llvm-6502/lib/Target/X86/X86ISelLowering.h
Chris Lattner 6458f1807d update comments
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30663 91177308-0d34-0410-b5e6-96231b3b80d8
2006-09-28 23:33:12 +00:00

424 lines
18 KiB
C++

//===-- X86ISelLowering.h - X86 DAG Lowering Interface ----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that X86 uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//
#ifndef X86ISELLOWERING_H
#define X86ISELLOWERING_H
#include "X86Subtarget.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/CodeGen/SelectionDAG.h"
namespace llvm {
namespace X86ISD {
// X86 Specific DAG Nodes
enum NodeType {
// Start the numbering where the builtin ops leave off.
FIRST_NUMBER = ISD::BUILTIN_OP_END+X86::INSTRUCTION_LIST_END,
/// SHLD, SHRD - Double shift instructions. These correspond to
/// X86::SHLDxx and X86::SHRDxx instructions.
SHLD,
SHRD,
/// FAND - Bitwise logical AND of floating point values. This corresponds
/// to X86::ANDPS or X86::ANDPD.
FAND,
/// FXOR - Bitwise logical XOR of floating point values. This corresponds
/// to X86::XORPS or X86::XORPD.
FXOR,
/// FILD, FILD_FLAG - This instruction implements SINT_TO_FP with the
/// integer source in memory and FP reg result. This corresponds to the
/// X86::FILD*m instructions. It has three inputs (token chain, address,
/// and source type) and two outputs (FP value and token chain). FILD_FLAG
/// also produces a flag).
FILD,
FILD_FLAG,
/// FP_TO_INT*_IN_MEM - This instruction implements FP_TO_SINT with the
/// integer destination in memory and a FP reg source. This corresponds
/// to the X86::FIST*m instructions and the rounding mode change stuff. It
/// has two inputs (token chain and address) and two outputs (int value and
/// token chain).
FP_TO_INT16_IN_MEM,
FP_TO_INT32_IN_MEM,
FP_TO_INT64_IN_MEM,
/// FLD - This instruction implements an extending load to FP stack slots.
/// This corresponds to the X86::FLD32m / X86::FLD64m. It takes a chain
/// operand, ptr to load from, and a ValueType node indicating the type
/// to load to.
FLD,
/// FST - This instruction implements a truncating store to FP stack
/// slots. This corresponds to the X86::FST32m / X86::FST64m. It takes a
/// chain operand, value to store, address, and a ValueType to store it
/// as.
FST,
/// FP_SET_RESULT - This corresponds to FpGETRESULT pseudo instrcuction
/// which copies from ST(0) to the destination. It takes a chain and writes
/// a RFP result and a chain.
FP_GET_RESULT,
/// FP_SET_RESULT - This corresponds to FpSETRESULT pseudo instrcuction
/// which copies the source operand to ST(0). It takes a chain and writes
/// a chain and a flag.
FP_SET_RESULT,
/// CALL/TAILCALL - These operations represent an abstract X86 call
/// instruction, which includes a bunch of information. In particular the
/// operands of these node are:
///
/// #0 - The incoming token chain
/// #1 - The callee
/// #2 - The number of arg bytes the caller pushes on the stack.
/// #3 - The number of arg bytes the callee pops off the stack.
/// #4 - The value to pass in AL/AX/EAX (optional)
/// #5 - The value to pass in DL/DX/EDX (optional)
///
/// The result values of these nodes are:
///
/// #0 - The outgoing token chain
/// #1 - The first register result value (optional)
/// #2 - The second register result value (optional)
///
/// The CALL vs TAILCALL distinction boils down to whether the callee is
/// known not to modify the caller's stack frame, as is standard with
/// LLVM.
CALL,
TAILCALL,
/// RDTSC_DAG - This operation implements the lowering for
/// readcyclecounter
RDTSC_DAG,
/// X86 compare and logical compare instructions.
CMP, TEST, COMI, UCOMI,
/// X86 SetCC. Operand 1 is condition code, and operand 2 is the flag
/// operand produced by a CMP instruction.
SETCC,
/// X86 conditional moves. Operand 1 and operand 2 are the two values
/// to select from (operand 1 is a R/W operand). Operand 3 is the condition
/// code, and operand 4 is the flag operand produced by a CMP or TEST
/// instruction. It also writes a flag result.
CMOV,
/// X86 conditional branches. Operand 1 is the chain operand, operand 2
/// is the block to branch if condition is true, operand 3 is the
/// condition code, and operand 4 is the flag operand produced by a CMP
/// or TEST instruction.
BRCOND,
/// Return with a flag operand. Operand 1 is the chain operand, operand
/// 2 is the number of bytes of stack to pop.
RET_FLAG,
/// REP_STOS - Repeat fill, corresponds to X86::REP_STOSx.
REP_STOS,
/// REP_MOVS - Repeat move, corresponds to X86::REP_MOVSx.
REP_MOVS,
/// LOAD_PACK Load a 128-bit packed float / double value. It has the same
/// operands as a normal load.
LOAD_PACK,
/// LOAD_UA Load an unaligned 128-bit value. It has the same operands as
/// a normal load.
LOAD_UA,
/// GlobalBaseReg - On Darwin, this node represents the result of the popl
/// at function entry, used for PIC code.
GlobalBaseReg,
/// Wrapper - A wrapper node for TargetConstantPool,
/// TargetExternalSymbol, and TargetGlobalAddress.
Wrapper,
/// S2VEC - X86 version of SCALAR_TO_VECTOR. The destination base does not
/// have to match the operand type.
S2VEC,
/// PEXTRW - Extract a 16-bit value from a vector and zero extend it to
/// i32, corresponds to X86::PEXTRW.
PEXTRW,
/// PINSRW - Insert the lower 16-bits of a 32-bit value to a vector,
/// corresponds to X86::PINSRW.
PINSRW
};
// X86 specific condition code. These correspond to X86_*_COND in
// X86InstrInfo.td. They must be kept in synch.
enum CondCode {
COND_A = 0,
COND_AE = 1,
COND_B = 2,
COND_BE = 3,
COND_E = 4,
COND_G = 5,
COND_GE = 6,
COND_L = 7,
COND_LE = 8,
COND_NE = 9,
COND_NO = 10,
COND_NP = 11,
COND_NS = 12,
COND_O = 13,
COND_P = 14,
COND_S = 15,
COND_INVALID
};
}
/// Define some predicates that are used for node matching.
namespace X86 {
/// isPSHUFDMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to PSHUFD.
bool isPSHUFDMask(SDNode *N);
/// isPSHUFHWMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to PSHUFD.
bool isPSHUFHWMask(SDNode *N);
/// isPSHUFLWMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to PSHUFD.
bool isPSHUFLWMask(SDNode *N);
/// isSHUFPMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to SHUFP*.
bool isSHUFPMask(SDNode *N);
/// isMOVHLPSMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to MOVHLPS.
bool isMOVHLPSMask(SDNode *N);
/// isMOVLPMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to MOVLP{S|D}.
bool isMOVLPMask(SDNode *N);
/// isMOVHPMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to MOVHP{S|D}
/// as well as MOVLHPS.
bool isMOVHPMask(SDNode *N);
/// isUNPCKLMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to UNPCKL.
bool isUNPCKLMask(SDNode *N, bool V2IsSplat = false);
/// isUNPCKHMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to UNPCKH.
bool isUNPCKHMask(SDNode *N, bool V2IsSplat = false);
/// isUNPCKL_v_undef_Mask - Special case of isUNPCKLMask for canonical form
/// of vector_shuffle v, v, <0, 4, 1, 5>, i.e. vector_shuffle v, undef,
/// <0, 0, 1, 1>
bool isUNPCKL_v_undef_Mask(SDNode *N);
/// isMOVLMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to MOVSS,
/// MOVSD, and MOVD, i.e. setting the lowest element.
bool isMOVLMask(SDNode *N);
/// isMOVSHDUPMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to MOVSHDUP.
bool isMOVSHDUPMask(SDNode *N);
/// isMOVSLDUPMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a shuffle of elements that is suitable for input to MOVSLDUP.
bool isMOVSLDUPMask(SDNode *N);
/// isSplatMask - Return true if the specified VECTOR_SHUFFLE operand
/// specifies a splat of a single element.
bool isSplatMask(SDNode *N);
/// getShuffleSHUFImmediate - Return the appropriate immediate to shuffle
/// the specified isShuffleMask VECTOR_SHUFFLE mask with PSHUF* and SHUFP*
/// instructions.
unsigned getShuffleSHUFImmediate(SDNode *N);
/// getShufflePSHUFHWImmediate - Return the appropriate immediate to shuffle
/// the specified isShuffleMask VECTOR_SHUFFLE mask with PSHUFHW
/// instructions.
unsigned getShufflePSHUFHWImmediate(SDNode *N);
/// getShufflePSHUFKWImmediate - Return the appropriate immediate to shuffle
/// the specified isShuffleMask VECTOR_SHUFFLE mask with PSHUFLW
/// instructions.
unsigned getShufflePSHUFLWImmediate(SDNode *N);
}
//===----------------------------------------------------------------------===//
// X86TargetLowering - X86 Implementation of the TargetLowering interface
class X86TargetLowering : public TargetLowering {
int VarArgsFrameIndex; // FrameIndex for start of varargs area.
int RegSaveFrameIndex; // X86-64 vararg func register save area.
unsigned VarArgsGPOffset; // X86-64 vararg func int reg offset.
unsigned VarArgsFPOffset; // X86-64 vararg func fp reg offset.
int ReturnAddrIndex; // FrameIndex for return slot.
int BytesToPopOnReturn; // Number of arg bytes ret should pop.
int BytesCallerReserves; // Number of arg bytes caller makes.
public:
X86TargetLowering(TargetMachine &TM);
// Return the number of bytes that a function should pop when it returns (in
// addition to the space used by the return address).
//
unsigned getBytesToPopOnReturn() const { return BytesToPopOnReturn; }
// Return the number of bytes that the caller reserves for arguments passed
// to this function.
unsigned getBytesCallerReserves() const { return BytesCallerReserves; }
/// LowerOperation - Provide custom lowering hooks for some operations.
///
virtual SDOperand LowerOperation(SDOperand Op, SelectionDAG &DAG);
virtual std::pair<SDOperand, SDOperand>
LowerFrameReturnAddress(bool isFrameAddr, SDOperand Chain, unsigned Depth,
SelectionDAG &DAG);
virtual SDOperand PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const;
virtual MachineBasicBlock *InsertAtEndOfBasicBlock(MachineInstr *MI,
MachineBasicBlock *MBB);
/// getTargetNodeName - This method returns the name of a target specific
/// DAG node.
virtual const char *getTargetNodeName(unsigned Opcode) const;
/// computeMaskedBitsForTargetNode - Determine which of the bits specified
/// in Mask are known to be either zero or one and return them in the
/// KnownZero/KnownOne bitsets.
virtual void computeMaskedBitsForTargetNode(const SDOperand Op,
uint64_t Mask,
uint64_t &KnownZero,
uint64_t &KnownOne,
unsigned Depth = 0) const;
SDOperand getReturnAddressFrameIndex(SelectionDAG &DAG);
ConstraintType getConstraintType(char ConstraintLetter) const;
std::vector<unsigned>
getRegClassForInlineAsmConstraint(const std::string &Constraint,
MVT::ValueType VT) const;
/// getRegForInlineAsmConstraint - Given a physical register constraint (e.g.
/// {edx}), return the register number and the register class for the
/// register. This should only be used for C_Register constraints. On error,
/// this returns a register number of 0.
std::pair<unsigned, const TargetRegisterClass*>
getRegForInlineAsmConstraint(const std::string &Constraint,
MVT::ValueType VT) const;
/// isLegalAddressImmediate - Return true if the integer value or
/// GlobalValue can be used as the offset of the target addressing mode.
virtual bool isLegalAddressImmediate(int64_t V) const;
virtual bool isLegalAddressImmediate(GlobalValue *GV) const;
/// isShuffleMaskLegal - Targets can use this to indicate that they only
/// support *some* VECTOR_SHUFFLE operations, those with specific masks.
/// By default, if a target supports the VECTOR_SHUFFLE node, all mask values
/// are assumed to be legal.
virtual bool isShuffleMaskLegal(SDOperand Mask, MVT::ValueType VT) const;
/// isVectorClearMaskLegal - Similar to isShuffleMaskLegal. This is
/// used by Targets can use this to indicate if there is a suitable
/// VECTOR_SHUFFLE that can be used to replace a VAND with a constant
/// pool entry.
virtual bool isVectorClearMaskLegal(std::vector<SDOperand> &BVOps,
MVT::ValueType EVT,
SelectionDAG &DAG) const;
private:
/// Subtarget - Keep a pointer to the X86Subtarget around so that we can
/// make the right decision when generating code for different targets.
const X86Subtarget *Subtarget;
/// X86StackPtr - X86 physical register used as stack ptr.
unsigned X86StackPtr;
/// X86ScalarSSE - Select between SSE2 or x87 floating point ops.
bool X86ScalarSSE;
// C Calling Convention implementation.
SDOperand LowerCCCArguments(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerCCCCallTo(SDOperand Op, SelectionDAG &DAG);
// X86-64 C Calling Convention implementation.
SDOperand LowerX86_64CCCArguments(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerX86_64CCCCallTo(SDOperand Op, SelectionDAG &DAG);
// Fast Calling Convention implementation.
SDOperand LowerFastCCArguments(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerFastCCCallTo(SDOperand Op, SelectionDAG &DAG,
bool isFastCall);
// StdCall Calling Convention implementation.
SDOperand LowerStdCallCCArguments(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerStdCallCCCallTo(SDOperand Op, SelectionDAG &DAG);
// FastCall Calling Convention implementation.
SDOperand LowerFastCallCCArguments(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerBUILD_VECTOR(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerVECTOR_SHUFFLE(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerEXTRACT_VECTOR_ELT(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerINSERT_VECTOR_ELT(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerSCALAR_TO_VECTOR(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerConstantPool(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerGlobalAddress(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerExternalSymbol(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerShift(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerSINT_TO_FP(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerFP_TO_SINT(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerFABS(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerFNEG(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerSETCC(SDOperand Op, SelectionDAG &DAG, SDOperand Chain);
SDOperand LowerSELECT(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerBRCOND(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerMEMSET(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerMEMCPY(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerJumpTable(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerCALL(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerRET(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerFORMAL_ARGUMENTS(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerREADCYCLCECOUNTER(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerVASTART(SDOperand Op, SelectionDAG &DAG);
SDOperand LowerINTRINSIC_WO_CHAIN(SDOperand Op, SelectionDAG &DAG);
};
}
// FASTCC_NUM_INT_ARGS_INREGS - This is the max number of integer arguments
// to pass in registers. 0 is none, 1 is is "use EAX", 2 is "use EAX and
// EDX". Anything more is illegal.
//
// FIXME: The linscan register allocator currently has problem with
// coalescing. At the time of this writing, whenever it decides to coalesce
// a physreg with a virtreg, this increases the size of the physreg's live
// range, and the live range cannot ever be reduced. This causes problems if
// too many physregs are coaleced with virtregs, which can cause the register
// allocator to wedge itself.
//
// This code triggers this problem more often if we pass args in registers,
// so disable it until this is fixed.
//
#define FASTCC_NUM_INT_ARGS_INREGS 0
#endif // X86ISELLOWERING_H