github.com/euank/go@v0.0.0-20160829210321-495514729181/src/cmd/compile/internal/ssa/gen/AMD64.rules (about)

     1  // Copyright 2015 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  (Add64  x y) -> (ADDQ  x y)
     7  (AddPtr x y) && config.PtrSize == 8 -> (ADDQ x y)
     8  (AddPtr x y) && config.PtrSize == 4 -> (ADDL x y)
     9  (Add32  x y) -> (ADDL  x y)
    10  (Add16  x y) -> (ADDL  x y)
    11  (Add8   x y) -> (ADDL  x y)
    12  (Add32F x y) -> (ADDSS x y)
    13  (Add64F x y) -> (ADDSD x y)
    14  
    15  (Sub64  x y) -> (SUBQ  x y)
    16  (SubPtr x y) && config.PtrSize == 8 -> (SUBQ x y)
    17  (SubPtr x y) && config.PtrSize == 4 -> (SUBL x y)
    18  (Sub32  x y) -> (SUBL  x y)
    19  (Sub16  x y) -> (SUBL  x y)
    20  (Sub8   x y) -> (SUBL  x y)
    21  (Sub32F x y) -> (SUBSS x y)
    22  (Sub64F x y) -> (SUBSD x y)
    23  
    24  (Mul64  x y) -> (MULQ  x y)
    25  (Mul32  x y) -> (MULL  x y)
    26  (Mul16  x y) -> (MULL  x y)
    27  (Mul8   x y) -> (MULL  x y)
    28  (Mul32F x y) -> (MULSS x y)
    29  (Mul64F x y) -> (MULSD x y)
    30  
    31  (Div32F x y) -> (DIVSS x y)
    32  (Div64F x y) -> (DIVSD x y)
    33  
    34  (Div64  x y) -> (Select0 (DIVQ  x y))
    35  (Div64u x y) -> (Select0 (DIVQU x y))
    36  (Div32  x y) -> (Select0 (DIVL  x y))
    37  (Div32u x y) -> (Select0 (DIVLU x y))
    38  (Div16  x y) -> (Select0 (DIVW  x y))
    39  (Div16u x y) -> (Select0 (DIVWU x y))
    40  (Div8   x y) -> (Select0 (DIVW  (SignExt8to16 x) (SignExt8to16 y)))
    41  (Div8u  x y) -> (Select0 (DIVWU (ZeroExt8to16 x) (ZeroExt8to16 y)))
    42  
    43  (Hmul64  x y) -> (HMULQ  x y)
    44  (Hmul64u x y) -> (HMULQU x y)
    45  (Hmul32  x y) -> (HMULL  x y)
    46  (Hmul32u x y) -> (HMULLU x y)
    47  (Hmul16  x y) -> (HMULW  x y)
    48  (Hmul16u x y) -> (HMULWU x y)
    49  (Hmul8   x y) -> (HMULB  x y)
    50  (Hmul8u  x y) -> (HMULBU x y)
    51  
    52  (Avg64u x y) -> (AVGQU x y)
    53  
    54  (Mod64  x y) -> (Select1 (DIVQ  x y))
    55  (Mod64u x y) -> (Select1 (DIVQU x y))
    56  (Mod32  x y) -> (Select1 (DIVL  x y))
    57  (Mod32u x y) -> (Select1 (DIVLU x y))
    58  (Mod16  x y) -> (Select1 (DIVW  x y))
    59  (Mod16u x y) -> (Select1 (DIVWU x y))
    60  (Mod8   x y) -> (Select1 (DIVW  (SignExt8to16 x) (SignExt8to16 y)))
    61  (Mod8u  x y) -> (Select1 (DIVWU (ZeroExt8to16 x) (ZeroExt8to16 y)))
    62  
    63  (And64 x y) -> (ANDQ x y)
    64  (And32 x y) -> (ANDL x y)
    65  (And16 x y) -> (ANDL x y)
    66  (And8  x y) -> (ANDL x y)
    67  
    68  (Or64 x y) -> (ORQ x y)
    69  (Or32 x y) -> (ORL x y)
    70  (Or16 x y) -> (ORL x y)
    71  (Or8  x y) -> (ORL x y)
    72  
    73  (Xor64 x y) -> (XORQ x y)
    74  (Xor32 x y) -> (XORL x y)
    75  (Xor16 x y) -> (XORL x y)
    76  (Xor8  x y) -> (XORL x y)
    77  
    78  (Neg64  x) -> (NEGQ x)
    79  (Neg32  x) -> (NEGL x)
    80  (Neg16  x) -> (NEGL x)
    81  (Neg8   x) -> (NEGL x)
    82  (Neg32F x) -> (PXOR x (MOVSSconst <config.Frontend().TypeFloat32()> [f2i(math.Copysign(0, -1))]))
    83  (Neg64F x) -> (PXOR x (MOVSDconst <config.Frontend().TypeFloat64()> [f2i(math.Copysign(0, -1))]))
    84  
    85  (Com64 x) -> (NOTQ x)
    86  (Com32 x) -> (NOTL x)
    87  (Com16 x) -> (NOTL x)
    88  (Com8  x) -> (NOTL x)
    89  
    90  // Lowering boolean ops
    91  (AndB x y) -> (ANDL x y)
    92  (OrB x y) -> (ORL x y)
    93  (Not x) -> (XORLconst [1] x)
    94  
    95  // Lowering pointer arithmetic
    96  (OffPtr [off] ptr) && config.PtrSize == 8 && is32Bit(off) -> (ADDQconst [off] ptr)
    97  (OffPtr [off] ptr) && config.PtrSize == 8 -> (ADDQ (MOVQconst [off]) ptr)
    98  (OffPtr [off] ptr) && config.PtrSize == 4 -> (ADDLconst [off] ptr)
    99  
   100  // Lowering other arithmetic
   101  (Ctz64 <t> x) -> (CMOVQEQ (Select0 <t> (BSFQ x)) (MOVQconst <t> [64]) (Select1 <TypeFlags> (BSFQ x)))
   102  (Ctz32 <t> x) -> (CMOVLEQ (Select0 <t> (BSFL x)) (MOVLconst <t> [32]) (Select1 <TypeFlags> (BSFL x)))
   103  
   104  (Bswap64 x) -> (BSWAPQ x)
   105  (Bswap32 x) -> (BSWAPL x)
   106  
   107  (Sqrt x) -> (SQRTSD x)
   108  
   109  // Lowering extension
   110  // Note: we always extend to 64 bits even though some ops don't need that many result bits.
   111  (SignExt8to16  x) -> (MOVBQSX x)
   112  (SignExt8to32  x) -> (MOVBQSX x)
   113  (SignExt8to64  x) -> (MOVBQSX x)
   114  (SignExt16to32 x) -> (MOVWQSX x)
   115  (SignExt16to64 x) -> (MOVWQSX x)
   116  (SignExt32to64 x) -> (MOVLQSX x)
   117  
   118  (ZeroExt8to16  x) -> (MOVBQZX x)
   119  (ZeroExt8to32  x) -> (MOVBQZX x)
   120  (ZeroExt8to64  x) -> (MOVBQZX x)
   121  (ZeroExt16to32 x) -> (MOVWQZX x)
   122  (ZeroExt16to64 x) -> (MOVWQZX x)
   123  (ZeroExt32to64 x) -> (MOVLQZX x)
   124  
   125  // Lowering truncation
   126  // Because we ignore high parts of registers, truncates are just copies.
   127  (Trunc16to8  x) -> x
   128  (Trunc32to8  x) -> x
   129  (Trunc32to16 x) -> x
   130  (Trunc64to8  x) -> x
   131  (Trunc64to16 x) -> x
   132  (Trunc64to32 x) -> x
   133  
   134  // Lowering float <-> int
   135  (Cvt32to32F x) -> (CVTSL2SS x)
   136  (Cvt32to64F x) -> (CVTSL2SD x)
   137  (Cvt64to32F x) -> (CVTSQ2SS x)
   138  (Cvt64to64F x) -> (CVTSQ2SD x)
   139  
   140  (Cvt32Fto32 x) -> (CVTTSS2SL x)
   141  (Cvt32Fto64 x) -> (CVTTSS2SQ x)
   142  (Cvt64Fto32 x) -> (CVTTSD2SL x)
   143  (Cvt64Fto64 x) -> (CVTTSD2SQ x)
   144  
   145  (Cvt32Fto64F x) -> (CVTSS2SD x)
   146  (Cvt64Fto32F x) -> (CVTSD2SS x)
   147  
   148  // Lowering shifts
   149  // Unsigned shifts need to return 0 if shift amount is >= width of shifted value.
   150  //   result = (arg << shift) & (shift >= argbits ? 0 : 0xffffffffffffffff)
   151  (Lsh64x64 <t> x y) -> (ANDQ (SHLQ <t> x y) (SBBQcarrymask <t> (CMPQconst y [64])))
   152  (Lsh64x32 <t> x y) -> (ANDQ (SHLQ <t> x y) (SBBQcarrymask <t> (CMPLconst y [64])))
   153  (Lsh64x16 <t> x y) -> (ANDQ (SHLQ <t> x y) (SBBQcarrymask <t> (CMPWconst y [64])))
   154  (Lsh64x8  <t> x y) -> (ANDQ (SHLQ <t> x y) (SBBQcarrymask <t> (CMPBconst y [64])))
   155  
   156  (Lsh32x64 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPQconst y [32])))
   157  (Lsh32x32 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPLconst y [32])))
   158  (Lsh32x16 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPWconst y [32])))
   159  (Lsh32x8  <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPBconst y [32])))
   160  
   161  (Lsh16x64 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPQconst y [32])))
   162  (Lsh16x32 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPLconst y [32])))
   163  (Lsh16x16 <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPWconst y [32])))
   164  (Lsh16x8  <t> x y) -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPBconst y [32])))
   165  
   166  (Lsh8x64 <t> x y)  -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPQconst y [32])))
   167  (Lsh8x32 <t> x y)  -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPLconst y [32])))
   168  (Lsh8x16 <t> x y)  -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPWconst y [32])))
   169  (Lsh8x8  <t> x y)  -> (ANDL (SHLL <t> x y) (SBBLcarrymask <t> (CMPBconst y [32])))
   170  
   171  (Lrot64 <t> x [c]) -> (ROLQconst <t> [c&63] x)
   172  (Lrot32 <t> x [c]) -> (ROLLconst <t> [c&31] x)
   173  (Lrot16 <t> x [c]) -> (ROLWconst <t> [c&15] x)
   174  (Lrot8  <t> x [c]) -> (ROLBconst <t> [c&7] x)
   175  
   176  (Rsh64Ux64 <t> x y) -> (ANDQ (SHRQ <t> x y) (SBBQcarrymask <t> (CMPQconst y [64])))
   177  (Rsh64Ux32 <t> x y) -> (ANDQ (SHRQ <t> x y) (SBBQcarrymask <t> (CMPLconst y [64])))
   178  (Rsh64Ux16 <t> x y) -> (ANDQ (SHRQ <t> x y) (SBBQcarrymask <t> (CMPWconst y [64])))
   179  (Rsh64Ux8  <t> x y) -> (ANDQ (SHRQ <t> x y) (SBBQcarrymask <t> (CMPBconst y [64])))
   180  
   181  (Rsh32Ux64 <t> x y) -> (ANDL (SHRL <t> x y) (SBBLcarrymask <t> (CMPQconst y [32])))
   182  (Rsh32Ux32 <t> x y) -> (ANDL (SHRL <t> x y) (SBBLcarrymask <t> (CMPLconst y [32])))
   183  (Rsh32Ux16 <t> x y) -> (ANDL (SHRL <t> x y) (SBBLcarrymask <t> (CMPWconst y [32])))
   184  (Rsh32Ux8  <t> x y) -> (ANDL (SHRL <t> x y) (SBBLcarrymask <t> (CMPBconst y [32])))
   185  
   186  (Rsh16Ux64 <t> x y) -> (ANDL (SHRW <t> x y) (SBBLcarrymask <t> (CMPQconst y [16])))
   187  (Rsh16Ux32 <t> x y) -> (ANDL (SHRW <t> x y) (SBBLcarrymask <t> (CMPLconst y [16])))
   188  (Rsh16Ux16 <t> x y) -> (ANDL (SHRW <t> x y) (SBBLcarrymask <t> (CMPWconst y [16])))
   189  (Rsh16Ux8  <t> x y) -> (ANDL (SHRW <t> x y) (SBBLcarrymask <t> (CMPBconst y [16])))
   190  
   191  (Rsh8Ux64 <t> x y)  -> (ANDL (SHRB <t> x y) (SBBLcarrymask <t> (CMPQconst y [8])))
   192  (Rsh8Ux32 <t> x y)  -> (ANDL (SHRB <t> x y) (SBBLcarrymask <t> (CMPLconst y [8])))
   193  (Rsh8Ux16 <t> x y)  -> (ANDL (SHRB <t> x y) (SBBLcarrymask <t> (CMPWconst y [8])))
   194  (Rsh8Ux8  <t> x y)  -> (ANDL (SHRB <t> x y) (SBBLcarrymask <t> (CMPBconst y [8])))
   195  
   196  // Signed right shift needs to return 0/-1 if shift amount is >= width of shifted value.
   197  // We implement this by setting the shift value to -1 (all ones) if the shift value is >= width.
   198  (Rsh64x64 <t> x y) -> (SARQ <t> x (ORQ <y.Type> y (NOTQ <y.Type> (SBBQcarrymask <y.Type> (CMPQconst y [64])))))
   199  (Rsh64x32 <t> x y) -> (SARQ <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPLconst y [64])))))
   200  (Rsh64x16 <t> x y) -> (SARQ <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPWconst y [64])))))
   201  (Rsh64x8  <t> x y) -> (SARQ <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPBconst y [64])))))
   202  
   203  (Rsh32x64 <t> x y) -> (SARL <t> x (ORQ <y.Type> y (NOTQ <y.Type> (SBBQcarrymask <y.Type> (CMPQconst y [32])))))
   204  (Rsh32x32 <t> x y) -> (SARL <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPLconst y [32])))))
   205  (Rsh32x16 <t> x y) -> (SARL <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPWconst y [32])))))
   206  (Rsh32x8  <t> x y) -> (SARL <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPBconst y [32])))))
   207  
   208  (Rsh16x64 <t> x y) -> (SARW <t> x (ORQ <y.Type> y (NOTQ <y.Type> (SBBQcarrymask <y.Type> (CMPQconst y [16])))))
   209  (Rsh16x32 <t> x y) -> (SARW <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPLconst y [16])))))
   210  (Rsh16x16 <t> x y) -> (SARW <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPWconst y [16])))))
   211  (Rsh16x8  <t> x y) -> (SARW <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPBconst y [16])))))
   212  
   213  (Rsh8x64 <t> x y)  -> (SARB <t> x (ORQ <y.Type> y (NOTQ <y.Type> (SBBQcarrymask <y.Type> (CMPQconst y [8])))))
   214  (Rsh8x32 <t> x y)  -> (SARB <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPLconst y [8])))))
   215  (Rsh8x16 <t> x y)  -> (SARB <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPWconst y [8])))))
   216  (Rsh8x8  <t> x y)  -> (SARB <t> x (ORL <y.Type> y (NOTL <y.Type> (SBBLcarrymask <y.Type> (CMPBconst y [8])))))
   217  
   218  // Lowering comparisons
   219  (Less64  x y) -> (SETL (CMPQ x y))
   220  (Less32  x y) -> (SETL (CMPL x y))
   221  (Less16  x y) -> (SETL (CMPW x y))
   222  (Less8   x y) -> (SETL (CMPB x y))
   223  (Less64U x y) -> (SETB (CMPQ x y))
   224  (Less32U x y) -> (SETB (CMPL x y))
   225  (Less16U x y) -> (SETB (CMPW x y))
   226  (Less8U  x y) -> (SETB (CMPB x y))
   227  // Use SETGF with reversed operands to dodge NaN case
   228  (Less64F x y) -> (SETGF (UCOMISD y x))
   229  (Less32F x y) -> (SETGF (UCOMISS y x))
   230  
   231  (Leq64  x y) -> (SETLE (CMPQ x y))
   232  (Leq32  x y) -> (SETLE (CMPL x y))
   233  (Leq16  x y) -> (SETLE (CMPW x y))
   234  (Leq8   x y) -> (SETLE (CMPB x y))
   235  (Leq64U x y) -> (SETBE (CMPQ x y))
   236  (Leq32U x y) -> (SETBE (CMPL x y))
   237  (Leq16U x y) -> (SETBE (CMPW x y))
   238  (Leq8U  x y) -> (SETBE (CMPB x y))
   239  // Use SETGEF with reversed operands to dodge NaN case
   240  (Leq64F x y) -> (SETGEF (UCOMISD y x))
   241  (Leq32F x y) -> (SETGEF (UCOMISS y x))
   242  
   243  (Greater64  x y) -> (SETG (CMPQ x y))
   244  (Greater32  x y) -> (SETG (CMPL x y))
   245  (Greater16  x y) -> (SETG (CMPW x y))
   246  (Greater8   x y) -> (SETG (CMPB x y))
   247  (Greater64U x y) -> (SETA (CMPQ x y))
   248  (Greater32U x y) -> (SETA (CMPL x y))
   249  (Greater16U x y) -> (SETA (CMPW x y))
   250  (Greater8U  x y) -> (SETA (CMPB x y))
   251  // Note Go assembler gets UCOMISx operand order wrong, but it is right here
   252  // Bug is accommodated at generation of assembly language.
   253  (Greater64F x y) -> (SETGF (UCOMISD x y))
   254  (Greater32F x y) -> (SETGF (UCOMISS x y))
   255  
   256  (Geq64  x y) -> (SETGE (CMPQ x y))
   257  (Geq32  x y) -> (SETGE (CMPL x y))
   258  (Geq16  x y) -> (SETGE (CMPW x y))
   259  (Geq8   x y) -> (SETGE (CMPB x y))
   260  (Geq64U x y) -> (SETAE (CMPQ x y))
   261  (Geq32U x y) -> (SETAE (CMPL x y))
   262  (Geq16U x y) -> (SETAE (CMPW x y))
   263  (Geq8U  x y) -> (SETAE (CMPB x y))
   264  // Note Go assembler gets UCOMISx operand order wrong, but it is right here
   265  // Bug is accommodated at generation of assembly language.
   266  (Geq64F x y) -> (SETGEF (UCOMISD x y))
   267  (Geq32F x y) -> (SETGEF (UCOMISS x y))
   268  
   269  (Eq64  x y) -> (SETEQ (CMPQ x y))
   270  (Eq32  x y) -> (SETEQ (CMPL x y))
   271  (Eq16  x y) -> (SETEQ (CMPW x y))
   272  (Eq8   x y) -> (SETEQ (CMPB x y))
   273  (EqB   x y) -> (SETEQ (CMPB x y))
   274  (EqPtr x y) && config.PtrSize == 8 -> (SETEQ (CMPQ x y))
   275  (EqPtr x y) && config.PtrSize == 4 -> (SETEQ (CMPL x y))
   276  (Eq64F x y) -> (SETEQF (UCOMISD x y))
   277  (Eq32F x y) -> (SETEQF (UCOMISS x y))
   278  
   279  (Neq64  x y) -> (SETNE (CMPQ x y))
   280  (Neq32  x y) -> (SETNE (CMPL x y))
   281  (Neq16  x y) -> (SETNE (CMPW x y))
   282  (Neq8   x y) -> (SETNE (CMPB x y))
   283  (NeqB   x y) -> (SETNE (CMPB x y))
   284  (NeqPtr x y) && config.PtrSize == 8 -> (SETNE (CMPQ x y))
   285  (NeqPtr x y) && config.PtrSize == 4 -> (SETNE (CMPL x y))
   286  (Neq64F x y) -> (SETNEF (UCOMISD x y))
   287  (Neq32F x y) -> (SETNEF (UCOMISS x y))
   288  
   289  (Int64Hi x) -> (SHRQconst [32] x) // needed for amd64p32
   290  
   291  // Lowering loads
   292  (Load <t> ptr mem) && (is64BitInt(t) || isPtr(t) && config.PtrSize == 8) -> (MOVQload ptr mem)
   293  (Load <t> ptr mem) && (is32BitInt(t) || isPtr(t) && config.PtrSize == 4) -> (MOVLload ptr mem)
   294  (Load <t> ptr mem) && is16BitInt(t) -> (MOVWload ptr mem)
   295  (Load <t> ptr mem) && (t.IsBoolean() || is8BitInt(t)) -> (MOVBload ptr mem)
   296  (Load <t> ptr mem) && is32BitFloat(t) -> (MOVSSload ptr mem)
   297  (Load <t> ptr mem) && is64BitFloat(t) -> (MOVSDload ptr mem)
   298  
   299  // Lowering stores
   300  // These more-specific FP versions of Store pattern should come first.
   301  (Store [8] ptr val mem) && is64BitFloat(val.Type) -> (MOVSDstore ptr val mem)
   302  (Store [4] ptr val mem) && is32BitFloat(val.Type) -> (MOVSSstore ptr val mem)
   303  
   304  (Store [8] ptr val mem) -> (MOVQstore ptr val mem)
   305  (Store [4] ptr val mem) -> (MOVLstore ptr val mem)
   306  (Store [2] ptr val mem) -> (MOVWstore ptr val mem)
   307  (Store [1] ptr val mem) -> (MOVBstore ptr val mem)
   308  
   309  // Lowering moves
   310  (Move [s] _ _ mem) && SizeAndAlign(s).Size() == 0 -> mem
   311  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 1 -> (MOVBstore dst (MOVBload src mem) mem)
   312  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 2 -> (MOVWstore dst (MOVWload src mem) mem)
   313  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 4 -> (MOVLstore dst (MOVLload src mem) mem)
   314  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 8 -> (MOVQstore dst (MOVQload src mem) mem)
   315  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 16 -> (MOVOstore dst (MOVOload src mem) mem)
   316  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 3 ->
   317  	(MOVBstore [2] dst (MOVBload [2] src mem)
   318  		(MOVWstore dst (MOVWload src mem) mem))
   319  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 5 ->
   320  	(MOVBstore [4] dst (MOVBload [4] src mem)
   321  		(MOVLstore dst (MOVLload src mem) mem))
   322  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 6 ->
   323  	(MOVWstore [4] dst (MOVWload [4] src mem)
   324  		(MOVLstore dst (MOVLload src mem) mem))
   325  (Move [s] dst src mem) && SizeAndAlign(s).Size() == 7 ->
   326  	(MOVLstore [3] dst (MOVLload [3] src mem)
   327  		(MOVLstore dst (MOVLload src mem) mem))
   328  (Move [s] dst src mem) && SizeAndAlign(s).Size() > 8 && SizeAndAlign(s).Size() < 16 ->
   329  	(MOVQstore [SizeAndAlign(s).Size()-8] dst (MOVQload [SizeAndAlign(s).Size()-8] src mem)
   330  		(MOVQstore dst (MOVQload src mem) mem))
   331  
   332  // Adjust moves to be a multiple of 16 bytes.
   333  (Move [s] dst src mem)
   334  	&& SizeAndAlign(s).Size() > 16 && SizeAndAlign(s).Size()%16 != 0 && SizeAndAlign(s).Size()%16 <= 8 ->
   335  	(Move [SizeAndAlign(s).Size()-SizeAndAlign(s).Size()%16]
   336  		(OffPtr <dst.Type> dst [SizeAndAlign(s).Size()%16])
   337  		(OffPtr <src.Type> src [SizeAndAlign(s).Size()%16])
   338  		(MOVQstore dst (MOVQload src mem) mem))
   339  (Move [s] dst src mem)
   340  	&& SizeAndAlign(s).Size() > 16 && SizeAndAlign(s).Size()%16 != 0 && SizeAndAlign(s).Size()%16 > 8 ->
   341  	(Move [SizeAndAlign(s).Size()-SizeAndAlign(s).Size()%16]
   342  		(OffPtr <dst.Type> dst [SizeAndAlign(s).Size()%16])
   343  		(OffPtr <src.Type> src [SizeAndAlign(s).Size()%16])
   344  		(MOVOstore dst (MOVOload src mem) mem))
   345  
   346  // Medium copying uses a duff device.
   347  (Move [s] dst src mem)
   348  	&& SizeAndAlign(s).Size() >= 32 && SizeAndAlign(s).Size() <= 16*64 && SizeAndAlign(s).Size()%16 == 0
   349  	&& !config.noDuffDevice ->
   350  	(DUFFCOPY [14*(64-SizeAndAlign(s).Size()/16)] dst src mem)
   351  // 14 and 64 are magic constants.  14 is the number of bytes to encode:
   352  //	MOVUPS	(SI), X0
   353  //	ADDQ	$16, SI
   354  //	MOVUPS	X0, (DI)
   355  //	ADDQ	$16, DI
   356  // and 64 is the number of such blocks. See src/runtime/duff_amd64.s:duffcopy.
   357  
   358  // Large copying uses REP MOVSQ.
   359  (Move [s] dst src mem) && (SizeAndAlign(s).Size() > 16*64 || config.noDuffDevice) && SizeAndAlign(s).Size()%8 == 0 ->
   360  	(REPMOVSQ dst src (MOVQconst [SizeAndAlign(s).Size()/8]) mem)
   361  
   362  // Lowering Zero instructions
   363  (Zero [s] _ mem) && SizeAndAlign(s).Size() == 0 -> mem
   364  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 1 -> (MOVBstoreconst [0] destptr mem)
   365  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 2 -> (MOVWstoreconst [0] destptr mem)
   366  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 4 -> (MOVLstoreconst [0] destptr mem)
   367  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 8 -> (MOVQstoreconst [0] destptr mem)
   368  
   369  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 3 ->
   370  	(MOVBstoreconst [makeValAndOff(0,2)] destptr
   371  		(MOVWstoreconst [0] destptr mem))
   372  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 5 ->
   373  	(MOVBstoreconst [makeValAndOff(0,4)] destptr
   374  		(MOVLstoreconst [0] destptr mem))
   375  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 6 ->
   376  	(MOVWstoreconst [makeValAndOff(0,4)] destptr
   377  		(MOVLstoreconst [0] destptr mem))
   378  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 7 ->
   379  	(MOVLstoreconst [makeValAndOff(0,3)] destptr
   380  		(MOVLstoreconst [0] destptr mem))
   381  
   382  // Strip off any fractional word zeroing.
   383  (Zero [s] destptr mem) && SizeAndAlign(s).Size()%8 != 0 && SizeAndAlign(s).Size() > 8 ->
   384  	(Zero [SizeAndAlign(s).Size()-SizeAndAlign(s).Size()%8] (OffPtr <destptr.Type> destptr [SizeAndAlign(s).Size()%8])
   385  		(MOVQstoreconst [0] destptr mem))
   386  
   387  // Zero small numbers of words directly.
   388  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 16 ->
   389  	(MOVQstoreconst [makeValAndOff(0,8)] destptr
   390  		(MOVQstoreconst [0] destptr mem))
   391  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 24 ->
   392  	(MOVQstoreconst [makeValAndOff(0,16)] destptr
   393  		(MOVQstoreconst [makeValAndOff(0,8)] destptr
   394  			(MOVQstoreconst [0] destptr mem)))
   395  (Zero [s] destptr mem) && SizeAndAlign(s).Size() == 32 ->
   396  	(MOVQstoreconst [makeValAndOff(0,24)] destptr
   397  		(MOVQstoreconst [makeValAndOff(0,16)] destptr
   398  			(MOVQstoreconst [makeValAndOff(0,8)] destptr
   399  				(MOVQstoreconst [0] destptr mem))))
   400  
   401  // Medium zeroing uses a duff device.
   402  (Zero [s] destptr mem)
   403  	&& SizeAndAlign(s).Size() <= 1024 && SizeAndAlign(s).Size()%8 == 0 && SizeAndAlign(s).Size()%16 != 0
   404  	&& !config.noDuffDevice ->
   405  	(Zero [SizeAndAlign(s).Size()-8] (OffPtr <destptr.Type> [8] destptr) (MOVQstore destptr (MOVQconst [0]) mem))
   406  (Zero [s] destptr mem)
   407  	&& SizeAndAlign(s).Size() <= 1024 && SizeAndAlign(s).Size()%16 == 0 && !config.noDuffDevice ->
   408  	(DUFFZERO [SizeAndAlign(s).Size()] destptr (MOVOconst [0]) mem)
   409  
   410  // Large zeroing uses REP STOSQ.
   411  (Zero [s] destptr mem)
   412  	&& (SizeAndAlign(s).Size() > 1024 || (config.noDuffDevice && SizeAndAlign(s).Size() > 32))
   413  	&& SizeAndAlign(s).Size()%8 == 0 ->
   414  	(REPSTOSQ destptr (MOVQconst [SizeAndAlign(s).Size()/8]) (MOVQconst [0]) mem)
   415  
   416  // Lowering constants
   417  (Const8   [val]) -> (MOVLconst [val])
   418  (Const16  [val]) -> (MOVLconst [val])
   419  (Const32  [val]) -> (MOVLconst [val])
   420  (Const64  [val]) -> (MOVQconst [val])
   421  (Const32F [val]) -> (MOVSSconst [val])
   422  (Const64F [val]) -> (MOVSDconst [val])
   423  (ConstNil) && config.PtrSize == 8 -> (MOVQconst [0])
   424  (ConstNil) && config.PtrSize == 4 -> (MOVLconst [0])
   425  (ConstBool [b]) -> (MOVLconst [b])
   426  
   427  // Lowering calls
   428  (StaticCall [argwid] {target} mem) -> (CALLstatic [argwid] {target} mem)
   429  (ClosureCall [argwid] entry closure mem) -> (CALLclosure [argwid] entry closure mem)
   430  (DeferCall [argwid] mem) -> (CALLdefer [argwid] mem)
   431  (GoCall [argwid] mem) -> (CALLgo [argwid] mem)
   432  (InterCall [argwid] entry mem) -> (CALLinter [argwid] entry mem)
   433  
   434  // Miscellaneous
   435  (Convert <t> x mem) && config.PtrSize == 8 -> (MOVQconvert <t> x mem)
   436  (Convert <t> x mem) && config.PtrSize == 4 -> (MOVLconvert <t> x mem)
   437  (IsNonNil p) && config.PtrSize == 8 -> (SETNE (TESTQ p p))
   438  (IsNonNil p) && config.PtrSize == 4 -> (SETNE (TESTL p p))
   439  (IsInBounds idx len) -> (SETB (CMPQ idx len))
   440  (IsSliceInBounds idx len) -> (SETBE (CMPQ idx len))
   441  (NilCheck ptr mem) -> (LoweredNilCheck ptr mem)
   442  (GetG mem) -> (LoweredGetG mem)
   443  (GetClosurePtr) -> (LoweredGetClosurePtr)
   444  (Addr {sym} base) && config.PtrSize == 8 -> (LEAQ {sym} base)
   445  (Addr {sym} base) && config.PtrSize == 4 -> (LEAL {sym} base)
   446  
   447  // block rewrites
   448  (If (SETL  cmp) yes no) -> (LT  cmp yes no)
   449  (If (SETLE cmp) yes no) -> (LE  cmp yes no)
   450  (If (SETG  cmp) yes no) -> (GT  cmp yes no)
   451  (If (SETGE cmp) yes no) -> (GE  cmp yes no)
   452  (If (SETEQ cmp) yes no) -> (EQ  cmp yes no)
   453  (If (SETNE cmp) yes no) -> (NE  cmp yes no)
   454  (If (SETB  cmp) yes no) -> (ULT cmp yes no)
   455  (If (SETBE cmp) yes no) -> (ULE cmp yes no)
   456  (If (SETA  cmp) yes no) -> (UGT cmp yes no)
   457  (If (SETAE cmp) yes no) -> (UGE cmp yes no)
   458  
   459  // Special case for floating point - LF/LEF not generated
   460  (If (SETGF  cmp) yes no) -> (UGT  cmp yes no)
   461  (If (SETGEF cmp) yes no) -> (UGE  cmp yes no)
   462  (If (SETEQF cmp) yes no) -> (EQF  cmp yes no)
   463  (If (SETNEF cmp) yes no) -> (NEF  cmp yes no)
   464  
   465  (If cond yes no) -> (NE (TESTB cond cond) yes no)
   466  
   467  // Atomic loads.  Other than preserving their ordering with respect to other loads, nothing special here.
   468  (AtomicLoad32 ptr mem) -> (MOVLatomicload ptr mem)
   469  (AtomicLoad64 ptr mem) -> (MOVQatomicload ptr mem)
   470  (AtomicLoadPtr ptr mem) && config.PtrSize == 8 -> (MOVQatomicload ptr mem)
   471  (AtomicLoadPtr ptr mem) && config.PtrSize == 4 -> (MOVLatomicload ptr mem)
   472  
   473  // Atomic stores.  We use XCHG to prevent the hardware reordering a subsequent load.
   474  // TODO: most runtime uses of atomic stores don't need that property.  Use normal stores for those?
   475  (AtomicStore32 ptr val mem) -> (Select1 (XCHGL <MakeTuple(config.Frontend().TypeUInt32(),TypeMem)> val ptr mem))
   476  (AtomicStore64 ptr val mem) -> (Select1 (XCHGQ <MakeTuple(config.Frontend().TypeUInt64(),TypeMem)> val ptr mem))
   477  (AtomicStorePtrNoWB ptr val mem) && config.PtrSize == 8 -> (Select1 (XCHGQ <MakeTuple(config.Frontend().TypeBytePtr(),TypeMem)> val ptr mem))
   478  (AtomicStorePtrNoWB ptr val mem) && config.PtrSize == 4 -> (Select1 (XCHGL <MakeTuple(config.Frontend().TypeBytePtr(),TypeMem)> val ptr mem))
   479  
   480  // Atomic exchanges.
   481  (AtomicExchange32 ptr val mem) -> (XCHGL val ptr mem)
   482  (AtomicExchange64 ptr val mem) -> (XCHGQ val ptr mem)
   483  
   484  // Atomic adds.
   485  (AtomicAdd32 ptr val mem) -> (AddTupleFirst32 (XADDLlock val ptr mem) val)
   486  (AtomicAdd64 ptr val mem) -> (AddTupleFirst64 (XADDQlock val ptr mem) val)
   487  (Select0 <t> (AddTupleFirst32 tuple val)) -> (ADDL val (Select0 <t> tuple))
   488  (Select1     (AddTupleFirst32 tuple _  )) -> (Select1 tuple)
   489  (Select0 <t> (AddTupleFirst64 tuple val)) -> (ADDQ val (Select0 <t> tuple))
   490  (Select1     (AddTupleFirst64 tuple _  )) -> (Select1 tuple)
   491  
   492  // Atomic compare and swap.
   493  (AtomicCompareAndSwap32 ptr old new_ mem) -> (CMPXCHGLlock ptr old new_ mem)
   494  (AtomicCompareAndSwap64 ptr old new_ mem) -> (CMPXCHGQlock ptr old new_ mem)
   495  
   496  // Atomic memory updates.
   497  (AtomicAnd8 ptr val mem) -> (ANDBlock ptr val mem)
   498  (AtomicOr8 ptr val mem) -> (ORBlock ptr val mem)
   499  
   500  // ***************************
   501  // Above: lowering rules
   502  // Below: optimizations
   503  // ***************************
   504  // TODO: Should the optimizations be a separate pass?
   505  
   506  // Fold boolean tests into blocks
   507  (NE (TESTB (SETL  cmp) (SETL  cmp)) yes no) -> (LT  cmp yes no)
   508  (NE (TESTB (SETLE cmp) (SETLE cmp)) yes no) -> (LE  cmp yes no)
   509  (NE (TESTB (SETG  cmp) (SETG  cmp)) yes no) -> (GT  cmp yes no)
   510  (NE (TESTB (SETGE cmp) (SETGE cmp)) yes no) -> (GE  cmp yes no)
   511  (NE (TESTB (SETEQ cmp) (SETEQ cmp)) yes no) -> (EQ  cmp yes no)
   512  (NE (TESTB (SETNE cmp) (SETNE cmp)) yes no) -> (NE  cmp yes no)
   513  (NE (TESTB (SETB  cmp) (SETB  cmp)) yes no) -> (ULT cmp yes no)
   514  (NE (TESTB (SETBE cmp) (SETBE cmp)) yes no) -> (ULE cmp yes no)
   515  (NE (TESTB (SETA  cmp) (SETA  cmp)) yes no) -> (UGT cmp yes no)
   516  (NE (TESTB (SETAE cmp) (SETAE cmp)) yes no) -> (UGE cmp yes no)
   517  
   518  // Special case for floating point - LF/LEF not generated
   519  (NE (TESTB (SETGF  cmp) (SETGF  cmp)) yes no) -> (UGT  cmp yes no)
   520  (NE (TESTB (SETGEF cmp) (SETGEF cmp)) yes no) -> (UGE  cmp yes no)
   521  (NE (TESTB (SETEQF cmp) (SETEQF cmp)) yes no) -> (EQF  cmp yes no)
   522  (NE (TESTB (SETNEF cmp) (SETNEF cmp)) yes no) -> (NEF  cmp yes no)
   523  
   524  // Disabled because it interferes with the pattern match above and makes worse code.
   525  // (SETNEF x) -> (ORQ (SETNE <config.Frontend().TypeInt8()> x) (SETNAN <config.Frontend().TypeInt8()> x))
   526  // (SETEQF x) -> (ANDQ (SETEQ <config.Frontend().TypeInt8()> x) (SETORD <config.Frontend().TypeInt8()> x))
   527  
   528  // fold constants into instructions
   529  (ADDQ x (MOVQconst [c])) && is32Bit(c) -> (ADDQconst [c] x)
   530  (ADDQ (MOVQconst [c]) x) && is32Bit(c) -> (ADDQconst [c] x)
   531  (ADDL x (MOVLconst [c])) -> (ADDLconst [c] x)
   532  (ADDL (MOVLconst [c]) x) -> (ADDLconst [c] x)
   533  
   534  (SUBQ x (MOVQconst [c])) && is32Bit(c) -> (SUBQconst x [c])
   535  (SUBQ (MOVQconst [c]) x) && is32Bit(c) -> (NEGQ (SUBQconst <v.Type> x [c]))
   536  (SUBL x (MOVLconst [c])) -> (SUBLconst x [c])
   537  (SUBL (MOVLconst [c]) x) -> (NEGL (SUBLconst <v.Type> x [c]))
   538  
   539  (MULQ x (MOVQconst [c])) && is32Bit(c) -> (MULQconst [c] x)
   540  (MULQ (MOVQconst [c]) x) && is32Bit(c) -> (MULQconst [c] x)
   541  (MULL x (MOVLconst [c])) -> (MULLconst [c] x)
   542  (MULL (MOVLconst [c]) x) -> (MULLconst [c] x)
   543  
   544  (ANDQ x (MOVQconst [c])) && is32Bit(c) -> (ANDQconst [c] x)
   545  (ANDQ (MOVQconst [c]) x) && is32Bit(c) -> (ANDQconst [c] x)
   546  (ANDL x (MOVLconst [c])) -> (ANDLconst [c] x)
   547  (ANDL (MOVLconst [c]) x) -> (ANDLconst [c] x)
   548  
   549  (ANDLconst [c] (ANDLconst [d] x)) -> (ANDLconst [c & d] x)
   550  (ANDQconst [c] (ANDQconst [d] x)) -> (ANDQconst [c & d] x)
   551  
   552  (XORLconst [c] (XORLconst [d] x)) -> (XORLconst [c ^ d] x)
   553  (XORQconst [c] (XORQconst [d] x)) -> (XORQconst [c ^ d] x)
   554  
   555  (MULLconst [c] (MULLconst [d] x)) -> (MULLconst [int64(int32(c * d))] x)
   556  (MULQconst [c] (MULQconst [d] x)) && is32Bit(c*d) -> (MULQconst [c * d] x)
   557  
   558  (ORQ x (MOVQconst [c])) && is32Bit(c) -> (ORQconst [c] x)
   559  (ORQ (MOVQconst [c]) x) && is32Bit(c) -> (ORQconst [c] x)
   560  (ORL x (MOVLconst [c])) -> (ORLconst [c] x)
   561  (ORL (MOVLconst [c]) x) -> (ORLconst [c] x)
   562  
   563  (XORQ x (MOVQconst [c])) && is32Bit(c) -> (XORQconst [c] x)
   564  (XORQ (MOVQconst [c]) x) && is32Bit(c) -> (XORQconst [c] x)
   565  (XORL x (MOVLconst [c])) -> (XORLconst [c] x)
   566  (XORL (MOVLconst [c]) x) -> (XORLconst [c] x)
   567  
   568  (SHLQ x (MOVQconst [c])) -> (SHLQconst [c&63] x)
   569  (SHLQ x (MOVLconst [c])) -> (SHLQconst [c&63] x)
   570  
   571  (SHLL x (MOVQconst [c])) -> (SHLLconst [c&31] x)
   572  (SHLL x (MOVLconst [c])) -> (SHLLconst [c&31] x)
   573  
   574  (SHRQ x (MOVQconst [c])) -> (SHRQconst [c&63] x)
   575  (SHRQ x (MOVLconst [c])) -> (SHRQconst [c&63] x)
   576  
   577  (SHRL x (MOVQconst [c])) -> (SHRLconst [c&31] x)
   578  (SHRL x (MOVLconst [c])) -> (SHRLconst [c&31] x)
   579  
   580  (SHRW x (MOVQconst [c])) -> (SHRWconst [c&31] x)
   581  (SHRW x (MOVLconst [c])) -> (SHRWconst [c&31] x)
   582  
   583  (SHRB x (MOVQconst [c])) -> (SHRBconst [c&31] x)
   584  (SHRB x (MOVLconst [c])) -> (SHRBconst [c&31] x)
   585  
   586  (SARQ x (MOVQconst [c])) -> (SARQconst [c&63] x)
   587  (SARQ x (MOVLconst [c])) -> (SARQconst [c&63] x)
   588  
   589  (SARL x (MOVQconst [c])) -> (SARLconst [c&31] x)
   590  (SARL x (MOVLconst [c])) -> (SARLconst [c&31] x)
   591  
   592  (SARW x (MOVQconst [c])) -> (SARWconst [c&31] x)
   593  (SARW x (MOVLconst [c])) -> (SARWconst [c&31] x)
   594  
   595  (SARB x (MOVQconst [c])) -> (SARBconst [c&31] x)
   596  (SARB x (MOVLconst [c])) -> (SARBconst [c&31] x)
   597  
   598  (SARL x (ANDLconst [31] y)) -> (SARL x y)
   599  (SARQ x (ANDQconst [63] y)) -> (SARQ x y)
   600  
   601  (SHLL x (ANDLconst [31] y)) -> (SHLL x y)
   602  (SHLQ x (ANDQconst [63] y)) -> (SHLQ x y)
   603  
   604  (SHRL x (ANDLconst [31] y)) -> (SHRL x y)
   605  (SHRQ x (ANDQconst [63] y)) -> (SHRQ x y)
   606  
   607  (ROLQconst [c] (ROLQconst [d] x)) -> (ROLQconst [(c+d)&63] x)
   608  (ROLLconst [c] (ROLLconst [d] x)) -> (ROLLconst [(c+d)&31] x)
   609  (ROLWconst [c] (ROLWconst [d] x)) -> (ROLWconst [(c+d)&15] x)
   610  (ROLBconst [c] (ROLBconst [d] x)) -> (ROLBconst [(c+d)& 7] x)
   611  
   612  (ROLQconst [0] x) -> x
   613  (ROLLconst [0] x) -> x
   614  (ROLWconst [0] x) -> x
   615  (ROLBconst [0] x) -> x
   616  
   617  // Note: the word and byte shifts keep the low 5 bits (not the low 4 or 3 bits)
   618  // because the x86 instructions are defined to use all 5 bits of the shift even
   619  // for the small shifts. I don't think we'll ever generate a weird shift (e.g.
   620  // (SHRW x (MOVLconst [24])), but just in case.
   621  
   622  (CMPQ x (MOVQconst [c])) && is32Bit(c) -> (CMPQconst x [c])
   623  (CMPQ (MOVQconst [c]) x) && is32Bit(c) -> (InvertFlags (CMPQconst x [c]))
   624  (CMPL x (MOVLconst [c])) -> (CMPLconst x [c])
   625  (CMPL (MOVLconst [c]) x) -> (InvertFlags (CMPLconst x [c]))
   626  (CMPW x (MOVLconst [c])) -> (CMPWconst x [int64(int16(c))])
   627  (CMPW (MOVLconst [c]) x) -> (InvertFlags (CMPWconst x [int64(int16(c))]))
   628  (CMPB x (MOVLconst [c])) -> (CMPBconst x [int64(int8(c))])
   629  (CMPB (MOVLconst [c]) x) -> (InvertFlags (CMPBconst x [int64(int8(c))]))
   630  
   631  // Using MOVBQZX instead of ANDQ is cheaper.
   632  (ANDQconst [0xFF] x) -> (MOVBQZX x)
   633  (ANDQconst [0xFFFF] x) -> (MOVWQZX x)
   634  (ANDQconst [0xFFFFFFFF] x) -> (MOVLQZX x)
   635  
   636  // strength reduction
   637  // Assumes that the following costs from https://gmplib.org/~tege/x86-timing.pdf:
   638  //    1 - addq, shlq, leaq, negq
   639  //    3 - imulq
   640  // This limits the rewrites to two instructions.
   641  // TODO: 27, 81
   642  (MULQconst [-1] x) -> (NEGQ x)
   643  (MULQconst [0] _) -> (MOVQconst [0])
   644  (MULQconst [1] x) -> x
   645  (MULQconst [3] x) -> (LEAQ2 x x)
   646  (MULQconst [5] x) -> (LEAQ4 x x)
   647  (MULQconst [7] x) -> (LEAQ8 (NEGQ <v.Type> x) x)
   648  (MULQconst [9] x) -> (LEAQ8 x x)
   649  (MULQconst [11] x) -> (LEAQ2 x (LEAQ4 <v.Type> x x))
   650  (MULQconst [13] x) -> (LEAQ4 x (LEAQ2 <v.Type> x x))
   651  (MULQconst [21] x) -> (LEAQ4 x (LEAQ4 <v.Type> x x))
   652  (MULQconst [25] x) -> (LEAQ8 x (LEAQ2 <v.Type> x x))
   653  (MULQconst [37] x) -> (LEAQ4 x (LEAQ8 <v.Type> x x))
   654  (MULQconst [41] x) -> (LEAQ8 x (LEAQ4 <v.Type> x x))
   655  (MULQconst [73] x) -> (LEAQ8 x (LEAQ8 <v.Type> x x))
   656  
   657  (MULQconst [c] x) && isPowerOfTwo(c) -> (SHLQconst [log2(c)] x)
   658  (MULQconst [c] x) && isPowerOfTwo(c+1) && c >= 15 -> (SUBQ (SHLQconst <v.Type> [log2(c+1)] x) x)
   659  (MULQconst [c] x) && isPowerOfTwo(c-1) && c >= 17 -> (LEAQ1 (SHLQconst <v.Type> [log2(c-1)] x) x)
   660  (MULQconst [c] x) && isPowerOfTwo(c-2) && c >= 34 -> (LEAQ2 (SHLQconst <v.Type> [log2(c-2)] x) x)
   661  (MULQconst [c] x) && isPowerOfTwo(c-4) && c >= 68 -> (LEAQ4 (SHLQconst <v.Type> [log2(c-4)] x) x)
   662  (MULQconst [c] x) && isPowerOfTwo(c-8) && c >= 136 -> (LEAQ8 (SHLQconst <v.Type> [log2(c-8)] x) x)
   663  (MULQconst [c] x) && c%3 == 0 && isPowerOfTwo(c/3)-> (SHLQconst [log2(c/3)] (LEAQ2 <v.Type> x x))
   664  (MULQconst [c] x) && c%5 == 0 && isPowerOfTwo(c/5)-> (SHLQconst [log2(c/5)] (LEAQ4 <v.Type> x x))
   665  (MULQconst [c] x) && c%9 == 0 && isPowerOfTwo(c/9)-> (SHLQconst [log2(c/9)] (LEAQ8 <v.Type> x x))
   666  
   667  // combine add/shift into LEAQ
   668  (ADDQ x (SHLQconst [3] y)) -> (LEAQ8 x y)
   669  (ADDQ x (SHLQconst [2] y)) -> (LEAQ4 x y)
   670  (ADDQ x (SHLQconst [1] y)) -> (LEAQ2 x y)
   671  (ADDQ x (ADDQ y y)) -> (LEAQ2 x y)
   672  (ADDQ x (ADDQ x y)) -> (LEAQ2 y x)
   673  (ADDQ x (ADDQ y x)) -> (LEAQ2 y x)
   674  
   675  // combine ADDQ/ADDQconst into LEAQ1
   676  (ADDQconst [c] (ADDQ x y)) -> (LEAQ1 [c] x y)
   677  (ADDQ (ADDQconst [c] x) y) -> (LEAQ1 [c] x y)
   678  (ADDQ x (ADDQconst [c] y)) -> (LEAQ1 [c] x y)
   679  
   680  // fold ADDQ into LEAQ
   681  (ADDQconst [c] (LEAQ [d] {s} x)) && is32Bit(c+d) -> (LEAQ [c+d] {s} x)
   682  (LEAQ [c] {s} (ADDQconst [d] x)) && is32Bit(c+d) -> (LEAQ [c+d] {s} x)
   683  (LEAQ [c] {s} (ADDQ x y)) && x.Op != OpSB && y.Op != OpSB -> (LEAQ1 [c] {s} x y)
   684  (ADDQ x (LEAQ [c] {s} y)) && x.Op != OpSB && y.Op != OpSB -> (LEAQ1 [c] {s} x y)
   685  (ADDQ (LEAQ [c] {s} x) y) && x.Op != OpSB && y.Op != OpSB -> (LEAQ1 [c] {s} x y)
   686  
   687  // fold ADDQconst into LEAQx
   688  (ADDQconst [c] (LEAQ1 [d] {s} x y)) && is32Bit(c+d) -> (LEAQ1 [c+d] {s} x y)
   689  (ADDQconst [c] (LEAQ2 [d] {s} x y)) && is32Bit(c+d) -> (LEAQ2 [c+d] {s} x y)
   690  (ADDQconst [c] (LEAQ4 [d] {s} x y)) && is32Bit(c+d) -> (LEAQ4 [c+d] {s} x y)
   691  (ADDQconst [c] (LEAQ8 [d] {s} x y)) && is32Bit(c+d) -> (LEAQ8 [c+d] {s} x y)
   692  (LEAQ1 [c] {s} (ADDQconst [d] x) y) && is32Bit(c+d)   && x.Op != OpSB -> (LEAQ1 [c+d] {s} x y)
   693  (LEAQ1 [c] {s} x (ADDQconst [d] y)) && is32Bit(c+d)   && y.Op != OpSB -> (LEAQ1 [c+d] {s} x y)
   694  (LEAQ2 [c] {s} (ADDQconst [d] x) y) && is32Bit(c+d)   && x.Op != OpSB -> (LEAQ2 [c+d] {s} x y)
   695  (LEAQ2 [c] {s} x (ADDQconst [d] y)) && is32Bit(c+2*d) && y.Op != OpSB -> (LEAQ2 [c+2*d] {s} x y)
   696  (LEAQ4 [c] {s} (ADDQconst [d] x) y) && is32Bit(c+d)   && x.Op != OpSB -> (LEAQ4 [c+d] {s} x y)
   697  (LEAQ4 [c] {s} x (ADDQconst [d] y)) && is32Bit(c+4*d) && y.Op != OpSB -> (LEAQ4 [c+4*d] {s} x y)
   698  (LEAQ8 [c] {s} (ADDQconst [d] x) y) && is32Bit(c+d)   && x.Op != OpSB -> (LEAQ8 [c+d] {s} x y)
   699  (LEAQ8 [c] {s} x (ADDQconst [d] y)) && is32Bit(c+8*d) && y.Op != OpSB -> (LEAQ8 [c+8*d] {s} x y)
   700  
   701  // fold shifts into LEAQx
   702  (LEAQ1 [c] {s} x (SHLQconst [1] y)) -> (LEAQ2 [c] {s} x y)
   703  (LEAQ1 [c] {s} (SHLQconst [1] x) y) -> (LEAQ2 [c] {s} y x)
   704  (LEAQ1 [c] {s} x (SHLQconst [2] y)) -> (LEAQ4 [c] {s} x y)
   705  (LEAQ1 [c] {s} (SHLQconst [2] x) y) -> (LEAQ4 [c] {s} y x)
   706  (LEAQ1 [c] {s} x (SHLQconst [3] y)) -> (LEAQ8 [c] {s} x y)
   707  (LEAQ1 [c] {s} (SHLQconst [3] x) y) -> (LEAQ8 [c] {s} y x)
   708  
   709  (LEAQ2 [c] {s} x (SHLQconst [1] y)) -> (LEAQ4 [c] {s} x y)
   710  (LEAQ2 [c] {s} x (SHLQconst [2] y)) -> (LEAQ8 [c] {s} x y)
   711  (LEAQ4 [c] {s} x (SHLQconst [1] y)) -> (LEAQ8 [c] {s} x y)
   712  
   713  // reverse ordering of compare instruction
   714  (SETL (InvertFlags x)) -> (SETG x)
   715  (SETG (InvertFlags x)) -> (SETL x)
   716  (SETB (InvertFlags x)) -> (SETA x)
   717  (SETA (InvertFlags x)) -> (SETB x)
   718  (SETLE (InvertFlags x)) -> (SETGE x)
   719  (SETGE (InvertFlags x)) -> (SETLE x)
   720  (SETBE (InvertFlags x)) -> (SETAE x)
   721  (SETAE (InvertFlags x)) -> (SETBE x)
   722  (SETEQ (InvertFlags x)) -> (SETEQ x)
   723  (SETNE (InvertFlags x)) -> (SETNE x)
   724  
   725  // sign extended loads
   726  // Note: The combined instruction must end up in the same block
   727  // as the original load. If not, we end up making a value with
   728  // memory type live in two different blocks, which can lead to
   729  // multiple memory values alive simultaneously.
   730  // Make sure we don't combine these ops if the load has another use.
   731  // This prevents a single load from being split into multiple loads
   732  // which then might return different values.  See test/atomicload.go.
   733  (MOVBQSX x:(MOVBload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVBQSXload <v.Type> [off] {sym} ptr mem)
   734  (MOVBQZX x:(MOVBload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVBload <v.Type> [off] {sym} ptr mem)
   735  (MOVWQSX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWQSXload <v.Type> [off] {sym} ptr mem)
   736  (MOVWQZX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWload <v.Type> [off] {sym} ptr mem)
   737  (MOVLQSX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVLQSXload <v.Type> [off] {sym} ptr mem)
   738  (MOVLQZX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVLload <v.Type> [off] {sym} ptr mem)
   739  
   740  (MOVBQZX x:(MOVBloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVBloadidx1 <v.Type> [off] {sym} ptr idx mem)
   741  (MOVWQZX x:(MOVWloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWloadidx1 <v.Type> [off] {sym} ptr idx mem)
   742  (MOVWQZX x:(MOVWloadidx2 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWloadidx2 <v.Type> [off] {sym} ptr idx mem)
   743  (MOVLQZX x:(MOVLloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVLloadidx1 <v.Type> [off] {sym} ptr idx mem)
   744  (MOVLQZX x:(MOVLloadidx4 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVLloadidx4 <v.Type> [off] {sym} ptr idx mem)
   745  
   746  // replace load from same location as preceding store with copy
   747  (MOVBload [off] {sym} ptr (MOVBstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
   748  (MOVWload [off] {sym} ptr (MOVWstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
   749  (MOVLload [off] {sym} ptr (MOVLstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
   750  (MOVQload [off] {sym} ptr (MOVQstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
   751  
   752  // Fold extensions and ANDs together.
   753  (MOVBQZX (ANDLconst [c] x)) -> (ANDLconst [c & 0xff] x)
   754  (MOVWQZX (ANDLconst [c] x)) -> (ANDLconst [c & 0xffff] x)
   755  (MOVLQZX (ANDLconst [c] x)) -> (ANDLconst [c] x)
   756  (MOVBQSX (ANDLconst [c] x)) && c & 0x80 == 0 -> (ANDLconst [c & 0x7f] x)
   757  (MOVWQSX (ANDLconst [c] x)) && c & 0x8000 == 0 -> (ANDLconst [c & 0x7fff] x)
   758  (MOVLQSX (ANDLconst [c] x)) && c & 0x80000000 == 0 -> (ANDLconst [c & 0x7fffffff] x)
   759  
   760  // Don't extend before storing
   761  (MOVLstore [off] {sym} ptr (MOVLQSX x) mem) -> (MOVLstore [off] {sym} ptr x mem)
   762  (MOVWstore [off] {sym} ptr (MOVWQSX x) mem) -> (MOVWstore [off] {sym} ptr x mem)
   763  (MOVBstore [off] {sym} ptr (MOVBQSX x) mem) -> (MOVBstore [off] {sym} ptr x mem)
   764  (MOVLstore [off] {sym} ptr (MOVLQZX x) mem) -> (MOVLstore [off] {sym} ptr x mem)
   765  (MOVWstore [off] {sym} ptr (MOVWQZX x) mem) -> (MOVWstore [off] {sym} ptr x mem)
   766  (MOVBstore [off] {sym} ptr (MOVBQZX x) mem) -> (MOVBstore [off] {sym} ptr x mem)
   767  
   768  // fold constants into memory operations
   769  // Note that this is not always a good idea because if not all the uses of
   770  // the ADDQconst get eliminated, we still have to compute the ADDQconst and we now
   771  // have potentially two live values (ptr and (ADDQconst [off] ptr)) instead of one.
   772  // Nevertheless, let's do it!
   773  (MOVQload  [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVQload  [off1+off2] {sym} ptr mem)
   774  (MOVLload  [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVLload  [off1+off2] {sym} ptr mem)
   775  (MOVWload  [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVWload  [off1+off2] {sym} ptr mem)
   776  (MOVBload  [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVBload  [off1+off2] {sym} ptr mem)
   777  (MOVSSload [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVSSload [off1+off2] {sym} ptr mem)
   778  (MOVSDload [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVSDload [off1+off2] {sym} ptr mem)
   779  (MOVOload  [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVOload  [off1+off2] {sym} ptr mem)
   780  
   781  (MOVQstore  [off1] {sym} (ADDQconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVQstore  [off1+off2] {sym} ptr val mem)
   782  (MOVLstore  [off1] {sym} (ADDQconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVLstore  [off1+off2] {sym} ptr val mem)
   783  (MOVWstore  [off1] {sym} (ADDQconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVWstore  [off1+off2] {sym} ptr val mem)
   784  (MOVBstore  [off1] {sym} (ADDQconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVBstore  [off1+off2] {sym} ptr val mem)
   785  (MOVSSstore [off1] {sym} (ADDQconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVSSstore [off1+off2] {sym} ptr val mem)
   786  (MOVSDstore [off1] {sym} (ADDQconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVSDstore [off1+off2] {sym} ptr val mem)
   787  (MOVOstore  [off1] {sym} (ADDQconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVOstore  [off1+off2] {sym} ptr val mem)
   788  
   789  // Fold constants into stores.
   790  (MOVQstore [off] {sym} ptr (MOVQconst [c]) mem) && validValAndOff(c,off) ->
   791  	(MOVQstoreconst [makeValAndOff(c,off)] {sym} ptr mem)
   792  (MOVLstore [off] {sym} ptr (MOVLconst [c]) mem) && validOff(off) ->
   793  	(MOVLstoreconst [makeValAndOff(int64(int32(c)),off)] {sym} ptr mem)
   794  (MOVWstore [off] {sym} ptr (MOVLconst [c]) mem) && validOff(off) ->
   795  	(MOVWstoreconst [makeValAndOff(int64(int16(c)),off)] {sym} ptr mem)
   796  (MOVBstore [off] {sym} ptr (MOVLconst [c]) mem) && validOff(off) ->
   797  	(MOVBstoreconst [makeValAndOff(int64(int8(c)),off)] {sym} ptr mem)
   798  
   799  // Fold address offsets into constant stores.
   800  (MOVQstoreconst [sc] {s} (ADDQconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
   801  	(MOVQstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
   802  (MOVLstoreconst [sc] {s} (ADDQconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
   803  	(MOVLstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
   804  (MOVWstoreconst [sc] {s} (ADDQconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
   805  	(MOVWstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
   806  (MOVBstoreconst [sc] {s} (ADDQconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
   807  	(MOVBstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
   808  
   809  // We need to fold LEAQ into the MOVx ops so that the live variable analysis knows
   810  // what variables are being read/written by the ops.
   811  (MOVQload  [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   812  	(MOVQload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
   813  (MOVLload  [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   814  	(MOVLload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
   815  (MOVWload  [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   816  	(MOVWload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
   817  (MOVBload  [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   818  	(MOVBload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
   819  (MOVSSload [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   820  	(MOVSSload [off1+off2] {mergeSym(sym1,sym2)} base mem)
   821  (MOVSDload [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   822  	(MOVSDload [off1+off2] {mergeSym(sym1,sym2)} base mem)
   823  (MOVOload [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   824  	(MOVOload [off1+off2] {mergeSym(sym1,sym2)} base mem)
   825  
   826  (MOVBQSXload [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   827  	(MOVBQSXload [off1+off2] {mergeSym(sym1,sym2)} base mem)
   828  (MOVWQSXload [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   829  	(MOVWQSXload [off1+off2] {mergeSym(sym1,sym2)} base mem)
   830  (MOVLQSXload [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   831  	(MOVLQSXload [off1+off2] {mergeSym(sym1,sym2)} base mem)
   832  
   833  (MOVQstore  [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   834  	(MOVQstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
   835  (MOVLstore  [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   836  	(MOVLstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
   837  (MOVWstore  [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   838  	(MOVWstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
   839  (MOVBstore  [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   840  	(MOVBstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
   841  (MOVSSstore [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   842  	(MOVSSstore [off1+off2] {mergeSym(sym1,sym2)} base val mem)
   843  (MOVSDstore [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   844  	(MOVSDstore [off1+off2] {mergeSym(sym1,sym2)} base val mem)
   845  (MOVOstore [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   846  	(MOVOstore [off1+off2] {mergeSym(sym1,sym2)} base val mem)
   847  
   848  (MOVQstoreconst [sc] {sym1} (LEAQ [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off) ->
   849  	(MOVQstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
   850  (MOVLstoreconst [sc] {sym1} (LEAQ [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off) ->
   851  	(MOVLstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
   852  (MOVWstoreconst [sc] {sym1} (LEAQ [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off) ->
   853  	(MOVWstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
   854  (MOVBstoreconst [sc] {sym1} (LEAQ [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off) ->
   855  	(MOVBstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
   856  
   857  // generating indexed loads and stores
   858  (MOVBload [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   859  	(MOVBloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   860  (MOVWload [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   861  	(MOVWloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   862  (MOVWload [off1] {sym1} (LEAQ2 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   863  	(MOVWloadidx2 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   864  (MOVLload [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   865  	(MOVLloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   866  (MOVLload [off1] {sym1} (LEAQ4 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   867  	(MOVLloadidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   868  (MOVQload [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   869  	(MOVQloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   870  (MOVQload [off1] {sym1} (LEAQ8 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   871  	(MOVQloadidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   872  (MOVSSload [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   873  	(MOVSSloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   874  (MOVSSload [off1] {sym1} (LEAQ4 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   875  	(MOVSSloadidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   876  (MOVSDload [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   877  	(MOVSDloadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   878  (MOVSDload [off1] {sym1} (LEAQ8 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   879  	(MOVSDloadidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
   880  
   881  (MOVBstore [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   882  	(MOVBstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   883  (MOVWstore [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   884  	(MOVWstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   885  (MOVWstore [off1] {sym1} (LEAQ2 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   886  	(MOVWstoreidx2 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   887  (MOVLstore [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   888  	(MOVLstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   889  (MOVLstore [off1] {sym1} (LEAQ4 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   890  	(MOVLstoreidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   891  (MOVQstore [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   892  	(MOVQstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   893  (MOVQstore [off1] {sym1} (LEAQ8 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   894  	(MOVQstoreidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   895  (MOVSSstore [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   896  	(MOVSSstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   897  (MOVSSstore [off1] {sym1} (LEAQ4 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   898  	(MOVSSstoreidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   899  (MOVSDstore [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   900  	(MOVSDstoreidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   901  (MOVSDstore [off1] {sym1} (LEAQ8 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
   902  	(MOVSDstoreidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
   903  
   904  (MOVBload [off] {sym} (ADDQ ptr idx) mem) && ptr.Op != OpSB -> (MOVBloadidx1 [off] {sym} ptr idx mem)
   905  (MOVWload [off] {sym} (ADDQ ptr idx) mem) && ptr.Op != OpSB -> (MOVWloadidx1 [off] {sym} ptr idx mem)
   906  (MOVLload [off] {sym} (ADDQ ptr idx) mem) && ptr.Op != OpSB -> (MOVLloadidx1 [off] {sym} ptr idx mem)
   907  (MOVQload [off] {sym} (ADDQ ptr idx) mem) && ptr.Op != OpSB -> (MOVQloadidx1 [off] {sym} ptr idx mem)
   908  (MOVSSload [off] {sym} (ADDQ ptr idx) mem) && ptr.Op != OpSB -> (MOVSSloadidx1 [off] {sym} ptr idx mem)
   909  (MOVSDload [off] {sym} (ADDQ ptr idx) mem) && ptr.Op != OpSB -> (MOVSDloadidx1 [off] {sym} ptr idx mem)
   910  (MOVBstore [off] {sym} (ADDQ ptr idx) val mem) && ptr.Op != OpSB -> (MOVBstoreidx1 [off] {sym} ptr idx val mem)
   911  (MOVWstore [off] {sym} (ADDQ ptr idx) val mem) && ptr.Op != OpSB -> (MOVWstoreidx1 [off] {sym} ptr idx val mem)
   912  (MOVLstore [off] {sym} (ADDQ ptr idx) val mem) && ptr.Op != OpSB -> (MOVLstoreidx1 [off] {sym} ptr idx val mem)
   913  (MOVQstore [off] {sym} (ADDQ ptr idx) val mem) && ptr.Op != OpSB -> (MOVQstoreidx1 [off] {sym} ptr idx val mem)
   914  (MOVSSstore [off] {sym} (ADDQ ptr idx) val mem) && ptr.Op != OpSB -> (MOVSSstoreidx1 [off] {sym} ptr idx val mem)
   915  (MOVSDstore [off] {sym} (ADDQ ptr idx) val mem) && ptr.Op != OpSB -> (MOVSDstoreidx1 [off] {sym} ptr idx val mem)
   916  
   917  (MOVBstoreconst [x] {sym1} (LEAQ1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
   918  	(MOVBstoreconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
   919  (MOVWstoreconst [x] {sym1} (LEAQ1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
   920  	(MOVWstoreconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
   921  (MOVWstoreconst [x] {sym1} (LEAQ2 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
   922  	(MOVWstoreconstidx2 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
   923  (MOVLstoreconst [x] {sym1} (LEAQ1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
   924  	(MOVLstoreconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
   925  (MOVLstoreconst [x] {sym1} (LEAQ4 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
   926  	(MOVLstoreconstidx4 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
   927  (MOVQstoreconst [x] {sym1} (LEAQ1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
   928  	(MOVQstoreconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
   929  (MOVQstoreconst [x] {sym1} (LEAQ8 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
   930  	(MOVQstoreconstidx8 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
   931  
   932  (MOVBstoreconst [x] {sym} (ADDQ ptr idx) mem) -> (MOVBstoreconstidx1 [x] {sym} ptr idx mem)
   933  (MOVWstoreconst [x] {sym} (ADDQ ptr idx) mem) -> (MOVWstoreconstidx1 [x] {sym} ptr idx mem)
   934  (MOVLstoreconst [x] {sym} (ADDQ ptr idx) mem) -> (MOVLstoreconstidx1 [x] {sym} ptr idx mem)
   935  (MOVQstoreconst [x] {sym} (ADDQ ptr idx) mem) -> (MOVQstoreconstidx1 [x] {sym} ptr idx mem)
   936  
   937  // combine SHLQ into indexed loads and stores
   938  (MOVWloadidx1 [c] {sym} ptr (SHLQconst [1] idx) mem) -> (MOVWloadidx2 [c] {sym} ptr idx mem)
   939  (MOVLloadidx1 [c] {sym} ptr (SHLQconst [2] idx) mem) -> (MOVLloadidx4 [c] {sym} ptr idx mem)
   940  (MOVQloadidx1 [c] {sym} ptr (SHLQconst [3] idx) mem) -> (MOVQloadidx8 [c] {sym} ptr idx mem)
   941  (MOVWstoreidx1 [c] {sym} ptr (SHLQconst [1] idx) val mem) -> (MOVWstoreidx2 [c] {sym} ptr idx val mem)
   942  (MOVLstoreidx1 [c] {sym} ptr (SHLQconst [2] idx) val mem) -> (MOVLstoreidx4 [c] {sym} ptr idx val mem)
   943  (MOVQstoreidx1 [c] {sym} ptr (SHLQconst [3] idx) val mem) -> (MOVQstoreidx8 [c] {sym} ptr idx val mem)
   944  (MOVWstoreconstidx1 [c] {sym} ptr (SHLQconst [1] idx) mem) -> (MOVWstoreconstidx2 [c] {sym} ptr idx mem)
   945  (MOVLstoreconstidx1 [c] {sym} ptr (SHLQconst [2] idx) mem) -> (MOVLstoreconstidx4 [c] {sym} ptr idx mem)
   946  (MOVQstoreconstidx1 [c] {sym} ptr (SHLQconst [3] idx) mem) -> (MOVQstoreconstidx8 [c] {sym} ptr idx mem)
   947  
   948  // combine ADDQ into indexed loads and stores
   949  (MOVBloadidx1 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVBloadidx1 [c+d] {sym} ptr idx mem)
   950  (MOVWloadidx1 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVWloadidx1 [c+d] {sym} ptr idx mem)
   951  (MOVWloadidx2 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVWloadidx2 [c+d] {sym} ptr idx mem)
   952  (MOVLloadidx1 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVLloadidx1 [c+d] {sym} ptr idx mem)
   953  (MOVLloadidx4 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVLloadidx4 [c+d] {sym} ptr idx mem)
   954  (MOVQloadidx1 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVQloadidx1 [c+d] {sym} ptr idx mem)
   955  (MOVQloadidx8 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVQloadidx8 [c+d] {sym} ptr idx mem)
   956  (MOVSSloadidx1 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVSSloadidx1 [c+d] {sym} ptr idx mem)
   957  (MOVSSloadidx4 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVSSloadidx4 [c+d] {sym} ptr idx mem)
   958  (MOVSDloadidx1 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVSDloadidx1 [c+d] {sym} ptr idx mem)
   959  (MOVSDloadidx8 [c] {sym} (ADDQconst [d] ptr) idx mem) -> (MOVSDloadidx8 [c+d] {sym} ptr idx mem)
   960  
   961  (MOVBstoreidx1 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVBstoreidx1 [c+d] {sym} ptr idx val mem)
   962  (MOVWstoreidx1 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVWstoreidx1 [c+d] {sym} ptr idx val mem)
   963  (MOVWstoreidx2 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVWstoreidx2 [c+d] {sym} ptr idx val mem)
   964  (MOVLstoreidx1 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVLstoreidx1 [c+d] {sym} ptr idx val mem)
   965  (MOVLstoreidx4 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVLstoreidx4 [c+d] {sym} ptr idx val mem)
   966  (MOVQstoreidx1 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVQstoreidx1 [c+d] {sym} ptr idx val mem)
   967  (MOVQstoreidx8 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVQstoreidx8 [c+d] {sym} ptr idx val mem)
   968  (MOVSSstoreidx1 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVSSstoreidx1 [c+d] {sym} ptr idx val mem)
   969  (MOVSSstoreidx4 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVSSstoreidx4 [c+d] {sym} ptr idx val mem)
   970  (MOVSDstoreidx1 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVSDstoreidx1 [c+d] {sym} ptr idx val mem)
   971  (MOVSDstoreidx8 [c] {sym} (ADDQconst [d] ptr) idx val mem) -> (MOVSDstoreidx8 [c+d] {sym} ptr idx val mem)
   972  
   973  (MOVBloadidx1 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVBloadidx1 [c+d] {sym} ptr idx mem)
   974  (MOVWloadidx1 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVWloadidx1 [c+d] {sym} ptr idx mem)
   975  (MOVWloadidx2 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVWloadidx2 [c+2*d] {sym} ptr idx mem)
   976  (MOVLloadidx1 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVLloadidx1 [c+d] {sym} ptr idx mem)
   977  (MOVLloadidx4 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVLloadidx4 [c+4*d] {sym} ptr idx mem)
   978  (MOVQloadidx1 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVQloadidx1 [c+d] {sym} ptr idx mem)
   979  (MOVQloadidx8 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVQloadidx8 [c+8*d] {sym} ptr idx mem)
   980  (MOVSSloadidx1 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVSSloadidx1 [c+d] {sym} ptr idx mem)
   981  (MOVSSloadidx4 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVSSloadidx4 [c+4*d] {sym} ptr idx mem)
   982  (MOVSDloadidx1 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVSDloadidx1 [c+d] {sym} ptr idx mem)
   983  (MOVSDloadidx8 [c] {sym} ptr (ADDQconst [d] idx) mem) -> (MOVSDloadidx8 [c+8*d] {sym} ptr idx mem)
   984  
   985  (MOVBstoreidx1 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVBstoreidx1 [c+d] {sym} ptr idx val mem)
   986  (MOVWstoreidx1 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVWstoreidx1 [c+d] {sym} ptr idx val mem)
   987  (MOVWstoreidx2 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVWstoreidx2 [c+2*d] {sym} ptr idx val mem)
   988  (MOVLstoreidx1 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVLstoreidx1 [c+d] {sym} ptr idx val mem)
   989  (MOVLstoreidx4 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVLstoreidx4 [c+4*d] {sym} ptr idx val mem)
   990  (MOVQstoreidx1 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVQstoreidx1 [c+d] {sym} ptr idx val mem)
   991  (MOVQstoreidx8 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVQstoreidx8 [c+8*d] {sym} ptr idx val mem)
   992  (MOVSSstoreidx1 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVSSstoreidx1 [c+d] {sym} ptr idx val mem)
   993  (MOVSSstoreidx4 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVSSstoreidx4 [c+4*d] {sym} ptr idx val mem)
   994  (MOVSDstoreidx1 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVSDstoreidx1 [c+d] {sym} ptr idx val mem)
   995  (MOVSDstoreidx8 [c] {sym} ptr (ADDQconst [d] idx) val mem) -> (MOVSDstoreidx8 [c+8*d] {sym} ptr idx val mem)
   996  
   997  (MOVBstoreconstidx1 [x] {sym} (ADDQconst [c] ptr) idx mem) ->
   998  	(MOVBstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
   999  (MOVWstoreconstidx1 [x] {sym} (ADDQconst [c] ptr) idx mem) ->
  1000  	(MOVWstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1001  (MOVWstoreconstidx2 [x] {sym} (ADDQconst [c] ptr) idx mem) ->
  1002  	(MOVWstoreconstidx2 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1003  (MOVLstoreconstidx1 [x] {sym} (ADDQconst [c] ptr) idx mem) ->
  1004  	(MOVLstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1005  (MOVLstoreconstidx4 [x] {sym} (ADDQconst [c] ptr) idx mem) ->
  1006  	(MOVLstoreconstidx4 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1007  (MOVQstoreconstidx1 [x] {sym} (ADDQconst [c] ptr) idx mem) ->
  1008  	(MOVQstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1009  (MOVQstoreconstidx8 [x] {sym} (ADDQconst [c] ptr) idx mem) ->
  1010  	(MOVQstoreconstidx8 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1011  
  1012  (MOVBstoreconstidx1 [x] {sym} ptr (ADDQconst [c] idx) mem) ->
  1013  	(MOVBstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1014  (MOVWstoreconstidx1 [x] {sym} ptr (ADDQconst [c] idx) mem) ->
  1015  	(MOVWstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1016  (MOVWstoreconstidx2 [x] {sym} ptr (ADDQconst [c] idx) mem) ->
  1017  	(MOVWstoreconstidx2 [ValAndOff(x).add(2*c)] {sym} ptr idx mem)
  1018  (MOVLstoreconstidx1 [x] {sym} ptr (ADDQconst [c] idx) mem) ->
  1019  	(MOVLstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1020  (MOVLstoreconstidx4 [x] {sym} ptr (ADDQconst [c] idx) mem) ->
  1021  	(MOVLstoreconstidx4 [ValAndOff(x).add(4*c)] {sym} ptr idx mem)
  1022  (MOVQstoreconstidx1 [x] {sym} ptr (ADDQconst [c] idx) mem) ->
  1023  	(MOVQstoreconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
  1024  (MOVQstoreconstidx8 [x] {sym} ptr (ADDQconst [c] idx) mem) ->
  1025  	(MOVQstoreconstidx8 [ValAndOff(x).add(8*c)] {sym} ptr idx mem)
  1026  
  1027  // fold LEAQs together
  1028  (LEAQ [off1] {sym1} (LEAQ [off2] {sym2} x)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
  1029        (LEAQ [off1+off2] {mergeSym(sym1,sym2)} x)
  1030  
  1031  // LEAQ into LEAQ1
  1032  (LEAQ1 [off1] {sym1} (LEAQ [off2] {sym2} x) y) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && x.Op != OpSB ->
  1033         (LEAQ1 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1034  (LEAQ1 [off1] {sym1} x (LEAQ [off2] {sym2} y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && y.Op != OpSB ->
  1035         (LEAQ1 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1036  
  1037  // LEAQ1 into LEAQ
  1038  (LEAQ [off1] {sym1} (LEAQ1 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
  1039         (LEAQ1 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1040  
  1041  // LEAQ into LEAQ[248]
  1042  (LEAQ2 [off1] {sym1} (LEAQ [off2] {sym2} x) y) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && x.Op != OpSB ->
  1043         (LEAQ2 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1044  (LEAQ4 [off1] {sym1} (LEAQ [off2] {sym2} x) y) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && x.Op != OpSB ->
  1045         (LEAQ4 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1046  (LEAQ8 [off1] {sym1} (LEAQ [off2] {sym2} x) y) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && x.Op != OpSB ->
  1047         (LEAQ8 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1048  
  1049  // LEAQ[248] into LEAQ
  1050  (LEAQ [off1] {sym1} (LEAQ2 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
  1051        (LEAQ2 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1052  (LEAQ [off1] {sym1} (LEAQ4 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
  1053        (LEAQ4 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1054  (LEAQ [off1] {sym1} (LEAQ8 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
  1055        (LEAQ8 [off1+off2] {mergeSym(sym1,sym2)} x y)
  1056  
  1057  // Absorb InvertFlags into branches.
  1058  (LT (InvertFlags cmp) yes no) -> (GT cmp yes no)
  1059  (GT (InvertFlags cmp) yes no) -> (LT cmp yes no)
  1060  (LE (InvertFlags cmp) yes no) -> (GE cmp yes no)
  1061  (GE (InvertFlags cmp) yes no) -> (LE cmp yes no)
  1062  (ULT (InvertFlags cmp) yes no) -> (UGT cmp yes no)
  1063  (UGT (InvertFlags cmp) yes no) -> (ULT cmp yes no)
  1064  (ULE (InvertFlags cmp) yes no) -> (UGE cmp yes no)
  1065  (UGE (InvertFlags cmp) yes no) -> (ULE cmp yes no)
  1066  (EQ (InvertFlags cmp) yes no) -> (EQ cmp yes no)
  1067  (NE (InvertFlags cmp) yes no) -> (NE cmp yes no)
  1068  
  1069  // Constant comparisons.
  1070  (CMPQconst (MOVQconst [x]) [y]) && x==y -> (FlagEQ)
  1071  (CMPQconst (MOVQconst [x]) [y]) && x<y && uint64(x)<uint64(y) -> (FlagLT_ULT)
  1072  (CMPQconst (MOVQconst [x]) [y]) && x<y && uint64(x)>uint64(y) -> (FlagLT_UGT)
  1073  (CMPQconst (MOVQconst [x]) [y]) && x>y && uint64(x)<uint64(y) -> (FlagGT_ULT)
  1074  (CMPQconst (MOVQconst [x]) [y]) && x>y && uint64(x)>uint64(y) -> (FlagGT_UGT)
  1075  (CMPLconst (MOVLconst [x]) [y]) && int32(x)==int32(y) -> (FlagEQ)
  1076  (CMPLconst (MOVLconst [x]) [y]) && int32(x)<int32(y) && uint32(x)<uint32(y) -> (FlagLT_ULT)
  1077  (CMPLconst (MOVLconst [x]) [y]) && int32(x)<int32(y) && uint32(x)>uint32(y) -> (FlagLT_UGT)
  1078  (CMPLconst (MOVLconst [x]) [y]) && int32(x)>int32(y) && uint32(x)<uint32(y) -> (FlagGT_ULT)
  1079  (CMPLconst (MOVLconst [x]) [y]) && int32(x)>int32(y) && uint32(x)>uint32(y) -> (FlagGT_UGT)
  1080  (CMPWconst (MOVLconst [x]) [y]) && int16(x)==int16(y) -> (FlagEQ)
  1081  (CMPWconst (MOVLconst [x]) [y]) && int16(x)<int16(y) && uint16(x)<uint16(y) -> (FlagLT_ULT)
  1082  (CMPWconst (MOVLconst [x]) [y]) && int16(x)<int16(y) && uint16(x)>uint16(y) -> (FlagLT_UGT)
  1083  (CMPWconst (MOVLconst [x]) [y]) && int16(x)>int16(y) && uint16(x)<uint16(y) -> (FlagGT_ULT)
  1084  (CMPWconst (MOVLconst [x]) [y]) && int16(x)>int16(y) && uint16(x)>uint16(y) -> (FlagGT_UGT)
  1085  (CMPBconst (MOVLconst [x]) [y]) && int8(x)==int8(y) -> (FlagEQ)
  1086  (CMPBconst (MOVLconst [x]) [y]) && int8(x)<int8(y) && uint8(x)<uint8(y) -> (FlagLT_ULT)
  1087  (CMPBconst (MOVLconst [x]) [y]) && int8(x)<int8(y) && uint8(x)>uint8(y) -> (FlagLT_UGT)
  1088  (CMPBconst (MOVLconst [x]) [y]) && int8(x)>int8(y) && uint8(x)<uint8(y) -> (FlagGT_ULT)
  1089  (CMPBconst (MOVLconst [x]) [y]) && int8(x)>int8(y) && uint8(x)>uint8(y) -> (FlagGT_UGT)
  1090  
  1091  // Other known comparisons.
  1092  (CMPQconst (MOVBQZX _) [c]) && 0xFF < c -> (FlagLT_ULT)
  1093  (CMPQconst (MOVWQZX _) [c]) && 0xFFFF < c -> (FlagLT_ULT)
  1094  (CMPQconst (MOVLQZX _) [c]) && 0xFFFFFFFF < c -> (FlagLT_ULT)
  1095  (CMPLconst (SHRLconst _ [c]) [n]) && 0 <= n && 0 < c && c <= 32 && (1<<uint64(32-c)) <= uint64(n) -> (FlagLT_ULT)
  1096  (CMPQconst (SHRQconst _ [c]) [n]) && 0 <= n && 0 < c && c <= 64 && (1<<uint64(64-c)) <= uint64(n) -> (FlagLT_ULT)
  1097  (CMPQconst (ANDQconst _ [m]) [n]) && 0 <= m && m < n -> (FlagLT_ULT)
  1098  (CMPLconst (ANDLconst _ [m]) [n]) && 0 <= int32(m) && int32(m) < int32(n) -> (FlagLT_ULT)
  1099  (CMPWconst (ANDLconst _ [m]) [n]) && 0 <= int16(m) && int16(m) < int16(n) -> (FlagLT_ULT)
  1100  (CMPBconst (ANDLconst _ [m]) [n]) && 0 <= int8(m) && int8(m) < int8(n) -> (FlagLT_ULT)
  1101  // TODO: DIVxU also.
  1102  
  1103  // Absorb flag constants into SBB ops.
  1104  (SBBQcarrymask (FlagEQ)) -> (MOVQconst [0])
  1105  (SBBQcarrymask (FlagLT_ULT)) -> (MOVQconst [-1])
  1106  (SBBQcarrymask (FlagLT_UGT)) -> (MOVQconst [0])
  1107  (SBBQcarrymask (FlagGT_ULT)) -> (MOVQconst [-1])
  1108  (SBBQcarrymask (FlagGT_UGT)) -> (MOVQconst [0])
  1109  (SBBLcarrymask (FlagEQ)) -> (MOVLconst [0])
  1110  (SBBLcarrymask (FlagLT_ULT)) -> (MOVLconst [-1])
  1111  (SBBLcarrymask (FlagLT_UGT)) -> (MOVLconst [0])
  1112  (SBBLcarrymask (FlagGT_ULT)) -> (MOVLconst [-1])
  1113  (SBBLcarrymask (FlagGT_UGT)) -> (MOVLconst [0])
  1114  
  1115  // Absorb flag constants into branches.
  1116  (EQ (FlagEQ) yes no) -> (First nil yes no)
  1117  (EQ (FlagLT_ULT) yes no) -> (First nil no yes)
  1118  (EQ (FlagLT_UGT) yes no) -> (First nil no yes)
  1119  (EQ (FlagGT_ULT) yes no) -> (First nil no yes)
  1120  (EQ (FlagGT_UGT) yes no) -> (First nil no yes)
  1121  
  1122  (NE (FlagEQ) yes no) -> (First nil no yes)
  1123  (NE (FlagLT_ULT) yes no) -> (First nil yes no)
  1124  (NE (FlagLT_UGT) yes no) -> (First nil yes no)
  1125  (NE (FlagGT_ULT) yes no) -> (First nil yes no)
  1126  (NE (FlagGT_UGT) yes no) -> (First nil yes no)
  1127  
  1128  (LT (FlagEQ) yes no) -> (First nil no yes)
  1129  (LT (FlagLT_ULT) yes no) -> (First nil yes no)
  1130  (LT (FlagLT_UGT) yes no) -> (First nil yes no)
  1131  (LT (FlagGT_ULT) yes no) -> (First nil no yes)
  1132  (LT (FlagGT_UGT) yes no) -> (First nil no yes)
  1133  
  1134  (LE (FlagEQ) yes no) -> (First nil yes no)
  1135  (LE (FlagLT_ULT) yes no) -> (First nil yes no)
  1136  (LE (FlagLT_UGT) yes no) -> (First nil yes no)
  1137  (LE (FlagGT_ULT) yes no) -> (First nil no yes)
  1138  (LE (FlagGT_UGT) yes no) -> (First nil no yes)
  1139  
  1140  (GT (FlagEQ) yes no) -> (First nil no yes)
  1141  (GT (FlagLT_ULT) yes no) -> (First nil no yes)
  1142  (GT (FlagLT_UGT) yes no) -> (First nil no yes)
  1143  (GT (FlagGT_ULT) yes no) -> (First nil yes no)
  1144  (GT (FlagGT_UGT) yes no) -> (First nil yes no)
  1145  
  1146  (GE (FlagEQ) yes no) -> (First nil yes no)
  1147  (GE (FlagLT_ULT) yes no) -> (First nil no yes)
  1148  (GE (FlagLT_UGT) yes no) -> (First nil no yes)
  1149  (GE (FlagGT_ULT) yes no) -> (First nil yes no)
  1150  (GE (FlagGT_UGT) yes no) -> (First nil yes no)
  1151  
  1152  (ULT (FlagEQ) yes no) -> (First nil no yes)
  1153  (ULT (FlagLT_ULT) yes no) -> (First nil yes no)
  1154  (ULT (FlagLT_UGT) yes no) -> (First nil no yes)
  1155  (ULT (FlagGT_ULT) yes no) -> (First nil yes no)
  1156  (ULT (FlagGT_UGT) yes no) -> (First nil no yes)
  1157  
  1158  (ULE (FlagEQ) yes no) -> (First nil yes no)
  1159  (ULE (FlagLT_ULT) yes no) -> (First nil yes no)
  1160  (ULE (FlagLT_UGT) yes no) -> (First nil no yes)
  1161  (ULE (FlagGT_ULT) yes no) -> (First nil yes no)
  1162  (ULE (FlagGT_UGT) yes no) -> (First nil no yes)
  1163  
  1164  (UGT (FlagEQ) yes no) -> (First nil no yes)
  1165  (UGT (FlagLT_ULT) yes no) -> (First nil no yes)
  1166  (UGT (FlagLT_UGT) yes no) -> (First nil yes no)
  1167  (UGT (FlagGT_ULT) yes no) -> (First nil no yes)
  1168  (UGT (FlagGT_UGT) yes no) -> (First nil yes no)
  1169  
  1170  (UGE (FlagEQ) yes no) -> (First nil yes no)
  1171  (UGE (FlagLT_ULT) yes no) -> (First nil no yes)
  1172  (UGE (FlagLT_UGT) yes no) -> (First nil yes no)
  1173  (UGE (FlagGT_ULT) yes no) -> (First nil no yes)
  1174  (UGE (FlagGT_UGT) yes no) -> (First nil yes no)
  1175  
  1176  // Absorb flag constants into SETxx ops.
  1177  (SETEQ (FlagEQ)) -> (MOVLconst [1])
  1178  (SETEQ (FlagLT_ULT)) -> (MOVLconst [0])
  1179  (SETEQ (FlagLT_UGT)) -> (MOVLconst [0])
  1180  (SETEQ (FlagGT_ULT)) -> (MOVLconst [0])
  1181  (SETEQ (FlagGT_UGT)) -> (MOVLconst [0])
  1182  
  1183  (SETNE (FlagEQ)) -> (MOVLconst [0])
  1184  (SETNE (FlagLT_ULT)) -> (MOVLconst [1])
  1185  (SETNE (FlagLT_UGT)) -> (MOVLconst [1])
  1186  (SETNE (FlagGT_ULT)) -> (MOVLconst [1])
  1187  (SETNE (FlagGT_UGT)) -> (MOVLconst [1])
  1188  
  1189  (SETL (FlagEQ)) -> (MOVLconst [0])
  1190  (SETL (FlagLT_ULT)) -> (MOVLconst [1])
  1191  (SETL (FlagLT_UGT)) -> (MOVLconst [1])
  1192  (SETL (FlagGT_ULT)) -> (MOVLconst [0])
  1193  (SETL (FlagGT_UGT)) -> (MOVLconst [0])
  1194  
  1195  (SETLE (FlagEQ)) -> (MOVLconst [1])
  1196  (SETLE (FlagLT_ULT)) -> (MOVLconst [1])
  1197  (SETLE (FlagLT_UGT)) -> (MOVLconst [1])
  1198  (SETLE (FlagGT_ULT)) -> (MOVLconst [0])
  1199  (SETLE (FlagGT_UGT)) -> (MOVLconst [0])
  1200  
  1201  (SETG (FlagEQ)) -> (MOVLconst [0])
  1202  (SETG (FlagLT_ULT)) -> (MOVLconst [0])
  1203  (SETG (FlagLT_UGT)) -> (MOVLconst [0])
  1204  (SETG (FlagGT_ULT)) -> (MOVLconst [1])
  1205  (SETG (FlagGT_UGT)) -> (MOVLconst [1])
  1206  
  1207  (SETGE (FlagEQ)) -> (MOVLconst [1])
  1208  (SETGE (FlagLT_ULT)) -> (MOVLconst [0])
  1209  (SETGE (FlagLT_UGT)) -> (MOVLconst [0])
  1210  (SETGE (FlagGT_ULT)) -> (MOVLconst [1])
  1211  (SETGE (FlagGT_UGT)) -> (MOVLconst [1])
  1212  
  1213  (SETB (FlagEQ)) -> (MOVLconst [0])
  1214  (SETB (FlagLT_ULT)) -> (MOVLconst [1])
  1215  (SETB (FlagLT_UGT)) -> (MOVLconst [0])
  1216  (SETB (FlagGT_ULT)) -> (MOVLconst [1])
  1217  (SETB (FlagGT_UGT)) -> (MOVLconst [0])
  1218  
  1219  (SETBE (FlagEQ)) -> (MOVLconst [1])
  1220  (SETBE (FlagLT_ULT)) -> (MOVLconst [1])
  1221  (SETBE (FlagLT_UGT)) -> (MOVLconst [0])
  1222  (SETBE (FlagGT_ULT)) -> (MOVLconst [1])
  1223  (SETBE (FlagGT_UGT)) -> (MOVLconst [0])
  1224  
  1225  (SETA (FlagEQ)) -> (MOVLconst [0])
  1226  (SETA (FlagLT_ULT)) -> (MOVLconst [0])
  1227  (SETA (FlagLT_UGT)) -> (MOVLconst [1])
  1228  (SETA (FlagGT_ULT)) -> (MOVLconst [0])
  1229  (SETA (FlagGT_UGT)) -> (MOVLconst [1])
  1230  
  1231  (SETAE (FlagEQ)) -> (MOVLconst [1])
  1232  (SETAE (FlagLT_ULT)) -> (MOVLconst [0])
  1233  (SETAE (FlagLT_UGT)) -> (MOVLconst [1])
  1234  (SETAE (FlagGT_ULT)) -> (MOVLconst [0])
  1235  (SETAE (FlagGT_UGT)) -> (MOVLconst [1])
  1236  
  1237  // Remove redundant *const ops
  1238  (ADDQconst [0] x) -> x
  1239  (ADDLconst [c] x) && int32(c)==0 -> x
  1240  (SUBQconst [0] x) -> x
  1241  (SUBLconst [c] x) && int32(c) == 0 -> x
  1242  (ANDQconst [0] _)                 -> (MOVQconst [0])
  1243  (ANDLconst [c] _) && int32(c)==0  -> (MOVLconst [0])
  1244  (ANDQconst [-1] x)                -> x
  1245  (ANDLconst [c] x) && int32(c)==-1 -> x
  1246  (ORQconst [0] x)                  -> x
  1247  (ORLconst [c] x) && int32(c)==0   -> x
  1248  (ORQconst [-1] _)                 -> (MOVQconst [-1])
  1249  (ORLconst [c] _) && int32(c)==-1  -> (MOVLconst [-1])
  1250  (XORQconst [0] x)                  -> x
  1251  (XORLconst [c] x) && int32(c)==0   -> x
  1252  // TODO: since we got rid of the W/B versions, we might miss
  1253  // things like (ANDLconst [0x100] x) which were formerly
  1254  // (ANDBconst [0] x).  Probably doesn't happen very often.
  1255  // If we cared, we might do:
  1256  //  (ANDLconst <t> [c] x) && t.Size()==1 && int8(x)==0 -> (MOVLconst [0])
  1257  
  1258  // Convert constant subtracts to constant adds
  1259  (SUBQconst [c] x) && c != -(1<<31) -> (ADDQconst [-c] x)
  1260  (SUBLconst [c] x) -> (ADDLconst [int64(int32(-c))] x)
  1261  
  1262  // generic constant folding
  1263  // TODO: more of this
  1264  (ADDQconst [c] (MOVQconst [d])) -> (MOVQconst [c+d])
  1265  (ADDLconst [c] (MOVLconst [d])) -> (MOVLconst [int64(int32(c+d))])
  1266  (ADDQconst [c] (ADDQconst [d] x)) && is32Bit(c+d) -> (ADDQconst [c+d] x)
  1267  (ADDLconst [c] (ADDLconst [d] x)) -> (ADDLconst [int64(int32(c+d))] x)
  1268  (SUBQconst (MOVQconst [d]) [c]) -> (MOVQconst [d-c])
  1269  (SUBQconst (SUBQconst x [d]) [c]) && is32Bit(-c-d) -> (ADDQconst [-c-d] x)
  1270  (SARQconst [c] (MOVQconst [d])) -> (MOVQconst [d>>uint64(c)])
  1271  (SARLconst [c] (MOVQconst [d])) -> (MOVQconst [d>>uint64(c)])
  1272  (SARWconst [c] (MOVQconst [d])) -> (MOVQconst [d>>uint64(c)])
  1273  (SARBconst [c] (MOVQconst [d])) -> (MOVQconst [d>>uint64(c)])
  1274  (NEGQ (MOVQconst [c])) -> (MOVQconst [-c])
  1275  (NEGL (MOVLconst [c])) -> (MOVLconst [int64(int32(-c))])
  1276  (MULQconst [c] (MOVQconst [d])) -> (MOVQconst [c*d])
  1277  (MULLconst [c] (MOVLconst [d])) -> (MOVLconst [int64(int32(c*d))])
  1278  (ANDQconst [c] (MOVQconst [d])) -> (MOVQconst [c&d])
  1279  (ANDLconst [c] (MOVLconst [d])) -> (MOVLconst [c&d])
  1280  (ORQconst [c] (MOVQconst [d])) -> (MOVQconst [c|d])
  1281  (ORLconst [c] (MOVLconst [d])) -> (MOVLconst [c|d])
  1282  (XORQconst [c] (MOVQconst [d])) -> (MOVQconst [c^d])
  1283  (XORLconst [c] (MOVLconst [d])) -> (MOVLconst [c^d])
  1284  (NOTQ (MOVQconst [c])) -> (MOVQconst [^c])
  1285  (NOTL (MOVLconst [c])) -> (MOVLconst [^c])
  1286  
  1287  // generic simplifications
  1288  // TODO: more of this
  1289  (ADDQ x (NEGQ y)) -> (SUBQ x y)
  1290  (ADDL x (NEGL y)) -> (SUBL x y)
  1291  (SUBQ x x) -> (MOVQconst [0])
  1292  (SUBL x x) -> (MOVLconst [0])
  1293  (ANDQ x x) -> x
  1294  (ANDL x x) -> x
  1295  (ORQ x x) -> x
  1296  (ORL x x) -> x
  1297  (XORQ x x) -> (MOVQconst [0])
  1298  (XORL x x) -> (MOVLconst [0])
  1299  
  1300  // checking AND against 0.
  1301  (CMPQconst (ANDQ x y) [0]) -> (TESTQ x y)
  1302  (CMPLconst (ANDL x y) [0]) -> (TESTL x y)
  1303  (CMPWconst (ANDL x y) [0]) -> (TESTW x y)
  1304  (CMPBconst (ANDL x y) [0]) -> (TESTB x y)
  1305  (CMPQconst (ANDQconst [c] x) [0]) -> (TESTQconst [c] x)
  1306  (CMPLconst (ANDLconst [c] x) [0]) -> (TESTLconst [c] x)
  1307  (CMPWconst (ANDLconst [c] x) [0]) -> (TESTWconst [int64(int16(c))] x)
  1308  (CMPBconst (ANDLconst [c] x) [0]) -> (TESTBconst [int64(int8(c))] x)
  1309  
  1310  // TEST %reg,%reg is shorter than CMP
  1311  (CMPQconst x [0]) -> (TESTQ x x)
  1312  (CMPLconst x [0]) -> (TESTL x x)
  1313  (CMPWconst x [0]) -> (TESTW x x)
  1314  (CMPBconst x [0]) -> (TESTB x x)
  1315  
  1316  // Combining byte loads into larger (unaligned) loads.
  1317  // There are many ways these combinations could occur.  This is
  1318  // designed to match the way encoding/binary.LittleEndian does it.
  1319  (ORL                  x0:(MOVBload [i]   {s} p mem)
  1320      s0:(SHLLconst [8] x1:(MOVBload [i+1] {s} p mem)))
  1321    && x0.Uses == 1
  1322    && x1.Uses == 1
  1323    && s0.Uses == 1
  1324    && mergePoint(b,x0,x1) != nil
  1325    && clobber(x0)
  1326    && clobber(x1)
  1327    && clobber(s0)
  1328    -> @mergePoint(b,x0,x1) (MOVWload [i] {s} p mem)
  1329  
  1330  (ORL o0:(ORL o1:(ORL
  1331                         x0:(MOVBload [i]   {s} p mem)
  1332      s0:(SHLLconst [8]  x1:(MOVBload [i+1] {s} p mem)))
  1333      s1:(SHLLconst [16] x2:(MOVBload [i+2] {s} p mem)))
  1334      s2:(SHLLconst [24] x3:(MOVBload [i+3] {s} p mem)))
  1335    && x0.Uses == 1
  1336    && x1.Uses == 1
  1337    && x2.Uses == 1
  1338    && x3.Uses == 1
  1339    && s0.Uses == 1
  1340    && s1.Uses == 1
  1341    && s2.Uses == 1
  1342    && o0.Uses == 1
  1343    && o1.Uses == 1
  1344    && mergePoint(b,x0,x1,x2,x3) != nil
  1345    && clobber(x0)
  1346    && clobber(x1)
  1347    && clobber(x2)
  1348    && clobber(x3)
  1349    && clobber(s0)
  1350    && clobber(s1)
  1351    && clobber(s2)
  1352    && clobber(o0)
  1353    && clobber(o1)
  1354    -> @mergePoint(b,x0,x1,x2,x3) (MOVLload [i] {s} p mem)
  1355  
  1356  (ORQ o0:(ORQ o1:(ORQ o2:(ORQ o3:(ORQ o4:(ORQ o5:(ORQ
  1357                         x0:(MOVBload [i]   {s} p mem)
  1358      s0:(SHLQconst [8]  x1:(MOVBload [i+1] {s} p mem)))
  1359      s1:(SHLQconst [16] x2:(MOVBload [i+2] {s} p mem)))
  1360      s2:(SHLQconst [24] x3:(MOVBload [i+3] {s} p mem)))
  1361      s3:(SHLQconst [32] x4:(MOVBload [i+4] {s} p mem)))
  1362      s4:(SHLQconst [40] x5:(MOVBload [i+5] {s} p mem)))
  1363      s5:(SHLQconst [48] x6:(MOVBload [i+6] {s} p mem)))
  1364      s6:(SHLQconst [56] x7:(MOVBload [i+7] {s} p mem)))
  1365    && x0.Uses == 1
  1366    && x1.Uses == 1
  1367    && x2.Uses == 1
  1368    && x3.Uses == 1
  1369    && x4.Uses == 1
  1370    && x5.Uses == 1
  1371    && x6.Uses == 1
  1372    && x7.Uses == 1
  1373    && s0.Uses == 1
  1374    && s1.Uses == 1
  1375    && s2.Uses == 1
  1376    && s3.Uses == 1
  1377    && s4.Uses == 1
  1378    && s5.Uses == 1
  1379    && s6.Uses == 1
  1380    && o0.Uses == 1
  1381    && o1.Uses == 1
  1382    && o2.Uses == 1
  1383    && o3.Uses == 1
  1384    && o4.Uses == 1
  1385    && o5.Uses == 1
  1386    && mergePoint(b,x0,x1,x2,x3,x4,x5,x6,x7) != nil
  1387    && clobber(x0)
  1388    && clobber(x1)
  1389    && clobber(x2)
  1390    && clobber(x3)
  1391    && clobber(x4)
  1392    && clobber(x5)
  1393    && clobber(x6)
  1394    && clobber(x7)
  1395    && clobber(s0)
  1396    && clobber(s1)
  1397    && clobber(s2)
  1398    && clobber(s3)
  1399    && clobber(s4)
  1400    && clobber(s5)
  1401    && clobber(s6)
  1402    && clobber(o0)
  1403    && clobber(o1)
  1404    && clobber(o2)
  1405    && clobber(o3)
  1406    && clobber(o4)
  1407    && clobber(o5)
  1408    -> @mergePoint(b,x0,x1,x2,x3,x4,x5,x6,x7) (MOVQload [i] {s} p mem)
  1409  
  1410  (ORL                  x0:(MOVBloadidx1 [i]   {s} p idx mem)
  1411      s0:(SHLLconst [8] x1:(MOVBloadidx1 [i+1] {s} p idx mem)))
  1412    && x0.Uses == 1
  1413    && x1.Uses == 1
  1414    && s0.Uses == 1
  1415    && mergePoint(b,x0,x1) != nil
  1416    && clobber(x0)
  1417    && clobber(x1)
  1418    && clobber(s0)
  1419    -> @mergePoint(b,x0,x1) (MOVWloadidx1 <v.Type> [i] {s} p idx mem)
  1420  
  1421  (ORL o0:(ORL o1:(ORL
  1422                         x0:(MOVBloadidx1 [i]   {s} p idx mem)
  1423      s0:(SHLLconst [8]  x1:(MOVBloadidx1 [i+1] {s} p idx mem)))
  1424      s1:(SHLLconst [16] x2:(MOVBloadidx1 [i+2] {s} p idx mem)))
  1425      s2:(SHLLconst [24] x3:(MOVBloadidx1 [i+3] {s} p idx mem)))
  1426    && x0.Uses == 1
  1427    && x1.Uses == 1
  1428    && x2.Uses == 1
  1429    && x3.Uses == 1
  1430    && s0.Uses == 1
  1431    && s1.Uses == 1
  1432    && s2.Uses == 1
  1433    && o0.Uses == 1
  1434    && o1.Uses == 1
  1435    && mergePoint(b,x0,x1,x2,x3) != nil
  1436    && clobber(x0)
  1437    && clobber(x1)
  1438    && clobber(x2)
  1439    && clobber(x3)
  1440    && clobber(s0)
  1441    && clobber(s1)
  1442    && clobber(s2)
  1443    && clobber(o0)
  1444    && clobber(o1)
  1445    -> @mergePoint(b,x0,x1,x2,x3) (MOVLloadidx1 <v.Type> [i] {s} p idx mem)
  1446  
  1447  (ORQ o0:(ORQ o1:(ORQ o2:(ORQ o3:(ORQ o4:(ORQ o5:(ORQ
  1448                         x0:(MOVBloadidx1 [i]   {s} p idx mem)
  1449      s0:(SHLQconst [8]  x1:(MOVBloadidx1 [i+1] {s} p idx mem)))
  1450      s1:(SHLQconst [16] x2:(MOVBloadidx1 [i+2] {s} p idx mem)))
  1451      s2:(SHLQconst [24] x3:(MOVBloadidx1 [i+3] {s} p idx mem)))
  1452      s3:(SHLQconst [32] x4:(MOVBloadidx1 [i+4] {s} p idx mem)))
  1453      s4:(SHLQconst [40] x5:(MOVBloadidx1 [i+5] {s} p idx mem)))
  1454      s5:(SHLQconst [48] x6:(MOVBloadidx1 [i+6] {s} p idx mem)))
  1455      s6:(SHLQconst [56] x7:(MOVBloadidx1 [i+7] {s} p idx mem)))
  1456    && x0.Uses == 1
  1457    && x1.Uses == 1
  1458    && x2.Uses == 1
  1459    && x3.Uses == 1
  1460    && x4.Uses == 1
  1461    && x5.Uses == 1
  1462    && x6.Uses == 1
  1463    && x7.Uses == 1
  1464    && s0.Uses == 1
  1465    && s1.Uses == 1
  1466    && s2.Uses == 1
  1467    && s3.Uses == 1
  1468    && s4.Uses == 1
  1469    && s5.Uses == 1
  1470    && s6.Uses == 1
  1471    && o0.Uses == 1
  1472    && o1.Uses == 1
  1473    && o2.Uses == 1
  1474    && o3.Uses == 1
  1475    && o4.Uses == 1
  1476    && o5.Uses == 1
  1477    && mergePoint(b,x0,x1,x2,x3,x4,x5,x6,x7) != nil
  1478    && clobber(x0)
  1479    && clobber(x1)
  1480    && clobber(x2)
  1481    && clobber(x3)
  1482    && clobber(x4)
  1483    && clobber(x5)
  1484    && clobber(x6)
  1485    && clobber(x7)
  1486    && clobber(s0)
  1487    && clobber(s1)
  1488    && clobber(s2)
  1489    && clobber(s3)
  1490    && clobber(s4)
  1491    && clobber(s5)
  1492    && clobber(s6)
  1493    && clobber(o0)
  1494    && clobber(o1)
  1495    && clobber(o2)
  1496    && clobber(o3)
  1497    && clobber(o4)
  1498    && clobber(o5)
  1499    -> @mergePoint(b,x0,x1,x2,x3,x4,x5,x6,x7) (MOVQloadidx1 <v.Type> [i] {s} p idx mem)
  1500  
  1501  // Combine constant stores into larger (unaligned) stores.
  1502  (MOVBstoreconst [c] {s} p x:(MOVBstoreconst [a] {s} p mem))
  1503    && x.Uses == 1
  1504    && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
  1505    && clobber(x)
  1506    -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p mem)
  1507  (MOVWstoreconst [c] {s} p x:(MOVWstoreconst [a] {s} p mem))
  1508    && x.Uses == 1
  1509    && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
  1510    && clobber(x)
  1511    -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p mem)
  1512  (MOVLstoreconst [c] {s} p x:(MOVLstoreconst [a] {s} p mem))
  1513    && x.Uses == 1
  1514    && ValAndOff(a).Off() + 4 == ValAndOff(c).Off()
  1515    && clobber(x)
  1516    -> (MOVQstore [ValAndOff(a).Off()] {s} p (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
  1517  
  1518  (MOVBstoreconstidx1 [c] {s} p i x:(MOVBstoreconstidx1 [a] {s} p i mem))
  1519    && x.Uses == 1
  1520    && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
  1521    && clobber(x)
  1522    -> (MOVWstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p i mem)
  1523  (MOVWstoreconstidx1 [c] {s} p i x:(MOVWstoreconstidx1 [a] {s} p i mem))
  1524    && x.Uses == 1
  1525    && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
  1526    && clobber(x)
  1527    -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p i mem)
  1528  (MOVLstoreconstidx1 [c] {s} p i x:(MOVLstoreconstidx1 [a] {s} p i mem))
  1529    && x.Uses == 1
  1530    && ValAndOff(a).Off() + 4 == ValAndOff(c).Off()
  1531    && clobber(x)
  1532    -> (MOVQstoreidx1 [ValAndOff(a).Off()] {s} p i (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
  1533  
  1534  (MOVWstoreconstidx2 [c] {s} p i x:(MOVWstoreconstidx2 [a] {s} p i mem))
  1535    && x.Uses == 1
  1536    && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
  1537    && clobber(x)
  1538    -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p (SHLQconst <i.Type> [1] i) mem)
  1539  (MOVLstoreconstidx4 [c] {s} p i x:(MOVLstoreconstidx4 [a] {s} p i mem))
  1540    && x.Uses == 1
  1541    && ValAndOff(a).Off() + 4 == ValAndOff(c).Off()
  1542    && clobber(x)
  1543    -> (MOVQstoreidx1 [ValAndOff(a).Off()] {s} p (SHLQconst <i.Type> [2] i) (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
  1544  
  1545  // Combine stores into larger (unaligned) stores.
  1546  (MOVBstore [i] {s} p (SHRQconst [8] w) x:(MOVBstore [i-1] {s} p w mem))
  1547    && x.Uses == 1
  1548    && clobber(x)
  1549    -> (MOVWstore [i-1] {s} p w mem)
  1550  (MOVBstore [i] {s} p (SHRQconst [j] w) x:(MOVBstore [i-1] {s} p w0:(SHRQconst [j-8] w) mem))
  1551    && x.Uses == 1
  1552    && clobber(x)
  1553    -> (MOVWstore [i-1] {s} p w0 mem)
  1554  (MOVWstore [i] {s} p (SHRQconst [16] w) x:(MOVWstore [i-2] {s} p w mem))
  1555    && x.Uses == 1
  1556    && clobber(x)
  1557    -> (MOVLstore [i-2] {s} p w mem)
  1558  (MOVWstore [i] {s} p (SHRQconst [j] w) x:(MOVWstore [i-2] {s} p w0:(SHRQconst [j-16] w) mem))
  1559    && x.Uses == 1
  1560    && clobber(x)
  1561    -> (MOVLstore [i-2] {s} p w0 mem)
  1562  (MOVLstore [i] {s} p (SHRQconst [32] w) x:(MOVLstore [i-4] {s} p w mem))
  1563    && x.Uses == 1
  1564    && clobber(x)
  1565    -> (MOVQstore [i-4] {s} p w mem)
  1566  (MOVLstore [i] {s} p (SHRQconst [j] w) x:(MOVLstore [i-4] {s} p w0:(SHRQconst [j-32] w) mem))
  1567    && x.Uses == 1
  1568    && clobber(x)
  1569    -> (MOVQstore [i-4] {s} p w0 mem)
  1570  
  1571  (MOVBstoreidx1 [i] {s} p idx (SHRQconst [8] w) x:(MOVBstoreidx1 [i-1] {s} p idx w mem))
  1572    && x.Uses == 1
  1573    && clobber(x)
  1574    -> (MOVWstoreidx1 [i-1] {s} p idx w mem)
  1575  (MOVBstoreidx1 [i] {s} p idx (SHRQconst [j] w) x:(MOVBstoreidx1 [i-1] {s} p idx w0:(SHRQconst [j-8] w) mem))
  1576    && x.Uses == 1
  1577    && clobber(x)
  1578    -> (MOVWstoreidx1 [i-1] {s} p idx w0 mem)
  1579  (MOVWstoreidx1 [i] {s} p idx (SHRQconst [16] w) x:(MOVWstoreidx1 [i-2] {s} p idx w mem))
  1580    && x.Uses == 1
  1581    && clobber(x)
  1582    -> (MOVLstoreidx1 [i-2] {s} p idx w mem)
  1583  (MOVWstoreidx1 [i] {s} p idx (SHRQconst [j] w) x:(MOVWstoreidx1 [i-2] {s} p idx w0:(SHRQconst [j-16] w) mem))
  1584    && x.Uses == 1
  1585    && clobber(x)
  1586    -> (MOVLstoreidx1 [i-2] {s} p idx w0 mem)
  1587  (MOVLstoreidx1 [i] {s} p idx (SHRQconst [32] w) x:(MOVLstoreidx1 [i-4] {s} p idx w mem))
  1588    && x.Uses == 1
  1589    && clobber(x)
  1590    -> (MOVQstoreidx1 [i-4] {s} p idx w mem)
  1591  (MOVLstoreidx1 [i] {s} p idx (SHRQconst [j] w) x:(MOVLstoreidx1 [i-4] {s} p idx w0:(SHRQconst [j-32] w) mem))
  1592    && x.Uses == 1
  1593    && clobber(x)
  1594    -> (MOVQstoreidx1 [i-4] {s} p idx w0 mem)
  1595  
  1596  (MOVWstoreidx2 [i] {s} p idx (SHRQconst [16] w) x:(MOVWstoreidx2 [i-2] {s} p idx w mem))
  1597    && x.Uses == 1
  1598    && clobber(x)
  1599    -> (MOVLstoreidx1 [i-2] {s} p (SHLQconst <idx.Type> [1] idx) w mem)
  1600  (MOVWstoreidx2 [i] {s} p idx (SHRQconst [j] w) x:(MOVWstoreidx2 [i-2] {s} p idx w0:(SHRQconst [j-16] w) mem))
  1601    && x.Uses == 1
  1602    && clobber(x)
  1603    -> (MOVLstoreidx1 [i-2] {s} p (SHLQconst <idx.Type> [1] idx) w0 mem)
  1604  (MOVLstoreidx4 [i] {s} p idx (SHRQconst [32] w) x:(MOVLstoreidx4 [i-4] {s} p idx w mem))
  1605    && x.Uses == 1
  1606    && clobber(x)
  1607    -> (MOVQstoreidx1 [i-4] {s} p (SHLQconst <idx.Type> [2] idx) w mem)
  1608  (MOVLstoreidx4 [i] {s} p idx (SHRQconst [j] w) x:(MOVLstoreidx4 [i-4] {s} p idx w0:(SHRQconst [j-32] w) mem))
  1609    && x.Uses == 1
  1610    && clobber(x)
  1611    -> (MOVQstoreidx1 [i-4] {s} p (SHLQconst <idx.Type> [2] idx) w0 mem)
  1612  
  1613  // amd64p32 rules
  1614  // same as the rules above, but with 32 instead of 64 bit pointer arithmetic.
  1615  // LEAQ,ADDQ -> LEAL,ADDL
  1616  (ADDLconst [c] (LEAL [d] {s} x)) && is32Bit(c+d) -> (LEAL [c+d] {s} x)
  1617  (LEAL [c] {s} (ADDLconst [d] x)) && is32Bit(c+d) -> (LEAL [c+d] {s} x)
  1618  
  1619  (MOVQload  [off1] {sym1} (LEAL [off2] {sym2} base) mem) && canMergeSym(sym1, sym2) ->
  1620  	(MOVQload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
  1621  (MOVLload  [off1] {sym1} (LEAL [off2] {sym2} base) mem) && canMergeSym(sym1, sym2) ->
  1622  	(MOVLload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
  1623  (MOVWload  [off1] {sym1} (LEAL [off2] {sym2} base) mem) && canMergeSym(sym1, sym2) ->
  1624  	(MOVWload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
  1625  (MOVBload  [off1] {sym1} (LEAL [off2] {sym2} base) mem) && canMergeSym(sym1, sym2) ->
  1626  	(MOVBload  [off1+off2] {mergeSym(sym1,sym2)} base mem)
  1627  
  1628  (MOVQstore  [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && canMergeSym(sym1, sym2) ->
  1629  	(MOVQstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
  1630  (MOVLstore  [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && canMergeSym(sym1, sym2) ->
  1631  	(MOVLstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
  1632  (MOVWstore  [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && canMergeSym(sym1, sym2) ->
  1633  	(MOVWstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
  1634  (MOVBstore  [off1] {sym1} (LEAL [off2] {sym2} base) val mem) && canMergeSym(sym1, sym2) ->
  1635  	(MOVBstore  [off1+off2] {mergeSym(sym1,sym2)} base val mem)
  1636  
  1637  (MOVQstoreconst [sc] {sym1} (LEAL [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off) ->
  1638  	(MOVQstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
  1639  (MOVLstoreconst [sc] {sym1} (LEAL [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off) ->
  1640  	(MOVLstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
  1641  (MOVWstoreconst [sc] {sym1} (LEAL [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off) ->
  1642  	(MOVWstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
  1643  (MOVBstoreconst [sc] {sym1} (LEAL [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd(off) ->
  1644  	(MOVBstoreconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
  1645  
  1646  (MOVQload  [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVQload  [off1+off2] {sym} ptr mem)
  1647  (MOVLload  [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVLload  [off1+off2] {sym} ptr mem)
  1648  (MOVWload  [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVWload  [off1+off2] {sym} ptr mem)
  1649  (MOVBload  [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOVBload  [off1+off2] {sym} ptr mem)
  1650  (MOVQstore  [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVQstore  [off1+off2] {sym} ptr val mem)
  1651  (MOVLstore  [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVLstore  [off1+off2] {sym} ptr val mem)
  1652  (MOVWstore  [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVWstore  [off1+off2] {sym} ptr val mem)
  1653  (MOVBstore  [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOVBstore  [off1+off2] {sym} ptr val mem)
  1654  (MOVQstoreconst [sc] {s} (ADDLconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
  1655  	(MOVQstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
  1656  (MOVLstoreconst [sc] {s} (ADDLconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
  1657  	(MOVLstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
  1658  (MOVWstoreconst [sc] {s} (ADDLconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
  1659  	(MOVWstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
  1660  (MOVBstoreconst [sc] {s} (ADDLconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
  1661  	(MOVBstoreconst [ValAndOff(sc).add(off)] {s} ptr mem)
  1662  
  1663  // Merge ADDQconst and LEAQ into atomic loads.
  1664  (MOVQatomicload [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) ->
  1665  	(MOVQatomicload [off1+off2] {sym} ptr mem)
  1666  (MOVLatomicload [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) ->
  1667  	(MOVLatomicload [off1+off2] {sym} ptr mem)
  1668  (MOVQatomicload [off1] {sym1} (LEAQ [off2] {sym2} ptr) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
  1669  	(MOVQatomicload [off1+off2] {mergeSym(sym1,sym2)} ptr mem)
  1670  (MOVLatomicload [off1] {sym1} (LEAQ [off2] {sym2} ptr) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
  1671  	(MOVLatomicload [off1+off2] {mergeSym(sym1,sym2)} ptr mem)
  1672  
  1673  // Merge ADDQconst and LEAQ into atomic stores.
  1674  (XCHGQ [off1] {sym} val (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) ->
  1675  	(XCHGQ [off1+off2] {sym} val ptr mem)
  1676  (XCHGQ [off1] {sym1} val (LEAQ [off2] {sym2} ptr) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && ptr.Op != OpSB ->
  1677  	(XCHGQ [off1+off2] {mergeSym(sym1,sym2)} val ptr mem)
  1678  (XCHGL [off1] {sym} val (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) ->
  1679  	(XCHGL [off1+off2] {sym} val ptr mem)
  1680  (XCHGL [off1] {sym1} val (LEAQ [off2] {sym2} ptr) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) && ptr.Op != OpSB ->
  1681  	(XCHGL [off1+off2] {mergeSym(sym1,sym2)} val ptr mem)
  1682  
  1683  // Merge ADDQconst into atomic adds.
  1684  // TODO: merging LEAQ doesn't work, assembler doesn't like the resulting instructions.
  1685  (XADDQlock [off1] {sym} val (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) ->
  1686  	(XADDQlock [off1+off2] {sym} val ptr mem)
  1687  (XADDLlock [off1] {sym} val (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) ->
  1688  	(XADDLlock [off1+off2] {sym} val ptr mem)
  1689  
  1690  // Merge ADDQconst into atomic compare and swaps.
  1691  // TODO: merging LEAQ doesn't work, assembler doesn't like the resulting instructions.
  1692  (CMPXCHGQlock [off1] {sym} (ADDQconst [off2] ptr) old new_ mem) && is32Bit(off1+off2) ->
  1693  	(CMPXCHGQlock [off1+off2] {sym} ptr old new_ mem)
  1694  (CMPXCHGLlock [off1] {sym} (ADDQconst [off2] ptr) old new_ mem) && is32Bit(off1+off2) ->
  1695  	(CMPXCHGLlock [off1+off2] {sym} ptr old new_ mem)