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      1 // Copyright 2016 The Go Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style
      3 // license that can be found in the LICENSE file.
      4 
      5 // Lowering arithmetic
      6 (AddPtr x y) -> (ADDL  x y)
      7 (Add32  x y) -> (ADDL  x y)
      8 (Add16  x y) -> (ADDL  x y)
      9 (Add8   x y) -> (ADDL  x y)
     10 (Add32F x y) -> (ADDSS x y)
     11 (Add64F x y) -> (ADDSD x y)
     12 
     13 (Add32carry x y) -> (ADDLcarry x y)
     14 (Add32withcarry x y c) -> (ADCL x y c)
     15 
     16 (SubPtr x y) -> (SUBL  x y)
     17 (Sub32  x y) -> (SUBL  x y)
     18 (Sub16  x y) -> (SUBL  x y)
     19 (Sub8   x y) -> (SUBL  x y)
     20 (Sub32F x y) -> (SUBSS x y)
     21 (Sub64F x y) -> (SUBSD x y)
     22 
     23 (Sub32carry x y) -> (SUBLcarry x y)
     24 (Sub32withcarry x y c) -> (SBBL x y c)
     25 
     26 (Mul32  x y) -> (MULL  x y)
     27 (Mul16  x y) -> (MULL  x y)
     28 (Mul8   x y) -> (MULL  x y)
     29 (Mul32F x y) -> (MULSS x y)
     30 (Mul64F x y) -> (MULSD x y)
     31 
     32 (Mul32uhilo x y) -> (MULLQU x y)
     33 
     34 (Div32F x y) -> (DIVSS x y)
     35 (Div64F x y) -> (DIVSD x y)
     36 
     37 (Div32  x y) -> (DIVL  x y)
     38 (Div32u x y) -> (DIVLU x y)
     39 (Div16  x y) -> (DIVW  x y)
     40 (Div16u x y) -> (DIVWU x y)
     41 (Div8   x y) -> (DIVW  (SignExt8to16 x) (SignExt8to16 y))
     42 (Div8u  x y) -> (DIVWU (ZeroExt8to16 x) (ZeroExt8to16 y))
     43 
     44 (Hmul32  x y) -> (HMULL  x y)
     45 (Hmul32u x y) -> (HMULLU x y)
     46 (Hmul16  x y) -> (HMULW  x y)
     47 (Hmul16u x y) -> (HMULWU x y)
     48 (Hmul8   x y) -> (HMULB  x y)
     49 (Hmul8u  x y) -> (HMULBU x y)
     50 
     51 (Mod32  x y) -> (MODL  x y)
     52 (Mod32u x y) -> (MODLU x y)
     53 (Mod16  x y) -> (MODW  x y)
     54 (Mod16u x y) -> (MODWU x y)
     55 (Mod8   x y) -> (MODW  (SignExt8to16 x) (SignExt8to16 y))
     56 (Mod8u  x y) -> (MODWU (ZeroExt8to16 x) (ZeroExt8to16 y))
     57 
     58 (And32 x y) -> (ANDL x y)
     59 (And16 x y) -> (ANDL x y)
     60 (And8  x y) -> (ANDL x y)
     61 
     62 (Or32 x y) -> (ORL x y)
     63 (Or16 x y) -> (ORL x y)
     64 (Or8  x y) -> (ORL x y)
     65 
     66 (Xor32 x y) -> (XORL x y)
     67 (Xor16 x y) -> (XORL x y)
     68 (Xor8  x y) -> (XORL x y)
     69 
     70 (Neg32  x) -> (NEGL x)
     71 (Neg16  x) -> (NEGL x)
     72 (Neg8   x) -> (NEGL x)
     73 (Neg32F x) && !config.use387 -> (PXOR x (MOVSSconst <config.Frontend().TypeFloat32()> [f2i(math.Copysign(0, -1))]))
     74 (Neg64F x) && !config.use387 -> (PXOR x (MOVSDconst <config.Frontend().TypeFloat64()> [f2i(math.Copysign(0, -1))]))
     75 (Neg32F x) && config.use387 -> (FCHS x)
     76 (Neg64F x) && config.use387 -> (FCHS x)
     77 
     78 (Com32 x) -> (NOTL x)
     79 (Com16 x) -> (NOTL x)
     80 (Com8  x) -> (NOTL x)
     81 
     82 // Lowering boolean ops
     83 (AndB x y) -> (ANDL x y)
     84 (OrB x y) -> (ORL x y)
     85 (Not x) -> (XORLconst [1] x)
     86 
     87 // Lowering pointer arithmetic
     88 (OffPtr [off] ptr) -> (ADDLconst [off] ptr)
     89 
     90 (Bswap32 x) -> (BSWAPL x)
     91 
     92 (Sqrt x) -> (SQRTSD x)
     93 
     94 // Lowering extension
     95 (SignExt8to16  x) -> (MOVBLSX x)
     96 (SignExt8to32  x) -> (MOVBLSX x)
     97 (SignExt16to32 x) -> (MOVWLSX x)
     98 
     99 (ZeroExt8to16  x) -> (MOVBLZX x)
    100 (ZeroExt8to32  x) -> (MOVBLZX x)
    101 (ZeroExt16to32 x) -> (MOVWLZX x)
    102 
    103 (Signmask x) -> (SARLconst x [31])
    104 (Zeromask <t> x) -> (XORLconst [-1] (SBBLcarrymask <t> (CMPLconst x [1])))
    105 (Slicemask <t> x) -> (XORLconst [-1] (SARLconst <t> (SUBLconst <t> x [1]) [31]))
    106 
    107 // Lowering truncation
    108 // Because we ignore high parts of registers, truncates are just copies.
    109 (Trunc16to8  x) -> x
    110 (Trunc32to8  x) -> x
    111 (Trunc32to16 x) -> x
    112 
    113 // Lowering float <-> int
    114 (Cvt32to32F x) -> (CVTSL2SS x)
    115 (Cvt32to64F x) -> (CVTSL2SD x)
    116 
    117 (Cvt32Fto32 x) -> (CVTTSS2SL x)
    118 (Cvt64Fto32 x) -> (CVTTSD2SL x)
    119 
    120 (Cvt32Fto64F x) -> (CVTSS2SD x)
    121 (Cvt64Fto32F x) -> (CVTSD2SS x)
    122 
    123 // Lowering shifts
    124 // Unsigned shifts need to return 0 if shift amount is >= width of shifted value.
    125 //   result = (arg << shift) & (shift >= argbits ? 0 : 0xffffffffffffffff)
    126 (Lsh32x32 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPLconst y [32])))
    127 (Lsh32x16 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPWconst y [32])))
    128 (Lsh32x8  <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPBconst y [32])))
    129 
    130 (Lsh16x32 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPLconst y [32])))
    131 (Lsh16x16 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPWconst y [32])))
    132 (Lsh16x8  <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPBconst y [32])))
    133 
    134 (Lsh8x32 <t> x y)  -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPLconst y [32])))
    135 (Lsh8x16 <t> x y)  -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPWconst y [32])))
    136 (Lsh8x8  <t> x y)  -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPBconst y [32])))
    137 
    138 (Lrot32 <t> x [c]) -> (ROLLconst <t> [c&31] x)
    139 (Lrot16 <t> x [c]) -> (ROLWconst <t> [c&15] x)
    140 (Lrot8  <t> x [c]) -> (ROLBconst <t> [c&7] x)
    141 
    142 (Rsh32Ux32 <t> x y) -> (ANDL (SHRL <t> x y) (SBBLcarrymask <t> (CMPLconst y [32])))
    143 (Rsh32Ux16 <t> x y) -> (ANDL (SHRL <t> x y) (SBBLcarrymask <t> (CMPWconst y [32])))
    144 (Rsh32Ux8  <t> x y) -> (ANDL (SHRL <t> x y) (SBBLcarrymask <t> (CMPBconst y [32])))
    145 
    146 (Rsh16Ux32 <t> x y) -> (ANDL (SHRW <t> x y) (SBBLcarrymask <t> (CMPLconst y [16])))
    147 (Rsh16Ux16 <t> x y) -> (ANDL (SHRW <t> x y) (SBBLcarrymask <t> (CMPWconst y [16])))
    148 (Rsh16Ux8  <t> x y) -> (ANDL (SHRW <t> x y) (SBBLcarrymask <t> (CMPBconst y [16])))
    149 
    150 (Rsh8Ux32 <t> x y)  -> (ANDL (SHRB <t> x y) (SBBLcarrymask <t> (CMPLconst y [8])))
    151 (Rsh8Ux16 <t> x y)  -> (ANDL (SHRB <t> x y) (SBBLcarrymask <t> (CMPWconst y [8])))
    152 (Rsh8Ux8  <t> x y)  -> (ANDL (SHRB <t> x y) (SBBLcarrymask <t> (CMPBconst y [8])))
    153 
    154 // Signed right shift needs to return 0/-1 if shift amount is >= width of shifted value.
    155 // We implement this by setting the shift value to -1 (all ones) if the shift value is >= width.
    156 
    157 (Rsh32x32 <t> x y) -> (SARL <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPLconst y [32])))))
    158 (Rsh32x16 <t> x y) -> (SARL <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPWconst y [32])))))
    159 (Rsh32x8  <t> x y) -> (SARL <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPBconst y [32])))))
    160 
    161 (Rsh16x32 <t> x y) -> (SARW <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPLconst y [16])))))
    162 (Rsh16x16 <t> x y) -> (SARW <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPWconst y [16])))))
    163 (Rsh16x8  <t> x y) -> (SARW <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPBconst y [16])))))
    164 
    165 (Rsh8x32 <t> x y)  -> (SARB <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPLconst y [8])))))
    166 (Rsh8x16 <t> x y)  -> (SARB <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPWconst y [8])))))
    167 (Rsh8x8  <t> x y)  -> (SARB <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPBconst y [8])))))
    168 
    169 // constant shifts
    170 // generic opt rewrites all constant shifts to shift by Const64
    171 (Lsh32x64 x (Const64 [c])) && uint64(c) < 32 -> (SHLLconst x [c])
    172 (Rsh32x64 x (Const64 [c])) && uint64(c) < 32 -> (SARLconst x [c])
    173 (Rsh32Ux64 x (Const64 [c])) && uint64(c) < 32 -> (SHRLconst x [c])
    174 (Lsh16x64 x (Const64 [c])) && uint64(c) < 16 -> (SHLLconst x [c])
    175 (Rsh16x64 x (Const64 [c])) && uint64(c) < 16 -> (SARWconst x [c])
    176 (Rsh16Ux64 x (Const64 [c])) && uint64(c) < 16 -> (SHRWconst x [c])
    177 (Lsh8x64 x (Const64 [c])) && uint64(c) < 8 -> (SHLLconst x [c])
    178 (Rsh8x64 x (Const64 [c])) && uint64(c) < 8 -> (SARBconst x [c])
    179 (Rsh8Ux64 x (Const64 [c])) && uint64(c) < 8 -> (SHRBconst x [c])
    180 
    181 // large constant shifts
    182 (Lsh32x64 _ (Const64 [c])) && uint64(c) >= 32 -> (Const32 [0])
    183 (Rsh32Ux64 _ (Const64 [c])) && uint64(c) >= 32 -> (Const32 [0])
    184 (Lsh16x64 _ (Const64 [c])) && uint64(c) >= 16 -> (Const16 [0])
    185 (Rsh16Ux64 _ (Const64 [c])) && uint64(c) >= 16 -> (Const16 [0])
    186 (Lsh8x64 _ (Const64 [c])) && uint64(c) >= 8 -> (Const8 [0])
    187 (Rsh8Ux64 _ (Const64 [c])) && uint64(c) >= 8 -> (Const8 [0])
    188 
    189 // large constant signed right shift, we leave the sign bit
    190 (Rsh32x64 x (Const64 [c])) && uint64(c) >= 32 -> (SARLconst x [31])
    191 (Rsh16x64 x (Const64 [c])) && uint64(c) >= 16 -> (SARWconst x [15])
    192 (Rsh8x64 x (Const64 [c])) && uint64(c) >= 8 -> (SARBconst x [7])
    193 
    194 // Lowering comparisons
    195 (Less32  x y) -> (SETL (CMPL x y))
    196 (Less16  x y) -> (SETL (CMPW x y))
    197 (Less8   x y) -> (SETL (CMPB x y))
    198 (Less32U x y) -> (SETB (CMPL x y))
    199 (Less16U x y) -> (SETB (CMPW x y))
    200 (Less8U  x y) -> (SETB (CMPB x y))
    201 // Use SETGF with reversed operands to dodge NaN case
    202 (Less64F x y) -> (SETGF (UCOMISD y x))
    203 (Less32F x y) -> (SETGF (UCOMISS y x))
    204 
    205 (Leq32  x y) -> (SETLE (CMPL x y))
    206 (Leq16  x y) -> (SETLE (CMPW x y))
    207 (Leq8   x y) -> (SETLE (CMPB x y))
    208 (Leq32U x y) -> (SETBE (CMPL x y))
    209 (Leq16U x y) -> (SETBE (CMPW x y))
    210 (Leq8U  x y) -> (SETBE (CMPB x y))
    211 // Use SETGEF with reversed operands to dodge NaN case
    212 (Leq64F x y) -> (SETGEF (UCOMISD y x))
    213 (Leq32F x y) -> (SETGEF (UCOMISS y x))
    214 
    215 (Greater32  x y) -> (SETG (CMPL x y))
    216 (Greater16  x y) -> (SETG (CMPW x y))
    217 (Greater8   x y) -> (SETG (CMPB x y))
    218 (Greater32U x y) -> (SETA (CMPL x y))
    219 (Greater16U x y) -> (SETA (CMPW x y))
    220 (Greater8U  x y) -> (SETA (CMPB x y))
    221 // Note Go assembler gets UCOMISx operand order wrong, but it is right here
    222 // Bug is accommodated at generation of assembly language.
    223 (Greater64F x y) -> (SETGF (UCOMISD x y))
    224 (Greater32F x y) -> (SETGF (UCOMISS x y))
    225 
    226 (Geq32  x y) -> (SETGE (CMPL x y))
    227 (Geq16  x y) -> (SETGE (CMPW x y))
    228 (Geq8   x y) -> (SETGE (CMPB x y))
    229 (Geq32U x y) -> (SETAE (CMPL x y))
    230 (Geq16U x y) -> (SETAE (CMPW x y))
    231 (Geq8U  x y) -> (SETAE (CMPB x y))
    232 // Note Go assembler gets UCOMISx operand order wrong, but it is right here
    233 // Bug is accommodated at generation of assembly language.
    234 (Geq64F x y) -> (SETGEF (UCOMISD x y))
    235 (Geq32F x y) -> (SETGEF (UCOMISS x y))
    236 
    237 (Eq32  x y) -> (SETEQ (CMPL x y))
    238 (Eq16  x y) -> (SETEQ (CMPW x y))
    239 (Eq8   x y) -> (SETEQ (CMPB x y))
    240 (EqB   x y) -> (SETEQ (CMPB x y))
    241 (EqPtr x y) -> (SETEQ (CMPL x y))
    242 (Eq64F x y) -> (SETEQF (UCOMISD x y))
    243 (Eq32F x y) -> (SETEQF (UCOMISS x y))
    244 
    245 (Neq32  x y) -> (SETNE (CMPL x y))
    246 (Neq16  x y) -> (SETNE (CMPW x y))
    247 (Neq8   x y) -> (SETNE (CMPB x y))
    248 (NeqB   x y) -> (SETNE (CMPB x y))
    249 (NeqPtr x y) -> (SETNE (CMPL x y))
    250 (Neq64F x y) -> (SETNEF (UCOMISD x y))
    251 (Neq32F x y) -> (SETNEF (UCOMISS x y))
    252 
    253 // Lowering loads
    254 (Load <t> ptr mem) && (is32BitInt(t) || isPtr(t)) -> (MOVLload ptr mem)
    255 (Load <t> ptr mem) && is16BitInt(t) -> (MOVWload ptr mem)
    256 (Load <t> ptr mem) && (t.IsBoolean() || is8BitInt(t)) -> (MOVBload ptr mem)
    257 (Load <t> ptr mem) && is32BitFloat(t) -> (MOVSSload ptr mem)
    258 (Load <t> ptr mem) && is64BitFloat(t) -> (MOVSDload ptr mem)
    259 
    260 // Lowering stores
    261 // These more-specific FP versions of Store pattern should come first.
    262 (Store [8] ptr val mem) && is64BitFloat(val.Type) -> (MOVSDstore ptr val mem)
    263 (Store [4] ptr val mem) && is32BitFloat(val.Type) -> (MOVSSstore ptr val mem)
    264 
    265 (Store [4] ptr val mem) -> (MOVLstore ptr val mem)
    266 (Store [2] ptr val mem) -> (MOVWstore ptr val mem)
    267 (Store [1] ptr val mem) -> (MOVBstore ptr val mem)
    268 
    269 // Lowering moves
    270 (Move [s] _ _ mem) && SizeAndAlign(s).Size() == 0 -> mem
    271 (Move [s] dst src mem) && SizeAndAlign(s).Size() == 1 -> (MOVBstore dst (MOVBload src mem) mem)
    272 (Move [s] dst src mem) && SizeAndAlign(s).Size() == 2 -> (MOVWstore dst (MOVWload src mem) mem)
    273 (Move [s] dst src mem) && SizeAndAlign(s).Size() == 4 -> (MOVLstore dst (MOVLload src mem) mem)
    274 (Move [s] dst src mem) && SizeAndAlign(s).Size() == 3 ->
    275 	(MOVBstore [2] dst (MOVBload [2] src mem)
    276 		(MOVWstore dst (MOVWload src mem) mem))
    277 (Move [s] dst src mem) && SizeAndAlign(s).Size() == 5 ->
    278 	(MOVBstore [4] dst (MOVBload [4] src mem)
    279 		(MOVLstore dst (MOVLload src mem) mem))
    280 (Move [s] dst src mem) && SizeAndAlign(s).Size() == 6 ->
    281 	(MOVWstore [4] dst (MOVWload [4] src mem)
    282 		(MOVLstore dst (MOVLload src mem) mem))
    283 (Move [s] dst src mem) && SizeAndAlign(s).Size() == 7 ->
    284 	(MOVLstore [3] dst (MOVLload [3] src mem)
    285 		(MOVLstore dst (MOVLload src mem) mem))
    286 (Move [s] dst src mem) && SizeAndAlign(s).Size() == 8 ->
    287 	(MOVLstore [4] dst (MOVLload [4] src mem)
    288 		(MOVLstore dst (MOVLload src mem) mem))
    289 
    290 // Adjust moves to be a multiple of 4 bytes.
    291 (Move [s] dst src mem)
    292 	&& SizeAndAlign(s).Size() > 8 && SizeAndAlign(s).Size()%4 != 0 ->
    293 	(Move [SizeAndAlign(s).Size()-SizeAndAlign(s).Size()%4]
    294 		(ADDLconst <dst.Type> dst [SizeAndAlign(s).Size()%4])
    295 		(ADDLconst <src.Type> src [SizeAndAlign(s).Size()%4])
    296 		(MOVLstore dst (MOVLload src mem) mem))
    297 
    298 // Medium copying uses a duff device.
    299 (Move [s] dst src mem)
    300 	&& SizeAndAlign(s).Size() > 8 && SizeAndAlign(s).Size() <= 4*128 && SizeAndAlign(s).Size()%4 == 0
    301 	&& !config.noDuffDevice ->
    302 	(DUFFCOPY [10*(128-SizeAndAlign(s).Size()/4)] dst src mem)
    303 // 10 and 128 are magic constants.  10 is the number of bytes to encode:
    304 //	MOVL	(SI), CX
    305 //	ADDL	$4, SI
    306 //	MOVL	CX, (DI)
    307 //	ADDL	$4, DI
    308 // and 128 is the number of such blocks. See src/runtime/duff_386.s:duffcopy.
    309 
    310 // Large copying uses REP MOVSL.
    311 (Move [s] dst src mem) && (SizeAndAlign(s).Size() > 4*128 || config.noDuffDevice) && SizeAndAlign(s).Size()%4 == 0 ->
    312 	(REPMOVSL dst src (MOVLconst [SizeAndAlign(s).Size()/4]) mem)
    313 
    314 // Lowering Zero instructions
    315 (Zero [s] _ mem) && SizeAndAlign(s).Size() == 0 -> mem
    316 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 1 -> (MOVBstoreconst [0] destptr mem)
    317 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 2 -> (MOVWstoreconst [0] destptr mem)
    318 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 4 -> (MOVLstoreconst [0] destptr mem)
    319 
    320 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 3 ->
    321 	(MOVBstoreconst [makeValAndOff(0,2)] destptr
    322 		(MOVWstoreconst [0] destptr mem))
    323 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 5 ->
    324 	(MOVBstoreconst [makeValAndOff(0,4)] destptr
    325 		(MOVLstoreconst [0] destptr mem))
    326 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 6 ->
    327 	(MOVWstoreconst [makeValAndOff(0,4)] destptr
    328 		(MOVLstoreconst [0] destptr mem))
    329 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 7 ->
    330 	(MOVLstoreconst [makeValAndOff(0,3)] destptr
    331 		(MOVLstoreconst [0] destptr mem))
    332 
    333 // Strip off any fractional word zeroing.
    334 (Zero [s] destptr mem) && SizeAndAlign(s).Size()%4 != 0 && SizeAndAlign(s).Size() > 4 ->
    335 	(Zero [SizeAndAlign(s).Size()-SizeAndAlign(s).Size()%4] (ADDLconst destptr [SizeAndAlign(s).Size()%4])
    336 		(MOVLstoreconst [0] destptr mem))
    337 
    338 // Zero small numbers of words directly.
    339 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 8 ->
    340 	(MOVLstoreconst [makeValAndOff(0,4)] destptr
    341 		(MOVLstoreconst [0] destptr mem))
    342 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 12 ->
    343 	(MOVLstoreconst [makeValAndOff(0,8)] destptr
    344 		(MOVLstoreconst [makeValAndOff(0,4)] destptr
    345 			(MOVLstoreconst [0] destptr mem)))
    346 (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 16 ->
    347 	(MOVLstoreconst [makeValAndOff(0,12)] destptr
    348 		(MOVLstoreconst [makeValAndOff(0,8)] destptr
    349 			(MOVLstoreconst [makeValAndOff(0,4)] destptr
    350 				(MOVLstoreconst [0] destptr mem))))
    351 
    352 // Medium zeroing uses a duff device.
    353 (Zero [s] destptr mem)
    354   && SizeAndAlign(s).Size() > 16
    355   && SizeAndAlign(s).Size() <= 4*128
    356   && SizeAndAlign(s).Size()%4 == 0
    357   && !config.noDuffDevice ->
    358 	(DUFFZERO [1*(128-SizeAndAlign(s).Size()/4)] destptr (MOVLconst [0]) mem)
    359 // 1 and 128 are magic constants.  1 is the number of bytes to encode STOSL.
    360 // 128 is the number of STOSL instructions in duffzero.
    361 // See src/runtime/duff_386.s:duffzero.
    362 
    363 // Large zeroing uses REP STOSQ.
    364 (Zero [s] destptr mem)
    365   && (SizeAndAlign(s).Size() > 4*128 || (config.noDuffDevice && SizeAndAlign(s).Size() > 16))
    366   && SizeAndAlign(s).Size()%4 == 0 ->
    367 	(REPSTOSL destptr (MOVLconst [SizeAndAlign(s).Size()/4]) (MOVLconst [0]) mem)
    368 
    369 // Lowering constants
    370 (Const8   [val]) -> (MOVLconst [val])
    371 (Const16  [val]) -> (MOVLconst [val])
    372 (Const32  [val]) -> (MOVLconst [val])
    373 (Const32F [val]) -> (MOVSSconst [val])
    374 (Const64F [val]) -> (MOVSDconst [val])
    375 (ConstNil) -> (MOVLconst [0])
    376 (ConstBool [b]) -> (MOVLconst [b])
    377 
    378 // Lowering calls
    379 (StaticCall [argwid] {target} mem) -> (CALLstatic [argwid] {target} mem)
    380 (ClosureCall [argwid] entry closure mem) -> (CALLclosure [argwid] entry closure mem)
    381 (DeferCall [argwid] mem) -> (CALLdefer [argwid] mem)
    382 (GoCall [argwid] mem) -> (CALLgo [argwid] mem)
    383 (InterCall [argwid] entry mem) -> (CALLinter [argwid] entry mem)
    384 
    385 // Miscellaneous
    386 (Convert <t> x mem) -> (MOVLconvert <t> x mem)
    387 (IsNonNil p) -> (SETNE (TESTL p p))
    388 (IsInBounds idx len) -> (SETB (CMPL idx len))
    389 (IsSliceInBounds idx len) -> (SETBE (CMPL idx len))
    390 (NilCheck ptr mem) -> (LoweredNilCheck ptr mem)
    391 (GetG mem) -> (LoweredGetG mem)
    392 (GetClosurePtr) -> (LoweredGetClosurePtr)
    393 (Addr {sym} base) -> (LEAL {sym} base)
    394 
    395 // block rewrites
    396 (If (SETL  cmp) yes no) -> (LT  cmp yes no)
    397 (If (SETLE cmp) yes no) -> (LE  cmp yes no)
    398 (If (SETG  cmp) yes no) -> (GT  cmp yes no)
    399 (If (SETGE cmp) yes no) -> (GE  cmp yes no)
    400 (If (SETEQ cmp) yes no) -> (EQ  cmp yes no)
    401 (If (SETNE cmp) yes no) -> (NE  cmp yes no)
    402 (If (SETB  cmp) yes no) -> (ULT cmp yes no)
    403 (If (SETBE cmp) yes no) -> (ULE cmp yes no)
    404 (If (SETA  cmp) yes no) -> (UGT cmp yes no)
    405 (If (SETAE cmp) yes no) -> (UGE cmp yes no)
    406 
    407 // Special case for floating point - LF/LEF not generated
    408 (If (SETGF  cmp) yes no) -> (UGT  cmp yes no)
    409 (If (SETGEF cmp) yes no) -> (UGE  cmp yes no)
    410 (If (SETEQF cmp) yes no) -> (EQF  cmp yes no)
    411 (If (SETNEF cmp) yes no) -> (NEF  cmp yes no)
    412 
    413 (If cond yes no) -> (NE (TESTB cond cond) yes no)
    414 
    415 // ***************************
    416 // Above: lowering rules
    417 // Below: optimizations
    418 // ***************************
    419 // TODO: Should the optimizations be a separate pass?
    420 
    421 // Fold boolean tests into blocks
    422 (NE (TESTB (SETL  cmp) (SETL  cmp)) yes no) -> (LT  cmp yes no)
    423 (NE (TESTB (SETLE cmp) (SETLE cmp)) yes no) -> (LE  cmp yes no)
    424 (NE (TESTB (SETG  cmp) (SETG  cmp)) yes no) -> (GT  cmp yes no)
    425 (NE (TESTB (SETGE cmp) (SETGE cmp)) yes no) -> (GE  cmp yes no)
    426 (NE (TESTB (SETEQ cmp) (SETEQ cmp)) yes no) -> (EQ  cmp yes no)
    427 (NE (TESTB (SETNE cmp) (SETNE cmp)) yes no) -> (NE  cmp yes no)
    428 (NE (TESTB (SETB  cmp) (SETB  cmp)) yes no) -> (ULT cmp yes no)
    429 (NE (TESTB (SETBE cmp) (SETBE cmp)) yes no) -> (ULE cmp yes no)
    430 (NE (TESTB (SETA  cmp) (SETA  cmp)) yes no) -> (UGT cmp yes no)
    431 (NE (TESTB (SETAE cmp) (SETAE cmp)) yes no) -> (UGE cmp yes no)
    432 
    433 // Special case for floating point - LF/LEF not generated
    434 (NE (TESTB (SETGF  cmp) (SETGF  cmp)) yes no) -> (UGT  cmp yes no)
    435 (NE (TESTB (SETGEF cmp) (SETGEF cmp)) yes no) -> (UGE  cmp yes no)
    436 (NE (TESTB (SETEQF cmp) (SETEQF cmp)) yes no) -> (EQF  cmp yes no)
    437 (NE (TESTB (SETNEF cmp) (SETNEF cmp)) yes no) -> (NEF  cmp yes no)
    438 
    439 // fold constants into instructions
    440 (ADDL x (MOVLconst [c])) -> (ADDLconst [c] x)
    441 (ADDL (MOVLconst [c]) x) -> (ADDLconst [c] x)
    442 (ADDLcarry x (MOVLconst [c])) -> (ADDLconstcarry [c] x)
    443 (ADDLcarry (MOVLconst [c]) x) -> (ADDLconstcarry [c] x)
    444 (ADCL x (MOVLconst [c]) f) -> (ADCLconst [c] x f)
    445 (ADCL (MOVLconst [c]) x f) -> (ADCLconst [c] x f)
    446 
    447 (SUBL x (MOVLconst [c])) -> (SUBLconst x [c])
    448 (SUBL (MOVLconst [c]) x) -> (NEGL (SUBLconst <v.Type> x [c]))
    449 (SUBLcarry x (MOVLconst [c])) -> (SUBLconstcarry [c] x)
    450 (SBBL x (MOVLconst [c]) f) -> (SBBLconst [c] x f)
    451 
    452 (MULL x (MOVLconst [c])) -> (MULLconst [c] x)
    453 (MULL (MOVLconst [c]) x) -> (MULLconst [c] x)
    454 
    455 (ANDL x (MOVLconst [c])) -> (ANDLconst [c] x)
    456 (ANDL (MOVLconst [c]) x) -> (ANDLconst [c] x)
    457 
    458 (ANDLconst [c] (ANDLconst [d] x)) -> (ANDLconst [c & d] x)
    459 
    460 (XORLconst [c] (XORLconst [d] x)) -> (XORLconst [c ^ d] x)
    461 
    462 (MULLconst [c] (MULLconst [d] x)) -> (MULLconst [int64(int32(c * d))] x)
    463 
    464 (ORL x (MOVLconst [c])) -> (ORLconst [c] x)
    465 (ORL (MOVLconst [c]) x) -> (ORLconst [c] x)
    466 
    467 (XORL x (MOVLconst [c])) -> (XORLconst [c] x)
    468 (XORL (MOVLconst [c]) x) -> (XORLconst [c] x)
    469 
    470 (SHLL x (MOVLconst [c])) -> (SHLLconst [c&31] x)
    471 (SHLL x (MOVLconst [c])) -> (SHLLconst [c&31] x)
    472 
    473 (SHRL x (MOVLconst [c])) -> (SHRLconst [c&31] x)
    474 (SHRL x (MOVLconst [c])) -> (SHRLconst [c&31] x)
    475 
    476 (SHRW x (MOVLconst [c])) -> (SHRWconst [c&31] x)
    477 (SHRW x (MOVLconst [c])) -> (SHRWconst [c&31] x)
    478 
    479 (SHRB x (MOVLconst [c])) -> (SHRBconst [c&31] x)
    480 (SHRB x (MOVLconst [c])) -> (SHRBconst [c&31] x)
    481 
    482 (SARL x (MOVLconst [c])) -> (SARLconst [c&31] x)
    483 (SARL x (MOVLconst [c])) -> (SARLconst [c&31] x)
    484 
    485 (SARW x (MOVLconst [c])) -> (SARWconst [c&31] x)
    486 (SARW x (MOVLconst [c])) -> (SARWconst [c&31] x)
    487 
    488 (SARB x (MOVLconst [c])) -> (SARBconst [c&31] x)
    489 (SARB x (MOVLconst [c])) -> (SARBconst [c&31] x)
    490 
    491 (SARL x (ANDLconst [31] y)) -> (SARL x y)
    492 
    493 (SHLL x (ANDLconst [31] y)) -> (SHLL x y)
    494 
    495 (SHRL x (ANDLconst [31] y)) -> (SHRL x y)
    496 
    497 (ROLLconst [c] (ROLLconst [d] x)) -> (ROLLconst [(c+d)&31] x)
    498 (ROLWconst [c] (ROLWconst [d] x)) -> (ROLWconst [(c+d)&15] x)
    499 (ROLBconst [c] (ROLBconst [d] x)) -> (ROLBconst [(c+d)& 7] x)
    500 
    501 (ROLLconst [0] x) -> x
    502 (ROLWconst [0] x) -> x
    503 (ROLBconst [0] x) -> x
    504 
    505 // Note: the word and byte shifts keep the low 5 bits (not the low 4 or 3 bits)
    506 // because the x86 instructions are defined to use all 5 bits of the shift even
    507 // for the small shifts. I don't think we'll ever generate a weird shift (e.g.
    508 // (SHRW x (MOVLconst [24])), but just in case.
    509 
    510 (CMPL x (MOVLconst [c])) -> (CMPLconst x [c])
    511 (CMPL (MOVLconst [c]) x) -> (InvertFlags (CMPLconst x [c]))
    512 (CMPW x (MOVLconst [c])) -> (CMPWconst x [int64(int16(c))])
    513 (CMPW (MOVLconst [c]) x) -> (InvertFlags (CMPWconst x [int64(int16(c))]))
    514 (CMPB x (MOVLconst [c])) -> (CMPBconst x [int64(int8(c))])
    515 (CMPB (MOVLconst [c]) x) -> (InvertFlags (CMPBconst x [int64(int8(c))]))
    516 
    517 // strength reduction
    518 // Assumes that the following costs from https://gmplib.org/~tege/x86-timing.pdf:
    519 //    1 - addq, shlq, leaq, negq
    520 //    3 - imulq
    521 // This limits the rewrites to two instructions.
    522 // TODO: 27, 81
    523 (MULLconst [-1] x) -> (NEGL x)
    524 (MULLconst [0] _) -> (MOVLconst [0])
    525 (MULLconst [1] x) -> x
    526 (MULLconst [3] x) -> (LEAL2 x x)
    527 (MULLconst [5] x) -> (LEAL4 x x)
    528 (MULLconst [7] x) -> (LEAL8 (NEGL <v.Type> x) x)
    529 (MULLconst [9] x) -> (LEAL8 x x)
    530 (MULLconst [11] x) -> (LEAL2 x (LEAL4 <v.Type> x x))
    531 (MULLconst [13] x) -> (LEAL4 x (LEAL2 <v.Type> x x))
    532 (MULLconst [21] x) -> (LEAL4 x (LEAL4 <v.Type> x x))
    533 (MULLconst [25] x) -> (LEAL8 x (LEAL2 <v.Type> x x))
    534 (MULLconst [37] x) -> (LEAL4 x (LEAL8 <v.Type> x x))
    535 (MULLconst [41] x) -> (LEAL8 x (LEAL4 <v.Type> x x))
    536 (MULLconst [73] x) -> (LEAL8 x (LEAL8 <v.Type> x x))
    537 
    538 (MULLconst [c] x) && isPowerOfTwo(c) -> (SHLLconst [log2(c)] x)
    539 (MULLconst [c] x) && isPowerOfTwo(c+1) && c >= 15 -> (SUBL (SHLLconst <v.Type> [log2(c+1)] x) x)
    540 (MULLconst [c] x) && isPowerOfTwo(c-1) && c >= 17 -> (LEAL1 (SHLLconst <v.Type> [log2(c-1)] x) x)
    541 (MULLconst [c] x) && isPowerOfTwo(c-2) && c >= 34 -> (LEAL2 (SHLLconst <v.Type> [log2(c-2)] x) x)
    542 (MULLconst [c] x) && isPowerOfTwo(c-4) && c >= 68 -> (LEAL4 (SHLLconst <v.Type> [log2(c-4)] x) x)
    543 (MULLconst [c] x) && isPowerOfTwo(c-8) && c >= 136 -> (LEAL8 (SHLLconst <v.Type> [log2(c-8)] x) x)
    544 (MULLconst [c] x) && c%3 == 0 && isPowerOfTwo(c/3)-> (SHLLconst [log2(c/3)] (LEAL2 <v.Type> x x))
    545 (MULLconst [c] x) && c%5 == 0 && isPowerOfTwo(c/5)-> (SHLLconst [log2(c/5)] (LEAL4 <v.Type> x x))
    546 (MULLconst [c] x) && c%9 == 0 && isPowerOfTwo(c/9)-> (SHLLconst [log2(c/9)] (LEAL8 <v.Type> x x))
    547 
    548 // combine add/shift into LEAL
    549 (ADDL x (SHLLconst [3] y)) -> (LEAL8 x y)
    550 (ADDL x (SHLLconst [2] y)) -> (LEAL4 x y)
    551 (ADDL x (SHLLconst [1] y)) -> (LEAL2 x y)
    552 (ADDL x (ADDL y y)) -> (LEAL2 x y)
    553 (ADDL x (ADDL x y)) -> (LEAL2 y x)
    554 (ADDL x (ADDL y x)) -> (LEAL2 y x)
    555 
    556 // combine ADDL/ADDLconst into LEAL1
    557 (ADDLconst [c] (ADDL x y)) -> (LEAL1 [c] x y)
    558 (ADDL (ADDLconst [c] x) y) -> (LEAL1 [c] x y)
    559 (ADDL x (ADDLconst [c] y)) -> (LEAL1 [c] x y)
    560 
    561 // fold ADDL into LEAL
    562 (ADDLconst [c] (LEAL [d] {s} x)) && is32Bit(c+d) -> (LEAL [c+d] {s} x)
    563 (LEAL [c] {s} (ADDLconst [d] x)) && is32Bit(c+d) -> (LEAL [c+d] {s} x)
    564 (LEAL [c] {s} (ADDL x y)) && x.Op != OpSB && y.Op != OpSB -> (LEAL1 [c] {s} x y)
    565 (ADDL x (LEAL [c] {s} y)) && x.Op != OpSB && y.Op != OpSB -> (LEAL1 [c] {s} x y)
    566 (ADDL (LEAL [c] {s} x) y) && x.Op != OpSB && y.Op != OpSB -> (LEAL1 [c] {s} x y)
    567 
    568 // fold ADDLconst into LEALx
    569 (ADDLconst [c] (LEAL1 [d] {s} x y)) && is32Bit(c+d) -> (LEAL1 [c+d] {s} x y)
    570 (ADDLconst [c] (LEAL2 [d] {s} x y)) && is32Bit(c+d) -> (LEAL2 [c+d] {s} x y)
    571 (ADDLconst [c] (LEAL4 [d] {s} x y)) && is32Bit(c+d) -> (LEAL4 [c+d] {s} x y)
    572 (ADDLconst [c] (LEAL8 [d] {s} x y)) && is32Bit(c+d) -> (LEAL8 [c+d] {s} x y)
    573 (LEAL1 [c] {s} (ADDLconst [d] x) y) && is32Bit(c+d)   && x.Op != OpSB -> (LEAL1 [c+d] {s} x y)
    574 (LEAL1 [c] {s} x (ADDLconst [d] y)) && is32Bit(c+d)   && y.Op != OpSB -> (LEAL1 [c+d] {s} x y)
    575 (LEAL2 [c] {s} (ADDLconst [d] x) y) && is32Bit(c+d)   && x.Op != OpSB -> (LEAL2 [c+d] {s} x y)
    576 (LEAL2 [c] {s} x (ADDLconst [d] y)) && is32Bit(c+2*d) && y.Op != OpSB -> (LEAL2 [c+2*d] {s} x y)
    577 (LEAL4 [c] {s} (ADDLconst [d] x) y) && is32Bit(c+d)   && x.Op != OpSB -> (LEAL4 [c+d] {s} x y)
    578 (LEAL4 [c] {s} x (ADDLconst [d] y)) && is32Bit(c+4*d) && y.Op != OpSB -> (LEAL4 [c+4*d] {s} x y)
    579 (LEAL8 [c] {s} (ADDLconst [d] x) y) && is32Bit(c+d)   && x.Op != OpSB -> (LEAL8 [c+d] {s} x y)
    580 (LEAL8 [c] {s} x (ADDLconst [d] y)) && is32Bit(c+8*d) && y.Op != OpSB -> (LEAL8 [c+8*d] {s} x y)
    581 
    582 // fold shifts into LEALx
    583 (LEAL1 [c] {s} x (SHLLconst [1] y)) -> (LEAL2 [c] {s} x y)
    584 (LEAL1 [c] {s} (SHLLconst [1] x) y) -> (LEAL2 [c] {s} y x)
    585 (LEAL1 [c] {s} x (SHLLconst [2] y)) -> (LEAL4 [c] {s} x y)
    586 (LEAL1 [c] {s} (SHLLconst [2] x) y) -> (LEAL4 [c] {s} y x)
    587 (LEAL1 [c] {s} x (SHLLconst [3] y)) -> (LEAL8 [c] {s} x y)
    588 (LEAL1 [c] {s} (SHLLconst [3] x) y) -> (LEAL8 [c] {s} y x)
    589 
    590 (LEAL2 [c] {s} x (SHLLconst [1] y)) -> (LEAL4 [c] {s} x y)
    591 (LEAL2 [c] {s} x (SHLLconst [2] y)) -> (LEAL8 [c] {s} x y)
    592 (LEAL4 [c] {s} x (SHLLconst [1] y)) -> (LEAL8 [c] {s} x y)
    593 
    594 // reverse ordering of compare instruction
    595 (SETL (InvertFlags x)) -> (SETG x)
    596 (SETG (InvertFlags x)) -> (SETL x)
    597 (SETB (InvertFlags x)) -> (SETA x)
    598 (SETA (InvertFlags x)) -> (SETB x)
    599 (SETLE (InvertFlags x)) -> (SETGE x)
    600 (SETGE (InvertFlags x)) -> (SETLE x)
    601 (SETBE (InvertFlags x)) -> (SETAE x)
    602 (SETAE (InvertFlags x)) -> (SETBE x)
    603 (SETEQ (InvertFlags x)) -> (SETEQ x)
    604 (SETNE (InvertFlags x)) -> (SETNE x)
    605 
    606 // sign extended loads
    607 // Note: The combined instruction must end up in the same block
    608 // as the original load. If not, we end up making a value with
    609 // memory type live in two different blocks, which can lead to
    610 // multiple memory values alive simultaneously.
    611 // Make sure we don't combine these ops if the load has another use.
    612 // This prevents a single load from being split into multiple loads
    613 // which then might return different values.  See test/atomicload.go.
    614 (MOVBLSX x:(MOVBload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVBLSXload <v.Type> [off] {sym} ptr mem)
    615 (MOVBLZX x:(MOVBload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVBload <v.Type> [off] {sym} ptr mem)
    616 (MOVWLSX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWLSXload <v.Type> [off] {sym} ptr mem)
    617 (MOVWLZX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWload <v.Type> [off] {sym} ptr mem)
    618 
    619 (MOVBLZX x:(MOVBloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVBloadidx1 <v.Type> [off] {sym} ptr idx mem)
    620 (MOVWLZX x:(MOVWloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWloadidx1 <v.Type> [off] {sym} ptr idx mem)
    621 (MOVWLZX x:(MOVWloadidx2 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWloadidx2 <v.Type> [off] {sym} ptr idx mem)
    622 
    623 // replace load from same location as preceding store with copy
    624 (MOVBload [off] {sym} ptr (MOVBstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
    625 (MOVWload [off] {sym} ptr (MOVWstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
    626 (MOVLload [off] {sym} ptr (MOVLstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
    627 
    628 // Fold extensions and ANDs together.
    629 (MOVBLZX (ANDLconst [c] x)) -> (ANDLconst [c & 0xff] x)
    630 (MOVWLZX (ANDLconst [c] x)) -> (ANDLconst [c & 0xffff] x)
    631 (MOVBLSX (ANDLconst [c] x)) && c & 0x80 == 0 -> (ANDLconst [c & 0x7f] x)
    632 (MOVWLSX (ANDLconst [c] x)) && c & 0x8000 == 0 -> (ANDLconst [c & 0x7fff] x)
    633 
    634 // Don't extend before storing
    635 (MOVWstore [off] {sym} ptr (MOVWLSX x) mem) -> (MOVWstore [off] {sym} ptr x mem)
    636 (MOVBstore [off] {sym} ptr (MOVBLSX x) mem) -> (MOVBstore [off] {sym} ptr x mem)
    637 (MOVWstore [off] {sym} ptr (MOVWLZX x) mem) -> (MOVWstore [off] {sym} ptr x mem)
    638 (MOVBstore [off] {sym} ptr (MOVBLZX x) mem) -> (MOVBstore [off] {sym} ptr x mem)
    639 
    640 // fold constants into memory operations
    641 // Note that this is not always a good idea because if not all the uses of
    642 // the ADDQconst get eliminated, we still have to compute the ADDQconst and we now
    643 // have potentially two live values (ptr and (ADDQconst [off] ptr)) instead of one.
    644 // Nevertheless, let's do it!
    645 (MOVLload  [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVLload  [off1+off2] {sym} ptr mem)
    646 (MOVWload  [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVWload  [off1+off2] {sym} ptr mem)
    647 (MOVBload  [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVBload  [off1+off2] {sym} ptr mem)
    648 (MOVSSload [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVSSload [off1+off2] {sym} ptr mem)
    649 (MOVSDload [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVSDload [off1+off2] {sym} ptr mem)
    650 
    651 (MOVLstore  [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVLstore  [off1+off2] {sym} ptr val mem)
    652 (MOVWstore  [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVWstore  [off1+off2] {sym} ptr val mem)
    653 (MOVBstore  [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVBstore  [off1+off2] {sym} ptr val mem)
    654 (MOVSSstore [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVSSstore [off1+off2] {sym} ptr val mem)
    655 (MOVSDstore [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVSDstore [off1+off2] {sym} ptr val mem)
    656 
    657 // Fold constants into stores.
    658 (MOVLstore [off] {sym} ptr (MOVLconst [c]) mem) && validOff(off) ->
    659 	(MOVLstoreconst [makeValAndOff(int64(int32(c)),off)] {sym} ptr mem)
    660 (MOVWstore [off] {sym} ptr (MOVLconst [c]) mem) && validOff(off) ->
    661 	(MOVWstoreconst [makeValAndOff(int64(int16(c)),off)] {sym} ptr mem)
    662 (MOVBstore [off] {sym} ptr (MOVLconst [c]) mem) && validOff(off) ->
    663 	(MOVBstoreconst [makeValAndOff(int64(int8(c)),off)] {sym} ptr mem)
    664 
    665 // Fold address offsets into constant stores.
    666 (MOVLstoreconst [sc] {s} (ADDLconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
    667 	(MOVLstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
    668 (MOVWstoreconst [sc] {s} (ADDLconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
    669 	(MOVWstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
    670 (MOVBstoreconst [sc] {s} (ADDLconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
    671 	(MOVBstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
    672 
    673 // We need to fold LEAQ into the MOVx ops so that the live variable analysis knows
    674 // what variables are being read/written by the ops.
    675 // Note: we turn off this merging for operations on globals when building
    676 // position-independent code (when Flag_shared is set).
    677 // PIC needs a spare register to load the PC into.  Having the LEAL be
    678 // a separate instruction gives us that register.  Having the LEAL be
    679 // a separate instruction also allows it to be CSEd (which is good because
    680 // it compiles to a thunk call).
    681 (MOVLload  [off1] {sym1} (LEAL [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    682   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    683 	(MOVLload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
    684 (MOVWload  [off1] {sym1} (LEAL [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    685   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    686 	(MOVWload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
    687 (MOVBload  [off1] {sym1} (LEAL [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    688   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    689 	(MOVBload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
    690 (MOVSSload [off1] {sym1} (LEAL [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    691   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    692 	(MOVSSload [off1+off2] {mergeSym(sym1,sym2)} base mem)
    693 (MOVSDload [off1] {sym1} (LEAL [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    694   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    695 	(MOVSDload [off1+off2] {mergeSym(sym1,sym2)} base mem)
    696 
    697 (MOVBLSXload [off1] {sym1} (LEAL [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    698   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    699 	(MOVBLSXload [off1+off2] {mergeSym(sym1,sym2)} base mem)
    700 (MOVWLSXload [off1] {sym1} (LEAL [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    701   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    702 	(MOVWLSXload [off1+off2] {mergeSym(sym1,sym2)} base mem)
    703 
    704 (MOVLstore  [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    705   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    706 	(MOVLstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
    707 (MOVWstore  [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    708   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    709 	(MOVWstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
    710 (MOVBstore  [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    711   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    712 	(MOVBstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
    713 (MOVSSstore [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    714   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    715 	(MOVSSstore [off1+off2] {mergeSym(sym1,sym2)} base val mem)
    716 (MOVSDstore [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2)
    717   && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
    718 	(MOVSDstore [off1+off2] {mergeSym(sym1,sym2)} base val mem)
    719 
    720 (MOVLstoreconst [sc] {sym1} (LEAL [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off)
    721   && (ptr.Op != OpSB || !config.ctxt.Flag_shared) ->
    722 	(MOVLstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
    723 (MOVWstoreconst [sc] {sym1} (LEAL [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off)
    724   && (ptr.Op != OpSB || !config.ctxt.Flag_shared) ->
    725 	(MOVWstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
    726 (MOVBstoreconst [sc] {sym1} (LEAL [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off)
    727   && (ptr.Op != OpSB || !config.ctxt.Flag_shared) ->
    728 	(MOVBstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
    729 
    730 // generating indexed loads and stores
    731 (MOVBload [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    732 	(MOVBloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    733 (MOVWload [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    734 	(MOVWloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    735 (MOVWload [off1] {sym1} (LEAL2 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    736 	(MOVWloadidx2 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    737 (MOVLload [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    738 	(MOVLloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    739 (MOVLload [off1] {sym1} (LEAL4 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    740 	(MOVLloadidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    741 (MOVSSload [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    742 	(MOVSSloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    743 (MOVSSload [off1] {sym1} (LEAL4 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    744 	(MOVSSloadidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    745 (MOVSDload [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    746 	(MOVSDloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    747 (MOVSDload [off1] {sym1} (LEAL8 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    748 	(MOVSDloadidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
    749 
    750 (MOVBstore [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    751 	(MOVBstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    752 (MOVWstore [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    753 	(MOVWstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    754 (MOVWstore [off1] {sym1} (LEAL2 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    755 	(MOVWstoreidx2 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    756 (MOVLstore [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    757 	(MOVLstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    758 (MOVLstore [off1] {sym1} (LEAL4 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    759 	(MOVLstoreidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    760 (MOVSSstore [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    761 	(MOVSSstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    762 (MOVSSstore [off1] {sym1} (LEAL4 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    763 	(MOVSSstoreidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    764 (MOVSDstore [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    765 	(MOVSDstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    766 (MOVSDstore [off1] {sym1} (LEAL8 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    767 	(MOVSDstoreidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
    768 
    769 (MOVBload [off] {sym} (ADDL ptr idx) mem) && ptr.Op != OpSB -> (MOVBloadidx1 [off] {sym} ptr idx mem)
    770 (MOVWload [off] {sym} (ADDL ptr idx) mem) && ptr.Op != OpSB -> (MOVWloadidx1 [off] {sym} ptr idx mem)
    771 (MOVLload [off] {sym} (ADDL ptr idx) mem) && ptr.Op != OpSB -> (MOVLloadidx1 [off] {sym} ptr idx mem)
    772 (MOVSSload [off] {sym} (ADDL ptr idx) mem) && ptr.Op != OpSB -> (MOVSSloadidx1 [off] {sym} ptr idx mem)
    773 (MOVSDload [off] {sym} (ADDL ptr idx) mem) && ptr.Op != OpSB -> (MOVSDloadidx1 [off] {sym} ptr idx mem)
    774 (MOVBstore [off] {sym} (ADDL ptr idx) val mem) && ptr.Op != OpSB -> (MOVBstoreidx1 [off] {sym} ptr idx val mem)
    775 (MOVWstore [off] {sym} (ADDL ptr idx) val mem) && ptr.Op != OpSB -> (MOVWstoreidx1 [off] {sym} ptr idx val mem)
    776 (MOVLstore [off] {sym} (ADDL ptr idx) val mem) && ptr.Op != OpSB -> (MOVLstoreidx1 [off] {sym} ptr idx val mem)
    777 (MOVSSstore [off] {sym} (ADDL ptr idx) val mem) && ptr.Op != OpSB -> (MOVSSstoreidx1 [off] {sym} ptr idx val mem)
    778 (MOVSDstore [off] {sym} (ADDL ptr idx) val mem) && ptr.Op != OpSB -> (MOVSDstoreidx1 [off] {sym} ptr idx val mem)
    779 
    780 (MOVBstoreconst [x] {sym1} (LEAL1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
    781 	(MOVBstoreconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
    782 (MOVWstoreconst [x] {sym1} (LEAL1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
    783 	(MOVWstoreconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
    784 (MOVWstoreconst [x] {sym1} (LEAL2 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
    785 	(MOVWstoreconstidx2 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
    786 (MOVLstoreconst [x] {sym1} (LEAL1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
    787 	(MOVLstoreconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
    788 (MOVLstoreconst [x] {sym1} (LEAL4 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
    789 	(MOVLstoreconstidx4 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
    790 
    791 (MOVBstoreconst [x] {sym} (ADDL ptr idx) mem) -> (MOVBstoreconstidx1 [x] {sym} ptr idx mem)
    792 (MOVWstoreconst [x] {sym} (ADDL ptr idx) mem) -> (MOVWstoreconstidx1 [x] {sym} ptr idx mem)
    793 (MOVLstoreconst [x] {sym} (ADDL ptr idx) mem) -> (MOVLstoreconstidx1 [x] {sym} ptr idx mem)
    794 
    795 // combine SHLL into indexed loads and stores
    796 (MOVWloadidx1 [c] {sym} ptr (SHLLconst [1] idx) mem) -> (MOVWloadidx2 [c] {sym} ptr idx mem)
    797 (MOVLloadidx1 [c] {sym} ptr (SHLLconst [2] idx) mem) -> (MOVLloadidx4 [c] {sym} ptr idx mem)
    798 (MOVWstoreidx1 [c] {sym} ptr (SHLLconst [1] idx) val mem) -> (MOVWstoreidx2 [c] {sym} ptr idx val mem)
    799 (MOVLstoreidx1 [c] {sym} ptr (SHLLconst [2] idx) val mem) -> (MOVLstoreidx4 [c] {sym} ptr idx val mem)
    800 (MOVWstoreconstidx1 [c] {sym} ptr (SHLLconst [1] idx) mem) -> (MOVWstoreconstidx2 [c] {sym} ptr idx mem)
    801 (MOVLstoreconstidx1 [c] {sym} ptr (SHLLconst [2] idx) mem) -> (MOVLstoreconstidx4 [c] {sym} ptr idx mem)
    802 
    803 // combine ADDL into indexed loads and stores
    804 (MOVBloadidx1 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVBloadidx1 [c+d] {sym} ptr idx mem)
    805 (MOVWloadidx1 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVWloadidx1 [c+d] {sym} ptr idx mem)
    806 (MOVWloadidx2 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVWloadidx2 [c+d] {sym} ptr idx mem)
    807 (MOVLloadidx1 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVLloadidx1 [c+d] {sym} ptr idx mem)
    808 (MOVLloadidx4 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVLloadidx4 [c+d] {sym} ptr idx mem)
    809 (MOVSSloadidx1 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVSSloadidx1 [c+d] {sym} ptr idx mem)
    810 (MOVSSloadidx4 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVSSloadidx4 [c+d] {sym} ptr idx mem)
    811 (MOVSDloadidx1 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVSDloadidx1 [c+d] {sym} ptr idx mem)
    812 (MOVSDloadidx8 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVSDloadidx8 [c+d] {sym} ptr idx mem)
    813 
    814 (MOVBstoreidx1 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVBstoreidx1 [c+d] {sym} ptr idx val mem)
    815 (MOVWstoreidx1 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVWstoreidx1 [c+d] {sym} ptr idx val mem)
    816 (MOVWstoreidx2 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVWstoreidx2 [c+d] {sym} ptr idx val mem)
    817 (MOVLstoreidx1 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVLstoreidx1 [c+d] {sym} ptr idx val mem)
    818 (MOVLstoreidx4 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVLstoreidx4 [c+d] {sym} ptr idx val mem)
    819 (MOVSSstoreidx1 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVSSstoreidx1 [c+d] {sym} ptr idx val mem)
    820 (MOVSSstoreidx4 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVSSstoreidx4 [c+d] {sym} ptr idx val mem)
    821 (MOVSDstoreidx1 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVSDstoreidx1 [c+d] {sym} ptr idx val mem)
    822 (MOVSDstoreidx8 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVSDstoreidx8 [c+d] {sym} ptr idx val mem)
    823 
    824 (MOVBloadidx1 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVBloadidx1 [c+d] {sym} ptr idx mem)
    825 (MOVWloadidx1 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVWloadidx1 [c+d] {sym} ptr idx mem)
    826 (MOVWloadidx2 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVWloadidx2 [c+2*d] {sym} ptr idx mem)
    827 (MOVLloadidx1 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVLloadidx1 [c+d] {sym} ptr idx mem)
    828 (MOVLloadidx4 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVLloadidx4 [c+4*d] {sym} ptr idx mem)
    829 (MOVSSloadidx1 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVSSloadidx1 [c+d] {sym} ptr idx mem)
    830 (MOVSSloadidx4 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVSSloadidx4 [c+4*d] {sym} ptr idx mem)
    831 (MOVSDloadidx1 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVSDloadidx1 [c+d] {sym} ptr idx mem)
    832 (MOVSDloadidx8 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVSDloadidx8 [c+8*d] {sym} ptr idx mem)
    833 
    834 (MOVBstoreidx1 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVBstoreidx1 [c+d] {sym} ptr idx val mem)
    835 (MOVWstoreidx1 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVWstoreidx1 [c+d] {sym} ptr idx val mem)
    836 (MOVWstoreidx2 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVWstoreidx2 [c+2*d] {sym} ptr idx val mem)
    837 (MOVLstoreidx1 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVLstoreidx1 [c+d] {sym} ptr idx val mem)
    838 (MOVLstoreidx4 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVLstoreidx4 [c+4*d] {sym} ptr idx val mem)
    839 (MOVSSstoreidx1 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVSSstoreidx1 [c+d] {sym} ptr idx val mem)
    840 (MOVSSstoreidx4 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVSSstoreidx4 [c+4*d] {sym} ptr idx val mem)
    841 (MOVSDstoreidx1 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVSDstoreidx1 [c+d] {sym} ptr idx val mem)
    842 (MOVSDstoreidx8 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVSDstoreidx8 [c+8*d] {sym} ptr idx val mem)
    843 
    844 (MOVBstoreconstidx1 [x] {sym} (ADDLconst [c] ptr) idx mem) ->
    845 	(MOVBstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
    846 (MOVWstoreconstidx1 [x] {sym} (ADDLconst [c] ptr) idx mem) ->
    847 	(MOVWstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
    848 (MOVWstoreconstidx2 [x] {sym} (ADDLconst [c] ptr) idx mem) ->
    849 	(MOVWstoreconstidx2 [ValAndOff(x).add(c)] {sym} ptr idx mem)
    850 (MOVLstoreconstidx1 [x] {sym} (ADDLconst [c] ptr) idx mem) ->
    851 	(MOVLstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
    852 (MOVLstoreconstidx4 [x] {sym} (ADDLconst [c] ptr) idx mem) ->
    853 	(MOVLstoreconstidx4 [ValAndOff(x).add(c)] {sym} ptr idx mem)
    854 
    855 (MOVBstoreconstidx1 [x] {sym} ptr (ADDLconst [c] idx) mem) ->
    856 	(MOVBstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
    857 (MOVWstoreconstidx1 [x] {sym} ptr (ADDLconst [c] idx) mem) ->
    858 	(MOVWstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
    859 (MOVWstoreconstidx2 [x] {sym} ptr (ADDLconst [c] idx) mem) ->
    860 	(MOVWstoreconstidx2 [ValAndOff(x).add(2*c)] {sym} ptr idx mem)
    861 (MOVLstoreconstidx1 [x] {sym} ptr (ADDLconst [c] idx) mem) ->
    862 	(MOVLstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
    863 (MOVLstoreconstidx4 [x] {sym} ptr (ADDLconst [c] idx) mem) ->
    864 	(MOVLstoreconstidx4 [ValAndOff(x).add(4*c)] {sym} ptr idx mem)
    865 
    866 // fold LEALs together
    867 (LEAL [off1] {sym1} (LEAL [off2] {sym2} x)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    868       (LEAL [off1+off2] {mergeSym(sym1,sym2)} x)
    869 
    870 // LEAL into LEAL1
    871 (LEAL1 [off1] {sym1} (LEAL [off2] {sym2} x) y) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && x.Op != OpSB ->
    872        (LEAL1 [off1+off2] {mergeSym(sym1,sym2)} x y)
    873 (LEAL1 [off1] {sym1} x (LEAL [off2] {sym2} y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && y.Op != OpSB ->
    874        (LEAL1 [off1+off2] {mergeSym(sym1,sym2)} x y)
    875 
    876 // LEAL1 into LEAL
    877 (LEAL [off1] {sym1} (LEAL1 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    878        (LEAL1 [off1+off2] {mergeSym(sym1,sym2)} x y)
    879 
    880 // LEAL into LEAL[248]
    881 (LEAL2 [off1] {sym1} (LEAL [off2] {sym2} x) y) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && x.Op != OpSB ->
    882        (LEAL2 [off1+off2] {mergeSym(sym1,sym2)} x y)
    883 (LEAL4 [off1] {sym1} (LEAL [off2] {sym2} x) y) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && x.Op != OpSB ->
    884        (LEAL4 [off1+off2] {mergeSym(sym1,sym2)} x y)
    885 (LEAL8 [off1] {sym1} (LEAL [off2] {sym2} x) y) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && x.Op != OpSB ->
    886        (LEAL8 [off1+off2] {mergeSym(sym1,sym2)} x y)
    887 
    888 // LEAL[248] into LEAL
    889 (LEAL [off1] {sym1} (LEAL2 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    890       (LEAL2 [off1+off2] {mergeSym(sym1,sym2)} x y)
    891 (LEAL [off1] {sym1} (LEAL4 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    892       (LEAL4 [off1+off2] {mergeSym(sym1,sym2)} x y)
    893 (LEAL [off1] {sym1} (LEAL8 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
    894       (LEAL8 [off1+off2] {mergeSym(sym1,sym2)} x y)
    895 
    896 // Absorb InvertFlags into branches.
    897 (LT (InvertFlags cmp) yes no) -> (GT cmp yes no)
    898 (GT (InvertFlags cmp) yes no) -> (LT cmp yes no)
    899 (LE (InvertFlags cmp) yes no) -> (GE cmp yes no)
    900 (GE (InvertFlags cmp) yes no) -> (LE cmp yes no)
    901 (ULT (InvertFlags cmp) yes no) -> (UGT cmp yes no)
    902 (UGT (InvertFlags cmp) yes no) -> (ULT cmp yes no)
    903 (ULE (InvertFlags cmp) yes no) -> (UGE cmp yes no)
    904 (UGE (InvertFlags cmp) yes no) -> (ULE cmp yes no)
    905 (EQ (InvertFlags cmp) yes no) -> (EQ cmp yes no)
    906 (NE (InvertFlags cmp) yes no) -> (NE cmp yes no)
    907 
    908 // Constant comparisons.
    909 (CMPLconst (MOVLconst [x]) [y]) && int32(x)==int32(y) -> (FlagEQ)
    910 (CMPLconst (MOVLconst [x]) [y]) && int32(x)<int32(y) && uint32(x)<uint32(y) -> (FlagLT_ULT)
    911 (CMPLconst (MOVLconst [x]) [y]) && int32(x)<int32(y) && uint32(x)>uint32(y) -> (FlagLT_UGT)
    912 (CMPLconst (MOVLconst [x]) [y]) && int32(x)>int32(y) && uint32(x)<uint32(y) -> (FlagGT_ULT)
    913 (CMPLconst (MOVLconst [x]) [y]) && int32(x)>int32(y) && uint32(x)>uint32(y) -> (FlagGT_UGT)
    914 (CMPWconst (MOVLconst [x]) [y]) && int16(x)==int16(y) -> (FlagEQ)
    915 (CMPWconst (MOVLconst [x]) [y]) && int16(x)<int16(y) && uint16(x)<uint16(y) -> (FlagLT_ULT)
    916 (CMPWconst (MOVLconst [x]) [y]) && int16(x)<int16(y) && uint16(x)>uint16(y) -> (FlagLT_UGT)
    917 (CMPWconst (MOVLconst [x]) [y]) && int16(x)>int16(y) && uint16(x)<uint16(y) -> (FlagGT_ULT)
    918 (CMPWconst (MOVLconst [x]) [y]) && int16(x)>int16(y) && uint16(x)>uint16(y) -> (FlagGT_UGT)
    919 (CMPBconst (MOVLconst [x]) [y]) && int8(x)==int8(y) -> (FlagEQ)
    920 (CMPBconst (MOVLconst [x]) [y]) && int8(x)<int8(y) && uint8(x)<uint8(y) -> (FlagLT_ULT)
    921 (CMPBconst (MOVLconst [x]) [y]) && int8(x)<int8(y) && uint8(x)>uint8(y) -> (FlagLT_UGT)
    922 (CMPBconst (MOVLconst [x]) [y]) && int8(x)>int8(y) && uint8(x)<uint8(y) -> (FlagGT_ULT)
    923 (CMPBconst (MOVLconst [x]) [y]) && int8(x)>int8(y) && uint8(x)>uint8(y) -> (FlagGT_UGT)
    924 
    925 // Other known comparisons.
    926 (CMPLconst (SHRLconst _ [c]) [n]) && 0 <= n && 0 < c && c <= 32 && (1<<uint64(32-c)) <= uint64(n) -> (FlagLT_ULT)
    927 (CMPLconst (ANDLconst _ [m]) [n]) && 0 <= int32(m) && int32(m) < int32(n) -> (FlagLT_ULT)
    928 (CMPWconst (ANDLconst _ [m]) [n]) && 0 <= int16(m) && int16(m) < int16(n) -> (FlagLT_ULT)
    929 (CMPBconst (ANDLconst _ [m]) [n]) && 0 <= int8(m) && int8(m) < int8(n) -> (FlagLT_ULT)
    930 // TODO: DIVxU also.
    931 
    932 // Absorb flag constants into SBB ops.
    933 (SBBLcarrymask (FlagEQ)) -> (MOVLconst [0])
    934 (SBBLcarrymask (FlagLT_ULT)) -> (MOVLconst [-1])
    935 (SBBLcarrymask (FlagLT_UGT)) -> (MOVLconst [0])
    936 (SBBLcarrymask (FlagGT_ULT)) -> (MOVLconst [-1])
    937 (SBBLcarrymask (FlagGT_UGT)) -> (MOVLconst [0])
    938 
    939 // Absorb flag constants into branches.
    940 (EQ (FlagEQ) yes no) -> (First nil yes no)
    941 (EQ (FlagLT_ULT) yes no) -> (First nil no yes)
    942 (EQ (FlagLT_UGT) yes no) -> (First nil no yes)
    943 (EQ (FlagGT_ULT) yes no) -> (First nil no yes)
    944 (EQ (FlagGT_UGT) yes no) -> (First nil no yes)
    945 
    946 (NE (FlagEQ) yes no) -> (First nil no yes)
    947 (NE (FlagLT_ULT) yes no) -> (First nil yes no)
    948 (NE (FlagLT_UGT) yes no) -> (First nil yes no)
    949 (NE (FlagGT_ULT) yes no) -> (First nil yes no)
    950 (NE (FlagGT_UGT) yes no) -> (First nil yes no)
    951 
    952 (LT (FlagEQ) yes no) -> (First nil no yes)
    953 (LT (FlagLT_ULT) yes no) -> (First nil yes no)
    954 (LT (FlagLT_UGT) yes no) -> (First nil yes no)
    955 (LT (FlagGT_ULT) yes no) -> (First nil no yes)
    956 (LT (FlagGT_UGT) yes no) -> (First nil no yes)
    957 
    958 (LE (FlagEQ) yes no) -> (First nil yes no)
    959 (LE (FlagLT_ULT) yes no) -> (First nil yes no)
    960 (LE (FlagLT_UGT) yes no) -> (First nil yes no)
    961 (LE (FlagGT_ULT) yes no) -> (First nil no yes)
    962 (LE (FlagGT_UGT) yes no) -> (First nil no yes)
    963 
    964 (GT (FlagEQ) yes no) -> (First nil no yes)
    965 (GT (FlagLT_ULT) yes no) -> (First nil no yes)
    966 (GT (FlagLT_UGT) yes no) -> (First nil no yes)
    967 (GT (FlagGT_ULT) yes no) -> (First nil yes no)
    968 (GT (FlagGT_UGT) yes no) -> (First nil yes no)
    969 
    970 (GE (FlagEQ) yes no) -> (First nil yes no)
    971 (GE (FlagLT_ULT) yes no) -> (First nil no yes)
    972 (GE (FlagLT_UGT) yes no) -> (First nil no yes)
    973 (GE (FlagGT_ULT) yes no) -> (First nil yes no)
    974 (GE (FlagGT_UGT) yes no) -> (First nil yes no)
    975 
    976 (ULT (FlagEQ) yes no) -> (First nil no yes)
    977 (ULT (FlagLT_ULT) yes no) -> (First nil yes no)
    978 (ULT (FlagLT_UGT) yes no) -> (First nil no yes)
    979 (ULT (FlagGT_ULT) yes no) -> (First nil yes no)
    980 (ULT (FlagGT_UGT) yes no) -> (First nil no yes)
    981 
    982 (ULE (FlagEQ) yes no) -> (First nil yes no)
    983 (ULE (FlagLT_ULT) yes no) -> (First nil yes no)
    984 (ULE (FlagLT_UGT) yes no) -> (First nil no yes)
    985 (ULE (FlagGT_ULT) yes no) -> (First nil yes no)
    986 (ULE (FlagGT_UGT) yes no) -> (First nil no yes)
    987 
    988 (UGT (FlagEQ) yes no) -> (First nil no yes)
    989 (UGT (FlagLT_ULT) yes no) -> (First nil no yes)
    990 (UGT (FlagLT_UGT) yes no) -> (First nil yes no)
    991 (UGT (FlagGT_ULT) yes no) -> (First nil no yes)
    992 (UGT (FlagGT_UGT) yes no) -> (First nil yes no)
    993 
    994 (UGE (FlagEQ) yes no) -> (First nil yes no)
    995 (UGE (FlagLT_ULT) yes no) -> (First nil no yes)
    996 (UGE (FlagLT_UGT) yes no) -> (First nil yes no)
    997 (UGE (FlagGT_ULT) yes no) -> (First nil no yes)
    998 (UGE (FlagGT_UGT) yes no) -> (First nil yes no)
    999 
   1000 // Absorb flag constants into SETxx ops.
   1001 (SETEQ (FlagEQ)) -> (MOVLconst [1])
   1002 (SETEQ (FlagLT_ULT)) -> (MOVLconst [0])
   1003 (SETEQ (FlagLT_UGT)) -> (MOVLconst [0])
   1004 (SETEQ (FlagGT_ULT)) -> (MOVLconst [0])
   1005 (SETEQ (FlagGT_UGT)) -> (MOVLconst [0])
   1006 
   1007 (SETNE (FlagEQ)) -> (MOVLconst [0])
   1008 (SETNE (FlagLT_ULT)) -> (MOVLconst [1])
   1009 (SETNE (FlagLT_UGT)) -> (MOVLconst [1])
   1010 (SETNE (FlagGT_ULT)) -> (MOVLconst [1])
   1011 (SETNE (FlagGT_UGT)) -> (MOVLconst [1])
   1012 
   1013 (SETL (FlagEQ)) -> (MOVLconst [0])
   1014 (SETL (FlagLT_ULT)) -> (MOVLconst [1])
   1015 (SETL (FlagLT_UGT)) -> (MOVLconst [1])
   1016 (SETL (FlagGT_ULT)) -> (MOVLconst [0])
   1017 (SETL (FlagGT_UGT)) -> (MOVLconst [0])
   1018 
   1019 (SETLE (FlagEQ)) -> (MOVLconst [1])
   1020 (SETLE (FlagLT_ULT)) -> (MOVLconst [1])
   1021 (SETLE (FlagLT_UGT)) -> (MOVLconst [1])
   1022 (SETLE (FlagGT_ULT)) -> (MOVLconst [0])
   1023 (SETLE (FlagGT_UGT)) -> (MOVLconst [0])
   1024 
   1025 (SETG (FlagEQ)) -> (MOVLconst [0])
   1026 (SETG (FlagLT_ULT)) -> (MOVLconst [0])
   1027 (SETG (FlagLT_UGT)) -> (MOVLconst [0])
   1028 (SETG (FlagGT_ULT)) -> (MOVLconst [1])
   1029 (SETG (FlagGT_UGT)) -> (MOVLconst [1])
   1030 
   1031 (SETGE (FlagEQ)) -> (MOVLconst [1])
   1032 (SETGE (FlagLT_ULT)) -> (MOVLconst [0])
   1033 (SETGE (FlagLT_UGT)) -> (MOVLconst [0])
   1034 (SETGE (FlagGT_ULT)) -> (MOVLconst [1])
   1035 (SETGE (FlagGT_UGT)) -> (MOVLconst [1])
   1036 
   1037 (SETB (FlagEQ)) -> (MOVLconst [0])
   1038 (SETB (FlagLT_ULT)) -> (MOVLconst [1])
   1039 (SETB (FlagLT_UGT)) -> (MOVLconst [0])
   1040 (SETB (FlagGT_ULT)) -> (MOVLconst [1])
   1041 (SETB (FlagGT_UGT)) -> (MOVLconst [0])
   1042 
   1043 (SETBE (FlagEQ)) -> (MOVLconst [1])
   1044 (SETBE (FlagLT_ULT)) -> (MOVLconst [1])
   1045 (SETBE (FlagLT_UGT)) -> (MOVLconst [0])
   1046 (SETBE (FlagGT_ULT)) -> (MOVLconst [1])
   1047 (SETBE (FlagGT_UGT)) -> (MOVLconst [0])
   1048 
   1049 (SETA (FlagEQ)) -> (MOVLconst [0])
   1050 (SETA (FlagLT_ULT)) -> (MOVLconst [0])
   1051 (SETA (FlagLT_UGT)) -> (MOVLconst [1])
   1052 (SETA (FlagGT_ULT)) -> (MOVLconst [0])
   1053 (SETA (FlagGT_UGT)) -> (MOVLconst [1])
   1054 
   1055 (SETAE (FlagEQ)) -> (MOVLconst [1])
   1056 (SETAE (FlagLT_ULT)) -> (MOVLconst [0])
   1057 (SETAE (FlagLT_UGT)) -> (MOVLconst [1])
   1058 (SETAE (FlagGT_ULT)) -> (MOVLconst [0])
   1059 (SETAE (FlagGT_UGT)) -> (MOVLconst [1])
   1060 
   1061 // Remove redundant *const ops
   1062 (ADDLconst [c] x) && int32(c)==0 -> x
   1063 (SUBLconst [c] x) && int32(c) == 0 -> x
   1064 (ANDLconst [c] _) && int32(c)==0  -> (MOVLconst [0])
   1065 (ANDLconst [c] x) && int32(c)==-1 -> x
   1066 (ORLconst [c] x) && int32(c)==0   -> x
   1067 (ORLconst [c] _) && int32(c)==-1  -> (MOVLconst [-1])
   1068 (XORLconst [c] x) && int32(c)==0   -> x
   1069 // TODO: since we got rid of the W/B versions, we might miss
   1070 // things like (ANDLconst [0x100] x) which were formerly
   1071 // (ANDBconst [0] x).  Probably doesn't happen very often.
   1072 // If we cared, we might do:
   1073 //  (ANDLconst <t> [c] x) && t.Size()==1 && int8(x)==0 -> (MOVLconst [0])
   1074 
   1075 // Convert constant subtracts to constant adds
   1076 (SUBLconst [c] x) -> (ADDLconst [int64(int32(-c))] x)
   1077 
   1078 // generic constant folding
   1079 // TODO: more of this
   1080 (ADDLconst [c] (MOVLconst [d])) -> (MOVLconst [int64(int32(c+d))])
   1081 (ADDLconst [c] (ADDLconst [d] x)) -> (ADDLconst [int64(int32(c+d))] x)
   1082 (SARLconst [c] (MOVLconst [d])) -> (MOVLconst [d>>uint64(c)])
   1083 (SARWconst [c] (MOVLconst [d])) -> (MOVLconst [d>>uint64(c)])
   1084 (SARBconst [c] (MOVLconst [d])) -> (MOVLconst [d>>uint64(c)])
   1085 (NEGL (MOVLconst [c])) -> (MOVLconst [int64(int32(-c))])
   1086 (MULLconst [c] (MOVLconst [d])) -> (MOVLconst [int64(int32(c*d))])
   1087 (ANDLconst [c] (MOVLconst [d])) -> (MOVLconst [c&d])
   1088 (ORLconst [c] (MOVLconst [d])) -> (MOVLconst [c|d])
   1089 (XORLconst [c] (MOVLconst [d])) -> (MOVLconst [c^d])
   1090 (NOTL (MOVLconst [c])) -> (MOVLconst [^c])
   1091 
   1092 // generic simplifications
   1093 // TODO: more of this
   1094 (ADDL x (NEGL y)) -> (SUBL x y)
   1095 (SUBL x x) -> (MOVLconst [0])
   1096 (ANDL x x) -> x
   1097 (ORL x x) -> x
   1098 (XORL x x) -> (MOVLconst [0])
   1099 
   1100 // checking AND against 0.
   1101 (CMPLconst (ANDL x y) [0]) -> (TESTL x y)
   1102 (CMPWconst (ANDL x y) [0]) -> (TESTW x y)
   1103 (CMPBconst (ANDL x y) [0]) -> (TESTB x y)
   1104 (CMPLconst (ANDLconst [c] x) [0]) -> (TESTLconst [c] x)
   1105 (CMPWconst (ANDLconst [c] x) [0]) -> (TESTWconst [int64(int16(c))] x)
   1106 (CMPBconst (ANDLconst [c] x) [0]) -> (TESTBconst [int64(int8(c))] x)
   1107 
   1108 // TEST %reg,%reg is shorter than CMP
   1109 (CMPLconst x [0]) -> (TESTL x x)
   1110 (CMPWconst x [0]) -> (TESTW x x)
   1111 (CMPBconst x [0]) -> (TESTB x x)
   1112 
   1113 // Combining byte loads into larger (unaligned) loads.
   1114 // There are many ways these combinations could occur.  This is
   1115 // designed to match the way encoding/binary.LittleEndian does it.
   1116 (ORL                  x0:(MOVBload [i]   {s} p mem)
   1117     s0:(SHLLconst [8] x1:(MOVBload [i+1] {s} p mem)))
   1118   && x0.Uses == 1
   1119   && x1.Uses == 1
   1120   && s0.Uses == 1
   1121   && mergePoint(b,x0,x1) != nil
   1122   && clobber(x0)
   1123   && clobber(x1)
   1124   && clobber(s0)
   1125   -> @mergePoint(b,x0,x1) (MOVWload [i] {s} p mem)
   1126 
   1127 (ORL o0:(ORL
   1128                        x0:(MOVWload [i]   {s} p mem)
   1129     s0:(SHLLconst [16] x1:(MOVBload [i+2] {s} p mem)))
   1130     s1:(SHLLconst [24] x2:(MOVBload [i+3] {s} p mem)))
   1131   && x0.Uses == 1
   1132   && x1.Uses == 1
   1133   && x2.Uses == 1
   1134   && s0.Uses == 1
   1135   && s1.Uses == 1
   1136   && o0.Uses == 1
   1137   && mergePoint(b,x0,x1,x2) != nil
   1138   && clobber(x0)
   1139   && clobber(x1)
   1140   && clobber(x2)
   1141   && clobber(s0)
   1142   && clobber(s1)
   1143   && clobber(o0)
   1144   -> @mergePoint(b,x0,x1,x2) (MOVLload [i] {s} p mem)
   1145 
   1146 (ORL                  x0:(MOVBloadidx1 [i]   {s} p idx mem)
   1147     s0:(SHLLconst [8] x1:(MOVBloadidx1 [i+1] {s} p idx mem)))
   1148   && x0.Uses == 1
   1149   && x1.Uses == 1
   1150   && s0.Uses == 1
   1151   && mergePoint(b,x0,x1) != nil
   1152   && clobber(x0)
   1153   && clobber(x1)
   1154   && clobber(s0)
   1155   -> @mergePoint(b,x0,x1) (MOVWloadidx1 <v.Type> [i] {s} p idx mem)
   1156 
   1157 (ORL o0:(ORL
   1158                        x0:(MOVWloadidx1 [i]   {s} p idx mem)
   1159     s0:(SHLLconst [16] x1:(MOVBloadidx1 [i+2] {s} p idx mem)))
   1160     s1:(SHLLconst [24] x2:(MOVBloadidx1 [i+3] {s} p idx mem)))
   1161   && x0.Uses == 1
   1162   && x1.Uses == 1
   1163   && x2.Uses == 1
   1164   && s0.Uses == 1
   1165   && s1.Uses == 1
   1166   && o0.Uses == 1
   1167   && mergePoint(b,x0,x1,x2) != nil
   1168   && clobber(x0)
   1169   && clobber(x1)
   1170   && clobber(x2)
   1171   && clobber(s0)
   1172   && clobber(s1)
   1173   && clobber(o0)
   1174   -> @mergePoint(b,x0,x1,x2) (MOVLloadidx1 <v.Type> [i] {s} p idx mem)
   1175 
   1176 // Combine constant stores into larger (unaligned) stores.
   1177 (MOVBstoreconst [c] {s} p x:(MOVBstoreconst [a] {s} p mem))
   1178   && x.Uses == 1
   1179   && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
   1180   && clobber(x)
   1181   -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p mem)
   1182 (MOVWstoreconst [c] {s} p x:(MOVWstoreconst [a] {s} p mem))
   1183   && x.Uses == 1
   1184   && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
   1185   && clobber(x)
   1186   -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p mem)
   1187 
   1188 (MOVBstoreconstidx1 [c] {s} p i x:(MOVBstoreconstidx1 [a] {s} p i mem))
   1189   && x.Uses == 1
   1190   && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
   1191   && clobber(x)
   1192   -> (MOVWstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p i mem)
   1193 (MOVWstoreconstidx1 [c] {s} p i x:(MOVWstoreconstidx1 [a] {s} p i mem))
   1194   && x.Uses == 1
   1195   && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
   1196   && clobber(x)
   1197   -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p i mem)
   1198 
   1199 (MOVWstoreconstidx2 [c] {s} p i x:(MOVWstoreconstidx2 [a] {s} p i mem))
   1200   && x.Uses == 1
   1201   && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
   1202   && clobber(x)
   1203   -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p (SHLLconst <i.Type> [1] i) mem)
   1204 
   1205 // Combine stores into larger (unaligned) stores.
   1206 (MOVBstore [i] {s} p (SHRLconst [8] w) x:(MOVBstore [i-1] {s} p w mem))
   1207   && x.Uses == 1
   1208   && clobber(x)
   1209   -> (MOVWstore [i-1] {s} p w mem)
   1210 (MOVBstore [i] {s} p (SHRLconst [j] w) x:(MOVBstore [i-1] {s} p w0:(SHRLconst [j-8] w) mem))
   1211   && x.Uses == 1
   1212   && clobber(x)
   1213   -> (MOVWstore [i-1] {s} p w0 mem)
   1214 (MOVWstore [i] {s} p (SHRLconst [16] w) x:(MOVWstore [i-2] {s} p w mem))
   1215   && x.Uses == 1
   1216   && clobber(x)
   1217   -> (MOVLstore [i-2] {s} p w mem)
   1218 (MOVWstore [i] {s} p (SHRLconst [j] w) x:(MOVWstore [i-2] {s} p w0:(SHRLconst [j-16] w) mem))
   1219   && x.Uses == 1
   1220   && clobber(x)
   1221   -> (MOVLstore [i-2] {s} p w0 mem)
   1222 
   1223 (MOVBstoreidx1 [i] {s} p idx (SHRLconst [8] w) x:(MOVBstoreidx1 [i-1] {s} p idx w mem))
   1224   && x.Uses == 1
   1225   && clobber(x)
   1226   -> (MOVWstoreidx1 [i-1] {s} p idx w mem)
   1227 (MOVBstoreidx1 [i] {s} p idx (SHRLconst [j] w) x:(MOVBstoreidx1 [i-1] {s} p idx w0:(SHRLconst [j-8] w) mem))
   1228   && x.Uses == 1
   1229   && clobber(x)
   1230   -> (MOVWstoreidx1 [i-1] {s} p idx w0 mem)
   1231 (MOVWstoreidx1 [i] {s} p idx (SHRLconst [16] w) x:(MOVWstoreidx1 [i-2] {s} p idx w mem))
   1232   && x.Uses == 1
   1233   && clobber(x)
   1234   -> (MOVLstoreidx1 [i-2] {s} p idx w mem)
   1235 (MOVWstoreidx1 [i] {s} p idx (SHRLconst [j] w) x:(MOVWstoreidx1 [i-2] {s} p idx w0:(SHRLconst [j-16] w) mem))
   1236   && x.Uses == 1
   1237   && clobber(x)
   1238   -> (MOVLstoreidx1 [i-2] {s} p idx w0 mem)
   1239 
   1240 (MOVWstoreidx2 [i] {s} p idx (SHRLconst [16] w) x:(MOVWstoreidx2 [i-2] {s} p idx w mem))
   1241   && x.Uses == 1
   1242   && clobber(x)
   1243   -> (MOVLstoreidx1 [i-2] {s} p (SHLLconst <idx.Type> [1] idx) w mem)
   1244 (MOVWstoreidx2 [i] {s} p idx (SHRLconst [j] w) x:(MOVWstoreidx2 [i-2] {s} p idx w0:(SHRLconst [j-16] w) mem))
   1245   && x.Uses == 1
   1246   && clobber(x)
   1247   -> (MOVLstoreidx1 [i-2] {s} p (SHLLconst <idx.Type> [1] idx) w0 mem)
   1248 
   1249 // For PIC, break floating-point constant loading into two instructions so we have
   1250 // a register to use for holding the address of the constant pool entry.
   1251 (MOVSSconst [c]) && config.ctxt.Flag_shared -> (MOVSSconst2 (MOVSSconst1 [c]))
   1252 (MOVSDconst [c]) && config.ctxt.Flag_shared -> (MOVSDconst2 (MOVSDconst1 [c]))
   1253