xref: /freebsd/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCISelLowering.h (revision cab6a39d7b343596a5823e65c0f7b426551ec22d)
1 //===-- PPCISelLowering.h - PPC32 DAG Lowering Interface --------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines the interfaces that PPC uses to lower LLVM code into a
10 // selection DAG.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_TARGET_POWERPC_PPCISELLOWERING_H
15 #define LLVM_LIB_TARGET_POWERPC_PPCISELLOWERING_H
16 
17 #include "PPCInstrInfo.h"
18 #include "llvm/CodeGen/CallingConvLower.h"
19 #include "llvm/CodeGen/MachineFunction.h"
20 #include "llvm/CodeGen/MachineMemOperand.h"
21 #include "llvm/CodeGen/SelectionDAG.h"
22 #include "llvm/CodeGen/SelectionDAGNodes.h"
23 #include "llvm/CodeGen/TargetLowering.h"
24 #include "llvm/CodeGen/ValueTypes.h"
25 #include "llvm/IR/Attributes.h"
26 #include "llvm/IR/CallingConv.h"
27 #include "llvm/IR/Function.h"
28 #include "llvm/IR/InlineAsm.h"
29 #include "llvm/IR/Metadata.h"
30 #include "llvm/IR/Type.h"
31 #include "llvm/Support/MachineValueType.h"
32 #include <utility>
33 
34 namespace llvm {
35 
36   namespace PPCISD {
37 
38     // When adding a NEW PPCISD node please add it to the correct position in
39     // the enum. The order of elements in this enum matters!
40     // Values that are added after this entry:
41     //     STBRX = ISD::FIRST_TARGET_MEMORY_OPCODE
42     // are considered memory opcodes and are treated differently than entries
43     // that come before it. For example, ADD or MUL should be placed before
44     // the ISD::FIRST_TARGET_MEMORY_OPCODE while a LOAD or STORE should come
45     // after it.
46   enum NodeType : unsigned {
47     // Start the numbering where the builtin ops and target ops leave off.
48     FIRST_NUMBER = ISD::BUILTIN_OP_END,
49 
50     /// FSEL - Traditional three-operand fsel node.
51     ///
52     FSEL,
53 
54     /// XSMAXCDP, XSMINCDP - C-type min/max instructions.
55     XSMAXCDP,
56     XSMINCDP,
57 
58     /// FCFID - The FCFID instruction, taking an f64 operand and producing
59     /// and f64 value containing the FP representation of the integer that
60     /// was temporarily in the f64 operand.
61     FCFID,
62 
63     /// Newer FCFID[US] integer-to-floating-point conversion instructions for
64     /// unsigned integers and single-precision outputs.
65     FCFIDU,
66     FCFIDS,
67     FCFIDUS,
68 
69     /// FCTI[D,W]Z - The FCTIDZ and FCTIWZ instructions, taking an f32 or f64
70     /// operand, producing an f64 value containing the integer representation
71     /// of that FP value.
72     FCTIDZ,
73     FCTIWZ,
74 
75     /// Newer FCTI[D,W]UZ floating-point-to-integer conversion instructions for
76     /// unsigned integers with round toward zero.
77     FCTIDUZ,
78     FCTIWUZ,
79 
80     /// Floating-point-to-interger conversion instructions
81     FP_TO_UINT_IN_VSR,
82     FP_TO_SINT_IN_VSR,
83 
84     /// VEXTS, ByteWidth - takes an input in VSFRC and produces an output in
85     /// VSFRC that is sign-extended from ByteWidth to a 64-byte integer.
86     VEXTS,
87 
88     /// Reciprocal estimate instructions (unary FP ops).
89     FRE,
90     FRSQRTE,
91 
92     /// Test instruction for software square root.
93     FTSQRT,
94 
95     /// Square root instruction.
96     FSQRT,
97 
98     /// VPERM - The PPC VPERM Instruction.
99     ///
100     VPERM,
101 
102     /// XXSPLT - The PPC VSX splat instructions
103     ///
104     XXSPLT,
105 
106     /// XXSPLTI_SP_TO_DP - The PPC VSX splat instructions for immediates for
107     /// converting immediate single precision numbers to double precision
108     /// vector or scalar.
109     XXSPLTI_SP_TO_DP,
110 
111     /// XXSPLTI32DX - The PPC XXSPLTI32DX instruction.
112     ///
113     XXSPLTI32DX,
114 
115     /// VECINSERT - The PPC vector insert instruction
116     ///
117     VECINSERT,
118 
119     /// VECSHL - The PPC vector shift left instruction
120     ///
121     VECSHL,
122 
123     /// XXPERMDI - The PPC XXPERMDI instruction
124     ///
125     XXPERMDI,
126 
127     /// The CMPB instruction (takes two operands of i32 or i64).
128     CMPB,
129 
130     /// Hi/Lo - These represent the high and low 16-bit parts of a global
131     /// address respectively.  These nodes have two operands, the first of
132     /// which must be a TargetGlobalAddress, and the second of which must be a
133     /// Constant.  Selected naively, these turn into 'lis G+C' and 'li G+C',
134     /// though these are usually folded into other nodes.
135     Hi,
136     Lo,
137 
138     /// The following two target-specific nodes are used for calls through
139     /// function pointers in the 64-bit SVR4 ABI.
140 
141     /// OPRC, CHAIN = DYNALLOC(CHAIN, NEGSIZE, FRAME_INDEX)
142     /// This instruction is lowered in PPCRegisterInfo::eliminateFrameIndex to
143     /// compute an allocation on the stack.
144     DYNALLOC,
145 
146     /// This instruction is lowered in PPCRegisterInfo::eliminateFrameIndex to
147     /// compute an offset from native SP to the address  of the most recent
148     /// dynamic alloca.
149     DYNAREAOFFSET,
150 
151     /// To avoid stack clash, allocation is performed by block and each block is
152     /// probed.
153     PROBED_ALLOCA,
154 
155     /// The result of the mflr at function entry, used for PIC code.
156     GlobalBaseReg,
157 
158     /// These nodes represent PPC shifts.
159     ///
160     /// For scalar types, only the last `n + 1` bits of the shift amounts
161     /// are used, where n is log2(sizeof(element) * 8). See sld/slw, etc.
162     /// for exact behaviors.
163     ///
164     /// For vector types, only the last n bits are used. See vsld.
165     SRL,
166     SRA,
167     SHL,
168 
169     /// FNMSUB - Negated multiply-subtract instruction.
170     FNMSUB,
171 
172     /// EXTSWSLI = The PPC extswsli instruction, which does an extend-sign
173     /// word and shift left immediate.
174     EXTSWSLI,
175 
176     /// The combination of sra[wd]i and addze used to implemented signed
177     /// integer division by a power of 2. The first operand is the dividend,
178     /// and the second is the constant shift amount (representing the
179     /// divisor).
180     SRA_ADDZE,
181 
182     /// CALL - A direct function call.
183     /// CALL_NOP is a call with the special NOP which follows 64-bit
184     /// CALL_NOTOC the caller does not use the TOC.
185     /// SVR4 calls and 32-bit/64-bit AIX calls.
186     CALL,
187     CALL_NOP,
188     CALL_NOTOC,
189 
190     /// CHAIN,FLAG = MTCTR(VAL, CHAIN[, INFLAG]) - Directly corresponds to a
191     /// MTCTR instruction.
192     MTCTR,
193 
194     /// CHAIN,FLAG = BCTRL(CHAIN, INFLAG) - Directly corresponds to a
195     /// BCTRL instruction.
196     BCTRL,
197 
198     /// CHAIN,FLAG = BCTRL(CHAIN, ADDR, INFLAG) - The combination of a bctrl
199     /// instruction and the TOC reload required on 64-bit ELF, 32-bit AIX
200     /// and 64-bit AIX.
201     BCTRL_LOAD_TOC,
202 
203     /// Return with a flag operand, matched by 'blr'
204     RET_FLAG,
205 
206     /// R32 = MFOCRF(CRREG, INFLAG) - Represents the MFOCRF instruction.
207     /// This copies the bits corresponding to the specified CRREG into the
208     /// resultant GPR.  Bits corresponding to other CR regs are undefined.
209     MFOCRF,
210 
211     /// Direct move from a VSX register to a GPR
212     MFVSR,
213 
214     /// Direct move from a GPR to a VSX register (algebraic)
215     MTVSRA,
216 
217     /// Direct move from a GPR to a VSX register (zero)
218     MTVSRZ,
219 
220     /// Direct move of 2 consecutive GPR to a VSX register.
221     BUILD_FP128,
222 
223     /// BUILD_SPE64 and EXTRACT_SPE are analogous to BUILD_PAIR and
224     /// EXTRACT_ELEMENT but take f64 arguments instead of i64, as i64 is
225     /// unsupported for this target.
226     /// Merge 2 GPRs to a single SPE register.
227     BUILD_SPE64,
228 
229     /// Extract SPE register component, second argument is high or low.
230     EXTRACT_SPE,
231 
232     /// Extract a subvector from signed integer vector and convert to FP.
233     /// It is primarily used to convert a (widened) illegal integer vector
234     /// type to a legal floating point vector type.
235     /// For example v2i32 -> widened to v4i32 -> v2f64
236     SINT_VEC_TO_FP,
237 
238     /// Extract a subvector from unsigned integer vector and convert to FP.
239     /// As with SINT_VEC_TO_FP, used for converting illegal types.
240     UINT_VEC_TO_FP,
241 
242     /// PowerPC instructions that have SCALAR_TO_VECTOR semantics tend to
243     /// place the value into the least significant element of the most
244     /// significant doubleword in the vector. This is not element zero for
245     /// anything smaller than a doubleword on either endianness. This node has
246     /// the same semantics as SCALAR_TO_VECTOR except that the value remains in
247     /// the aforementioned location in the vector register.
248     SCALAR_TO_VECTOR_PERMUTED,
249 
250     // FIXME: Remove these once the ANDI glue bug is fixed:
251     /// i1 = ANDI_rec_1_[EQ|GT]_BIT(i32 or i64 x) - Represents the result of the
252     /// eq or gt bit of CR0 after executing andi. x, 1. This is used to
253     /// implement truncation of i32 or i64 to i1.
254     ANDI_rec_1_EQ_BIT,
255     ANDI_rec_1_GT_BIT,
256 
257     // READ_TIME_BASE - A read of the 64-bit time-base register on a 32-bit
258     // target (returns (Lo, Hi)). It takes a chain operand.
259     READ_TIME_BASE,
260 
261     // EH_SJLJ_SETJMP - SjLj exception handling setjmp.
262     EH_SJLJ_SETJMP,
263 
264     // EH_SJLJ_LONGJMP - SjLj exception handling longjmp.
265     EH_SJLJ_LONGJMP,
266 
267     /// RESVEC = VCMP(LHS, RHS, OPC) - Represents one of the altivec VCMP*
268     /// instructions.  For lack of better number, we use the opcode number
269     /// encoding for the OPC field to identify the compare.  For example, 838
270     /// is VCMPGTSH.
271     VCMP,
272 
273     /// RESVEC, OUTFLAG = VCMP_rec(LHS, RHS, OPC) - Represents one of the
274     /// altivec VCMP*_rec instructions.  For lack of better number, we use the
275     /// opcode number encoding for the OPC field to identify the compare.  For
276     /// example, 838 is VCMPGTSH.
277     VCMP_rec,
278 
279     /// CHAIN = COND_BRANCH CHAIN, CRRC, OPC, DESTBB [, INFLAG] - This
280     /// corresponds to the COND_BRANCH pseudo instruction.  CRRC is the
281     /// condition register to branch on, OPC is the branch opcode to use (e.g.
282     /// PPC::BLE), DESTBB is the destination block to branch to, and INFLAG is
283     /// an optional input flag argument.
284     COND_BRANCH,
285 
286     /// CHAIN = BDNZ CHAIN, DESTBB - These are used to create counter-based
287     /// loops.
288     BDNZ,
289     BDZ,
290 
291     /// F8RC = FADDRTZ F8RC, F8RC - This is an FADD done with rounding
292     /// towards zero.  Used only as part of the long double-to-int
293     /// conversion sequence.
294     FADDRTZ,
295 
296     /// F8RC = MFFS - This moves the FPSCR (not modeled) into the register.
297     MFFS,
298 
299     /// TC_RETURN - A tail call return.
300     ///   operand #0 chain
301     ///   operand #1 callee (register or absolute)
302     ///   operand #2 stack adjustment
303     ///   operand #3 optional in flag
304     TC_RETURN,
305 
306     /// ch, gl = CR6[UN]SET ch, inglue - Toggle CR bit 6 for SVR4 vararg calls
307     CR6SET,
308     CR6UNSET,
309 
310     /// GPRC = address of _GLOBAL_OFFSET_TABLE_. Used by initial-exec TLS
311     /// for non-position independent code on PPC32.
312     PPC32_GOT,
313 
314     /// GPRC = address of _GLOBAL_OFFSET_TABLE_. Used by general dynamic and
315     /// local dynamic TLS and position indendepent code on PPC32.
316     PPC32_PICGOT,
317 
318     /// G8RC = ADDIS_GOT_TPREL_HA %x2, Symbol - Used by the initial-exec
319     /// TLS model, produces an ADDIS8 instruction that adds the GOT
320     /// base to sym\@got\@tprel\@ha.
321     ADDIS_GOT_TPREL_HA,
322 
323     /// G8RC = LD_GOT_TPREL_L Symbol, G8RReg - Used by the initial-exec
324     /// TLS model, produces a LD instruction with base register G8RReg
325     /// and offset sym\@got\@tprel\@l.  This completes the addition that
326     /// finds the offset of "sym" relative to the thread pointer.
327     LD_GOT_TPREL_L,
328 
329     /// G8RC = ADD_TLS G8RReg, Symbol - Used by the initial-exec TLS
330     /// model, produces an ADD instruction that adds the contents of
331     /// G8RReg to the thread pointer.  Symbol contains a relocation
332     /// sym\@tls which is to be replaced by the thread pointer and
333     /// identifies to the linker that the instruction is part of a
334     /// TLS sequence.
335     ADD_TLS,
336 
337     /// G8RC = ADDIS_TLSGD_HA %x2, Symbol - For the general-dynamic TLS
338     /// model, produces an ADDIS8 instruction that adds the GOT base
339     /// register to sym\@got\@tlsgd\@ha.
340     ADDIS_TLSGD_HA,
341 
342     /// %x3 = ADDI_TLSGD_L G8RReg, Symbol - For the general-dynamic TLS
343     /// model, produces an ADDI8 instruction that adds G8RReg to
344     /// sym\@got\@tlsgd\@l and stores the result in X3.  Hidden by
345     /// ADDIS_TLSGD_L_ADDR until after register assignment.
346     ADDI_TLSGD_L,
347 
348     /// %x3 = GET_TLS_ADDR %x3, Symbol - For the general-dynamic TLS
349     /// model, produces a call to __tls_get_addr(sym\@tlsgd).  Hidden by
350     /// ADDIS_TLSGD_L_ADDR until after register assignment.
351     GET_TLS_ADDR,
352 
353     /// G8RC = ADDI_TLSGD_L_ADDR G8RReg, Symbol, Symbol - Op that
354     /// combines ADDI_TLSGD_L and GET_TLS_ADDR until expansion following
355     /// register assignment.
356     ADDI_TLSGD_L_ADDR,
357 
358     /// G8RC = ADDIS_TLSLD_HA %x2, Symbol - For the local-dynamic TLS
359     /// model, produces an ADDIS8 instruction that adds the GOT base
360     /// register to sym\@got\@tlsld\@ha.
361     ADDIS_TLSLD_HA,
362 
363     /// %x3 = ADDI_TLSLD_L G8RReg, Symbol - For the local-dynamic TLS
364     /// model, produces an ADDI8 instruction that adds G8RReg to
365     /// sym\@got\@tlsld\@l and stores the result in X3.  Hidden by
366     /// ADDIS_TLSLD_L_ADDR until after register assignment.
367     ADDI_TLSLD_L,
368 
369     /// %x3 = GET_TLSLD_ADDR %x3, Symbol - For the local-dynamic TLS
370     /// model, produces a call to __tls_get_addr(sym\@tlsld).  Hidden by
371     /// ADDIS_TLSLD_L_ADDR until after register assignment.
372     GET_TLSLD_ADDR,
373 
374     /// G8RC = ADDI_TLSLD_L_ADDR G8RReg, Symbol, Symbol - Op that
375     /// combines ADDI_TLSLD_L and GET_TLSLD_ADDR until expansion
376     /// following register assignment.
377     ADDI_TLSLD_L_ADDR,
378 
379     /// G8RC = ADDIS_DTPREL_HA %x3, Symbol - For the local-dynamic TLS
380     /// model, produces an ADDIS8 instruction that adds X3 to
381     /// sym\@dtprel\@ha.
382     ADDIS_DTPREL_HA,
383 
384     /// G8RC = ADDI_DTPREL_L G8RReg, Symbol - For the local-dynamic TLS
385     /// model, produces an ADDI8 instruction that adds G8RReg to
386     /// sym\@got\@dtprel\@l.
387     ADDI_DTPREL_L,
388 
389     /// G8RC = PADDI_DTPREL %x3, Symbol - For the pc-rel based local-dynamic TLS
390     /// model, produces a PADDI8 instruction that adds X3 to sym\@dtprel.
391     PADDI_DTPREL,
392 
393     /// VRRC = VADD_SPLAT Elt, EltSize - Temporary node to be expanded
394     /// during instruction selection to optimize a BUILD_VECTOR into
395     /// operations on splats.  This is necessary to avoid losing these
396     /// optimizations due to constant folding.
397     VADD_SPLAT,
398 
399     /// CHAIN = SC CHAIN, Imm128 - System call.  The 7-bit unsigned
400     /// operand identifies the operating system entry point.
401     SC,
402 
403     /// CHAIN = CLRBHRB CHAIN - Clear branch history rolling buffer.
404     CLRBHRB,
405 
406     /// GPRC, CHAIN = MFBHRBE CHAIN, Entry, Dummy - Move from branch
407     /// history rolling buffer entry.
408     MFBHRBE,
409 
410     /// CHAIN = RFEBB CHAIN, State - Return from event-based branch.
411     RFEBB,
412 
413     /// VSRC, CHAIN = XXSWAPD CHAIN, VSRC - Occurs only for little
414     /// endian.  Maps to an xxswapd instruction that corrects an lxvd2x
415     /// or stxvd2x instruction.  The chain is necessary because the
416     /// sequence replaces a load and needs to provide the same number
417     /// of outputs.
418     XXSWAPD,
419 
420     /// An SDNode for swaps that are not associated with any loads/stores
421     /// and thereby have no chain.
422     SWAP_NO_CHAIN,
423 
424     /// An SDNode for Power9 vector absolute value difference.
425     /// operand #0 vector
426     /// operand #1 vector
427     /// operand #2 constant i32 0 or 1, to indicate whether needs to patch
428     /// the most significant bit for signed i32
429     ///
430     /// Power9 VABSD* instructions are designed to support unsigned integer
431     /// vectors (byte/halfword/word), if we want to make use of them for signed
432     /// integer vectors, we have to flip their sign bits first. To flip sign bit
433     /// for byte/halfword integer vector would become inefficient, but for word
434     /// integer vector, we can leverage XVNEGSP to make it efficiently. eg:
435     /// abs(sub(a,b)) => VABSDUW(a+0x80000000, b+0x80000000)
436     ///               => VABSDUW((XVNEGSP a), (XVNEGSP b))
437     VABSD,
438 
439     /// FP_EXTEND_HALF(VECTOR, IDX) - Custom extend upper (IDX=0) half or
440     /// lower (IDX=1) half of v4f32 to v2f64.
441     FP_EXTEND_HALF,
442 
443     /// MAT_PCREL_ADDR = Materialize a PC Relative address. This can be done
444     /// either through an add like PADDI or through a PC Relative load like
445     /// PLD.
446     MAT_PCREL_ADDR,
447 
448     /// TLS_DYNAMIC_MAT_PCREL_ADDR = Materialize a PC Relative address for
449     /// TLS global address when using dynamic access models. This can be done
450     /// through an add like PADDI.
451     TLS_DYNAMIC_MAT_PCREL_ADDR,
452 
453     /// TLS_LOCAL_EXEC_MAT_ADDR = Materialize an address for TLS global address
454     /// when using local exec access models, and when prefixed instructions are
455     /// available. This is used with ADD_TLS to produce an add like PADDI.
456     TLS_LOCAL_EXEC_MAT_ADDR,
457 
458     /// ACC_BUILD = Build an accumulator register from 4 VSX registers.
459     ACC_BUILD,
460 
461     /// PAIR_BUILD = Build a vector pair register from 2 VSX registers.
462     PAIR_BUILD,
463 
464     /// EXTRACT_VSX_REG = Extract one of the underlying vsx registers of
465     /// an accumulator or pair register. This node is needed because
466     /// EXTRACT_SUBVECTOR expects the input and output vectors to have the same
467     /// element type.
468     EXTRACT_VSX_REG,
469 
470     /// XXMFACC = This corresponds to the xxmfacc instruction.
471     XXMFACC,
472 
473     // Constrained conversion from floating point to int
474     STRICT_FCTIDZ = ISD::FIRST_TARGET_STRICTFP_OPCODE,
475     STRICT_FCTIWZ,
476     STRICT_FCTIDUZ,
477     STRICT_FCTIWUZ,
478 
479     /// Constrained integer-to-floating-point conversion instructions.
480     STRICT_FCFID,
481     STRICT_FCFIDU,
482     STRICT_FCFIDS,
483     STRICT_FCFIDUS,
484 
485     /// Constrained floating point add in round-to-zero mode.
486     STRICT_FADDRTZ,
487 
488     /// CHAIN = STBRX CHAIN, GPRC, Ptr, Type - This is a
489     /// byte-swapping store instruction.  It byte-swaps the low "Type" bits of
490     /// the GPRC input, then stores it through Ptr.  Type can be either i16 or
491     /// i32.
492     STBRX = ISD::FIRST_TARGET_MEMORY_OPCODE,
493 
494     /// GPRC, CHAIN = LBRX CHAIN, Ptr, Type - This is a
495     /// byte-swapping load instruction.  It loads "Type" bits, byte swaps it,
496     /// then puts it in the bottom bits of the GPRC.  TYPE can be either i16
497     /// or i32.
498     LBRX,
499 
500     /// STFIWX - The STFIWX instruction.  The first operand is an input token
501     /// chain, then an f64 value to store, then an address to store it to.
502     STFIWX,
503 
504     /// GPRC, CHAIN = LFIWAX CHAIN, Ptr - This is a floating-point
505     /// load which sign-extends from a 32-bit integer value into the
506     /// destination 64-bit register.
507     LFIWAX,
508 
509     /// GPRC, CHAIN = LFIWZX CHAIN, Ptr - This is a floating-point
510     /// load which zero-extends from a 32-bit integer value into the
511     /// destination 64-bit register.
512     LFIWZX,
513 
514     /// GPRC, CHAIN = LXSIZX, CHAIN, Ptr, ByteWidth - This is a load of an
515     /// integer smaller than 64 bits into a VSR. The integer is zero-extended.
516     /// This can be used for converting loaded integers to floating point.
517     LXSIZX,
518 
519     /// STXSIX - The STXSI[bh]X instruction. The first operand is an input
520     /// chain, then an f64 value to store, then an address to store it to,
521     /// followed by a byte-width for the store.
522     STXSIX,
523 
524     /// VSRC, CHAIN = LXVD2X_LE CHAIN, Ptr - Occurs only for little endian.
525     /// Maps directly to an lxvd2x instruction that will be followed by
526     /// an xxswapd.
527     LXVD2X,
528 
529     /// LXVRZX - Load VSX Vector Rightmost and Zero Extend
530     /// This node represents v1i128 BUILD_VECTOR of a zero extending load
531     /// instruction from <byte, halfword, word, or doubleword> to i128.
532     /// Allows utilization of the Load VSX Vector Rightmost Instructions.
533     LXVRZX,
534 
535     /// VSRC, CHAIN = LOAD_VEC_BE CHAIN, Ptr - Occurs only for little endian.
536     /// Maps directly to one of lxvd2x/lxvw4x/lxvh8x/lxvb16x depending on
537     /// the vector type to load vector in big-endian element order.
538     LOAD_VEC_BE,
539 
540     /// VSRC, CHAIN = LD_VSX_LH CHAIN, Ptr - This is a floating-point load of a
541     /// v2f32 value into the lower half of a VSR register.
542     LD_VSX_LH,
543 
544     /// VSRC, CHAIN = LD_SPLAT, CHAIN, Ptr - a splatting load memory
545     /// instructions such as LXVDSX, LXVWSX.
546     LD_SPLAT,
547 
548     /// CHAIN = STXVD2X CHAIN, VSRC, Ptr - Occurs only for little endian.
549     /// Maps directly to an stxvd2x instruction that will be preceded by
550     /// an xxswapd.
551     STXVD2X,
552 
553     /// CHAIN = STORE_VEC_BE CHAIN, VSRC, Ptr - Occurs only for little endian.
554     /// Maps directly to one of stxvd2x/stxvw4x/stxvh8x/stxvb16x depending on
555     /// the vector type to store vector in big-endian element order.
556     STORE_VEC_BE,
557 
558     /// Store scalar integers from VSR.
559     ST_VSR_SCAL_INT,
560 
561     /// ATOMIC_CMP_SWAP - the exact same as the target-independent nodes
562     /// except they ensure that the compare input is zero-extended for
563     /// sub-word versions because the atomic loads zero-extend.
564     ATOMIC_CMP_SWAP_8,
565     ATOMIC_CMP_SWAP_16,
566 
567     /// GPRC = TOC_ENTRY GA, TOC
568     /// Loads the entry for GA from the TOC, where the TOC base is given by
569     /// the last operand.
570     TOC_ENTRY
571   };
572 
573   } // end namespace PPCISD
574 
575   /// Define some predicates that are used for node matching.
576   namespace PPC {
577 
578     /// isVPKUHUMShuffleMask - Return true if this is the shuffle mask for a
579     /// VPKUHUM instruction.
580     bool isVPKUHUMShuffleMask(ShuffleVectorSDNode *N, unsigned ShuffleKind,
581                               SelectionDAG &DAG);
582 
583     /// isVPKUWUMShuffleMask - Return true if this is the shuffle mask for a
584     /// VPKUWUM instruction.
585     bool isVPKUWUMShuffleMask(ShuffleVectorSDNode *N, unsigned ShuffleKind,
586                               SelectionDAG &DAG);
587 
588     /// isVPKUDUMShuffleMask - Return true if this is the shuffle mask for a
589     /// VPKUDUM instruction.
590     bool isVPKUDUMShuffleMask(ShuffleVectorSDNode *N, unsigned ShuffleKind,
591                               SelectionDAG &DAG);
592 
593     /// isVMRGLShuffleMask - Return true if this is a shuffle mask suitable for
594     /// a VRGL* instruction with the specified unit size (1,2 or 4 bytes).
595     bool isVMRGLShuffleMask(ShuffleVectorSDNode *N, unsigned UnitSize,
596                             unsigned ShuffleKind, SelectionDAG &DAG);
597 
598     /// isVMRGHShuffleMask - Return true if this is a shuffle mask suitable for
599     /// a VRGH* instruction with the specified unit size (1,2 or 4 bytes).
600     bool isVMRGHShuffleMask(ShuffleVectorSDNode *N, unsigned UnitSize,
601                             unsigned ShuffleKind, SelectionDAG &DAG);
602 
603     /// isVMRGEOShuffleMask - Return true if this is a shuffle mask suitable for
604     /// a VMRGEW or VMRGOW instruction
605     bool isVMRGEOShuffleMask(ShuffleVectorSDNode *N, bool CheckEven,
606                              unsigned ShuffleKind, SelectionDAG &DAG);
607     /// isXXSLDWIShuffleMask - Return true if this is a shuffle mask suitable
608     /// for a XXSLDWI instruction.
609     bool isXXSLDWIShuffleMask(ShuffleVectorSDNode *N, unsigned &ShiftElts,
610                               bool &Swap, bool IsLE);
611 
612     /// isXXBRHShuffleMask - Return true if this is a shuffle mask suitable
613     /// for a XXBRH instruction.
614     bool isXXBRHShuffleMask(ShuffleVectorSDNode *N);
615 
616     /// isXXBRWShuffleMask - Return true if this is a shuffle mask suitable
617     /// for a XXBRW instruction.
618     bool isXXBRWShuffleMask(ShuffleVectorSDNode *N);
619 
620     /// isXXBRDShuffleMask - Return true if this is a shuffle mask suitable
621     /// for a XXBRD instruction.
622     bool isXXBRDShuffleMask(ShuffleVectorSDNode *N);
623 
624     /// isXXBRQShuffleMask - Return true if this is a shuffle mask suitable
625     /// for a XXBRQ instruction.
626     bool isXXBRQShuffleMask(ShuffleVectorSDNode *N);
627 
628     /// isXXPERMDIShuffleMask - Return true if this is a shuffle mask suitable
629     /// for a XXPERMDI instruction.
630     bool isXXPERMDIShuffleMask(ShuffleVectorSDNode *N, unsigned &ShiftElts,
631                               bool &Swap, bool IsLE);
632 
633     /// isVSLDOIShuffleMask - If this is a vsldoi shuffle mask, return the
634     /// shift amount, otherwise return -1.
635     int isVSLDOIShuffleMask(SDNode *N, unsigned ShuffleKind,
636                             SelectionDAG &DAG);
637 
638     /// isSplatShuffleMask - Return true if the specified VECTOR_SHUFFLE operand
639     /// specifies a splat of a single element that is suitable for input to
640     /// VSPLTB/VSPLTH/VSPLTW.
641     bool isSplatShuffleMask(ShuffleVectorSDNode *N, unsigned EltSize);
642 
643     /// isXXINSERTWMask - Return true if this VECTOR_SHUFFLE can be handled by
644     /// the XXINSERTW instruction introduced in ISA 3.0. This is essentially any
645     /// shuffle of v4f32/v4i32 vectors that just inserts one element from one
646     /// vector into the other. This function will also set a couple of
647     /// output parameters for how much the source vector needs to be shifted and
648     /// what byte number needs to be specified for the instruction to put the
649     /// element in the desired location of the target vector.
650     bool isXXINSERTWMask(ShuffleVectorSDNode *N, unsigned &ShiftElts,
651                          unsigned &InsertAtByte, bool &Swap, bool IsLE);
652 
653     /// getSplatIdxForPPCMnemonics - Return the splat index as a value that is
654     /// appropriate for PPC mnemonics (which have a big endian bias - namely
655     /// elements are counted from the left of the vector register).
656     unsigned getSplatIdxForPPCMnemonics(SDNode *N, unsigned EltSize,
657                                         SelectionDAG &DAG);
658 
659     /// get_VSPLTI_elt - If this is a build_vector of constants which can be
660     /// formed by using a vspltis[bhw] instruction of the specified element
661     /// size, return the constant being splatted.  The ByteSize field indicates
662     /// the number of bytes of each element [124] -> [bhw].
663     SDValue get_VSPLTI_elt(SDNode *N, unsigned ByteSize, SelectionDAG &DAG);
664 
665   } // end namespace PPC
666 
667   class PPCTargetLowering : public TargetLowering {
668     const PPCSubtarget &Subtarget;
669 
670   public:
671     explicit PPCTargetLowering(const PPCTargetMachine &TM,
672                                const PPCSubtarget &STI);
673 
674     /// getTargetNodeName() - This method returns the name of a target specific
675     /// DAG node.
676     const char *getTargetNodeName(unsigned Opcode) const override;
677 
678     bool isSelectSupported(SelectSupportKind Kind) const override {
679       // PowerPC does not support scalar condition selects on vectors.
680       return (Kind != SelectSupportKind::ScalarCondVectorVal);
681     }
682 
683     /// getPreferredVectorAction - The code we generate when vector types are
684     /// legalized by promoting the integer element type is often much worse
685     /// than code we generate if we widen the type for applicable vector types.
686     /// The issue with promoting is that the vector is scalaraized, individual
687     /// elements promoted and then the vector is rebuilt. So say we load a pair
688     /// of v4i8's and shuffle them. This will turn into a mess of 8 extending
689     /// loads, moves back into VSR's (or memory ops if we don't have moves) and
690     /// then the VPERM for the shuffle. All in all a very slow sequence.
691     TargetLoweringBase::LegalizeTypeAction getPreferredVectorAction(MVT VT)
692       const override {
693       if (VT.getVectorNumElements() != 1 && VT.getScalarSizeInBits() % 8 == 0)
694         return TypeWidenVector;
695       return TargetLoweringBase::getPreferredVectorAction(VT);
696     }
697 
698     bool useSoftFloat() const override;
699 
700     bool hasSPE() const;
701 
702     MVT getScalarShiftAmountTy(const DataLayout &, EVT) const override {
703       return MVT::i32;
704     }
705 
706     bool isCheapToSpeculateCttz() const override {
707       return true;
708     }
709 
710     bool isCheapToSpeculateCtlz() const override {
711       return true;
712     }
713 
714     bool isCtlzFast() const override {
715       return true;
716     }
717 
718     bool isEqualityCmpFoldedWithSignedCmp() const override {
719       return false;
720     }
721 
722     bool hasAndNotCompare(SDValue) const override {
723       return true;
724     }
725 
726     bool preferIncOfAddToSubOfNot(EVT VT) const override;
727 
728     bool convertSetCCLogicToBitwiseLogic(EVT VT) const override {
729       return VT.isScalarInteger();
730     }
731 
732     SDValue getNegatedExpression(SDValue Op, SelectionDAG &DAG, bool LegalOps,
733                                  bool OptForSize, NegatibleCost &Cost,
734                                  unsigned Depth = 0) const override;
735 
736     /// getSetCCResultType - Return the ISD::SETCC ValueType
737     EVT getSetCCResultType(const DataLayout &DL, LLVMContext &Context,
738                            EVT VT) const override;
739 
740     /// Return true if target always beneficiates from combining into FMA for a
741     /// given value type. This must typically return false on targets where FMA
742     /// takes more cycles to execute than FADD.
743     bool enableAggressiveFMAFusion(EVT VT) const override;
744 
745     /// getPreIndexedAddressParts - returns true by value, base pointer and
746     /// offset pointer and addressing mode by reference if the node's address
747     /// can be legally represented as pre-indexed load / store address.
748     bool getPreIndexedAddressParts(SDNode *N, SDValue &Base,
749                                    SDValue &Offset,
750                                    ISD::MemIndexedMode &AM,
751                                    SelectionDAG &DAG) const override;
752 
753     /// SelectAddressEVXRegReg - Given the specified addressed, check to see if
754     /// it can be more efficiently represented as [r+imm].
755     bool SelectAddressEVXRegReg(SDValue N, SDValue &Base, SDValue &Index,
756                                 SelectionDAG &DAG) const;
757 
758     /// SelectAddressRegReg - Given the specified addressed, check to see if it
759     /// can be more efficiently represented as [r+imm]. If \p EncodingAlignment
760     /// is non-zero, only accept displacement which is not suitable for [r+imm].
761     /// Returns false if it can be represented by [r+imm], which are preferred.
762     bool SelectAddressRegReg(SDValue N, SDValue &Base, SDValue &Index,
763                              SelectionDAG &DAG,
764                              MaybeAlign EncodingAlignment = None) const;
765 
766     /// SelectAddressRegImm - Returns true if the address N can be represented
767     /// by a base register plus a signed 16-bit displacement [r+imm], and if it
768     /// is not better represented as reg+reg. If \p EncodingAlignment is
769     /// non-zero, only accept displacements suitable for instruction encoding
770     /// requirement, i.e. multiples of 4 for DS form.
771     bool SelectAddressRegImm(SDValue N, SDValue &Disp, SDValue &Base,
772                              SelectionDAG &DAG,
773                              MaybeAlign EncodingAlignment) const;
774     bool SelectAddressRegImm34(SDValue N, SDValue &Disp, SDValue &Base,
775                                SelectionDAG &DAG) const;
776 
777     /// SelectAddressRegRegOnly - Given the specified addressed, force it to be
778     /// represented as an indexed [r+r] operation.
779     bool SelectAddressRegRegOnly(SDValue N, SDValue &Base, SDValue &Index,
780                                  SelectionDAG &DAG) const;
781 
782     /// SelectAddressPCRel - Represent the specified address as pc relative to
783     /// be represented as [pc+imm]
784     bool SelectAddressPCRel(SDValue N, SDValue &Base) const;
785 
786     Sched::Preference getSchedulingPreference(SDNode *N) const override;
787 
788     /// LowerOperation - Provide custom lowering hooks for some operations.
789     ///
790     SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;
791 
792     /// ReplaceNodeResults - Replace the results of node with an illegal result
793     /// type with new values built out of custom code.
794     ///
795     void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue>&Results,
796                             SelectionDAG &DAG) const override;
797 
798     SDValue expandVSXLoadForLE(SDNode *N, DAGCombinerInfo &DCI) const;
799     SDValue expandVSXStoreForLE(SDNode *N, DAGCombinerInfo &DCI) const;
800 
801     SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const override;
802 
803     SDValue BuildSDIVPow2(SDNode *N, const APInt &Divisor, SelectionDAG &DAG,
804                           SmallVectorImpl<SDNode *> &Created) const override;
805 
806     Register getRegisterByName(const char* RegName, LLT VT,
807                                const MachineFunction &MF) const override;
808 
809     void computeKnownBitsForTargetNode(const SDValue Op,
810                                        KnownBits &Known,
811                                        const APInt &DemandedElts,
812                                        const SelectionDAG &DAG,
813                                        unsigned Depth = 0) const override;
814 
815     Align getPrefLoopAlignment(MachineLoop *ML) const override;
816 
817     bool shouldInsertFencesForAtomic(const Instruction *I) const override {
818       return true;
819     }
820 
821     Instruction *emitLeadingFence(IRBuilder<> &Builder, Instruction *Inst,
822                                   AtomicOrdering Ord) const override;
823     Instruction *emitTrailingFence(IRBuilder<> &Builder, Instruction *Inst,
824                                    AtomicOrdering Ord) const override;
825 
826     MachineBasicBlock *
827     EmitInstrWithCustomInserter(MachineInstr &MI,
828                                 MachineBasicBlock *MBB) const override;
829     MachineBasicBlock *EmitAtomicBinary(MachineInstr &MI,
830                                         MachineBasicBlock *MBB,
831                                         unsigned AtomicSize,
832                                         unsigned BinOpcode,
833                                         unsigned CmpOpcode = 0,
834                                         unsigned CmpPred = 0) const;
835     MachineBasicBlock *EmitPartwordAtomicBinary(MachineInstr &MI,
836                                                 MachineBasicBlock *MBB,
837                                                 bool is8bit,
838                                                 unsigned Opcode,
839                                                 unsigned CmpOpcode = 0,
840                                                 unsigned CmpPred = 0) const;
841 
842     MachineBasicBlock *emitEHSjLjSetJmp(MachineInstr &MI,
843                                         MachineBasicBlock *MBB) const;
844 
845     MachineBasicBlock *emitEHSjLjLongJmp(MachineInstr &MI,
846                                          MachineBasicBlock *MBB) const;
847 
848     MachineBasicBlock *emitProbedAlloca(MachineInstr &MI,
849                                         MachineBasicBlock *MBB) const;
850 
851     bool hasInlineStackProbe(MachineFunction &MF) const override;
852 
853     unsigned getStackProbeSize(MachineFunction &MF) const;
854 
855     ConstraintType getConstraintType(StringRef Constraint) const override;
856 
857     /// Examine constraint string and operand type and determine a weight value.
858     /// The operand object must already have been set up with the operand type.
859     ConstraintWeight getSingleConstraintMatchWeight(
860       AsmOperandInfo &info, const char *constraint) const override;
861 
862     std::pair<unsigned, const TargetRegisterClass *>
863     getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
864                                  StringRef Constraint, MVT VT) const override;
865 
866     /// getByValTypeAlignment - Return the desired alignment for ByVal aggregate
867     /// function arguments in the caller parameter area.  This is the actual
868     /// alignment, not its logarithm.
869     unsigned getByValTypeAlignment(Type *Ty,
870                                    const DataLayout &DL) const override;
871 
872     /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
873     /// vector.  If it is invalid, don't add anything to Ops.
874     void LowerAsmOperandForConstraint(SDValue Op,
875                                       std::string &Constraint,
876                                       std::vector<SDValue> &Ops,
877                                       SelectionDAG &DAG) const override;
878 
879     unsigned
880     getInlineAsmMemConstraint(StringRef ConstraintCode) const override {
881       if (ConstraintCode == "es")
882         return InlineAsm::Constraint_es;
883       else if (ConstraintCode == "o")
884         return InlineAsm::Constraint_o;
885       else if (ConstraintCode == "Q")
886         return InlineAsm::Constraint_Q;
887       else if (ConstraintCode == "Z")
888         return InlineAsm::Constraint_Z;
889       else if (ConstraintCode == "Zy")
890         return InlineAsm::Constraint_Zy;
891       return TargetLowering::getInlineAsmMemConstraint(ConstraintCode);
892     }
893 
894     /// isLegalAddressingMode - Return true if the addressing mode represented
895     /// by AM is legal for this target, for a load/store of the specified type.
896     bool isLegalAddressingMode(const DataLayout &DL, const AddrMode &AM,
897                                Type *Ty, unsigned AS,
898                                Instruction *I = nullptr) const override;
899 
900     /// isLegalICmpImmediate - Return true if the specified immediate is legal
901     /// icmp immediate, that is the target has icmp instructions which can
902     /// compare a register against the immediate without having to materialize
903     /// the immediate into a register.
904     bool isLegalICmpImmediate(int64_t Imm) const override;
905 
906     /// isLegalAddImmediate - Return true if the specified immediate is legal
907     /// add immediate, that is the target has add instructions which can
908     /// add a register and the immediate without having to materialize
909     /// the immediate into a register.
910     bool isLegalAddImmediate(int64_t Imm) const override;
911 
912     /// isTruncateFree - Return true if it's free to truncate a value of
913     /// type Ty1 to type Ty2. e.g. On PPC it's free to truncate a i64 value in
914     /// register X1 to i32 by referencing its sub-register R1.
915     bool isTruncateFree(Type *Ty1, Type *Ty2) const override;
916     bool isTruncateFree(EVT VT1, EVT VT2) const override;
917 
918     bool isZExtFree(SDValue Val, EVT VT2) const override;
919 
920     bool isFPExtFree(EVT DestVT, EVT SrcVT) const override;
921 
922     /// Returns true if it is beneficial to convert a load of a constant
923     /// to just the constant itself.
924     bool shouldConvertConstantLoadToIntImm(const APInt &Imm,
925                                            Type *Ty) const override;
926 
927     bool convertSelectOfConstantsToMath(EVT VT) const override {
928       return true;
929     }
930 
931     bool decomposeMulByConstant(LLVMContext &Context, EVT VT,
932                                 SDValue C) const override;
933 
934     bool isDesirableToTransformToIntegerOp(unsigned Opc,
935                                            EVT VT) const override {
936       // Only handle float load/store pair because float(fpr) load/store
937       // instruction has more cycles than integer(gpr) load/store in PPC.
938       if (Opc != ISD::LOAD && Opc != ISD::STORE)
939         return false;
940       if (VT != MVT::f32 && VT != MVT::f64)
941         return false;
942 
943       return true;
944     }
945 
946     // Returns true if the address of the global is stored in TOC entry.
947     bool isAccessedAsGotIndirect(SDValue N) const;
948 
949     bool isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const override;
950 
951     bool getTgtMemIntrinsic(IntrinsicInfo &Info,
952                             const CallInst &I,
953                             MachineFunction &MF,
954                             unsigned Intrinsic) const override;
955 
956     /// It returns EVT::Other if the type should be determined using generic
957     /// target-independent logic.
958     EVT getOptimalMemOpType(const MemOp &Op,
959                             const AttributeList &FuncAttributes) const override;
960 
961     /// Is unaligned memory access allowed for the given type, and is it fast
962     /// relative to software emulation.
963     bool allowsMisalignedMemoryAccesses(
964         EVT VT, unsigned AddrSpace, unsigned Align = 1,
965         MachineMemOperand::Flags Flags = MachineMemOperand::MONone,
966         bool *Fast = nullptr) const override;
967 
968     /// isFMAFasterThanFMulAndFAdd - Return true if an FMA operation is faster
969     /// than a pair of fmul and fadd instructions. fmuladd intrinsics will be
970     /// expanded to FMAs when this method returns true, otherwise fmuladd is
971     /// expanded to fmul + fadd.
972     bool isFMAFasterThanFMulAndFAdd(const MachineFunction &MF,
973                                     EVT VT) const override;
974 
975     bool isFMAFasterThanFMulAndFAdd(const Function &F, Type *Ty) const override;
976 
977     /// isProfitableToHoist - Check if it is profitable to hoist instruction
978     /// \p I to its dominator block.
979     /// For example, it is not profitable if \p I and it's only user can form a
980     /// FMA instruction, because Powerpc prefers FMADD.
981     bool isProfitableToHoist(Instruction *I) const override;
982 
983     const MCPhysReg *getScratchRegisters(CallingConv::ID CC) const override;
984 
985     // Should we expand the build vector with shuffles?
986     bool
987     shouldExpandBuildVectorWithShuffles(EVT VT,
988                                         unsigned DefinedValues) const override;
989 
990     // Keep the zero-extensions for arguments to libcalls.
991     bool shouldKeepZExtForFP16Conv() const override { return true; }
992 
993     /// createFastISel - This method returns a target-specific FastISel object,
994     /// or null if the target does not support "fast" instruction selection.
995     FastISel *createFastISel(FunctionLoweringInfo &FuncInfo,
996                              const TargetLibraryInfo *LibInfo) const override;
997 
998     /// Returns true if an argument of type Ty needs to be passed in a
999     /// contiguous block of registers in calling convention CallConv.
1000     bool functionArgumentNeedsConsecutiveRegisters(
1001       Type *Ty, CallingConv::ID CallConv, bool isVarArg) const override {
1002       // We support any array type as "consecutive" block in the parameter
1003       // save area.  The element type defines the alignment requirement and
1004       // whether the argument should go in GPRs, FPRs, or VRs if available.
1005       //
1006       // Note that clang uses this capability both to implement the ELFv2
1007       // homogeneous float/vector aggregate ABI, and to avoid having to use
1008       // "byval" when passing aggregates that might fully fit in registers.
1009       return Ty->isArrayTy();
1010     }
1011 
1012     /// If a physical register, this returns the register that receives the
1013     /// exception address on entry to an EH pad.
1014     Register
1015     getExceptionPointerRegister(const Constant *PersonalityFn) const override;
1016 
1017     /// If a physical register, this returns the register that receives the
1018     /// exception typeid on entry to a landing pad.
1019     Register
1020     getExceptionSelectorRegister(const Constant *PersonalityFn) const override;
1021 
1022     /// Override to support customized stack guard loading.
1023     bool useLoadStackGuardNode() const override;
1024     void insertSSPDeclarations(Module &M) const override;
1025 
1026     bool isFPImmLegal(const APFloat &Imm, EVT VT,
1027                       bool ForCodeSize) const override;
1028 
1029     unsigned getJumpTableEncoding() const override;
1030     bool isJumpTableRelative() const override;
1031     SDValue getPICJumpTableRelocBase(SDValue Table,
1032                                      SelectionDAG &DAG) const override;
1033     const MCExpr *getPICJumpTableRelocBaseExpr(const MachineFunction *MF,
1034                                                unsigned JTI,
1035                                                MCContext &Ctx) const override;
1036 
1037     /// Structure that collects some common arguments that get passed around
1038     /// between the functions for call lowering.
1039     struct CallFlags {
1040       const CallingConv::ID CallConv;
1041       const bool IsTailCall : 1;
1042       const bool IsVarArg : 1;
1043       const bool IsPatchPoint : 1;
1044       const bool IsIndirect : 1;
1045       const bool HasNest : 1;
1046       const bool NoMerge : 1;
1047 
1048       CallFlags(CallingConv::ID CC, bool IsTailCall, bool IsVarArg,
1049                 bool IsPatchPoint, bool IsIndirect, bool HasNest, bool NoMerge)
1050           : CallConv(CC), IsTailCall(IsTailCall), IsVarArg(IsVarArg),
1051             IsPatchPoint(IsPatchPoint), IsIndirect(IsIndirect),
1052             HasNest(HasNest), NoMerge(NoMerge) {}
1053     };
1054 
1055   private:
1056     struct ReuseLoadInfo {
1057       SDValue Ptr;
1058       SDValue Chain;
1059       SDValue ResChain;
1060       MachinePointerInfo MPI;
1061       bool IsDereferenceable = false;
1062       bool IsInvariant = false;
1063       Align Alignment;
1064       AAMDNodes AAInfo;
1065       const MDNode *Ranges = nullptr;
1066 
1067       ReuseLoadInfo() = default;
1068 
1069       MachineMemOperand::Flags MMOFlags() const {
1070         MachineMemOperand::Flags F = MachineMemOperand::MONone;
1071         if (IsDereferenceable)
1072           F |= MachineMemOperand::MODereferenceable;
1073         if (IsInvariant)
1074           F |= MachineMemOperand::MOInvariant;
1075         return F;
1076       }
1077     };
1078 
1079     bool canReuseLoadAddress(SDValue Op, EVT MemVT, ReuseLoadInfo &RLI,
1080                              SelectionDAG &DAG,
1081                              ISD::LoadExtType ET = ISD::NON_EXTLOAD) const;
1082     void spliceIntoChain(SDValue ResChain, SDValue NewResChain,
1083                          SelectionDAG &DAG) const;
1084 
1085     void LowerFP_TO_INTForReuse(SDValue Op, ReuseLoadInfo &RLI,
1086                                 SelectionDAG &DAG, const SDLoc &dl) const;
1087     SDValue LowerFP_TO_INTDirectMove(SDValue Op, SelectionDAG &DAG,
1088                                      const SDLoc &dl) const;
1089 
1090     bool directMoveIsProfitable(const SDValue &Op) const;
1091     SDValue LowerINT_TO_FPDirectMove(SDValue Op, SelectionDAG &DAG,
1092                                      const SDLoc &dl) const;
1093 
1094     SDValue LowerINT_TO_FPVector(SDValue Op, SelectionDAG &DAG,
1095                                  const SDLoc &dl) const;
1096 
1097     SDValue LowerTRUNCATEVector(SDValue Op, SelectionDAG &DAG) const;
1098 
1099     SDValue getFramePointerFrameIndex(SelectionDAG & DAG) const;
1100     SDValue getReturnAddrFrameIndex(SelectionDAG & DAG) const;
1101 
1102     bool
1103     IsEligibleForTailCallOptimization(SDValue Callee,
1104                                       CallingConv::ID CalleeCC,
1105                                       bool isVarArg,
1106                                       const SmallVectorImpl<ISD::InputArg> &Ins,
1107                                       SelectionDAG& DAG) const;
1108 
1109     bool IsEligibleForTailCallOptimization_64SVR4(
1110         SDValue Callee, CallingConv::ID CalleeCC, const CallBase *CB,
1111         bool isVarArg, const SmallVectorImpl<ISD::OutputArg> &Outs,
1112         const SmallVectorImpl<ISD::InputArg> &Ins, SelectionDAG &DAG) const;
1113 
1114     SDValue EmitTailCallLoadFPAndRetAddr(SelectionDAG &DAG, int SPDiff,
1115                                          SDValue Chain, SDValue &LROpOut,
1116                                          SDValue &FPOpOut,
1117                                          const SDLoc &dl) const;
1118 
1119     SDValue getTOCEntry(SelectionDAG &DAG, const SDLoc &dl, SDValue GA) const;
1120 
1121     SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
1122     SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
1123     SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG) const;
1124     SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const;
1125     SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const;
1126     SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
1127     SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG) const;
1128     SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const;
1129     SDValue LowerINIT_TRAMPOLINE(SDValue Op, SelectionDAG &DAG) const;
1130     SDValue LowerADJUST_TRAMPOLINE(SDValue Op, SelectionDAG &DAG) const;
1131     SDValue LowerINLINEASM(SDValue Op, SelectionDAG &DAG) const;
1132     SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const;
1133     SDValue LowerVAARG(SDValue Op, SelectionDAG &DAG) const;
1134     SDValue LowerVACOPY(SDValue Op, SelectionDAG &DAG) const;
1135     SDValue LowerSTACKRESTORE(SDValue Op, SelectionDAG &DAG) const;
1136     SDValue LowerGET_DYNAMIC_AREA_OFFSET(SDValue Op, SelectionDAG &DAG) const;
1137     SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
1138     SDValue LowerEH_DWARF_CFA(SDValue Op, SelectionDAG &DAG) const;
1139     SDValue LowerLOAD(SDValue Op, SelectionDAG &DAG) const;
1140     SDValue LowerSTORE(SDValue Op, SelectionDAG &DAG) const;
1141     SDValue LowerTRUNCATE(SDValue Op, SelectionDAG &DAG) const;
1142     SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
1143     SDValue LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG,
1144                            const SDLoc &dl) const;
1145     SDValue LowerINT_TO_FP(SDValue Op, SelectionDAG &DAG) const;
1146     SDValue LowerFLT_ROUNDS_(SDValue Op, SelectionDAG &DAG) const;
1147     SDValue LowerSHL_PARTS(SDValue Op, SelectionDAG &DAG) const;
1148     SDValue LowerSRL_PARTS(SDValue Op, SelectionDAG &DAG) const;
1149     SDValue LowerSRA_PARTS(SDValue Op, SelectionDAG &DAG) const;
1150     SDValue LowerFunnelShift(SDValue Op, SelectionDAG &DAG) const;
1151     SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const;
1152     SDValue LowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG) const;
1153     SDValue LowerINSERT_VECTOR_ELT(SDValue Op, SelectionDAG &DAG) const;
1154     SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG) const;
1155     SDValue LowerINTRINSIC_VOID(SDValue Op, SelectionDAG &DAG) const;
1156     SDValue LowerBSWAP(SDValue Op, SelectionDAG &DAG) const;
1157     SDValue LowerATOMIC_CMP_SWAP(SDValue Op, SelectionDAG &DAG) const;
1158     SDValue LowerSCALAR_TO_VECTOR(SDValue Op, SelectionDAG &DAG) const;
1159     SDValue LowerMUL(SDValue Op, SelectionDAG &DAG) const;
1160     SDValue LowerFP_EXTEND(SDValue Op, SelectionDAG &DAG) const;
1161     SDValue LowerFP_ROUND(SDValue Op, SelectionDAG &DAG) const;
1162     SDValue LowerROTL(SDValue Op, SelectionDAG &DAG) const;
1163 
1164     SDValue LowerVectorLoad(SDValue Op, SelectionDAG &DAG) const;
1165     SDValue LowerVectorStore(SDValue Op, SelectionDAG &DAG) const;
1166 
1167     SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
1168                             CallingConv::ID CallConv, bool isVarArg,
1169                             const SmallVectorImpl<ISD::InputArg> &Ins,
1170                             const SDLoc &dl, SelectionDAG &DAG,
1171                             SmallVectorImpl<SDValue> &InVals) const;
1172 
1173     SDValue FinishCall(CallFlags CFlags, const SDLoc &dl, SelectionDAG &DAG,
1174                        SmallVector<std::pair<unsigned, SDValue>, 8> &RegsToPass,
1175                        SDValue InFlag, SDValue Chain, SDValue CallSeqStart,
1176                        SDValue &Callee, int SPDiff, unsigned NumBytes,
1177                        const SmallVectorImpl<ISD::InputArg> &Ins,
1178                        SmallVectorImpl<SDValue> &InVals,
1179                        const CallBase *CB) const;
1180 
1181     SDValue
1182     LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
1183                          const SmallVectorImpl<ISD::InputArg> &Ins,
1184                          const SDLoc &dl, SelectionDAG &DAG,
1185                          SmallVectorImpl<SDValue> &InVals) const override;
1186 
1187     SDValue LowerCall(TargetLowering::CallLoweringInfo &CLI,
1188                       SmallVectorImpl<SDValue> &InVals) const override;
1189 
1190     bool CanLowerReturn(CallingConv::ID CallConv, MachineFunction &MF,
1191                         bool isVarArg,
1192                         const SmallVectorImpl<ISD::OutputArg> &Outs,
1193                         LLVMContext &Context) const override;
1194 
1195     SDValue LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
1196                         const SmallVectorImpl<ISD::OutputArg> &Outs,
1197                         const SmallVectorImpl<SDValue> &OutVals,
1198                         const SDLoc &dl, SelectionDAG &DAG) const override;
1199 
1200     SDValue extendArgForPPC64(ISD::ArgFlagsTy Flags, EVT ObjectVT,
1201                               SelectionDAG &DAG, SDValue ArgVal,
1202                               const SDLoc &dl) const;
1203 
1204     SDValue LowerFormalArguments_AIX(
1205         SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
1206         const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
1207         SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const;
1208     SDValue LowerFormalArguments_64SVR4(
1209         SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
1210         const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
1211         SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const;
1212     SDValue LowerFormalArguments_32SVR4(
1213         SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
1214         const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
1215         SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const;
1216 
1217     SDValue createMemcpyOutsideCallSeq(SDValue Arg, SDValue PtrOff,
1218                                        SDValue CallSeqStart,
1219                                        ISD::ArgFlagsTy Flags, SelectionDAG &DAG,
1220                                        const SDLoc &dl) const;
1221 
1222     SDValue LowerCall_64SVR4(SDValue Chain, SDValue Callee, CallFlags CFlags,
1223                              const SmallVectorImpl<ISD::OutputArg> &Outs,
1224                              const SmallVectorImpl<SDValue> &OutVals,
1225                              const SmallVectorImpl<ISD::InputArg> &Ins,
1226                              const SDLoc &dl, SelectionDAG &DAG,
1227                              SmallVectorImpl<SDValue> &InVals,
1228                              const CallBase *CB) const;
1229     SDValue LowerCall_32SVR4(SDValue Chain, SDValue Callee, CallFlags CFlags,
1230                              const SmallVectorImpl<ISD::OutputArg> &Outs,
1231                              const SmallVectorImpl<SDValue> &OutVals,
1232                              const SmallVectorImpl<ISD::InputArg> &Ins,
1233                              const SDLoc &dl, SelectionDAG &DAG,
1234                              SmallVectorImpl<SDValue> &InVals,
1235                              const CallBase *CB) const;
1236     SDValue LowerCall_AIX(SDValue Chain, SDValue Callee, CallFlags CFlags,
1237                           const SmallVectorImpl<ISD::OutputArg> &Outs,
1238                           const SmallVectorImpl<SDValue> &OutVals,
1239                           const SmallVectorImpl<ISD::InputArg> &Ins,
1240                           const SDLoc &dl, SelectionDAG &DAG,
1241                           SmallVectorImpl<SDValue> &InVals,
1242                           const CallBase *CB) const;
1243 
1244     SDValue lowerEH_SJLJ_SETJMP(SDValue Op, SelectionDAG &DAG) const;
1245     SDValue lowerEH_SJLJ_LONGJMP(SDValue Op, SelectionDAG &DAG) const;
1246     SDValue LowerBITCAST(SDValue Op, SelectionDAG &DAG) const;
1247 
1248     SDValue DAGCombineExtBoolTrunc(SDNode *N, DAGCombinerInfo &DCI) const;
1249     SDValue DAGCombineBuildVector(SDNode *N, DAGCombinerInfo &DCI) const;
1250     SDValue DAGCombineTruncBoolExt(SDNode *N, DAGCombinerInfo &DCI) const;
1251     SDValue combineStoreFPToInt(SDNode *N, DAGCombinerInfo &DCI) const;
1252     SDValue combineFPToIntToFP(SDNode *N, DAGCombinerInfo &DCI) const;
1253     SDValue combineSHL(SDNode *N, DAGCombinerInfo &DCI) const;
1254     SDValue combineSRA(SDNode *N, DAGCombinerInfo &DCI) const;
1255     SDValue combineSRL(SDNode *N, DAGCombinerInfo &DCI) const;
1256     SDValue combineMUL(SDNode *N, DAGCombinerInfo &DCI) const;
1257     SDValue combineADD(SDNode *N, DAGCombinerInfo &DCI) const;
1258     SDValue combineFMALike(SDNode *N, DAGCombinerInfo &DCI) const;
1259     SDValue combineTRUNCATE(SDNode *N, DAGCombinerInfo &DCI) const;
1260     SDValue combineSetCC(SDNode *N, DAGCombinerInfo &DCI) const;
1261     SDValue combineABS(SDNode *N, DAGCombinerInfo &DCI) const;
1262     SDValue combineVSelect(SDNode *N, DAGCombinerInfo &DCI) const;
1263     SDValue combineVectorShuffle(ShuffleVectorSDNode *SVN,
1264                                  SelectionDAG &DAG) const;
1265     SDValue combineVReverseMemOP(ShuffleVectorSDNode *SVN, LSBaseSDNode *LSBase,
1266                                  DAGCombinerInfo &DCI) const;
1267 
1268     /// ConvertSETCCToSubtract - looks at SETCC that compares ints. It replaces
1269     /// SETCC with integer subtraction when (1) there is a legal way of doing it
1270     /// (2) keeping the result of comparison in GPR has performance benefit.
1271     SDValue ConvertSETCCToSubtract(SDNode *N, DAGCombinerInfo &DCI) const;
1272 
1273     SDValue getSqrtEstimate(SDValue Operand, SelectionDAG &DAG, int Enabled,
1274                             int &RefinementSteps, bool &UseOneConstNR,
1275                             bool Reciprocal) const override;
1276     SDValue getRecipEstimate(SDValue Operand, SelectionDAG &DAG, int Enabled,
1277                              int &RefinementSteps) const override;
1278     SDValue getSqrtInputTest(SDValue Operand, SelectionDAG &DAG,
1279                              const DenormalMode &Mode) const override;
1280     SDValue getSqrtResultForDenormInput(SDValue Operand,
1281                                         SelectionDAG &DAG) const override;
1282     unsigned combineRepeatedFPDivisors() const override;
1283 
1284     SDValue
1285     combineElementTruncationToVectorTruncation(SDNode *N,
1286                                                DAGCombinerInfo &DCI) const;
1287 
1288     /// lowerToVINSERTH - Return the SDValue if this VECTOR_SHUFFLE can be
1289     /// handled by the VINSERTH instruction introduced in ISA 3.0. This is
1290     /// essentially any shuffle of v8i16 vectors that just inserts one element
1291     /// from one vector into the other.
1292     SDValue lowerToVINSERTH(ShuffleVectorSDNode *N, SelectionDAG &DAG) const;
1293 
1294     /// lowerToVINSERTB - Return the SDValue if this VECTOR_SHUFFLE can be
1295     /// handled by the VINSERTB instruction introduced in ISA 3.0. This is
1296     /// essentially v16i8 vector version of VINSERTH.
1297     SDValue lowerToVINSERTB(ShuffleVectorSDNode *N, SelectionDAG &DAG) const;
1298 
1299     /// lowerToXXSPLTI32DX - Return the SDValue if this VECTOR_SHUFFLE can be
1300     /// handled by the XXSPLTI32DX instruction introduced in ISA 3.1.
1301     SDValue lowerToXXSPLTI32DX(ShuffleVectorSDNode *N, SelectionDAG &DAG) const;
1302 
1303     // Return whether the call instruction can potentially be optimized to a
1304     // tail call. This will cause the optimizers to attempt to move, or
1305     // duplicate return instructions to help enable tail call optimizations.
1306     bool mayBeEmittedAsTailCall(const CallInst *CI) const override;
1307     bool hasBitPreservingFPLogic(EVT VT) const override;
1308     bool isMaskAndCmp0FoldingBeneficial(const Instruction &AndI) const override;
1309   }; // end class PPCTargetLowering
1310 
1311   namespace PPC {
1312 
1313     FastISel *createFastISel(FunctionLoweringInfo &FuncInfo,
1314                              const TargetLibraryInfo *LibInfo);
1315 
1316   } // end namespace PPC
1317 
1318   bool isIntS16Immediate(SDNode *N, int16_t &Imm);
1319   bool isIntS16Immediate(SDValue Op, int16_t &Imm);
1320   bool isIntS34Immediate(SDNode *N, int64_t &Imm);
1321   bool isIntS34Immediate(SDValue Op, int64_t &Imm);
1322 
1323   bool convertToNonDenormSingle(APInt &ArgAPInt);
1324   bool convertToNonDenormSingle(APFloat &ArgAPFloat);
1325 
1326 } // end namespace llvm
1327 
1328 #endif // LLVM_TARGET_POWERPC_PPC32ISELLOWERING_H
1329