github.com/gocuntian/go@v0.0.0-20160610041250-fee02d270bf8/src/cmd/compile/internal/ssa/gen/generic.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 // values are specified using the following format: 6 // (op <type> [auxint] {aux} arg0 arg1 ...) 7 // the type, aux, and auxint fields are optional 8 // on the matching side 9 // - the type, aux, and auxint fields must match if they are specified. 10 // - the first occurrence of a variable defines that variable. Subsequent 11 // uses must match (be == to) the first use. 12 // - v is defined to be the value matched. 13 // - an additional conditional can be provided after the match pattern with "&&". 14 // on the generated side 15 // - the type of the top-level expression is the same as the one on the left-hand side. 16 // - the type of any subexpressions must be specified explicitly (or 17 // be specified in the op's type field). 18 // - auxint will be 0 if not specified. 19 // - aux will be nil if not specified. 20 21 // blocks are specified using the following format: 22 // (kind controlvalue succ0 succ1 ...) 23 // controlvalue must be "nil" or a value expression 24 // succ* fields must be variables 25 // For now, the generated successors must be a permutation of the matched successors. 26 27 // constant folding 28 (Trunc16to8 (Const16 [c])) -> (Const8 [int64(int8(c))]) 29 (Trunc32to8 (Const32 [c])) -> (Const8 [int64(int8(c))]) 30 (Trunc32to16 (Const32 [c])) -> (Const16 [int64(int16(c))]) 31 (Trunc64to8 (Const64 [c])) -> (Const8 [int64(int8(c))]) 32 (Trunc64to16 (Const64 [c])) -> (Const16 [int64(int16(c))]) 33 (Trunc64to32 (Const64 [c])) -> (Const32 [int64(int32(c))]) 34 (Cvt64Fto32F (Const64F [c])) -> (Const32F [f2i(float64(i2f32(c)))]) 35 (Cvt32Fto64F (Const32F [c])) -> (Const64F [c]) // c is already a 64 bit float 36 37 // const negation is currently handled by frontend 38 //(Neg8 (Const8 [c])) -> (Const8 [-c]) 39 //(Neg16 (Const16 [c])) -> (Const16 [-c]) 40 //(Neg32 (Const32 [c])) -> (Const32 [-c]) 41 //(Neg64 (Const64 [c])) -> (Const64 [-c]) 42 //(Neg32F (Const32F [c])) -> (Const32F [f2i(-i2f(c))]) 43 //(Neg64F (Const64F [c])) -> (Const64F [f2i(-i2f(c))]) 44 45 (Add8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c+d))]) 46 (Add16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c+d))]) 47 (Add32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c+d))]) 48 (Add64 (Const64 [c]) (Const64 [d])) -> (Const64 [c+d]) 49 (Add32F (Const32F [c]) (Const32F [d])) -> 50 (Const32F [f2i(float64(i2f32(c) + i2f32(d)))]) // ensure we combine the operands with 32 bit precision 51 (Add64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) + i2f(d))]) 52 (AddPtr <t> x (Const64 [c])) -> (OffPtr <t> x [c]) 53 54 (Sub8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c-d))]) 55 (Sub16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c-d))]) 56 (Sub32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c-d))]) 57 (Sub64 (Const64 [c]) (Const64 [d])) -> (Const64 [c-d]) 58 (Sub32F (Const32F [c]) (Const32F [d])) -> 59 (Const32F [f2i(float64(i2f32(c) - i2f32(d)))]) 60 (Sub64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) - i2f(d))]) 61 62 (Mul8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c*d))]) 63 (Mul16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c*d))]) 64 (Mul32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c*d))]) 65 (Mul64 (Const64 [c]) (Const64 [d])) -> (Const64 [c*d]) 66 (Mul32F (Const32F [c]) (Const32F [d])) -> 67 (Const32F [f2i(float64(i2f32(c) * i2f32(d)))]) 68 (Mul64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) * i2f(d))]) 69 70 (Mod8 (Const8 [c]) (Const8 [d])) && d != 0 -> (Const8 [int64(int8(c % d))]) 71 (Mod16 (Const16 [c]) (Const16 [d])) && d != 0 -> (Const16 [int64(int16(c % d))]) 72 (Mod32 (Const32 [c]) (Const32 [d])) && d != 0 -> (Const32 [int64(int32(c % d))]) 73 (Mod64 (Const64 [c]) (Const64 [d])) && d != 0 -> (Const64 [c % d]) 74 75 (Mod8u (Const8 [c]) (Const8 [d])) && d != 0 -> (Const8 [int64(uint8(c) % uint8(d))]) 76 (Mod16u (Const16 [c]) (Const16 [d])) && d != 0 -> (Const16 [int64(uint16(c) % uint16(d))]) 77 (Mod32u (Const32 [c]) (Const32 [d])) && d != 0 -> (Const32 [int64(uint32(c) % uint32(d))]) 78 (Mod64u (Const64 [c]) (Const64 [d])) && d != 0 -> (Const64 [int64(uint64(c) % uint64(d))]) 79 80 (Lsh64x64 (Const64 [c]) (Const64 [d])) -> (Const64 [c << uint64(d)]) 81 (Rsh64x64 (Const64 [c]) (Const64 [d])) -> (Const64 [c >> uint64(d)]) 82 (Rsh64Ux64 (Const64 [c]) (Const64 [d])) -> (Const64 [int64(uint64(c) >> uint64(d))]) 83 (Lsh32x64 (Const32 [c]) (Const64 [d])) -> (Const32 [int64(int32(c) << uint64(d))]) 84 (Rsh32x64 (Const32 [c]) (Const64 [d])) -> (Const32 [int64(int32(c) >> uint64(d))]) 85 (Rsh32Ux64 (Const32 [c]) (Const64 [d])) -> (Const32 [int64(int32(uint32(c) >> uint64(d)))]) 86 (Lsh16x64 (Const16 [c]) (Const64 [d])) -> (Const16 [int64(int16(c) << uint64(d))]) 87 (Rsh16x64 (Const16 [c]) (Const64 [d])) -> (Const16 [int64(int16(c) >> uint64(d))]) 88 (Rsh16Ux64 (Const16 [c]) (Const64 [d])) -> (Const16 [int64(int16(uint16(c) >> uint64(d)))]) 89 (Lsh8x64 (Const8 [c]) (Const64 [d])) -> (Const8 [int64(int8(c) << uint64(d))]) 90 (Rsh8x64 (Const8 [c]) (Const64 [d])) -> (Const8 [int64(int8(c) >> uint64(d))]) 91 (Rsh8Ux64 (Const8 [c]) (Const64 [d])) -> (Const8 [int64(int8(uint8(c) >> uint64(d)))]) 92 93 // Fold IsInBounds when the range of the index cannot exceed the limit. 94 (IsInBounds (ZeroExt8to32 _) (Const32 [c])) && (1 << 8) <= c -> (ConstBool [1]) 95 (IsInBounds (ZeroExt8to64 _) (Const64 [c])) && (1 << 8) <= c -> (ConstBool [1]) 96 (IsInBounds (ZeroExt16to32 _) (Const32 [c])) && (1 << 16) <= c -> (ConstBool [1]) 97 (IsInBounds (ZeroExt16to64 _) (Const64 [c])) && (1 << 16) <= c -> (ConstBool [1]) 98 (IsInBounds x x) -> (ConstBool [0]) 99 (IsInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c < d -> (ConstBool [1]) 100 (IsInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c < d -> (ConstBool [1]) 101 (IsInBounds (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(0 <= c && c < d)]) 102 (IsInBounds (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(0 <= c && c < d)]) 103 // (Mod64u x y) is always between 0 (inclusive) and y (exclusive). 104 (IsInBounds (Mod32u _ y) y) -> (ConstBool [1]) 105 (IsInBounds (Mod64u _ y) y) -> (ConstBool [1]) 106 107 (IsSliceInBounds x x) -> (ConstBool [1]) 108 (IsSliceInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c <= d -> (ConstBool [1]) 109 (IsSliceInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c <= d -> (ConstBool [1]) 110 (IsSliceInBounds (Const32 [0]) _) -> (ConstBool [1]) 111 (IsSliceInBounds (Const64 [0]) _) -> (ConstBool [1]) 112 (IsSliceInBounds (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(0 <= c && c <= d)]) 113 (IsSliceInBounds (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(0 <= c && c <= d)]) 114 (IsSliceInBounds (SliceLen x) (SliceCap x)) -> (ConstBool [1]) 115 116 (Eq64 x x) -> (ConstBool [1]) 117 (Eq32 x x) -> (ConstBool [1]) 118 (Eq16 x x) -> (ConstBool [1]) 119 (Eq8 x x) -> (ConstBool [1]) 120 (EqB (ConstBool [c]) (ConstBool [d])) -> (ConstBool [b2i(c == d)]) 121 (EqB (ConstBool [0]) x) -> (Not x) 122 (EqB (ConstBool [1]) x) -> x 123 124 (Neq64 x x) -> (ConstBool [0]) 125 (Neq32 x x) -> (ConstBool [0]) 126 (Neq16 x x) -> (ConstBool [0]) 127 (Neq8 x x) -> (ConstBool [0]) 128 (NeqB (ConstBool [c]) (ConstBool [d])) -> (ConstBool [b2i(c != d)]) 129 (NeqB (ConstBool [0]) x) -> x 130 (NeqB (ConstBool [1]) x) -> (Not x) 131 132 (Eq64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) -> (Eq64 (Const64 <t> [c-d]) x) 133 (Eq32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) -> (Eq32 (Const32 <t> [int64(int32(c-d))]) x) 134 (Eq16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) -> (Eq16 (Const16 <t> [int64(int16(c-d))]) x) 135 (Eq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) -> (Eq8 (Const8 <t> [int64(int8(c-d))]) x) 136 137 (Neq64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) -> (Neq64 (Const64 <t> [c-d]) x) 138 (Neq32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) -> (Neq32 (Const32 <t> [int64(int32(c-d))]) x) 139 (Neq16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) -> (Neq16 (Const16 <t> [int64(int16(c-d))]) x) 140 (Neq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) -> (Neq8 (Const8 <t> [int64(int8(c-d))]) x) 141 142 // canonicalize: swap arguments for commutative operations when one argument is a constant. 143 (Eq64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (Eq64 (Const64 <t> [c]) x) 144 (Eq32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (Eq32 (Const32 <t> [c]) x) 145 (Eq16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (Eq16 (Const16 <t> [c]) x) 146 (Eq8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (Eq8 (Const8 <t> [c]) x) 147 148 (Neq64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (Neq64 (Const64 <t> [c]) x) 149 (Neq32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (Neq32 (Const32 <t> [c]) x) 150 (Neq16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (Neq16 (Const16 <t> [c]) x) 151 (Neq8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (Neq8 (Const8 <t> [c]) x) 152 153 // AddPtr is not canonicalized because nilcheck ptr checks the first argument to be non-nil. 154 (Add64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (Add64 (Const64 <t> [c]) x) 155 (Add32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (Add32 (Const32 <t> [c]) x) 156 (Add16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (Add16 (Const16 <t> [c]) x) 157 (Add8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (Add8 (Const8 <t> [c]) x) 158 159 (Mul64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (Mul64 (Const64 <t> [c]) x) 160 (Mul32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (Mul32 (Const32 <t> [c]) x) 161 (Mul16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (Mul16 (Const16 <t> [c]) x) 162 (Mul8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (Mul8 (Const8 <t> [c]) x) 163 164 (Sub64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (Add64 (Const64 <t> [-c]) x) 165 (Sub32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (Add32 (Const32 <t> [int64(int32(-c))]) x) 166 (Sub16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (Add16 (Const16 <t> [int64(int16(-c))]) x) 167 (Sub8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (Add8 (Const8 <t> [int64(int8(-c))]) x) 168 169 (And64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (And64 (Const64 <t> [c]) x) 170 (And32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (And32 (Const32 <t> [c]) x) 171 (And16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (And16 (Const16 <t> [c]) x) 172 (And8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (And8 (Const8 <t> [c]) x) 173 174 (Or64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (Or64 (Const64 <t> [c]) x) 175 (Or32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (Or32 (Const32 <t> [c]) x) 176 (Or16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (Or16 (Const16 <t> [c]) x) 177 (Or8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (Or8 (Const8 <t> [c]) x) 178 179 (Xor64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (Xor64 (Const64 <t> [c]) x) 180 (Xor32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (Xor32 (Const32 <t> [c]) x) 181 (Xor16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (Xor16 (Const16 <t> [c]) x) 182 (Xor8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (Xor8 (Const8 <t> [c]) x) 183 184 // Distribute multiplication c * (d+x) -> c*d + c*x. Useful for: 185 // a[i].b = ...; a[i+1].b = ... 186 (Mul64 (Const64 <t> [c]) (Add64 <t> (Const64 <t> [d]) x)) -> 187 (Add64 (Const64 <t> [c*d]) (Mul64 <t> (Const64 <t> [c]) x)) 188 (Mul32 (Const32 <t> [c]) (Add32 <t> (Const32 <t> [d]) x)) -> 189 (Add32 (Const32 <t> [int64(int32(c*d))]) (Mul32 <t> (Const32 <t> [c]) x)) 190 191 // rewrite shifts of 8/16/32 bit consts into 64 bit consts to reduce 192 // the number of the other rewrite rules for const shifts 193 (Lsh64x32 <t> x (Const32 [c])) -> (Lsh64x64 x (Const64 <t> [int64(uint32(c))])) 194 (Lsh64x16 <t> x (Const16 [c])) -> (Lsh64x64 x (Const64 <t> [int64(uint16(c))])) 195 (Lsh64x8 <t> x (Const8 [c])) -> (Lsh64x64 x (Const64 <t> [int64(uint8(c))])) 196 (Rsh64x32 <t> x (Const32 [c])) -> (Rsh64x64 x (Const64 <t> [int64(uint32(c))])) 197 (Rsh64x16 <t> x (Const16 [c])) -> (Rsh64x64 x (Const64 <t> [int64(uint16(c))])) 198 (Rsh64x8 <t> x (Const8 [c])) -> (Rsh64x64 x (Const64 <t> [int64(uint8(c))])) 199 (Rsh64Ux32 <t> x (Const32 [c])) -> (Rsh64Ux64 x (Const64 <t> [int64(uint32(c))])) 200 (Rsh64Ux16 <t> x (Const16 [c])) -> (Rsh64Ux64 x (Const64 <t> [int64(uint16(c))])) 201 (Rsh64Ux8 <t> x (Const8 [c])) -> (Rsh64Ux64 x (Const64 <t> [int64(uint8(c))])) 202 203 (Lsh32x32 <t> x (Const32 [c])) -> (Lsh32x64 x (Const64 <t> [int64(uint32(c))])) 204 (Lsh32x16 <t> x (Const16 [c])) -> (Lsh32x64 x (Const64 <t> [int64(uint16(c))])) 205 (Lsh32x8 <t> x (Const8 [c])) -> (Lsh32x64 x (Const64 <t> [int64(uint8(c))])) 206 (Rsh32x32 <t> x (Const32 [c])) -> (Rsh32x64 x (Const64 <t> [int64(uint32(c))])) 207 (Rsh32x16 <t> x (Const16 [c])) -> (Rsh32x64 x (Const64 <t> [int64(uint16(c))])) 208 (Rsh32x8 <t> x (Const8 [c])) -> (Rsh32x64 x (Const64 <t> [int64(uint8(c))])) 209 (Rsh32Ux32 <t> x (Const32 [c])) -> (Rsh32Ux64 x (Const64 <t> [int64(uint32(c))])) 210 (Rsh32Ux16 <t> x (Const16 [c])) -> (Rsh32Ux64 x (Const64 <t> [int64(uint16(c))])) 211 (Rsh32Ux8 <t> x (Const8 [c])) -> (Rsh32Ux64 x (Const64 <t> [int64(uint8(c))])) 212 213 (Lsh16x32 <t> x (Const32 [c])) -> (Lsh16x64 x (Const64 <t> [int64(uint32(c))])) 214 (Lsh16x16 <t> x (Const16 [c])) -> (Lsh16x64 x (Const64 <t> [int64(uint16(c))])) 215 (Lsh16x8 <t> x (Const8 [c])) -> (Lsh16x64 x (Const64 <t> [int64(uint8(c))])) 216 (Rsh16x32 <t> x (Const32 [c])) -> (Rsh16x64 x (Const64 <t> [int64(uint32(c))])) 217 (Rsh16x16 <t> x (Const16 [c])) -> (Rsh16x64 x (Const64 <t> [int64(uint16(c))])) 218 (Rsh16x8 <t> x (Const8 [c])) -> (Rsh16x64 x (Const64 <t> [int64(uint8(c))])) 219 (Rsh16Ux32 <t> x (Const32 [c])) -> (Rsh16Ux64 x (Const64 <t> [int64(uint32(c))])) 220 (Rsh16Ux16 <t> x (Const16 [c])) -> (Rsh16Ux64 x (Const64 <t> [int64(uint16(c))])) 221 (Rsh16Ux8 <t> x (Const8 [c])) -> (Rsh16Ux64 x (Const64 <t> [int64(uint8(c))])) 222 223 (Lsh8x32 <t> x (Const32 [c])) -> (Lsh8x64 x (Const64 <t> [int64(uint32(c))])) 224 (Lsh8x16 <t> x (Const16 [c])) -> (Lsh8x64 x (Const64 <t> [int64(uint16(c))])) 225 (Lsh8x8 <t> x (Const8 [c])) -> (Lsh8x64 x (Const64 <t> [int64(uint8(c))])) 226 (Rsh8x32 <t> x (Const32 [c])) -> (Rsh8x64 x (Const64 <t> [int64(uint32(c))])) 227 (Rsh8x16 <t> x (Const16 [c])) -> (Rsh8x64 x (Const64 <t> [int64(uint16(c))])) 228 (Rsh8x8 <t> x (Const8 [c])) -> (Rsh8x64 x (Const64 <t> [int64(uint8(c))])) 229 (Rsh8Ux32 <t> x (Const32 [c])) -> (Rsh8Ux64 x (Const64 <t> [int64(uint32(c))])) 230 (Rsh8Ux16 <t> x (Const16 [c])) -> (Rsh8Ux64 x (Const64 <t> [int64(uint16(c))])) 231 (Rsh8Ux8 <t> x (Const8 [c])) -> (Rsh8Ux64 x (Const64 <t> [int64(uint8(c))])) 232 233 // shifts by zero 234 (Lsh64x64 x (Const64 [0])) -> x 235 (Rsh64x64 x (Const64 [0])) -> x 236 (Rsh64Ux64 x (Const64 [0])) -> x 237 (Lsh32x64 x (Const64 [0])) -> x 238 (Rsh32x64 x (Const64 [0])) -> x 239 (Rsh32Ux64 x (Const64 [0])) -> x 240 (Lsh16x64 x (Const64 [0])) -> x 241 (Rsh16x64 x (Const64 [0])) -> x 242 (Rsh16Ux64 x (Const64 [0])) -> x 243 (Lsh8x64 x (Const64 [0])) -> x 244 (Rsh8x64 x (Const64 [0])) -> x 245 (Rsh8Ux64 x (Const64 [0])) -> x 246 247 // zero shifted. 248 (Lsh64x64 (Const64 [0]) _) -> (Const64 [0]) 249 (Lsh64x32 (Const64 [0]) _) -> (Const64 [0]) 250 (Lsh64x16 (Const64 [0]) _) -> (Const64 [0]) 251 (Lsh64x8 (Const64 [0]) _) -> (Const64 [0]) 252 (Rsh64x64 (Const64 [0]) _) -> (Const64 [0]) 253 (Rsh64x32 (Const64 [0]) _) -> (Const64 [0]) 254 (Rsh64x16 (Const64 [0]) _) -> (Const64 [0]) 255 (Rsh64x8 (Const64 [0]) _) -> (Const64 [0]) 256 (Rsh64Ux64 (Const64 [0]) _) -> (Const64 [0]) 257 (Rsh64Ux32 (Const64 [0]) _) -> (Const64 [0]) 258 (Rsh64Ux16 (Const64 [0]) _) -> (Const64 [0]) 259 (Rsh64Ux8 (Const64 [0]) _) -> (Const64 [0]) 260 (Lsh32x64 (Const32 [0]) _) -> (Const32 [0]) 261 (Lsh32x32 (Const32 [0]) _) -> (Const32 [0]) 262 (Lsh32x16 (Const32 [0]) _) -> (Const32 [0]) 263 (Lsh32x8 (Const32 [0]) _) -> (Const32 [0]) 264 (Rsh32x64 (Const32 [0]) _) -> (Const32 [0]) 265 (Rsh32x32 (Const32 [0]) _) -> (Const32 [0]) 266 (Rsh32x16 (Const32 [0]) _) -> (Const32 [0]) 267 (Rsh32x8 (Const32 [0]) _) -> (Const32 [0]) 268 (Rsh32Ux64 (Const32 [0]) _) -> (Const32 [0]) 269 (Rsh32Ux32 (Const32 [0]) _) -> (Const32 [0]) 270 (Rsh32Ux16 (Const32 [0]) _) -> (Const32 [0]) 271 (Rsh32Ux8 (Const32 [0]) _) -> (Const32 [0]) 272 (Lsh16x64 (Const16 [0]) _) -> (Const16 [0]) 273 (Lsh16x32 (Const16 [0]) _) -> (Const16 [0]) 274 (Lsh16x16 (Const16 [0]) _) -> (Const16 [0]) 275 (Lsh16x8 (Const16 [0]) _) -> (Const16 [0]) 276 (Rsh16x64 (Const16 [0]) _) -> (Const16 [0]) 277 (Rsh16x32 (Const16 [0]) _) -> (Const16 [0]) 278 (Rsh16x16 (Const16 [0]) _) -> (Const16 [0]) 279 (Rsh16x8 (Const16 [0]) _) -> (Const16 [0]) 280 (Rsh16Ux64 (Const16 [0]) _) -> (Const16 [0]) 281 (Rsh16Ux32 (Const16 [0]) _) -> (Const16 [0]) 282 (Rsh16Ux16 (Const16 [0]) _) -> (Const16 [0]) 283 (Rsh16Ux8 (Const16 [0]) _) -> (Const16 [0]) 284 (Lsh8x64 (Const8 [0]) _) -> (Const8 [0]) 285 (Lsh8x32 (Const8 [0]) _) -> (Const8 [0]) 286 (Lsh8x16 (Const8 [0]) _) -> (Const8 [0]) 287 (Lsh8x8 (Const8 [0]) _) -> (Const8 [0]) 288 (Rsh8x64 (Const8 [0]) _) -> (Const8 [0]) 289 (Rsh8x32 (Const8 [0]) _) -> (Const8 [0]) 290 (Rsh8x16 (Const8 [0]) _) -> (Const8 [0]) 291 (Rsh8x8 (Const8 [0]) _) -> (Const8 [0]) 292 (Rsh8Ux64 (Const8 [0]) _) -> (Const8 [0]) 293 (Rsh8Ux32 (Const8 [0]) _) -> (Const8 [0]) 294 (Rsh8Ux16 (Const8 [0]) _) -> (Const8 [0]) 295 (Rsh8Ux8 (Const8 [0]) _) -> (Const8 [0]) 296 297 // large left shifts of all values, and right shifts of unsigned values 298 (Lsh64x64 _ (Const64 [c])) && uint64(c) >= 64 -> (Const64 [0]) 299 (Rsh64Ux64 _ (Const64 [c])) && uint64(c) >= 64 -> (Const64 [0]) 300 (Lsh32x64 _ (Const64 [c])) && uint64(c) >= 32 -> (Const32 [0]) 301 (Rsh32Ux64 _ (Const64 [c])) && uint64(c) >= 32 -> (Const32 [0]) 302 (Lsh16x64 _ (Const64 [c])) && uint64(c) >= 16 -> (Const16 [0]) 303 (Rsh16Ux64 _ (Const64 [c])) && uint64(c) >= 16 -> (Const16 [0]) 304 (Lsh8x64 _ (Const64 [c])) && uint64(c) >= 8 -> (Const8 [0]) 305 (Rsh8Ux64 _ (Const64 [c])) && uint64(c) >= 8 -> (Const8 [0]) 306 307 // combine const shifts 308 (Lsh64x64 <t> (Lsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Lsh64x64 x (Const64 <t> [c+d])) 309 (Lsh32x64 <t> (Lsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Lsh32x64 x (Const64 <t> [c+d])) 310 (Lsh16x64 <t> (Lsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Lsh16x64 x (Const64 <t> [c+d])) 311 (Lsh8x64 <t> (Lsh8x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Lsh8x64 x (Const64 <t> [c+d])) 312 313 (Rsh64x64 <t> (Rsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh64x64 x (Const64 <t> [c+d])) 314 (Rsh32x64 <t> (Rsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh32x64 x (Const64 <t> [c+d])) 315 (Rsh16x64 <t> (Rsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh16x64 x (Const64 <t> [c+d])) 316 (Rsh8x64 <t> (Rsh8x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh8x64 x (Const64 <t> [c+d])) 317 318 (Rsh64Ux64 <t> (Rsh64Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh64Ux64 x (Const64 <t> [c+d])) 319 (Rsh32Ux64 <t> (Rsh32Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh32Ux64 x (Const64 <t> [c+d])) 320 (Rsh16Ux64 <t> (Rsh16Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh16Ux64 x (Const64 <t> [c+d])) 321 (Rsh8Ux64 <t> (Rsh8Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh8Ux64 x (Const64 <t> [c+d])) 322 323 // ((x >> c1) << c2) >> c3 324 (Rsh64Ux64 (Lsh64x64 (Rsh64Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 325 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 326 -> (Rsh64Ux64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3])) 327 (Rsh32Ux64 (Lsh32x64 (Rsh32Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 328 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 329 -> (Rsh32Ux64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3])) 330 (Rsh16Ux64 (Lsh16x64 (Rsh16Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 331 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 332 -> (Rsh16Ux64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3])) 333 (Rsh8Ux64 (Lsh8x64 (Rsh8Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 334 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 335 -> (Rsh8Ux64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3])) 336 337 // ((x << c1) >> c2) << c3 338 (Lsh64x64 (Rsh64Ux64 (Lsh64x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 339 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 340 -> (Lsh64x64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3])) 341 (Lsh32x64 (Rsh32Ux64 (Lsh32x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 342 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 343 -> (Lsh32x64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3])) 344 (Lsh16x64 (Rsh16Ux64 (Lsh16x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 345 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 346 -> (Lsh16x64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3])) 347 (Lsh8x64 (Rsh8Ux64 (Lsh8x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 348 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 349 -> (Lsh8x64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3])) 350 351 // constant comparisons 352 (Eq64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c == d)]) 353 (Eq32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c == d)]) 354 (Eq16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c == d)]) 355 (Eq8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c == d)]) 356 357 (Neq64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c != d)]) 358 (Neq32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c != d)]) 359 (Neq16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c != d)]) 360 (Neq8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c != d)]) 361 362 (Greater64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c > d)]) 363 (Greater32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c > d)]) 364 (Greater16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c > d)]) 365 (Greater8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c > d)]) 366 367 (Greater64U (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(uint64(c) > uint64(d))]) 368 (Greater32U (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(uint32(c) > uint32(d))]) 369 (Greater16U (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(uint16(c) > uint16(d))]) 370 (Greater8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) > uint8(d))]) 371 372 (Geq64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c >= d)]) 373 (Geq32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c >= d)]) 374 (Geq16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c >= d)]) 375 (Geq8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c >= d)]) 376 377 (Geq64U (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(uint64(c) >= uint64(d))]) 378 (Geq32U (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(uint32(c) >= uint32(d))]) 379 (Geq16U (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(uint16(c) >= uint16(d))]) 380 (Geq8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) >= uint8(d))]) 381 382 (Less64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c < d)]) 383 (Less32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c < d)]) 384 (Less16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c < d)]) 385 (Less8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c < d)]) 386 387 (Less64U (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(uint64(c) < uint64(d))]) 388 (Less32U (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(uint32(c) < uint32(d))]) 389 (Less16U (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(uint16(c) < uint16(d))]) 390 (Less8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) < uint8(d))]) 391 392 (Leq64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c <= d)]) 393 (Leq32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c <= d)]) 394 (Leq16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c <= d)]) 395 (Leq8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c <= d)]) 396 397 (Leq64U (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(uint64(c) <= uint64(d))]) 398 (Leq32U (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(uint32(c) <= uint32(d))]) 399 (Leq16U (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(uint16(c) <= uint16(d))]) 400 (Leq8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) <= uint8(d))]) 401 402 // simplifications 403 (Or64 x x) -> x 404 (Or32 x x) -> x 405 (Or16 x x) -> x 406 (Or8 x x) -> x 407 (Or64 (Const64 [0]) x) -> x 408 (Or32 (Const32 [0]) x) -> x 409 (Or16 (Const16 [0]) x) -> x 410 (Or8 (Const8 [0]) x) -> x 411 (Or64 (Const64 [-1]) _) -> (Const64 [-1]) 412 (Or32 (Const32 [-1]) _) -> (Const32 [-1]) 413 (Or16 (Const16 [-1]) _) -> (Const16 [-1]) 414 (Or8 (Const8 [-1]) _) -> (Const8 [-1]) 415 (And64 x x) -> x 416 (And32 x x) -> x 417 (And16 x x) -> x 418 (And8 x x) -> x 419 (And64 (Const64 [-1]) x) -> x 420 (And32 (Const32 [-1]) x) -> x 421 (And16 (Const16 [-1]) x) -> x 422 (And8 (Const8 [-1]) x) -> x 423 (And64 (Const64 [0]) _) -> (Const64 [0]) 424 (And32 (Const32 [0]) _) -> (Const32 [0]) 425 (And16 (Const16 [0]) _) -> (Const16 [0]) 426 (And8 (Const8 [0]) _) -> (Const8 [0]) 427 (Xor64 x x) -> (Const64 [0]) 428 (Xor32 x x) -> (Const32 [0]) 429 (Xor16 x x) -> (Const16 [0]) 430 (Xor8 x x) -> (Const8 [0]) 431 (Xor64 (Const64 [0]) x) -> x 432 (Xor32 (Const32 [0]) x) -> x 433 (Xor16 (Const16 [0]) x) -> x 434 (Xor8 (Const8 [0]) x) -> x 435 (Add64 (Const64 [0]) x) -> x 436 (Add32 (Const32 [0]) x) -> x 437 (Add16 (Const16 [0]) x) -> x 438 (Add8 (Const8 [0]) x) -> x 439 (Sub64 x x) -> (Const64 [0]) 440 (Sub32 x x) -> (Const32 [0]) 441 (Sub16 x x) -> (Const16 [0]) 442 (Sub8 x x) -> (Const8 [0]) 443 (Mul64 (Const64 [0]) _) -> (Const64 [0]) 444 (Mul32 (Const32 [0]) _) -> (Const32 [0]) 445 (Mul16 (Const16 [0]) _) -> (Const16 [0]) 446 (Mul8 (Const8 [0]) _) -> (Const8 [0]) 447 (Com8 (Com8 x)) -> x 448 (Com16 (Com16 x)) -> x 449 (Com32 (Com32 x)) -> x 450 (Com64 (Com64 x)) -> x 451 (Neg8 (Sub8 x y)) -> (Sub8 y x) 452 (Neg16 (Sub16 x y)) -> (Sub16 y x) 453 (Neg32 (Sub32 x y)) -> (Sub32 y x) 454 (Neg64 (Sub64 x y)) -> (Sub64 y x) 455 456 (And64 x (And64 x y)) -> (And64 x y) 457 (And32 x (And32 x y)) -> (And32 x y) 458 (And16 x (And16 x y)) -> (And16 x y) 459 (And8 x (And8 x y)) -> (And8 x y) 460 (And64 x (And64 y x)) -> (And64 x y) 461 (And32 x (And32 y x)) -> (And32 x y) 462 (And16 x (And16 y x)) -> (And16 x y) 463 (And8 x (And8 y x)) -> (And8 x y) 464 (And64 (And64 x y) x) -> (And64 x y) 465 (And32 (And32 x y) x) -> (And32 x y) 466 (And16 (And16 x y) x) -> (And16 x y) 467 (And8 (And8 x y) x) -> (And8 x y) 468 (And64 (And64 x y) y) -> (And64 x y) 469 (And32 (And32 x y) y) -> (And32 x y) 470 (And16 (And16 x y) y) -> (And16 x y) 471 (And8 (And8 x y) y) -> (And8 x y) 472 (Or64 x (Or64 x y)) -> (Or64 x y) 473 (Or32 x (Or32 x y)) -> (Or32 x y) 474 (Or16 x (Or16 x y)) -> (Or16 x y) 475 (Or8 x (Or8 x y)) -> (Or8 x y) 476 (Or64 x (Or64 y x)) -> (Or64 x y) 477 (Or32 x (Or32 y x)) -> (Or32 x y) 478 (Or16 x (Or16 y x)) -> (Or16 x y) 479 (Or8 x (Or8 y x)) -> (Or8 x y) 480 (Or64 (Or64 x y) x) -> (Or64 x y) 481 (Or32 (Or32 x y) x) -> (Or32 x y) 482 (Or16 (Or16 x y) x) -> (Or16 x y) 483 (Or8 (Or8 x y) x) -> (Or8 x y) 484 (Or64 (Or64 x y) y) -> (Or64 x y) 485 (Or32 (Or32 x y) y) -> (Or32 x y) 486 (Or16 (Or16 x y) y) -> (Or16 x y) 487 (Or8 (Or8 x y) y) -> (Or8 x y) 488 (Xor64 x (Xor64 x y)) -> y 489 (Xor32 x (Xor32 x y)) -> y 490 (Xor16 x (Xor16 x y)) -> y 491 (Xor8 x (Xor8 x y)) -> y 492 (Xor64 x (Xor64 y x)) -> y 493 (Xor32 x (Xor32 y x)) -> y 494 (Xor16 x (Xor16 y x)) -> y 495 (Xor8 x (Xor8 y x)) -> y 496 (Xor64 (Xor64 x y) x) -> y 497 (Xor32 (Xor32 x y) x) -> y 498 (Xor16 (Xor16 x y) x) -> y 499 (Xor8 (Xor8 x y) x) -> y 500 (Xor64 (Xor64 x y) y) -> x 501 (Xor32 (Xor32 x y) y) -> x 502 (Xor16 (Xor16 x y) y) -> x 503 (Xor8 (Xor8 x y) y) -> x 504 505 (Trunc64to8 (And64 (Const64 [y]) x)) && y&0xFF == 0xFF -> (Trunc64to8 x) 506 (Trunc64to16 (And64 (Const64 [y]) x)) && y&0xFFFF == 0xFFFF -> (Trunc64to16 x) 507 (Trunc64to32 (And64 (Const64 [y]) x)) && y&0xFFFFFFFF == 0xFFFFFFFF -> (Trunc64to32 x) 508 (Trunc32to8 (And32 (Const32 [y]) x)) && y&0xFF == 0xFF -> (Trunc32to8 x) 509 (Trunc32to16 (And32 (Const32 [y]) x)) && y&0xFFFF == 0xFFFF -> (Trunc32to16 x) 510 (Trunc16to8 (And16 (Const16 [y]) x)) && y&0xFF == 0xFF -> (Trunc16to8 x) 511 512 // Rewrite AND of consts as shifts if possible, slightly faster for 64 bit operands 513 // leading zeros can be shifted left, then right 514 (And64 <t> (Const64 [y]) x) && nlz(y) + nto(y) == 64 && nto(y) >= 32 515 -> (Rsh64Ux64 (Lsh64x64 <t> x (Const64 <t> [nlz(y)])) (Const64 <t> [nlz(y)])) 516 // trailing zeros can be shifted right, then left 517 (And64 <t> (Const64 [y]) x) && nlo(y) + ntz(y) == 64 && ntz(y) >= 32 518 -> (Lsh64x64 (Rsh64Ux64 <t> x (Const64 <t> [ntz(y)])) (Const64 <t> [ntz(y)])) 519 520 // simplifications often used for lengths. e.g. len(s[i:i+5])==5 521 (Sub64 (Add64 x y) x) -> y 522 (Sub64 (Add64 x y) y) -> x 523 (Sub32 (Add32 x y) x) -> y 524 (Sub32 (Add32 x y) y) -> x 525 (Sub16 (Add16 x y) x) -> y 526 (Sub16 (Add16 x y) y) -> x 527 (Sub8 (Add8 x y) x) -> y 528 (Sub8 (Add8 x y) y) -> x 529 530 // basic phi simplifications 531 (Phi (Const8 [c]) (Const8 [c])) -> (Const8 [c]) 532 (Phi (Const16 [c]) (Const16 [c])) -> (Const16 [c]) 533 (Phi (Const32 [c]) (Const32 [c])) -> (Const32 [c]) 534 (Phi (Const64 [c]) (Const64 [c])) -> (Const64 [c]) 535 536 // user nil checks 537 (NeqPtr p (ConstNil)) -> (IsNonNil p) 538 (NeqPtr (ConstNil) p) -> (IsNonNil p) 539 (EqPtr p (ConstNil)) -> (Not (IsNonNil p)) 540 (EqPtr (ConstNil) p) -> (Not (IsNonNil p)) 541 542 // slice and interface comparisons 543 // The frontend ensures that we can only compare against nil, 544 // so we need only compare the first word (interface type or slice ptr). 545 (EqInter x y) -> (EqPtr (ITab x) (ITab y)) 546 (NeqInter x y) -> (NeqPtr (ITab x) (ITab y)) 547 (EqSlice x y) -> (EqPtr (SlicePtr x) (SlicePtr y)) 548 (NeqSlice x y) -> (NeqPtr (SlicePtr x) (SlicePtr y)) 549 550 // Load of store of same address, with compatibly typed value and same size 551 (Load <t1> p1 (Store [w] p2 x _)) && isSamePtr(p1,p2) && t1.Compare(x.Type)==CMPeq && w == t1.Size() -> x 552 553 // Collapse OffPtr 554 (OffPtr (OffPtr p [b]) [a]) -> (OffPtr p [a+b]) 555 (OffPtr p [0]) && v.Type.Compare(p.Type) == CMPeq -> p 556 557 // indexing operations 558 // Note: bounds check has already been done 559 (ArrayIndex <t> [0] x:(Load ptr mem)) -> @x.Block (Load <t> ptr mem) 560 (PtrIndex <t> ptr idx) && config.PtrSize == 4 -> (AddPtr ptr (Mul32 <config.fe.TypeInt()> idx (Const32 <config.fe.TypeInt()> [t.ElemType().Size()]))) 561 (PtrIndex <t> ptr idx) && config.PtrSize == 8 -> (AddPtr ptr (Mul64 <config.fe.TypeInt()> idx (Const64 <config.fe.TypeInt()> [t.ElemType().Size()]))) 562 563 // struct operations 564 (StructSelect (StructMake1 x)) -> x 565 (StructSelect [0] (StructMake2 x _)) -> x 566 (StructSelect [1] (StructMake2 _ x)) -> x 567 (StructSelect [0] (StructMake3 x _ _)) -> x 568 (StructSelect [1] (StructMake3 _ x _)) -> x 569 (StructSelect [2] (StructMake3 _ _ x)) -> x 570 (StructSelect [0] (StructMake4 x _ _ _)) -> x 571 (StructSelect [1] (StructMake4 _ x _ _)) -> x 572 (StructSelect [2] (StructMake4 _ _ x _)) -> x 573 (StructSelect [3] (StructMake4 _ _ _ x)) -> x 574 575 (Load <t> _ _) && t.IsStruct() && t.NumFields() == 0 && config.fe.CanSSA(t) -> 576 (StructMake0) 577 (Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 1 && config.fe.CanSSA(t) -> 578 (StructMake1 579 (Load <t.FieldType(0)> ptr mem)) 580 (Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 2 && config.fe.CanSSA(t) -> 581 (StructMake2 582 (Load <t.FieldType(0)> ptr mem) 583 (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem)) 584 (Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 3 && config.fe.CanSSA(t) -> 585 (StructMake3 586 (Load <t.FieldType(0)> ptr mem) 587 (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem) 588 (Load <t.FieldType(2)> (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] ptr) mem)) 589 (Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 4 && config.fe.CanSSA(t) -> 590 (StructMake4 591 (Load <t.FieldType(0)> ptr mem) 592 (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem) 593 (Load <t.FieldType(2)> (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] ptr) mem) 594 (Load <t.FieldType(3)> (OffPtr <t.FieldType(3).PtrTo()> [t.FieldOff(3)] ptr) mem)) 595 596 (StructSelect [i] x:(Load <t> ptr mem)) && !config.fe.CanSSA(t) -> 597 @x.Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [t.FieldOff(int(i))] ptr) mem) 598 599 (Store _ (StructMake0) mem) -> mem 600 (Store dst (StructMake1 <t> f0) mem) -> 601 (Store [t.FieldType(0).Size()] dst f0 mem) 602 (Store dst (StructMake2 <t> f0 f1) mem) -> 603 (Store [t.FieldType(1).Size()] 604 (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst) 605 f1 606 (Store [t.FieldType(0).Size()] dst f0 mem)) 607 (Store dst (StructMake3 <t> f0 f1 f2) mem) -> 608 (Store [t.FieldType(2).Size()] 609 (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] dst) 610 f2 611 (Store [t.FieldType(1).Size()] 612 (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst) 613 f1 614 (Store [t.FieldType(0).Size()] dst f0 mem))) 615 (Store dst (StructMake4 <t> f0 f1 f2 f3) mem) -> 616 (Store [t.FieldType(3).Size()] 617 (OffPtr <t.FieldType(3).PtrTo()> [t.FieldOff(3)] dst) 618 f3 619 (Store [t.FieldType(2).Size()] 620 (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] dst) 621 f2 622 (Store [t.FieldType(1).Size()] 623 (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst) 624 f1 625 (Store [t.FieldType(0).Size()] dst f0 mem)))) 626 627 // un-SSAable values use mem->mem copies 628 (Store [size] dst (Load <t> src mem) mem) && !config.fe.CanSSA(t) -> (Move [size] dst src mem) 629 (Store [size] dst (Load <t> src mem) (VarDef {x} mem)) && !config.fe.CanSSA(t) -> (Move [size] dst src (VarDef {x} mem)) 630 631 // string ops 632 // Decomposing StringMake and lowering of StringPtr and StringLen 633 // happens in a later pass, dec, so that these operations are available 634 // to other passes for optimizations. 635 (StringPtr (StringMake (Const64 <t> [c]) _)) -> (Const64 <t> [c]) 636 (StringLen (StringMake _ (Const64 <t> [c]))) -> (Const64 <t> [c]) 637 (ConstString {s}) && config.PtrSize == 4 && s.(string) == "" -> 638 (StringMake (ConstNil) (Const32 <config.fe.TypeInt()> [0])) 639 (ConstString {s}) && config.PtrSize == 8 && s.(string) == "" -> 640 (StringMake (ConstNil) (Const64 <config.fe.TypeInt()> [0])) 641 (ConstString {s}) && config.PtrSize == 4 && s.(string) != "" -> 642 (StringMake 643 (Addr <config.fe.TypeBytePtr()> {config.fe.StringData(s.(string))} 644 (SB)) 645 (Const32 <config.fe.TypeInt()> [int64(len(s.(string)))])) 646 (ConstString {s}) && config.PtrSize == 8 && s.(string) != "" -> 647 (StringMake 648 (Addr <config.fe.TypeBytePtr()> {config.fe.StringData(s.(string))} 649 (SB)) 650 (Const64 <config.fe.TypeInt()> [int64(len(s.(string)))])) 651 652 // slice ops 653 // Only a few slice rules are provided here. See dec.rules for 654 // a more comprehensive set. 655 (SliceLen (SliceMake _ (Const64 <t> [c]) _)) -> (Const64 <t> [c]) 656 (SliceCap (SliceMake _ _ (Const64 <t> [c]))) -> (Const64 <t> [c]) 657 (SlicePtr (SliceMake (SlicePtr x) _ _)) -> (SlicePtr x) 658 (SliceLen (SliceMake _ (SliceLen x) _)) -> (SliceLen x) 659 (SliceCap (SliceMake _ _ (SliceCap x))) -> (SliceCap x) 660 (SliceCap (SliceMake _ _ (SliceLen x))) -> (SliceLen x) 661 (ConstSlice) && config.PtrSize == 4 -> 662 (SliceMake 663 (ConstNil <v.Type.ElemType().PtrTo()>) 664 (Const32 <config.fe.TypeInt()> [0]) 665 (Const32 <config.fe.TypeInt()> [0])) 666 (ConstSlice) && config.PtrSize == 8 -> 667 (SliceMake 668 (ConstNil <v.Type.ElemType().PtrTo()>) 669 (Const64 <config.fe.TypeInt()> [0]) 670 (Const64 <config.fe.TypeInt()> [0])) 671 672 // interface ops 673 (ConstInterface) -> 674 (IMake 675 (ConstNil <config.fe.TypeBytePtr()>) 676 (ConstNil <config.fe.TypeBytePtr()>)) 677 678 (Check (NilCheck (GetG _) _) next) -> (Plain nil next) 679 680 (If (Not cond) yes no) -> (If cond no yes) 681 (If (ConstBool [c]) yes no) && c == 1 -> (First nil yes no) 682 (If (ConstBool [c]) yes no) && c == 0 -> (First nil no yes) 683 684 // Get rid of Convert ops for pointer arithmetic on unsafe.Pointer. 685 (Convert (Add64 (Convert ptr mem) off) mem) -> (Add64 ptr off) 686 (Convert (Add64 off (Convert ptr mem)) mem) -> (Add64 ptr off) 687 (Convert (Convert ptr mem) mem) -> ptr 688 689 // Decompose compound argument values 690 (Arg {n} [off]) && v.Type.IsString() -> 691 (StringMake 692 (Arg <config.fe.TypeBytePtr()> {n} [off]) 693 (Arg <config.fe.TypeInt()> {n} [off+config.PtrSize])) 694 695 (Arg {n} [off]) && v.Type.IsSlice() -> 696 (SliceMake 697 (Arg <v.Type.ElemType().PtrTo()> {n} [off]) 698 (Arg <config.fe.TypeInt()> {n} [off+config.PtrSize]) 699 (Arg <config.fe.TypeInt()> {n} [off+2*config.PtrSize])) 700 701 (Arg {n} [off]) && v.Type.IsInterface() -> 702 (IMake 703 (Arg <config.fe.TypeBytePtr()> {n} [off]) 704 (Arg <config.fe.TypeBytePtr()> {n} [off+config.PtrSize])) 705 706 (Arg {n} [off]) && v.Type.IsComplex() && v.Type.Size() == 16 -> 707 (ComplexMake 708 (Arg <config.fe.TypeFloat64()> {n} [off]) 709 (Arg <config.fe.TypeFloat64()> {n} [off+8])) 710 711 (Arg {n} [off]) && v.Type.IsComplex() && v.Type.Size() == 8 -> 712 (ComplexMake 713 (Arg <config.fe.TypeFloat32()> {n} [off]) 714 (Arg <config.fe.TypeFloat32()> {n} [off+4])) 715 716 (Arg <t>) && t.IsStruct() && t.NumFields() == 0 && config.fe.CanSSA(t) -> 717 (StructMake0) 718 (Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 1 && config.fe.CanSSA(t) -> 719 (StructMake1 720 (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)])) 721 (Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 2 && config.fe.CanSSA(t) -> 722 (StructMake2 723 (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)]) 724 (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)])) 725 (Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 3 && config.fe.CanSSA(t) -> 726 (StructMake3 727 (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)]) 728 (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)]) 729 (Arg <t.FieldType(2)> {n} [off+t.FieldOff(2)])) 730 (Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 4 && config.fe.CanSSA(t) -> 731 (StructMake4 732 (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)]) 733 (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)]) 734 (Arg <t.FieldType(2)> {n} [off+t.FieldOff(2)]) 735 (Arg <t.FieldType(3)> {n} [off+t.FieldOff(3)])) 736 737 // strength reduction of divide by a constant. 738 // Note: frontend does <=32 bits. We only need to do 64 bits here. 739 // TODO: Do them all here? 740 741 // Div/mod by 1. Currently handled by frontend. 742 //(Div64 n (Const64 [1])) -> n 743 //(Div64u n (Const64 [1])) -> n 744 //(Mod64 n (Const64 [1])) -> (Const64 [0]) 745 //(Mod64u n (Const64 [1])) -> (Const64 [0]) 746 747 // Unsigned divide by power of 2. 748 (Div64u <t> n (Const64 [c])) && isPowerOfTwo(c) -> (Rsh64Ux64 n (Const64 <t> [log2(c)])) 749 (Mod64u <t> n (Const64 [c])) && isPowerOfTwo(c) -> (And64 n (Const64 <t> [c-1])) 750 751 // Signed divide by power of 2. Currently handled by frontend. 752 // n / c = n >> log(c) if n >= 0 753 // = (n+c-1) >> log(c) if n < 0 754 // We conditionally add c-1 by adding n>>63>>(64-log(c)) (first shift signed, second shift unsigned). 755 //(Div64 <t> n (Const64 [c])) && isPowerOfTwo(c) -> 756 // (Rsh64x64 757 // (Add64 <t> 758 // n 759 // (Rsh64Ux64 <t> 760 // (Rsh64x64 <t> n (Const64 <t> [63])) 761 // (Const64 <t> [64-log2(c)]))) 762 // (Const64 <t> [log2(c)])) 763 764 // Unsigned divide, not a power of 2. Strength reduce to a multiply. 765 (Div64u <t> x (Const64 [c])) && umagic64ok(c) && !umagic64a(c) -> 766 (Rsh64Ux64 767 (Hmul64u <t> 768 (Const64 <t> [umagic64m(c)]) 769 x) 770 (Const64 <t> [umagic64s(c)])) 771 (Div64u <t> x (Const64 [c])) && umagic64ok(c) && umagic64a(c) -> 772 (Rsh64Ux64 773 (Avg64u <t> 774 (Hmul64u <t> 775 x 776 (Const64 <t> [umagic64m(c)])) 777 x) 778 (Const64 <t> [umagic64s(c)-1])) 779 780 // Signed divide, not a power of 2. Strength reduce to a multiply. 781 (Div64 <t> x (Const64 [c])) && c > 0 && smagic64ok(c) && smagic64m(c) > 0 -> 782 (Sub64 <t> 783 (Rsh64x64 <t> 784 (Hmul64 <t> 785 (Const64 <t> [smagic64m(c)]) 786 x) 787 (Const64 <t> [smagic64s(c)])) 788 (Rsh64x64 <t> 789 x 790 (Const64 <t> [63]))) 791 (Div64 <t> x (Const64 [c])) && c > 0 && smagic64ok(c) && smagic64m(c) < 0 -> 792 (Sub64 <t> 793 (Rsh64x64 <t> 794 (Add64 <t> 795 (Hmul64 <t> 796 (Const64 <t> [smagic64m(c)]) 797 x) 798 x) 799 (Const64 <t> [smagic64s(c)])) 800 (Rsh64x64 <t> 801 x 802 (Const64 <t> [63]))) 803 (Div64 <t> x (Const64 [c])) && c < 0 && smagic64ok(c) && smagic64m(c) > 0 -> 804 (Neg64 <t> 805 (Sub64 <t> 806 (Rsh64x64 <t> 807 (Hmul64 <t> 808 (Const64 <t> [smagic64m(c)]) 809 x) 810 (Const64 <t> [smagic64s(c)])) 811 (Rsh64x64 <t> 812 x 813 (Const64 <t> [63])))) 814 (Div64 <t> x (Const64 [c])) && c < 0 && smagic64ok(c) && smagic64m(c) < 0 -> 815 (Neg64 <t> 816 (Sub64 <t> 817 (Rsh64x64 <t> 818 (Add64 <t> 819 (Hmul64 <t> 820 (Const64 <t> [smagic64m(c)]) 821 x) 822 x) 823 (Const64 <t> [smagic64s(c)])) 824 (Rsh64x64 <t> 825 x 826 (Const64 <t> [63])))) 827 828 // A%B = A-(A/B*B). 829 // This implements % with two * and a bunch of ancillary ops. 830 // One of the * is free if the user's code also computes A/B. 831 (Mod64 <t> x (Const64 [c])) && x.Op != OpConst64 && smagic64ok(c) 832 -> (Sub64 x (Mul64 <t> (Div64 <t> x (Const64 <t> [c])) (Const64 <t> [c]))) 833 (Mod64u <t> x (Const64 [c])) && x.Op != OpConst64 && umagic64ok(c) 834 -> (Sub64 x (Mul64 <t> (Div64u <t> x (Const64 <t> [c])) (Const64 <t> [c])))