SelectionDAGNodes.h revision f2ddf15dc7232487cbea9061eab92145165421ba
1//===-- llvm/CodeGen/SelectionDAGNodes.h - SelectionDAG Nodes ---*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file declares the SDNode class and derived classes, which are used to
11// represent the nodes and operations present in a SelectionDAG.  These nodes
12// and operations are machine code level operations, with some similarities to
13// the GCC RTL representation.
14//
15// Clients should include the SelectionDAG.h file instead of this file directly.
16//
17//===----------------------------------------------------------------------===//
18
19#ifndef LLVM_CODEGEN_SELECTIONDAGNODES_H
20#define LLVM_CODEGEN_SELECTIONDAGNODES_H
21
22#include "llvm/Constants.h"
23#include "llvm/ADT/FoldingSet.h"
24#include "llvm/ADT/GraphTraits.h"
25#include "llvm/ADT/ilist_node.h"
26#include "llvm/ADT/SmallVector.h"
27#include "llvm/ADT/STLExtras.h"
28#include "llvm/CodeGen/ValueTypes.h"
29#include "llvm/CodeGen/MachineMemOperand.h"
30#include "llvm/Support/MathExtras.h"
31#include "llvm/System/DataTypes.h"
32#include "llvm/Support/DebugLoc.h"
33#include <cassert>
34
35namespace llvm {
36
37class SelectionDAG;
38class GlobalValue;
39class MachineBasicBlock;
40class MachineConstantPoolValue;
41class SDNode;
42class Value;
43class MCSymbol;
44template <typename T> struct DenseMapInfo;
45template <typename T> struct simplify_type;
46template <typename T> struct ilist_traits;
47
48void checkForCycles(const SDNode *N);
49
50/// SDVTList - This represents a list of ValueType's that has been intern'd by
51/// a SelectionDAG.  Instances of this simple value class are returned by
52/// SelectionDAG::getVTList(...).
53///
54struct SDVTList {
55  const EVT *VTs;
56  unsigned int NumVTs;
57};
58
59/// ISD namespace - This namespace contains an enum which represents all of the
60/// SelectionDAG node types and value types.
61///
62namespace ISD {
63
64  //===--------------------------------------------------------------------===//
65  /// ISD::NodeType enum - This enum defines the target-independent operators
66  /// for a SelectionDAG.
67  ///
68  /// Targets may also define target-dependent operator codes for SDNodes. For
69  /// example, on x86, these are the enum values in the X86ISD namespace.
70  /// Targets should aim to use target-independent operators to model their
71  /// instruction sets as much as possible, and only use target-dependent
72  /// operators when they have special requirements.
73  ///
74  /// Finally, during and after selection proper, SNodes may use special
75  /// operator codes that correspond directly with MachineInstr opcodes. These
76  /// are used to represent selected instructions. See the isMachineOpcode()
77  /// and getMachineOpcode() member functions of SDNode.
78  ///
79  enum NodeType {
80    // DELETED_NODE - This is an illegal value that is used to catch
81    // errors.  This opcode is not a legal opcode for any node.
82    DELETED_NODE,
83
84    // EntryToken - This is the marker used to indicate the start of the region.
85    EntryToken,
86
87    // TokenFactor - This node takes multiple tokens as input and produces a
88    // single token result.  This is used to represent the fact that the operand
89    // operators are independent of each other.
90    TokenFactor,
91
92    // AssertSext, AssertZext - These nodes record if a register contains a
93    // value that has already been zero or sign extended from a narrower type.
94    // These nodes take two operands.  The first is the node that has already
95    // been extended, and the second is a value type node indicating the width
96    // of the extension
97    AssertSext, AssertZext,
98
99    // Various leaf nodes.
100    BasicBlock, VALUETYPE, CONDCODE, Register,
101    Constant, ConstantFP,
102    GlobalAddress, GlobalTLSAddress, FrameIndex,
103    JumpTable, ConstantPool, ExternalSymbol, BlockAddress,
104
105    // The address of the GOT
106    GLOBAL_OFFSET_TABLE,
107
108    // FRAMEADDR, RETURNADDR - These nodes represent llvm.frameaddress and
109    // llvm.returnaddress on the DAG.  These nodes take one operand, the index
110    // of the frame or return address to return.  An index of zero corresponds
111    // to the current function's frame or return address, an index of one to the
112    // parent's frame or return address, and so on.
113    FRAMEADDR, RETURNADDR,
114
115    // FRAME_TO_ARGS_OFFSET - This node represents offset from frame pointer to
116    // first (possible) on-stack argument. This is needed for correct stack
117    // adjustment during unwind.
118    FRAME_TO_ARGS_OFFSET,
119
120    // RESULT, OUTCHAIN = EXCEPTIONADDR(INCHAIN) - This node represents the
121    // address of the exception block on entry to an landing pad block.
122    EXCEPTIONADDR,
123
124    // RESULT, OUTCHAIN = LSDAADDR(INCHAIN) - This node represents the
125    // address of the Language Specific Data Area for the enclosing function.
126    LSDAADDR,
127
128    // RESULT, OUTCHAIN = EHSELECTION(INCHAIN, EXCEPTION) - This node represents
129    // the selection index of the exception thrown.
130    EHSELECTION,
131
132    // OUTCHAIN = EH_RETURN(INCHAIN, OFFSET, HANDLER) - This node represents
133    // 'eh_return' gcc dwarf builtin, which is used to return from
134    // exception. The general meaning is: adjust stack by OFFSET and pass
135    // execution to HANDLER. Many platform-related details also :)
136    EH_RETURN,
137
138    // TargetConstant* - Like Constant*, but the DAG does not do any folding or
139    // simplification of the constant.
140    TargetConstant,
141    TargetConstantFP,
142
143    // TargetGlobalAddress - Like GlobalAddress, but the DAG does no folding or
144    // anything else with this node, and this is valid in the target-specific
145    // dag, turning into a GlobalAddress operand.
146    TargetGlobalAddress,
147    TargetGlobalTLSAddress,
148    TargetFrameIndex,
149    TargetJumpTable,
150    TargetConstantPool,
151    TargetExternalSymbol,
152    TargetBlockAddress,
153
154    /// RESULT = INTRINSIC_WO_CHAIN(INTRINSICID, arg1, arg2, ...)
155    /// This node represents a target intrinsic function with no side effects.
156    /// The first operand is the ID number of the intrinsic from the
157    /// llvm::Intrinsic namespace.  The operands to the intrinsic follow.  The
158    /// node has returns the result of the intrinsic.
159    INTRINSIC_WO_CHAIN,
160
161    /// RESULT,OUTCHAIN = INTRINSIC_W_CHAIN(INCHAIN, INTRINSICID, arg1, ...)
162    /// This node represents a target intrinsic function with side effects that
163    /// returns a result.  The first operand is a chain pointer.  The second is
164    /// the ID number of the intrinsic from the llvm::Intrinsic namespace.  The
165    /// operands to the intrinsic follow.  The node has two results, the result
166    /// of the intrinsic and an output chain.
167    INTRINSIC_W_CHAIN,
168
169    /// OUTCHAIN = INTRINSIC_VOID(INCHAIN, INTRINSICID, arg1, arg2, ...)
170    /// This node represents a target intrinsic function with side effects that
171    /// does not return a result.  The first operand is a chain pointer.  The
172    /// second is the ID number of the intrinsic from the llvm::Intrinsic
173    /// namespace.  The operands to the intrinsic follow.
174    INTRINSIC_VOID,
175
176    // CopyToReg - This node has three operands: a chain, a register number to
177    // set to this value, and a value.
178    CopyToReg,
179
180    // CopyFromReg - This node indicates that the input value is a virtual or
181    // physical register that is defined outside of the scope of this
182    // SelectionDAG.  The register is available from the RegisterSDNode object.
183    CopyFromReg,
184
185    // UNDEF - An undefined node
186    UNDEF,
187
188    // EXTRACT_ELEMENT - This is used to get the lower or upper (determined by
189    // a Constant, which is required to be operand #1) half of the integer or
190    // float value specified as operand #0.  This is only for use before
191    // legalization, for values that will be broken into multiple registers.
192    EXTRACT_ELEMENT,
193
194    // BUILD_PAIR - This is the opposite of EXTRACT_ELEMENT in some ways.  Given
195    // two values of the same integer value type, this produces a value twice as
196    // big.  Like EXTRACT_ELEMENT, this can only be used before legalization.
197    BUILD_PAIR,
198
199    // MERGE_VALUES - This node takes multiple discrete operands and returns
200    // them all as its individual results.  This nodes has exactly the same
201    // number of inputs and outputs. This node is useful for some pieces of the
202    // code generator that want to think about a single node with multiple
203    // results, not multiple nodes.
204    MERGE_VALUES,
205
206    // Simple integer binary arithmetic operators.
207    ADD, SUB, MUL, SDIV, UDIV, SREM, UREM,
208
209    // SMUL_LOHI/UMUL_LOHI - Multiply two integers of type iN, producing
210    // a signed/unsigned value of type i[2*N], and return the full value as
211    // two results, each of type iN.
212    SMUL_LOHI, UMUL_LOHI,
213
214    // SDIVREM/UDIVREM - Divide two integers and produce both a quotient and
215    // remainder result.
216    SDIVREM, UDIVREM,
217
218    // CARRY_FALSE - This node is used when folding other nodes,
219    // like ADDC/SUBC, which indicate the carry result is always false.
220    CARRY_FALSE,
221
222    // Carry-setting nodes for multiple precision addition and subtraction.
223    // These nodes take two operands of the same value type, and produce two
224    // results.  The first result is the normal add or sub result, the second
225    // result is the carry flag result.
226    ADDC, SUBC,
227
228    // Carry-using nodes for multiple precision addition and subtraction.  These
229    // nodes take three operands: The first two are the normal lhs and rhs to
230    // the add or sub, and the third is the input carry flag.  These nodes
231    // produce two results; the normal result of the add or sub, and the output
232    // carry flag.  These nodes both read and write a carry flag to allow them
233    // to them to be chained together for add and sub of arbitrarily large
234    // values.
235    ADDE, SUBE,
236
237    // RESULT, BOOL = [SU]ADDO(LHS, RHS) - Overflow-aware nodes for addition.
238    // These nodes take two operands: the normal LHS and RHS to the add. They
239    // produce two results: the normal result of the add, and a boolean that
240    // indicates if an overflow occured (*not* a flag, because it may be stored
241    // to memory, etc.).  If the type of the boolean is not i1 then the high
242    // bits conform to getBooleanContents.
243    // These nodes are generated from the llvm.[su]add.with.overflow intrinsics.
244    SADDO, UADDO,
245
246    // Same for subtraction
247    SSUBO, USUBO,
248
249    // Same for multiplication
250    SMULO, UMULO,
251
252    // Simple binary floating point operators.
253    FADD, FSUB, FMUL, FDIV, FREM,
254
255    // FCOPYSIGN(X, Y) - Return the value of X with the sign of Y.  NOTE: This
256    // DAG node does not require that X and Y have the same type, just that they
257    // are both floating point.  X and the result must have the same type.
258    // FCOPYSIGN(f32, f64) is allowed.
259    FCOPYSIGN,
260
261    // INT = FGETSIGN(FP) - Return the sign bit of the specified floating point
262    // value as an integer 0/1 value.
263    FGETSIGN,
264
265    /// BUILD_VECTOR(ELT0, ELT1, ELT2, ELT3,...) - Return a vector with the
266    /// specified, possibly variable, elements.  The number of elements is
267    /// required to be a power of two.  The types of the operands must all be
268    /// the same and must match the vector element type, except that integer
269    /// types are allowed to be larger than the element type, in which case
270    /// the operands are implicitly truncated.
271    BUILD_VECTOR,
272
273    /// INSERT_VECTOR_ELT(VECTOR, VAL, IDX) - Returns VECTOR with the element
274    /// at IDX replaced with VAL.  If the type of VAL is larger than the vector
275    /// element type then VAL is truncated before replacement.
276    INSERT_VECTOR_ELT,
277
278    /// EXTRACT_VECTOR_ELT(VECTOR, IDX) - Returns a single element from VECTOR
279    /// identified by the (potentially variable) element number IDX.  If the
280    /// return type is an integer type larger than the element type of the
281    /// vector, the result is extended to the width of the return type.
282    EXTRACT_VECTOR_ELT,
283
284    /// CONCAT_VECTORS(VECTOR0, VECTOR1, ...) - Given a number of values of
285    /// vector type with the same length and element type, this produces a
286    /// concatenated vector result value, with length equal to the sum of the
287    /// lengths of the input vectors.
288    CONCAT_VECTORS,
289
290    /// EXTRACT_SUBVECTOR(VECTOR, IDX) - Returns a subvector from VECTOR (an
291    /// vector value) starting with the (potentially variable) element number
292    /// IDX, which must be a multiple of the result vector length.
293    EXTRACT_SUBVECTOR,
294
295    /// VECTOR_SHUFFLE(VEC1, VEC2) - Returns a vector, of the same type as
296    /// VEC1/VEC2.  A VECTOR_SHUFFLE node also contains an array of constant int
297    /// values that indicate which value (or undef) each result element will
298    /// get.  These constant ints are accessible through the
299    /// ShuffleVectorSDNode class.  This is quite similar to the Altivec
300    /// 'vperm' instruction, except that the indices must be constants and are
301    /// in terms of the element size of VEC1/VEC2, not in terms of bytes.
302    VECTOR_SHUFFLE,
303
304    /// SCALAR_TO_VECTOR(VAL) - This represents the operation of loading a
305    /// scalar value into element 0 of the resultant vector type.  The top
306    /// elements 1 to N-1 of the N-element vector are undefined.  The type
307    /// of the operand must match the vector element type, except when they
308    /// are integer types.  In this case the operand is allowed to be wider
309    /// than the vector element type, and is implicitly truncated to it.
310    SCALAR_TO_VECTOR,
311
312    // MULHU/MULHS - Multiply high - Multiply two integers of type iN, producing
313    // an unsigned/signed value of type i[2*N], then return the top part.
314    MULHU, MULHS,
315
316    // Bitwise operators - logical and, logical or, logical xor, shift left,
317    // shift right algebraic (shift in sign bits), shift right logical (shift in
318    // zeroes), rotate left, rotate right, and byteswap.
319    AND, OR, XOR, SHL, SRA, SRL, ROTL, ROTR, BSWAP,
320
321    // Counting operators
322    CTTZ, CTLZ, CTPOP,
323
324    // Select(COND, TRUEVAL, FALSEVAL).  If the type of the boolean COND is not
325    // i1 then the high bits must conform to getBooleanContents.
326    SELECT,
327
328    // Select with condition operator - This selects between a true value and
329    // a false value (ops #2 and #3) based on the boolean result of comparing
330    // the lhs and rhs (ops #0 and #1) of a conditional expression with the
331    // condition code in op #4, a CondCodeSDNode.
332    SELECT_CC,
333
334    // SetCC operator - This evaluates to a true value iff the condition is
335    // true.  If the result value type is not i1 then the high bits conform
336    // to getBooleanContents.  The operands to this are the left and right
337    // operands to compare (ops #0, and #1) and the condition code to compare
338    // them with (op #2) as a CondCodeSDNode.
339    SETCC,
340
341    // RESULT = VSETCC(LHS, RHS, COND) operator - This evaluates to a vector of
342    // integer elements with all bits of the result elements set to true if the
343    // comparison is true or all cleared if the comparison is false.  The
344    // operands to this are the left and right operands to compare (LHS/RHS) and
345    // the condition code to compare them with (COND) as a CondCodeSDNode.
346    VSETCC,
347
348    // SHL_PARTS/SRA_PARTS/SRL_PARTS - These operators are used for expanded
349    // integer shift operations, just like ADD/SUB_PARTS.  The operation
350    // ordering is:
351    //       [Lo,Hi] = op [LoLHS,HiLHS], Amt
352    SHL_PARTS, SRA_PARTS, SRL_PARTS,
353
354    // Conversion operators.  These are all single input single output
355    // operations.  For all of these, the result type must be strictly
356    // wider or narrower (depending on the operation) than the source
357    // type.
358
359    // SIGN_EXTEND - Used for integer types, replicating the sign bit
360    // into new bits.
361    SIGN_EXTEND,
362
363    // ZERO_EXTEND - Used for integer types, zeroing the new bits.
364    ZERO_EXTEND,
365
366    // ANY_EXTEND - Used for integer types.  The high bits are undefined.
367    ANY_EXTEND,
368
369    // TRUNCATE - Completely drop the high bits.
370    TRUNCATE,
371
372    // [SU]INT_TO_FP - These operators convert integers (whose interpreted sign
373    // depends on the first letter) to floating point.
374    SINT_TO_FP,
375    UINT_TO_FP,
376
377    // SIGN_EXTEND_INREG - This operator atomically performs a SHL/SRA pair to
378    // sign extend a small value in a large integer register (e.g. sign
379    // extending the low 8 bits of a 32-bit register to fill the top 24 bits
380    // with the 7th bit).  The size of the smaller type is indicated by the 1th
381    // operand, a ValueType node.
382    SIGN_EXTEND_INREG,
383
384    /// FP_TO_[US]INT - Convert a floating point value to a signed or unsigned
385    /// integer.
386    FP_TO_SINT,
387    FP_TO_UINT,
388
389    /// X = FP_ROUND(Y, TRUNC) - Rounding 'Y' from a larger floating point type
390    /// down to the precision of the destination VT.  TRUNC is a flag, which is
391    /// always an integer that is zero or one.  If TRUNC is 0, this is a
392    /// normal rounding, if it is 1, this FP_ROUND is known to not change the
393    /// value of Y.
394    ///
395    /// The TRUNC = 1 case is used in cases where we know that the value will
396    /// not be modified by the node, because Y is not using any of the extra
397    /// precision of source type.  This allows certain transformations like
398    /// FP_EXTEND(FP_ROUND(X,1)) -> X which are not safe for
399    /// FP_EXTEND(FP_ROUND(X,0)) because the extra bits aren't removed.
400    FP_ROUND,
401
402    // FLT_ROUNDS_ - Returns current rounding mode:
403    // -1 Undefined
404    //  0 Round to 0
405    //  1 Round to nearest
406    //  2 Round to +inf
407    //  3 Round to -inf
408    FLT_ROUNDS_,
409
410    /// X = FP_ROUND_INREG(Y, VT) - This operator takes an FP register, and
411    /// rounds it to a floating point value.  It then promotes it and returns it
412    /// in a register of the same size.  This operation effectively just
413    /// discards excess precision.  The type to round down to is specified by
414    /// the VT operand, a VTSDNode.
415    FP_ROUND_INREG,
416
417    /// X = FP_EXTEND(Y) - Extend a smaller FP type into a larger FP type.
418    FP_EXTEND,
419
420    // BIT_CONVERT - This operator converts between integer, vector and FP
421    // values, as if the value was stored to memory with one type and loaded
422    // from the same address with the other type (or equivalently for vector
423    // format conversions, etc).  The source and result are required to have
424    // the same bit size (e.g.  f32 <-> i32).  This can also be used for
425    // int-to-int or fp-to-fp conversions, but that is a noop, deleted by
426    // getNode().
427    BIT_CONVERT,
428
429    // CONVERT_RNDSAT - This operator is used to support various conversions
430    // between various types (float, signed, unsigned and vectors of those
431    // types) with rounding and saturation. NOTE: Avoid using this operator as
432    // most target don't support it and the operator might be removed in the
433    // future. It takes the following arguments:
434    //   0) value
435    //   1) dest type (type to convert to)
436    //   2) src type (type to convert from)
437    //   3) rounding imm
438    //   4) saturation imm
439    //   5) ISD::CvtCode indicating the type of conversion to do
440    CONVERT_RNDSAT,
441
442    // FP16_TO_FP32, FP32_TO_FP16 - These operators are used to perform
443    // promotions and truncation for half-precision (16 bit) floating
444    // numbers. We need special nodes since FP16 is a storage-only type with
445    // special semantics of operations.
446    FP16_TO_FP32, FP32_TO_FP16,
447
448    // FNEG, FABS, FSQRT, FSIN, FCOS, FPOWI, FPOW,
449    // FLOG, FLOG2, FLOG10, FEXP, FEXP2,
450    // FCEIL, FTRUNC, FRINT, FNEARBYINT, FFLOOR - Perform various unary floating
451    // point operations. These are inspired by libm.
452    FNEG, FABS, FSQRT, FSIN, FCOS, FPOWI, FPOW,
453    FLOG, FLOG2, FLOG10, FEXP, FEXP2,
454    FCEIL, FTRUNC, FRINT, FNEARBYINT, FFLOOR,
455
456    // LOAD and STORE have token chains as their first operand, then the same
457    // operands as an LLVM load/store instruction, then an offset node that
458    // is added / subtracted from the base pointer to form the address (for
459    // indexed memory ops).
460    LOAD, STORE,
461
462    // DYNAMIC_STACKALLOC - Allocate some number of bytes on the stack aligned
463    // to a specified boundary.  This node always has two return values: a new
464    // stack pointer value and a chain. The first operand is the token chain,
465    // the second is the number of bytes to allocate, and the third is the
466    // alignment boundary.  The size is guaranteed to be a multiple of the stack
467    // alignment, and the alignment is guaranteed to be bigger than the stack
468    // alignment (if required) or 0 to get standard stack alignment.
469    DYNAMIC_STACKALLOC,
470
471    // Control flow instructions.  These all have token chains.
472
473    // BR - Unconditional branch.  The first operand is the chain
474    // operand, the second is the MBB to branch to.
475    BR,
476
477    // BRIND - Indirect branch.  The first operand is the chain, the second
478    // is the value to branch to, which must be of the same type as the target's
479    // pointer type.
480    BRIND,
481
482    // BR_JT - Jumptable branch. The first operand is the chain, the second
483    // is the jumptable index, the last one is the jumptable entry index.
484    BR_JT,
485
486    // BRCOND - Conditional branch.  The first operand is the chain, the
487    // second is the condition, the third is the block to branch to if the
488    // condition is true.  If the type of the condition is not i1, then the
489    // high bits must conform to getBooleanContents.
490    BRCOND,
491
492    // BR_CC - Conditional branch.  The behavior is like that of SELECT_CC, in
493    // that the condition is represented as condition code, and two nodes to
494    // compare, rather than as a combined SetCC node.  The operands in order are
495    // chain, cc, lhs, rhs, block to branch to if condition is true.
496    BR_CC,
497
498    // INLINEASM - Represents an inline asm block.  This node always has two
499    // return values: a chain and a flag result.  The inputs are as follows:
500    //   Operand #0   : Input chain.
501    //   Operand #1   : a ExternalSymbolSDNode with a pointer to the asm string.
502    //   Operand #2n+2: A RegisterNode.
503    //   Operand #2n+3: A TargetConstant, indicating if the reg is a use/def
504    //   Operand #last: Optional, an incoming flag.
505    INLINEASM,
506
507    // EH_LABEL - Represents a label in mid basic block used to track
508    // locations needed for debug and exception handling tables.  These nodes
509    // take a chain as input and return a chain.
510    EH_LABEL,
511
512    // STACKSAVE - STACKSAVE has one operand, an input chain.  It produces a
513    // value, the same type as the pointer type for the system, and an output
514    // chain.
515    STACKSAVE,
516
517    // STACKRESTORE has two operands, an input chain and a pointer to restore to
518    // it returns an output chain.
519    STACKRESTORE,
520
521    // CALLSEQ_START/CALLSEQ_END - These operators mark the beginning and end of
522    // a call sequence, and carry arbitrary information that target might want
523    // to know.  The first operand is a chain, the rest are specified by the
524    // target and not touched by the DAG optimizers.
525    // CALLSEQ_START..CALLSEQ_END pairs may not be nested.
526    CALLSEQ_START,  // Beginning of a call sequence
527    CALLSEQ_END,    // End of a call sequence
528
529    // VAARG - VAARG has three operands: an input chain, a pointer, and a
530    // SRCVALUE.  It returns a pair of values: the vaarg value and a new chain.
531    VAARG,
532
533    // VACOPY - VACOPY has five operands: an input chain, a destination pointer,
534    // a source pointer, a SRCVALUE for the destination, and a SRCVALUE for the
535    // source.
536    VACOPY,
537
538    // VAEND, VASTART - VAEND and VASTART have three operands: an input chain, a
539    // pointer, and a SRCVALUE.
540    VAEND, VASTART,
541
542    // SRCVALUE - This is a node type that holds a Value* that is used to
543    // make reference to a value in the LLVM IR.
544    SRCVALUE,
545
546    // PCMARKER - This corresponds to the pcmarker intrinsic.
547    PCMARKER,
548
549    // READCYCLECOUNTER - This corresponds to the readcyclecounter intrinsic.
550    // The only operand is a chain and a value and a chain are produced.  The
551    // value is the contents of the architecture specific cycle counter like
552    // register (or other high accuracy low latency clock source)
553    READCYCLECOUNTER,
554
555    // HANDLENODE node - Used as a handle for various purposes.
556    HANDLENODE,
557
558    // TRAMPOLINE - This corresponds to the init_trampoline intrinsic.
559    // It takes as input a token chain, the pointer to the trampoline,
560    // the pointer to the nested function, the pointer to pass for the
561    // 'nest' parameter, a SRCVALUE for the trampoline and another for
562    // the nested function (allowing targets to access the original
563    // Function*).  It produces the result of the intrinsic and a token
564    // chain as output.
565    TRAMPOLINE,
566
567    // TRAP - Trapping instruction
568    TRAP,
569
570    // PREFETCH - This corresponds to a prefetch intrinsic. It takes chains are
571    // their first operand. The other operands are the address to prefetch,
572    // read / write specifier, and locality specifier.
573    PREFETCH,
574
575    // OUTCHAIN = MEMBARRIER(INCHAIN, load-load, load-store, store-load,
576    //                       store-store, device)
577    // This corresponds to the memory.barrier intrinsic.
578    // it takes an input chain, 4 operands to specify the type of barrier, an
579    // operand specifying if the barrier applies to device and uncached memory
580    // and produces an output chain.
581    MEMBARRIER,
582
583    // Val, OUTCHAIN = ATOMIC_CMP_SWAP(INCHAIN, ptr, cmp, swap)
584    // this corresponds to the atomic.lcs intrinsic.
585    // cmp is compared to *ptr, and if equal, swap is stored in *ptr.
586    // the return is always the original value in *ptr
587    ATOMIC_CMP_SWAP,
588
589    // Val, OUTCHAIN = ATOMIC_SWAP(INCHAIN, ptr, amt)
590    // this corresponds to the atomic.swap intrinsic.
591    // amt is stored to *ptr atomically.
592    // the return is always the original value in *ptr
593    ATOMIC_SWAP,
594
595    // Val, OUTCHAIN = ATOMIC_LOAD_[OpName](INCHAIN, ptr, amt)
596    // this corresponds to the atomic.load.[OpName] intrinsic.
597    // op(*ptr, amt) is stored to *ptr atomically.
598    // the return is always the original value in *ptr
599    ATOMIC_LOAD_ADD,
600    ATOMIC_LOAD_SUB,
601    ATOMIC_LOAD_AND,
602    ATOMIC_LOAD_OR,
603    ATOMIC_LOAD_XOR,
604    ATOMIC_LOAD_NAND,
605    ATOMIC_LOAD_MIN,
606    ATOMIC_LOAD_MAX,
607    ATOMIC_LOAD_UMIN,
608    ATOMIC_LOAD_UMAX,
609
610    /// BUILTIN_OP_END - This must be the last enum value in this list.
611    /// The target-specific pre-isel opcode values start here.
612    BUILTIN_OP_END
613  };
614
615  /// FIRST_TARGET_MEMORY_OPCODE - Target-specific pre-isel operations
616  /// which do not reference a specific memory location should be less than
617  /// this value. Those that do must not be less than this value, and can
618  /// be used with SelectionDAG::getMemIntrinsicNode.
619  static const int FIRST_TARGET_MEMORY_OPCODE = BUILTIN_OP_END+100;
620
621  /// Node predicates
622
623  /// isBuildVectorAllOnes - Return true if the specified node is a
624  /// BUILD_VECTOR where all of the elements are ~0 or undef.
625  bool isBuildVectorAllOnes(const SDNode *N);
626
627  /// isBuildVectorAllZeros - Return true if the specified node is a
628  /// BUILD_VECTOR where all of the elements are 0 or undef.
629  bool isBuildVectorAllZeros(const SDNode *N);
630
631  /// isScalarToVector - Return true if the specified node is a
632  /// ISD::SCALAR_TO_VECTOR node or a BUILD_VECTOR node where only the low
633  /// element is not an undef.
634  bool isScalarToVector(const SDNode *N);
635
636  //===--------------------------------------------------------------------===//
637  /// MemIndexedMode enum - This enum defines the load / store indexed
638  /// addressing modes.
639  ///
640  /// UNINDEXED    "Normal" load / store. The effective address is already
641  ///              computed and is available in the base pointer. The offset
642  ///              operand is always undefined. In addition to producing a
643  ///              chain, an unindexed load produces one value (result of the
644  ///              load); an unindexed store does not produce a value.
645  ///
646  /// PRE_INC      Similar to the unindexed mode where the effective address is
647  /// PRE_DEC      the value of the base pointer add / subtract the offset.
648  ///              It considers the computation as being folded into the load /
649  ///              store operation (i.e. the load / store does the address
650  ///              computation as well as performing the memory transaction).
651  ///              The base operand is always undefined. In addition to
652  ///              producing a chain, pre-indexed load produces two values
653  ///              (result of the load and the result of the address
654  ///              computation); a pre-indexed store produces one value (result
655  ///              of the address computation).
656  ///
657  /// POST_INC     The effective address is the value of the base pointer. The
658  /// POST_DEC     value of the offset operand is then added to / subtracted
659  ///              from the base after memory transaction. In addition to
660  ///              producing a chain, post-indexed load produces two values
661  ///              (the result of the load and the result of the base +/- offset
662  ///              computation); a post-indexed store produces one value (the
663  ///              the result of the base +/- offset computation).
664  ///
665  enum MemIndexedMode {
666    UNINDEXED = 0,
667    PRE_INC,
668    PRE_DEC,
669    POST_INC,
670    POST_DEC,
671    LAST_INDEXED_MODE
672  };
673
674  //===--------------------------------------------------------------------===//
675  /// LoadExtType enum - This enum defines the three variants of LOADEXT
676  /// (load with extension).
677  ///
678  /// SEXTLOAD loads the integer operand and sign extends it to a larger
679  ///          integer result type.
680  /// ZEXTLOAD loads the integer operand and zero extends it to a larger
681  ///          integer result type.
682  /// EXTLOAD  is used for three things: floating point extending loads,
683  ///          integer extending loads [the top bits are undefined], and vector
684  ///          extending loads [load into low elt].
685  ///
686  enum LoadExtType {
687    NON_EXTLOAD = 0,
688    EXTLOAD,
689    SEXTLOAD,
690    ZEXTLOAD,
691    LAST_LOADEXT_TYPE
692  };
693
694  //===--------------------------------------------------------------------===//
695  /// ISD::CondCode enum - These are ordered carefully to make the bitfields
696  /// below work out, when considering SETFALSE (something that never exists
697  /// dynamically) as 0.  "U" -> Unsigned (for integer operands) or Unordered
698  /// (for floating point), "L" -> Less than, "G" -> Greater than, "E" -> Equal
699  /// to.  If the "N" column is 1, the result of the comparison is undefined if
700  /// the input is a NAN.
701  ///
702  /// All of these (except for the 'always folded ops') should be handled for
703  /// floating point.  For integer, only the SETEQ,SETNE,SETLT,SETLE,SETGT,
704  /// SETGE,SETULT,SETULE,SETUGT, and SETUGE opcodes are used.
705  ///
706  /// Note that these are laid out in a specific order to allow bit-twiddling
707  /// to transform conditions.
708  enum CondCode {
709    // Opcode          N U L G E       Intuitive operation
710    SETFALSE,      //    0 0 0 0       Always false (always folded)
711    SETOEQ,        //    0 0 0 1       True if ordered and equal
712    SETOGT,        //    0 0 1 0       True if ordered and greater than
713    SETOGE,        //    0 0 1 1       True if ordered and greater than or equal
714    SETOLT,        //    0 1 0 0       True if ordered and less than
715    SETOLE,        //    0 1 0 1       True if ordered and less than or equal
716    SETONE,        //    0 1 1 0       True if ordered and operands are unequal
717    SETO,          //    0 1 1 1       True if ordered (no nans)
718    SETUO,         //    1 0 0 0       True if unordered: isnan(X) | isnan(Y)
719    SETUEQ,        //    1 0 0 1       True if unordered or equal
720    SETUGT,        //    1 0 1 0       True if unordered or greater than
721    SETUGE,        //    1 0 1 1       True if unordered, greater than, or equal
722    SETULT,        //    1 1 0 0       True if unordered or less than
723    SETULE,        //    1 1 0 1       True if unordered, less than, or equal
724    SETUNE,        //    1 1 1 0       True if unordered or not equal
725    SETTRUE,       //    1 1 1 1       Always true (always folded)
726    // Don't care operations: undefined if the input is a nan.
727    SETFALSE2,     //  1 X 0 0 0       Always false (always folded)
728    SETEQ,         //  1 X 0 0 1       True if equal
729    SETGT,         //  1 X 0 1 0       True if greater than
730    SETGE,         //  1 X 0 1 1       True if greater than or equal
731    SETLT,         //  1 X 1 0 0       True if less than
732    SETLE,         //  1 X 1 0 1       True if less than or equal
733    SETNE,         //  1 X 1 1 0       True if not equal
734    SETTRUE2,      //  1 X 1 1 1       Always true (always folded)
735
736    SETCC_INVALID       // Marker value.
737  };
738
739  /// isSignedIntSetCC - Return true if this is a setcc instruction that
740  /// performs a signed comparison when used with integer operands.
741  inline bool isSignedIntSetCC(CondCode Code) {
742    return Code == SETGT || Code == SETGE || Code == SETLT || Code == SETLE;
743  }
744
745  /// isUnsignedIntSetCC - Return true if this is a setcc instruction that
746  /// performs an unsigned comparison when used with integer operands.
747  inline bool isUnsignedIntSetCC(CondCode Code) {
748    return Code == SETUGT || Code == SETUGE || Code == SETULT || Code == SETULE;
749  }
750
751  /// isTrueWhenEqual - Return true if the specified condition returns true if
752  /// the two operands to the condition are equal.  Note that if one of the two
753  /// operands is a NaN, this value is meaningless.
754  inline bool isTrueWhenEqual(CondCode Cond) {
755    return ((int)Cond & 1) != 0;
756  }
757
758  /// getUnorderedFlavor - This function returns 0 if the condition is always
759  /// false if an operand is a NaN, 1 if the condition is always true if the
760  /// operand is a NaN, and 2 if the condition is undefined if the operand is a
761  /// NaN.
762  inline unsigned getUnorderedFlavor(CondCode Cond) {
763    return ((int)Cond >> 3) & 3;
764  }
765
766  /// getSetCCInverse - Return the operation corresponding to !(X op Y), where
767  /// 'op' is a valid SetCC operation.
768  CondCode getSetCCInverse(CondCode Operation, bool isInteger);
769
770  /// getSetCCSwappedOperands - Return the operation corresponding to (Y op X)
771  /// when given the operation for (X op Y).
772  CondCode getSetCCSwappedOperands(CondCode Operation);
773
774  /// getSetCCOrOperation - Return the result of a logical OR between different
775  /// comparisons of identical values: ((X op1 Y) | (X op2 Y)).  This
776  /// function returns SETCC_INVALID if it is not possible to represent the
777  /// resultant comparison.
778  CondCode getSetCCOrOperation(CondCode Op1, CondCode Op2, bool isInteger);
779
780  /// getSetCCAndOperation - Return the result of a logical AND between
781  /// different comparisons of identical values: ((X op1 Y) & (X op2 Y)).  This
782  /// function returns SETCC_INVALID if it is not possible to represent the
783  /// resultant comparison.
784  CondCode getSetCCAndOperation(CondCode Op1, CondCode Op2, bool isInteger);
785
786  //===--------------------------------------------------------------------===//
787  /// CvtCode enum - This enum defines the various converts CONVERT_RNDSAT
788  /// supports.
789  enum CvtCode {
790    CVT_FF,     // Float from Float
791    CVT_FS,     // Float from Signed
792    CVT_FU,     // Float from Unsigned
793    CVT_SF,     // Signed from Float
794    CVT_UF,     // Unsigned from Float
795    CVT_SS,     // Signed from Signed
796    CVT_SU,     // Signed from Unsigned
797    CVT_US,     // Unsigned from Signed
798    CVT_UU,     // Unsigned from Unsigned
799    CVT_INVALID // Marker - Invalid opcode
800  };
801}  // end llvm::ISD namespace
802
803
804//===----------------------------------------------------------------------===//
805/// SDValue - Unlike LLVM values, Selection DAG nodes may return multiple
806/// values as the result of a computation.  Many nodes return multiple values,
807/// from loads (which define a token and a return value) to ADDC (which returns
808/// a result and a carry value), to calls (which may return an arbitrary number
809/// of values).
810///
811/// As such, each use of a SelectionDAG computation must indicate the node that
812/// computes it as well as which return value to use from that node.  This pair
813/// of information is represented with the SDValue value type.
814///
815class SDValue {
816  SDNode *Node;       // The node defining the value we are using.
817  unsigned ResNo;     // Which return value of the node we are using.
818public:
819  SDValue() : Node(0), ResNo(0) {}
820  SDValue(SDNode *node, unsigned resno) : Node(node), ResNo(resno) {}
821
822  /// get the index which selects a specific result in the SDNode
823  unsigned getResNo() const { return ResNo; }
824
825  /// get the SDNode which holds the desired result
826  SDNode *getNode() const { return Node; }
827
828  /// set the SDNode
829  void setNode(SDNode *N) { Node = N; }
830
831  inline SDNode *operator->() const { return Node; }
832
833  bool operator==(const SDValue &O) const {
834    return Node == O.Node && ResNo == O.ResNo;
835  }
836  bool operator!=(const SDValue &O) const {
837    return !operator==(O);
838  }
839  bool operator<(const SDValue &O) const {
840    return Node < O.Node || (Node == O.Node && ResNo < O.ResNo);
841  }
842
843  SDValue getValue(unsigned R) const {
844    return SDValue(Node, R);
845  }
846
847  // isOperandOf - Return true if this node is an operand of N.
848  bool isOperandOf(SDNode *N) const;
849
850  /// getValueType - Return the ValueType of the referenced return value.
851  ///
852  inline EVT getValueType() const;
853
854  /// getValueSizeInBits - Returns the size of the value in bits.
855  ///
856  unsigned getValueSizeInBits() const {
857    return getValueType().getSizeInBits();
858  }
859
860  // Forwarding methods - These forward to the corresponding methods in SDNode.
861  inline unsigned getOpcode() const;
862  inline unsigned getNumOperands() const;
863  inline const SDValue &getOperand(unsigned i) const;
864  inline uint64_t getConstantOperandVal(unsigned i) const;
865  inline bool isTargetMemoryOpcode() const;
866  inline bool isTargetOpcode() const;
867  inline bool isMachineOpcode() const;
868  inline unsigned getMachineOpcode() const;
869  inline const DebugLoc getDebugLoc() const;
870
871
872  /// reachesChainWithoutSideEffects - Return true if this operand (which must
873  /// be a chain) reaches the specified operand without crossing any
874  /// side-effecting instructions.  In practice, this looks through token
875  /// factors and non-volatile loads.  In order to remain efficient, this only
876  /// looks a couple of nodes in, it does not do an exhaustive search.
877  bool reachesChainWithoutSideEffects(SDValue Dest,
878                                      unsigned Depth = 2) const;
879
880  /// use_empty - Return true if there are no nodes using value ResNo
881  /// of Node.
882  ///
883  inline bool use_empty() const;
884
885  /// hasOneUse - Return true if there is exactly one node using value
886  /// ResNo of Node.
887  ///
888  inline bool hasOneUse() const;
889};
890
891
892template<> struct DenseMapInfo<SDValue> {
893  static inline SDValue getEmptyKey() {
894    return SDValue((SDNode*)-1, -1U);
895  }
896  static inline SDValue getTombstoneKey() {
897    return SDValue((SDNode*)-1, 0);
898  }
899  static unsigned getHashValue(const SDValue &Val) {
900    return ((unsigned)((uintptr_t)Val.getNode() >> 4) ^
901            (unsigned)((uintptr_t)Val.getNode() >> 9)) + Val.getResNo();
902  }
903  static bool isEqual(const SDValue &LHS, const SDValue &RHS) {
904    return LHS == RHS;
905  }
906};
907template <> struct isPodLike<SDValue> { static const bool value = true; };
908
909
910/// simplify_type specializations - Allow casting operators to work directly on
911/// SDValues as if they were SDNode*'s.
912template<> struct simplify_type<SDValue> {
913  typedef SDNode* SimpleType;
914  static SimpleType getSimplifiedValue(const SDValue &Val) {
915    return static_cast<SimpleType>(Val.getNode());
916  }
917};
918template<> struct simplify_type<const SDValue> {
919  typedef SDNode* SimpleType;
920  static SimpleType getSimplifiedValue(const SDValue &Val) {
921    return static_cast<SimpleType>(Val.getNode());
922  }
923};
924
925/// SDUse - Represents a use of a SDNode. This class holds an SDValue,
926/// which records the SDNode being used and the result number, a
927/// pointer to the SDNode using the value, and Next and Prev pointers,
928/// which link together all the uses of an SDNode.
929///
930class SDUse {
931  /// Val - The value being used.
932  SDValue Val;
933  /// User - The user of this value.
934  SDNode *User;
935  /// Prev, Next - Pointers to the uses list of the SDNode referred by
936  /// this operand.
937  SDUse **Prev, *Next;
938
939  SDUse(const SDUse &U);          // Do not implement
940  void operator=(const SDUse &U); // Do not implement
941
942public:
943  SDUse() : Val(), User(NULL), Prev(NULL), Next(NULL) {}
944
945  /// Normally SDUse will just implicitly convert to an SDValue that it holds.
946  operator const SDValue&() const { return Val; }
947
948  /// If implicit conversion to SDValue doesn't work, the get() method returns
949  /// the SDValue.
950  const SDValue &get() const { return Val; }
951
952  /// getUser - This returns the SDNode that contains this Use.
953  SDNode *getUser() { return User; }
954
955  /// getNext - Get the next SDUse in the use list.
956  SDUse *getNext() const { return Next; }
957
958  /// getNode - Convenience function for get().getNode().
959  SDNode *getNode() const { return Val.getNode(); }
960  /// getResNo - Convenience function for get().getResNo().
961  unsigned getResNo() const { return Val.getResNo(); }
962  /// getValueType - Convenience function for get().getValueType().
963  EVT getValueType() const { return Val.getValueType(); }
964
965  /// operator== - Convenience function for get().operator==
966  bool operator==(const SDValue &V) const {
967    return Val == V;
968  }
969
970  /// operator!= - Convenience function for get().operator!=
971  bool operator!=(const SDValue &V) const {
972    return Val != V;
973  }
974
975  /// operator< - Convenience function for get().operator<
976  bool operator<(const SDValue &V) const {
977    return Val < V;
978  }
979
980private:
981  friend class SelectionDAG;
982  friend class SDNode;
983
984  void setUser(SDNode *p) { User = p; }
985
986  /// set - Remove this use from its existing use list, assign it the
987  /// given value, and add it to the new value's node's use list.
988  inline void set(const SDValue &V);
989  /// setInitial - like set, but only supports initializing a newly-allocated
990  /// SDUse with a non-null value.
991  inline void setInitial(const SDValue &V);
992  /// setNode - like set, but only sets the Node portion of the value,
993  /// leaving the ResNo portion unmodified.
994  inline void setNode(SDNode *N);
995
996  void addToList(SDUse **List) {
997    Next = *List;
998    if (Next) Next->Prev = &Next;
999    Prev = List;
1000    *List = this;
1001  }
1002
1003  void removeFromList() {
1004    *Prev = Next;
1005    if (Next) Next->Prev = Prev;
1006  }
1007};
1008
1009/// simplify_type specializations - Allow casting operators to work directly on
1010/// SDValues as if they were SDNode*'s.
1011template<> struct simplify_type<SDUse> {
1012  typedef SDNode* SimpleType;
1013  static SimpleType getSimplifiedValue(const SDUse &Val) {
1014    return static_cast<SimpleType>(Val.getNode());
1015  }
1016};
1017template<> struct simplify_type<const SDUse> {
1018  typedef SDNode* SimpleType;
1019  static SimpleType getSimplifiedValue(const SDUse &Val) {
1020    return static_cast<SimpleType>(Val.getNode());
1021  }
1022};
1023
1024
1025/// SDNode - Represents one node in the SelectionDAG.
1026///
1027class SDNode : public FoldingSetNode, public ilist_node<SDNode> {
1028private:
1029  /// NodeType - The operation that this node performs.
1030  ///
1031  int16_t NodeType;
1032
1033  /// OperandsNeedDelete - This is true if OperandList was new[]'d.  If true,
1034  /// then they will be delete[]'d when the node is destroyed.
1035  uint16_t OperandsNeedDelete : 1;
1036
1037  /// HasDebugValue - This tracks whether this node has one or more dbg_value
1038  /// nodes corresponding to it.
1039  uint16_t HasDebugValue : 1;
1040
1041protected:
1042  /// SubclassData - This member is defined by this class, but is not used for
1043  /// anything.  Subclasses can use it to hold whatever state they find useful.
1044  /// This field is initialized to zero by the ctor.
1045  uint16_t SubclassData : 14;
1046
1047private:
1048  /// NodeId - Unique id per SDNode in the DAG.
1049  int NodeId;
1050
1051  /// OperandList - The values that are used by this operation.
1052  ///
1053  SDUse *OperandList;
1054
1055  /// ValueList - The types of the values this node defines.  SDNode's may
1056  /// define multiple values simultaneously.
1057  const EVT *ValueList;
1058
1059  /// UseList - List of uses for this SDNode.
1060  SDUse *UseList;
1061
1062  /// NumOperands/NumValues - The number of entries in the Operand/Value list.
1063  unsigned short NumOperands, NumValues;
1064
1065  /// debugLoc - source line information.
1066  DebugLoc debugLoc;
1067
1068  /// getValueTypeList - Return a pointer to the specified value type.
1069  static const EVT *getValueTypeList(EVT VT);
1070
1071  friend class SelectionDAG;
1072  friend struct ilist_traits<SDNode>;
1073
1074public:
1075  //===--------------------------------------------------------------------===//
1076  //  Accessors
1077  //
1078
1079  /// getOpcode - Return the SelectionDAG opcode value for this node. For
1080  /// pre-isel nodes (those for which isMachineOpcode returns false), these
1081  /// are the opcode values in the ISD and <target>ISD namespaces. For
1082  /// post-isel opcodes, see getMachineOpcode.
1083  unsigned getOpcode()  const { return (unsigned short)NodeType; }
1084
1085  /// isTargetOpcode - Test if this node has a target-specific opcode (in the
1086  /// \<target\>ISD namespace).
1087  bool isTargetOpcode() const { return NodeType >= ISD::BUILTIN_OP_END; }
1088
1089  /// isTargetMemoryOpcode - Test if this node has a target-specific
1090  /// memory-referencing opcode (in the \<target\>ISD namespace and
1091  /// greater than FIRST_TARGET_MEMORY_OPCODE).
1092  bool isTargetMemoryOpcode() const {
1093    return NodeType >= ISD::FIRST_TARGET_MEMORY_OPCODE;
1094  }
1095
1096  /// isMachineOpcode - Test if this node has a post-isel opcode, directly
1097  /// corresponding to a MachineInstr opcode.
1098  bool isMachineOpcode() const { return NodeType < 0; }
1099
1100  /// getMachineOpcode - This may only be called if isMachineOpcode returns
1101  /// true. It returns the MachineInstr opcode value that the node's opcode
1102  /// corresponds to.
1103  unsigned getMachineOpcode() const {
1104    assert(isMachineOpcode() && "Not a MachineInstr opcode!");
1105    return ~NodeType;
1106  }
1107
1108  /// getHasDebugValue - get this bit.
1109  bool getHasDebugValue() const { return HasDebugValue; }
1110
1111  /// setHasDebugValue - set this bit.
1112  void setHasDebugValue(bool b) { HasDebugValue = b; }
1113
1114  /// use_empty - Return true if there are no uses of this node.
1115  ///
1116  bool use_empty() const { return UseList == NULL; }
1117
1118  /// hasOneUse - Return true if there is exactly one use of this node.
1119  ///
1120  bool hasOneUse() const {
1121    return !use_empty() && llvm::next(use_begin()) == use_end();
1122  }
1123
1124  /// use_size - Return the number of uses of this node. This method takes
1125  /// time proportional to the number of uses.
1126  ///
1127  size_t use_size() const { return std::distance(use_begin(), use_end()); }
1128
1129  /// getNodeId - Return the unique node id.
1130  ///
1131  int getNodeId() const { return NodeId; }
1132
1133  /// setNodeId - Set unique node id.
1134  void setNodeId(int Id) { NodeId = Id; }
1135
1136  /// getDebugLoc - Return the source location info.
1137  const DebugLoc getDebugLoc() const { return debugLoc; }
1138
1139  /// setDebugLoc - Set source location info.  Try to avoid this, putting
1140  /// it in the constructor is preferable.
1141  void setDebugLoc(const DebugLoc dl) { debugLoc = dl; }
1142
1143  /// use_iterator - This class provides iterator support for SDUse
1144  /// operands that use a specific SDNode.
1145  class use_iterator
1146    : public std::iterator<std::forward_iterator_tag, SDUse, ptrdiff_t> {
1147    SDUse *Op;
1148    explicit use_iterator(SDUse *op) : Op(op) {
1149    }
1150    friend class SDNode;
1151  public:
1152    typedef std::iterator<std::forward_iterator_tag,
1153                          SDUse, ptrdiff_t>::reference reference;
1154    typedef std::iterator<std::forward_iterator_tag,
1155                          SDUse, ptrdiff_t>::pointer pointer;
1156
1157    use_iterator(const use_iterator &I) : Op(I.Op) {}
1158    use_iterator() : Op(0) {}
1159
1160    bool operator==(const use_iterator &x) const {
1161      return Op == x.Op;
1162    }
1163    bool operator!=(const use_iterator &x) const {
1164      return !operator==(x);
1165    }
1166
1167    /// atEnd - return true if this iterator is at the end of uses list.
1168    bool atEnd() const { return Op == 0; }
1169
1170    // Iterator traversal: forward iteration only.
1171    use_iterator &operator++() {          // Preincrement
1172      assert(Op && "Cannot increment end iterator!");
1173      Op = Op->getNext();
1174      return *this;
1175    }
1176
1177    use_iterator operator++(int) {        // Postincrement
1178      use_iterator tmp = *this; ++*this; return tmp;
1179    }
1180
1181    /// Retrieve a pointer to the current user node.
1182    SDNode *operator*() const {
1183      assert(Op && "Cannot dereference end iterator!");
1184      return Op->getUser();
1185    }
1186
1187    SDNode *operator->() const { return operator*(); }
1188
1189    SDUse &getUse() const { return *Op; }
1190
1191    /// getOperandNo - Retrieve the operand # of this use in its user.
1192    ///
1193    unsigned getOperandNo() const {
1194      assert(Op && "Cannot dereference end iterator!");
1195      return (unsigned)(Op - Op->getUser()->OperandList);
1196    }
1197  };
1198
1199  /// use_begin/use_end - Provide iteration support to walk over all uses
1200  /// of an SDNode.
1201
1202  use_iterator use_begin() const {
1203    return use_iterator(UseList);
1204  }
1205
1206  static use_iterator use_end() { return use_iterator(0); }
1207
1208
1209  /// hasNUsesOfValue - Return true if there are exactly NUSES uses of the
1210  /// indicated value.  This method ignores uses of other values defined by this
1211  /// operation.
1212  bool hasNUsesOfValue(unsigned NUses, unsigned Value) const;
1213
1214  /// hasAnyUseOfValue - Return true if there are any use of the indicated
1215  /// value. This method ignores uses of other values defined by this operation.
1216  bool hasAnyUseOfValue(unsigned Value) const;
1217
1218  /// isOnlyUserOf - Return true if this node is the only use of N.
1219  ///
1220  bool isOnlyUserOf(SDNode *N) const;
1221
1222  /// isOperandOf - Return true if this node is an operand of N.
1223  ///
1224  bool isOperandOf(SDNode *N) const;
1225
1226  /// isPredecessorOf - Return true if this node is a predecessor of N. This
1227  /// node is either an operand of N or it can be reached by recursively
1228  /// traversing up the operands.
1229  /// NOTE: this is an expensive method. Use it carefully.
1230  bool isPredecessorOf(SDNode *N) const;
1231
1232  /// getNumOperands - Return the number of values used by this operation.
1233  ///
1234  unsigned getNumOperands() const { return NumOperands; }
1235
1236  /// getConstantOperandVal - Helper method returns the integer value of a
1237  /// ConstantSDNode operand.
1238  uint64_t getConstantOperandVal(unsigned Num) const;
1239
1240  const SDValue &getOperand(unsigned Num) const {
1241    assert(Num < NumOperands && "Invalid child # of SDNode!");
1242    return OperandList[Num];
1243  }
1244
1245  typedef SDUse* op_iterator;
1246  op_iterator op_begin() const { return OperandList; }
1247  op_iterator op_end() const { return OperandList+NumOperands; }
1248
1249  SDVTList getVTList() const {
1250    SDVTList X = { ValueList, NumValues };
1251    return X;
1252  }
1253
1254  /// getFlaggedNode - If this node has a flag operand, return the node
1255  /// to which the flag operand points. Otherwise return NULL.
1256  SDNode *getFlaggedNode() const {
1257    if (getNumOperands() != 0 &&
1258      getOperand(getNumOperands()-1).getValueType().getSimpleVT() == MVT::Flag)
1259      return getOperand(getNumOperands()-1).getNode();
1260    return 0;
1261  }
1262
1263  // If this is a pseudo op, like copyfromreg, look to see if there is a
1264  // real target node flagged to it.  If so, return the target node.
1265  const SDNode *getFlaggedMachineNode() const {
1266    const SDNode *FoundNode = this;
1267
1268    // Climb up flag edges until a machine-opcode node is found, or the
1269    // end of the chain is reached.
1270    while (!FoundNode->isMachineOpcode()) {
1271      const SDNode *N = FoundNode->getFlaggedNode();
1272      if (!N) break;
1273      FoundNode = N;
1274    }
1275
1276    return FoundNode;
1277  }
1278
1279  /// getNumValues - Return the number of values defined/returned by this
1280  /// operator.
1281  ///
1282  unsigned getNumValues() const { return NumValues; }
1283
1284  /// getValueType - Return the type of a specified result.
1285  ///
1286  EVT getValueType(unsigned ResNo) const {
1287    assert(ResNo < NumValues && "Illegal result number!");
1288    return ValueList[ResNo];
1289  }
1290
1291  /// getValueSizeInBits - Returns MVT::getSizeInBits(getValueType(ResNo)).
1292  ///
1293  unsigned getValueSizeInBits(unsigned ResNo) const {
1294    return getValueType(ResNo).getSizeInBits();
1295  }
1296
1297  typedef const EVT* value_iterator;
1298  value_iterator value_begin() const { return ValueList; }
1299  value_iterator value_end() const { return ValueList+NumValues; }
1300
1301  /// getOperationName - Return the opcode of this operation for printing.
1302  ///
1303  std::string getOperationName(const SelectionDAG *G = 0) const;
1304  static const char* getIndexedModeName(ISD::MemIndexedMode AM);
1305  void print_types(raw_ostream &OS, const SelectionDAG *G) const;
1306  void print_details(raw_ostream &OS, const SelectionDAG *G) const;
1307  void print(raw_ostream &OS, const SelectionDAG *G = 0) const;
1308  void printr(raw_ostream &OS, const SelectionDAG *G = 0) const;
1309
1310  /// printrFull - Print a SelectionDAG node and all children down to
1311  /// the leaves.  The given SelectionDAG allows target-specific nodes
1312  /// to be printed in human-readable form.  Unlike printr, this will
1313  /// print the whole DAG, including children that appear multiple
1314  /// times.
1315  ///
1316  void printrFull(raw_ostream &O, const SelectionDAG *G = 0) const;
1317
1318  /// printrWithDepth - Print a SelectionDAG node and children up to
1319  /// depth "depth."  The given SelectionDAG allows target-specific
1320  /// nodes to be printed in human-readable form.  Unlike printr, this
1321  /// will print children that appear multiple times wherever they are
1322  /// used.
1323  ///
1324  void printrWithDepth(raw_ostream &O, const SelectionDAG *G = 0,
1325                       unsigned depth = 100) const;
1326
1327
1328  /// dump - Dump this node, for debugging.
1329  void dump() const;
1330
1331  /// dumpr - Dump (recursively) this node and its use-def subgraph.
1332  void dumpr() const;
1333
1334  /// dump - Dump this node, for debugging.
1335  /// The given SelectionDAG allows target-specific nodes to be printed
1336  /// in human-readable form.
1337  void dump(const SelectionDAG *G) const;
1338
1339  /// dumpr - Dump (recursively) this node and its use-def subgraph.
1340  /// The given SelectionDAG allows target-specific nodes to be printed
1341  /// in human-readable form.
1342  void dumpr(const SelectionDAG *G) const;
1343
1344  /// dumprFull - printrFull to dbgs().  The given SelectionDAG allows
1345  /// target-specific nodes to be printed in human-readable form.
1346  /// Unlike dumpr, this will print the whole DAG, including children
1347  /// that appear multiple times.
1348  ///
1349  void dumprFull(const SelectionDAG *G = 0) const;
1350
1351  /// dumprWithDepth - printrWithDepth to dbgs().  The given
1352  /// SelectionDAG allows target-specific nodes to be printed in
1353  /// human-readable form.  Unlike dumpr, this will print children
1354  /// that appear multiple times wherever they are used.
1355  ///
1356  void dumprWithDepth(const SelectionDAG *G = 0, unsigned depth = 100) const;
1357
1358
1359  static bool classof(const SDNode *) { return true; }
1360
1361  /// Profile - Gather unique data for the node.
1362  ///
1363  void Profile(FoldingSetNodeID &ID) const;
1364
1365  /// addUse - This method should only be used by the SDUse class.
1366  ///
1367  void addUse(SDUse &U) { U.addToList(&UseList); }
1368
1369protected:
1370  static SDVTList getSDVTList(EVT VT) {
1371    SDVTList Ret = { getValueTypeList(VT), 1 };
1372    return Ret;
1373  }
1374
1375  SDNode(unsigned Opc, const DebugLoc dl, SDVTList VTs, const SDValue *Ops,
1376         unsigned NumOps)
1377    : NodeType(Opc), OperandsNeedDelete(true), HasDebugValue(false),
1378      SubclassData(0), NodeId(-1),
1379      OperandList(NumOps ? new SDUse[NumOps] : 0),
1380      ValueList(VTs.VTs), UseList(NULL),
1381      NumOperands(NumOps), NumValues(VTs.NumVTs),
1382      debugLoc(dl) {
1383    for (unsigned i = 0; i != NumOps; ++i) {
1384      OperandList[i].setUser(this);
1385      OperandList[i].setInitial(Ops[i]);
1386    }
1387    checkForCycles(this);
1388  }
1389
1390  /// This constructor adds no operands itself; operands can be
1391  /// set later with InitOperands.
1392  SDNode(unsigned Opc, const DebugLoc dl, SDVTList VTs)
1393    : NodeType(Opc), OperandsNeedDelete(false), HasDebugValue(false),
1394      SubclassData(0), NodeId(-1), OperandList(0), ValueList(VTs.VTs),
1395      UseList(NULL), NumOperands(0), NumValues(VTs.NumVTs),
1396      debugLoc(dl) {}
1397
1398  /// InitOperands - Initialize the operands list of this with 1 operand.
1399  void InitOperands(SDUse *Ops, const SDValue &Op0) {
1400    Ops[0].setUser(this);
1401    Ops[0].setInitial(Op0);
1402    NumOperands = 1;
1403    OperandList = Ops;
1404    checkForCycles(this);
1405  }
1406
1407  /// InitOperands - Initialize the operands list of this with 2 operands.
1408  void InitOperands(SDUse *Ops, const SDValue &Op0, const SDValue &Op1) {
1409    Ops[0].setUser(this);
1410    Ops[0].setInitial(Op0);
1411    Ops[1].setUser(this);
1412    Ops[1].setInitial(Op1);
1413    NumOperands = 2;
1414    OperandList = Ops;
1415    checkForCycles(this);
1416  }
1417
1418  /// InitOperands - Initialize the operands list of this with 3 operands.
1419  void InitOperands(SDUse *Ops, const SDValue &Op0, const SDValue &Op1,
1420                    const SDValue &Op2) {
1421    Ops[0].setUser(this);
1422    Ops[0].setInitial(Op0);
1423    Ops[1].setUser(this);
1424    Ops[1].setInitial(Op1);
1425    Ops[2].setUser(this);
1426    Ops[2].setInitial(Op2);
1427    NumOperands = 3;
1428    OperandList = Ops;
1429    checkForCycles(this);
1430  }
1431
1432  /// InitOperands - Initialize the operands list of this with 4 operands.
1433  void InitOperands(SDUse *Ops, const SDValue &Op0, const SDValue &Op1,
1434                    const SDValue &Op2, const SDValue &Op3) {
1435    Ops[0].setUser(this);
1436    Ops[0].setInitial(Op0);
1437    Ops[1].setUser(this);
1438    Ops[1].setInitial(Op1);
1439    Ops[2].setUser(this);
1440    Ops[2].setInitial(Op2);
1441    Ops[3].setUser(this);
1442    Ops[3].setInitial(Op3);
1443    NumOperands = 4;
1444    OperandList = Ops;
1445    checkForCycles(this);
1446  }
1447
1448  /// InitOperands - Initialize the operands list of this with N operands.
1449  void InitOperands(SDUse *Ops, const SDValue *Vals, unsigned N) {
1450    for (unsigned i = 0; i != N; ++i) {
1451      Ops[i].setUser(this);
1452      Ops[i].setInitial(Vals[i]);
1453    }
1454    NumOperands = N;
1455    OperandList = Ops;
1456    checkForCycles(this);
1457  }
1458
1459  /// DropOperands - Release the operands and set this node to have
1460  /// zero operands.
1461  void DropOperands();
1462};
1463
1464
1465// Define inline functions from the SDValue class.
1466
1467inline unsigned SDValue::getOpcode() const {
1468  return Node->getOpcode();
1469}
1470inline EVT SDValue::getValueType() const {
1471  return Node->getValueType(ResNo);
1472}
1473inline unsigned SDValue::getNumOperands() const {
1474  return Node->getNumOperands();
1475}
1476inline const SDValue &SDValue::getOperand(unsigned i) const {
1477  return Node->getOperand(i);
1478}
1479inline uint64_t SDValue::getConstantOperandVal(unsigned i) const {
1480  return Node->getConstantOperandVal(i);
1481}
1482inline bool SDValue::isTargetOpcode() const {
1483  return Node->isTargetOpcode();
1484}
1485inline bool SDValue::isTargetMemoryOpcode() const {
1486  return Node->isTargetMemoryOpcode();
1487}
1488inline bool SDValue::isMachineOpcode() const {
1489  return Node->isMachineOpcode();
1490}
1491inline unsigned SDValue::getMachineOpcode() const {
1492  return Node->getMachineOpcode();
1493}
1494inline bool SDValue::use_empty() const {
1495  return !Node->hasAnyUseOfValue(ResNo);
1496}
1497inline bool SDValue::hasOneUse() const {
1498  return Node->hasNUsesOfValue(1, ResNo);
1499}
1500inline const DebugLoc SDValue::getDebugLoc() const {
1501  return Node->getDebugLoc();
1502}
1503
1504// Define inline functions from the SDUse class.
1505
1506inline void SDUse::set(const SDValue &V) {
1507  if (Val.getNode()) removeFromList();
1508  Val = V;
1509  if (V.getNode()) V.getNode()->addUse(*this);
1510}
1511
1512inline void SDUse::setInitial(const SDValue &V) {
1513  Val = V;
1514  V.getNode()->addUse(*this);
1515}
1516
1517inline void SDUse::setNode(SDNode *N) {
1518  if (Val.getNode()) removeFromList();
1519  Val.setNode(N);
1520  if (N) N->addUse(*this);
1521}
1522
1523/// UnarySDNode - This class is used for single-operand SDNodes.  This is solely
1524/// to allow co-allocation of node operands with the node itself.
1525class UnarySDNode : public SDNode {
1526  SDUse Op;
1527public:
1528  UnarySDNode(unsigned Opc, DebugLoc dl, SDVTList VTs, SDValue X)
1529    : SDNode(Opc, dl, VTs) {
1530    InitOperands(&Op, X);
1531  }
1532};
1533
1534/// BinarySDNode - This class is used for two-operand SDNodes.  This is solely
1535/// to allow co-allocation of node operands with the node itself.
1536class BinarySDNode : public SDNode {
1537  SDUse Ops[2];
1538public:
1539  BinarySDNode(unsigned Opc, DebugLoc dl, SDVTList VTs, SDValue X, SDValue Y)
1540    : SDNode(Opc, dl, VTs) {
1541    InitOperands(Ops, X, Y);
1542  }
1543};
1544
1545/// TernarySDNode - This class is used for three-operand SDNodes. This is solely
1546/// to allow co-allocation of node operands with the node itself.
1547class TernarySDNode : public SDNode {
1548  SDUse Ops[3];
1549public:
1550  TernarySDNode(unsigned Opc, DebugLoc dl, SDVTList VTs, SDValue X, SDValue Y,
1551                SDValue Z)
1552    : SDNode(Opc, dl, VTs) {
1553    InitOperands(Ops, X, Y, Z);
1554  }
1555};
1556
1557
1558/// HandleSDNode - This class is used to form a handle around another node that
1559/// is persistant and is updated across invocations of replaceAllUsesWith on its
1560/// operand.  This node should be directly created by end-users and not added to
1561/// the AllNodes list.
1562class HandleSDNode : public SDNode {
1563  SDUse Op;
1564public:
1565  // FIXME: Remove the "noinline" attribute once <rdar://problem/5852746> is
1566  // fixed.
1567#ifdef __GNUC__
1568  explicit __attribute__((__noinline__)) HandleSDNode(SDValue X)
1569#else
1570  explicit HandleSDNode(SDValue X)
1571#endif
1572    : SDNode(ISD::HANDLENODE, DebugLoc::getUnknownLoc(),
1573             getSDVTList(MVT::Other)) {
1574    InitOperands(&Op, X);
1575  }
1576  ~HandleSDNode();
1577  const SDValue &getValue() const { return Op; }
1578};
1579
1580/// Abstact virtual class for operations for memory operations
1581class MemSDNode : public SDNode {
1582private:
1583  // MemoryVT - VT of in-memory value.
1584  EVT MemoryVT;
1585
1586protected:
1587  /// MMO - Memory reference information.
1588  MachineMemOperand *MMO;
1589
1590public:
1591  MemSDNode(unsigned Opc, DebugLoc dl, SDVTList VTs, EVT MemoryVT,
1592            MachineMemOperand *MMO);
1593
1594  MemSDNode(unsigned Opc, DebugLoc dl, SDVTList VTs, const SDValue *Ops,
1595            unsigned NumOps, EVT MemoryVT, MachineMemOperand *MMO);
1596
1597  bool readMem() const { return MMO->isLoad(); }
1598  bool writeMem() const { return MMO->isStore(); }
1599
1600  /// Returns alignment and volatility of the memory access
1601  unsigned getOriginalAlignment() const {
1602    return MMO->getBaseAlignment();
1603  }
1604  unsigned getAlignment() const {
1605    return MMO->getAlignment();
1606  }
1607
1608  /// getRawSubclassData - Return the SubclassData value, which contains an
1609  /// encoding of the volatile flag, as well as bits used by subclasses. This
1610  /// function should only be used to compute a FoldingSetNodeID value.
1611  unsigned getRawSubclassData() const {
1612    return SubclassData;
1613  }
1614
1615  // We access subclass data here so that we can check consistency
1616  // with MachineMemOperand information.
1617  bool isVolatile() const { return (SubclassData >> 5) & 1; }
1618  bool isNonTemporal() const { return (SubclassData >> 6) & 1; }
1619
1620  /// Returns the SrcValue and offset that describes the location of the access
1621  const Value *getSrcValue() const { return MMO->getValue(); }
1622  int64_t getSrcValueOffset() const { return MMO->getOffset(); }
1623
1624  /// getMemoryVT - Return the type of the in-memory value.
1625  EVT getMemoryVT() const { return MemoryVT; }
1626
1627  /// getMemOperand - Return a MachineMemOperand object describing the memory
1628  /// reference performed by operation.
1629  MachineMemOperand *getMemOperand() const { return MMO; }
1630
1631  /// refineAlignment - Update this MemSDNode's MachineMemOperand information
1632  /// to reflect the alignment of NewMMO, if it has a greater alignment.
1633  /// This must only be used when the new alignment applies to all users of
1634  /// this MachineMemOperand.
1635  void refineAlignment(const MachineMemOperand *NewMMO) {
1636    MMO->refineAlignment(NewMMO);
1637  }
1638
1639  const SDValue &getChain() const { return getOperand(0); }
1640  const SDValue &getBasePtr() const {
1641    return getOperand(getOpcode() == ISD::STORE ? 2 : 1);
1642  }
1643
1644  // Methods to support isa and dyn_cast
1645  static bool classof(const MemSDNode *) { return true; }
1646  static bool classof(const SDNode *N) {
1647    // For some targets, we lower some target intrinsics to a MemIntrinsicNode
1648    // with either an intrinsic or a target opcode.
1649    return N->getOpcode() == ISD::LOAD                ||
1650           N->getOpcode() == ISD::STORE               ||
1651           N->getOpcode() == ISD::ATOMIC_CMP_SWAP     ||
1652           N->getOpcode() == ISD::ATOMIC_SWAP         ||
1653           N->getOpcode() == ISD::ATOMIC_LOAD_ADD     ||
1654           N->getOpcode() == ISD::ATOMIC_LOAD_SUB     ||
1655           N->getOpcode() == ISD::ATOMIC_LOAD_AND     ||
1656           N->getOpcode() == ISD::ATOMIC_LOAD_OR      ||
1657           N->getOpcode() == ISD::ATOMIC_LOAD_XOR     ||
1658           N->getOpcode() == ISD::ATOMIC_LOAD_NAND    ||
1659           N->getOpcode() == ISD::ATOMIC_LOAD_MIN     ||
1660           N->getOpcode() == ISD::ATOMIC_LOAD_MAX     ||
1661           N->getOpcode() == ISD::ATOMIC_LOAD_UMIN    ||
1662           N->getOpcode() == ISD::ATOMIC_LOAD_UMAX    ||
1663           N->isTargetMemoryOpcode();
1664  }
1665};
1666
1667/// AtomicSDNode - A SDNode reprenting atomic operations.
1668///
1669class AtomicSDNode : public MemSDNode {
1670  SDUse Ops[4];
1671
1672public:
1673  // Opc:   opcode for atomic
1674  // VTL:    value type list
1675  // Chain:  memory chain for operaand
1676  // Ptr:    address to update as a SDValue
1677  // Cmp:    compare value
1678  // Swp:    swap value
1679  // SrcVal: address to update as a Value (used for MemOperand)
1680  // Align:  alignment of memory
1681  AtomicSDNode(unsigned Opc, DebugLoc dl, SDVTList VTL, EVT MemVT,
1682               SDValue Chain, SDValue Ptr,
1683               SDValue Cmp, SDValue Swp, MachineMemOperand *MMO)
1684    : MemSDNode(Opc, dl, VTL, MemVT, MMO) {
1685    assert(readMem() && "Atomic MachineMemOperand is not a load!");
1686    assert(writeMem() && "Atomic MachineMemOperand is not a store!");
1687    InitOperands(Ops, Chain, Ptr, Cmp, Swp);
1688  }
1689  AtomicSDNode(unsigned Opc, DebugLoc dl, SDVTList VTL, EVT MemVT,
1690               SDValue Chain, SDValue Ptr,
1691               SDValue Val, MachineMemOperand *MMO)
1692    : MemSDNode(Opc, dl, VTL, MemVT, MMO) {
1693    assert(readMem() && "Atomic MachineMemOperand is not a load!");
1694    assert(writeMem() && "Atomic MachineMemOperand is not a store!");
1695    InitOperands(Ops, Chain, Ptr, Val);
1696  }
1697
1698  const SDValue &getBasePtr() const { return getOperand(1); }
1699  const SDValue &getVal() const { return getOperand(2); }
1700
1701  bool isCompareAndSwap() const {
1702    unsigned Op = getOpcode();
1703    return Op == ISD::ATOMIC_CMP_SWAP;
1704  }
1705
1706  // Methods to support isa and dyn_cast
1707  static bool classof(const AtomicSDNode *) { return true; }
1708  static bool classof(const SDNode *N) {
1709    return N->getOpcode() == ISD::ATOMIC_CMP_SWAP     ||
1710           N->getOpcode() == ISD::ATOMIC_SWAP         ||
1711           N->getOpcode() == ISD::ATOMIC_LOAD_ADD     ||
1712           N->getOpcode() == ISD::ATOMIC_LOAD_SUB     ||
1713           N->getOpcode() == ISD::ATOMIC_LOAD_AND     ||
1714           N->getOpcode() == ISD::ATOMIC_LOAD_OR      ||
1715           N->getOpcode() == ISD::ATOMIC_LOAD_XOR     ||
1716           N->getOpcode() == ISD::ATOMIC_LOAD_NAND    ||
1717           N->getOpcode() == ISD::ATOMIC_LOAD_MIN     ||
1718           N->getOpcode() == ISD::ATOMIC_LOAD_MAX     ||
1719           N->getOpcode() == ISD::ATOMIC_LOAD_UMIN    ||
1720           N->getOpcode() == ISD::ATOMIC_LOAD_UMAX;
1721  }
1722};
1723
1724/// MemIntrinsicSDNode - This SDNode is used for target intrinsics that touch
1725/// memory and need an associated MachineMemOperand. Its opcode may be
1726/// INTRINSIC_VOID, INTRINSIC_W_CHAIN, or a target-specific opcode with a
1727/// value not less than FIRST_TARGET_MEMORY_OPCODE.
1728class MemIntrinsicSDNode : public MemSDNode {
1729public:
1730  MemIntrinsicSDNode(unsigned Opc, DebugLoc dl, SDVTList VTs,
1731                     const SDValue *Ops, unsigned NumOps,
1732                     EVT MemoryVT, MachineMemOperand *MMO)
1733    : MemSDNode(Opc, dl, VTs, Ops, NumOps, MemoryVT, MMO) {
1734  }
1735
1736  // Methods to support isa and dyn_cast
1737  static bool classof(const MemIntrinsicSDNode *) { return true; }
1738  static bool classof(const SDNode *N) {
1739    // We lower some target intrinsics to their target opcode
1740    // early a node with a target opcode can be of this class
1741    return N->getOpcode() == ISD::INTRINSIC_W_CHAIN ||
1742           N->getOpcode() == ISD::INTRINSIC_VOID ||
1743           N->isTargetMemoryOpcode();
1744  }
1745};
1746
1747/// ShuffleVectorSDNode - This SDNode is used to implement the code generator
1748/// support for the llvm IR shufflevector instruction.  It combines elements
1749/// from two input vectors into a new input vector, with the selection and
1750/// ordering of elements determined by an array of integers, referred to as
1751/// the shuffle mask.  For input vectors of width N, mask indices of 0..N-1
1752/// refer to elements from the LHS input, and indices from N to 2N-1 the RHS.
1753/// An index of -1 is treated as undef, such that the code generator may put
1754/// any value in the corresponding element of the result.
1755class ShuffleVectorSDNode : public SDNode {
1756  SDUse Ops[2];
1757
1758  // The memory for Mask is owned by the SelectionDAG's OperandAllocator, and
1759  // is freed when the SelectionDAG object is destroyed.
1760  const int *Mask;
1761protected:
1762  friend class SelectionDAG;
1763  ShuffleVectorSDNode(EVT VT, DebugLoc dl, SDValue N1, SDValue N2,
1764                      const int *M)
1765    : SDNode(ISD::VECTOR_SHUFFLE, dl, getSDVTList(VT)), Mask(M) {
1766    InitOperands(Ops, N1, N2);
1767  }
1768public:
1769
1770  void getMask(SmallVectorImpl<int> &M) const {
1771    EVT VT = getValueType(0);
1772    M.clear();
1773    for (unsigned i = 0, e = VT.getVectorNumElements(); i != e; ++i)
1774      M.push_back(Mask[i]);
1775  }
1776  int getMaskElt(unsigned Idx) const {
1777    assert(Idx < getValueType(0).getVectorNumElements() && "Idx out of range!");
1778    return Mask[Idx];
1779  }
1780
1781  bool isSplat() const { return isSplatMask(Mask, getValueType(0)); }
1782  int  getSplatIndex() const {
1783    assert(isSplat() && "Cannot get splat index for non-splat!");
1784    EVT VT = getValueType(0);
1785    for (unsigned i = 0, e = VT.getVectorNumElements(); i != e; ++i) {
1786      if (Mask[i] != -1)
1787        return Mask[i];
1788    }
1789    return -1;
1790  }
1791  static bool isSplatMask(const int *Mask, EVT VT);
1792
1793  static bool classof(const ShuffleVectorSDNode *) { return true; }
1794  static bool classof(const SDNode *N) {
1795    return N->getOpcode() == ISD::VECTOR_SHUFFLE;
1796  }
1797};
1798
1799class ConstantSDNode : public SDNode {
1800  const ConstantInt *Value;
1801  friend class SelectionDAG;
1802  ConstantSDNode(bool isTarget, const ConstantInt *val, EVT VT)
1803    : SDNode(isTarget ? ISD::TargetConstant : ISD::Constant,
1804             DebugLoc::getUnknownLoc(), getSDVTList(VT)), Value(val) {
1805  }
1806public:
1807
1808  const ConstantInt *getConstantIntValue() const { return Value; }
1809  const APInt &getAPIntValue() const { return Value->getValue(); }
1810  uint64_t getZExtValue() const { return Value->getZExtValue(); }
1811  int64_t getSExtValue() const { return Value->getSExtValue(); }
1812
1813  bool isNullValue() const { return Value->isNullValue(); }
1814  bool isAllOnesValue() const { return Value->isAllOnesValue(); }
1815
1816  static bool classof(const ConstantSDNode *) { return true; }
1817  static bool classof(const SDNode *N) {
1818    return N->getOpcode() == ISD::Constant ||
1819           N->getOpcode() == ISD::TargetConstant;
1820  }
1821};
1822
1823class ConstantFPSDNode : public SDNode {
1824  const ConstantFP *Value;
1825  friend class SelectionDAG;
1826  ConstantFPSDNode(bool isTarget, const ConstantFP *val, EVT VT)
1827    : SDNode(isTarget ? ISD::TargetConstantFP : ISD::ConstantFP,
1828             DebugLoc::getUnknownLoc(), getSDVTList(VT)), Value(val) {
1829  }
1830public:
1831
1832  const APFloat& getValueAPF() const { return Value->getValueAPF(); }
1833  const ConstantFP *getConstantFPValue() const { return Value; }
1834
1835  /// isZero - Return true if the value is positive or negative zero.
1836  bool isZero() const { return Value->isZero(); }
1837
1838  /// isNaN - Return true if the value is a NaN.
1839  bool isNaN() const { return Value->isNaN(); }
1840
1841  /// isExactlyValue - We don't rely on operator== working on double values, as
1842  /// it returns true for things that are clearly not equal, like -0.0 and 0.0.
1843  /// As such, this method can be used to do an exact bit-for-bit comparison of
1844  /// two floating point values.
1845
1846  /// We leave the version with the double argument here because it's just so
1847  /// convenient to write "2.0" and the like.  Without this function we'd
1848  /// have to duplicate its logic everywhere it's called.
1849  bool isExactlyValue(double V) const {
1850    bool ignored;
1851    // convert is not supported on this type
1852    if (&Value->getValueAPF().getSemantics() == &APFloat::PPCDoubleDouble)
1853      return false;
1854    APFloat Tmp(V);
1855    Tmp.convert(Value->getValueAPF().getSemantics(),
1856                APFloat::rmNearestTiesToEven, &ignored);
1857    return isExactlyValue(Tmp);
1858  }
1859  bool isExactlyValue(const APFloat& V) const;
1860
1861  bool isValueValidForType(EVT VT, const APFloat& Val);
1862
1863  static bool classof(const ConstantFPSDNode *) { return true; }
1864  static bool classof(const SDNode *N) {
1865    return N->getOpcode() == ISD::ConstantFP ||
1866           N->getOpcode() == ISD::TargetConstantFP;
1867  }
1868};
1869
1870class GlobalAddressSDNode : public SDNode {
1871  GlobalValue *TheGlobal;
1872  int64_t Offset;
1873  unsigned char TargetFlags;
1874  friend class SelectionDAG;
1875  GlobalAddressSDNode(unsigned Opc, const GlobalValue *GA, EVT VT,
1876                      int64_t o, unsigned char TargetFlags);
1877public:
1878
1879  GlobalValue *getGlobal() const { return TheGlobal; }
1880  int64_t getOffset() const { return Offset; }
1881  unsigned char getTargetFlags() const { return TargetFlags; }
1882  // Return the address space this GlobalAddress belongs to.
1883  unsigned getAddressSpace() const;
1884
1885  static bool classof(const GlobalAddressSDNode *) { return true; }
1886  static bool classof(const SDNode *N) {
1887    return N->getOpcode() == ISD::GlobalAddress ||
1888           N->getOpcode() == ISD::TargetGlobalAddress ||
1889           N->getOpcode() == ISD::GlobalTLSAddress ||
1890           N->getOpcode() == ISD::TargetGlobalTLSAddress;
1891  }
1892};
1893
1894class FrameIndexSDNode : public SDNode {
1895  int FI;
1896  friend class SelectionDAG;
1897  FrameIndexSDNode(int fi, EVT VT, bool isTarg)
1898    : SDNode(isTarg ? ISD::TargetFrameIndex : ISD::FrameIndex,
1899      DebugLoc::getUnknownLoc(), getSDVTList(VT)), FI(fi) {
1900  }
1901public:
1902
1903  int getIndex() const { return FI; }
1904
1905  static bool classof(const FrameIndexSDNode *) { return true; }
1906  static bool classof(const SDNode *N) {
1907    return N->getOpcode() == ISD::FrameIndex ||
1908           N->getOpcode() == ISD::TargetFrameIndex;
1909  }
1910};
1911
1912class JumpTableSDNode : public SDNode {
1913  int JTI;
1914  unsigned char TargetFlags;
1915  friend class SelectionDAG;
1916  JumpTableSDNode(int jti, EVT VT, bool isTarg, unsigned char TF)
1917    : SDNode(isTarg ? ISD::TargetJumpTable : ISD::JumpTable,
1918      DebugLoc::getUnknownLoc(), getSDVTList(VT)), JTI(jti), TargetFlags(TF) {
1919  }
1920public:
1921
1922  int getIndex() const { return JTI; }
1923  unsigned char getTargetFlags() const { return TargetFlags; }
1924
1925  static bool classof(const JumpTableSDNode *) { return true; }
1926  static bool classof(const SDNode *N) {
1927    return N->getOpcode() == ISD::JumpTable ||
1928           N->getOpcode() == ISD::TargetJumpTable;
1929  }
1930};
1931
1932class ConstantPoolSDNode : public SDNode {
1933  union {
1934    Constant *ConstVal;
1935    MachineConstantPoolValue *MachineCPVal;
1936  } Val;
1937  int Offset;  // It's a MachineConstantPoolValue if top bit is set.
1938  unsigned Alignment;  // Minimum alignment requirement of CP (not log2 value).
1939  unsigned char TargetFlags;
1940  friend class SelectionDAG;
1941  ConstantPoolSDNode(bool isTarget, Constant *c, EVT VT, int o, unsigned Align,
1942                     unsigned char TF)
1943    : SDNode(isTarget ? ISD::TargetConstantPool : ISD::ConstantPool,
1944             DebugLoc::getUnknownLoc(),
1945             getSDVTList(VT)), Offset(o), Alignment(Align), TargetFlags(TF) {
1946    assert((int)Offset >= 0 && "Offset is too large");
1947    Val.ConstVal = c;
1948  }
1949  ConstantPoolSDNode(bool isTarget, MachineConstantPoolValue *v,
1950                     EVT VT, int o, unsigned Align, unsigned char TF)
1951    : SDNode(isTarget ? ISD::TargetConstantPool : ISD::ConstantPool,
1952             DebugLoc::getUnknownLoc(),
1953             getSDVTList(VT)), Offset(o), Alignment(Align), TargetFlags(TF) {
1954    assert((int)Offset >= 0 && "Offset is too large");
1955    Val.MachineCPVal = v;
1956    Offset |= 1 << (sizeof(unsigned)*CHAR_BIT-1);
1957  }
1958public:
1959
1960
1961  bool isMachineConstantPoolEntry() const {
1962    return (int)Offset < 0;
1963  }
1964
1965  Constant *getConstVal() const {
1966    assert(!isMachineConstantPoolEntry() && "Wrong constantpool type");
1967    return Val.ConstVal;
1968  }
1969
1970  MachineConstantPoolValue *getMachineCPVal() const {
1971    assert(isMachineConstantPoolEntry() && "Wrong constantpool type");
1972    return Val.MachineCPVal;
1973  }
1974
1975  int getOffset() const {
1976    return Offset & ~(1 << (sizeof(unsigned)*CHAR_BIT-1));
1977  }
1978
1979  // Return the alignment of this constant pool object, which is either 0 (for
1980  // default alignment) or the desired value.
1981  unsigned getAlignment() const { return Alignment; }
1982  unsigned char getTargetFlags() const { return TargetFlags; }
1983
1984  const Type *getType() const;
1985
1986  static bool classof(const ConstantPoolSDNode *) { return true; }
1987  static bool classof(const SDNode *N) {
1988    return N->getOpcode() == ISD::ConstantPool ||
1989           N->getOpcode() == ISD::TargetConstantPool;
1990  }
1991};
1992
1993class BasicBlockSDNode : public SDNode {
1994  MachineBasicBlock *MBB;
1995  friend class SelectionDAG;
1996  /// Debug info is meaningful and potentially useful here, but we create
1997  /// blocks out of order when they're jumped to, which makes it a bit
1998  /// harder.  Let's see if we need it first.
1999  explicit BasicBlockSDNode(MachineBasicBlock *mbb)
2000    : SDNode(ISD::BasicBlock, DebugLoc::getUnknownLoc(),
2001             getSDVTList(MVT::Other)), MBB(mbb) {
2002  }
2003public:
2004
2005  MachineBasicBlock *getBasicBlock() const { return MBB; }
2006
2007  static bool classof(const BasicBlockSDNode *) { return true; }
2008  static bool classof(const SDNode *N) {
2009    return N->getOpcode() == ISD::BasicBlock;
2010  }
2011};
2012
2013/// BuildVectorSDNode - A "pseudo-class" with methods for operating on
2014/// BUILD_VECTORs.
2015class BuildVectorSDNode : public SDNode {
2016  // These are constructed as SDNodes and then cast to BuildVectorSDNodes.
2017  explicit BuildVectorSDNode();        // Do not implement
2018public:
2019  /// isConstantSplat - Check if this is a constant splat, and if so, find the
2020  /// smallest element size that splats the vector.  If MinSplatBits is
2021  /// nonzero, the element size must be at least that large.  Note that the
2022  /// splat element may be the entire vector (i.e., a one element vector).
2023  /// Returns the splat element value in SplatValue.  Any undefined bits in
2024  /// that value are zero, and the corresponding bits in the SplatUndef mask
2025  /// are set.  The SplatBitSize value is set to the splat element size in
2026  /// bits.  HasAnyUndefs is set to true if any bits in the vector are
2027  /// undefined.  isBigEndian describes the endianness of the target.
2028  bool isConstantSplat(APInt &SplatValue, APInt &SplatUndef,
2029                       unsigned &SplatBitSize, bool &HasAnyUndefs,
2030                       unsigned MinSplatBits = 0, bool isBigEndian = false);
2031
2032  static inline bool classof(const BuildVectorSDNode *) { return true; }
2033  static inline bool classof(const SDNode *N) {
2034    return N->getOpcode() == ISD::BUILD_VECTOR;
2035  }
2036};
2037
2038/// SrcValueSDNode - An SDNode that holds an arbitrary LLVM IR Value. This is
2039/// used when the SelectionDAG needs to make a simple reference to something
2040/// in the LLVM IR representation.
2041///
2042class SrcValueSDNode : public SDNode {
2043  const Value *V;
2044  friend class SelectionDAG;
2045  /// Create a SrcValue for a general value.
2046  explicit SrcValueSDNode(const Value *v)
2047    : SDNode(ISD::SRCVALUE, DebugLoc::getUnknownLoc(),
2048             getSDVTList(MVT::Other)), V(v) {}
2049
2050public:
2051  /// getValue - return the contained Value.
2052  const Value *getValue() const { return V; }
2053
2054  static bool classof(const SrcValueSDNode *) { return true; }
2055  static bool classof(const SDNode *N) {
2056    return N->getOpcode() == ISD::SRCVALUE;
2057  }
2058};
2059
2060
2061class RegisterSDNode : public SDNode {
2062  unsigned Reg;
2063  friend class SelectionDAG;
2064  RegisterSDNode(unsigned reg, EVT VT)
2065    : SDNode(ISD::Register, DebugLoc::getUnknownLoc(),
2066             getSDVTList(VT)), Reg(reg) {
2067  }
2068public:
2069
2070  unsigned getReg() const { return Reg; }
2071
2072  static bool classof(const RegisterSDNode *) { return true; }
2073  static bool classof(const SDNode *N) {
2074    return N->getOpcode() == ISD::Register;
2075  }
2076};
2077
2078class BlockAddressSDNode : public SDNode {
2079  BlockAddress *BA;
2080  unsigned char TargetFlags;
2081  friend class SelectionDAG;
2082  BlockAddressSDNode(unsigned NodeTy, EVT VT, BlockAddress *ba,
2083                     unsigned char Flags)
2084    : SDNode(NodeTy, DebugLoc::getUnknownLoc(), getSDVTList(VT)),
2085             BA(ba), TargetFlags(Flags) {
2086  }
2087public:
2088  BlockAddress *getBlockAddress() const { return BA; }
2089  unsigned char getTargetFlags() const { return TargetFlags; }
2090
2091  static bool classof(const BlockAddressSDNode *) { return true; }
2092  static bool classof(const SDNode *N) {
2093    return N->getOpcode() == ISD::BlockAddress ||
2094           N->getOpcode() == ISD::TargetBlockAddress;
2095  }
2096};
2097
2098class EHLabelSDNode : public SDNode {
2099  SDUse Chain;
2100  MCSymbol *Label;
2101  friend class SelectionDAG;
2102  EHLabelSDNode(DebugLoc dl, SDValue ch, MCSymbol *L)
2103    : SDNode(ISD::EH_LABEL, dl, getSDVTList(MVT::Other)), Label(L) {
2104    InitOperands(&Chain, ch);
2105  }
2106public:
2107  MCSymbol *getLabel() const { return Label; }
2108
2109  static bool classof(const EHLabelSDNode *) { return true; }
2110  static bool classof(const SDNode *N) {
2111    return N->getOpcode() == ISD::EH_LABEL;
2112  }
2113};
2114
2115class ExternalSymbolSDNode : public SDNode {
2116  const char *Symbol;
2117  unsigned char TargetFlags;
2118
2119  friend class SelectionDAG;
2120  ExternalSymbolSDNode(bool isTarget, const char *Sym, unsigned char TF, EVT VT)
2121    : SDNode(isTarget ? ISD::TargetExternalSymbol : ISD::ExternalSymbol,
2122             DebugLoc::getUnknownLoc(),
2123             getSDVTList(VT)), Symbol(Sym), TargetFlags(TF) {
2124  }
2125public:
2126
2127  const char *getSymbol() const { return Symbol; }
2128  unsigned char getTargetFlags() const { return TargetFlags; }
2129
2130  static bool classof(const ExternalSymbolSDNode *) { return true; }
2131  static bool classof(const SDNode *N) {
2132    return N->getOpcode() == ISD::ExternalSymbol ||
2133           N->getOpcode() == ISD::TargetExternalSymbol;
2134  }
2135};
2136
2137class CondCodeSDNode : public SDNode {
2138  ISD::CondCode Condition;
2139  friend class SelectionDAG;
2140  explicit CondCodeSDNode(ISD::CondCode Cond)
2141    : SDNode(ISD::CONDCODE, DebugLoc::getUnknownLoc(),
2142             getSDVTList(MVT::Other)), Condition(Cond) {
2143  }
2144public:
2145
2146  ISD::CondCode get() const { return Condition; }
2147
2148  static bool classof(const CondCodeSDNode *) { return true; }
2149  static bool classof(const SDNode *N) {
2150    return N->getOpcode() == ISD::CONDCODE;
2151  }
2152};
2153
2154/// CvtRndSatSDNode - NOTE: avoid using this node as this may disappear in the
2155/// future and most targets don't support it.
2156class CvtRndSatSDNode : public SDNode {
2157  ISD::CvtCode CvtCode;
2158  friend class SelectionDAG;
2159  explicit CvtRndSatSDNode(EVT VT, DebugLoc dl, const SDValue *Ops,
2160                           unsigned NumOps, ISD::CvtCode Code)
2161    : SDNode(ISD::CONVERT_RNDSAT, dl, getSDVTList(VT), Ops, NumOps),
2162      CvtCode(Code) {
2163    assert(NumOps == 5 && "wrong number of operations");
2164  }
2165public:
2166  ISD::CvtCode getCvtCode() const { return CvtCode; }
2167
2168  static bool classof(const CvtRndSatSDNode *) { return true; }
2169  static bool classof(const SDNode *N) {
2170    return N->getOpcode() == ISD::CONVERT_RNDSAT;
2171  }
2172};
2173
2174namespace ISD {
2175  struct ArgFlagsTy {
2176  private:
2177    static const uint64_t NoFlagSet      = 0ULL;
2178    static const uint64_t ZExt           = 1ULL<<0;  ///< Zero extended
2179    static const uint64_t ZExtOffs       = 0;
2180    static const uint64_t SExt           = 1ULL<<1;  ///< Sign extended
2181    static const uint64_t SExtOffs       = 1;
2182    static const uint64_t InReg          = 1ULL<<2;  ///< Passed in register
2183    static const uint64_t InRegOffs      = 2;
2184    static const uint64_t SRet           = 1ULL<<3;  ///< Hidden struct-ret ptr
2185    static const uint64_t SRetOffs       = 3;
2186    static const uint64_t ByVal          = 1ULL<<4;  ///< Struct passed by value
2187    static const uint64_t ByValOffs      = 4;
2188    static const uint64_t Nest           = 1ULL<<5;  ///< Nested fn static chain
2189    static const uint64_t NestOffs       = 5;
2190    static const uint64_t ByValAlign     = 0xFULL << 6; //< Struct alignment
2191    static const uint64_t ByValAlignOffs = 6;
2192    static const uint64_t Split          = 1ULL << 10;
2193    static const uint64_t SplitOffs      = 10;
2194    static const uint64_t OrigAlign      = 0x1FULL<<27;
2195    static const uint64_t OrigAlignOffs  = 27;
2196    static const uint64_t ByValSize      = 0xffffffffULL << 32; //< Struct size
2197    static const uint64_t ByValSizeOffs  = 32;
2198
2199    static const uint64_t One            = 1ULL; //< 1 of this type, for shifts
2200
2201    uint64_t Flags;
2202  public:
2203    ArgFlagsTy() : Flags(0) { }
2204
2205    bool isZExt()   const { return Flags & ZExt; }
2206    void setZExt()  { Flags |= One << ZExtOffs; }
2207
2208    bool isSExt()   const { return Flags & SExt; }
2209    void setSExt()  { Flags |= One << SExtOffs; }
2210
2211    bool isInReg()  const { return Flags & InReg; }
2212    void setInReg() { Flags |= One << InRegOffs; }
2213
2214    bool isSRet()   const { return Flags & SRet; }
2215    void setSRet()  { Flags |= One << SRetOffs; }
2216
2217    bool isByVal()  const { return Flags & ByVal; }
2218    void setByVal() { Flags |= One << ByValOffs; }
2219
2220    bool isNest()   const { return Flags & Nest; }
2221    void setNest()  { Flags |= One << NestOffs; }
2222
2223    unsigned getByValAlign() const {
2224      return (unsigned)
2225        ((One << ((Flags & ByValAlign) >> ByValAlignOffs)) / 2);
2226    }
2227    void setByValAlign(unsigned A) {
2228      Flags = (Flags & ~ByValAlign) |
2229        (uint64_t(Log2_32(A) + 1) << ByValAlignOffs);
2230    }
2231
2232    bool isSplit()   const { return Flags & Split; }
2233    void setSplit()  { Flags |= One << SplitOffs; }
2234
2235    unsigned getOrigAlign() const {
2236      return (unsigned)
2237        ((One << ((Flags & OrigAlign) >> OrigAlignOffs)) / 2);
2238    }
2239    void setOrigAlign(unsigned A) {
2240      Flags = (Flags & ~OrigAlign) |
2241        (uint64_t(Log2_32(A) + 1) << OrigAlignOffs);
2242    }
2243
2244    unsigned getByValSize() const {
2245      return (unsigned)((Flags & ByValSize) >> ByValSizeOffs);
2246    }
2247    void setByValSize(unsigned S) {
2248      Flags = (Flags & ~ByValSize) | (uint64_t(S) << ByValSizeOffs);
2249    }
2250
2251    /// getArgFlagsString - Returns the flags as a string, eg: "zext align:4".
2252    std::string getArgFlagsString();
2253
2254    /// getRawBits - Represent the flags as a bunch of bits.
2255    uint64_t getRawBits() const { return Flags; }
2256  };
2257
2258  /// InputArg - This struct carries flags and type information about a
2259  /// single incoming (formal) argument or incoming (from the perspective
2260  /// of the caller) return value virtual register.
2261  ///
2262  struct InputArg {
2263    ArgFlagsTy Flags;
2264    EVT VT;
2265    bool Used;
2266
2267    InputArg() : VT(MVT::Other), Used(false) {}
2268    InputArg(ISD::ArgFlagsTy flags, EVT vt, bool used)
2269      : Flags(flags), VT(vt), Used(used) {
2270      assert(VT.isSimple() &&
2271             "InputArg value type must be Simple!");
2272    }
2273  };
2274
2275  /// OutputArg - This struct carries flags and a value for a
2276  /// single outgoing (actual) argument or outgoing (from the perspective
2277  /// of the caller) return value virtual register.
2278  ///
2279  struct OutputArg {
2280    ArgFlagsTy Flags;
2281    SDValue Val;
2282    bool IsFixed;
2283
2284    OutputArg() : IsFixed(false) {}
2285    OutputArg(ISD::ArgFlagsTy flags, SDValue val, bool isfixed)
2286      : Flags(flags), Val(val), IsFixed(isfixed) {
2287      assert(Val.getValueType().isSimple() &&
2288             "OutputArg value type must be Simple!");
2289    }
2290  };
2291}
2292
2293/// VTSDNode - This class is used to represent EVT's, which are used
2294/// to parameterize some operations.
2295class VTSDNode : public SDNode {
2296  EVT ValueType;
2297  friend class SelectionDAG;
2298  explicit VTSDNode(EVT VT)
2299    : SDNode(ISD::VALUETYPE, DebugLoc::getUnknownLoc(),
2300             getSDVTList(MVT::Other)), ValueType(VT) {
2301  }
2302public:
2303
2304  EVT getVT() const { return ValueType; }
2305
2306  static bool classof(const VTSDNode *) { return true; }
2307  static bool classof(const SDNode *N) {
2308    return N->getOpcode() == ISD::VALUETYPE;
2309  }
2310};
2311
2312/// LSBaseSDNode - Base class for LoadSDNode and StoreSDNode
2313///
2314class LSBaseSDNode : public MemSDNode {
2315  //! Operand array for load and store
2316  /*!
2317    \note Moving this array to the base class captures more
2318    common functionality shared between LoadSDNode and
2319    StoreSDNode
2320   */
2321  SDUse Ops[4];
2322public:
2323  LSBaseSDNode(ISD::NodeType NodeTy, DebugLoc dl, SDValue *Operands,
2324               unsigned numOperands, SDVTList VTs, ISD::MemIndexedMode AM,
2325               EVT MemVT, MachineMemOperand *MMO)
2326    : MemSDNode(NodeTy, dl, VTs, MemVT, MMO) {
2327    SubclassData |= AM << 2;
2328    assert(getAddressingMode() == AM && "MemIndexedMode encoding error!");
2329    InitOperands(Ops, Operands, numOperands);
2330    assert((getOffset().getOpcode() == ISD::UNDEF || isIndexed()) &&
2331           "Only indexed loads and stores have a non-undef offset operand");
2332  }
2333
2334  const SDValue &getOffset() const {
2335    return getOperand(getOpcode() == ISD::LOAD ? 2 : 3);
2336  }
2337
2338  /// getAddressingMode - Return the addressing mode for this load or store:
2339  /// unindexed, pre-inc, pre-dec, post-inc, or post-dec.
2340  ISD::MemIndexedMode getAddressingMode() const {
2341    return ISD::MemIndexedMode((SubclassData >> 2) & 7);
2342  }
2343
2344  /// isIndexed - Return true if this is a pre/post inc/dec load/store.
2345  bool isIndexed() const { return getAddressingMode() != ISD::UNINDEXED; }
2346
2347  /// isUnindexed - Return true if this is NOT a pre/post inc/dec load/store.
2348  bool isUnindexed() const { return getAddressingMode() == ISD::UNINDEXED; }
2349
2350  static bool classof(const LSBaseSDNode *) { return true; }
2351  static bool classof(const SDNode *N) {
2352    return N->getOpcode() == ISD::LOAD ||
2353           N->getOpcode() == ISD::STORE;
2354  }
2355};
2356
2357/// LoadSDNode - This class is used to represent ISD::LOAD nodes.
2358///
2359class LoadSDNode : public LSBaseSDNode {
2360  friend class SelectionDAG;
2361  LoadSDNode(SDValue *ChainPtrOff, DebugLoc dl, SDVTList VTs,
2362             ISD::MemIndexedMode AM, ISD::LoadExtType ETy, EVT MemVT,
2363             MachineMemOperand *MMO)
2364    : LSBaseSDNode(ISD::LOAD, dl, ChainPtrOff, 3,
2365                   VTs, AM, MemVT, MMO) {
2366    SubclassData |= (unsigned short)ETy;
2367    assert(getExtensionType() == ETy && "LoadExtType encoding error!");
2368    assert(readMem() && "Load MachineMemOperand is not a load!");
2369    assert(!writeMem() && "Load MachineMemOperand is a store!");
2370  }
2371public:
2372
2373  /// getExtensionType - Return whether this is a plain node,
2374  /// or one of the varieties of value-extending loads.
2375  ISD::LoadExtType getExtensionType() const {
2376    return ISD::LoadExtType(SubclassData & 3);
2377  }
2378
2379  const SDValue &getBasePtr() const { return getOperand(1); }
2380  const SDValue &getOffset() const { return getOperand(2); }
2381
2382  static bool classof(const LoadSDNode *) { return true; }
2383  static bool classof(const SDNode *N) {
2384    return N->getOpcode() == ISD::LOAD;
2385  }
2386};
2387
2388/// StoreSDNode - This class is used to represent ISD::STORE nodes.
2389///
2390class StoreSDNode : public LSBaseSDNode {
2391  friend class SelectionDAG;
2392  StoreSDNode(SDValue *ChainValuePtrOff, DebugLoc dl, SDVTList VTs,
2393              ISD::MemIndexedMode AM, bool isTrunc, EVT MemVT,
2394              MachineMemOperand *MMO)
2395    : LSBaseSDNode(ISD::STORE, dl, ChainValuePtrOff, 4,
2396                   VTs, AM, MemVT, MMO) {
2397    SubclassData |= (unsigned short)isTrunc;
2398    assert(isTruncatingStore() == isTrunc && "isTrunc encoding error!");
2399    assert(!readMem() && "Store MachineMemOperand is a load!");
2400    assert(writeMem() && "Store MachineMemOperand is not a store!");
2401  }
2402public:
2403
2404  /// isTruncatingStore - Return true if the op does a truncation before store.
2405  /// For integers this is the same as doing a TRUNCATE and storing the result.
2406  /// For floats, it is the same as doing an FP_ROUND and storing the result.
2407  bool isTruncatingStore() const { return SubclassData & 1; }
2408
2409  const SDValue &getValue() const { return getOperand(1); }
2410  const SDValue &getBasePtr() const { return getOperand(2); }
2411  const SDValue &getOffset() const { return getOperand(3); }
2412
2413  static bool classof(const StoreSDNode *) { return true; }
2414  static bool classof(const SDNode *N) {
2415    return N->getOpcode() == ISD::STORE;
2416  }
2417};
2418
2419/// MachineSDNode - An SDNode that represents everything that will be needed
2420/// to construct a MachineInstr. These nodes are created during the
2421/// instruction selection proper phase.
2422///
2423class MachineSDNode : public SDNode {
2424public:
2425  typedef MachineMemOperand **mmo_iterator;
2426
2427private:
2428  friend class SelectionDAG;
2429  MachineSDNode(unsigned Opc, const DebugLoc DL, SDVTList VTs)
2430    : SDNode(Opc, DL, VTs), MemRefs(0), MemRefsEnd(0) {}
2431
2432  /// LocalOperands - Operands for this instruction, if they fit here. If
2433  /// they don't, this field is unused.
2434  SDUse LocalOperands[4];
2435
2436  /// MemRefs - Memory reference descriptions for this instruction.
2437  mmo_iterator MemRefs;
2438  mmo_iterator MemRefsEnd;
2439
2440public:
2441  mmo_iterator memoperands_begin() const { return MemRefs; }
2442  mmo_iterator memoperands_end() const { return MemRefsEnd; }
2443  bool memoperands_empty() const { return MemRefsEnd == MemRefs; }
2444
2445  /// setMemRefs - Assign this MachineSDNodes's memory reference descriptor
2446  /// list. This does not transfer ownership.
2447  void setMemRefs(mmo_iterator NewMemRefs, mmo_iterator NewMemRefsEnd) {
2448    MemRefs = NewMemRefs;
2449    MemRefsEnd = NewMemRefsEnd;
2450  }
2451
2452  static bool classof(const MachineSDNode *) { return true; }
2453  static bool classof(const SDNode *N) {
2454    return N->isMachineOpcode();
2455  }
2456};
2457
2458class SDNodeIterator : public std::iterator<std::forward_iterator_tag,
2459                                            SDNode, ptrdiff_t> {
2460  SDNode *Node;
2461  unsigned Operand;
2462
2463  SDNodeIterator(SDNode *N, unsigned Op) : Node(N), Operand(Op) {}
2464public:
2465  bool operator==(const SDNodeIterator& x) const {
2466    return Operand == x.Operand;
2467  }
2468  bool operator!=(const SDNodeIterator& x) const { return !operator==(x); }
2469
2470  const SDNodeIterator &operator=(const SDNodeIterator &I) {
2471    assert(I.Node == Node && "Cannot assign iterators to two different nodes!");
2472    Operand = I.Operand;
2473    return *this;
2474  }
2475
2476  pointer operator*() const {
2477    return Node->getOperand(Operand).getNode();
2478  }
2479  pointer operator->() const { return operator*(); }
2480
2481  SDNodeIterator& operator++() {                // Preincrement
2482    ++Operand;
2483    return *this;
2484  }
2485  SDNodeIterator operator++(int) { // Postincrement
2486    SDNodeIterator tmp = *this; ++*this; return tmp;
2487  }
2488  size_t operator-(SDNodeIterator Other) const {
2489    assert(Node == Other.Node &&
2490           "Cannot compare iterators of two different nodes!");
2491    return Operand - Other.Operand;
2492  }
2493
2494  static SDNodeIterator begin(SDNode *N) { return SDNodeIterator(N, 0); }
2495  static SDNodeIterator end  (SDNode *N) {
2496    return SDNodeIterator(N, N->getNumOperands());
2497  }
2498
2499  unsigned getOperand() const { return Operand; }
2500  const SDNode *getNode() const { return Node; }
2501};
2502
2503template <> struct GraphTraits<SDNode*> {
2504  typedef SDNode NodeType;
2505  typedef SDNodeIterator ChildIteratorType;
2506  static inline NodeType *getEntryNode(SDNode *N) { return N; }
2507  static inline ChildIteratorType child_begin(NodeType *N) {
2508    return SDNodeIterator::begin(N);
2509  }
2510  static inline ChildIteratorType child_end(NodeType *N) {
2511    return SDNodeIterator::end(N);
2512  }
2513};
2514
2515/// LargestSDNode - The largest SDNode class.
2516///
2517typedef LoadSDNode LargestSDNode;
2518
2519/// MostAlignedSDNode - The SDNode class with the greatest alignment
2520/// requirement.
2521///
2522typedef GlobalAddressSDNode MostAlignedSDNode;
2523
2524namespace ISD {
2525  /// isNormalLoad - Returns true if the specified node is a non-extending
2526  /// and unindexed load.
2527  inline bool isNormalLoad(const SDNode *N) {
2528    const LoadSDNode *Ld = dyn_cast<LoadSDNode>(N);
2529    return Ld && Ld->getExtensionType() == ISD::NON_EXTLOAD &&
2530      Ld->getAddressingMode() == ISD::UNINDEXED;
2531  }
2532
2533  /// isNON_EXTLoad - Returns true if the specified node is a non-extending
2534  /// load.
2535  inline bool isNON_EXTLoad(const SDNode *N) {
2536    return isa<LoadSDNode>(N) &&
2537      cast<LoadSDNode>(N)->getExtensionType() == ISD::NON_EXTLOAD;
2538  }
2539
2540  /// isEXTLoad - Returns true if the specified node is a EXTLOAD.
2541  ///
2542  inline bool isEXTLoad(const SDNode *N) {
2543    return isa<LoadSDNode>(N) &&
2544      cast<LoadSDNode>(N)->getExtensionType() == ISD::EXTLOAD;
2545  }
2546
2547  /// isSEXTLoad - Returns true if the specified node is a SEXTLOAD.
2548  ///
2549  inline bool isSEXTLoad(const SDNode *N) {
2550    return isa<LoadSDNode>(N) &&
2551      cast<LoadSDNode>(N)->getExtensionType() == ISD::SEXTLOAD;
2552  }
2553
2554  /// isZEXTLoad - Returns true if the specified node is a ZEXTLOAD.
2555  ///
2556  inline bool isZEXTLoad(const SDNode *N) {
2557    return isa<LoadSDNode>(N) &&
2558      cast<LoadSDNode>(N)->getExtensionType() == ISD::ZEXTLOAD;
2559  }
2560
2561  /// isUNINDEXEDLoad - Returns true if the specified node is an unindexed load.
2562  ///
2563  inline bool isUNINDEXEDLoad(const SDNode *N) {
2564    return isa<LoadSDNode>(N) &&
2565      cast<LoadSDNode>(N)->getAddressingMode() == ISD::UNINDEXED;
2566  }
2567
2568  /// isNormalStore - Returns true if the specified node is a non-truncating
2569  /// and unindexed store.
2570  inline bool isNormalStore(const SDNode *N) {
2571    const StoreSDNode *St = dyn_cast<StoreSDNode>(N);
2572    return St && !St->isTruncatingStore() &&
2573      St->getAddressingMode() == ISD::UNINDEXED;
2574  }
2575
2576  /// isNON_TRUNCStore - Returns true if the specified node is a non-truncating
2577  /// store.
2578  inline bool isNON_TRUNCStore(const SDNode *N) {
2579    return isa<StoreSDNode>(N) && !cast<StoreSDNode>(N)->isTruncatingStore();
2580  }
2581
2582  /// isTRUNCStore - Returns true if the specified node is a truncating
2583  /// store.
2584  inline bool isTRUNCStore(const SDNode *N) {
2585    return isa<StoreSDNode>(N) && cast<StoreSDNode>(N)->isTruncatingStore();
2586  }
2587
2588  /// isUNINDEXEDStore - Returns true if the specified node is an
2589  /// unindexed store.
2590  inline bool isUNINDEXEDStore(const SDNode *N) {
2591    return isa<StoreSDNode>(N) &&
2592      cast<StoreSDNode>(N)->getAddressingMode() == ISD::UNINDEXED;
2593  }
2594}
2595
2596
2597} // end llvm namespace
2598
2599#endif
2600