Subzero: Use CFG-local arena allocation for relevant containers.

src/IceDefs.h

 //===- subzero/src/IceDefs.h - Common Subzero declaraions -------*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file declares various useful types and classes that have
@@ skipping 14 matching lines @@
 #include <map>
 #include <string>
 #include <vector>
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/BitVector.h"
 #include "llvm/ADT/ilist.h"
 #include "llvm/ADT/ilist_node.h"
 #include "llvm/ADT/SmallBitVector.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/Allocator.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/ELF.h"
 #include "llvm/Support/raw_ostream.h"
 
 namespace Ice {
 
 class Cfg;
 class CfgNode;
 class Constant;
 class FunctionDeclaration;
 class GlobalContext;
 class GlobalDeclaration;
 class Inst;
 class InstAssign;
 class InstPhi;
 class InstTarget;
 class LiveRange;
 class Liveness;
 class Operand;
 class TargetLowering;
 class Variable;
 class VariableDeclaration;
 class VariablesMetadata;
 
-// TODO: Switch over to LLVM's ADT container classes.
-// http://llvm.org/docs/ProgrammersManual.html#picking-the-right-data-structure-for-a-task
+typedef llvm::BumpPtrAllocatorImpl<llvm::MallocAllocator, 1024 * 1024>
+ArenaAllocator;
+
+ArenaAllocator *getCurrentCfgAllocator();
+
+template <typename T> struct CfgLocalAllocator {
+  using value_type = T;
+  CfgLocalAllocator() = default;
+  template <class U> CfgLocalAllocator(const CfgLocalAllocator<U> &) {}
+  T *allocate(std::size_t Num) {
+    return getCurrentCfgAllocator()->Allocate<T>(Num);
+  }
+  void deallocate(T *, std::size_t) {}
+};
+template <typename T, typename U>
+inline bool operator==(const CfgLocalAllocator<T> &,
+                       const CfgLocalAllocator<U> &) {
+  return true;
+}
+template <typename T, typename U>
+inline bool operator!=(const CfgLocalAllocator<T> &,
+                       const CfgLocalAllocator<U> &) {
+  return false;
+}
+
 typedef std::string IceString;
 typedef llvm::ilist<Inst> InstList;
 // Ideally PhiList would be llvm::ilist<InstPhi>, and similar for
 // AssignList, but this runs into issues with SFINAE.
 typedef InstList PhiList;
 typedef InstList AssignList;
-typedef std::vector<Variable *> VarList;
-typedef std::vector<CfgNode *> NodeList;
+// VarList and NodeList are arena-allocated from the Cfg's allocator.
+typedef std::vector<Variable *, CfgLocalAllocator<Variable *>> VarList;
+typedef std::vector<CfgNode *, CfgLocalAllocator<CfgNode *>> NodeList;
 typedef std::vector<Constant *> ConstantList;
 
 // SizeT is for holding small-ish limits like number of source
 // operands in an instruction.  It is used instead of size_t (which
 // may be 64-bits wide) when we want to save space.
 typedef uint32_t SizeT;
 
 // InstNumberT is for holding an instruction number.  Instruction
 // numbers are used for representing Variable live ranges.
 typedef int32_t InstNumberT;
@@ skipping 48 matching lines @@
   IceV_Most = IceV_All & ~IceV_LinearScan
 };
 typedef uint32_t VerboseMask;
 
 typedef llvm::raw_ostream Ostream;
 typedef llvm::raw_fd_ostream Fdstream;
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEDEFS_H