1 files changed, 280 insertions, 0 deletions
diff --git a/contrib/llvm/lib/MC/SubtargetFeature.cpp b/contrib/llvm/lib/MC/SubtargetFeature.cpp
new file mode 100644
index 000000000000..b69af24b531e
--- /dev/null
+++ b/contrib/llvm/lib/MC/SubtargetFeature.cpp
@@ -0,0 +1,280 @@
+//===- SubtargetFeature.cpp - CPU characteristics Implementation ----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file Implements the SubtargetFeature interface.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/SubtargetFeature.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/Config/llvm-config.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <cstddef>
+#include <cstring>
+#include <iterator>
+#include <string>
+#include <vector>
+
+using namespace llvm;
+
+/// Determine if a feature has a flag; '+' or '-'
+static inline bool hasFlag(StringRef Feature) {
+  assert(!Feature.empty() && "Empty string");
+  // Get first character
+  char Ch = Feature[0];
+  // Check if first character is '+' or '-' flag
+  return Ch == '+' || Ch =='-';
+}
+
+/// Return string stripped of flag.
+static inline std::string StripFlag(StringRef Feature) {
+  return hasFlag(Feature) ? Feature.substr(1) : Feature;
+}
+
+/// Return true if enable flag; '+'.
+static inline bool isEnabled(StringRef Feature) {
+  assert(!Feature.empty() && "Empty string");
+  // Get first character
+  char Ch = Feature[0];
+  // Check if first character is '+' for enabled
+  return Ch == '+';
+}
+
+/// Splits a string of comma separated items in to a vector of strings.
+static void Split(std::vector<std::string> &V, StringRef S) {
+  SmallVector<StringRef, 3> Tmp;
+  S.split(Tmp, ',', -1, false /* KeepEmpty */);
+  V.assign(Tmp.begin(), Tmp.end());
+}
+
+void SubtargetFeatures::AddFeature(StringRef String, bool Enable) {
+  // Don't add empty features.
+  if (!String.empty())
+    // Convert to lowercase, prepend flag if we don't already have a flag.
+    Features.push_back(hasFlag(String) ? String.lower()
+                                       : (Enable ? "+" : "-") + String.lower());
+}
+
+/// Find KV in array using binary search.
+static const SubtargetFeatureKV *Find(StringRef S,
+                                      ArrayRef<SubtargetFeatureKV> A) {
+  // Binary search the array
+  auto F = std::lower_bound(A.begin(), A.end(), S);
+  // If not found then return NULL
+  if (F == A.end() || StringRef(F->Key) != S) return nullptr;
+  // Return the found array item
+  return F;
+}
+
+/// Return the length of the longest entry in the table.
+static size_t getLongestEntryLength(ArrayRef<SubtargetFeatureKV> Table) {
+  size_t MaxLen = 0;
+  for (auto &I : Table)
+    MaxLen = std::max(MaxLen, std::strlen(I.Key));
+  return MaxLen;
+}
+
+/// Display help for feature choices.
+static void Help(ArrayRef<SubtargetFeatureKV> CPUTable,
+                 ArrayRef<SubtargetFeatureKV> FeatTable) {
+  // Determine the length of the longest CPU and Feature entries.
+  unsigned MaxCPULen  = getLongestEntryLength(CPUTable);
+  unsigned MaxFeatLen = getLongestEntryLength(FeatTable);
+
+  // Print the CPU table.
+  errs() << "Available CPUs for this target:\n\n";
+  for (auto &CPU : CPUTable)
+    errs() << format("  %-*s - %s.\n", MaxCPULen, CPU.Key, CPU.Desc);
+  errs() << '\n';
+
+  // Print the Feature table.
+  errs() << "Available features for this target:\n\n";
+  for (auto &Feature : FeatTable)
+    errs() << format("  %-*s - %s.\n", MaxFeatLen, Feature.Key, Feature.Desc);
+  errs() << '\n';
+
+  errs() << "Use +feature to enable a feature, or -feature to disable it.\n"
+            "For example, llc -mcpu=mycpu -mattr=+feature1,-feature2\n";
+}
+
+SubtargetFeatures::SubtargetFeatures(StringRef Initial) {
+  // Break up string into separate features
+  Split(Features, Initial);
+}
+
+std::string SubtargetFeatures::getString() const {
+  return join(Features.begin(), Features.end(), ",");
+}
+
+/// For each feature that is (transitively) implied by this feature, set it.
+static
+void SetImpliedBits(FeatureBitset &Bits, const SubtargetFeatureKV &FeatureEntry,
+                    ArrayRef<SubtargetFeatureKV> FeatureTable) {
+  for (const SubtargetFeatureKV &FE : FeatureTable) {
+    if (FeatureEntry.Value == FE.Value) continue;
+
+    if ((FeatureEntry.Implies & FE.Value).any()) {
+      Bits |= FE.Value;
+      SetImpliedBits(Bits, FE, FeatureTable);
+    }
+  }
+}
+
+/// For each feature that (transitively) implies this feature, clear it.
+static
+void ClearImpliedBits(FeatureBitset &Bits,
+                      const SubtargetFeatureKV &FeatureEntry,
+                      ArrayRef<SubtargetFeatureKV> FeatureTable) {
+  for (const SubtargetFeatureKV &FE : FeatureTable) {
+    if (FeatureEntry.Value == FE.Value) continue;
+
+    if ((FE.Implies & FeatureEntry.Value).any()) {
+      Bits &= ~FE.Value;
+      ClearImpliedBits(Bits, FE, FeatureTable);
+    }
+  }
+}
+
+void
+SubtargetFeatures::ToggleFeature(FeatureBitset &Bits, StringRef Feature,
+                                 ArrayRef<SubtargetFeatureKV> FeatureTable) {
+  // Find feature in table.
+  const SubtargetFeatureKV *FeatureEntry =
+      Find(StripFlag(Feature), FeatureTable);
+  // If there is a match
+  if (FeatureEntry) {
+    if ((Bits & FeatureEntry->Value) == FeatureEntry->Value) {
+      Bits &= ~FeatureEntry->Value;
+      // For each feature that implies this, clear it.
+      ClearImpliedBits(Bits, *FeatureEntry, FeatureTable);
+    } else {
+      Bits |=  FeatureEntry->Value;
+
+      // For each feature that this implies, set it.
+      SetImpliedBits(Bits, *FeatureEntry, FeatureTable);
+    }
+  } else {
+    errs() << "'" << Feature << "' is not a recognized feature for this target"
+           << " (ignoring feature)\n";
+  }
+}
+
+void SubtargetFeatures::ApplyFeatureFlag(FeatureBitset &Bits, StringRef Feature,
+                                    ArrayRef<SubtargetFeatureKV> FeatureTable) {
+  assert(hasFlag(Feature));
+
+  // Find feature in table.
+  const SubtargetFeatureKV *FeatureEntry =
+      Find(StripFlag(Feature), FeatureTable);
+  // If there is a match
+  if (FeatureEntry) {
+    // Enable/disable feature in bits
+    if (isEnabled(Feature)) {
+      Bits |= FeatureEntry->Value;
+
+      // For each feature that this implies, set it.
+      SetImpliedBits(Bits, *FeatureEntry, FeatureTable);
+    } else {
+      Bits &= ~FeatureEntry->Value;
+
+      // For each feature that implies this, clear it.
+      ClearImpliedBits(Bits, *FeatureEntry, FeatureTable);
+    }
+  } else {
+    errs() << "'" << Feature << "' is not a recognized feature for this target"
+           << " (ignoring feature)\n";
+  }
+}
+
+FeatureBitset
+SubtargetFeatures::getFeatureBits(StringRef CPU,
+                                  ArrayRef<SubtargetFeatureKV> CPUTable,
+                                  ArrayRef<SubtargetFeatureKV> FeatureTable) {
+  if (CPUTable.empty() || FeatureTable.empty())
+    return FeatureBitset();
+
+  assert(std::is_sorted(std::begin(CPUTable), std::end(CPUTable)) &&
+         "CPU table is not sorted");
+  assert(std::is_sorted(std::begin(FeatureTable), std::end(FeatureTable)) &&
+         "CPU features table is not sorted");
+  // Resulting bits
+  FeatureBitset Bits;
+
+  // Check if help is needed
+  if (CPU == "help")
+    Help(CPUTable, FeatureTable);
+
+  // Find CPU entry if CPU name is specified.
+  else if (!CPU.empty()) {
+    const SubtargetFeatureKV *CPUEntry = Find(CPU, CPUTable);
+
+    // If there is a match
+    if (CPUEntry) {
+      // Set base feature bits
+      Bits = CPUEntry->Value;
+
+      // Set the feature implied by this CPU feature, if any.
+      for (auto &FE : FeatureTable) {
+        if ((CPUEntry->Value & FE.Value).any())
+          SetImpliedBits(Bits, FE, FeatureTable);
+      }
+    } else {
+      errs() << "'" << CPU << "' is not a recognized processor for this target"
+             << " (ignoring processor)\n";
+    }
+  }
+
+  // Iterate through each feature
+  for (const std::string &Feature : Features) {
+    // Check for help
+    if (Feature == "+help")
+      Help(CPUTable, FeatureTable);
+
+    ApplyFeatureFlag(Bits, Feature, FeatureTable);
+  }
+
+  return Bits;
+}
+
+void SubtargetFeatures::print(raw_ostream &OS) const {
+  for (auto &F : Features)
+    OS << F << " ";
+  OS << "\n";
+}
+
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+LLVM_DUMP_METHOD void SubtargetFeatures::dump() const {
+  print(dbgs());
+}
+#endif
+
+void SubtargetFeatures::getDefaultSubtargetFeatures(const Triple& Triple) {
+  // FIXME: This is an inelegant way of specifying the features of a
+  // subtarget. It would be better if we could encode this information
+  // into the IR. See <rdar://5972456>.
+  if (Triple.getVendor() == Triple::Apple) {
+    if (Triple.getArch() == Triple::ppc) {
+      // powerpc-apple-*
+      AddFeature("altivec");
+    } else if (Triple.getArch() == Triple::ppc64) {
+      // powerpc64-apple-*
+      AddFeature("64bit");
+      AddFeature("altivec");
+    }
+  }
+}