I'm introducing a new machine model to simultaneously allow simple
subtarget CPU descriptions and support new features of
MachineScheduler.

MachineModel has three categories of data:
1) Basic properties for coarse grained instruction cost model.
2) Scheduler Read/Write resources for simple per-opcode and operand cost model (TBD).
3) Instruction itineraties for detailed per-cycle reservation tables.

These will all live side-by-side. Any subtarget can use any
combination of them. Instruction itineraries will not change in the
near term. In the long run, I expect them to only be relevant for
in-order VLIW machines that have complex contraints and require a
precise scheduling/bundling model. Once itineraries are only actively
used by VLIW-ish targets, they could be replaced by something more
appropriate for those targets.

This tablegen backend rewrite sets things up for introducing
MachineModel type #2: per opcode/operand cost model.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159891 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/CodeGenTarget.cpp b/utils/TableGen/CodeGenTarget.cpp
index 4bc4c54..1dd2efc 100644
--- a/utils/TableGen/CodeGenTarget.cpp
+++ b/utils/TableGen/CodeGenTarget.cpp
@@ -16,6 +16,7 @@
 
 #include "CodeGenTarget.h"
 #include "CodeGenIntrinsics.h"
+#include "CodeGenSchedule.h"
 #include "llvm/TableGen/Record.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/STLExtras.h"
@@ -112,7 +113,7 @@
 /// getTarget - Return the current instance of the Target class.
 ///
 CodeGenTarget::CodeGenTarget(RecordKeeper &records)
-  : Records(records), RegBank(0) {
+  : Records(records), RegBank(0), SchedModels(0) {
   std::vector<Record*> Targets = Records.getAllDerivedDefinitions("Target");
   if (Targets.size() == 0)
     throw std::string("ERROR: No 'Target' subclasses defined!");
@@ -121,6 +122,10 @@
   TargetRec = Targets[0];
 }
 
+CodeGenTarget::~CodeGenTarget() {
+  delete RegBank;
+  delete SchedModels;
+}
 
 const std::string &CodeGenTarget::getName() const {
   return TargetRec->getName();
@@ -235,6 +240,11 @@
                         LegalValueTypes.end());
 }
 
+CodeGenSchedModels &CodeGenTarget::getSchedModels() const {
+  if (!SchedModels)
+    SchedModels = new CodeGenSchedModels(Records, *this);
+  return *SchedModels;
+}
 
 void CodeGenTarget::ReadInstructions() const {
   std::vector<Record*> Insts = Records.getAllDerivedDefinitions("Instruction");