llvm-6502/lib/Target/Hexagon/HexagonISelLowering.h
Juergen Ributzka c7e77f91fe SelectionDAG: Teach the legalizer to split SETCC if VSELECT needs splitting too.
This patch reapplies r193676 with an additional fix for the Hexagon backend. The
SystemZ backend has already been fixed by r194148.

The Type Legalizer recognizes that VSELECT needs to be split, because the type
is to wide for the given target. The same does not always apply to SETCC,
because less space is required to encode the result of a comparison. As a result
VSELECT is split and SETCC is unrolled into scalar comparisons.

This commit fixes the issue by checking for VSELECT-SETCC patterns in the DAG
Combiner. If a matching pattern is found, then the result mask of SETCC is
promoted to the expected vector mask type for the given target. Now the type
legalizer will split both VSELECT and SETCC.

This allows the following X86 DAG Combine code to sucessfully detect the MIN/MAX
pattern. This fixes PR16695, PR17002, and <rdar://problem/14594431>.

Reviewed by Nadav

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194542 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-13 01:57:54 +00:00

180 lines
7.3 KiB
C++

//===-- HexagonISelLowering.h - Hexagon 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 Hexagon uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//
#ifndef Hexagon_ISELLOWERING_H
#define Hexagon_ISELLOWERING_H
#include "Hexagon.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/Target/TargetLowering.h"
namespace llvm {
namespace HexagonISD {
enum {
FIRST_NUMBER = ISD::BUILTIN_OP_END,
CONST32,
CONST32_GP, // For marking data present in GP.
CONST32_Int_Real,
FCONST32,
SETCC,
ADJDYNALLOC,
ARGEXTEND,
CMPICC, // Compare two GPR operands, set icc.
CMPFCC, // Compare two FP operands, set fcc.
BRICC, // Branch to dest on icc condition
BRFCC, // Branch to dest on fcc condition
SELECT_ICC, // Select between two values using the current ICC flags.
SELECT_FCC, // Select between two values using the current FCC flags.
Hi, Lo, // Hi/Lo operations, typically on a global address.
FTOI, // FP to Int within a FP register.
ITOF, // Int to FP within a FP register.
CALL, // A call instruction.
RET_FLAG, // Return with a flag operand.
BR_JT, // Jump table.
BARRIER, // Memory barrier.
WrapperJT,
WrapperCP,
WrapperCombineII,
WrapperCombineRR,
WrapperCombineRI_V4,
WrapperCombineIR_V4,
WrapperPackhl,
WrapperSplatB,
WrapperSplatH,
WrapperShuffEB,
WrapperShuffEH,
WrapperShuffOB,
WrapperShuffOH,
TC_RETURN,
EH_RETURN
};
}
class HexagonTargetLowering : public TargetLowering {
int VarArgsFrameOffset; // Frame offset to start of varargs area.
bool CanReturnSmallStruct(const Function* CalleeFn,
unsigned& RetSize) const;
public:
HexagonTargetMachine &TM;
explicit HexagonTargetLowering(HexagonTargetMachine &targetmachine);
/// IsEligibleForTailCallOptimization - Check whether the call is eligible
/// for tail call optimization. Targets which want to do tail call
/// optimization should implement this function.
bool
IsEligibleForTailCallOptimization(SDValue Callee,
CallingConv::ID CalleeCC,
bool isVarArg,
bool isCalleeStructRet,
bool isCallerStructRet,
const
SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
const SmallVectorImpl<ISD::InputArg> &Ins,
SelectionDAG& DAG) const;
virtual bool isTruncateFree(Type *Ty1, Type *Ty2) const;
virtual bool isTruncateFree(EVT VT1, EVT VT2) const;
virtual bool allowTruncateForTailCall(Type *Ty1, Type *Ty2) const;
virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const;
virtual const char *getTargetNodeName(unsigned Opcode) const;
SDValue LowerBR_JT(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerINLINEASM(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerEH_LABEL(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerEH_RETURN(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerFormalArguments(SDValue Chain,
CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
SDLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const;
SDValue LowerGLOBALADDRESS(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerCall(TargetLowering::CallLoweringInfo &CLI,
SmallVectorImpl<SDValue> &InVals) const;
SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
SDLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals,
const SmallVectorImpl<SDValue> &OutVals,
SDValue Callee) const;
SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerATOMIC_FENCE(SDValue Op, SelectionDAG& DAG) const;
SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerReturn(SDValue Chain,
CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
SDLoc dl, SelectionDAG &DAG) const;
virtual MachineBasicBlock
*EmitInstrWithCustomInserter(MachineInstr *MI,
MachineBasicBlock *BB) const;
SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG) const;
virtual EVT getSetCCResultType(LLVMContext &C, EVT VT) const {
if (!VT.isVector())
return MVT::i1;
else
return EVT::getVectorVT(C, MVT::i1, VT.getVectorNumElements());
}
virtual bool getPostIndexedAddressParts(SDNode *N, SDNode *Op,
SDValue &Base, SDValue &Offset,
ISD::MemIndexedMode &AM,
SelectionDAG &DAG) const;
std::pair<unsigned, const TargetRegisterClass*>
getRegForInlineAsmConstraint(const std::string &Constraint,
MVT VT) const;
// Intrinsics
virtual SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op,
SelectionDAG &DAG) const;
/// isLegalAddressingMode - Return true if the addressing mode represented
/// by AM is legal for this target, for a load/store of the specified type.
/// The type may be VoidTy, in which case only return true if the addressing
/// mode is legal for a load/store of any legal type.
/// TODO: Handle pre/postinc as well.
virtual bool isLegalAddressingMode(const AddrMode &AM, Type *Ty) const;
virtual bool isFPImmLegal(const APFloat &Imm, EVT VT) const;
/// isLegalICmpImmediate - Return true if the specified immediate is legal
/// icmp immediate, that is the target has icmp instructions which can
/// compare a register against the immediate without having to materialize
/// the immediate into a register.
virtual bool isLegalICmpImmediate(int64_t Imm) const;
};
} // end namespace llvm
#endif // Hexagon_ISELLOWERING_H