// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// GOPPC64 values indicate power8, power9, etc.
// That means the code is compiled for that target,
// and will not run on earlier targets.
//
(Add(Ptr|64|32|16|8) ...) => (ADD ...)
(Add64F ...) => (FADD ...)
(Add32F ...) => (FADDS ...)

(Sub(Ptr|64|32|16|8) ...) => (SUB ...)
(Sub32F ...) => (FSUBS ...)
(Sub64F ...) => (FSUB ...)

// Combine 64 bit integer multiply and adds
(ADD l:(MULLD x y) z) && buildcfg.GOPPC64 >= 9 && l.Uses == 1 && clobber(l) => (MADDLD x y z)

(Mod16 x y) => (Mod32 (SignExt16to32 x) (SignExt16to32 y))
(Mod16u x y) => (Mod32u (ZeroExt16to32 x) (ZeroExt16to32 y))
(Mod8 x y) => (Mod32 (SignExt8to32 x) (SignExt8to32 y))
(Mod8u x y) => (Mod32u (ZeroExt8to32 x) (ZeroExt8to32 y))
(Mod64 x y) && buildcfg.GOPPC64 >=9 => (MODSD x y)
(Mod64 x y) && buildcfg.GOPPC64 <=8 => (SUB x (MULLD y (DIVD x y)))
(Mod64u x y) && buildcfg.GOPPC64 >= 9 => (MODUD x y)
(Mod64u x y) && buildcfg.GOPPC64 <= 8 => (SUB x (MULLD y (DIVDU x y)))
(Mod32 x y) && buildcfg.GOPPC64 >= 9 => (MODSW x y)
(Mod32 x y) && buildcfg.GOPPC64 <= 8 => (SUB x (MULLW y (DIVW x y)))
(Mod32u x y) && buildcfg.GOPPC64 >= 9 => (MODUW x y)
(Mod32u x y) && buildcfg.GOPPC64 <= 8 => (SUB x (MULLW y (DIVWU x y)))

// (x + y) / 2 with x>=y => (x - y) / 2 + y
(Avg64u <t> x y) => (ADD (SRDconst <t> (SUB <t> x y) [1]) y)

(Mul64 ...) => (MULLD ...)
(Mul(32|16|8) ...) => (MULLW ...)
(Select0 (Mul64uhilo x y)) => (MULHDU x y)
(Select1 (Mul64uhilo x y)) => (MULLD x y)

(Div64 [false] x y) => (DIVD x y)
(Div64u ...) => (DIVDU ...)
(Div32 [false] x y) => (DIVW x y)
(Div32u ...) => (DIVWU ...)
(Div16 [false]  x y) => (DIVW  (SignExt16to32 x) (SignExt16to32 y))
(Div16u x y) => (DIVWU (ZeroExt16to32 x) (ZeroExt16to32 y))
(Div8 x y) => (DIVW  (SignExt8to32 x) (SignExt8to32 y))
(Div8u x y) => (DIVWU (ZeroExt8to32 x) (ZeroExt8to32 y))

(Hmul(64|64u|32|32u) ...) => (MULH(D|DU|W|WU) ...)

(Mul(32|64)F ...) => ((FMULS|FMUL) ...)

(Div(32|64)F ...) => ((FDIVS|FDIV) ...)

// Lowering float <=> int
(Cvt32to(32|64)F x) => ((FCFIDS|FCFID) (MTVSRD (SignExt32to64 x)))
(Cvt64to(32|64)F x) => ((FCFIDS|FCFID) (MTVSRD x))

(Cvt32Fto(32|64) x) => (MFVSRD (FCTI(W|D)Z x))
(Cvt64Fto(32|64) x) => (MFVSRD (FCTI(W|D)Z x))

(Cvt32Fto64F ...) => (Copy ...) // Note v will have the wrong type for patterns dependent on Float32/Float64
(Cvt64Fto32F ...) => (FRSP ...)

(CvtBoolToUint8 ...) => (Copy ...)

(Round(32|64)F ...) => (LoweredRound(32|64)F ...)

(Sqrt ...) => (FSQRT ...)
(Sqrt32 ...) => (FSQRTS ...)
(Floor ...) => (FFLOOR ...)
(Ceil ...) => (FCEIL ...)
(Trunc ...) => (FTRUNC ...)
(Round ...) => (FROUND ...)
(Copysign x y) => (FCPSGN y x)
(Abs ...) => (FABS ...)
(FMA ...) => (FMADD ...)

// Lowering extension
// Note: we always extend to 64 bits even though some ops don't need that many result bits.
(SignExt8to(16|32|64) ...) => (MOVBreg ...)
(SignExt16to(32|64) ...) => (MOVHreg ...)
(SignExt32to64 ...) => (MOVWreg ...)

(ZeroExt8to(16|32|64) ...) => (MOVBZreg ...)
(ZeroExt16to(32|64) ...) => (MOVHZreg ...)
(ZeroExt32to64 ...) => (MOVWZreg ...)

(Trunc(16|32|64)to8 <t> x) && t.IsSigned() => (MOVBreg x)
(Trunc(16|32|64)to8  x) => (MOVBZreg x)
(Trunc(32|64)to16 <t> x) && t.IsSigned() => (MOVHreg x)
(Trunc(32|64)to16 x) => (MOVHZreg x)
(Trunc64to32 <t> x) && t.IsSigned() => (MOVWreg x)
(Trunc64to32 x) => (MOVWZreg x)

// Lowering constants
(Const(64|32|16|8) [val]) => (MOVDconst [int64(val)])
(Const(32|64)F ...) => (FMOV(S|D)const ...)
(ConstNil) => (MOVDconst [0])
(ConstBool [t]) => (MOVDconst [b2i(t)])

// Carrying addition.
(Select0 (Add64carry x y c)) =>            (Select0 <typ.UInt64> (ADDE x y (Select1 <typ.UInt64> (ADDCconst c [-1]))))
(Select1 (Add64carry x y c)) => (ADDZEzero (Select1 <typ.UInt64> (ADDE x y (Select1 <typ.UInt64> (ADDCconst c [-1])))))
// Fold initial carry bit if 0.
(ADDE x y (Select1 <typ.UInt64> (ADDCconst (MOVDconst [0]) [-1]))) => (ADDC x y)
// Fold transfer of CA -> GPR -> CA. Note 2 uses when feeding into a chained Add64carry.
(Select1 (ADDCconst n:(ADDZEzero x) [-1])) && n.Uses <= 2 => x

// Borrowing subtraction.
(Select0 (Sub64borrow x y c)) =>                 (Select0 <typ.UInt64> (SUBE x y (Select1 <typ.UInt64> (SUBCconst c [0]))))
(Select1 (Sub64borrow x y c)) => (NEG (SUBZEzero (Select1 <typ.UInt64> (SUBE x y (Select1 <typ.UInt64> (SUBCconst c [0]))))))
// Fold initial borrow bit if 0.
(SUBE x y (Select1 <typ.UInt64> (SUBCconst (MOVDconst [0]) [0]))) => (SUBC x y)
// Fold transfer of CA -> GPR -> CA. Note 2 uses when feeding into a chained Sub64borrow.
(Select1 (SUBCconst n:(NEG (SUBZEzero x)) [0])) && n.Uses <= 2 => x

// Constant folding
(FABS (FMOVDconst [x])) => (FMOVDconst [math.Abs(x)])
(FSQRT (FMOVDconst [x])) && x >= 0 => (FMOVDconst [math.Sqrt(x)])
(FFLOOR (FMOVDconst [x])) => (FMOVDconst [math.Floor(x)])
(FCEIL (FMOVDconst [x])) => (FMOVDconst [math.Ceil(x)])
(FTRUNC (FMOVDconst [x])) => (FMOVDconst [math.Trunc(x)])

// Rotates
(RotateLeft8 <t> x (MOVDconst [c])) => (Or8 (Lsh8x64 <t> x (MOVDconst [c&7])) (Rsh8Ux64 <t> x (MOVDconst [-c&7])))
(RotateLeft16 <t> x (MOVDconst [c])) => (Or16 (Lsh16x64 <t> x (MOVDconst [c&15])) (Rsh16Ux64 <t> x (MOVDconst [-c&15])))
(RotateLeft(32|64) ...) => ((ROTLW|ROTL) ...)

// Constant rotate generation
(ROTLW  x (MOVDconst [c])) => (ROTLWconst  x [c&31])
(ROTL   x (MOVDconst [c])) => (ROTLconst   x [c&63])

// Combine rotate and mask operations
(Select0 (ANDCCconst [m] (ROTLWconst [r] x))) && isPPC64WordRotateMask(m) => (RLWINM [encodePPC64RotateMask(r,m,32)] x)
(AND (MOVDconst [m]) (ROTLWconst [r] x)) && isPPC64WordRotateMask(m) => (RLWINM [encodePPC64RotateMask(r,m,32)] x)
(Select0 (ANDCCconst [m] (ROTLW x r))) && isPPC64WordRotateMask(m) => (RLWNM [encodePPC64RotateMask(0,m,32)] x r)
(AND (MOVDconst [m]) (ROTLW x r)) && isPPC64WordRotateMask(m) => (RLWNM [encodePPC64RotateMask(0,m,32)] x r)

// Note, any rotated word bitmask is still a valid word bitmask.
(ROTLWconst [r] (AND (MOVDconst [m]) x)) && isPPC64WordRotateMask(m) => (RLWINM [encodePPC64RotateMask(r,rotateLeft32(m,r),32)] x)
(ROTLWconst [r] (Select0 (ANDCCconst [m] x))) && isPPC64WordRotateMask(m) => (RLWINM [encodePPC64RotateMask(r,rotateLeft32(m,r),32)] x)

(Select0 (ANDCCconst [m] (SRWconst x [s]))) && mergePPC64RShiftMask(m,s,32) == 0 => (MOVDconst [0])
(Select0 (ANDCCconst [m] (SRWconst x [s]))) && mergePPC64AndSrwi(m,s) != 0 => (RLWINM [mergePPC64AndSrwi(m,s)] x)
(AND (MOVDconst [m]) (SRWconst x [s])) && mergePPC64RShiftMask(m,s,32) == 0 => (MOVDconst [0])
(AND (MOVDconst [m]) (SRWconst x [s])) && mergePPC64AndSrwi(m,s) != 0 => (RLWINM [mergePPC64AndSrwi(m,s)] x)

(SRWconst (Select0 (ANDCCconst [m] x)) [s]) && mergePPC64RShiftMask(m>>uint(s),s,32) == 0 => (MOVDconst [0])
(SRWconst (Select0 (ANDCCconst [m] x)) [s]) && mergePPC64AndSrwi(m>>uint(s),s) != 0 => (RLWINM [mergePPC64AndSrwi(m>>uint(s),s)] x)
(SRWconst (AND (MOVDconst [m]) x) [s]) && mergePPC64RShiftMask(m>>uint(s),s,32) == 0 => (MOVDconst [0])
(SRWconst (AND (MOVDconst [m]) x) [s]) && mergePPC64AndSrwi(m>>uint(s),s) != 0 => (RLWINM [mergePPC64AndSrwi(m>>uint(s),s)] x)

// Merge shift right + shift left and clear left (e.g for a table lookup)
(CLRLSLDI [c] (SRWconst [s] x)) && mergePPC64ClrlsldiSrw(int64(c),s) != 0 => (RLWINM [mergePPC64ClrlsldiSrw(int64(c),s)] x)
(SLDconst [l] (SRWconst [r] x)) && mergePPC64SldiSrw(l,r) != 0 => (RLWINM [mergePPC64SldiSrw(l,r)] x)
// The following reduction shows up frequently too. e.g b[(x>>14)&0xFF]
(CLRLSLDI [c] i:(RLWINM [s] x)) && mergePPC64ClrlsldiRlwinm(c,s) != 0 => (RLWINM [mergePPC64ClrlsldiRlwinm(c,s)] x)

// large constant signed right shift, we leave the sign bit
(Rsh64x64 x (MOVDconst [c])) && uint64(c) >= 64 => (SRADconst x [63])
(Rsh32x64 x (MOVDconst [c])) && uint64(c) >= 32 => (SRAWconst x [63])
(Rsh16x64 x (MOVDconst [c])) && uint64(c) >= 16 => (SRAWconst (SignExt16to32 x) [63])
(Rsh8x64  x (MOVDconst [c])) && uint64(c) >= 8  => (SRAWconst (SignExt8to32  x) [63])

// constant shifts
((Lsh64|Rsh64|Rsh64U)x64  x (MOVDconst [c])) && uint64(c) < 64 => (S(L|RA|R)Dconst x [c])
((Lsh32|Rsh32|Rsh32U)x64  x (MOVDconst [c])) && uint64(c) < 32 => (S(L|RA|R)Wconst x [c])
((Rsh16|Rsh16U)x64  x (MOVDconst [c])) && uint64(c) < 16 => (SR(AW|W)const ((Sign|Zero)Ext16to32 x) [c])
(Lsh16x64  x (MOVDconst [c])) && uint64(c) < 16 => (SLWconst x [c])
((Rsh8|Rsh8U)x64  x (MOVDconst [c])) && uint64(c) < 8 => (SR(AW|W)const ((Sign|Zero)Ext8to32 x) [c])
(Lsh8x64  x (MOVDconst [c])) && uint64(c) < 8 => (SLWconst x [c])

// Lower bounded shifts first. No need to check shift value.
(Lsh64x(64|32|16|8)  x y) && shiftIsBounded(v) => (SLD x y)
(Lsh32x(64|32|16|8)  x y) && shiftIsBounded(v) => (SLW x y)
(Lsh16x(64|32|16|8)  x y) && shiftIsBounded(v) => (SLD x y)
(Lsh8x(64|32|16|8)   x y) && shiftIsBounded(v) => (SLD x y)
(Rsh64Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SRD x y)
(Rsh32Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SRW x y)
(Rsh16Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SRD (MOVHZreg x) y)
(Rsh8Ux(64|32|16|8)  x y) && shiftIsBounded(v) => (SRD (MOVBZreg x) y)
(Rsh64x(64|32|16|8)  x y) && shiftIsBounded(v) => (SRAD x y)
(Rsh32x(64|32|16|8)  x y) && shiftIsBounded(v) => (SRAW x y)
(Rsh16x(64|32|16|8)  x y) && shiftIsBounded(v) => (SRAD (MOVHreg x) y)
(Rsh8x(64|32|16|8)   x y) && shiftIsBounded(v) => (SRAD (MOVBreg x) y)

// Unbounded shifts. Go shifts saturate to 0 or -1 when shifting beyond the number of
// bits in a type, PPC64 shifts do not (see the ISA for details).
//
// Note, y is always non-negative.
//
// Note, ISELZ is intentionally not used in lower. Where possible, ISEL is converted to ISELZ in late lower
// after all the ISEL folding rules have been exercised.

((Rsh64U|Lsh64)x64 <t> x y)  => (ISEL [0] (S(R|L)D <t> x y) (MOVDconst [0])        (CMPUconst y [64]))
((Rsh64U|Lsh64)x32 <t> x y)  => (ISEL [0] (S(R|L)D <t> x y) (MOVDconst [0])        (CMPWUconst y [64]))
((Rsh64U|Lsh64)x16 <t> x y)  => (ISEL [2] (S(R|L)D <t> x y) (MOVDconst [0])        (Select1 <types.TypeFlags> (ANDCCconst [0xFFC0] y)))
((Rsh64U|Lsh64)x8  <t> x y)  => (ISEL [2] (S(R|L)D <t> x y) (MOVDconst [0])        (Select1 <types.TypeFlags> (ANDCCconst [0x00C0] y)))
(Rsh64x(64|32)     <t> x y)  => (ISEL [0] (SRAD    <t> x y) (SRADconst <t> x [63]) (CMP(U|WU)const y [64]))
(Rsh64x16          <t> x y)  => (ISEL [2] (SRAD    <t> x y) (SRADconst <t> x [63]) (Select1 <types.TypeFlags> (ANDCCconst [0xFFC0] y)))
(Rsh64x8           <t> x y)  => (ISEL [2] (SRAD    <t> x y) (SRADconst <t> x [63]) (Select1 <types.TypeFlags> (ANDCCconst [0x00C0] y)))

((Rsh32U|Lsh32)x64 <t> x y)  => (ISEL [0] (S(R|L)W <t> x y) (MOVDconst [0])        (CMPUconst y [32]))
((Rsh32U|Lsh32)x32 <t> x y)  => (ISEL [0] (S(R|L)W <t> x y) (MOVDconst [0])        (CMPWUconst y [32]))
((Rsh32U|Lsh32)x16 <t> x y)  => (ISEL [2] (S(R|L)W <t> x y) (MOVDconst [0])        (Select1 <types.TypeFlags> (ANDCCconst [0xFFE0] y)))
((Rsh32U|Lsh32)x8  <t> x y)  => (ISEL [2] (S(R|L)W <t> x y) (MOVDconst [0])        (Select1 <types.TypeFlags> (ANDCCconst [0x00E0] y)))
(Rsh32x(64|32)     <t> x y)  => (ISEL [0] (SRAW    <t> x y) (SRAWconst <t> x [31]) (CMP(U|WU)const y [32]))
(Rsh32x16          <t> x y)  => (ISEL [2] (SRAW    <t> x y) (SRAWconst <t> x [31]) (Select1 <types.TypeFlags> (ANDCCconst [0xFFE0] y)))
(Rsh32x8           <t> x y)  => (ISEL [2] (SRAW    <t> x y) (SRAWconst <t> x [31]) (Select1 <types.TypeFlags> (ANDCCconst [0x00E0] y)))

((Rsh16U|Lsh16)x64 <t> x y) => (ISEL [0] (S(R|L)D  <t> (MOVHZreg x) y) (MOVDconst [0])                   (CMPUconst  y [16]))
((Rsh16U|Lsh16)x32 <t> x y) => (ISEL [0] (S(R|L)D  <t> (MOVHZreg x) y) (MOVDconst [0])                   (CMPWUconst y [16]))
((Rsh16U|Lsh16)x16 <t> x y) => (ISEL [2] (S(R|L)D  <t> (MOVHZreg x) y) (MOVDconst [0])                   (Select1 <types.TypeFlags> (ANDCCconst [0xFFF0] y)))
((Rsh16U|Lsh16)x8  <t> x y) => (ISEL [2] (S(R|L)D  <t> (MOVHZreg x) y) (MOVDconst [0])                   (Select1 <types.TypeFlags> (ANDCCconst [0x00F0] y)))
(Rsh16x(64|32)     <t> x y) => (ISEL [0] (SRAD     <t> (MOVHreg  x) y) (SRADconst <t>  (MOVHreg x) [15]) (CMP(U|WU)const  y [16]))
(Rsh16x16          <t> x y) => (ISEL [2] (SRAD     <t> (MOVHreg  x) y) (SRADconst <t>  (MOVHreg x) [15]) (Select1 <types.TypeFlags> (ANDCCconst [0xFFF0] y)))
(Rsh16x8           <t> x y) => (ISEL [2] (SRAD     <t> (MOVHreg  x) y) (SRADconst <t>  (MOVHreg x) [15]) (Select1 <types.TypeFlags> (ANDCCconst [0x00F0] y)))

((Rsh8U|Lsh8)x64 <t> x y) => (ISEL [0] (S(R|L)D  <t> (MOVBZreg x) y) (MOVDconst [0])                  (CMPUconst  y [8]))
((Rsh8U|Lsh8)x32 <t> x y) => (ISEL [0] (S(R|L)D  <t> (MOVBZreg x) y) (MOVDconst [0])                  (CMPWUconst y [8]))
((Rsh8U|Lsh8)x16 <t> x y) => (ISEL [2] (S(R|L)D  <t> (MOVBZreg x) y) (MOVDconst [0])                  (Select1 <types.TypeFlags> (ANDCCconst [0xFFF8] y)))
((Rsh8U|Lsh8)x8  <t> x y) => (ISEL [2] (S(R|L)D  <t> (MOVBZreg x) y) (MOVDconst [0])                  (Select1 <types.TypeFlags> (ANDCCconst [0x00F8] y)))
(Rsh8x(64|32)    <t> x y) => (ISEL [0] (SRAD     <t> (MOVBreg  x) y) (SRADconst <t>  (MOVBreg x) [7]) (CMP(U|WU)const  y [8]))
(Rsh8x16         <t> x y) => (ISEL [2] (SRAD     <t> (MOVBreg  x) y) (SRADconst <t>  (MOVBreg x) [7]) (Select1 <types.TypeFlags> (ANDCCconst [0xFFF8] y)))
(Rsh8x8          <t> x y) => (ISEL [2] (SRAD     <t> (MOVBreg  x) y) (SRADconst <t>  (MOVBreg x) [7]) (Select1 <types.TypeFlags> (ANDCCconst [0x00F8] y)))

// Catch bounded shifts in situations like foo<<uint(shift&63) which might not be caught by the prove pass.
(CMP(U|WU)const [d] (Select0 (ANDCCconst z [c]))) && uint64(d) > uint64(c) => (FlagLT)

(ORN x (MOVDconst [-1])) => x

(S(RAD|RD|LD) x (MOVDconst [c])) => (S(RAD|RD|LD)const [c&63 | (c>>6&1*63)] x)
(S(RAW|RW|LW) x (MOVDconst [c])) => (S(RAW|RW|LW)const [c&31 | (c>>5&1*31)] x)

(Addr {sym} base) => (MOVDaddr {sym} [0] base)
(LocalAddr <t> {sym} base mem) && t.Elem().HasPointers() => (MOVDaddr {sym} (SPanchored base mem))
(LocalAddr <t> {sym} base _)  && !t.Elem().HasPointers() => (MOVDaddr {sym} base)
(OffPtr [off] ptr) => (ADD (MOVDconst <typ.Int64> [off]) ptr)
(MOVDaddr {sym} [n] p:(ADD x y)) && sym == nil && n == 0 => p
(MOVDaddr {sym} [n] ptr) && sym == nil && n == 0 && (ptr.Op == OpArgIntReg || ptr.Op == OpPhi) => ptr

// TODO: optimize these cases?
(Ctz32NonZero ...) => (Ctz32 ...)
(Ctz64NonZero ...) => (Ctz64 ...)

(Ctz64 x) && buildcfg.GOPPC64<=8 => (POPCNTD (ANDN <typ.Int64> (ADDconst <typ.Int64> [-1] x) x))
(Ctz64 x) => (CNTTZD x)
(Ctz32 x) && buildcfg.GOPPC64<=8 => (POPCNTW (MOVWZreg (ANDN <typ.Int> (ADDconst <typ.Int> [-1] x) x)))
(Ctz32 x) => (CNTTZW (MOVWZreg x))
(Ctz16 x) => (POPCNTW (MOVHZreg (ANDN <typ.Int16> (ADDconst <typ.Int16> [-1] x) x)))
(Ctz8 x)  => (POPCNTB (MOVBZreg (ANDN <typ.UInt8> (ADDconst <typ.UInt8> [-1] x) x)))

(BitLen64 x) => (SUBFCconst [64] (CNTLZD <typ.Int> x))
(BitLen32 x) => (SUBFCconst [32] (CNTLZW <typ.Int> x))

(PopCount64 ...) => (POPCNTD ...)
(PopCount(32|16|8) x) => (POPCNT(W|W|B) (MOV(W|H|B)Zreg x))

(And(64|32|16|8) ...) => (AND ...)
(Or(64|32|16|8) ...) => (OR ...)
(Xor(64|32|16|8) ...) => (XOR ...)

(Neg(64|32|16|8) ...) => (NEG ...)
(Neg(64|32)F ...) => (FNEG ...)

(Com(64|32|16|8) x) => (NOR x x)

// Lowering boolean ops
(AndB ...) => (AND ...)
(OrB ...) => (OR ...)
(Not x) => (XORconst [1] x)

// Merge logical operations
(AND x (NOR y y)) => (ANDN x y)
(OR x (NOR y y)) => (ORN x y)

// Lowering comparisons
(EqB x y)  => (Select0 <typ.Int> (ANDCCconst [1] (EQV x y)))
// Sign extension dependence on operand sign sets up for sign/zero-extension elision later
(Eq(8|16) x y) && x.Type.IsSigned() && y.Type.IsSigned() => (Equal (CMPW (SignExt(8|16)to32 x) (SignExt(8|16)to32 y)))
(Eq(8|16) x y) => (Equal (CMPW (ZeroExt(8|16)to32 x) (ZeroExt(8|16)to32 y)))
(Eq(32|64|Ptr) x y) => (Equal ((CMPW|CMP|CMP) x y))
(Eq(32|64)F x y) => (Equal (FCMPU x y))

(NeqB ...) => (XOR ...)
// Like Eq8 and Eq16, prefer sign extension likely to enable later elision.
(Neq(8|16) x y) && x.Type.IsSigned() && y.Type.IsSigned() => (NotEqual (CMPW (SignExt(8|16)to32 x) (SignExt(8|16)to32 y)))
(Neq(8|16) x y)  => (NotEqual (CMPW (ZeroExt(8|16)to32 x) (ZeroExt(8|16)to32 y)))
(Neq(32|64|Ptr) x y) => (NotEqual ((CMPW|CMP|CMP) x y))
(Neq(32|64)F x y) => (NotEqual (FCMPU x y))

(Less(8|16) x y)  => (LessThan (CMPW (SignExt(8|16)to32 x) (SignExt(8|16)to32 y)))
(Less(32|64) x y) => (LessThan ((CMPW|CMP) x y))
(Less(32|64)F x y) => (FLessThan (FCMPU x y))

(Less(8|16)U x y)  => (LessThan (CMPWU (ZeroExt(8|16)to32 x) (ZeroExt(8|16)to32 y)))
(Less(32|64)U x y) => (LessThan ((CMPWU|CMPU) x y))

(Leq(8|16) x y)  => (LessEqual (CMPW (SignExt(8|16)to32 x) (SignExt(8|16)to32 y)))
(Leq(32|64) x y) => (LessEqual ((CMPW|CMP) x y))
(Leq(32|64)F x y) => (FLessEqual (FCMPU x y))

(Leq(8|16)U x y)  => (LessEqual (CMPWU (ZeroExt(8|16)to32 x) (ZeroExt(8|16)to32 y)))
(Leq(32|64)U x y) => (LessEqual (CMP(WU|U) x y))

// Absorb pseudo-ops into blocks.
(If (Equal cc) yes no) => (EQ cc yes no)
(If (NotEqual cc) yes no) => (NE cc yes no)
(If (LessThan cc) yes no) => (LT cc yes no)
(If (LessEqual cc) yes no) => (LE cc yes no)
(If (GreaterThan cc) yes no) => (GT cc yes no)
(If (GreaterEqual cc) yes no) => (GE cc yes no)
(If (FLessThan cc) yes no) => (FLT cc yes no)
(If (FLessEqual cc) yes no) => (FLE cc yes no)
(If (FGreaterThan cc) yes no) => (FGT cc yes no)
(If (FGreaterEqual cc) yes no) => (FGE cc yes no)

(If cond yes no) => (NE (CMPWconst [0] (Select0 <typ.UInt32> (ANDCCconst [1] cond))) yes no)

// Absorb boolean tests into block
(NE (CMPWconst [0] (Select0 (ANDCCconst [1] ((Equal|NotEqual|LessThan|LessEqual|GreaterThan|GreaterEqual) cc)))) yes no) => ((EQ|NE|LT|LE|GT|GE) cc yes no)
(NE (CMPWconst [0] (Select0 (ANDCCconst [1] ((FLessThan|FLessEqual|FGreaterThan|FGreaterEqual) cc)))) yes no) => ((FLT|FLE|FGT|FGE) cc yes no)

// absorb flag constants into branches
(EQ (FlagEQ) yes no) => (First yes no)
(EQ (FlagLT) yes no) => (First no yes)
(EQ (FlagGT) yes no) => (First no yes)

(NE (FlagEQ) yes no) => (First no yes)
(NE (FlagLT) yes no) => (First yes no)
(NE (FlagGT) yes no) => (First yes no)

(LT (FlagEQ) yes no) => (First no yes)
(LT (FlagLT) yes no) => (First yes no)
(LT (FlagGT) yes no) => (First no yes)

(LE (FlagEQ) yes no) => (First yes no)
(LE (FlagLT) yes no) => (First yes no)
(LE (FlagGT) yes no) => (First no yes)

(GT (FlagEQ) yes no) => (First no yes)
(GT (FlagLT) yes no) => (First no yes)
(GT (FlagGT) yes no) => (First yes no)

(GE (FlagEQ) yes no) => (First yes no)
(GE (FlagLT) yes no) => (First no yes)
(GE (FlagGT) yes no) => (First yes no)

// absorb InvertFlags into branches
(LT (InvertFlags cmp) yes no) => (GT cmp yes no)
(GT (InvertFlags cmp) yes no) => (LT cmp yes no)
(LE (InvertFlags cmp) yes no) => (GE cmp yes no)
(GE (InvertFlags cmp) yes no) => (LE cmp yes no)
(EQ (InvertFlags cmp) yes no) => (EQ cmp yes no)
(NE (InvertFlags cmp) yes no) => (NE cmp yes no)

// constant comparisons
(CMPWconst (MOVDconst [x]) [y]) && int32(x)==int32(y) => (FlagEQ)
(CMPWconst (MOVDconst [x]) [y]) && int32(x)<int32(y)  => (FlagLT)
(CMPWconst (MOVDconst [x]) [y]) && int32(x)>int32(y)  => (FlagGT)

(CMPconst (MOVDconst [x]) [y]) && x==y => (FlagEQ)
(CMPconst (MOVDconst [x]) [y]) && x<y  => (FlagLT)
(CMPconst (MOVDconst [x]) [y]) && x>y  => (FlagGT)

(CMPWUconst (MOVDconst [x]) [y]) && int32(x)==int32(y)  => (FlagEQ)
(CMPWUconst (MOVDconst [x]) [y]) && uint32(x)<uint32(y) => (FlagLT)
(CMPWUconst (MOVDconst [x]) [y]) && uint32(x)>uint32(y) => (FlagGT)

(CMPUconst (MOVDconst [x]) [y]) && x==y  => (FlagEQ)
(CMPUconst (MOVDconst [x]) [y]) && uint64(x)<uint64(y) => (FlagLT)
(CMPUconst (MOVDconst [x]) [y]) && uint64(x)>uint64(y) => (FlagGT)

// absorb flag constants into boolean values
(Equal (FlagEQ)) => (MOVDconst [1])
(Equal (FlagLT)) => (MOVDconst [0])
(Equal (FlagGT)) => (MOVDconst [0])

(NotEqual (FlagEQ)) => (MOVDconst [0])
(NotEqual (FlagLT)) => (MOVDconst [1])
(NotEqual (FlagGT)) => (MOVDconst [1])

(LessThan (FlagEQ)) => (MOVDconst [0])
(LessThan (FlagLT)) => (MOVDconst [1])
(LessThan (FlagGT)) => (MOVDconst [0])

(LessEqual (FlagEQ)) => (MOVDconst [1])
(LessEqual (FlagLT)) => (MOVDconst [1])
(LessEqual (FlagGT)) => (MOVDconst [0])

(GreaterThan (FlagEQ)) => (MOVDconst [0])
(GreaterThan (FlagLT)) => (MOVDconst [0])
(GreaterThan (FlagGT)) => (MOVDconst [1])

(GreaterEqual (FlagEQ)) => (MOVDconst [1])
(GreaterEqual (FlagLT)) => (MOVDconst [0])
(GreaterEqual (FlagGT)) => (MOVDconst [1])

// absorb InvertFlags into boolean values
((Equal|NotEqual|LessThan|GreaterThan|LessEqual|GreaterEqual) (InvertFlags x)) => ((Equal|NotEqual|GreaterThan|LessThan|GreaterEqual|LessEqual) x)


// Elide compares of bit tests
((EQ|NE|LT|LE|GT|GE) (CMPconst [0] (Select0 z:(ANDCCconst [c] x))) yes no) => ((EQ|NE|LT|LE|GT|GE) (Select1 <types.TypeFlags> z) yes no)
((EQ|NE|LT|LE|GT|GE) (CMPWconst [0] (Select0 z:(ANDCCconst [c] x))) yes no) => ((EQ|NE|LT|LE|GT|GE) (Select1 <types.TypeFlags> z) yes no)
((EQ|NE|LT|LE|GT|GE) (CMPconst [0] z:(AND x y)) yes no) && z.Uses == 1 => ((EQ|NE|LT|LE|GT|GE) (Select1 <types.TypeFlags> (ANDCC x y)) yes no)
((EQ|NE|LT|LE|GT|GE) (CMPconst [0] z:(OR x y)) yes no) && z.Uses == 1 => ((EQ|NE|LT|LE|GT|GE) (Select1 <types.TypeFlags> (ORCC x y)) yes no)
((EQ|NE|LT|LE|GT|GE) (CMPconst [0] z:(XOR x y)) yes no) && z.Uses == 1 => ((EQ|NE|LT|LE|GT|GE) (Select1 <types.TypeFlags> (XORCC x y)) yes no)

(CondSelect x y (SETBC [a] cmp))  => (ISEL [a] x y cmp)
(CondSelect x y (SETBCR [a] cmp))  => (ISEL [a+4] x y cmp)
// Only lower after bool is lowered. It should always lower. This helps ensure the folding below happens reliably.
(CondSelect x y bool) && flagArg(bool) == nil => (ISEL [6] x y (Select1 <types.TypeFlags> (ANDCCconst [1] bool)))
// Fold any CR -> GPR -> CR transfers when applying the above rule.
(ISEL [6] x y (Select1 (ANDCCconst [1] (SETBC [c] cmp)))) => (ISEL [c] x y cmp)
(ISEL [6] x y ((CMP|CMPW)const [0] (SETBC [c] cmp))) => (ISEL [c] x y cmp)
(ISEL [6] x y ((CMP|CMPW)const [0] (SETBCR [c] cmp))) => (ISEL [c+4] x y cmp)

// Lowering loads
(Load <t> ptr mem) && (is64BitInt(t) || isPtr(t)) => (MOVDload ptr mem)
(Load <t> ptr mem) && is32BitInt(t) &&  t.IsSigned() => (MOVWload ptr mem)
(Load <t> ptr mem) && is32BitInt(t) && !t.IsSigned() => (MOVWZload ptr mem)
(Load <t> ptr mem) && is16BitInt(t) &&  t.IsSigned() => (MOVHload ptr mem)
(Load <t> ptr mem) && is16BitInt(t) && !t.IsSigned() => (MOVHZload ptr mem)
(Load <t> ptr mem) && t.IsBoolean() => (MOVBZload ptr mem)
(Load <t> ptr mem) && is8BitInt(t) &&  t.IsSigned() => (MOVBreg (MOVBZload ptr mem)) // PPC has no signed-byte load.
(Load <t> ptr mem) && is8BitInt(t) && !t.IsSigned() => (MOVBZload ptr mem)

(Load <t> ptr mem) && is32BitFloat(t) => (FMOVSload ptr mem)
(Load <t> ptr mem) && is64BitFloat(t) => (FMOVDload ptr mem)

(Store {t} ptr val mem) && t.Size() == 8 &&  t.IsFloat() => (FMOVDstore ptr val mem)
(Store {t} ptr val mem) && t.Size() == 4 &&  t.IsFloat() => (FMOVSstore ptr val mem)
(Store {t} ptr val mem) && t.Size() == 8 && !t.IsFloat() => (MOVDstore ptr val mem)
(Store {t} ptr val mem) && t.Size() == 4 && !t.IsFloat() => (MOVWstore ptr val mem)
(Store {t} ptr val mem) && t.Size() == 2 => (MOVHstore ptr val mem)
(Store {t} ptr val mem) && t.Size() == 1 => (MOVBstore ptr val mem)

// Using Zero instead of LoweredZero allows the
// target address to be folded where possible.
(Zero [0] _ mem) => mem
(Zero [1] destptr mem) => (MOVBstorezero destptr mem)
(Zero [2] destptr mem) =>
	(MOVHstorezero destptr mem)
(Zero [3] destptr mem) =>
	(MOVBstorezero [2] destptr
		(MOVHstorezero destptr mem))
(Zero [4] destptr mem) =>
	(MOVWstorezero destptr mem)
(Zero [5] destptr mem) =>
	(MOVBstorezero [4] destptr
        	(MOVWstorezero destptr mem))
(Zero [6] destptr mem) =>
	(MOVHstorezero [4] destptr
		(MOVWstorezero destptr mem))
(Zero [7] destptr mem) =>
	(MOVBstorezero [6] destptr
		(MOVHstorezero [4] destptr
			(MOVWstorezero destptr mem)))

(Zero [8] {t} destptr mem) => (MOVDstorezero destptr mem)
(Zero [12] {t} destptr mem) =>
        (MOVWstorezero [8] destptr
                (MOVDstorezero [0] destptr mem))
(Zero [16] {t} destptr mem) =>
       (MOVDstorezero [8] destptr
                (MOVDstorezero [0] destptr mem))
(Zero [24] {t} destptr mem) =>
       (MOVDstorezero [16] destptr
               (MOVDstorezero [8] destptr
                       (MOVDstorezero [0] destptr mem)))
(Zero [32] {t} destptr mem) =>
       (MOVDstorezero [24] destptr
               (MOVDstorezero [16] destptr
                       (MOVDstorezero [8] destptr
                               (MOVDstorezero [0] destptr mem))))

// Handle cases not handled above
// Lowered Short cases do not generate loops, and as a result don't clobber
// the address registers or flags.
(Zero [s] ptr mem) && buildcfg.GOPPC64 <= 8 && s < 64 => (LoweredZeroShort [s] ptr mem)
(Zero [s] ptr mem) && buildcfg.GOPPC64 <= 8 => (LoweredZero [s] ptr mem)
(Zero [s] ptr mem) && s < 128 && buildcfg.GOPPC64 >= 9 => (LoweredQuadZeroShort [s] ptr mem)
(Zero [s] ptr mem) && buildcfg.GOPPC64 >= 9 => (LoweredQuadZero [s] ptr mem)

// moves
(Move [0] _ _ mem) => mem
(Move [1] dst src mem) => (MOVBstore dst (MOVBZload src mem) mem)
(Move [2] dst src mem) =>
        (MOVHstore dst (MOVHZload src mem) mem)
(Move [4] dst src mem) =>
	(MOVWstore dst (MOVWZload src mem) mem)
// MOVD for load and store must have offsets that are multiple of 4
(Move [8] {t} dst src mem) =>
	(MOVDstore dst (MOVDload src mem) mem)
(Move [3] dst src mem) =>
        (MOVBstore [2] dst (MOVBZload [2] src mem)
                (MOVHstore dst (MOVHload src mem) mem))
(Move [5] dst src mem) =>
        (MOVBstore [4] dst (MOVBZload [4] src mem)
                (MOVWstore dst (MOVWZload src mem) mem))
(Move [6] dst src mem) =>
        (MOVHstore [4] dst (MOVHZload [4] src mem)
                (MOVWstore dst (MOVWZload src mem) mem))
(Move [7] dst src mem) =>
        (MOVBstore [6] dst (MOVBZload [6] src mem)
                (MOVHstore [4] dst (MOVHZload [4] src mem)
                        (MOVWstore dst (MOVWZload src mem) mem)))

// Large move uses a loop. Since the address is computed and the
// offset is zero, any alignment can be used.
(Move [s] dst src mem) && s > 8 && buildcfg.GOPPC64 <= 8 && logLargeCopy(v, s) =>
        (LoweredMove [s] dst src mem)
(Move [s] dst src mem) && s > 8 && s <= 64 && buildcfg.GOPPC64 >= 9 =>
        (LoweredQuadMoveShort [s] dst src mem)
(Move [s] dst src mem) && s > 8 && buildcfg.GOPPC64 >= 9 && logLargeCopy(v, s) =>
        (LoweredQuadMove [s] dst src mem)

// Calls
// Lowering calls
(StaticCall ...) => (CALLstatic ...)
(ClosureCall ...) => (CALLclosure ...)
(InterCall ...) => (CALLinter ...)
(TailCall ...) => (CALLtail ...)

// Miscellaneous
(GetClosurePtr ...) => (LoweredGetClosurePtr ...)
(GetCallerSP ...) => (LoweredGetCallerSP ...)
(GetCallerPC ...) => (LoweredGetCallerPC ...)
(IsNonNil ptr) => (NotEqual (CMPconst [0] ptr))
(IsInBounds idx len) => (LessThan (CMPU idx len))
(IsSliceInBounds idx len) => (LessEqual (CMPU idx len))
(NilCheck ...) => (LoweredNilCheck ...)

// Write barrier.
(WB ...) => (LoweredWB ...)

// Publication barrier as intrinsic
(PubBarrier ...) => (LoweredPubBarrier ...)

(PanicBounds [kind] x y mem) && boundsABI(kind) == 0 => (LoweredPanicBoundsA [kind] x y mem)
(PanicBounds [kind] x y mem) && boundsABI(kind) == 1 => (LoweredPanicBoundsB [kind] x y mem)
(PanicBounds [kind] x y mem) && boundsABI(kind) == 2 => (LoweredPanicBoundsC [kind] x y mem)

// Optimizations
// Note that PPC "logical" immediates come in 0:15 and 16:31 unsigned immediate forms,
// so ORconst, XORconst easily expand into a pair.

// Include very-large constants in the const-const case.
(AND (MOVDconst [c]) (MOVDconst [d])) => (MOVDconst [c&d])
(OR (MOVDconst [c]) (MOVDconst [d])) => (MOVDconst [c|d])
(XOR (MOVDconst [c]) (MOVDconst [d])) => (MOVDconst [c^d])
(ORN (MOVDconst [c]) (MOVDconst [d])) => (MOVDconst [c|^d])
(ANDN (MOVDconst [c]) (MOVDconst [d])) => (MOVDconst [c&^d])
(NOR (MOVDconst [c]) (MOVDconst [d])) => (MOVDconst [^(c|d)])

// Discover consts
(AND x (MOVDconst [-1])) => x
(AND x (MOVDconst [c])) && isU16Bit(c) => (Select0 (ANDCCconst [c] x))
(XOR x (MOVDconst [c])) && isU32Bit(c) => (XORconst [c] x)
(OR x (MOVDconst [c])) && isU32Bit(c) => (ORconst [c] x)

// Simplify consts
(ANDCCconst [c] (Select0 (ANDCCconst [d] x))) => (ANDCCconst [c&d] x)
(ORconst [c] (ORconst [d] x)) => (ORconst [c|d] x)
(XORconst [c] (XORconst [d] x)) => (XORconst [c^d] x)
(Select0 (ANDCCconst [-1] x)) => x
(Select0 (ANDCCconst [0] _)) => (MOVDconst [0])
(Select1 (ANDCCconst [0] _)) => (FlagEQ)
(XORconst [0] x) => x
(ORconst [-1] _) => (MOVDconst [-1])
(ORconst [0] x) => x

// zero-extend of small and => small and
(MOVBZreg y:(Select0 (ANDCCconst [c] _))) && uint64(c) <= 0xFF => y
(MOVHZreg y:(Select0 (ANDCCconst [c] _))) && uint64(c) <= 0xFFFF => y
(MOVWZreg y:(Select0 (ANDCCconst [c] _))) && uint64(c) <= 0xFFFFFFFF => y
(MOVWZreg y:(AND (MOVDconst [c]) _)) && uint64(c) <= 0xFFFFFFFF => y

// sign extend of small-positive and => small-positive-and
(MOVBreg y:(Select0 (ANDCCconst [c] _))) && uint64(c) <= 0x7F => y
(MOVHreg y:(Select0 (ANDCCconst [c] _))) && uint64(c) <= 0x7FFF => y
(MOVWreg y:(Select0 (ANDCCconst [c] _))) && uint64(c) <= 0xFFFF => y // 0xFFFF is largest immediate constant, when regarded as 32-bit is > 0
(MOVWreg y:(AND (MOVDconst [c]) _)) && uint64(c) <= 0x7FFFFFFF => y

// small and of zero-extend => either zero-extend or small and
(Select0 (ANDCCconst [c] y:(MOVBZreg _))) && c&0xFF == 0xFF => y
(Select0 (ANDCCconst [0xFF] (MOVBreg x))) => (MOVBZreg x)
(Select0 (ANDCCconst [c] y:(MOVHZreg _)))  && c&0xFFFF == 0xFFFF => y
(Select0 (ANDCCconst [0xFFFF] (MOVHreg x))) => (MOVHZreg x)

(AND (MOVDconst [c]) y:(MOVWZreg _))  && c&0xFFFFFFFF == 0xFFFFFFFF => y
(AND (MOVDconst [0xFFFFFFFF]) y:(MOVWreg x)) => (MOVWZreg x)
// normal case
(Select0 (ANDCCconst [c] (MOVBZreg x))) => (Select0 (ANDCCconst [c&0xFF] x))
(Select0 (ANDCCconst [c] (MOVHZreg x))) => (Select0 (ANDCCconst [c&0xFFFF] x))
(Select0 (ANDCCconst [c] (MOVWZreg x))) => (Select0 (ANDCCconst [c&0xFFFFFFFF] x))

// Eliminate unnecessary sign/zero extend following right shift
(MOV(B|H|W)Zreg (SRWconst [c] (MOVBZreg x))) => (SRWconst [c] (MOVBZreg x))
(MOV(H|W)Zreg (SRWconst [c] (MOVHZreg x))) => (SRWconst [c] (MOVHZreg x))
(MOVWZreg (SRWconst [c] (MOVWZreg x))) => (SRWconst [c] (MOVWZreg x))
(MOV(B|H|W)reg (SRAWconst [c] (MOVBreg x))) => (SRAWconst [c] (MOVBreg x))
(MOV(H|W)reg (SRAWconst [c] (MOVHreg x))) => (SRAWconst [c] (MOVHreg x))
(MOVWreg (SRAWconst [c] (MOVWreg x))) => (SRAWconst [c] (MOVWreg x))

(MOV(WZ|W)reg (S(R|RA)Wconst [c] x)) && sizeof(x.Type) <= 32 => (S(R|RA)Wconst [c] x)
(MOV(HZ|H)reg (S(R|RA)Wconst [c] x)) && sizeof(x.Type) <= 16 => (S(R|RA)Wconst [c] x)
(MOV(BZ|B)reg (S(R|RA)Wconst [c] x)) && sizeof(x.Type) == 8 => (S(R|RA)Wconst [c] x)

// initial right shift will handle sign/zero extend
(MOVBZreg (SRDconst [c] x)) && c>=56 => (SRDconst [c] x)
(MOVBreg (SRDconst [c] x)) && c>56 => (SRDconst [c] x)
(MOVBreg (SRDconst [c] x)) && c==56 => (SRADconst [c] x)
(MOVBreg (SRADconst [c] x)) && c>=56 => (SRADconst [c] x)
(MOVBZreg (SRWconst [c] x)) && c>=24 => (SRWconst [c] x)
(MOVBreg (SRWconst [c] x)) && c>24 => (SRWconst [c] x)
(MOVBreg (SRWconst [c] x)) && c==24 => (SRAWconst [c] x)
(MOVBreg (SRAWconst [c] x)) && c>=24 => (SRAWconst [c] x)

(MOVHZreg (SRDconst [c] x)) && c>=48 => (SRDconst [c] x)
(MOVHreg (SRDconst [c] x)) && c>48 => (SRDconst [c] x)
(MOVHreg (SRDconst [c] x)) && c==48 => (SRADconst [c] x)
(MOVHreg (SRADconst [c] x)) && c>=48 => (SRADconst [c] x)
(MOVHZreg (SRWconst [c] x)) && c>=16 => (SRWconst [c] x)
(MOVHreg (SRWconst [c] x)) && c>16 => (SRWconst [c] x)
(MOVHreg (SRAWconst [c] x)) && c>=16 => (SRAWconst [c] x)
(MOVHreg (SRWconst [c] x)) && c==16 => (SRAWconst [c] x)

(MOVWZreg (SRDconst [c] x)) && c>=32 => (SRDconst [c] x)
(MOVWreg (SRDconst [c] x)) && c>32 => (SRDconst [c] x)
(MOVWreg (SRADconst [c] x)) && c>=32 => (SRADconst [c] x)
(MOVWreg (SRDconst [c] x)) && c==32 => (SRADconst [c] x)

// Various redundant zero/sign extension combinations.
(MOVBZreg y:(MOVBZreg _)) => y  // repeat
(MOVBreg y:(MOVBreg _)) => y // repeat
(MOVBreg (MOVBZreg x)) => (MOVBreg x)
(MOVBZreg (MOVBreg x)) => (MOVBZreg x)

// H - there are more combinations than these

(MOVHZreg y:(MOV(H|B)Zreg _)) => y // repeat
(MOVHZreg y:(MOVHBRload _ _)) => y

(MOVHreg y:(MOV(H|B)reg _)) => y // repeat

(MOV(H|HZ)reg y:(MOV(HZ|H)reg x)) => (MOV(H|HZ)reg x)

// W - there are more combinations than these

(MOV(WZ|WZ|WZ|W|W|W)reg y:(MOV(WZ|HZ|BZ|W|H|B)reg _)) => y // repeat
(MOVWZreg y:(MOV(H|W)BRload _ _)) => y

(MOV(W|WZ)reg y:(MOV(WZ|W)reg x)) => (MOV(W|WZ)reg x)

// Truncate then logical then truncate: omit first, lesser or equal truncate
(MOVWZreg ((OR|XOR|AND) <t> x (MOVWZreg y))) => (MOVWZreg ((OR|XOR|AND) <t> x y))
(MOVHZreg ((OR|XOR|AND) <t> x (MOVWZreg y))) => (MOVHZreg ((OR|XOR|AND) <t> x y))
(MOVHZreg ((OR|XOR|AND) <t> x (MOVHZreg y))) => (MOVHZreg ((OR|XOR|AND) <t> x y))
(MOVBZreg ((OR|XOR|AND) <t> x (MOVWZreg y))) => (MOVBZreg ((OR|XOR|AND) <t> x y))
(MOVBZreg ((OR|XOR|AND) <t> x (MOVHZreg y))) => (MOVBZreg ((OR|XOR|AND) <t> x y))
(MOVBZreg ((OR|XOR|AND) <t> x (MOVBZreg y))) => (MOVBZreg ((OR|XOR|AND) <t> x y))

(MOV(B|H|W)Zreg z:(Select0 (ANDCCconst [c] (MOVBZload ptr x)))) => z
(MOV(B|H|W)Zreg z:(AND y (MOV(B|H|W)Zload ptr x))) => z
(MOV(H|W)Zreg z:(Select0 (ANDCCconst [c] (MOVHZload ptr x)))) => z
(MOVWZreg z:(Select0 (ANDCCconst [c] (MOVWZload ptr x)))) => z

// Arithmetic constant ops

(ADD x (MOVDconst <t> [c])) && is32Bit(c) && !t.IsPtr() => (ADDconst [c] x)
(ADDconst [c] (ADDconst [d] x)) && is32Bit(c+d) => (ADDconst [c+d] x)
(ADDconst [0] x) => x
(SUB x (MOVDconst [c])) && is32Bit(-c) => (ADDconst [-c] x)

(ADDconst [c] (MOVDaddr [d] {sym} x)) && is32Bit(c+int64(d)) => (MOVDaddr [int32(c+int64(d))] {sym} x)
(ADDconst [c] x:(SP)) && is32Bit(c) => (MOVDaddr [int32(c)] x) // so it is rematerializeable

(MULL(W|D) x (MOVDconst [c])) && is16Bit(c) => (MULL(W|D)const [int32(c)] x)

// Subtract from (with carry, but ignored) constant.
// Note, these clobber the carry bit.
(SUB (MOVDconst [c]) x) && is32Bit(c) => (SUBFCconst [c] x)
(SUBFCconst [c] (NEG x)) => (ADDconst [c] x)
(SUBFCconst [c] (SUBFCconst [d] x)) && is32Bit(c-d) => (ADDconst [c-d] x)
(SUBFCconst [0] x) => (NEG x)
(ADDconst [c] (SUBFCconst [d] x)) && is32Bit(c+d) => (SUBFCconst [c+d] x)
(NEG (ADDconst [c] x)) && is32Bit(-c) => (SUBFCconst [-c] x)
(NEG (SUBFCconst [c] x)) && is32Bit(-c) => (ADDconst [-c] x)
(NEG (SUB x y)) => (SUB y x)
(NEG (NEG x)) => x

// Use register moves instead of stores and loads to move int<=>float values
// Common with math Float64bits, Float64frombits
(MOVDload [off] {sym} ptr (FMOVDstore [off] {sym} ptr x _)) => (MFVSRD x)
(FMOVDload [off] {sym} ptr (MOVDstore [off] {sym} ptr x _)) => (MTVSRD x)

(FMOVDstore [off] {sym} ptr (MTVSRD x) mem) => (MOVDstore [off] {sym} ptr x mem)
(MOVDstore [off] {sym} ptr (MFVSRD x) mem) => (FMOVDstore [off] {sym} ptr x mem)

(MTVSRD (MOVDconst [c])) && !math.IsNaN(math.Float64frombits(uint64(c))) => (FMOVDconst [math.Float64frombits(uint64(c))])
(MFVSRD (FMOVDconst [c])) => (MOVDconst [int64(math.Float64bits(c))])

(MTVSRD x:(MOVDload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (FMOVDload [off] {sym} ptr mem)
(MFVSRD x:(FMOVDload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVDload [off] {sym} ptr mem)

// Rules for MOV* or FMOV* ops determine when indexed (MOV*loadidx or MOV*storeidx)
// or non-indexed (MOV*load or MOV*store) should be used. Indexed instructions
// require an extra instruction and register to load the index so non-indexed is preferred.
// Indexed ops generate indexed load or store instructions for all GOPPC64 values.
// Non-indexed ops generate DS-form loads and stores when the offset fits in 16 bits,
// and on power8 and power9, a multiple of 4 is required for MOVW and MOVD ops.
// On power10, prefixed loads and stores can be used for offsets > 16 bits and <= 32 bits.
// and support for PC relative addressing must be available if relocation is needed.
// On power10, the assembler will determine when to use DS-form or prefixed
// instructions for non-indexed ops depending on the value of the offset.
//
// Fold offsets for stores.
(MOV(D|W|H|B)store [off1] {sym} (ADDconst [off2] x) val mem) && (is16Bit(int64(off1)+off2) || (supportsPPC64PCRel() && is32Bit(int64(off1)+off2))) => (MOV(D|W|H|B)store [off1+int32(off2)] {sym} x val mem)

(FMOV(S|D)store [off1] {sym} (ADDconst [off2] ptr) val mem) && (is16Bit(int64(off1)+off2) || (supportsPPC64PCRel() && is32Bit(int64(off1)+off2))) => (FMOV(S|D)store [off1+int32(off2)] {sym} ptr val mem)

// Fold address into load/store.
// If power10 with PCRel is not available, then
// the assembler needs to generate several instructions and use
// temp register for accessing global, and each time it will reload
// the temp register. So don't fold address of global in that case if there is more than
// one use.
(MOV(B|H|W|D)store [off1] {sym1} p:(MOVDaddr [off2] {sym2} ptr) val mem) && canMergeSym(sym1,sym2)
	&& ((is16Bit(int64(off1+off2)) && (ptr.Op != OpSB || p.Uses == 1)) || (supportsPPC64PCRel() && is32Bit(int64(off1+off2)))) =>
        (MOV(B|H|W|D)store [off1+off2] {mergeSym(sym1,sym2)} ptr val mem)

(FMOV(S|D)store [off1] {sym1} p:(MOVDaddr [off2] {sym2} ptr) val mem) && canMergeSym(sym1,sym2)
	&& ((is16Bit(int64(off1+off2)) && (ptr.Op != OpSB || p.Uses == 1)) || (supportsPPC64PCRel() && is32Bit(int64(off1+off2)))) =>
        (FMOV(S|D)store [off1+off2] {mergeSym(sym1,sym2)} ptr val mem)

(MOV(B|H|W)Zload [off1] {sym1} p:(MOVDaddr [off2] {sym2} ptr) mem) && canMergeSym(sym1,sym2)
	&& ((is16Bit(int64(off1+off2)) && (ptr.Op != OpSB || p.Uses == 1)) || (supportsPPC64PCRel() && is32Bit(int64(off1+off2)))) =>
        (MOV(B|H|W)Zload [off1+off2] {mergeSym(sym1,sym2)} ptr mem)
(MOV(H|W|D)load [off1] {sym1} p:(MOVDaddr [off2] {sym2} ptr) mem) && canMergeSym(sym1,sym2)
	&& ((is16Bit(int64(off1+off2)) && (ptr.Op != OpSB || p.Uses == 1)) || (supportsPPC64PCRel() && is32Bit(int64(off1+off2)))) =>
        (MOV(H|W|D)load [off1+off2] {mergeSym(sym1,sym2)} ptr mem)
(FMOV(S|D)load [off1] {sym1} p:(MOVDaddr [off2] {sym2} ptr) mem) && canMergeSym(sym1,sym2)
	&& ((is16Bit(int64(off1+off2)) && (ptr.Op != OpSB || p.Uses == 1)) || (supportsPPC64PCRel() && is32Bit(int64(off1+off2)))) =>
        (FMOV(S|D)load [off1+off2] {mergeSym(sym1,sym2)} ptr mem)

// Fold offsets for loads.
(FMOV(S|D)load [off1] {sym} (ADDconst [off2] ptr) mem) && (is16Bit(int64(off1)+off2) || (supportsPPC64PCRel() && is32Bit(int64(off1)+off2))) => (FMOV(S|D)load [off1+int32(off2)] {sym} ptr mem)

(MOV(D|W|WZ|H|HZ|BZ)load [off1] {sym} (ADDconst [off2] x) mem) && (is16Bit(int64(off1)+off2) || (supportsPPC64PCRel() && is32Bit(int64(off1)+off2))) => (MOV(D|W|WZ|H|HZ|BZ)load [off1+int32(off2)] {sym} x mem)

// Determine load + addressing that can be done as a register indexed load
(MOV(D|W|WZ|H|HZ|BZ)load [0] {sym} p:(ADD ptr idx) mem) && sym == nil && p.Uses == 1 => (MOV(D|W|WZ|H|HZ|BZ)loadidx ptr idx mem)

// See comments above concerning selection of indexed vs. non-indexed ops.
// These cases don't have relocation.
(MOV(D|W)loadidx ptr (MOVDconst [c]) mem) && ((is16Bit(c) && c%4 == 0) || (buildcfg.GOPPC64 >= 10 && is32Bit(c))) => (MOV(D|W)load [int32(c)] ptr mem)
(MOV(WZ|H|HZ|BZ)loadidx ptr (MOVDconst [c]) mem) && (is16Bit(c) || (buildcfg.GOPPC64 >= 10 && is32Bit(c))) => (MOV(WZ|H|HZ|BZ)load [int32(c)] ptr mem)
(MOV(D|W)loadidx (MOVDconst [c]) ptr mem) && ((is16Bit(c) && c%4 == 0) || (buildcfg.GOPPC64 >= 10 && is32Bit(c))) => (MOV(D|W)load [int32(c)] ptr mem)
(MOV(WZ|H|HZ|BZ)loadidx (MOVDconst [c]) ptr mem) && (is16Bit(c) || (buildcfg.GOPPC64 >= 10 && is32Bit(c))) => (MOV(WZ|H|HZ|BZ)load [int32(c)] ptr mem)

// Store of zero => storezero
(MOV(D|W|H|B)store [off] {sym} ptr (MOVDconst [0]) mem) => (MOV(D|W|H|B)storezero [off] {sym} ptr mem)

// Fold offsets for storezero
(MOV(D|W|H|B)storezero [off1] {sym} (ADDconst [off2] x) mem) && ((supportsPPC64PCRel() && is32Bit(int64(off1)+off2)) || (is16Bit(int64(off1)+off2))) =>
    (MOV(D|W|H|B)storezero [off1+int32(off2)] {sym} x mem)

// Stores with addressing that can be done as indexed stores
(MOV(D|W|H|B)store [0] {sym} p:(ADD ptr idx) val mem) && sym == nil && p.Uses == 1 => (MOV(D|W|H|B)storeidx ptr idx val mem)

(MOVDstoreidx ptr (MOVDconst [c]) val mem) && ((is16Bit(c) && c%4 == 0) || (buildcfg.GOPPC64 >= 10 && is32Bit(c))) => (MOVDstore [int32(c)] ptr val mem)
(MOV(W|H|B)storeidx ptr (MOVDconst [c]) val mem) && (is16Bit(c) || (buildcfg.GOPPC64 >= 10 && is32Bit(c))) => (MOV(W|H|B)store [int32(c)] ptr val mem)
(MOVDstoreidx (MOVDconst [c]) ptr val mem) && ((is16Bit(c) && c%4 == 0) || (buildcfg.GOPPC64 >= 10 && is32Bit(c))) => (MOVDstore [int32(c)] ptr val mem)
(MOV(W|H|B)storeidx (MOVDconst [c]) ptr val mem) && (is16Bit(c) || (buildcfg.GOPPC64 >= 10 && is32Bit(c))) => (MOV(W|H|B)store [int32(c)] ptr val mem)

// Fold symbols into storezero
(MOV(D|W|H|B)storezero [off1] {sym1} p:(MOVDaddr [off2] {sym2} x) mem) && canMergeSym(sym1,sym2)
	&& ((is16Bit(int64(off1+off2)) && (x.Op != OpSB || p.Uses == 1)) || (supportsPPC64PCRel() && is32Bit(int64(off1+off2)))) =>
    (MOV(D|W|H|B)storezero [off1+off2] {mergeSym(sym1,sym2)} x mem)

// atomic intrinsics
(AtomicLoad(8|32|64|Ptr)  ptr mem) => (LoweredAtomicLoad(8|32|64|Ptr) [1] ptr mem)
(AtomicLoadAcq(32|64)     ptr mem) => (LoweredAtomicLoad(32|64) [0] ptr mem)

(AtomicStore(8|32|64)    ptr val mem) => (LoweredAtomicStore(8|32|64) [1] ptr val mem)
(AtomicStoreRel(32|64)   ptr val mem) => (LoweredAtomicStore(32|64) [0] ptr val mem)

(AtomicExchange(32|64) ...) => (LoweredAtomicExchange(32|64) ...)

(AtomicAdd(32|64) ...) => (LoweredAtomicAdd(32|64) ...)

(AtomicCompareAndSwap(32|64) ptr old new_ mem) => (LoweredAtomicCas(32|64) [1] ptr old new_ mem)
(AtomicCompareAndSwapRel32   ptr old new_ mem) => (LoweredAtomicCas32 [0] ptr old new_ mem)

(AtomicAnd(8|32)  ...) => (LoweredAtomicAnd(8|32)  ...)
(AtomicOr(8|32)   ...) => (LoweredAtomicOr(8|32)   ...)

(Slicemask <t> x) => (SRADconst (NEG <t> x) [63])
(Select0 (ANDCCconst [1] z:(SRADconst [63] x))) && z.Uses == 1  => (SRDconst [63] x)

// Note that MOV??reg returns a 64-bit int, x is not necessarily that wide
// This may interact with other patterns in the future. (Compare with arm64)
(MOV(B|H|W)Zreg x:(MOVBZload _ _)) => x
(MOV(B|H|W)Zreg x:(MOVBZloadidx _ _ _)) => x
(MOV(H|W)Zreg x:(MOVHZload _ _)) => x
(MOV(H|W)Zreg x:(MOVHZloadidx _ _ _)) => x
(MOV(H|W)reg x:(MOVHload _ _)) => x
(MOV(H|W)reg x:(MOVHloadidx _ _ _)) => x
(MOV(WZ|W)reg x:(MOV(WZ|W)load _ _)) => x
(MOV(WZ|W)reg x:(MOV(WZ|W)loadidx _ _ _)) => x
(MOV(B|W)Zreg x:(Select0 (LoweredAtomicLoad(8|32) _ _))) => x

// don't extend if argument is already extended
(MOVBreg x:(Arg <t>)) && is8BitInt(t) && t.IsSigned() => x
(MOVBZreg x:(Arg <t>)) && is8BitInt(t) && !t.IsSigned() => x
(MOVHreg x:(Arg <t>)) && (is8BitInt(t) || is16BitInt(t)) && t.IsSigned() => x
(MOVHZreg x:(Arg <t>)) && (is8BitInt(t) || is16BitInt(t)) && !t.IsSigned() => x
(MOVWreg x:(Arg <t>)) && (is8BitInt(t) || is16BitInt(t) || is32BitInt(t)) && t.IsSigned() => x
(MOVWZreg x:(Arg <t>)) && (is8BitInt(t) || is16BitInt(t) || is32BitInt(t)) && !t.IsSigned() => x

(MOVBZreg (MOVDconst [c]))  => (MOVDconst [int64(uint8(c))])
(MOVBreg (MOVDconst [c]))  => (MOVDconst [int64(int8(c))])
(MOVHZreg (MOVDconst [c]))  => (MOVDconst [int64(uint16(c))])
(MOVHreg (MOVDconst [c]))  => (MOVDconst [int64(int16(c))])
(MOVWreg (MOVDconst [c])) => (MOVDconst [int64(int32(c))])
(MOVWZreg (MOVDconst [c])) => (MOVDconst [int64(uint32(c))])

// Implement clrsldi and clrslwi extended mnemonics as described in
// ISA 3.0 section C.8. AuxInt field contains values needed for
// the instructions, packed together since there is only one available.
(SLDconst [c] z:(MOVBZreg x)) && c < 8 && z.Uses == 1 => (CLRLSLDI [newPPC64ShiftAuxInt(c,56,63,64)] x)
(SLDconst [c] z:(MOVHZreg x)) && c < 16 && z.Uses == 1 => (CLRLSLDI [newPPC64ShiftAuxInt(c,48,63,64)] x)
(SLDconst [c] z:(MOVWZreg x)) && c < 32 && z.Uses == 1 => (CLRLSLDI [newPPC64ShiftAuxInt(c,32,63,64)] x)

(SLDconst [c] z:(Select0 (ANDCCconst [d] x))) && z.Uses == 1 && isPPC64ValidShiftMask(d) && c <= (64-getPPC64ShiftMaskLength(d)) => (CLRLSLDI [newPPC64ShiftAuxInt(c,64-getPPC64ShiftMaskLength(d),63,64)] x)
(SLDconst [c] z:(AND (MOVDconst [d]) x)) && z.Uses == 1 && isPPC64ValidShiftMask(d) && c<=(64-getPPC64ShiftMaskLength(d)) => (CLRLSLDI [newPPC64ShiftAuxInt(c,64-getPPC64ShiftMaskLength(d),63,64)] x)
(SLWconst [c] z:(MOVBZreg x)) && z.Uses == 1 && c < 8 => (CLRLSLWI [newPPC64ShiftAuxInt(c,24,31,32)] x)
(SLWconst [c] z:(MOVHZreg x)) && z.Uses == 1 && c < 16 => (CLRLSLWI [newPPC64ShiftAuxInt(c,16,31,32)] x)
(SLWconst [c] z:(Select0 (ANDCCconst [d] x))) && z.Uses == 1 && isPPC64ValidShiftMask(d) && c<=(32-getPPC64ShiftMaskLength(d)) => (CLRLSLWI [newPPC64ShiftAuxInt(c,32-getPPC64ShiftMaskLength(d),31,32)] x)
(SLWconst [c] z:(AND (MOVDconst [d]) x)) && z.Uses == 1 && isPPC64ValidShiftMask(d) && c<=(32-getPPC64ShiftMaskLength(d)) => (CLRLSLWI [newPPC64ShiftAuxInt(c,32-getPPC64ShiftMaskLength(d),31,32)] x)
// special case for power9
(SL(W|D)const [c] z:(MOVWreg x)) && c < 32 && buildcfg.GOPPC64 >= 9 => (EXTSWSLconst [c] x)

// Lose widening ops fed to stores
(MOVBstore [off] {sym} ptr (MOV(B|BZ|H|HZ|W|WZ)reg x) mem) => (MOVBstore [off] {sym} ptr x mem)
(MOVHstore [off] {sym} ptr (MOV(H|HZ|W|WZ)reg x) mem) => (MOVHstore [off] {sym} ptr x mem)
(MOVWstore [off] {sym} ptr (MOV(W|WZ)reg x) mem) => (MOVWstore [off] {sym} ptr x mem)
(MOVBstore [off] {sym} ptr (SRWconst (MOV(H|HZ)reg x) [c]) mem) && c <= 8 => (MOVBstore [off] {sym} ptr (SRWconst <typ.UInt32> x [c]) mem)
(MOVBstore [off] {sym} ptr (SRWconst (MOV(W|WZ)reg x) [c]) mem) && c <= 24 => (MOVBstore [off] {sym} ptr (SRWconst <typ.UInt32> x [c]) mem)
(MOVBstoreidx ptr idx (MOV(B|BZ|H|HZ|W|WZ)reg x) mem) => (MOVBstoreidx ptr idx x mem)
(MOVHstoreidx ptr idx (MOV(H|HZ|W|WZ)reg x) mem) => (MOVHstoreidx ptr idx x mem)
(MOVWstoreidx ptr idx (MOV(W|WZ)reg x) mem) => (MOVWstoreidx ptr idx x mem)
(MOVBstoreidx ptr idx (SRWconst (MOV(H|HZ)reg x) [c]) mem) && c <= 8 => (MOVBstoreidx ptr idx (SRWconst <typ.UInt32> x [c]) mem)
(MOVBstoreidx ptr idx (SRWconst (MOV(W|WZ)reg x) [c]) mem) && c <= 24 => (MOVBstoreidx ptr idx (SRWconst <typ.UInt32> x [c]) mem)
(MOVHBRstore ptr (MOV(H|HZ|W|WZ)reg x) mem) => (MOVHBRstore ptr x mem)
(MOVWBRstore ptr (MOV(W|WZ)reg x) mem) => (MOVWBRstore ptr x mem)

// Lose W-widening ops fed to compare-W
(CMP(W|WU) x (MOV(W|WZ)reg y)) => (CMP(W|WU) x y)
(CMP(W|WU) (MOV(W|WZ)reg x) y) => (CMP(W|WU) x y)

(CMP x (MOVDconst [c])) && is16Bit(c) => (CMPconst x [c])
(CMP (MOVDconst [c]) y) && is16Bit(c) => (InvertFlags (CMPconst y [c]))
(CMPW x (MOVDconst [c])) && is16Bit(c) => (CMPWconst x [int32(c)])
(CMPW (MOVDconst [c]) y) && is16Bit(c) => (InvertFlags (CMPWconst y [int32(c)]))

(CMPU x (MOVDconst [c])) && isU16Bit(c) => (CMPUconst x [c])
(CMPU (MOVDconst [c]) y) && isU16Bit(c) => (InvertFlags (CMPUconst y [c]))
(CMPWU x (MOVDconst [c])) && isU16Bit(c) => (CMPWUconst x [int32(c)])
(CMPWU (MOVDconst [c]) y) && isU16Bit(c) => (InvertFlags (CMPWUconst y [int32(c)]))

// Canonicalize the order of arguments to comparisons - helps with CSE.
((CMP|CMPW|CMPU|CMPWU) x y) && canonLessThan(x,y) => (InvertFlags ((CMP|CMPW|CMPU|CMPWU) y x))

// SETBC auxInt values 0=LT 1=GT 2=EQ   Crbit==1 ? 1 : 0
// SETBCR auxInt values 0=LT 1=GT 2=EQ   Crbit==1 ? 0 : 1
(Equal cmp) => (SETBC [2] cmp)
(NotEqual cmp) => (SETBCR [2] cmp)
(LessThan cmp) => (SETBC [0] cmp)
(FLessThan cmp) => (SETBC [0] cmp)
(FLessEqual cmp) => (OR (SETBC [2] cmp) (SETBC [0] cmp))
(GreaterEqual cmp) => (SETBCR [0] cmp)
(GreaterThan cmp)  => (SETBC [1] cmp)
(FGreaterEqual cmp) => (OR (SETBC [2] cmp) (SETBC [1] cmp))
(FGreaterThan cmp)  => (SETBC [1] cmp)
(LessEqual cmp) => (SETBCR [1] cmp)

(SETBC [0] (FlagLT)) => (MOVDconst [1])
(SETBC [0] (Flag(GT|EQ))) => (MOVDconst [0])
(SETBC [1] (FlagGT)) => (MOVDconst [1])
(SETBC [1] (Flag(LT|EQ))) => (MOVDconst [0])
(SETBC [2] (FlagEQ)) => (MOVDconst [1])
(SETBC [2] (Flag(LT|GT))) => (MOVDconst [0])

(SETBCR [0] (FlagLT)) => (MOVDconst [0])
(SETBCR [0] (Flag(GT|EQ))) => (MOVDconst [1])
(SETBCR [1] (FlagGT)) => (MOVDconst [0])
(SETBCR [1] (Flag(LT|EQ))) => (MOVDconst [1])
(SETBCR [2] (FlagEQ)) => (MOVDconst [0])
(SETBCR [2] (Flag(LT|GT))) => (MOVDconst [1])

(SETBC [0] (InvertFlags bool)) => (SETBC [1] bool)
(SETBC [1] (InvertFlags bool)) => (SETBC [0] bool)
(SETBC [2] (InvertFlags bool)) => (SETBC [2] bool)

(SETBCR [0] (InvertFlags bool)) => (SETBCR [1] bool)
(SETBCR [1] (InvertFlags bool)) => (SETBCR [0] bool)
(SETBCR [2] (InvertFlags bool)) => (SETBCR [2] bool)

// ISEL auxInt values 0=LT 1=GT 2=EQ   arg2 ? arg0 : arg1
// ISEL auxInt values 4=GE 5=LE 6=NE   !arg2 ? arg1 : arg0

(ISEL [2] x _ (FlagEQ)) => x
(ISEL [2] _ y (Flag(LT|GT))) => y

(ISEL [6] _ y (FlagEQ)) => y
(ISEL [6] x _ (Flag(LT|GT))) => x

(ISEL [0] _ y (Flag(EQ|GT))) => y
(ISEL [0] x _ (FlagLT)) => x

(ISEL [5] _ x (Flag(EQ|LT))) => x
(ISEL [5] y _ (FlagGT)) => y

(ISEL [1] _ y (Flag(EQ|LT))) => y
(ISEL [1] x _ (FlagGT)) => x

(ISEL [4] x _ (Flag(EQ|GT))) => x
(ISEL [4] _ y (FlagLT)) => y

(ISEL [2] x y ((CMP|CMPW)const [0] (Select0 (ANDCCconst [n] z)))) => (ISEL [2] x y (Select1 <types.TypeFlags> (ANDCCconst [n] z )))
(ISEL [6] x y ((CMP|CMPW)const [0] (Select0 (ANDCCconst [n] z)))) => (ISEL [6] x y (Select1 <types.TypeFlags> (ANDCCconst [n] z )))
(SETBC [n] (InvertFlags bool)) => (SETBCR [n] bool)
(SETBCR [n] (InvertFlags bool)) => (SETBC [n] bool)

(ISEL [n] x y (InvertFlags bool)) && n%4 == 0 => (ISEL [n+1] x y bool)
(ISEL [n] x y (InvertFlags bool)) && n%4 == 1 => (ISEL [n-1] x y bool)
(ISEL [n] x y (InvertFlags bool)) && n%4 == 2 => (ISEL [n] x y bool)
(XORconst [1] (SETBCR [n] cmp)) => (SETBC [n] cmp)
(XORconst [1] (SETBC [n] cmp)) => (SETBCR [n] cmp)

(SETBC [2] ((CMP|CMPW)const [0] (Select0 (ANDCCconst [1] z)))) => (XORconst [1] (Select0 <typ.UInt64> (ANDCCconst [1] z )))
(SETBCR [2] ((CMP|CMPW)const [0] (Select0 (ANDCCconst [1] z)))) => (Select0 <typ.UInt64> (ANDCCconst [1] z ))

(SETBC [2] (CMPWconst [0] (Select0 (ANDCCconst [n] z)))) => (SETBC [2] (Select1 <types.TypeFlags> (ANDCCconst [n] z )))
(SETBCR [2] (CMPWconst [0] (Select0 (ANDCCconst [n] z)))) => (SETBCR [2] (Select1 <types.TypeFlags> (ANDCCconst [n] z )))

// Only CMPconst for these in case AND|OR|XOR result is > 32 bits
(SETBC [2] (CMPconst [0] a:(AND y z))) && a.Uses == 1 => (SETBC [2] (Select1 <types.TypeFlags> (ANDCC y z )))
(SETBCR [2] (CMPconst [0] a:(AND y z))) && a.Uses == 1 => (SETBCR [2] (Select1 <types.TypeFlags> (ANDCC y z )))

(SETBC [2] (CMPconst [0] o:(OR y z))) && o.Uses == 1 => (SETBC [2] (Select1 <types.TypeFlags> (ORCC y z )))
(SETBCR [2] (CMPconst [0] o:(OR y z))) && o.Uses == 1 => (SETBCR [2] (Select1 <types.TypeFlags> (ORCC y z )))

(SETBC [2] (CMPconst [0] a:(XOR y z))) && a.Uses == 1 => (SETBC [2] (Select1 <types.TypeFlags> (XORCC y z )))
(SETBCR [2] (CMPconst [0] a:(XOR y z))) && a.Uses == 1 => (SETBCR [2] (Select1 <types.TypeFlags> (XORCC y z )))

// A particular pattern seen in cgo code:
(AND (MOVDconst [c]) x:(MOVBZload _ _)) => (Select0 (ANDCCconst [c&0xFF] x))

// floating point negative abs
(FNEG (F(ABS|NABS) x)) => (F(NABS|ABS) x)

// floating-point fused multiply-add/sub
(F(ADD|SUB) (FMUL x y) z) && x.Block.Func.useFMA(v) => (FM(ADD|SUB) x y z)
(F(ADDS|SUBS) (FMULS x y) z) && x.Block.Func.useFMA(v) => (FM(ADDS|SUBS) x y z)

// Arch-specific inlining for small or disjoint runtime.memmove
(SelectN [0] call:(CALLstatic {sym} s1:(MOVDstore _ (MOVDconst [sz]) s2:(MOVDstore  _ src s3:(MOVDstore {t} _ dst mem)))))
        && sz >= 0
        && isSameCall(sym, "runtime.memmove")
        && s1.Uses == 1 && s2.Uses == 1 && s3.Uses == 1
        && isInlinableMemmove(dst, src, sz, config)
        && clobber(s1, s2, s3, call)
        => (Move [sz] dst src mem)

// Match post-lowering calls, register version.
(SelectN [0] call:(CALLstatic {sym} dst src (MOVDconst [sz]) mem))
        && sz >= 0
        && isSameCall(sym, "runtime.memmove")
        && call.Uses == 1
        && isInlinableMemmove(dst, src, sz, config)
        && clobber(call)
        => (Move [sz] dst src mem)

// Prefetch instructions (TH specified using aux field)
// For DCBT Ra,Rb,TH, A value of TH indicates:
//     0, hint this cache line will be used soon. (PrefetchCache)
//     16, hint this cache line will not be used for long. (PrefetchCacheStreamed)
// See ISA 3.0 Book II 4.3.2 for more detail. https://openpower.foundation/specifications/isa/
(PrefetchCache ptr mem)          => (DCBT ptr mem [0])
(PrefetchCacheStreamed ptr mem)  => (DCBT ptr mem [16])

// Use byte reverse instructions on Power10
(Bswap(16|32|64) x) && buildcfg.GOPPC64>=10 => (BR(H|W|D) x)

// Fold bit reversal into loads.
(BR(W|H) x:(MOV(W|H)Zload [off] {sym} ptr mem)) && x.Uses == 1 => @x.Block (MOV(W|H)BRload (MOVDaddr <ptr.Type> [off] {sym} ptr) mem)
(BR(W|H) x:(MOV(W|H)Zloadidx ptr idx      mem)) && x.Uses == 1 => @x.Block (MOV(W|H)BRloadidx ptr idx mem)
(BRD x:(MOVDload [off] {sym} ptr mem)) && x.Uses == 1 => @x.Block (MOVDBRload (MOVDaddr <ptr.Type> [off] {sym} ptr) mem)
(BRD x:(MOVDloadidx ptr idx      mem)) && x.Uses == 1 => @x.Block (MOVDBRloadidx ptr idx mem)

// Fold bit reversal into stores.
(MOV(D|W|H)store [off] {sym} ptr r:(BR(D|W|H) val) mem) && r.Uses == 1 => (MOV(D|W|H)BRstore (MOVDaddr <ptr.Type> [off] {sym} ptr) val mem)
(MOV(D|W|H)storeidx ptr idx      r:(BR(D|W|H) val) mem) && r.Uses == 1 => (MOV(D|W|H)BRstoreidx ptr idx val mem)

// GOPPC64<10 rules.
// These Bswap operations should only be introduced by the memcombine pass in places where they can be folded into loads or stores.
(Bswap(32|16) x:(MOV(W|H)Zload [off] {sym} ptr mem)) => @x.Block (MOV(W|H)BRload (MOVDaddr <ptr.Type> [off] {sym} ptr) mem)
(Bswap(32|16) x:(MOV(W|H)Zloadidx ptr idx      mem)) => @x.Block (MOV(W|H)BRloadidx ptr idx mem)
(Bswap64 x:(MOVDload [off] {sym} ptr mem)) => @x.Block (MOVDBRload (MOVDaddr <ptr.Type> [off] {sym} ptr) mem)
(Bswap64 x:(MOVDloadidx ptr idx      mem)) => @x.Block (MOVDBRloadidx ptr idx mem)
(MOV(D|W|H)store [off] {sym} ptr (Bswap(64|32|16) val) mem) => (MOV(D|W|H)BRstore (MOVDaddr <ptr.Type> [off] {sym} ptr) val mem)
(MOV(D|W|H)storeidx ptr idx      (Bswap(64|32|16) val) mem) => (MOV(D|W|H)BRstoreidx ptr idx val mem)