Adding the initial implementation of the SlotTable class. This class is

the Abstract Data Type that holds slot number values and associates them
with Type* and Value*. The SlotTable is simply the holder of the slot
numbers and provides a controlled interface for building the table. It does
not enforce any particular idiom or functionality for manipulating the slot
numbers.

This is part of bug_122. The SlotCalculator and SlotMachine classes will
follow.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13764 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 309 insertions, 0 deletions

diff --git a/lib/Bytecode/Writer/SlotTable.cpp b/lib/Bytecode/Writer/SlotTable.cpp
new file mode 100644
index 0000000..56c47b2
--- /dev/null
+++ b/lib/Bytecode/Writer/SlotTable.cpp
@@ -0,0 +1,115 @@
+//===-- SlotCalculator.cpp - Calculate what slots values land in ----------===//
+// 
+//                     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 implements a utility class for keeping track of slot numbers for
+// bytecode and assembly writing.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Internal/SlotTable.h"
+#include "llvm/Type.h"
+#include "llvm/Value.h"
+#include "llvm/GlobalValue.h"
+#include "llvm/Constants.h"
+
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+//                            SlotTable Implementation
+//===----------------------------------------------------------------------===//
+
+SlotTable::SlotTable( bool dont_insert_primitives ) {
+  if ( ! dont_insert_primitives ) 
+    this->insertPrimitives();
+}
+
+// empty - determine if the slot table is completely empty.
+bool SlotTable::empty() const {
+  return vTable.empty() && vMap.empty() && tPlane.empty() && tMap.empty();
+}
+
+// getSlot - get the slot number associated with value Val
+SlotTable::SlotNum SlotTable::getSlot(const Value* Val) const {
+  ValueMap::const_iterator I = vMap.find( Val );
+  if ( I != vMap.end() )
+    return I->second;
+
+  // Do not number ConstantPointerRef's at all.  They are an abomination.
+  if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(Val))
+    return this->getSlot(CPR->getValue());
+
+  return BAD_SLOT;
+}
+
+// getSlot - get the slot number associated with type Typ
+SlotTable::SlotNum SlotTable::getSlot(const Type* Typ) const {
+  TypeMap::const_iterator I = tMap.find( Typ );
+  if ( I != tMap.end() )
+    return I->second;
+
+  return BAD_SLOT;
+}
+
+// clear - completely clear the slot table of all entries
+void SlotTable::clear() {
+  vTable.clear();
+  vMap.clear();
+  tPlane.clear();
+  tMap.clear();
+}
+
+// resize - make sure there's enough room for specific number of planes
+void SlotTable::resize( size_t new_size ) {
+  vTable.resize( new_size );
+}
+
+// insert - insert a Value into a specific plane
+SlotTable::SlotNum SlotTable::insert( const Value* Val, PlaneNum plane ) {
+  if ( vTable.size() <= plane ) // Make sure we have the type plane allocated
+    vTable.resize(plane+1, ValuePlane());
+
+  // Insert node into table and map
+  SlotNum DestSlot = vMap[Val] = vTable[plane].size();
+  vTable[plane].push_back(Val);
+  return DestSlot;
+}
+
+// insert - insert a type into a specific plane
+SlotTable::SlotNum SlotTable::insert( const Type* Typ ) {
+  // Insert node into table and map
+  SlotNum DestSlot = tMap[Typ] = tPlane.size();
+  tPlane.push_back(Typ);
+  return DestSlot;
+}
+
+// remove - remove a value from the slot table
+SlotTable::SlotNum SlotTable::remove( const Value* Val, PlaneNum plane ) {
+  // FIXME: not implemented - not sure we need it
+  return BAD_SLOT;
+}
+
+// remove - remove a type from the slot table
+SlotTable::SlotNum SlotTable::remove( const Type* Typ ) {
+  // FIXME: not implemented - not sure we need it
+  return BAD_SLOT;
+}
+
+// insertPrimitives - insert the primitive types for initialization
+// Make sure that all of the primitive types are in the table
+// and that their Primitive ID is equal to their slot #
+void SlotTable::insertPrimitives() {
+  for (PlaneNum plane = 0; plane < Type::FirstDerivedTyID; ++plane) {
+    const Type* Ty = Type::getPrimitiveType((Type::PrimitiveID) plane);
+    assert(Ty && "Couldn't get primitive type id");
+    SlotNum slot = this->insert(Ty);
+    assert(slot == plane && "Type slot didn't match plane number");
+  }
+}
+
+// vim: sw=2
diff --git a/lib/Bytecode/Writer/SlotTable.h b/lib/Bytecode/Writer/SlotTable.h
new file mode 100644
index 0000000..32402ea
--- /dev/null
+++ b/lib/Bytecode/Writer/SlotTable.h
@@ -0,0 +1,194 @@
+//===-- Internal/SlotTable.h - Type/Value Slot Holder -----------*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This file declares the SlotTable class for type plane numbering.
+// 
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_INTERNAL_SLOTTABLE_H
+#define LLVM_INTERNAL_SLOTTABLE_H
+
+#include <vector>
+#include <map>
+
+namespace llvm {
+
+// Forward declarations
+class Value;
+class Type;
+class Module;
+class Function;
+class SymbolTable;
+class ConstantArray;
+
+/// This class is the common abstract data type for both the SlotMachine and
+/// the SlotCalculator. It provides the two-way mapping between Values and 
+/// Slots as well as the two-way mapping between Types and Slots. For Values,
+/// the slot number can be extracted by simply using the getSlot()
+/// method and passing in the Value. For Types, it is the same. 
+/// @brief Abstract data type for slot numbers.
+class SlotTable
+{
+/// @name Types
+/// @{
+public:
+
+  /// This type is used throughout the code to make it clear that 
+  /// an unsigned value refers to a Slot number and not something else.
+  /// @brief Type slot number identification type.
+  typedef unsigned SlotNum;
+
+  /// This type is used throughout the code to make it clear that an
+  /// unsigned value refers to a type plane number and not something else.
+  /// @brief The type of a plane number (corresponds to Type::PrimitiveID).
+  typedef unsigned PlaneNum;
+
+  /// @brief Some constants used as flags instead of actual slot numbers
+  enum Constants {
+      MAX_SLOT = 4294967294U,
+      BAD_SLOT = 4294967295U
+  };
+
+  /// @brief A single plane of Values. Intended index is slot number.
+  typedef std::vector<const Value*> ValuePlane; 
+
+  /// @brief A table of Values. Intended index is Type::PrimitiveID.
+  typedef std::vector<ValuePlane> ValueTable; 
+
+  /// @brief A map of values to slot numbers.
+  typedef std::map<const Value*,SlotNum> ValueMap; 
+
+  /// @brief A single plane of Types. Intended index is slot number.
+  typedef std::vector<const Type*>  TypePlane;
+
+  /// @brief A map of types to slot numbers.
+  typedef std::map<const Type*,SlotNum> TypeMap;
+
+/// @}
+/// @name Constructors
+/// @{
+public:
+  /// This constructor initializes all the containers in the SlotTable
+  /// to empty and then inserts all the primitive types into the type plane
+  /// by default. This is done as a convenience since most uses of the
+  /// SlotTable will need the primitive types. If you don't need them, pass
+  /// in true.
+  /// @brief Default Constructor
+  SlotTable( 
+      bool dont_insert_primitives = false ///< Control insertion of primitives.
+  );
+
+/// @}
+/// @name Accessors
+/// @{
+public:
+  /// @brief Get the number of planes of values.
+  size_t value_size() const { return vTable.size(); }
+
+  /// @brief Get the number of types.
+  size_t type_size() const { return tPlane.size(); }
+
+  /// @brief Determine if a specific type plane in the value table exists
+  bool plane_exists(PlaneNum plane) const {
+    return vTable.size() > plane;
+  }
+
+  /// @brief Determine if a specific type plane in the value table is empty
+  bool plane_empty(PlaneNum plane) const {
+    return (plane_exists(plane) ? vTable[plane].empty() : true);
+  }
+
+  /// @brief Get the number of entries in a specific plane of the value table
+  size_t plane_size(PlaneNum plane) const {
+    return (plane_exists(plane) ? vTable[plane].size() : 0 );
+  }
+
+  /// @returns true if the slot table is completely empty.
+  /// @brief Determine if the SlotTable is empty.
+  bool empty() const;
+
+  /// @returns the slot number or BAD_SLOT if Val is not in table.
+  /// @brief Get a slot number for a Value.
+  SlotNum getSlot(const Value* Val) const;
+
+  /// @returns the slot number or BAD_SLOT if Type is not in the table.
+  /// @brief Get a slot number for a Type.
+  SlotNum getSlot(const Type* Typ) const;
+
+  /// @returns true iff the Value is in the table.
+  /// @brief Determine if a Value has a slot number.
+  bool hasSlot(const Value* Val) { return getSlot(Val) != BAD_SLOT; }
+
+  /// @returns true iff the Type is in the table.
+  /// @brief Determine if a Type has a slot number.
+  bool hasSlot(const Type* Typ) { return getSlot(Typ) != BAD_SLOT; }
+
+/// @}
+/// @name Mutators
+/// @{
+public:
+  /// @brief Completely clear the SlotTable;
+  void clear();
+
+  /// @brief Resize the table to incorporate at least \p new_size planes
+  void resize( size_t new_size );
+
+  /// @returns the slot number of the newly inserted value in its plane
+  /// @brief Add a Value to the SlotTable
+  SlotNum insert(const Value* Val, PlaneNum plane );
+
+  /// @returns the slot number of the newly inserted type
+  /// @brief Add a Type to the SlotTable
+  SlotNum insert( const Type* Typ );
+
+  /// @returns the slot number that \p Val had when it was in the table
+  /// @brief Remove a Value from the SlotTable
+  SlotNum remove( const Value* Val, PlaneNum plane );
+
+  /// @returns the slot number that \p Typ had when it was in the table
+  /// @brief Remove a Type from the SlotTable
+  SlotNum remove( const Type* Typ );
+
+/// @}
+/// @name Implementation Details
+/// @{
+private:
+  /// Insert the primitive types into the type plane. This is called
+  /// by the constructor to initialize the type plane.
+  void insertPrimitives();
+
+/// @}
+/// @name Data
+/// @{
+private:
+  /// A two dimensional table of Values indexed by type and slot number. This
+  /// allows for efficient lookup of a Value by its type and slot number.
+  ValueTable vTable;
+
+  /// A map of Values to unsigned integer. This allows for efficient lookup of
+  /// A Value's slot number in its type plane. 
+  ValueMap   vMap;
+
+  /// A one dimensional vector of Types indexed by slot number. Types are
+  /// handled separately because they are not Values. 
+  TypePlane  tPlane;
+
+  /// A map of Types to unsigned integer. This allows for efficient lookup of
+  /// a Type's slot number in the type plane.
+  TypeMap    tMap;
+
+/// @}
+
+};
+
+} // End llvm namespace
+
+// vim: sw=2 
+
+#endif