PPCISelLowering.h revision c703a8fbf8653ac8302ae368391a4954c307ca2c 
1//===-- PPCISelLowering.h - PPC32 DAG Lowering Interface --------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by Chris Lattner and is distributed under
6// the University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines the interfaces that PPC uses to lower LLVM code into a
11// selection DAG.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_TARGET_POWERPC_PPC32ISELLOWERING_H
16#define LLVM_TARGET_POWERPC_PPC32ISELLOWERING_H
17
18#include "llvm/Target/TargetLowering.h"
19#include "llvm/CodeGen/SelectionDAG.h"
20#include "PPC.h"
21
22namespace llvm {
23  namespace PPCISD {
24    enum NodeType {
25      // Start the numbering where the builting ops and target ops leave off.
26      FIRST_NUMBER = ISD::BUILTIN_OP_END+PPC::INSTRUCTION_LIST_END,
27
28      /// FSEL - Traditional three-operand fsel node.
29      ///
30      FSEL,
31
32      /// FCFID - The FCFID instruction, taking an f64 operand and producing
33      /// and f64 value containing the FP representation of the integer that
34      /// was temporarily in the f64 operand.
35      FCFID,
36
37      /// FCTI[D,W]Z - The FCTIDZ and FCTIWZ instructions, taking an f32 or f64
38      /// operand, producing an f64 value containing the integer representation
39      /// of that FP value.
40      FCTIDZ, FCTIWZ,
41
42      /// STFIWX - The STFIWX instruction.  The first operand is an input token
43      /// chain, then an f64 value to store, then an address to store it to,
44      /// then a SRCVALUE for the address.
45      STFIWX,
46
47      // VMADDFP, VNMSUBFP - The VMADDFP and VNMSUBFP instructions, taking
48      // three v4f32 operands and producing a v4f32 result.
49      VMADDFP, VNMSUBFP,
50
51      /// VPERM - The PPC VPERM Instruction.
52      ///
53      VPERM,
54
55      /// Hi/Lo - These represent the high and low 16-bit parts of a global
56      /// address respectively.  These nodes have two operands, the first of
57      /// which must be a TargetGlobalAddress, and the second of which must be a
58      /// Constant.  Selected naively, these turn into 'lis G+C' and 'li G+C',
59      /// though these are usually folded into other nodes.
60      Hi, Lo,
61
62      /// GlobalBaseReg - On Darwin, this node represents the result of the mflr
63      /// at function entry, used for PIC code.
64      GlobalBaseReg,
65
66      /// These nodes represent the 32-bit PPC shifts that operate on 6-bit
67      /// shift amounts.  These nodes are generated by the multi-precision shift
68      /// code.
69      SRL, SRA, SHL,
70
71      /// EXTSW_32 - This is the EXTSW instruction for use with "32-bit"
72      /// registers.
73      EXTSW_32,
74
75      /// STD_32 - This is the STD instruction for use with "32-bit" registers.
76      STD_32,
77
78      /// CALL - A direct function call.
79      CALL,
80
81      /// CHAIN,FLAG = MTCTR(VAL, CHAIN[, INFLAG]) - Directly corresponds to a
82      /// MTCTR instruction.
83      MTCTR,
84
85      /// CHAIN,FLAG = BCTRL(CHAIN, INFLAG) - Directly corresponds to a
86      /// BCTRL instruction.
87      BCTRL,
88
89      /// Return with a flag operand, matched by 'blr'
90      RET_FLAG,
91
92      /// R32 = MFCR(CRREG, INFLAG) - Represents the MFCR/MFOCRF instructions.
93      /// This copies the bits corresponding to the specified CRREG into the
94      /// resultant GPR.  Bits corresponding to other CR regs are undefined.
95      MFCR,
96
97      /// RESVEC = VCMP(LHS, RHS, OPC) - Represents one of the altivec VCMP*
98      /// instructions.  For lack of better number, we use the opcode number
99      /// encoding for the OPC field to identify the compare.  For example, 838
100      /// is VCMPGTSH.
101      VCMP,
102
103      /// RESVEC, OUTFLAG = VCMPo(LHS, RHS, OPC) - Represents one of the
104      /// altivec VCMP*o instructions.  For lack of better number, we use the
105      /// opcode number encoding for the OPC field to identify the compare.  For
106      /// example, 838 is VCMPGTSH.
107      VCMPo,
108
109      /// CHAIN = COND_BRANCH CHAIN, CRRC, OPC, DESTBB [, INFLAG] - This
110      /// corresponds to the COND_BRANCH pseudo instruction.  CRRC is the
111      /// condition register to branch on, OPC is the branch opcode to use (e.g.
112      /// PPC::BLE), DESTBB is the destination block to branch to, and INFLAG is
113      /// an optional input flag argument.
114      COND_BRANCH
115    };
116  }
117
118  /// Define some predicates that are used for node matching.
119  namespace PPC {
120    /// isVPKUHUMShuffleMask - Return true if this is the shuffle mask for a
121    /// VPKUHUM instruction.
122    bool isVPKUHUMShuffleMask(SDNode *N, bool isUnary);
123
124    /// isVPKUWUMShuffleMask - Return true if this is the shuffle mask for a
125    /// VPKUWUM instruction.
126    bool isVPKUWUMShuffleMask(SDNode *N, bool isUnary);
127
128    /// isVMRGLShuffleMask - Return true if this is a shuffle mask suitable for
129    /// a VRGL* instruction with the specified unit size (1,2 or 4 bytes).
130    bool isVMRGLShuffleMask(SDNode *N, unsigned UnitSize, bool isUnary);
131
132    /// isVMRGHShuffleMask - Return true if this is a shuffle mask suitable for
133    /// a VRGH* instruction with the specified unit size (1,2 or 4 bytes).
134    bool isVMRGHShuffleMask(SDNode *N, unsigned UnitSize, bool isUnary);
135
136    /// isVSLDOIShuffleMask - If this is a vsldoi shuffle mask, return the shift
137    /// amount, otherwise return -1.
138    int isVSLDOIShuffleMask(SDNode *N, bool isUnary);
139
140    /// isSplatShuffleMask - Return true if the specified VECTOR_SHUFFLE operand
141    /// specifies a splat of a single element that is suitable for input to
142    /// VSPLTB/VSPLTH/VSPLTW.
143    bool isSplatShuffleMask(SDNode *N, unsigned EltSize);
144
145    /// getVSPLTImmediate - Return the appropriate VSPLT* immediate to splat the
146    /// specified isSplatShuffleMask VECTOR_SHUFFLE mask.
147    unsigned getVSPLTImmediate(SDNode *N, unsigned EltSize);
148
149    /// get_VSPLTI_elt - If this is a build_vector of constants which can be
150    /// formed by using a vspltis[bhw] instruction of the specified element
151    /// size, return the constant being splatted.  The ByteSize field indicates
152    /// the number of bytes of each element [124] -> [bhw].
153    SDOperand get_VSPLTI_elt(SDNode *N, unsigned ByteSize, SelectionDAG &DAG);
154  }
155
156  class PPCTargetLowering : public TargetLowering {
157    int VarArgsFrameIndex;            // FrameIndex for start of varargs area.
158    int ReturnAddrIndex;              // FrameIndex for return slot.
159  public:
160    PPCTargetLowering(TargetMachine &TM);
161
162    /// getTargetNodeName() - This method returns the name of a target specific
163    /// DAG node.
164    virtual const char *getTargetNodeName(unsigned Opcode) const;
165
166    /// LowerOperation - Provide custom lowering hooks for some operations.
167    ///
168    virtual SDOperand LowerOperation(SDOperand Op, SelectionDAG &DAG);
169
170    virtual SDOperand PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const;
171
172    virtual void computeMaskedBitsForTargetNode(const SDOperand Op,
173                                                uint64_t Mask,
174                                                uint64_t &KnownZero,
175                                                uint64_t &KnownOne,
176                                                unsigned Depth = 0) const;
177
178    virtual MachineBasicBlock *InsertAtEndOfBasicBlock(MachineInstr *MI,
179                                                       MachineBasicBlock *MBB);
180
181    ConstraintType getConstraintType(char ConstraintLetter) const;
182    std::vector<unsigned>
183      getRegClassForInlineAsmConstraint(const std::string &Constraint,
184                                        MVT::ValueType VT) const;
185    bool isOperandValidForConstraint(SDOperand Op, char ConstraintLetter);
186
187    /// isLegalAddressImmediate - Return true if the integer value can be used
188    /// as the offset of the target addressing mode.
189    virtual bool isLegalAddressImmediate(int64_t V) const;
190  };
191}
192
193#endif   // LLVM_TARGET_POWERPC_PPC32ISELLOWERING_H
194