llvm-6502/lib/Target/SystemZ/SystemZISelLowering.h
Dan Gohman 98ca4f2a32 Major calling convention code refactoring.
Instead of awkwardly encoding calling-convention information with ISD::CALL,
ISD::FORMAL_ARGUMENTS, ISD::RET, and ISD::ARG_FLAGS nodes, TargetLowering
provides three virtual functions for targets to override:
LowerFormalArguments, LowerCall, and LowerRet, which replace the custom
lowering done on the special nodes. They provide the same information, but
in a more immediately usable format.

This also reworks much of the target-independent tail call logic. The
decision of whether or not to perform a tail call is now cleanly split
between target-independent portions, and the target dependent portion
in IsEligibleForTailCallOptimization.

This also synchronizes all in-tree targets, to help enable future
refactoring and feature work.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78142 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-05 01:29:28 +00:00

136 lines
5.0 KiB
C++

//==-- SystemZISelLowering.h - SystemZ DAG Lowering Interface ----*- C++ -*-==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that SystemZ uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_SystemZ_ISELLOWERING_H
#define LLVM_TARGET_SystemZ_ISELLOWERING_H
#include "SystemZ.h"
#include "SystemZRegisterInfo.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/Target/TargetLowering.h"
namespace llvm {
namespace SystemZISD {
enum {
FIRST_NUMBER = ISD::BUILTIN_OP_END,
/// Return with a flag operand. Operand 0 is the chain operand.
RET_FLAG,
/// CALL - These operations represent an abstract call
/// instruction, which includes a bunch of information.
CALL,
/// PCRelativeWrapper - PC relative address
PCRelativeWrapper,
/// CMP, UCMP - Compare instruction
CMP,
UCMP,
/// BRCOND - Conditional branch. Operand 0 is chain operand, operand 1 is
/// the block to branch if condition is true, operand 2 is condition code
/// and operand 3 is the flag operand produced by a CMP instruction.
BRCOND,
/// SELECT - Operands 0 and 1 are selection variables, operand 2 is
/// condition code and operand 3 is the flag operand.
SELECT
};
}
class SystemZSubtarget;
class SystemZTargetMachine;
class SystemZTargetLowering : public TargetLowering {
public:
explicit SystemZTargetLowering(SystemZTargetMachine &TM);
/// LowerOperation - Provide custom lowering hooks for some operations.
virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG);
/// getTargetNodeName - This method returns the name of a target specific
/// DAG node.
virtual const char *getTargetNodeName(unsigned Opcode) const;
/// getFunctionAlignment - Return the Log2 alignment of this function.
virtual unsigned getFunctionAlignment(const Function *F) const {
return 1;
}
SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG);
SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG);
SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG);
SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG);
SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG);
SDValue EmitCmp(SDValue LHS, SDValue RHS,
ISD::CondCode CC, SDValue &SystemZCC,
SelectionDAG &DAG);
MachineBasicBlock* EmitInstrWithCustomInserter(MachineInstr *MI,
MachineBasicBlock *BB) const;
private:
SDValue LowerCCCCallTo(SDValue Chain, SDValue Callee,
unsigned CallConv, bool isVarArg,
bool isTailCall,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals);
SDValue LowerCCCArguments(SDValue Chain,
unsigned CallConv,
bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl,
SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals);
SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
unsigned CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals);
virtual SDValue
LowerFormalArguments(SDValue Chain,
unsigned CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals);
virtual SDValue
LowerCall(SDValue Chain, SDValue Callee,
unsigned CallConv, bool isVarArg, bool isTailCall,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals);
virtual SDValue
LowerReturn(SDValue Chain,
unsigned CallConv, bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
DebugLoc dl, SelectionDAG &DAG);
const SystemZSubtarget &Subtarget;
const SystemZTargetMachine &TM;
const SystemZRegisterInfo *RegInfo;
};
} // namespace llvm
#endif // LLVM_TARGET_SystemZ_ISELLOWERING_H