llvm-project/llvm/lib/Target/SystemZ/SystemZISelLowering.h

555 lines
21 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_LIB_TARGET_SYSTEMZ_SYSTEMZISELLOWERING_H
#define LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZISELLOWERING_H
#include "SystemZ.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/Target/TargetLowering.h"
namespace llvm {
namespace SystemZISD {
enum NodeType : unsigned {
FIRST_NUMBER = ISD::BUILTIN_OP_END,
// Return with a flag operand. Operand 0 is the chain operand.
RET_FLAG,
// Calls a function. Operand 0 is the chain operand and operand 1
// is the target address. The arguments start at operand 2.
// There is an optional glue operand at the end.
CALL,
SIBCALL,
// TLS calls. Like regular calls, except operand 1 is the TLS symbol.
// (The call target is implicitly __tls_get_offset.)
TLS_GDCALL,
TLS_LDCALL,
// Wraps a TargetGlobalAddress that should be loaded using PC-relative
// accesses (LARL). Operand 0 is the address.
PCREL_WRAPPER,
// Used in cases where an offset is applied to a TargetGlobalAddress.
// Operand 0 is the full TargetGlobalAddress and operand 1 is a
// PCREL_WRAPPER for an anchor point. This is used so that we can
// cheaply refer to either the full address or the anchor point
// as a register base.
PCREL_OFFSET,
// Integer absolute.
IABS,
// Integer comparisons. There are three operands: the two values
// to compare, and an integer of type SystemZICMP.
ICMP,
// Floating-point comparisons. The two operands are the values to compare.
FCMP,
// Test under mask. The first operand is ANDed with the second operand
// and the condition codes are set on the result. The third operand is
// a boolean that is true if the condition codes need to distinguish
// between CCMASK_TM_MIXED_MSB_0 and CCMASK_TM_MIXED_MSB_1 (which the
// register forms do but the memory forms don't).
TM,
// Branches if a condition is true. Operand 0 is the chain operand;
// operand 1 is the 4-bit condition-code mask, with bit N in
// big-endian order meaning "branch if CC=N"; operand 2 is the
// target block and operand 3 is the flag operand.
BR_CCMASK,
// Selects between operand 0 and operand 1. Operand 2 is the
// mask of condition-code values for which operand 0 should be
// chosen over operand 1; it has the same form as BR_CCMASK.
// Operand 3 is the flag operand.
SELECT_CCMASK,
// Evaluates to the gap between the stack pointer and the
// base of the dynamically-allocatable area.
ADJDYNALLOC,
// Extracts the value of a 32-bit access register. Operand 0 is
// the number of the register.
EXTRACT_ACCESS,
// Count number of bits set in operand 0 per byte.
POPCNT,
// Wrappers around the ISD opcodes of the same name. The output and
// first input operands are GR128s. The trailing numbers are the
// widths of the second operand in bits.
UMUL_LOHI64,
SDIVREM32,
SDIVREM64,
UDIVREM32,
UDIVREM64,
// Use a series of MVCs to copy bytes from one memory location to another.
// The operands are:
// - the target address
// - the source address
// - the constant length
//
// This isn't a memory opcode because we'd need to attach two
// MachineMemOperands rather than one.
MVC,
// Like MVC, but implemented as a loop that handles X*256 bytes
// followed by straight-line code to handle the rest (if any).
// The value of X is passed as an additional operand.
MVC_LOOP,
// Similar to MVC and MVC_LOOP, but for logic operations (AND, OR, XOR).
NC,
NC_LOOP,
OC,
OC_LOOP,
XC,
XC_LOOP,
// Use CLC to compare two blocks of memory, with the same comments
// as for MVC and MVC_LOOP.
CLC,
CLC_LOOP,
// Use an MVST-based sequence to implement stpcpy().
STPCPY,
// Use a CLST-based sequence to implement strcmp(). The two input operands
// are the addresses of the strings to compare.
STRCMP,
// Use an SRST-based sequence to search a block of memory. The first
// operand is the end address, the second is the start, and the third
// is the character to search for. CC is set to 1 on success and 2
// on failure.
SEARCH_STRING,
// Store the CC value in bits 29 and 28 of an integer.
IPM,
// Perform a serialization operation. (BCR 15,0 or BCR 14,0.)
SERIALIZE,
// Transaction begin. The first operand is the chain, the second
// the TDB pointer, and the third the immediate control field.
// Returns chain and glue.
TBEGIN,
TBEGIN_NOFLOAT,
// Transaction end. Just the chain operand. Returns chain and glue.
TEND,
// Create a vector constant by filling byte N of the result with bit
// 15-N of the single operand.
BYTE_MASK,
// Create a vector constant by replicating an element-sized RISBG-style mask.
// The first operand specifies the starting set bit and the second operand
// specifies the ending set bit. Both operands count from the MSB of the
// element.
ROTATE_MASK,
// Replicate a GPR scalar value into all elements of a vector.
REPLICATE,
// Create a vector from two i64 GPRs.
JOIN_DWORDS,
// Replicate one element of a vector into all elements. The first operand
// is the vector and the second is the index of the element to replicate.
SPLAT,
// Interleave elements from the high half of operand 0 and the high half
// of operand 1.
MERGE_HIGH,
// Likewise for the low halves.
MERGE_LOW,
// Concatenate the vectors in the first two operands, shift them left
// by the third operand, and take the first half of the result.
SHL_DOUBLE,
// Take one element of the first v2i64 operand and the one element of
// the second v2i64 operand and concatenate them to form a v2i64 result.
// The third operand is a 4-bit value of the form 0A0B, where A and B
// are the element selectors for the first operand and second operands
// respectively.
PERMUTE_DWORDS,
// Perform a general vector permute on vector operands 0 and 1.
// Each byte of operand 2 controls the corresponding byte of the result,
// in the same way as a byte-level VECTOR_SHUFFLE mask.
PERMUTE,
// Pack vector operands 0 and 1 into a single vector with half-sized elements.
PACK,
// Likewise, but saturate the result and set CC. PACKS_CC does signed
// saturation and PACKLS_CC does unsigned saturation.
PACKS_CC,
PACKLS_CC,
// Unpack the first half of vector operand 0 into double-sized elements.
// UNPACK_HIGH sign-extends and UNPACKL_HIGH zero-extends.
UNPACK_HIGH,
UNPACKL_HIGH,
// Likewise for the second half.
UNPACK_LOW,
UNPACKL_LOW,
// Shift each element of vector operand 0 by the number of bits specified
// by scalar operand 1.
VSHL_BY_SCALAR,
VSRL_BY_SCALAR,
VSRA_BY_SCALAR,
// For each element of the output type, sum across all sub-elements of
// operand 0 belonging to the corresponding element, and add in the
// rightmost sub-element of the corresponding element of operand 1.
VSUM,
// Compare integer vector operands 0 and 1 to produce the usual 0/-1
// vector result. VICMPE is for equality, VICMPH for "signed greater than"
// and VICMPHL for "unsigned greater than".
VICMPE,
VICMPH,
VICMPHL,
// Likewise, but also set the condition codes on the result.
VICMPES,
VICMPHS,
VICMPHLS,
// Compare floating-point vector operands 0 and 1 to preoduce the usual 0/-1
// vector result. VFCMPE is for "ordered and equal", VFCMPH for "ordered and
// greater than" and VFCMPHE for "ordered and greater than or equal to".
VFCMPE,
VFCMPH,
VFCMPHE,
// Likewise, but also set the condition codes on the result.
VFCMPES,
VFCMPHS,
VFCMPHES,
// Test floating-point data class for vectors.
VFTCI,
// Extend the even f32 elements of vector operand 0 to produce a vector
// of f64 elements.
VEXTEND,
// Round the f64 elements of vector operand 0 to f32s and store them in the
// even elements of the result.
VROUND,
// AND the two vector operands together and set CC based on the result.
VTM,
// String operations that set CC as a side-effect.
VFAE_CC,
VFAEZ_CC,
VFEE_CC,
VFEEZ_CC,
VFENE_CC,
VFENEZ_CC,
VISTR_CC,
VSTRC_CC,
VSTRCZ_CC,
// Wrappers around the inner loop of an 8- or 16-bit ATOMIC_SWAP or
// ATOMIC_LOAD_<op>.
//
// Operand 0: the address of the containing 32-bit-aligned field
// Operand 1: the second operand of <op>, in the high bits of an i32
// for everything except ATOMIC_SWAPW
// Operand 2: how many bits to rotate the i32 left to bring the first
// operand into the high bits
// Operand 3: the negative of operand 2, for rotating the other way
// Operand 4: the width of the field in bits (8 or 16)
ATOMIC_SWAPW = ISD::FIRST_TARGET_MEMORY_OPCODE,
ATOMIC_LOADW_ADD,
ATOMIC_LOADW_SUB,
ATOMIC_LOADW_AND,
ATOMIC_LOADW_OR,
ATOMIC_LOADW_XOR,
ATOMIC_LOADW_NAND,
ATOMIC_LOADW_MIN,
ATOMIC_LOADW_MAX,
ATOMIC_LOADW_UMIN,
ATOMIC_LOADW_UMAX,
// A wrapper around the inner loop of an ATOMIC_CMP_SWAP.
//
// Operand 0: the address of the containing 32-bit-aligned field
// Operand 1: the compare value, in the low bits of an i32
// Operand 2: the swap value, in the low bits of an i32
// Operand 3: how many bits to rotate the i32 left to bring the first
// operand into the high bits
// Operand 4: the negative of operand 2, for rotating the other way
// Operand 5: the width of the field in bits (8 or 16)
ATOMIC_CMP_SWAPW,
// Prefetch from the second operand using the 4-bit control code in
// the first operand. The code is 1 for a load prefetch and 2 for
// a store prefetch.
PREFETCH
};
// Return true if OPCODE is some kind of PC-relative address.
inline bool isPCREL(unsigned Opcode) {
return Opcode == PCREL_WRAPPER || Opcode == PCREL_OFFSET;
}
} // end namespace SystemZISD
namespace SystemZICMP {
// Describes whether an integer comparison needs to be signed or unsigned,
// or whether either type is OK.
enum {
Any,
UnsignedOnly,
SignedOnly
};
} // end namespace SystemZICMP
class SystemZSubtarget;
class SystemZTargetMachine;
class SystemZTargetLowering : public TargetLowering {
public:
explicit SystemZTargetLowering(const TargetMachine &TM,
const SystemZSubtarget &STI);
// Override TargetLowering.
MVT getScalarShiftAmountTy(const DataLayout &, EVT) const override {
return MVT::i32;
}
MVT getVectorIdxTy(const DataLayout &DL) const override {
// Only the lower 12 bits of an element index are used, so we don't
// want to clobber the upper 32 bits of a GPR unnecessarily.
return MVT::i32;
}
TargetLoweringBase::LegalizeTypeAction getPreferredVectorAction(EVT VT)
const override {
// Widen subvectors to the full width rather than promoting integer
// elements. This is better because:
//
// (a) it means that we can handle the ABI for passing and returning
// sub-128 vectors without having to handle them as legal types.
//
// (b) we don't have instructions to extend on load and truncate on store,
// so promoting the integers is less efficient.
//
// (c) there are no multiplication instructions for the widest integer
// type (v2i64).
if (VT.getVectorElementType().getSizeInBits() % 8 == 0)
return TypeWidenVector;
return TargetLoweringBase::getPreferredVectorAction(VT);
}
EVT getSetCCResultType(const DataLayout &DL, LLVMContext &,
EVT) const override;
bool isFMAFasterThanFMulAndFAdd(EVT VT) const override;
bool isFPImmLegal(const APFloat &Imm, EVT VT) const override;
bool isLegalICmpImmediate(int64_t Imm) const override;
bool isLegalAddImmediate(int64_t Imm) const override;
bool isLegalAddressingMode(const DataLayout &DL, const AddrMode &AM, Type *Ty,
unsigned AS) const override;
bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AS,
unsigned Align,
bool *Fast) const override;
bool isTruncateFree(Type *, Type *) const override;
bool isTruncateFree(EVT, EVT) const override;
const char *getTargetNodeName(unsigned Opcode) const override;
std::pair<unsigned, const TargetRegisterClass *>
getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
StringRef Constraint, MVT VT) const override;
TargetLowering::ConstraintType
getConstraintType(StringRef Constraint) const override;
TargetLowering::ConstraintWeight
getSingleConstraintMatchWeight(AsmOperandInfo &info,
const char *constraint) const override;
void LowerAsmOperandForConstraint(SDValue Op,
std::string &Constraint,
std::vector<SDValue> &Ops,
SelectionDAG &DAG) const override;
unsigned getInlineAsmMemConstraint(StringRef ConstraintCode) const override {
if (ConstraintCode.size() == 1) {
switch(ConstraintCode[0]) {
default:
break;
case 'Q':
return InlineAsm::Constraint_Q;
case 'R':
return InlineAsm::Constraint_R;
case 'S':
return InlineAsm::Constraint_S;
case 'T':
return InlineAsm::Constraint_T;
}
}
return TargetLowering::getInlineAsmMemConstraint(ConstraintCode);
}
/// If a physical register, this returns the register that receives the
/// exception address on entry to an EH pad.
unsigned
getExceptionPointerRegister(const Constant *PersonalityFn) const override {
return SystemZ::R6D;
}
/// If a physical register, this returns the register that receives the
/// exception typeid on entry to a landing pad.
unsigned
getExceptionSelectorRegister(const Constant *PersonalityFn) const override {
return SystemZ::R7D;
}
MachineBasicBlock *EmitInstrWithCustomInserter(MachineInstr *MI,
MachineBasicBlock *BB) const
override;
SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;
bool allowTruncateForTailCall(Type *, Type *) const override;
bool mayBeEmittedAsTailCall(CallInst *CI) const override;
SDValue LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv,
bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
SDLoc DL, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const override;
SDValue LowerCall(CallLoweringInfo &CLI,
SmallVectorImpl<SDValue> &InVals) const override;
bool CanLowerReturn(CallingConv::ID CallConv, MachineFunction &MF,
bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
LLVMContext &Context) const override;
SDValue LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool IsVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
SDLoc DL, SelectionDAG &DAG) const override;
SDValue prepareVolatileOrAtomicLoad(SDValue Chain, SDLoc DL,
SelectionDAG &DAG) const override;
SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const override;
private:
const SystemZSubtarget &Subtarget;
// Implement LowerOperation for individual opcodes.
SDValue lowerSETCC(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerBR_CC(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerGlobalAddress(GlobalAddressSDNode *Node,
SelectionDAG &DAG) const;
SDValue lowerTLSGetOffset(GlobalAddressSDNode *Node,
SelectionDAG &DAG, unsigned Opcode,
SDValue GOTOffset) const;
SDValue lowerGlobalTLSAddress(GlobalAddressSDNode *Node,
SelectionDAG &DAG) const;
SDValue lowerBlockAddress(BlockAddressSDNode *Node,
SelectionDAG &DAG) const;
SDValue lowerJumpTable(JumpTableSDNode *JT, SelectionDAG &DAG) const;
SDValue lowerConstantPool(ConstantPoolSDNode *CP, SelectionDAG &DAG) const;
SDValue lowerVASTART(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerVACOPY(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerSMUL_LOHI(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerUMUL_LOHI(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerSDIVREM(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerUDIVREM(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerBITCAST(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerOR(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerCTPOP(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerATOMIC_LOAD(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerATOMIC_STORE(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerATOMIC_LOAD_OP(SDValue Op, SelectionDAG &DAG,
unsigned Opcode) const;
SDValue lowerATOMIC_LOAD_SUB(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerATOMIC_CMP_SWAP(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerLOAD_SEQUENCE_POINT(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerSTACKSAVE(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerSTACKRESTORE(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerPREFETCH(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerINTRINSIC_W_CHAIN(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerSCALAR_TO_VECTOR(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerINSERT_VECTOR_ELT(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerEXTRACT_VECTOR_ELT(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerExtendVectorInreg(SDValue Op, SelectionDAG &DAG,
unsigned UnpackHigh) const;
SDValue lowerShift(SDValue Op, SelectionDAG &DAG, unsigned ByScalar) const;
SDValue combineExtract(SDLoc DL, EVT ElemVT, EVT VecVT, SDValue OrigOp,
unsigned Index, DAGCombinerInfo &DCI,
bool Force) const;
SDValue combineTruncateExtract(SDLoc DL, EVT TruncVT, SDValue Op,
DAGCombinerInfo &DCI) const;
// If the last instruction before MBBI in MBB was some form of COMPARE,
// try to replace it with a COMPARE AND BRANCH just before MBBI.
// CCMask and Target are the BRC-like operands for the branch.
// Return true if the change was made.
bool convertPrevCompareToBranch(MachineBasicBlock *MBB,
MachineBasicBlock::iterator MBBI,
unsigned CCMask,
MachineBasicBlock *Target) const;
// Implement EmitInstrWithCustomInserter for individual operation types.
MachineBasicBlock *emitSelect(MachineInstr *MI,
MachineBasicBlock *BB) const;
MachineBasicBlock *emitCondStore(MachineInstr *MI,
MachineBasicBlock *BB,
unsigned StoreOpcode, unsigned STOCOpcode,
bool Invert) const;
MachineBasicBlock *emitExt128(MachineInstr *MI,
MachineBasicBlock *MBB,
bool ClearEven, unsigned SubReg) const;
MachineBasicBlock *emitAtomicLoadBinary(MachineInstr *MI,
MachineBasicBlock *BB,
unsigned BinOpcode, unsigned BitSize,
bool Invert = false) const;
MachineBasicBlock *emitAtomicLoadMinMax(MachineInstr *MI,
MachineBasicBlock *MBB,
unsigned CompareOpcode,
unsigned KeepOldMask,
unsigned BitSize) const;
MachineBasicBlock *emitAtomicCmpSwapW(MachineInstr *MI,
MachineBasicBlock *BB) const;
MachineBasicBlock *emitMemMemWrapper(MachineInstr *MI,
MachineBasicBlock *BB,
unsigned Opcode) const;
MachineBasicBlock *emitStringWrapper(MachineInstr *MI,
MachineBasicBlock *BB,
unsigned Opcode) const;
MachineBasicBlock *emitTransactionBegin(MachineInstr *MI,
MachineBasicBlock *MBB,
unsigned Opcode,
bool NoFloat) const;
MachineBasicBlock *emitLoadAndTestCmp0(MachineInstr *MI,
MachineBasicBlock *MBB,
unsigned Opcode) const;
};
} // end namespace llvm
#endif