- Added MCSubtargetInfo to capture subtarget features and scheduling

itineraries.
- Refactor TargetSubtarget to be based on MCSubtargetInfo.
- Change tablegen generated subtarget info to initialize MCSubtargetInfo
  and hide more details from targets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134257 91177308-0d34-0410-b5e6-96231b3b80d8

lib/MC/MCSubtargetInfo.cpp

@@ -0,0 +1,44 @@
+//===-- MCSubtargetInfo.cpp - Subtarget Information -----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/MC/MCInstrItineraries.h"
+#include "llvm/MC/SubtargetFeature.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+
+using namespace llvm;
+
+InstrItineraryData
+MCSubtargetInfo::getInstrItineraryForCPU(StringRef CPU) const {
+  assert(ProcItins && "Instruction itineraries information not available!");
+
+#ifndef NDEBUG
+  for (size_t i = 1; i < NumProcs; i++) {
+    assert(strcmp(ProcItins[i - 1].Key, ProcItins[i].Key) < 0 &&
+           "Itineraries table is not sorted");
+  }
+#endif
+
+  // Find entry
+  SubtargetInfoKV KV;
+  KV.Key = CPU.data();
+  const SubtargetInfoKV *Found =
+    std::lower_bound(ProcItins, ProcItins+NumProcs, KV);
+  if (Found == ProcItins+NumProcs || StringRef(Found->Key) != CPU) {
+    errs() << "'" << CPU
+           << "' is not a recognized processor for this target"
+           << " (ignoring processor)\n";
+    return InstrItineraryData();
+  }
+
+  return InstrItineraryData(Stages, OperandCycles, ForwardingPathes,
+                            (InstrItinerary *)Found->Value);
+}