = begin(), E = end(); I != E; ++I)
+    if (unsigned Qual = I->JITMatchQualityFn())
+      UsableTargets.push_back(std::make_pair(Qual, &*I));
+
+  if (UsableTargets.empty()) {
+    Error = "No JIT is available for this host";
+    return 0;
+  } else if (UsableTargets.size() == 1)
+    return UsableTargets.back().second;
+
+  // Otherwise, take the best target.  If there is a tie, just pick one.
+  unsigned MaxQual = UsableTargets.front().first;
+  const entry *MaxQualTarget = UsableTargets.front().second;
+
+  for (unsigned i = 1, e = UsableTargets.size(); i != e; ++i)
+    if (UsableTargets[i].first > MaxQual) {
+      MaxQual = UsableTargets[i].first;
+      MaxQualTarget = UsableTargets[i].second;
+    }
+
+  return MaxQualTarget;
+}