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      1 //===- README_P9.txt - Notes for improving Power9 code gen ----------------===//
      2 
      3 TODO: Instructions Need Implement Instrinstics or Map to LLVM IR
      4 
      5 Altivec:
      6 - Vector Compare Not Equal (Zero):
      7   vcmpneb(.) vcmpneh(.) vcmpnew(.)
      8   vcmpnezb(.) vcmpnezh(.) vcmpnezw(.)
      9   . Same as other VCMP*, use VCMP/VCMPo form (support intrinsic)
     10 
     11 - Vector Extract Unsigned: vextractub vextractuh vextractuw vextractd
     12   . Don't use llvm extractelement because they have different semantics
     13   . Use instrinstics:
     14     (set v2i64:$vD, (int_ppc_altivec_vextractub v16i8:$vA, imm:$UIMM))
     15     (set v2i64:$vD, (int_ppc_altivec_vextractuh v8i16:$vA, imm:$UIMM))
     16     (set v2i64:$vD, (int_ppc_altivec_vextractuw v4i32:$vA, imm:$UIMM))
     17     (set v2i64:$vD, (int_ppc_altivec_vextractd  v2i64:$vA, imm:$UIMM))
     18 
     19 - Vector Extract Unsigned Byte Left/Right-Indexed:
     20   vextublx vextubrx vextuhlx vextuhrx vextuwlx vextuwrx
     21   . Use instrinstics:
     22     // Left-Indexed
     23     (set i64:$rD, (int_ppc_altivec_vextublx i64:$rA, v16i8:$vB))
     24     (set i64:$rD, (int_ppc_altivec_vextuhlx i64:$rA, v8i16:$vB))
     25     (set i64:$rD, (int_ppc_altivec_vextuwlx i64:$rA, v4i32:$vB))
     26 
     27     // Right-Indexed
     28     (set i64:$rD, (int_ppc_altivec_vextubrx i64:$rA, v16i8:$vB))
     29     (set i64:$rD, (int_ppc_altivec_vextuhrx i64:$rA, v8i16:$vB))
     30     (set i64:$rD, (int_ppc_altivec_vextuwrx i64:$rA, v4i32:$vB))
     31 
     32 - Vector Insert Element Instructions: vinsertb vinsertd vinserth vinsertw
     33     (set v16i8:$vD, (int_ppc_altivec_vinsertb v16i8:$vA, imm:$UIMM))
     34     (set v8i16:$vD, (int_ppc_altivec_vinsertd v8i16:$vA, imm:$UIMM))
     35     (set v4i32:$vD, (int_ppc_altivec_vinserth v4i32:$vA, imm:$UIMM))
     36     (set v2i64:$vD, (int_ppc_altivec_vinsertw v2i64:$vA, imm:$UIMM))
     37 
     38 - Vector Count Leading/Trailing Zero LSB. Result is placed into GPR[rD]:
     39   vclzlsbb vctzlsbb
     40   . Use intrinsic:
     41     (set i64:$rD, (int_ppc_altivec_vclzlsbb v16i8:$vB))
     42     (set i64:$rD, (int_ppc_altivec_vctzlsbb v16i8:$vB))
     43 
     44 - Vector Count Trailing Zeros: vctzb vctzh vctzw vctzd
     45   . Map to llvm cttz
     46     (set v16i8:$vD, (cttz v16i8:$vB))     // vctzb
     47     (set v8i16:$vD, (cttz v8i16:$vB))     // vctzh
     48     (set v4i32:$vD, (cttz v4i32:$vB))     // vctzw
     49     (set v2i64:$vD, (cttz v2i64:$vB))     // vctzd
     50 
     51 - Vector Extend Sign: vextsb2w vextsh2w vextsb2d vextsh2d vextsw2d
     52   . vextsb2w:
     53     (set v4i32:$vD, (sext v4i8:$vB))
     54 
     55     // PowerISA_V3.0:
     56     do i = 0 to 3
     57        VR[VRT].word[i]  EXTS32(VR[VRB].word[i].byte[3])
     58     end
     59 
     60   . vextsh2w:
     61     (set v4i32:$vD, (sext v4i16:$vB))
     62 
     63     // PowerISA_V3.0:
     64     do i = 0 to 3
     65        VR[VRT].word[i]  EXTS32(VR[VRB].word[i].hword[1])
     66     end
     67 
     68   . vextsb2d
     69     (set v2i64:$vD, (sext v2i8:$vB))
     70 
     71     // PowerISA_V3.0:
     72     do i = 0 to 1
     73        VR[VRT].dword[i]  EXTS64(VR[VRB].dword[i].byte[7])
     74     end
     75 
     76   . vextsh2d
     77     (set v2i64:$vD, (sext v2i16:$vB))
     78 
     79     // PowerISA_V3.0:
     80     do i = 0 to 1
     81        VR[VRT].dword[i]  EXTS64(VR[VRB].dword[i].hword[3])
     82     end
     83 
     84   . vextsw2d
     85     (set v2i64:$vD, (sext v2i32:$vB))
     86 
     87     // PowerISA_V3.0:
     88     do i = 0 to 1
     89        VR[VRT].dword[i]  EXTS64(VR[VRB].dword[i].word[1])
     90     end
     91 
     92 - Vector Integer Negate: vnegw vnegd
     93   . Map to llvm ineg
     94     (set v4i32:$rT, (ineg v4i32:$rA))       // vnegw
     95     (set v2i64:$rT, (ineg v2i64:$rA))       // vnegd
     96 
     97 - Vector Parity Byte: vprtybw vprtybd vprtybq
     98   . Use intrinsic:
     99     (set v4i32:$rD, (int_ppc_altivec_vprtybw v4i32:$vB))
    100     (set v2i64:$rD, (int_ppc_altivec_vprtybd v2i64:$vB))
    101     (set v1i128:$rD, (int_ppc_altivec_vprtybq v1i128:$vB))
    102 
    103 - Vector (Bit) Permute (Right-indexed):
    104   . vbpermd: Same as "vbpermq", use VX1_Int_Ty2:
    105     VX1_Int_Ty2<1484, "vbpermd", int_ppc_altivec_vbpermd, v2i64, v2i64>;
    106 
    107   . vpermr: use VA1a_Int_Ty3
    108     VA1a_Int_Ty3<59, "vpermr", int_ppc_altivec_vpermr, v16i8, v16i8, v16i8>;
    109 
    110 - Vector Rotate Left Mask/Mask-Insert: vrlwnm vrlwmi vrldnm vrldmi
    111   . Use intrinsic:
    112     VX1_Int_Ty<389, "vrlwnm", int_ppc_altivec_vrlwnm, v4i32>;
    113     VX1_Int_Ty<133, "vrlwmi", int_ppc_altivec_vrlwmi, v4i32>;
    114     VX1_Int_Ty<453, "vrldnm", int_ppc_altivec_vrldnm, v2i64>;
    115     VX1_Int_Ty<197, "vrldmi", int_ppc_altivec_vrldmi, v2i64>;
    116 
    117 - Vector Shift Left/Right: vslv vsrv
    118   . Use intrinsic, don't map to llvm shl and lshr, because they have different
    119     semantics, e.g. vslv:
    120 
    121       do i = 0 to 15
    122          sh  VR[VRB].byte[i].bit[5:7]
    123          VR[VRT].byte[i]  src.byte[i:i+1].bit[sh:sh+7]
    124       end
    125 
    126     VR[VRT].byte[i] is composed of 2 bytes from src.byte[i:i+1]
    127 
    128   . VX1_Int_Ty<1860, "vslv", int_ppc_altivec_vslv, v16i8>;
    129     VX1_Int_Ty<1796, "vsrv", int_ppc_altivec_vsrv, v16i8>;
    130 
    131 - Vector Multiply-by-10 (& Write Carry) Unsigned Quadword:
    132   vmul10uq vmul10cuq
    133   . Use intrinsic:
    134     VX1_Int_Ty<513, "vmul10uq",   int_ppc_altivec_vmul10uq,  v1i128>;
    135     VX1_Int_Ty<  1, "vmul10cuq",  int_ppc_altivec_vmul10cuq, v1i128>;
    136 
    137 - Vector Multiply-by-10 Extended (& Write Carry) Unsigned Quadword:
    138   vmul10euq vmul10ecuq
    139   . Use intrinsic:
    140     VX1_Int_Ty<577, "vmul10euq",  int_ppc_altivec_vmul10euq, v1i128>;
    141     VX1_Int_Ty< 65, "vmul10ecuq", int_ppc_altivec_vmul10ecuq, v1i128>;
    142 
    143 - Decimal Convert From/to National/Zoned/Signed-QWord:
    144   bcdcfn. bcdcfz. bcdctn. bcdctz. bcdcfsq. bcdctsq.
    145   . Use instrinstics:
    146     (set v1i128:$vD, (int_ppc_altivec_bcdcfno  v1i128:$vB, i1:$PS))
    147     (set v1i128:$vD, (int_ppc_altivec_bcdcfzo  v1i128:$vB, i1:$PS))
    148     (set v1i128:$vD, (int_ppc_altivec_bcdctno  v1i128:$vB))
    149     (set v1i128:$vD, (int_ppc_altivec_bcdctzo  v1i128:$vB, i1:$PS))
    150     (set v1i128:$vD, (int_ppc_altivec_bcdcfsqo v1i128:$vB, i1:$PS))
    151     (set v1i128:$vD, (int_ppc_altivec_bcdctsqo v1i128:$vB))
    152 
    153 - Decimal Copy-Sign/Set-Sign: bcdcpsgn. bcdsetsgn.
    154   . Use instrinstics:
    155     (set v1i128:$vD, (int_ppc_altivec_bcdcpsgno v1i128:$vA, v1i128:$vB))
    156     (set v1i128:$vD, (int_ppc_altivec_bcdsetsgno v1i128:$vB, i1:$PS))
    157 
    158 - Decimal Shift/Unsigned-Shift/Shift-and-Round: bcds. bcdus. bcdsr.
    159   . Use instrinstics:
    160     (set v1i128:$vD, (int_ppc_altivec_bcdso  v1i128:$vA, v1i128:$vB, i1:$PS))
    161     (set v1i128:$vD, (int_ppc_altivec_bcduso v1i128:$vA, v1i128:$vB))
    162     (set v1i128:$vD, (int_ppc_altivec_bcdsro v1i128:$vA, v1i128:$vB, i1:$PS))
    163 
    164   . Note! Their VA is accessed only 1 byte, i.e. VA.byte[7]
    165 
    166 - Decimal (Unsigned) Truncate: bcdtrunc. bcdutrunc.
    167   . Use instrinstics:
    168     (set v1i128:$vD, (int_ppc_altivec_bcdso  v1i128:$vA, v1i128:$vB, i1:$PS))
    169     (set v1i128:$vD, (int_ppc_altivec_bcduso v1i128:$vA, v1i128:$vB))
    170 
    171   . Note! Their VA is accessed only 2 byte, i.e. VA.hword[3] (VA.bit[48:63])
    172 
    173 VSX:
    174 - QP Copy Sign: xscpsgnqp
    175   . Similar to xscpsgndp
    176   . (set f128:$vT, (fcopysign f128:$vB, f128:$vA)
    177 
    178 - QP Absolute/Negative-Absolute/Negate: xsabsqp xsnabsqp xsnegqp
    179   . Similar to xsabsdp/xsnabsdp/xsnegdp
    180   . (set f128:$vT, (fabs f128:$vB))             // xsabsqp
    181     (set f128:$vT, (fneg (fabs f128:$vB)))      // xsnabsqp
    182     (set f128:$vT, (fneg f128:$vB))             // xsnegqp
    183 
    184 - QP Add/Divide/Multiply/Subtract/Square-Root:
    185   xsaddqp xsdivqp xsmulqp xssubqp xssqrtqp
    186   . Similar to xsadddp
    187   . isCommutable = 1
    188     (set f128:$vT, (fadd f128:$vA, f128:$vB))   // xsaddqp
    189     (set f128:$vT, (fmul f128:$vA, f128:$vB))   // xsmulqp
    190 
    191   . isCommutable = 0
    192     (set f128:$vT, (fdiv f128:$vA, f128:$vB))   // xsdivqp
    193     (set f128:$vT, (fsub f128:$vA, f128:$vB))   // xssubqp
    194     (set f128:$vT, (fsqrt f128:$vB)))           // xssqrtqp
    195 
    196 - Round to Odd of QP Add/Divide/Multiply/Subtract/Square-Root:
    197   xsaddqpo xsdivqpo xsmulqpo xssubqpo xssqrtqpo
    198   . Similar to xsrsqrtedp??
    199       def XSRSQRTEDP : XX2Form<60, 74,
    200                                (outs vsfrc:$XT), (ins vsfrc:$XB),
    201                                "xsrsqrtedp $XT, $XB", IIC_VecFP,
    202                                [(set f64:$XT, (PPCfrsqrte f64:$XB))]>;
    203 
    204   . Define DAG Node in PPCInstrInfo.td:
    205     def PPCfaddrto: SDNode<"PPCISD::FADDRTO", SDTFPBinOp, []>;
    206     def PPCfdivrto: SDNode<"PPCISD::FDIVRTO", SDTFPBinOp, []>;
    207     def PPCfmulrto: SDNode<"PPCISD::FMULRTO", SDTFPBinOp, []>;
    208     def PPCfsubrto: SDNode<"PPCISD::FSUBRTO", SDTFPBinOp, []>;
    209     def PPCfsqrtrto: SDNode<"PPCISD::FSQRTRTO", SDTFPUnaryOp, []>;
    210 
    211     DAG patterns of each instruction (PPCInstrVSX.td):
    212     . isCommutable = 1
    213       (set f128:$vT, (PPCfaddrto f128:$vA, f128:$vB))   // xsaddqpo
    214       (set f128:$vT, (PPCfmulrto f128:$vA, f128:$vB))   // xsmulqpo
    215 
    216     . isCommutable = 0
    217       (set f128:$vT, (PPCfdivrto f128:$vA, f128:$vB))   // xsdivqpo
    218       (set f128:$vT, (PPCfsubrto f128:$vA, f128:$vB))   // xssubqpo
    219       (set f128:$vT, (PPCfsqrtrto f128:$vB))            // xssqrtqpo
    220 
    221 - QP (Negative) Multiply-{Add/Subtract}: xsmaddqp xsmsubqp xsnmaddqp xsnmsubqp
    222   . Ref: xsmaddadp/xsmsubadp/xsnmaddadp/xsnmsubadp
    223 
    224   . isCommutable = 1
    225     // xsmaddqp
    226     [(set f128:$vT, (fma f128:$vA, f128:$vB, f128:$vTi))]>,
    227     RegConstraint<"$vTi = $vT">, NoEncode<"$vTi">,
    228     AltVSXFMARel;
    229 
    230     // xsmsubqp
    231     [(set f128:$vT, (fma f128:$vA, f128:$vB, (fneg f128:$vTi)))]>,
    232     RegConstraint<"$vTi = $vT">, NoEncode<"$vTi">,
    233     AltVSXFMARel;
    234 
    235     // xsnmaddqp
    236     [(set f128:$vT, (fneg (fma f128:$vA, f128:$vB, f128:$vTi)))]>,
    237     RegConstraint<"$vTi = $vT">, NoEncode<"$vTi">,
    238     AltVSXFMARel;
    239 
    240     // xsnmsubqp
    241     [(set f128:$vT, (fneg (fma f128:$vA, f128:$vB, (fneg f128:$vTi))))]>,
    242     RegConstraint<"$vTi = $vT">, NoEncode<"$vTi">,
    243     AltVSXFMARel;
    244 
    245 - Round to Odd of QP (Negative) Multiply-{Add/Subtract}:
    246   xsmaddqpo xsmsubqpo xsnmaddqpo xsnmsubqpo
    247   . Similar to xsrsqrtedp??
    248 
    249   . Define DAG Node in PPCInstrInfo.td:
    250     def PPCfmarto: SDNode<"PPCISD::FMARTO", SDTFPTernaryOp, []>;
    251 
    252     It looks like we only need to define "PPCfmarto" for these instructions,
    253     because according to PowerISA_V3.0, these instructions perform RTO on
    254     fma's result:
    255         xsmaddqp(o)
    256         v       bfp_MULTIPLY_ADD(src1, src3, src2)
    257         rnd     bfp_ROUND_TO_BFP128(RO, FPSCR.RN, v)
    258         result  bfp_CONVERT_TO_BFP128(rnd)
    259 
    260         xsmsubqp(o)
    261         v       bfp_MULTIPLY_ADD(src1, src3, bfp_NEGATE(src2))
    262         rnd     bfp_ROUND_TO_BFP128(RO, FPSCR.RN, v)
    263         result  bfp_CONVERT_TO_BFP128(rnd)
    264 
    265         xsnmaddqp(o)
    266         v       bfp_MULTIPLY_ADD(src1,src3,src2)
    267         rnd     bfp_NEGATE(bfp_ROUND_TO_BFP128(RO, FPSCR.RN, v))
    268         result  bfp_CONVERT_TO_BFP128(rnd)
    269 
    270         xsnmsubqp(o)
    271         v       bfp_MULTIPLY_ADD(src1, src3, bfp_NEGATE(src2))
    272         rnd     bfp_NEGATE(bfp_ROUND_TO_BFP128(RO, FPSCR.RN, v))
    273         result  bfp_CONVERT_TO_BFP128(rnd)
    274 
    275     DAG patterns of each instruction (PPCInstrVSX.td):
    276     . isCommutable = 1
    277       // xsmaddqpo
    278       [(set f128:$vT, (PPCfmarto f128:$vA, f128:$vB, f128:$vTi))]>,
    279       RegConstraint<"$vTi = $vT">, NoEncode<"$vTi">,
    280       AltVSXFMARel;
    281 
    282       // xsmsubqpo
    283       [(set f128:$vT, (PPCfmarto f128:$vA, f128:$vB, (fneg f128:$vTi)))]>,
    284       RegConstraint<"$vTi = $vT">, NoEncode<"$vTi">,
    285       AltVSXFMARel;
    286 
    287       // xsnmaddqpo
    288       [(set f128:$vT, (fneg (PPCfmarto f128:$vA, f128:$vB, f128:$vTi)))]>,
    289       RegConstraint<"$vTi = $vT">, NoEncode<"$vTi">,
    290       AltVSXFMARel;
    291 
    292       // xsnmsubqpo
    293       [(set f128:$vT, (fneg (PPCfmarto f128:$vA, f128:$vB, (fneg f128:$vTi))))]>,
    294       RegConstraint<"$vTi = $vT">, NoEncode<"$vTi">,
    295       AltVSXFMARel;
    296 
    297 - QP Compare Ordered/Unordered: xscmpoqp xscmpuqp
    298   . ref: XSCMPUDP
    299       def XSCMPUDP : XX3Form_1<60, 35,
    300                                (outs crrc:$crD), (ins vsfrc:$XA, vsfrc:$XB),
    301                                "xscmpudp $crD, $XA, $XB", IIC_FPCompare, []>;
    302 
    303   . No SDAG, intrinsic, builtin are required??
    304     Or llvm fcmp order/unorder compare??
    305 
    306 - DP/QP Compare Exponents: xscmpexpdp xscmpexpqp
    307   . No SDAG, intrinsic, builtin are required?
    308 
    309 - DP Compare ==, >=, >, !=: xscmpeqdp xscmpgedp xscmpgtdp xscmpnedp
    310   . I checked existing instruction "XSCMPUDP". They are different in target
    311     register. "XSCMPUDP" write to CR field, xscmp*dp write to VSX register
    312 
    313   . Use instrinsic:
    314     (set i128:$XT, (int_ppc_vsx_xscmpeqdp f64:$XA, f64:$XB))
    315     (set i128:$XT, (int_ppc_vsx_xscmpgedp f64:$XA, f64:$XB))
    316     (set i128:$XT, (int_ppc_vsx_xscmpgtdp f64:$XA, f64:$XB))
    317     (set i128:$XT, (int_ppc_vsx_xscmpnedp f64:$XA, f64:$XB))
    318 
    319 - Vector Compare Not Equal: xvcmpnedp xvcmpnedp. xvcmpnesp xvcmpnesp.
    320   . Similar to xvcmpeqdp:
    321       defm XVCMPEQDP : XX3Form_Rcr<60, 99,
    322                                  "xvcmpeqdp", "$XT, $XA, $XB", IIC_VecFPCompare,
    323                                  int_ppc_vsx_xvcmpeqdp, v2i64, v2f64>;
    324 
    325   . So we should use "XX3Form_Rcr" to implement instrinsic
    326 
    327 - Convert DP -> QP: xscvdpqp
    328   . Similar to XSCVDPSP:
    329       def XSCVDPSP : XX2Form<60, 265,
    330                           (outs vsfrc:$XT), (ins vsfrc:$XB),
    331                           "xscvdpsp $XT, $XB", IIC_VecFP, []>;
    332   . So, No SDAG, intrinsic, builtin are required??
    333 
    334 - Round & Convert QP -> DP (dword[1] is set to zero): xscvqpdp xscvqpdpo
    335   . Similar to XSCVDPSP
    336   . No SDAG, intrinsic, builtin are required??
    337 
    338 - Truncate & Convert QP -> (Un)Signed (D)Word (dword[1] is set to zero):
    339   xscvqpsdz xscvqpswz xscvqpudz xscvqpuwz
    340   . According to PowerISA_V3.0, these are similar to "XSCVDPSXDS", "XSCVDPSXWS",
    341     "XSCVDPUXDS", "XSCVDPUXWS"
    342 
    343   . DAG patterns:
    344     (set f128:$XT, (PPCfctidz f128:$XB))    // xscvqpsdz
    345     (set f128:$XT, (PPCfctiwz f128:$XB))    // xscvqpswz
    346     (set f128:$XT, (PPCfctiduz f128:$XB))   // xscvqpudz
    347     (set f128:$XT, (PPCfctiwuz f128:$XB))   // xscvqpuwz
    348 
    349 - Convert (Un)Signed DWord -> QP: xscvsdqp xscvudqp
    350   . Similar to XSCVSXDSP
    351   . (set f128:$XT, (PPCfcfids f64:$XB))     // xscvsdqp
    352     (set f128:$XT, (PPCfcfidus f64:$XB))    // xscvudqp
    353 
    354 - (Round &) Convert DP <-> HP: xscvdphp xscvhpdp
    355   . Similar to XSCVDPSP
    356   . No SDAG, intrinsic, builtin are required??
    357 
    358 - Vector HP -> SP: xvcvhpsp xvcvsphp
    359   . Similar to XVCVDPSP:
    360       def XVCVDPSP : XX2Form<60, 393,
    361                           (outs vsrc:$XT), (ins vsrc:$XB),
    362                           "xvcvdpsp $XT, $XB", IIC_VecFP, []>;
    363   . No SDAG, intrinsic, builtin are required??
    364 
    365 - Round to Quad-Precision Integer: xsrqpi xsrqpix
    366   . These are combination of "XSRDPI", "XSRDPIC", "XSRDPIM", .., because you
    367     need to assign rounding mode in instruction
    368   . Provide builtin?
    369     (set f128:$vT, (int_ppc_vsx_xsrqpi f128:$vB))
    370     (set f128:$vT, (int_ppc_vsx_xsrqpix f128:$vB))
    371 
    372 - Round Quad-Precision to Double-Extended Precision (fp80): xsrqpxp
    373   . Provide builtin?
    374     (set f128:$vT, (int_ppc_vsx_xsrqpxp f128:$vB))
    375 
    376 Fixed Point Facility:
    377 
    378 - Exploit cmprb and cmpeqb (perhaps for something like
    379   isalpha/isdigit/isupper/islower and isspace respectivelly). This can
    380   perhaps be done through a builtin.
    381 
    382 - Provide testing for cnttz[dw]
    383 - Insert Exponent DP/QP: xsiexpdp xsiexpqp
    384   . Use intrinsic?
    385   . xsiexpdp:
    386     // Note: rA and rB are the unsigned integer value.
    387     (set f128:$XT, (int_ppc_vsx_xsiexpdp i64:$rA, i64:$rB))
    388 
    389   . xsiexpqp:
    390     (set f128:$vT, (int_ppc_vsx_xsiexpqp f128:$vA, f64:$vB))
    391 
    392 - Extract Exponent/Significand DP/QP: xsxexpdp xsxsigdp xsxexpqp xsxsigqp
    393   . Use intrinsic?
    394   . (set i64:$rT, (int_ppc_vsx_xsxexpdp f64$XB))    // xsxexpdp
    395     (set i64:$rT, (int_ppc_vsx_xsxsigdp f64$XB))    // xsxsigdp
    396     (set f128:$vT, (int_ppc_vsx_xsxexpqp f128$vB))  // xsxexpqp
    397     (set f128:$vT, (int_ppc_vsx_xsxsigqp f128$vB))  // xsxsigqp
    398 
    399 - Vector Insert Word: xxinsertw
    400   - Useful for inserting f32/i32 elements into vectors (the element to be
    401     inserted needs to be prepared)
    402   . Note: llvm has insertelem in "Vector Operations"
    403     ; yields <n x <ty>>
    404     <result> = insertelement <n x <ty>> <val>, <ty> <elt>, <ty2> <idx>
    405 
    406     But how to map to it??
    407     [(set v1f128:$XT, (insertelement v1f128:$XTi, f128:$XB, i4:$UIMM))]>,
    408     RegConstraint<"$XTi = $XT">, NoEncode<"$XTi">,
    409 
    410   . Or use intrinsic?
    411     (set v1f128:$XT, (int_ppc_vsx_xxinsertw v1f128:$XTi, f128:$XB, i4:$UIMM))
    412 
    413 - Vector Extract Unsigned Word: xxextractuw
    414   - Not useful for extraction of f32 from v4f32 (the current pattern is better -
    415     shift->convert)
    416   - It is useful for (uint_to_fp (vector_extract v4i32, N))
    417   - Unfortunately, it can't be used for (sint_to_fp (vector_extract v4i32, N))
    418   . Note: llvm has extractelement in "Vector Operations"
    419     ; yields <ty>
    420     <result> = extractelement <n x <ty>> <val>, <ty2> <idx>
    421 
    422     How to map to it??
    423     [(set f128:$XT, (extractelement v1f128:$XB, i4:$UIMM))]
    424 
    425   . Or use intrinsic?
    426     (set f128:$XT, (int_ppc_vsx_xxextractuw v1f128:$XB, i4:$UIMM))
    427 
    428 - Vector Insert Exponent DP/SP: xviexpdp xviexpsp
    429   . Use intrinsic
    430     (set v2f64:$XT, (int_ppc_vsx_xviexpdp v2f64:$XA, v2f64:$XB))
    431     (set v4f32:$XT, (int_ppc_vsx_xviexpsp v4f32:$XA, v4f32:$XB))
    432 
    433 - Vector Extract Exponent/Significand DP/SP: xvxexpdp xvxexpsp xvxsigdp xvxsigsp
    434   . Use intrinsic
    435     (set v2f64:$XT, (int_ppc_vsx_xvxexpdp v2f64:$XB))
    436     (set v4f32:$XT, (int_ppc_vsx_xvxexpsp v4f32:$XB))
    437     (set v2f64:$XT, (int_ppc_vsx_xvxsigdp v2f64:$XB))
    438     (set v4f32:$XT, (int_ppc_vsx_xvxsigsp v4f32:$XB))
    439 
    440 - Test Data Class SP/DP/QP: xststdcsp xststdcdp xststdcqp
    441   . No SDAG, intrinsic, builtin are required?
    442     Because it seems that we have no way to map BF field?
    443 
    444     Instruction Form: [PO T XO B XO BX TX]
    445     Asm: xststd* BF,XB,DCMX
    446 
    447     BF is an index to CR register field.
    448 
    449 - Vector Test Data Class SP/DP: xvtstdcsp xvtstdcdp
    450   . Use intrinsic
    451     (set v4f32:$XT, (int_ppc_vsx_xvtstdcsp v4f32:$XB, i7:$DCMX))
    452     (set v2f64:$XT, (int_ppc_vsx_xvtstdcdp v2f64:$XB, i7:$DCMX))
    453 
    454 - Maximum/Minimum Type-C/Type-J DP: xsmaxcdp xsmaxjdp xsmincdp xsminjdp
    455   . PowerISA_V3.0:
    456     "xsmaxcdp can be used to implement the C/C++/Java conditional operation
    457      (x>y)?x:y for single-precision and double-precision arguments."
    458 
    459     Note! c type and j type have different behavior when:
    460     1. Either input is NaN
    461     2. Both input are +-Infinity, +-Zero
    462 
    463   . dtype map to llvm fmaxnum/fminnum
    464     jtype use intrinsic
    465 
    466   . xsmaxcdp xsmincdp
    467     (set f64:$XT, (fmaxnum f64:$XA, f64:$XB))
    468     (set f64:$XT, (fminnum f64:$XA, f64:$XB))
    469 
    470   . xsmaxjdp xsminjdp
    471     (set f64:$XT, (int_ppc_vsx_xsmaxjdp f64:$XA, f64:$XB))
    472     (set f64:$XT, (int_ppc_vsx_xsminjdp f64:$XA, f64:$XB))
    473 
    474 - Vector Byte-Reverse H/W/D/Q Word: xxbrh xxbrw xxbrd xxbrq
    475   . Use intrinsic
    476     (set v8i16:$XT, (int_ppc_vsx_xxbrh v8i16:$XB))
    477     (set v4i32:$XT, (int_ppc_vsx_xxbrw v4i32:$XB))
    478     (set v2i64:$XT, (int_ppc_vsx_xxbrd v2i64:$XB))
    479     (set v1i128:$XT, (int_ppc_vsx_xxbrq v1i128:$XB))
    480 
    481 - Vector Permute: xxperm xxpermr
    482   . I have checked "PPCxxswapd" in PPCInstrVSX.td, but they are different
    483   . Use intrinsic
    484     (set v16i8:$XT, (int_ppc_vsx_xxperm v16i8:$XA, v16i8:$XB))
    485     (set v16i8:$XT, (int_ppc_vsx_xxpermr v16i8:$XA, v16i8:$XB))
    486 
    487 - Vector Splat Immediate Byte: xxspltib
    488   . Similar to XXSPLTW:
    489       def XXSPLTW : XX2Form_2<60, 164,
    490                            (outs vsrc:$XT), (ins vsrc:$XB, u2imm:$UIM),
    491                            "xxspltw $XT, $XB, $UIM", IIC_VecPerm, []>;
    492 
    493   . No SDAG, intrinsic, builtin are required?
    494 
    495 - Load/Store Vector: lxv stxv
    496   . Has likely SDAG match:
    497     (set v?:$XT, (load ix16addr:$src))
    498     (set v?:$XT, (store ix16addr:$dst))
    499 
    500   . Need define ix16addr in PPCInstrInfo.td
    501     ix16addr: 16-byte aligned, see "def memrix16" in PPCInstrInfo.td
    502 
    503 - Load/Store Vector Indexed: lxvx stxvx
    504   . Has likely SDAG match:
    505     (set v?:$XT, (load xoaddr:$src))
    506     (set v?:$XT, (store xoaddr:$dst))
    507 
    508 - Load/Store DWord: lxsd stxsd
    509   . Similar to lxsdx/stxsdx:
    510     def LXSDX : XX1Form<31, 588,
    511                         (outs vsfrc:$XT), (ins memrr:$src),
    512                         "lxsdx $XT, $src", IIC_LdStLFD,
    513                         [(set f64:$XT, (load xoaddr:$src))]>;
    514 
    515   . (set f64:$XT, (load ixaddr:$src))
    516     (set f64:$XT, (store ixaddr:$dst))
    517 
    518 - Load/Store SP, with conversion from/to DP: lxssp stxssp
    519   . Similar to lxsspx/stxsspx:
    520     def LXSSPX : XX1Form<31, 524, (outs vssrc:$XT), (ins memrr:$src),
    521                          "lxsspx $XT, $src", IIC_LdStLFD,
    522                          [(set f32:$XT, (load xoaddr:$src))]>;
    523 
    524   . (set f32:$XT, (load ixaddr:$src))
    525     (set f32:$XT, (store ixaddr:$dst))
    526 
    527 - Load as Integer Byte/Halfword & Zero Indexed: lxsibzx lxsihzx
    528   . Similar to lxsiwzx:
    529     def LXSIWZX : XX1Form<31, 12, (outs vsfrc:$XT), (ins memrr:$src),
    530                           "lxsiwzx $XT, $src", IIC_LdStLFD,
    531                           [(set f64:$XT, (PPClfiwzx xoaddr:$src))]>;
    532 
    533   . (set f64:$XT, (PPClfiwzx xoaddr:$src))
    534 
    535 - Store as Integer Byte/Halfword Indexed: stxsibx stxsihx
    536   . Similar to stxsiwx:
    537     def STXSIWX : XX1Form<31, 140, (outs), (ins vsfrc:$XT, memrr:$dst),
    538                           "stxsiwx $XT, $dst", IIC_LdStSTFD,
    539                           [(PPCstfiwx f64:$XT, xoaddr:$dst)]>;
    540 
    541   . (PPCstfiwx f64:$XT, xoaddr:$dst)
    542 
    543 - Load Vector Halfword*8/Byte*16 Indexed: lxvh8x lxvb16x
    544   . Similar to lxvd2x/lxvw4x:
    545     def LXVD2X : XX1Form<31, 844,
    546                          (outs vsrc:$XT), (ins memrr:$src),
    547                          "lxvd2x $XT, $src", IIC_LdStLFD,
    548                          [(set v2f64:$XT, (int_ppc_vsx_lxvd2x xoaddr:$src))]>;
    549 
    550   . (set v8i16:$XT, (int_ppc_vsx_lxvh8x xoaddr:$src))
    551     (set v16i8:$XT, (int_ppc_vsx_lxvb16x xoaddr:$src))
    552 
    553 - Store Vector Halfword*8/Byte*16 Indexed: stxvh8x stxvb16x
    554   . Similar to stxvd2x/stxvw4x:
    555     def STXVD2X : XX1Form<31, 972,
    556                          (outs), (ins vsrc:$XT, memrr:$dst),
    557                          "stxvd2x $XT, $dst", IIC_LdStSTFD,
    558                          [(store v2f64:$XT, xoaddr:$dst)]>;
    559 
    560   . (store v8i16:$XT, xoaddr:$dst)
    561     (store v16i8:$XT, xoaddr:$dst)
    562 
    563 - Load/Store Vector (Left-justified) with Length: lxvl lxvll stxvl stxvll
    564   . Likely needs an intrinsic
    565   . (set v?:$XT, (int_ppc_vsx_lxvl xoaddr:$src))
    566     (set v?:$XT, (int_ppc_vsx_lxvll xoaddr:$src))
    567 
    568   . (int_ppc_vsx_stxvl xoaddr:$dst))
    569     (int_ppc_vsx_stxvll xoaddr:$dst))
    570 
    571 - Load Vector Word & Splat Indexed: lxvwsx
    572   . Likely needs an intrinsic
    573   . (set v?:$XT, (int_ppc_vsx_lxvwsx xoaddr:$src))
    574 
    575 Atomic operations (l[dw]at, st[dw]at):
    576 - Provide custom lowering for common atomic operations to use these
    577   instructions with the correct Function Code
    578 - Ensure the operands are in the correct register (i.e. RT+1, RT+2)
    579 - Provide builtins since not all FC's necessarily have an existing LLVM
    580   atomic operation
    581 
    582 Load Doubleword Monitored (ldmx):
    583 - Investigate whether there are any uses for this. It seems to be related to
    584   Garbage Collection so it isn't likely to be all that useful for most
    585   languages we deal with.
    586 
    587 Move to CR from XER Extended (mcrxrx):
    588 - Is there a use for this in LLVM?
    589 
    590 Fixed Point Facility:
    591 
    592 - Copy-Paste Facility: copy copy_first cp_abort paste paste. paste_last
    593   . Use instrinstics:
    594     (int_ppc_copy_first i32:$rA, i32:$rB)
    595     (int_ppc_copy i32:$rA, i32:$rB)
    596 
    597     (int_ppc_paste i32:$rA, i32:$rB)
    598     (int_ppc_paste_last i32:$rA, i32:$rB)
    599 
    600     (int_cp_abort)
    601 
    602 - Message Synchronize: msgsync
    603 - SLB*: slbieg slbsync
    604 - stop
    605   . No instrinstics
    606