llvm-6502/include/llvm/CodeGen/MachineConstantPool.h
Chris Lattner 04a0f60b23 instead of keeping track of Constant/alignment pairs, actually compute the
offset of each entry from the start of the constant pool.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26077 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-09 04:44:32 +00:00

81 lines
2.7 KiB
C++

//===-- CodeGen/MachineConstantPool.h - Abstract Constant Pool --*- C++ -*-===//
//
// 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.
//
//===----------------------------------------------------------------------===//
//
// The MachineConstantPool class keeps track of constants referenced by a
// function which must be spilled to memory. This is used for constants which
// are unable to be used directly as operands to instructions, which typically
// include floating point and large integer constants.
//
// Instructions reference the address of these constant pool constants through
// the use of MO_ConstantPoolIndex values. When emitting assembly or machine
// code, these virtual address references are converted to refer to the
// address of the function constant pool values.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_MACHINECONSTANTPOOL_H
#define LLVM_CODEGEN_MACHINECONSTANTPOOL_H
#include <vector>
#include <iosfwd>
namespace llvm {
class Constant;
class TargetData;
/// MachineConstantPoolEntry - One entry in the constant pool.
///
struct MachineConstantPoolEntry {
/// Val - The constant itself.
Constant *Val;
/// Offset - The offset of the constant from the start of the constant pool.
unsigned Offset;
MachineConstantPoolEntry(Constant *V, unsigned O) : Val(V), Offset(O) {}
};
class MachineConstantPool {
const TargetData &TD;
unsigned PoolAlignment;
std::vector<MachineConstantPoolEntry> Constants;
public:
MachineConstantPool(const TargetData &td) : TD(td), PoolAlignment(1) {}
/// getConstantPoolAlignment - Return the log2 of the alignment required by
/// the whole constant pool, of which the first element must be aligned.
unsigned getConstantPoolAlignment() const { return PoolAlignment; }
/// getConstantPoolIndex - Create a new entry in the constant pool or return
/// an existing one. User must specify an alignment in bytes for the object.
///
unsigned getConstantPoolIndex(Constant *C, unsigned Alignment);
/// isEmpty - Return true if this constant pool contains no constants.
///
bool isEmpty() const { return Constants.empty(); }
const std::vector<MachineConstantPoolEntry> &getConstants() const {
return Constants;
}
/// print - Used by the MachineFunction printer to print information about
/// stack objects. Implemented in MachineFunction.cpp
///
void print(std::ostream &OS) const;
/// dump - Call print(std::cerr) to be called from the debugger.
///
void dump() const;
};
} // End llvm namespace
#endif