llvm/lib/Target/ARM/ARMConstantPoolValue.h
Evan Cheng c60e76d139 - Fix codegen for pc relative constant (e.g. JT) in thumb mode:
.set PCRELV0, (LJTI1_0_0-(LPCRELL0+4))
LPCRELL0:
        add r1, pc, #PCRELV0
This is not legal since add r1, pc, #c requires the constant be a multiple of 4.
Do the following instead:
        .set PCRELV0, (LJTI1_0_0-(LPCRELL0+4))
LPCRELL0:
        mov r1, #PCRELV0
        add r1, pc

- In thumb mode, it's not possible to use .set generate a pc relative stub
  address. The stub is ARM code which is in a different section from the thumb
  code. Load the value from a constpool instead.
- Some asm printing clean up.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33664 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-30 20:37:08 +00:00

66 lines
2.3 KiB
C++

//===- ARMConstantPoolValue.h - ARM constantpool value ----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Evan Cheng and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the ARM specific constantpool value class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_ARM_CONSTANTPOOLVALUE_H
#define LLVM_TARGET_ARM_CONSTANTPOOLVALUE_H
#include "llvm/CodeGen/MachineConstantPool.h"
namespace llvm {
namespace ARMCP {
enum ARMCPKind {
CPValue,
CPNonLazyPtr,
CPStub
};
}
/// ARMConstantPoolValue - ARM specific constantpool value. This is used to
/// represent PC relative displacement between the address of the load
/// instruction and the global value being loaded, i.e. (&GV-(LPIC+8)).
class ARMConstantPoolValue : public MachineConstantPoolValue {
GlobalValue *GV; // GlobalValue being loaded.
const char *S; // ExtSymbol being loaded.
unsigned LabelId; // Label id of the load.
ARMCP::ARMCPKind Kind; // non_lazy_ptr or stub?
unsigned char PCAdjust; // Extra adjustment if constantpool is pc relative.
// 8 for ARM, 4 for Thumb.
public:
ARMConstantPoolValue(GlobalValue *gv, unsigned id,
ARMCP::ARMCPKind Kind = ARMCP::CPValue,
unsigned char PCAdj = 0);
ARMConstantPoolValue(const char *s, unsigned id,
ARMCP::ARMCPKind Kind = ARMCP::CPValue,
unsigned char PCAdj = 0);
GlobalValue *getGV() const { return GV; }
const char *getSymbol() const { return S; }
unsigned getLabelId() const { return LabelId; }
bool isNonLazyPointer() const { return Kind == ARMCP::CPNonLazyPtr; }
bool isStub() const { return Kind == ARMCP::CPStub; }
unsigned char getPCAdjustment() const { return PCAdjust; }
virtual int getExistingMachineCPValue(MachineConstantPool *CP,
unsigned Alignment);
virtual void AddSelectionDAGCSEId(FoldingSetNodeID &ID);
virtual void print(std::ostream &O) const;
};
}
#endif