github.com/eun/go@v0.0.0-20170811110501-92cfd07a6cfd/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 // Simplifications that apply to all backend architectures. As an example, this 6 // Go source code 7 // 8 // y := 0 * x 9 // 10 // can be translated into y := 0 without losing any information, which saves a 11 // pointless multiplication instruction. Other .rules files in this directory 12 // (for example AMD64.rules) contain rules specific to the architecture in the 13 // filename. The rules here apply to every architecture. 14 // 15 // The code for parsing this file lives in rulegen.go; this file generates 16 // ssa/rewritegeneric.go. 17 18 // values are specified using the following format: 19 // (op <type> [auxint] {aux} arg0 arg1 ...) 20 // the type, aux, and auxint fields are optional 21 // on the matching side 22 // - the type, aux, and auxint fields must match if they are specified. 23 // - the first occurrence of a variable defines that variable. Subsequent 24 // uses must match (be == to) the first use. 25 // - v is defined to be the value matched. 26 // - an additional conditional can be provided after the match pattern with "&&". 27 // on the generated side 28 // - the type of the top-level expression is the same as the one on the left-hand side. 29 // - the type of any subexpressions must be specified explicitly (or 30 // be specified in the op's type field). 31 // - auxint will be 0 if not specified. 32 // - aux will be nil if not specified. 33 34 // blocks are specified using the following format: 35 // (kind controlvalue succ0 succ1 ...) 36 // controlvalue must be "nil" or a value expression 37 // succ* fields must be variables 38 // For now, the generated successors must be a permutation of the matched successors. 39 40 // constant folding 41 (Trunc16to8 (Const16 [c])) -> (Const8 [int64(int8(c))]) 42 (Trunc32to8 (Const32 [c])) -> (Const8 [int64(int8(c))]) 43 (Trunc32to16 (Const32 [c])) -> (Const16 [int64(int16(c))]) 44 (Trunc64to8 (Const64 [c])) -> (Const8 [int64(int8(c))]) 45 (Trunc64to16 (Const64 [c])) -> (Const16 [int64(int16(c))]) 46 (Trunc64to32 (Const64 [c])) -> (Const32 [int64(int32(c))]) 47 (Cvt64Fto32F (Const64F [c])) -> (Const32F [f2i(float64(i2f32(c)))]) 48 (Cvt32Fto64F (Const32F [c])) -> (Const64F [c]) // c is already a 64 bit float 49 (Round32F x:(Const32F)) -> x 50 (Round64F x:(Const64F)) -> x 51 52 (Trunc16to8 (ZeroExt8to16 x)) -> x 53 (Trunc32to8 (ZeroExt8to32 x)) -> x 54 (Trunc32to16 (ZeroExt8to32 x)) -> (ZeroExt8to16 x) 55 (Trunc32to16 (ZeroExt16to32 x)) -> x 56 (Trunc64to8 (ZeroExt8to64 x)) -> x 57 (Trunc64to16 (ZeroExt8to64 x)) -> (ZeroExt8to16 x) 58 (Trunc64to16 (ZeroExt16to64 x)) -> x 59 (Trunc64to32 (ZeroExt8to64 x)) -> (ZeroExt8to32 x) 60 (Trunc64to32 (ZeroExt16to64 x)) -> (ZeroExt16to32 x) 61 (Trunc64to32 (ZeroExt32to64 x)) -> x 62 (Trunc16to8 (SignExt8to16 x)) -> x 63 (Trunc32to8 (SignExt8to32 x)) -> x 64 (Trunc32to16 (SignExt8to32 x)) -> (SignExt8to16 x) 65 (Trunc32to16 (SignExt16to32 x)) -> x 66 (Trunc64to8 (SignExt8to64 x)) -> x 67 (Trunc64to16 (SignExt8to64 x)) -> (SignExt8to16 x) 68 (Trunc64to16 (SignExt16to64 x)) -> x 69 (Trunc64to32 (SignExt8to64 x)) -> (SignExt8to32 x) 70 (Trunc64to32 (SignExt16to64 x)) -> (SignExt16to32 x) 71 (Trunc64to32 (SignExt32to64 x)) -> x 72 73 (ZeroExt8to16 (Const8 [c])) -> (Const16 [int64( uint8(c))]) 74 (ZeroExt8to32 (Const8 [c])) -> (Const32 [int64( uint8(c))]) 75 (ZeroExt8to64 (Const8 [c])) -> (Const64 [int64( uint8(c))]) 76 (ZeroExt16to32 (Const16 [c])) -> (Const32 [int64(uint16(c))]) 77 (ZeroExt16to64 (Const16 [c])) -> (Const64 [int64(uint16(c))]) 78 (ZeroExt32to64 (Const32 [c])) -> (Const64 [int64(uint32(c))]) 79 (SignExt8to16 (Const8 [c])) -> (Const16 [int64( int8(c))]) 80 (SignExt8to32 (Const8 [c])) -> (Const32 [int64( int8(c))]) 81 (SignExt8to64 (Const8 [c])) -> (Const64 [int64( int8(c))]) 82 (SignExt16to32 (Const16 [c])) -> (Const32 [int64( int16(c))]) 83 (SignExt16to64 (Const16 [c])) -> (Const64 [int64( int16(c))]) 84 (SignExt32to64 (Const32 [c])) -> (Const64 [int64( int32(c))]) 85 86 (Neg8 (Const8 [c])) -> (Const8 [int64( -int8(c))]) 87 (Neg16 (Const16 [c])) -> (Const16 [int64(-int16(c))]) 88 (Neg32 (Const32 [c])) -> (Const32 [int64(-int32(c))]) 89 (Neg64 (Const64 [c])) -> (Const64 [-c]) 90 (Neg32F (Const32F [c])) && i2f(c) != 0 -> (Const32F [f2i(-i2f(c))]) 91 (Neg64F (Const64F [c])) && i2f(c) != 0 -> (Const64F [f2i(-i2f(c))]) 92 93 (Add8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c+d))]) 94 (Add16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c+d))]) 95 (Add32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c+d))]) 96 (Add64 (Const64 [c]) (Const64 [d])) -> (Const64 [c+d]) 97 (Add32F (Const32F [c]) (Const32F [d])) -> 98 (Const32F [f2i(float64(i2f32(c) + i2f32(d)))]) // ensure we combine the operands with 32 bit precision 99 (Add64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) + i2f(d))]) 100 (AddPtr <t> x (Const64 [c])) -> (OffPtr <t> x [c]) 101 (AddPtr <t> x (Const32 [c])) -> (OffPtr <t> x [c]) 102 103 (Sub8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c-d))]) 104 (Sub16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c-d))]) 105 (Sub32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c-d))]) 106 (Sub64 (Const64 [c]) (Const64 [d])) -> (Const64 [c-d]) 107 (Sub32F (Const32F [c]) (Const32F [d])) -> 108 (Const32F [f2i(float64(i2f32(c) - i2f32(d)))]) 109 (Sub64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) - i2f(d))]) 110 111 (Mul8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c*d))]) 112 (Mul16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c*d))]) 113 (Mul32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c*d))]) 114 (Mul64 (Const64 [c]) (Const64 [d])) -> (Const64 [c*d]) 115 (Mul32F (Const32F [c]) (Const32F [d])) -> 116 (Const32F [f2i(float64(i2f32(c) * i2f32(d)))]) 117 (Mul64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) * i2f(d))]) 118 119 (And8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c&d))]) 120 (And16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c&d))]) 121 (And32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c&d))]) 122 (And64 (Const64 [c]) (Const64 [d])) -> (Const64 [c&d]) 123 124 (Or8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c|d))]) 125 (Or16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c|d))]) 126 (Or32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c|d))]) 127 (Or64 (Const64 [c]) (Const64 [d])) -> (Const64 [c|d]) 128 129 (Xor8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c^d))]) 130 (Xor16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c^d))]) 131 (Xor32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c^d))]) 132 (Xor64 (Const64 [c]) (Const64 [d])) -> (Const64 [c^d]) 133 134 (Div8 (Const8 [c]) (Const8 [d])) && d != 0 -> (Const8 [int64(int8(c)/int8(d))]) 135 (Div16 (Const16 [c]) (Const16 [d])) && d != 0 -> (Const16 [int64(int16(c)/int16(d))]) 136 (Div32 (Const32 [c]) (Const32 [d])) && d != 0 -> (Const32 [int64(int32(c)/int32(d))]) 137 (Div64 (Const64 [c]) (Const64 [d])) && d != 0 -> (Const64 [c/d]) 138 (Div8u (Const8 [c]) (Const8 [d])) && d != 0 -> (Const8 [int64(int8(uint8(c)/uint8(d)))]) 139 (Div16u (Const16 [c]) (Const16 [d])) && d != 0 -> (Const16 [int64(int16(uint16(c)/uint16(d)))]) 140 (Div32u (Const32 [c]) (Const32 [d])) && d != 0 -> (Const32 [int64(int32(uint32(c)/uint32(d)))]) 141 (Div64u (Const64 [c]) (Const64 [d])) && d != 0 -> (Const64 [int64(uint64(c)/uint64(d))]) 142 (Div32F (Const32F [c]) (Const32F [d])) -> (Const32F [f2i(float64(i2f32(c) / i2f32(d)))]) 143 (Div64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) / i2f(d))]) 144 145 // Convert x * 1 to x. 146 (Mul8 (Const8 [1]) x) -> x 147 (Mul16 (Const16 [1]) x) -> x 148 (Mul32 (Const32 [1]) x) -> x 149 (Mul64 (Const64 [1]) x) -> x 150 151 // Convert x * -1 to -x. 152 (Mul8 (Const8 [-1]) x) -> (Neg8 x) 153 (Mul16 (Const16 [-1]) x) -> (Neg16 x) 154 (Mul32 (Const32 [-1]) x) -> (Neg32 x) 155 (Mul64 (Const64 [-1]) x) -> (Neg64 x) 156 157 // Convert multiplication by a power of two to a shift. 158 (Mul8 <t> n (Const8 [c])) && isPowerOfTwo(c) -> (Lsh8x64 <t> n (Const64 <typ.UInt64> [log2(c)])) 159 (Mul16 <t> n (Const16 [c])) && isPowerOfTwo(c) -> (Lsh16x64 <t> n (Const64 <typ.UInt64> [log2(c)])) 160 (Mul32 <t> n (Const32 [c])) && isPowerOfTwo(c) -> (Lsh32x64 <t> n (Const64 <typ.UInt64> [log2(c)])) 161 (Mul64 <t> n (Const64 [c])) && isPowerOfTwo(c) -> (Lsh64x64 <t> n (Const64 <typ.UInt64> [log2(c)])) 162 (Mul8 <t> n (Const8 [c])) && t.IsSigned() && isPowerOfTwo(-c) -> (Neg8 (Lsh8x64 <t> n (Const64 <typ.UInt64> [log2(-c)]))) 163 (Mul16 <t> n (Const16 [c])) && t.IsSigned() && isPowerOfTwo(-c) -> (Neg16 (Lsh16x64 <t> n (Const64 <typ.UInt64> [log2(-c)]))) 164 (Mul32 <t> n (Const32 [c])) && t.IsSigned() && isPowerOfTwo(-c) -> (Neg32 (Lsh32x64 <t> n (Const64 <typ.UInt64> [log2(-c)]))) 165 (Mul64 <t> n (Const64 [c])) && t.IsSigned() && isPowerOfTwo(-c) -> (Neg64 (Lsh64x64 <t> n (Const64 <typ.UInt64> [log2(-c)]))) 166 167 (Mod8 (Const8 [c]) (Const8 [d])) && d != 0 -> (Const8 [int64(int8(c % d))]) 168 (Mod16 (Const16 [c]) (Const16 [d])) && d != 0 -> (Const16 [int64(int16(c % d))]) 169 (Mod32 (Const32 [c]) (Const32 [d])) && d != 0 -> (Const32 [int64(int32(c % d))]) 170 (Mod64 (Const64 [c]) (Const64 [d])) && d != 0 -> (Const64 [c % d]) 171 172 (Mod8u (Const8 [c]) (Const8 [d])) && d != 0 -> (Const8 [int64(uint8(c) % uint8(d))]) 173 (Mod16u (Const16 [c]) (Const16 [d])) && d != 0 -> (Const16 [int64(uint16(c) % uint16(d))]) 174 (Mod32u (Const32 [c]) (Const32 [d])) && d != 0 -> (Const32 [int64(uint32(c) % uint32(d))]) 175 (Mod64u (Const64 [c]) (Const64 [d])) && d != 0 -> (Const64 [int64(uint64(c) % uint64(d))]) 176 177 (Lsh64x64 (Const64 [c]) (Const64 [d])) -> (Const64 [c << uint64(d)]) 178 (Rsh64x64 (Const64 [c]) (Const64 [d])) -> (Const64 [c >> uint64(d)]) 179 (Rsh64Ux64 (Const64 [c]) (Const64 [d])) -> (Const64 [int64(uint64(c) >> uint64(d))]) 180 (Lsh32x64 (Const32 [c]) (Const64 [d])) -> (Const32 [int64(int32(c) << uint64(d))]) 181 (Rsh32x64 (Const32 [c]) (Const64 [d])) -> (Const32 [int64(int32(c) >> uint64(d))]) 182 (Rsh32Ux64 (Const32 [c]) (Const64 [d])) -> (Const32 [int64(int32(uint32(c) >> uint64(d)))]) 183 (Lsh16x64 (Const16 [c]) (Const64 [d])) -> (Const16 [int64(int16(c) << uint64(d))]) 184 (Rsh16x64 (Const16 [c]) (Const64 [d])) -> (Const16 [int64(int16(c) >> uint64(d))]) 185 (Rsh16Ux64 (Const16 [c]) (Const64 [d])) -> (Const16 [int64(int16(uint16(c) >> uint64(d)))]) 186 (Lsh8x64 (Const8 [c]) (Const64 [d])) -> (Const8 [int64(int8(c) << uint64(d))]) 187 (Rsh8x64 (Const8 [c]) (Const64 [d])) -> (Const8 [int64(int8(c) >> uint64(d))]) 188 (Rsh8Ux64 (Const8 [c]) (Const64 [d])) -> (Const8 [int64(int8(uint8(c) >> uint64(d)))]) 189 190 // Fold IsInBounds when the range of the index cannot exceed the limit. 191 (IsInBounds (ZeroExt8to32 _) (Const32 [c])) && (1 << 8) <= c -> (ConstBool [1]) 192 (IsInBounds (ZeroExt8to64 _) (Const64 [c])) && (1 << 8) <= c -> (ConstBool [1]) 193 (IsInBounds (ZeroExt16to32 _) (Const32 [c])) && (1 << 16) <= c -> (ConstBool [1]) 194 (IsInBounds (ZeroExt16to64 _) (Const64 [c])) && (1 << 16) <= c -> (ConstBool [1]) 195 (IsInBounds x x) -> (ConstBool [0]) 196 (IsInBounds (And8 (Const8 [c]) _) (Const8 [d])) && 0 <= c && c < d -> (ConstBool [1]) 197 (IsInBounds (ZeroExt8to16 (And8 (Const8 [c]) _)) (Const16 [d])) && 0 <= c && c < d -> (ConstBool [1]) 198 (IsInBounds (ZeroExt8to32 (And8 (Const8 [c]) _)) (Const32 [d])) && 0 <= c && c < d -> (ConstBool [1]) 199 (IsInBounds (ZeroExt8to64 (And8 (Const8 [c]) _)) (Const64 [d])) && 0 <= c && c < d -> (ConstBool [1]) 200 (IsInBounds (And16 (Const16 [c]) _) (Const16 [d])) && 0 <= c && c < d -> (ConstBool [1]) 201 (IsInBounds (ZeroExt16to32 (And16 (Const16 [c]) _)) (Const32 [d])) && 0 <= c && c < d -> (ConstBool [1]) 202 (IsInBounds (ZeroExt16to64 (And16 (Const16 [c]) _)) (Const64 [d])) && 0 <= c && c < d -> (ConstBool [1]) 203 (IsInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c < d -> (ConstBool [1]) 204 (IsInBounds (ZeroExt32to64 (And32 (Const32 [c]) _)) (Const64 [d])) && 0 <= c && c < d -> (ConstBool [1]) 205 (IsInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c < d -> (ConstBool [1]) 206 (IsInBounds (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(0 <= c && c < d)]) 207 (IsInBounds (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(0 <= c && c < d)]) 208 // (Mod64u x y) is always between 0 (inclusive) and y (exclusive). 209 (IsInBounds (Mod32u _ y) y) -> (ConstBool [1]) 210 (IsInBounds (Mod64u _ y) y) -> (ConstBool [1]) 211 // Right shifting a unsigned number limits its value. 212 (IsInBounds (ZeroExt8to64 (Rsh8Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d -> (ConstBool [1]) 213 (IsInBounds (ZeroExt8to32 (Rsh8Ux64 _ (Const64 [c]))) (Const32 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d -> (ConstBool [1]) 214 (IsInBounds (ZeroExt8to16 (Rsh8Ux64 _ (Const64 [c]))) (Const16 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d -> (ConstBool [1]) 215 (IsInBounds (Rsh8Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d -> (ConstBool [1]) 216 (IsInBounds (ZeroExt16to64 (Rsh16Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d -> (ConstBool [1]) 217 (IsInBounds (ZeroExt16to32 (Rsh16Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d -> (ConstBool [1]) 218 (IsInBounds (Rsh16Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d -> (ConstBool [1]) 219 (IsInBounds (ZeroExt32to64 (Rsh32Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 32 && 1<<uint(32-c)-1 < d -> (ConstBool [1]) 220 (IsInBounds (Rsh32Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 32 && 1<<uint(32-c)-1 < d -> (ConstBool [1]) 221 (IsInBounds (Rsh64Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 64 && 1<<uint(64-c)-1 < d -> (ConstBool [1]) 222 223 (IsSliceInBounds x x) -> (ConstBool [1]) 224 (IsSliceInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c <= d -> (ConstBool [1]) 225 (IsSliceInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c <= d -> (ConstBool [1]) 226 (IsSliceInBounds (Const32 [0]) _) -> (ConstBool [1]) 227 (IsSliceInBounds (Const64 [0]) _) -> (ConstBool [1]) 228 (IsSliceInBounds (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(0 <= c && c <= d)]) 229 (IsSliceInBounds (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(0 <= c && c <= d)]) 230 (IsSliceInBounds (SliceLen x) (SliceCap x)) -> (ConstBool [1]) 231 232 (Eq64 x x) -> (ConstBool [1]) 233 (Eq32 x x) -> (ConstBool [1]) 234 (Eq16 x x) -> (ConstBool [1]) 235 (Eq8 x x) -> (ConstBool [1]) 236 (EqB (ConstBool [c]) (ConstBool [d])) -> (ConstBool [b2i(c == d)]) 237 (EqB (ConstBool [0]) x) -> (Not x) 238 (EqB (ConstBool [1]) x) -> x 239 240 (Neq64 x x) -> (ConstBool [0]) 241 (Neq32 x x) -> (ConstBool [0]) 242 (Neq16 x x) -> (ConstBool [0]) 243 (Neq8 x x) -> (ConstBool [0]) 244 (NeqB (ConstBool [c]) (ConstBool [d])) -> (ConstBool [b2i(c != d)]) 245 (NeqB (ConstBool [0]) x) -> x 246 (NeqB (ConstBool [1]) x) -> (Not x) 247 (NeqB (Not x) (Not y)) -> (NeqB x y) 248 249 (Eq64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) -> (Eq64 (Const64 <t> [c-d]) x) 250 (Eq32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) -> (Eq32 (Const32 <t> [int64(int32(c-d))]) x) 251 (Eq16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) -> (Eq16 (Const16 <t> [int64(int16(c-d))]) x) 252 (Eq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) -> (Eq8 (Const8 <t> [int64(int8(c-d))]) x) 253 254 (Neq64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) -> (Neq64 (Const64 <t> [c-d]) x) 255 (Neq32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) -> (Neq32 (Const32 <t> [int64(int32(c-d))]) x) 256 (Neq16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) -> (Neq16 (Const16 <t> [int64(int16(c-d))]) x) 257 (Neq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) -> (Neq8 (Const8 <t> [int64(int8(c-d))]) x) 258 259 // Canonicalize x-const to x+(-const) 260 (Sub64 x (Const64 <t> [c])) && x.Op != OpConst64 -> (Add64 (Const64 <t> [-c]) x) 261 (Sub32 x (Const32 <t> [c])) && x.Op != OpConst32 -> (Add32 (Const32 <t> [int64(int32(-c))]) x) 262 (Sub16 x (Const16 <t> [c])) && x.Op != OpConst16 -> (Add16 (Const16 <t> [int64(int16(-c))]) x) 263 (Sub8 x (Const8 <t> [c])) && x.Op != OpConst8 -> (Add8 (Const8 <t> [int64(int8(-c))]) x) 264 265 // fold negation into comparison operators 266 (Not (Eq64 x y)) -> (Neq64 x y) 267 (Not (Eq32 x y)) -> (Neq32 x y) 268 (Not (Eq16 x y)) -> (Neq16 x y) 269 (Not (Eq8 x y)) -> (Neq8 x y) 270 (Not (EqB x y)) -> (NeqB x y) 271 272 (Not (Neq64 x y)) -> (Eq64 x y) 273 (Not (Neq32 x y)) -> (Eq32 x y) 274 (Not (Neq16 x y)) -> (Eq16 x y) 275 (Not (Neq8 x y)) -> (Eq8 x y) 276 (Not (NeqB x y)) -> (EqB x y) 277 278 (Not (Greater64 x y)) -> (Leq64 x y) 279 (Not (Greater32 x y)) -> (Leq32 x y) 280 (Not (Greater16 x y)) -> (Leq16 x y) 281 (Not (Greater8 x y)) -> (Leq8 x y) 282 283 (Not (Greater64U x y)) -> (Leq64U x y) 284 (Not (Greater32U x y)) -> (Leq32U x y) 285 (Not (Greater16U x y)) -> (Leq16U x y) 286 (Not (Greater8U x y)) -> (Leq8U x y) 287 288 (Not (Geq64 x y)) -> (Less64 x y) 289 (Not (Geq32 x y)) -> (Less32 x y) 290 (Not (Geq16 x y)) -> (Less16 x y) 291 (Not (Geq8 x y)) -> (Less8 x y) 292 293 (Not (Geq64U x y)) -> (Less64U x y) 294 (Not (Geq32U x y)) -> (Less32U x y) 295 (Not (Geq16U x y)) -> (Less16U x y) 296 (Not (Geq8U x y)) -> (Less8U x y) 297 298 (Not (Less64 x y)) -> (Geq64 x y) 299 (Not (Less32 x y)) -> (Geq32 x y) 300 (Not (Less16 x y)) -> (Geq16 x y) 301 (Not (Less8 x y)) -> (Geq8 x y) 302 303 (Not (Less64U x y)) -> (Geq64U x y) 304 (Not (Less32U x y)) -> (Geq32U x y) 305 (Not (Less16U x y)) -> (Geq16U x y) 306 (Not (Less8U x y)) -> (Geq8U x y) 307 308 (Not (Leq64 x y)) -> (Greater64 x y) 309 (Not (Leq32 x y)) -> (Greater32 x y) 310 (Not (Leq16 x y)) -> (Greater16 x y) 311 (Not (Leq8 x y)) -> (Greater8 x y) 312 313 (Not (Leq64U x y)) -> (Greater64U x y) 314 (Not (Leq32U x y)) -> (Greater32U x y) 315 (Not (Leq16U x y)) -> (Greater16U x y) 316 (Not (Leq8U x y)) -> (Greater8U x y) 317 318 // Distribute multiplication c * (d+x) -> c*d + c*x. Useful for: 319 // a[i].b = ...; a[i+1].b = ... 320 (Mul64 (Const64 <t> [c]) (Add64 <t> (Const64 <t> [d]) x)) -> 321 (Add64 (Const64 <t> [c*d]) (Mul64 <t> (Const64 <t> [c]) x)) 322 (Mul32 (Const32 <t> [c]) (Add32 <t> (Const32 <t> [d]) x)) -> 323 (Add32 (Const32 <t> [int64(int32(c*d))]) (Mul32 <t> (Const32 <t> [c]) x)) 324 325 // rewrite shifts of 8/16/32 bit consts into 64 bit consts to reduce 326 // the number of the other rewrite rules for const shifts 327 (Lsh64x32 <t> x (Const32 [c])) -> (Lsh64x64 x (Const64 <t> [int64(uint32(c))])) 328 (Lsh64x16 <t> x (Const16 [c])) -> (Lsh64x64 x (Const64 <t> [int64(uint16(c))])) 329 (Lsh64x8 <t> x (Const8 [c])) -> (Lsh64x64 x (Const64 <t> [int64(uint8(c))])) 330 (Rsh64x32 <t> x (Const32 [c])) -> (Rsh64x64 x (Const64 <t> [int64(uint32(c))])) 331 (Rsh64x16 <t> x (Const16 [c])) -> (Rsh64x64 x (Const64 <t> [int64(uint16(c))])) 332 (Rsh64x8 <t> x (Const8 [c])) -> (Rsh64x64 x (Const64 <t> [int64(uint8(c))])) 333 (Rsh64Ux32 <t> x (Const32 [c])) -> (Rsh64Ux64 x (Const64 <t> [int64(uint32(c))])) 334 (Rsh64Ux16 <t> x (Const16 [c])) -> (Rsh64Ux64 x (Const64 <t> [int64(uint16(c))])) 335 (Rsh64Ux8 <t> x (Const8 [c])) -> (Rsh64Ux64 x (Const64 <t> [int64(uint8(c))])) 336 337 (Lsh32x32 <t> x (Const32 [c])) -> (Lsh32x64 x (Const64 <t> [int64(uint32(c))])) 338 (Lsh32x16 <t> x (Const16 [c])) -> (Lsh32x64 x (Const64 <t> [int64(uint16(c))])) 339 (Lsh32x8 <t> x (Const8 [c])) -> (Lsh32x64 x (Const64 <t> [int64(uint8(c))])) 340 (Rsh32x32 <t> x (Const32 [c])) -> (Rsh32x64 x (Const64 <t> [int64(uint32(c))])) 341 (Rsh32x16 <t> x (Const16 [c])) -> (Rsh32x64 x (Const64 <t> [int64(uint16(c))])) 342 (Rsh32x8 <t> x (Const8 [c])) -> (Rsh32x64 x (Const64 <t> [int64(uint8(c))])) 343 (Rsh32Ux32 <t> x (Const32 [c])) -> (Rsh32Ux64 x (Const64 <t> [int64(uint32(c))])) 344 (Rsh32Ux16 <t> x (Const16 [c])) -> (Rsh32Ux64 x (Const64 <t> [int64(uint16(c))])) 345 (Rsh32Ux8 <t> x (Const8 [c])) -> (Rsh32Ux64 x (Const64 <t> [int64(uint8(c))])) 346 347 (Lsh16x32 <t> x (Const32 [c])) -> (Lsh16x64 x (Const64 <t> [int64(uint32(c))])) 348 (Lsh16x16 <t> x (Const16 [c])) -> (Lsh16x64 x (Const64 <t> [int64(uint16(c))])) 349 (Lsh16x8 <t> x (Const8 [c])) -> (Lsh16x64 x (Const64 <t> [int64(uint8(c))])) 350 (Rsh16x32 <t> x (Const32 [c])) -> (Rsh16x64 x (Const64 <t> [int64(uint32(c))])) 351 (Rsh16x16 <t> x (Const16 [c])) -> (Rsh16x64 x (Const64 <t> [int64(uint16(c))])) 352 (Rsh16x8 <t> x (Const8 [c])) -> (Rsh16x64 x (Const64 <t> [int64(uint8(c))])) 353 (Rsh16Ux32 <t> x (Const32 [c])) -> (Rsh16Ux64 x (Const64 <t> [int64(uint32(c))])) 354 (Rsh16Ux16 <t> x (Const16 [c])) -> (Rsh16Ux64 x (Const64 <t> [int64(uint16(c))])) 355 (Rsh16Ux8 <t> x (Const8 [c])) -> (Rsh16Ux64 x (Const64 <t> [int64(uint8(c))])) 356 357 (Lsh8x32 <t> x (Const32 [c])) -> (Lsh8x64 x (Const64 <t> [int64(uint32(c))])) 358 (Lsh8x16 <t> x (Const16 [c])) -> (Lsh8x64 x (Const64 <t> [int64(uint16(c))])) 359 (Lsh8x8 <t> x (Const8 [c])) -> (Lsh8x64 x (Const64 <t> [int64(uint8(c))])) 360 (Rsh8x32 <t> x (Const32 [c])) -> (Rsh8x64 x (Const64 <t> [int64(uint32(c))])) 361 (Rsh8x16 <t> x (Const16 [c])) -> (Rsh8x64 x (Const64 <t> [int64(uint16(c))])) 362 (Rsh8x8 <t> x (Const8 [c])) -> (Rsh8x64 x (Const64 <t> [int64(uint8(c))])) 363 (Rsh8Ux32 <t> x (Const32 [c])) -> (Rsh8Ux64 x (Const64 <t> [int64(uint32(c))])) 364 (Rsh8Ux16 <t> x (Const16 [c])) -> (Rsh8Ux64 x (Const64 <t> [int64(uint16(c))])) 365 (Rsh8Ux8 <t> x (Const8 [c])) -> (Rsh8Ux64 x (Const64 <t> [int64(uint8(c))])) 366 367 // shifts by zero 368 (Lsh64x64 x (Const64 [0])) -> x 369 (Rsh64x64 x (Const64 [0])) -> x 370 (Rsh64Ux64 x (Const64 [0])) -> x 371 (Lsh32x64 x (Const64 [0])) -> x 372 (Rsh32x64 x (Const64 [0])) -> x 373 (Rsh32Ux64 x (Const64 [0])) -> x 374 (Lsh16x64 x (Const64 [0])) -> x 375 (Rsh16x64 x (Const64 [0])) -> x 376 (Rsh16Ux64 x (Const64 [0])) -> x 377 (Lsh8x64 x (Const64 [0])) -> x 378 (Rsh8x64 x (Const64 [0])) -> x 379 (Rsh8Ux64 x (Const64 [0])) -> x 380 381 // zero shifted. 382 (Lsh64x64 (Const64 [0]) _) -> (Const64 [0]) 383 (Lsh64x32 (Const64 [0]) _) -> (Const64 [0]) 384 (Lsh64x16 (Const64 [0]) _) -> (Const64 [0]) 385 (Lsh64x8 (Const64 [0]) _) -> (Const64 [0]) 386 (Rsh64x64 (Const64 [0]) _) -> (Const64 [0]) 387 (Rsh64x32 (Const64 [0]) _) -> (Const64 [0]) 388 (Rsh64x16 (Const64 [0]) _) -> (Const64 [0]) 389 (Rsh64x8 (Const64 [0]) _) -> (Const64 [0]) 390 (Rsh64Ux64 (Const64 [0]) _) -> (Const64 [0]) 391 (Rsh64Ux32 (Const64 [0]) _) -> (Const64 [0]) 392 (Rsh64Ux16 (Const64 [0]) _) -> (Const64 [0]) 393 (Rsh64Ux8 (Const64 [0]) _) -> (Const64 [0]) 394 (Lsh32x64 (Const32 [0]) _) -> (Const32 [0]) 395 (Lsh32x32 (Const32 [0]) _) -> (Const32 [0]) 396 (Lsh32x16 (Const32 [0]) _) -> (Const32 [0]) 397 (Lsh32x8 (Const32 [0]) _) -> (Const32 [0]) 398 (Rsh32x64 (Const32 [0]) _) -> (Const32 [0]) 399 (Rsh32x32 (Const32 [0]) _) -> (Const32 [0]) 400 (Rsh32x16 (Const32 [0]) _) -> (Const32 [0]) 401 (Rsh32x8 (Const32 [0]) _) -> (Const32 [0]) 402 (Rsh32Ux64 (Const32 [0]) _) -> (Const32 [0]) 403 (Rsh32Ux32 (Const32 [0]) _) -> (Const32 [0]) 404 (Rsh32Ux16 (Const32 [0]) _) -> (Const32 [0]) 405 (Rsh32Ux8 (Const32 [0]) _) -> (Const32 [0]) 406 (Lsh16x64 (Const16 [0]) _) -> (Const16 [0]) 407 (Lsh16x32 (Const16 [0]) _) -> (Const16 [0]) 408 (Lsh16x16 (Const16 [0]) _) -> (Const16 [0]) 409 (Lsh16x8 (Const16 [0]) _) -> (Const16 [0]) 410 (Rsh16x64 (Const16 [0]) _) -> (Const16 [0]) 411 (Rsh16x32 (Const16 [0]) _) -> (Const16 [0]) 412 (Rsh16x16 (Const16 [0]) _) -> (Const16 [0]) 413 (Rsh16x8 (Const16 [0]) _) -> (Const16 [0]) 414 (Rsh16Ux64 (Const16 [0]) _) -> (Const16 [0]) 415 (Rsh16Ux32 (Const16 [0]) _) -> (Const16 [0]) 416 (Rsh16Ux16 (Const16 [0]) _) -> (Const16 [0]) 417 (Rsh16Ux8 (Const16 [0]) _) -> (Const16 [0]) 418 (Lsh8x64 (Const8 [0]) _) -> (Const8 [0]) 419 (Lsh8x32 (Const8 [0]) _) -> (Const8 [0]) 420 (Lsh8x16 (Const8 [0]) _) -> (Const8 [0]) 421 (Lsh8x8 (Const8 [0]) _) -> (Const8 [0]) 422 (Rsh8x64 (Const8 [0]) _) -> (Const8 [0]) 423 (Rsh8x32 (Const8 [0]) _) -> (Const8 [0]) 424 (Rsh8x16 (Const8 [0]) _) -> (Const8 [0]) 425 (Rsh8x8 (Const8 [0]) _) -> (Const8 [0]) 426 (Rsh8Ux64 (Const8 [0]) _) -> (Const8 [0]) 427 (Rsh8Ux32 (Const8 [0]) _) -> (Const8 [0]) 428 (Rsh8Ux16 (Const8 [0]) _) -> (Const8 [0]) 429 (Rsh8Ux8 (Const8 [0]) _) -> (Const8 [0]) 430 431 // large left shifts of all values, and right shifts of unsigned values 432 (Lsh64x64 _ (Const64 [c])) && uint64(c) >= 64 -> (Const64 [0]) 433 (Rsh64Ux64 _ (Const64 [c])) && uint64(c) >= 64 -> (Const64 [0]) 434 (Lsh32x64 _ (Const64 [c])) && uint64(c) >= 32 -> (Const32 [0]) 435 (Rsh32Ux64 _ (Const64 [c])) && uint64(c) >= 32 -> (Const32 [0]) 436 (Lsh16x64 _ (Const64 [c])) && uint64(c) >= 16 -> (Const16 [0]) 437 (Rsh16Ux64 _ (Const64 [c])) && uint64(c) >= 16 -> (Const16 [0]) 438 (Lsh8x64 _ (Const64 [c])) && uint64(c) >= 8 -> (Const8 [0]) 439 (Rsh8Ux64 _ (Const64 [c])) && uint64(c) >= 8 -> (Const8 [0]) 440 441 // combine const shifts 442 (Lsh64x64 <t> (Lsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Lsh64x64 x (Const64 <t> [c+d])) 443 (Lsh32x64 <t> (Lsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Lsh32x64 x (Const64 <t> [c+d])) 444 (Lsh16x64 <t> (Lsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Lsh16x64 x (Const64 <t> [c+d])) 445 (Lsh8x64 <t> (Lsh8x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Lsh8x64 x (Const64 <t> [c+d])) 446 447 (Rsh64x64 <t> (Rsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh64x64 x (Const64 <t> [c+d])) 448 (Rsh32x64 <t> (Rsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh32x64 x (Const64 <t> [c+d])) 449 (Rsh16x64 <t> (Rsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh16x64 x (Const64 <t> [c+d])) 450 (Rsh8x64 <t> (Rsh8x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh8x64 x (Const64 <t> [c+d])) 451 452 (Rsh64Ux64 <t> (Rsh64Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh64Ux64 x (Const64 <t> [c+d])) 453 (Rsh32Ux64 <t> (Rsh32Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh32Ux64 x (Const64 <t> [c+d])) 454 (Rsh16Ux64 <t> (Rsh16Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh16Ux64 x (Const64 <t> [c+d])) 455 (Rsh8Ux64 <t> (Rsh8Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) -> (Rsh8Ux64 x (Const64 <t> [c+d])) 456 457 // ((x >> c1) << c2) >> c3 458 (Rsh64Ux64 (Lsh64x64 (Rsh64Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 459 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 460 -> (Rsh64Ux64 x (Const64 <typ.UInt64> [c1-c2+c3])) 461 (Rsh32Ux64 (Lsh32x64 (Rsh32Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 462 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 463 -> (Rsh32Ux64 x (Const64 <typ.UInt64> [c1-c2+c3])) 464 (Rsh16Ux64 (Lsh16x64 (Rsh16Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 465 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 466 -> (Rsh16Ux64 x (Const64 <typ.UInt64> [c1-c2+c3])) 467 (Rsh8Ux64 (Lsh8x64 (Rsh8Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 468 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 469 -> (Rsh8Ux64 x (Const64 <typ.UInt64> [c1-c2+c3])) 470 471 // ((x << c1) >> c2) << c3 472 (Lsh64x64 (Rsh64Ux64 (Lsh64x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 473 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 474 -> (Lsh64x64 x (Const64 <typ.UInt64> [c1-c2+c3])) 475 (Lsh32x64 (Rsh32Ux64 (Lsh32x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 476 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 477 -> (Lsh32x64 x (Const64 <typ.UInt64> [c1-c2+c3])) 478 (Lsh16x64 (Rsh16Ux64 (Lsh16x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 479 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 480 -> (Lsh16x64 x (Const64 <typ.UInt64> [c1-c2+c3])) 481 (Lsh8x64 (Rsh8Ux64 (Lsh8x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3])) 482 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3) 483 -> (Lsh8x64 x (Const64 <typ.UInt64> [c1-c2+c3])) 484 485 // replace shifts with zero extensions 486 (Rsh16Ux64 (Lsh16x64 x (Const64 [8])) (Const64 [8])) -> (ZeroExt8to16 (Trunc16to8 <typ.UInt8> x)) 487 (Rsh32Ux64 (Lsh32x64 x (Const64 [24])) (Const64 [24])) -> (ZeroExt8to32 (Trunc32to8 <typ.UInt8> x)) 488 (Rsh64Ux64 (Lsh64x64 x (Const64 [56])) (Const64 [56])) -> (ZeroExt8to64 (Trunc64to8 <typ.UInt8> x)) 489 (Rsh32Ux64 (Lsh32x64 x (Const64 [16])) (Const64 [16])) -> (ZeroExt16to32 (Trunc32to16 <typ.UInt16> x)) 490 (Rsh64Ux64 (Lsh64x64 x (Const64 [48])) (Const64 [48])) -> (ZeroExt16to64 (Trunc64to16 <typ.UInt16> x)) 491 (Rsh64Ux64 (Lsh64x64 x (Const64 [32])) (Const64 [32])) -> (ZeroExt32to64 (Trunc64to32 <typ.UInt32> x)) 492 493 // replace shifts with sign extensions 494 (Rsh16x64 (Lsh16x64 x (Const64 [8])) (Const64 [8])) -> (SignExt8to16 (Trunc16to8 <typ.Int8> x)) 495 (Rsh32x64 (Lsh32x64 x (Const64 [24])) (Const64 [24])) -> (SignExt8to32 (Trunc32to8 <typ.Int8> x)) 496 (Rsh64x64 (Lsh64x64 x (Const64 [56])) (Const64 [56])) -> (SignExt8to64 (Trunc64to8 <typ.Int8> x)) 497 (Rsh32x64 (Lsh32x64 x (Const64 [16])) (Const64 [16])) -> (SignExt16to32 (Trunc32to16 <typ.Int16> x)) 498 (Rsh64x64 (Lsh64x64 x (Const64 [48])) (Const64 [48])) -> (SignExt16to64 (Trunc64to16 <typ.Int16> x)) 499 (Rsh64x64 (Lsh64x64 x (Const64 [32])) (Const64 [32])) -> (SignExt32to64 (Trunc64to32 <typ.Int32> x)) 500 501 // constant comparisons 502 (Eq64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c == d)]) 503 (Eq32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c == d)]) 504 (Eq16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c == d)]) 505 (Eq8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c == d)]) 506 507 (Neq64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c != d)]) 508 (Neq32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c != d)]) 509 (Neq16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c != d)]) 510 (Neq8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c != d)]) 511 512 (Greater64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c > d)]) 513 (Greater32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c > d)]) 514 (Greater16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c > d)]) 515 (Greater8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c > d)]) 516 517 (Greater64U (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(uint64(c) > uint64(d))]) 518 (Greater32U (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(uint32(c) > uint32(d))]) 519 (Greater16U (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(uint16(c) > uint16(d))]) 520 (Greater8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) > uint8(d))]) 521 522 (Geq64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c >= d)]) 523 (Geq32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c >= d)]) 524 (Geq16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c >= d)]) 525 (Geq8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c >= d)]) 526 527 (Geq64U (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(uint64(c) >= uint64(d))]) 528 (Geq32U (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(uint32(c) >= uint32(d))]) 529 (Geq16U (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(uint16(c) >= uint16(d))]) 530 (Geq8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) >= uint8(d))]) 531 532 (Less64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c < d)]) 533 (Less32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c < d)]) 534 (Less16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c < d)]) 535 (Less8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c < d)]) 536 537 (Less64U (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(uint64(c) < uint64(d))]) 538 (Less32U (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(uint32(c) < uint32(d))]) 539 (Less16U (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(uint16(c) < uint16(d))]) 540 (Less8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) < uint8(d))]) 541 542 (Leq64 (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(c <= d)]) 543 (Leq32 (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(c <= d)]) 544 (Leq16 (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(c <= d)]) 545 (Leq8 (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(c <= d)]) 546 547 (Leq64U (Const64 [c]) (Const64 [d])) -> (ConstBool [b2i(uint64(c) <= uint64(d))]) 548 (Leq32U (Const32 [c]) (Const32 [d])) -> (ConstBool [b2i(uint32(c) <= uint32(d))]) 549 (Leq16U (Const16 [c]) (Const16 [d])) -> (ConstBool [b2i(uint16(c) <= uint16(d))]) 550 (Leq8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) <= uint8(d))]) 551 552 // simplifications 553 (Or64 x x) -> x 554 (Or32 x x) -> x 555 (Or16 x x) -> x 556 (Or8 x x) -> x 557 (Or64 (Const64 [0]) x) -> x 558 (Or32 (Const32 [0]) x) -> x 559 (Or16 (Const16 [0]) x) -> x 560 (Or8 (Const8 [0]) x) -> x 561 (Or64 (Const64 [-1]) _) -> (Const64 [-1]) 562 (Or32 (Const32 [-1]) _) -> (Const32 [-1]) 563 (Or16 (Const16 [-1]) _) -> (Const16 [-1]) 564 (Or8 (Const8 [-1]) _) -> (Const8 [-1]) 565 (And64 x x) -> x 566 (And32 x x) -> x 567 (And16 x x) -> x 568 (And8 x x) -> x 569 (And64 (Const64 [-1]) x) -> x 570 (And32 (Const32 [-1]) x) -> x 571 (And16 (Const16 [-1]) x) -> x 572 (And8 (Const8 [-1]) x) -> x 573 (And64 (Const64 [0]) _) -> (Const64 [0]) 574 (And32 (Const32 [0]) _) -> (Const32 [0]) 575 (And16 (Const16 [0]) _) -> (Const16 [0]) 576 (And8 (Const8 [0]) _) -> (Const8 [0]) 577 (Xor64 x x) -> (Const64 [0]) 578 (Xor32 x x) -> (Const32 [0]) 579 (Xor16 x x) -> (Const16 [0]) 580 (Xor8 x x) -> (Const8 [0]) 581 (Xor64 (Const64 [0]) x) -> x 582 (Xor32 (Const32 [0]) x) -> x 583 (Xor16 (Const16 [0]) x) -> x 584 (Xor8 (Const8 [0]) x) -> x 585 (Add64 (Const64 [0]) x) -> x 586 (Add32 (Const32 [0]) x) -> x 587 (Add16 (Const16 [0]) x) -> x 588 (Add8 (Const8 [0]) x) -> x 589 (Sub64 x x) -> (Const64 [0]) 590 (Sub32 x x) -> (Const32 [0]) 591 (Sub16 x x) -> (Const16 [0]) 592 (Sub8 x x) -> (Const8 [0]) 593 (Mul64 (Const64 [0]) _) -> (Const64 [0]) 594 (Mul32 (Const32 [0]) _) -> (Const32 [0]) 595 (Mul16 (Const16 [0]) _) -> (Const16 [0]) 596 (Mul8 (Const8 [0]) _) -> (Const8 [0]) 597 (Com8 (Com8 x)) -> x 598 (Com16 (Com16 x)) -> x 599 (Com32 (Com32 x)) -> x 600 (Com64 (Com64 x)) -> x 601 (Com8 (Const8 [c])) -> (Const8 [^c]) 602 (Com16 (Const16 [c])) -> (Const16 [^c]) 603 (Com32 (Const32 [c])) -> (Const32 [^c]) 604 (Com64 (Const64 [c])) -> (Const64 [^c]) 605 (Neg8 (Sub8 x y)) -> (Sub8 y x) 606 (Neg16 (Sub16 x y)) -> (Sub16 y x) 607 (Neg32 (Sub32 x y)) -> (Sub32 y x) 608 (Neg64 (Sub64 x y)) -> (Sub64 y x) 609 (Add8 (Const8 [1]) (Com8 x)) -> (Neg8 x) 610 (Add16 (Const16 [1]) (Com16 x)) -> (Neg16 x) 611 (Add32 (Const32 [1]) (Com32 x)) -> (Neg32 x) 612 (Add64 (Const64 [1]) (Com64 x)) -> (Neg64 x) 613 614 (And64 x (And64 x y)) -> (And64 x y) 615 (And32 x (And32 x y)) -> (And32 x y) 616 (And16 x (And16 x y)) -> (And16 x y) 617 (And8 x (And8 x y)) -> (And8 x y) 618 (Or64 x (Or64 x y)) -> (Or64 x y) 619 (Or32 x (Or32 x y)) -> (Or32 x y) 620 (Or16 x (Or16 x y)) -> (Or16 x y) 621 (Or8 x (Or8 x y)) -> (Or8 x y) 622 (Xor64 x (Xor64 x y)) -> y 623 (Xor32 x (Xor32 x y)) -> y 624 (Xor16 x (Xor16 x y)) -> y 625 (Xor8 x (Xor8 x y)) -> y 626 627 // Ands clear bits. Ors set bits. 628 // If a subsequent Or will set all the bits 629 // that an And cleared, we can skip the And. 630 // This happens in bitmasking code like: 631 // x &^= 3 << shift // clear two old bits 632 // x |= v << shift // set two new bits 633 // when shift is a small constant and v ends up a constant 3. 634 (Or8 (And8 x (Const8 [c2])) (Const8 <t> [c1])) && ^(c1 | c2) == 0 -> (Or8 (Const8 <t> [c1]) x) 635 (Or16 (And16 x (Const16 [c2])) (Const16 <t> [c1])) && ^(c1 | c2) == 0 -> (Or16 (Const16 <t> [c1]) x) 636 (Or32 (And32 x (Const32 [c2])) (Const32 <t> [c1])) && ^(c1 | c2) == 0 -> (Or32 (Const32 <t> [c1]) x) 637 (Or64 (And64 x (Const64 [c2])) (Const64 <t> [c1])) && ^(c1 | c2) == 0 -> (Or64 (Const64 <t> [c1]) x) 638 639 (Trunc64to8 (And64 (Const64 [y]) x)) && y&0xFF == 0xFF -> (Trunc64to8 x) 640 (Trunc64to16 (And64 (Const64 [y]) x)) && y&0xFFFF == 0xFFFF -> (Trunc64to16 x) 641 (Trunc64to32 (And64 (Const64 [y]) x)) && y&0xFFFFFFFF == 0xFFFFFFFF -> (Trunc64to32 x) 642 (Trunc32to8 (And32 (Const32 [y]) x)) && y&0xFF == 0xFF -> (Trunc32to8 x) 643 (Trunc32to16 (And32 (Const32 [y]) x)) && y&0xFFFF == 0xFFFF -> (Trunc32to16 x) 644 (Trunc16to8 (And16 (Const16 [y]) x)) && y&0xFF == 0xFF -> (Trunc16to8 x) 645 646 (ZeroExt8to64 (Trunc64to8 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 56 -> x 647 (ZeroExt16to64 (Trunc64to16 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 48 -> x 648 (ZeroExt32to64 (Trunc64to32 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 32 -> x 649 (ZeroExt8to32 (Trunc32to8 x:(Rsh32Ux64 _ (Const64 [s])))) && s >= 24 -> x 650 (ZeroExt16to32 (Trunc32to16 x:(Rsh32Ux64 _ (Const64 [s])))) && s >= 16 -> x 651 (ZeroExt8to16 (Trunc16to8 x:(Rsh16Ux64 _ (Const64 [s])))) && s >= 8 -> x 652 653 (SignExt8to64 (Trunc64to8 x:(Rsh64x64 _ (Const64 [s])))) && s >= 56 -> x 654 (SignExt16to64 (Trunc64to16 x:(Rsh64x64 _ (Const64 [s])))) && s >= 48 -> x 655 (SignExt32to64 (Trunc64to32 x:(Rsh64x64 _ (Const64 [s])))) && s >= 32 -> x 656 (SignExt8to32 (Trunc32to8 x:(Rsh32x64 _ (Const64 [s])))) && s >= 24 -> x 657 (SignExt16to32 (Trunc32to16 x:(Rsh32x64 _ (Const64 [s])))) && s >= 16 -> x 658 (SignExt8to16 (Trunc16to8 x:(Rsh16x64 _ (Const64 [s])))) && s >= 8 -> x 659 660 (Slicemask (Const32 [x])) && x > 0 -> (Const32 [-1]) 661 (Slicemask (Const32 [0])) -> (Const32 [0]) 662 (Slicemask (Const64 [x])) && x > 0 -> (Const64 [-1]) 663 (Slicemask (Const64 [0])) -> (Const64 [0]) 664 665 // Rewrite AND of consts as shifts if possible, slightly faster for 64 bit operands 666 // leading zeros can be shifted left, then right 667 (And64 <t> (Const64 [y]) x) && nlz(y) + nto(y) == 64 && nto(y) >= 32 668 -> (Rsh64Ux64 (Lsh64x64 <t> x (Const64 <t> [nlz(y)])) (Const64 <t> [nlz(y)])) 669 // trailing zeros can be shifted right, then left 670 (And64 <t> (Const64 [y]) x) && nlo(y) + ntz(y) == 64 && ntz(y) >= 32 671 -> (Lsh64x64 (Rsh64Ux64 <t> x (Const64 <t> [ntz(y)])) (Const64 <t> [ntz(y)])) 672 673 // simplifications often used for lengths. e.g. len(s[i:i+5])==5 674 (Sub64 (Add64 x y) x) -> y 675 (Sub64 (Add64 x y) y) -> x 676 (Sub32 (Add32 x y) x) -> y 677 (Sub32 (Add32 x y) y) -> x 678 (Sub16 (Add16 x y) x) -> y 679 (Sub16 (Add16 x y) y) -> x 680 (Sub8 (Add8 x y) x) -> y 681 (Sub8 (Add8 x y) y) -> x 682 683 // basic phi simplifications 684 (Phi (Const8 [c]) (Const8 [c])) -> (Const8 [c]) 685 (Phi (Const16 [c]) (Const16 [c])) -> (Const16 [c]) 686 (Phi (Const32 [c]) (Const32 [c])) -> (Const32 [c]) 687 (Phi (Const64 [c]) (Const64 [c])) -> (Const64 [c]) 688 689 // user nil checks 690 (NeqPtr p (ConstNil)) -> (IsNonNil p) 691 (EqPtr p (ConstNil)) -> (Not (IsNonNil p)) 692 (IsNonNil (ConstNil)) -> (ConstBool [0]) 693 694 // slice and interface comparisons 695 // The frontend ensures that we can only compare against nil, 696 // so we need only compare the first word (interface type or slice ptr). 697 (EqInter x y) -> (EqPtr (ITab x) (ITab y)) 698 (NeqInter x y) -> (NeqPtr (ITab x) (ITab y)) 699 (EqSlice x y) -> (EqPtr (SlicePtr x) (SlicePtr y)) 700 (NeqSlice x y) -> (NeqPtr (SlicePtr x) (SlicePtr y)) 701 702 // Load of store of same address, with compatibly typed value and same size 703 (Load <t1> p1 (Store {t2} p2 x _)) && isSamePtr(p1,p2) && t1.Compare(x.Type) == types.CMPeq && t1.Size() == t2.(*types.Type).Size() -> x 704 705 // Eliminate stores of values that have just been loaded from the same location. 706 // We also handle the common case where there are some intermediate stores to non-overlapping struct fields. 707 (Store {t1} p1 (Load <t2> p2 mem) mem) && 708 isSamePtr(p1, p2) && 709 t2.Size() == t1.(*types.Type).Size() -> mem 710 (Store {t1} (OffPtr [o1] p1) (Load <t2> (OffPtr [o1] p2) oldmem) mem:(Store {t3} (OffPtr [o3] p3) _ oldmem)) && 711 isSamePtr(p1, p2) && 712 isSamePtr(p1, p3) && 713 t2.Size() == t1.(*types.Type).Size() && 714 !overlap(o1, t2.Size(), o3, t3.(*types.Type).Size()) -> mem 715 (Store {t1} (OffPtr [o1] p1) (Load <t2> (OffPtr [o1] p2) oldmem) mem:(Store {t3} (OffPtr [o3] p3) _ (Store {t4} (OffPtr [o4] p4) _ oldmem))) && 716 isSamePtr(p1, p2) && 717 isSamePtr(p1, p3) && 718 isSamePtr(p1, p4) && 719 t2.Size() == t1.(*types.Type).Size() && 720 !overlap(o1, t2.Size(), o3, t3.(*types.Type).Size()) && 721 !overlap(o1, t2.Size(), o4, t4.(*types.Type).Size()) -> mem 722 (Store {t1} (OffPtr [o1] p1) (Load <t2> (OffPtr [o1] p2) oldmem) mem:(Store {t3} (OffPtr [o3] p3) _ (Store {t4} (OffPtr [o4] p4) _ (Store {t5} (OffPtr [o5] p5) _ oldmem)))) && 723 isSamePtr(p1, p2) && 724 isSamePtr(p1, p3) && 725 isSamePtr(p1, p4) && 726 isSamePtr(p1, p5) && 727 t2.Size() == t1.(*types.Type).Size() && 728 !overlap(o1, t2.Size(), o3, t3.(*types.Type).Size()) && 729 !overlap(o1, t2.Size(), o4, t4.(*types.Type).Size()) && 730 !overlap(o1, t2.Size(), o5, t5.(*types.Type).Size()) -> mem 731 732 // Collapse OffPtr 733 (OffPtr (OffPtr p [b]) [a]) -> (OffPtr p [a+b]) 734 (OffPtr p [0]) && v.Type.Compare(p.Type) == types.CMPeq -> p 735 736 // indexing operations 737 // Note: bounds check has already been done 738 (PtrIndex <t> ptr idx) && config.PtrSize == 4 -> (AddPtr ptr (Mul32 <typ.Int> idx (Const32 <typ.Int> [t.ElemType().Size()]))) 739 (PtrIndex <t> ptr idx) && config.PtrSize == 8 -> (AddPtr ptr (Mul64 <typ.Int> idx (Const64 <typ.Int> [t.ElemType().Size()]))) 740 741 // struct operations 742 (StructSelect (StructMake1 x)) -> x 743 (StructSelect [0] (StructMake2 x _)) -> x 744 (StructSelect [1] (StructMake2 _ x)) -> x 745 (StructSelect [0] (StructMake3 x _ _)) -> x 746 (StructSelect [1] (StructMake3 _ x _)) -> x 747 (StructSelect [2] (StructMake3 _ _ x)) -> x 748 (StructSelect [0] (StructMake4 x _ _ _)) -> x 749 (StructSelect [1] (StructMake4 _ x _ _)) -> x 750 (StructSelect [2] (StructMake4 _ _ x _)) -> x 751 (StructSelect [3] (StructMake4 _ _ _ x)) -> x 752 753 (Load <t> _ _) && t.IsStruct() && t.NumFields() == 0 && fe.CanSSA(t) -> 754 (StructMake0) 755 (Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 1 && fe.CanSSA(t) -> 756 (StructMake1 757 (Load <t.FieldType(0)> (OffPtr <t.FieldType(0).PtrTo()> [0] ptr) mem)) 758 (Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 2 && fe.CanSSA(t) -> 759 (StructMake2 760 (Load <t.FieldType(0)> (OffPtr <t.FieldType(0).PtrTo()> [0] ptr) mem) 761 (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem)) 762 (Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 3 && fe.CanSSA(t) -> 763 (StructMake3 764 (Load <t.FieldType(0)> (OffPtr <t.FieldType(0).PtrTo()> [0] ptr) mem) 765 (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem) 766 (Load <t.FieldType(2)> (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] ptr) mem)) 767 (Load <t> ptr mem) && t.IsStruct() && t.NumFields() == 4 && fe.CanSSA(t) -> 768 (StructMake4 769 (Load <t.FieldType(0)> (OffPtr <t.FieldType(0).PtrTo()> [0] ptr) mem) 770 (Load <t.FieldType(1)> (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] ptr) mem) 771 (Load <t.FieldType(2)> (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] ptr) mem) 772 (Load <t.FieldType(3)> (OffPtr <t.FieldType(3).PtrTo()> [t.FieldOff(3)] ptr) mem)) 773 774 (StructSelect [i] x:(Load <t> ptr mem)) && !fe.CanSSA(t) -> 775 @x.Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [t.FieldOff(int(i))] ptr) mem) 776 777 (Store _ (StructMake0) mem) -> mem 778 (Store dst (StructMake1 <t> f0) mem) -> 779 (Store {t.FieldType(0)} (OffPtr <t.FieldType(0).PtrTo()> [0] dst) f0 mem) 780 (Store dst (StructMake2 <t> f0 f1) mem) -> 781 (Store {t.FieldType(1)} 782 (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst) 783 f1 784 (Store {t.FieldType(0)} 785 (OffPtr <t.FieldType(0).PtrTo()> [0] dst) 786 f0 mem)) 787 (Store dst (StructMake3 <t> f0 f1 f2) mem) -> 788 (Store {t.FieldType(2)} 789 (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] dst) 790 f2 791 (Store {t.FieldType(1)} 792 (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst) 793 f1 794 (Store {t.FieldType(0)} 795 (OffPtr <t.FieldType(0).PtrTo()> [0] dst) 796 f0 mem))) 797 (Store dst (StructMake4 <t> f0 f1 f2 f3) mem) -> 798 (Store {t.FieldType(3)} 799 (OffPtr <t.FieldType(3).PtrTo()> [t.FieldOff(3)] dst) 800 f3 801 (Store {t.FieldType(2)} 802 (OffPtr <t.FieldType(2).PtrTo()> [t.FieldOff(2)] dst) 803 f2 804 (Store {t.FieldType(1)} 805 (OffPtr <t.FieldType(1).PtrTo()> [t.FieldOff(1)] dst) 806 f1 807 (Store {t.FieldType(0)} 808 (OffPtr <t.FieldType(0).PtrTo()> [0] dst) 809 f0 mem)))) 810 811 // Putting struct{*byte} and similar into direct interfaces. 812 (IMake typ (StructMake1 val)) -> (IMake typ val) 813 (StructSelect [0] x:(IData _)) -> x 814 815 // un-SSAable values use mem->mem copies 816 (Store {t} dst (Load src mem) mem) && !fe.CanSSA(t.(*types.Type)) -> 817 (Move {t} [t.(*types.Type).Size()] dst src mem) 818 (Store {t} dst (Load src mem) (VarDef {x} mem)) && !fe.CanSSA(t.(*types.Type)) -> 819 (Move {t} [t.(*types.Type).Size()] dst src (VarDef {x} mem)) 820 821 // array ops 822 (ArraySelect (ArrayMake1 x)) -> x 823 824 (Load <t> _ _) && t.IsArray() && t.NumElem() == 0 -> 825 (ArrayMake0) 826 827 (Load <t> ptr mem) && t.IsArray() && t.NumElem() == 1 && fe.CanSSA(t) -> 828 (ArrayMake1 (Load <t.ElemType()> ptr mem)) 829 830 (Store _ (ArrayMake0) mem) -> mem 831 (Store dst (ArrayMake1 e) mem) -> (Store {e.Type} dst e mem) 832 833 (ArraySelect [0] (Load ptr mem)) -> (Load ptr mem) 834 835 // Putting [1]{*byte} and similar into direct interfaces. 836 (IMake typ (ArrayMake1 val)) -> (IMake typ val) 837 (ArraySelect [0] x:(IData _)) -> x 838 839 // string ops 840 // Decomposing StringMake and lowering of StringPtr and StringLen 841 // happens in a later pass, dec, so that these operations are available 842 // to other passes for optimizations. 843 (StringPtr (StringMake (Const64 <t> [c]) _)) -> (Const64 <t> [c]) 844 (StringLen (StringMake _ (Const64 <t> [c]))) -> (Const64 <t> [c]) 845 (ConstString {s}) && config.PtrSize == 4 && s.(string) == "" -> 846 (StringMake (ConstNil) (Const32 <typ.Int> [0])) 847 (ConstString {s}) && config.PtrSize == 8 && s.(string) == "" -> 848 (StringMake (ConstNil) (Const64 <typ.Int> [0])) 849 (ConstString {s}) && config.PtrSize == 4 && s.(string) != "" -> 850 (StringMake 851 (Addr <typ.BytePtr> {fe.StringData(s.(string))} 852 (SB)) 853 (Const32 <typ.Int> [int64(len(s.(string)))])) 854 (ConstString {s}) && config.PtrSize == 8 && s.(string) != "" -> 855 (StringMake 856 (Addr <typ.BytePtr> {fe.StringData(s.(string))} 857 (SB)) 858 (Const64 <typ.Int> [int64(len(s.(string)))])) 859 860 // slice ops 861 // Only a few slice rules are provided here. See dec.rules for 862 // a more comprehensive set. 863 (SliceLen (SliceMake _ (Const64 <t> [c]) _)) -> (Const64 <t> [c]) 864 (SliceCap (SliceMake _ _ (Const64 <t> [c]))) -> (Const64 <t> [c]) 865 (SliceLen (SliceMake _ (Const32 <t> [c]) _)) -> (Const32 <t> [c]) 866 (SliceCap (SliceMake _ _ (Const32 <t> [c]))) -> (Const32 <t> [c]) 867 (SlicePtr (SliceMake (SlicePtr x) _ _)) -> (SlicePtr x) 868 (SliceLen (SliceMake _ (SliceLen x) _)) -> (SliceLen x) 869 (SliceCap (SliceMake _ _ (SliceCap x))) -> (SliceCap x) 870 (SliceCap (SliceMake _ _ (SliceLen x))) -> (SliceLen x) 871 (ConstSlice) && config.PtrSize == 4 -> 872 (SliceMake 873 (ConstNil <v.Type.ElemType().PtrTo()>) 874 (Const32 <typ.Int> [0]) 875 (Const32 <typ.Int> [0])) 876 (ConstSlice) && config.PtrSize == 8 -> 877 (SliceMake 878 (ConstNil <v.Type.ElemType().PtrTo()>) 879 (Const64 <typ.Int> [0]) 880 (Const64 <typ.Int> [0])) 881 882 // interface ops 883 (ConstInterface) -> 884 (IMake 885 (ConstNil <typ.BytePtr>) 886 (ConstNil <typ.BytePtr>)) 887 888 (NilCheck (GetG mem) mem) -> mem 889 890 (If (Not cond) yes no) -> (If cond no yes) 891 (If (ConstBool [c]) yes no) && c == 1 -> (First nil yes no) 892 (If (ConstBool [c]) yes no) && c == 0 -> (First nil no yes) 893 894 // Get rid of Convert ops for pointer arithmetic on unsafe.Pointer. 895 (Convert (Add64 (Convert ptr mem) off) mem) -> (Add64 ptr off) 896 (Convert (Convert ptr mem) mem) -> ptr 897 898 // Decompose compound argument values 899 (Arg {n} [off]) && v.Type.IsString() -> 900 (StringMake 901 (Arg <typ.BytePtr> {n} [off]) 902 (Arg <typ.Int> {n} [off+config.PtrSize])) 903 904 (Arg {n} [off]) && v.Type.IsSlice() -> 905 (SliceMake 906 (Arg <v.Type.ElemType().PtrTo()> {n} [off]) 907 (Arg <typ.Int> {n} [off+config.PtrSize]) 908 (Arg <typ.Int> {n} [off+2*config.PtrSize])) 909 910 (Arg {n} [off]) && v.Type.IsInterface() -> 911 (IMake 912 (Arg <typ.BytePtr> {n} [off]) 913 (Arg <typ.BytePtr> {n} [off+config.PtrSize])) 914 915 (Arg {n} [off]) && v.Type.IsComplex() && v.Type.Size() == 16 -> 916 (ComplexMake 917 (Arg <typ.Float64> {n} [off]) 918 (Arg <typ.Float64> {n} [off+8])) 919 920 (Arg {n} [off]) && v.Type.IsComplex() && v.Type.Size() == 8 -> 921 (ComplexMake 922 (Arg <typ.Float32> {n} [off]) 923 (Arg <typ.Float32> {n} [off+4])) 924 925 (Arg <t>) && t.IsStruct() && t.NumFields() == 0 && fe.CanSSA(t) -> 926 (StructMake0) 927 (Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 1 && fe.CanSSA(t) -> 928 (StructMake1 929 (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)])) 930 (Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 2 && fe.CanSSA(t) -> 931 (StructMake2 932 (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)]) 933 (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)])) 934 (Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 3 && fe.CanSSA(t) -> 935 (StructMake3 936 (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)]) 937 (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)]) 938 (Arg <t.FieldType(2)> {n} [off+t.FieldOff(2)])) 939 (Arg <t> {n} [off]) && t.IsStruct() && t.NumFields() == 4 && fe.CanSSA(t) -> 940 (StructMake4 941 (Arg <t.FieldType(0)> {n} [off+t.FieldOff(0)]) 942 (Arg <t.FieldType(1)> {n} [off+t.FieldOff(1)]) 943 (Arg <t.FieldType(2)> {n} [off+t.FieldOff(2)]) 944 (Arg <t.FieldType(3)> {n} [off+t.FieldOff(3)])) 945 946 (Arg <t>) && t.IsArray() && t.NumElem() == 0 -> 947 (ArrayMake0) 948 (Arg <t> {n} [off]) && t.IsArray() && t.NumElem() == 1 && fe.CanSSA(t) -> 949 (ArrayMake1 (Arg <t.ElemType()> {n} [off])) 950 951 // strength reduction of divide by a constant. 952 // See ../magic.go for a detailed description of these algorithms. 953 954 // Unsigned divide by power of 2. Strength reduce to a shift. 955 (Div8u n (Const8 [c])) && isPowerOfTwo(c&0xff) -> (Rsh8Ux64 n (Const64 <typ.UInt64> [log2(c&0xff)])) 956 (Div16u n (Const16 [c])) && isPowerOfTwo(c&0xffff) -> (Rsh16Ux64 n (Const64 <typ.UInt64> [log2(c&0xffff)])) 957 (Div32u n (Const32 [c])) && isPowerOfTwo(c&0xffffffff) -> (Rsh32Ux64 n (Const64 <typ.UInt64> [log2(c&0xffffffff)])) 958 (Div64u n (Const64 [c])) && isPowerOfTwo(c) -> (Rsh64Ux64 n (Const64 <typ.UInt64> [log2(c)])) 959 960 // Unsigned divide, not a power of 2. Strength reduce to a multiply. 961 // For 8-bit divides, we just do a direct 9-bit by 8-bit multiply. 962 (Div8u x (Const8 [c])) && umagicOK(8, c) -> 963 (Trunc32to8 964 (Rsh32Ux64 <typ.UInt32> 965 (Mul32 <typ.UInt32> 966 (Const32 <typ.UInt32> [int64(1<<8+umagic(8,c).m)]) 967 (ZeroExt8to32 x)) 968 (Const64 <typ.UInt64> [8+umagic(8,c).s]))) 969 970 // For 16-bit divides on 64-bit machines, we do a direct 17-bit by 16-bit multiply. 971 (Div16u x (Const16 [c])) && umagicOK(16, c) && config.RegSize == 8 -> 972 (Trunc64to16 973 (Rsh64Ux64 <typ.UInt64> 974 (Mul64 <typ.UInt64> 975 (Const64 <typ.UInt64> [int64(1<<16+umagic(16,c).m)]) 976 (ZeroExt16to64 x)) 977 (Const64 <typ.UInt64> [16+umagic(16,c).s]))) 978 979 // For 16-bit divides on 32-bit machines 980 (Div16u x (Const16 [c])) && umagicOK(16, c) && config.RegSize == 4 && umagic(16,c).m&1 == 0 -> 981 (Trunc32to16 982 (Rsh32Ux64 <typ.UInt32> 983 (Mul32 <typ.UInt32> 984 (Const32 <typ.UInt32> [int64(1<<15+umagic(16,c).m/2)]) 985 (ZeroExt16to32 x)) 986 (Const64 <typ.UInt64> [16+umagic(16,c).s-1]))) 987 (Div16u x (Const16 [c])) && umagicOK(16, c) && config.RegSize == 4 && c&1 == 0 -> 988 (Trunc32to16 989 (Rsh32Ux64 <typ.UInt32> 990 (Mul32 <typ.UInt32> 991 (Const32 <typ.UInt32> [int64(1<<15+(umagic(16,c).m+1)/2)]) 992 (Rsh32Ux64 <typ.UInt32> (ZeroExt16to32 x) (Const64 <typ.UInt64> [1]))) 993 (Const64 <typ.UInt64> [16+umagic(16,c).s-2]))) 994 (Div16u x (Const16 [c])) && umagicOK(16, c) && config.RegSize == 4 -> 995 (Trunc32to16 996 (Rsh32Ux64 <typ.UInt32> 997 (Avg32u 998 (Lsh32x64 <typ.UInt32> (ZeroExt16to32 x) (Const64 <typ.UInt64> [16])) 999 (Mul32 <typ.UInt32> 1000 (Const32 <typ.UInt32> [int64(umagic(16,c).m)]) 1001 (ZeroExt16to32 x))) 1002 (Const64 <typ.UInt64> [16+umagic(16,c).s-1]))) 1003 1004 // For 32-bit divides on 32-bit machines 1005 (Div32u x (Const32 [c])) && umagicOK(32, c) && config.RegSize == 4 && umagic(32,c).m&1 == 0 -> 1006 (Rsh32Ux64 <typ.UInt32> 1007 (Hmul32u <typ.UInt32> 1008 (Const32 <typ.UInt32> [int64(int32(1<<31+umagic(32,c).m/2))]) 1009 x) 1010 (Const64 <typ.UInt64> [umagic(32,c).s-1])) 1011 (Div32u x (Const32 [c])) && umagicOK(32, c) && config.RegSize == 4 && c&1 == 0 -> 1012 (Rsh32Ux64 <typ.UInt32> 1013 (Hmul32u <typ.UInt32> 1014 (Const32 <typ.UInt32> [int64(int32(1<<31+(umagic(32,c).m+1)/2))]) 1015 (Rsh32Ux64 <typ.UInt32> x (Const64 <typ.UInt64> [1]))) 1016 (Const64 <typ.UInt64> [umagic(32,c).s-2])) 1017 (Div32u x (Const32 [c])) && umagicOK(32, c) && config.RegSize == 4 -> 1018 (Rsh32Ux64 <typ.UInt32> 1019 (Avg32u 1020 x 1021 (Hmul32u <typ.UInt32> 1022 (Const32 <typ.UInt32> [int64(int32(umagic(32,c).m))]) 1023 x)) 1024 (Const64 <typ.UInt64> [umagic(32,c).s-1])) 1025 1026 // For 32-bit divides on 64-bit machines 1027 // We'll use a regular (non-hi) multiply for this case. 1028 (Div32u x (Const32 [c])) && umagicOK(32, c) && config.RegSize == 8 && umagic(32,c).m&1 == 0 -> 1029 (Trunc64to32 1030 (Rsh64Ux64 <typ.UInt64> 1031 (Mul64 <typ.UInt64> 1032 (Const64 <typ.UInt64> [int64(1<<31+umagic(32,c).m/2)]) 1033 (ZeroExt32to64 x)) 1034 (Const64 <typ.UInt64> [32+umagic(32,c).s-1]))) 1035 (Div32u x (Const32 [c])) && umagicOK(32, c) && config.RegSize == 8 && c&1 == 0 -> 1036 (Trunc64to32 1037 (Rsh64Ux64 <typ.UInt64> 1038 (Mul64 <typ.UInt64> 1039 (Const64 <typ.UInt64> [int64(1<<31+(umagic(32,c).m+1)/2)]) 1040 (Rsh64Ux64 <typ.UInt64> (ZeroExt32to64 x) (Const64 <typ.UInt64> [1]))) 1041 (Const64 <typ.UInt64> [32+umagic(32,c).s-2]))) 1042 (Div32u x (Const32 [c])) && umagicOK(32, c) && config.RegSize == 8 -> 1043 (Trunc64to32 1044 (Rsh64Ux64 <typ.UInt64> 1045 (Avg64u 1046 (Lsh64x64 <typ.UInt64> (ZeroExt32to64 x) (Const64 <typ.UInt64> [32])) 1047 (Mul64 <typ.UInt64> 1048 (Const64 <typ.UInt32> [int64(umagic(32,c).m)]) 1049 (ZeroExt32to64 x))) 1050 (Const64 <typ.UInt64> [32+umagic(32,c).s-1]))) 1051 1052 // For 64-bit divides on 64-bit machines 1053 // (64-bit divides on 32-bit machines are lowered to a runtime call by the walk pass.) 1054 (Div64u x (Const64 [c])) && umagicOK(64, c) && config.RegSize == 8 && umagic(64,c).m&1 == 0 -> 1055 (Rsh64Ux64 <typ.UInt64> 1056 (Hmul64u <typ.UInt64> 1057 (Const64 <typ.UInt64> [int64(1<<63+umagic(64,c).m/2)]) 1058 x) 1059 (Const64 <typ.UInt64> [umagic(64,c).s-1])) 1060 (Div64u x (Const64 [c])) && umagicOK(64, c) && config.RegSize == 8 && c&1 == 0 -> 1061 (Rsh64Ux64 <typ.UInt64> 1062 (Hmul64u <typ.UInt64> 1063 (Const64 <typ.UInt64> [int64(1<<63+(umagic(64,c).m+1)/2)]) 1064 (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [1]))) 1065 (Const64 <typ.UInt64> [umagic(64,c).s-2])) 1066 (Div64u x (Const64 [c])) && umagicOK(64, c) && config.RegSize == 8 -> 1067 (Rsh64Ux64 <typ.UInt64> 1068 (Avg64u 1069 x 1070 (Hmul64u <typ.UInt64> 1071 (Const64 <typ.UInt64> [int64(umagic(64,c).m)]) 1072 x)) 1073 (Const64 <typ.UInt64> [umagic(64,c).s-1])) 1074 1075 // Signed divide by a negative constant. Rewrite to divide by a positive constant. 1076 (Div8 <t> n (Const8 [c])) && c < 0 && c != -1<<7 -> (Neg8 (Div8 <t> n (Const8 <t> [-c]))) 1077 (Div16 <t> n (Const16 [c])) && c < 0 && c != -1<<15 -> (Neg16 (Div16 <t> n (Const16 <t> [-c]))) 1078 (Div32 <t> n (Const32 [c])) && c < 0 && c != -1<<31 -> (Neg32 (Div32 <t> n (Const32 <t> [-c]))) 1079 (Div64 <t> n (Const64 [c])) && c < 0 && c != -1<<63 -> (Neg64 (Div64 <t> n (Const64 <t> [-c]))) 1080 1081 // Dividing by the most-negative number. Result is always 0 except 1082 // if the input is also the most-negative number. 1083 // We can detect that using the sign bit of x & -x. 1084 (Div8 <t> x (Const8 [-1<<7 ])) -> (Rsh8Ux64 (And8 <t> x (Neg8 <t> x)) (Const64 <typ.UInt64> [7 ])) 1085 (Div16 <t> x (Const16 [-1<<15])) -> (Rsh16Ux64 (And16 <t> x (Neg16 <t> x)) (Const64 <typ.UInt64> [15])) 1086 (Div32 <t> x (Const32 [-1<<31])) -> (Rsh32Ux64 (And32 <t> x (Neg32 <t> x)) (Const64 <typ.UInt64> [31])) 1087 (Div64 <t> x (Const64 [-1<<63])) -> (Rsh64Ux64 (And64 <t> x (Neg64 <t> x)) (Const64 <typ.UInt64> [63])) 1088 1089 // Signed divide by power of 2. 1090 // n / c = n >> log(c) if n >= 0 1091 // = (n+c-1) >> log(c) if n < 0 1092 // We conditionally add c-1 by adding n>>63>>(64-log(c)) (first shift signed, second shift unsigned). 1093 (Div8 <t> n (Const8 [c])) && isPowerOfTwo(c) -> 1094 (Rsh8x64 1095 (Add8 <t> n (Rsh8Ux64 <t> (Rsh8x64 <t> n (Const64 <typ.UInt64> [ 7])) (Const64 <typ.UInt64> [ 8-log2(c)]))) 1096 (Const64 <typ.UInt64> [log2(c)])) 1097 (Div16 <t> n (Const16 [c])) && isPowerOfTwo(c) -> 1098 (Rsh16x64 1099 (Add16 <t> n (Rsh16Ux64 <t> (Rsh16x64 <t> n (Const64 <typ.UInt64> [15])) (Const64 <typ.UInt64> [16-log2(c)]))) 1100 (Const64 <typ.UInt64> [log2(c)])) 1101 (Div32 <t> n (Const32 [c])) && isPowerOfTwo(c) -> 1102 (Rsh32x64 1103 (Add32 <t> n (Rsh32Ux64 <t> (Rsh32x64 <t> n (Const64 <typ.UInt64> [31])) (Const64 <typ.UInt64> [32-log2(c)]))) 1104 (Const64 <typ.UInt64> [log2(c)])) 1105 (Div64 <t> n (Const64 [c])) && isPowerOfTwo(c) -> 1106 (Rsh64x64 1107 (Add64 <t> n (Rsh64Ux64 <t> (Rsh64x64 <t> n (Const64 <typ.UInt64> [63])) (Const64 <typ.UInt64> [64-log2(c)]))) 1108 (Const64 <typ.UInt64> [log2(c)])) 1109 1110 // Signed divide, not a power of 2. Strength reduce to a multiply. 1111 (Div8 <t> x (Const8 [c])) && smagicOK(8,c) -> 1112 (Sub8 <t> 1113 (Rsh32x64 <t> 1114 (Mul32 <typ.UInt32> 1115 (Const32 <typ.UInt32> [int64(smagic(8,c).m)]) 1116 (SignExt8to32 x)) 1117 (Const64 <typ.UInt64> [8+smagic(8,c).s])) 1118 (Rsh32x64 <t> 1119 (SignExt8to32 x) 1120 (Const64 <typ.UInt64> [31]))) 1121 (Div16 <t> x (Const16 [c])) && smagicOK(16,c) -> 1122 (Sub16 <t> 1123 (Rsh32x64 <t> 1124 (Mul32 <typ.UInt32> 1125 (Const32 <typ.UInt32> [int64(smagic(16,c).m)]) 1126 (SignExt16to32 x)) 1127 (Const64 <typ.UInt64> [16+smagic(16,c).s])) 1128 (Rsh32x64 <t> 1129 (SignExt16to32 x) 1130 (Const64 <typ.UInt64> [31]))) 1131 (Div32 <t> x (Const32 [c])) && smagicOK(32,c) && config.RegSize == 8 -> 1132 (Sub32 <t> 1133 (Rsh64x64 <t> 1134 (Mul64 <typ.UInt64> 1135 (Const64 <typ.UInt64> [int64(smagic(32,c).m)]) 1136 (SignExt32to64 x)) 1137 (Const64 <typ.UInt64> [32+smagic(32,c).s])) 1138 (Rsh64x64 <t> 1139 (SignExt32to64 x) 1140 (Const64 <typ.UInt64> [63]))) 1141 (Div32 <t> x (Const32 [c])) && smagicOK(32,c) && config.RegSize == 4 && smagic(32,c).m&1 == 0 -> 1142 (Sub32 <t> 1143 (Rsh32x64 <t> 1144 (Hmul32 <t> 1145 (Const32 <typ.UInt32> [int64(int32(smagic(32,c).m/2))]) 1146 x) 1147 (Const64 <typ.UInt64> [smagic(32,c).s-1])) 1148 (Rsh32x64 <t> 1149 x 1150 (Const64 <typ.UInt64> [31]))) 1151 (Div32 <t> x (Const32 [c])) && smagicOK(32,c) && config.RegSize == 4 && smagic(32,c).m&1 != 0 -> 1152 (Sub32 <t> 1153 (Rsh32x64 <t> 1154 (Add32 <t> 1155 (Hmul32 <t> 1156 (Const32 <typ.UInt32> [int64(int32(smagic(32,c).m))]) 1157 x) 1158 x) 1159 (Const64 <typ.UInt64> [smagic(32,c).s])) 1160 (Rsh32x64 <t> 1161 x 1162 (Const64 <typ.UInt64> [31]))) 1163 (Div64 <t> x (Const64 [c])) && smagicOK(64,c) && smagic(64,c).m&1 == 0 -> 1164 (Sub64 <t> 1165 (Rsh64x64 <t> 1166 (Hmul64 <t> 1167 (Const64 <typ.UInt64> [int64(smagic(64,c).m/2)]) 1168 x) 1169 (Const64 <typ.UInt64> [smagic(64,c).s-1])) 1170 (Rsh64x64 <t> 1171 x 1172 (Const64 <typ.UInt64> [63]))) 1173 (Div64 <t> x (Const64 [c])) && smagicOK(64,c) && smagic(64,c).m&1 != 0 -> 1174 (Sub64 <t> 1175 (Rsh64x64 <t> 1176 (Add64 <t> 1177 (Hmul64 <t> 1178 (Const64 <typ.UInt64> [int64(smagic(64,c).m)]) 1179 x) 1180 x) 1181 (Const64 <typ.UInt64> [smagic(64,c).s])) 1182 (Rsh64x64 <t> 1183 x 1184 (Const64 <typ.UInt64> [63]))) 1185 1186 // Unsigned mod by power of 2 constant. 1187 (Mod8u <t> n (Const8 [c])) && isPowerOfTwo(c&0xff) -> (And8 n (Const8 <t> [(c&0xff)-1])) 1188 (Mod16u <t> n (Const16 [c])) && isPowerOfTwo(c&0xffff) -> (And16 n (Const16 <t> [(c&0xffff)-1])) 1189 (Mod32u <t> n (Const32 [c])) && isPowerOfTwo(c&0xffffffff) -> (And32 n (Const32 <t> [(c&0xffffffff)-1])) 1190 (Mod64u <t> n (Const64 [c])) && isPowerOfTwo(c) -> (And64 n (Const64 <t> [c-1])) 1191 1192 // Signed mod by negative constant. 1193 (Mod8 <t> n (Const8 [c])) && c < 0 && c != -1<<7 -> (Mod8 <t> n (Const8 <t> [-c])) 1194 (Mod16 <t> n (Const16 [c])) && c < 0 && c != -1<<15 -> (Mod16 <t> n (Const16 <t> [-c])) 1195 (Mod32 <t> n (Const32 [c])) && c < 0 && c != -1<<31 -> (Mod32 <t> n (Const32 <t> [-c])) 1196 (Mod64 <t> n (Const64 [c])) && c < 0 && c != -1<<63 -> (Mod64 <t> n (Const64 <t> [-c])) 1197 1198 // All other mods by constants, do A%B = A-(A/B*B). 1199 // This implements % with two * and a bunch of ancillary ops. 1200 // One of the * is free if the user's code also computes A/B. 1201 (Mod8 <t> x (Const8 [c])) && x.Op != OpConst8 && (c > 0 || c == -1<<7) 1202 -> (Sub8 x (Mul8 <t> (Div8 <t> x (Const8 <t> [c])) (Const8 <t> [c]))) 1203 (Mod16 <t> x (Const16 [c])) && x.Op != OpConst16 && (c > 0 || c == -1<<15) 1204 -> (Sub16 x (Mul16 <t> (Div16 <t> x (Const16 <t> [c])) (Const16 <t> [c]))) 1205 (Mod32 <t> x (Const32 [c])) && x.Op != OpConst32 && (c > 0 || c == -1<<31) 1206 -> (Sub32 x (Mul32 <t> (Div32 <t> x (Const32 <t> [c])) (Const32 <t> [c]))) 1207 (Mod64 <t> x (Const64 [c])) && x.Op != OpConst64 && (c > 0 || c == -1<<63) 1208 -> (Sub64 x (Mul64 <t> (Div64 <t> x (Const64 <t> [c])) (Const64 <t> [c]))) 1209 (Mod8u <t> x (Const8 [c])) && x.Op != OpConst8 && c > 0 && umagicOK(8 ,c) 1210 -> (Sub8 x (Mul8 <t> (Div8u <t> x (Const8 <t> [c])) (Const8 <t> [c]))) 1211 (Mod16u <t> x (Const16 [c])) && x.Op != OpConst16 && c > 0 && umagicOK(16,c) 1212 -> (Sub16 x (Mul16 <t> (Div16u <t> x (Const16 <t> [c])) (Const16 <t> [c]))) 1213 (Mod32u <t> x (Const32 [c])) && x.Op != OpConst32 && c > 0 && umagicOK(32,c) 1214 -> (Sub32 x (Mul32 <t> (Div32u <t> x (Const32 <t> [c])) (Const32 <t> [c]))) 1215 (Mod64u <t> x (Const64 [c])) && x.Op != OpConst64 && c > 0 && umagicOK(64,c) 1216 -> (Sub64 x (Mul64 <t> (Div64u <t> x (Const64 <t> [c])) (Const64 <t> [c]))) 1217 1218 // Reassociate expressions involving 1219 // constants such that constants come first, 1220 // exposing obvious constant-folding opportunities. 1221 // Reassociate (op (op y C) x) to (op C (op x y)) or similar, where C 1222 // is constant, which pushes constants to the outside 1223 // of the expression. At that point, any constant-folding 1224 // opportunities should be obvious. 1225 1226 // x + (C + z) -> C + (x + z) 1227 (Add64 (Add64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Add64 i (Add64 <t> z x)) 1228 (Add32 (Add32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Add32 i (Add32 <t> z x)) 1229 (Add16 (Add16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Add16 i (Add16 <t> z x)) 1230 (Add8 (Add8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Add8 i (Add8 <t> z x)) 1231 1232 // x + (C - z) -> C + (x - z) 1233 (Add64 (Sub64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Add64 i (Sub64 <t> x z)) 1234 (Add32 (Sub32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Add32 i (Sub32 <t> x z)) 1235 (Add16 (Sub16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Add16 i (Sub16 <t> x z)) 1236 (Add8 (Sub8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Add8 i (Sub8 <t> x z)) 1237 (Add64 x (Sub64 i:(Const64 <t>) z)) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Add64 i (Sub64 <t> x z)) 1238 (Add32 x (Sub32 i:(Const32 <t>) z)) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Add32 i (Sub32 <t> x z)) 1239 (Add16 x (Sub16 i:(Const16 <t>) z)) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Add16 i (Sub16 <t> x z)) 1240 (Add8 x (Sub8 i:(Const8 <t>) z)) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Add8 i (Sub8 <t> x z)) 1241 1242 // x + (z - C) -> (x + z) - C 1243 (Add64 (Sub64 z i:(Const64 <t>)) x) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Sub64 (Add64 <t> x z) i) 1244 (Add32 (Sub32 z i:(Const32 <t>)) x) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Sub32 (Add32 <t> x z) i) 1245 (Add16 (Sub16 z i:(Const16 <t>)) x) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Sub16 (Add16 <t> x z) i) 1246 (Add8 (Sub8 z i:(Const8 <t>)) x) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Sub8 (Add8 <t> x z) i) 1247 (Add64 x (Sub64 z i:(Const64 <t>))) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Sub64 (Add64 <t> x z) i) 1248 (Add32 x (Sub32 z i:(Const32 <t>))) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Sub32 (Add32 <t> x z) i) 1249 (Add16 x (Sub16 z i:(Const16 <t>))) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Sub16 (Add16 <t> x z) i) 1250 (Add8 x (Sub8 z i:(Const8 <t>))) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Sub8 (Add8 <t> x z) i) 1251 1252 // x - (C - z) -> x + (z - C) -> (x + z) - C 1253 (Sub64 x (Sub64 i:(Const64 <t>) z)) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Sub64 (Add64 <t> x z) i) 1254 (Sub32 x (Sub32 i:(Const32 <t>) z)) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Sub32 (Add32 <t> x z) i) 1255 (Sub16 x (Sub16 i:(Const16 <t>) z)) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Sub16 (Add16 <t> x z) i) 1256 (Sub8 x (Sub8 i:(Const8 <t>) z)) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Sub8 (Add8 <t> x z) i) 1257 1258 // x - (z - C) -> x + (C - z) -> (x - z) + C 1259 (Sub64 x (Sub64 z i:(Const64 <t>))) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Add64 i (Sub64 <t> x z)) 1260 (Sub32 x (Sub32 z i:(Const32 <t>))) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Add32 i (Sub32 <t> x z)) 1261 (Sub16 x (Sub16 z i:(Const16 <t>))) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Add16 i (Sub16 <t> x z)) 1262 (Sub8 x (Sub8 z i:(Const8 <t>))) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Add8 i (Sub8 <t> x z)) 1263 1264 // x & (C & z) -> C & (x & z) 1265 (And64 (And64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) -> (And64 i (And64 <t> z x)) 1266 (And32 (And32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) -> (And32 i (And32 <t> z x)) 1267 (And16 (And16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) -> (And16 i (And16 <t> z x)) 1268 (And8 (And8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) -> (And8 i (And8 <t> z x)) 1269 1270 // x | (C | z) -> C | (x | z) 1271 (Or64 (Or64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Or64 i (Or64 <t> z x)) 1272 (Or32 (Or32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Or32 i (Or32 <t> z x)) 1273 (Or16 (Or16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Or16 i (Or16 <t> z x)) 1274 (Or8 (Or8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Or8 i (Or8 <t> z x)) 1275 1276 // x ^ (C ^ z) -> C ^ (x ^ z) 1277 (Xor64 (Xor64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) -> (Xor64 i (Xor64 <t> z x)) 1278 (Xor32 (Xor32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) -> (Xor32 i (Xor32 <t> z x)) 1279 (Xor16 (Xor16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) -> (Xor16 i (Xor16 <t> z x)) 1280 (Xor8 (Xor8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) -> (Xor8 i (Xor8 <t> z x)) 1281 1282 // C + (D + x) -> (C + D) + x 1283 (Add64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) -> (Add64 (Const64 <t> [c+d]) x) 1284 (Add32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) -> (Add32 (Const32 <t> [int64(int32(c+d))]) x) 1285 (Add16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) -> (Add16 (Const16 <t> [int64(int16(c+d))]) x) 1286 (Add8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) -> (Add8 (Const8 <t> [int64(int8(c+d))]) x) 1287 1288 // C + (D - x) -> (C + D) - x 1289 (Add64 (Const64 <t> [c]) (Sub64 (Const64 <t> [d]) x)) -> (Sub64 (Const64 <t> [c+d]) x) 1290 (Add32 (Const32 <t> [c]) (Sub32 (Const32 <t> [d]) x)) -> (Sub32 (Const32 <t> [int64(int32(c+d))]) x) 1291 (Add16 (Const16 <t> [c]) (Sub16 (Const16 <t> [d]) x)) -> (Sub16 (Const16 <t> [int64(int16(c+d))]) x) 1292 (Add8 (Const8 <t> [c]) (Sub8 (Const8 <t> [d]) x)) -> (Sub8 (Const8 <t> [int64(int8(c+d))]) x) 1293 1294 // C + (x - D) -> (C - D) + x 1295 (Add64 (Const64 <t> [c]) (Sub64 x (Const64 <t> [d]))) -> (Add64 (Const64 <t> [c-d]) x) 1296 (Add32 (Const32 <t> [c]) (Sub32 x (Const32 <t> [d]))) -> (Add32 (Const32 <t> [int64(int32(c-d))]) x) 1297 (Add16 (Const16 <t> [c]) (Sub16 x (Const16 <t> [d]))) -> (Add16 (Const16 <t> [int64(int16(c-d))]) x) 1298 (Add8 (Const8 <t> [c]) (Sub8 x (Const8 <t> [d]))) -> (Add8 (Const8 <t> [int64(int8(c-d))]) x) 1299 1300 // C - (x - D) -> (C + D) - x 1301 (Sub64 (Const64 <t> [c]) (Sub64 x (Const64 <t> [d]))) -> (Sub64 (Const64 <t> [c+d]) x) 1302 (Sub32 (Const32 <t> [c]) (Sub32 x (Const32 <t> [d]))) -> (Sub32 (Const32 <t> [int64(int32(c+d))]) x) 1303 (Sub16 (Const16 <t> [c]) (Sub16 x (Const16 <t> [d]))) -> (Sub16 (Const16 <t> [int64(int16(c+d))]) x) 1304 (Sub8 (Const8 <t> [c]) (Sub8 x (Const8 <t> [d]))) -> (Sub8 (Const8 <t> [int64(int8(c+d))]) x) 1305 1306 // C - (D - x) -> (C - D) + x 1307 (Sub64 (Const64 <t> [c]) (Sub64 (Const64 <t> [d]) x)) -> (Add64 (Const64 <t> [c-d]) x) 1308 (Sub32 (Const32 <t> [c]) (Sub32 (Const32 <t> [d]) x)) -> (Add32 (Const32 <t> [int64(int32(c-d))]) x) 1309 (Sub16 (Const16 <t> [c]) (Sub16 (Const16 <t> [d]) x)) -> (Add16 (Const16 <t> [int64(int16(c-d))]) x) 1310 (Sub8 (Const8 <t> [c]) (Sub8 (Const8 <t> [d]) x)) -> (Add8 (Const8 <t> [int64(int8(c-d))]) x) 1311 1312 // C & (D & x) -> (C & D) & x 1313 (And64 (Const64 <t> [c]) (And64 (Const64 <t> [d]) x)) -> (And64 (Const64 <t> [c&d]) x) 1314 (And32 (Const32 <t> [c]) (And32 (Const32 <t> [d]) x)) -> (And32 (Const32 <t> [int64(int32(c&d))]) x) 1315 (And16 (Const16 <t> [c]) (And16 (Const16 <t> [d]) x)) -> (And16 (Const16 <t> [int64(int16(c&d))]) x) 1316 (And8 (Const8 <t> [c]) (And8 (Const8 <t> [d]) x)) -> (And8 (Const8 <t> [int64(int8(c&d))]) x) 1317 1318 // C | (D | x) -> (C | D) | x 1319 (Or64 (Const64 <t> [c]) (Or64 (Const64 <t> [d]) x)) -> (Or64 (Const64 <t> [c|d]) x) 1320 (Or32 (Const32 <t> [c]) (Or32 (Const32 <t> [d]) x)) -> (Or32 (Const32 <t> [int64(int32(c|d))]) x) 1321 (Or16 (Const16 <t> [c]) (Or16 (Const16 <t> [d]) x)) -> (Or16 (Const16 <t> [int64(int16(c|d))]) x) 1322 (Or8 (Const8 <t> [c]) (Or8 (Const8 <t> [d]) x)) -> (Or8 (Const8 <t> [int64(int8(c|d))]) x) 1323 1324 // C ^ (D ^ x) -> (C ^ D) ^ x 1325 (Xor64 (Const64 <t> [c]) (Xor64 (Const64 <t> [d]) x)) -> (Xor64 (Const64 <t> [c^d]) x) 1326 (Xor32 (Const32 <t> [c]) (Xor32 (Const32 <t> [d]) x)) -> (Xor32 (Const32 <t> [int64(int32(c^d))]) x) 1327 (Xor16 (Const16 <t> [c]) (Xor16 (Const16 <t> [d]) x)) -> (Xor16 (Const16 <t> [int64(int16(c^d))]) x) 1328 (Xor8 (Const8 <t> [c]) (Xor8 (Const8 <t> [d]) x)) -> (Xor8 (Const8 <t> [int64(int8(c^d))]) x) 1329 1330 // C * (D * x) = (C * D) * x 1331 (Mul64 (Const64 <t> [c]) (Mul64 (Const64 <t> [d]) x)) -> (Mul64 (Const64 <t> [c*d]) x) 1332 (Mul32 (Const32 <t> [c]) (Mul32 (Const32 <t> [d]) x)) -> (Mul32 (Const32 <t> [int64(int32(c*d))]) x) 1333 (Mul16 (Const16 <t> [c]) (Mul16 (Const16 <t> [d]) x)) -> (Mul16 (Const16 <t> [int64(int16(c*d))]) x) 1334 (Mul8 (Const8 <t> [c]) (Mul8 (Const8 <t> [d]) x)) -> (Mul8 (Const8 <t> [int64(int8(c*d))]) x) 1335 1336 // floating point optimizations 1337 (Add32F x (Const32F [0])) -> x 1338 (Add64F x (Const64F [0])) -> x 1339 (Sub32F x (Const32F [0])) -> x 1340 (Sub64F x (Const64F [0])) -> x 1341 (Mul32F x (Const32F [f2i(1)])) -> x 1342 (Mul64F x (Const64F [f2i(1)])) -> x 1343 (Mul32F x (Const32F [f2i(-1)])) -> (Neg32F x) 1344 (Mul64F x (Const64F [f2i(-1)])) -> (Neg64F x) 1345 (Mul32F x (Const32F [f2i(2)])) -> (Add32F x x) 1346 (Mul64F x (Const64F [f2i(2)])) -> (Add64F x x) 1347 (Div32F x (Const32F <t> [c])) && reciprocalExact32(float32(i2f(c))) -> (Mul32F x (Const32F <t> [f2i(1/i2f(c))])) 1348 (Div64F x (Const64F <t> [c])) && reciprocalExact64(i2f(c)) -> (Mul64F x (Const64F <t> [f2i(1/i2f(c))])) 1349 1350 (Sqrt (Const64F [c])) -> (Const64F [f2i(math.Sqrt(i2f(c)))]) 1351 1352 // recognize runtime.newobject and don't Zero/Nilcheck it 1353 (Zero (Load (OffPtr [c] (SP)) mem) mem) 1354 && mem.Op == OpStaticCall 1355 && isSameSym(mem.Aux, "runtime.newobject") 1356 && c == config.ctxt.FixedFrameSize() + config.RegSize // offset of return value 1357 -> mem 1358 (Store (Load (OffPtr [c] (SP)) mem) x mem) 1359 && isConstZero(x) 1360 && mem.Op == OpStaticCall 1361 && isSameSym(mem.Aux, "runtime.newobject") 1362 && c == config.ctxt.FixedFrameSize() + config.RegSize // offset of return value 1363 -> mem 1364 (Store (OffPtr (Load (OffPtr [c] (SP)) mem)) x mem) 1365 && isConstZero(x) 1366 && mem.Op == OpStaticCall 1367 && isSameSym(mem.Aux, "runtime.newobject") 1368 && c == config.ctxt.FixedFrameSize() + config.RegSize // offset of return value 1369 -> mem 1370 // nil checks just need to rewrite to something useless. 1371 // they will be deadcode eliminated soon afterwards. 1372 (NilCheck (Load (OffPtr [c] (SP)) mem) mem) 1373 && mem.Op == OpStaticCall 1374 && isSameSym(mem.Aux, "runtime.newobject") 1375 && c == config.ctxt.FixedFrameSize() + config.RegSize // offset of return value 1376 && warnRule(fe.Debug_checknil() && v.Pos.Line() > 1, v, "removed nil check") 1377 -> (Invalid) 1378 (NilCheck (OffPtr (Load (OffPtr [c] (SP)) mem)) mem) 1379 && mem.Op == OpStaticCall 1380 && isSameSym(mem.Aux, "runtime.newobject") 1381 && c == config.ctxt.FixedFrameSize() + config.RegSize // offset of return value 1382 && warnRule(fe.Debug_checknil() && v.Pos.Line() > 1, v, "removed nil check") 1383 -> (Invalid) 1384 1385 // Address comparison shows up in type assertions. 1386 (EqPtr x x) -> (ConstBool [1]) 1387 (EqPtr (Addr {a} x) (Addr {b} x)) -> (ConstBool [b2i(a == b)]) 1388 1389 // De-virtualize interface calls into static calls. 1390 // Note that (ITab (IMake)) doesn't get 1391 // rewritten until after the first opt pass, 1392 // so this rule should trigger reliably. 1393 (InterCall [argsize] (Load (OffPtr [off] (ITab (IMake (Addr {itab} (SB)) _))) _) mem) && devirt(v, itab, off) != nil -> 1394 (StaticCall [argsize] {devirt(v, itab, off)} mem)