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1// Copyright 2022 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(Add(Ptr|64|32|16|8) ...) => (ADDV ...)
6(Add(32|64)F ...) => (ADD(F|D) ...)
7
8(Sub(Ptr|64|32|16|8) ...) => (SUBV ...)
9(Sub(32|64)F ...) => (SUB(F|D) ...)
10
11(Mul(64|32|16|8) ...) => (MULV ...)
12(Mul(32|64)F ...) => (MUL(F|D) ...)
13(Select0 (Mul64uhilo x y)) => (MULHVU x y)
14(Select1 (Mul64uhilo x y)) => (MULV x y)
15(Select0 (Mul64uover x y)) => (MULV x y)
16(Select1 (Mul64uover x y)) => (SGTU <typ.Bool> (MULHVU x y) (MOVVconst <typ.UInt64> [0]))
17
18(Hmul64 ...)  => (MULHV  ...)
19(Hmul64u ...) => (MULHVU ...)
20(Hmul32 x y)  => (SRAVconst (MULV (SignExt32to64 x) (SignExt32to64 y)) [32])
21(Hmul32u x y) => (SRLVconst (MULV (ZeroExt32to64 x) (ZeroExt32to64 y)) [32])
22
23(Div64 x y) => (DIVV x y)
24(Div64u ...) => (DIVVU ...)
25(Div32 x y) => (DIVV (SignExt32to64 x) (SignExt32to64 y))
26(Div32u x y) => (DIVVU (ZeroExt32to64 x) (ZeroExt32to64 y))
27(Div16 x y) => (DIVV (SignExt16to64 x) (SignExt16to64 y))
28(Div16u x y) => (DIVVU (ZeroExt16to64 x) (ZeroExt16to64 y))
29(Div8 x y) => (DIVV (SignExt8to64 x) (SignExt8to64 y))
30(Div8u x y) => (DIVVU (ZeroExt8to64 x) (ZeroExt8to64 y))
31(Div(32|64)F ...) => (DIV(F|D) ...)
32
33(Mod64 x y) => (REMV x y)
34(Mod64u ...) => (REMVU ...)
35(Mod32 x y) => (REMV (SignExt32to64 x) (SignExt32to64 y))
36(Mod32u x y) => (REMVU (ZeroExt32to64 x) (ZeroExt32to64 y))
37(Mod16 x y) => (REMV (SignExt16to64 x) (SignExt16to64 y))
38(Mod16u x y) => (REMVU (ZeroExt16to64 x) (ZeroExt16to64 y))
39(Mod8 x y) => (REMV (SignExt8to64 x) (SignExt8to64 y))
40(Mod8u x y) => (REMVU (ZeroExt8to64 x) (ZeroExt8to64 y))
41
42(Select0 <t> (Add64carry x y c)) => (ADDV (ADDV <t> x y) c)
43(Select1 <t> (Add64carry x y c)) =>
44	(OR (SGTU <t> x s:(ADDV <t> x y)) (SGTU <t> s (ADDV <t> s c)))
45
46(Select0 <t> (Sub64borrow x y c)) => (SUBV (SUBV <t> x y) c)
47(Select1 <t> (Sub64borrow x y c)) =>
48	(OR (SGTU <t> s:(SUBV <t> x y) x) (SGTU <t> (SUBV <t> s c) s))
49
50// (x + y) / 2 with x>=y => (x - y) / 2 + y
51(Avg64u <t> x y) => (ADDV (SRLVconst <t> (SUBV <t> x y) [1]) y)
52
53(And(64|32|16|8) ...) => (AND ...)
54(Or(64|32|16|8) ...) => (OR ...)
55(Xor(64|32|16|8) ...) => (XOR ...)
56
57// shifts
58// hardware instruction uses only the low 6 bits of the shift
59// we compare to 64 to ensure Go semantics for large shifts
60(Lsh64x64 <t> x y) => (MASKEQZ (SLLV <t> x                y)  (SGTU (MOVVconst <typ.UInt64> [64])                y))
61(Lsh64x32 <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt32to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt32to64 y)))
62(Lsh64x16 <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt16to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt16to64 y)))
63(Lsh64x8  <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt8to64  y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt8to64  y)))
64
65(Lsh32x64 <t> x y) => (MASKEQZ (SLLV <t> x                y)  (SGTU (MOVVconst <typ.UInt64> [64])                y))
66(Lsh32x32 <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt32to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt32to64 y)))
67(Lsh32x16 <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt16to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt16to64 y)))
68(Lsh32x8  <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt8to64  y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt8to64  y)))
69
70(Lsh16x64 <t> x y) => (MASKEQZ (SLLV <t> x                y)  (SGTU (MOVVconst <typ.UInt64> [64])                y))
71(Lsh16x32 <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt32to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt32to64 y)))
72(Lsh16x16 <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt16to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt16to64 y)))
73(Lsh16x8  <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt8to64  y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt8to64  y)))
74
75(Lsh8x64 <t> x y) => (MASKEQZ (SLLV <t> x                y)  (SGTU (MOVVconst <typ.UInt64> [64])                y))
76(Lsh8x32 <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt32to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt32to64 y)))
77(Lsh8x16 <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt16to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt16to64 y)))
78(Lsh8x8  <t> x y) => (MASKEQZ (SLLV <t> x (ZeroExt8to64  y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt8to64  y)))
79
80(Rsh64Ux64 <t> x y) => (MASKEQZ (SRLV <t> x                y)  (SGTU (MOVVconst <typ.UInt64> [64])                y))
81(Rsh64Ux32 <t> x y) => (MASKEQZ (SRLV <t> x (ZeroExt32to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt32to64 y)))
82(Rsh64Ux16 <t> x y) => (MASKEQZ (SRLV <t> x (ZeroExt16to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt16to64 y)))
83(Rsh64Ux8  <t> x y) => (MASKEQZ (SRLV <t> x (ZeroExt8to64  y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt8to64  y)))
84
85(Rsh32Ux64 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt32to64 x)                y)  (SGTU (MOVVconst <typ.UInt64> [64])                y))
86(Rsh32Ux32 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt32to64 x) (ZeroExt32to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt32to64 y)))
87(Rsh32Ux16 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt32to64 x) (ZeroExt16to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt16to64 y)))
88(Rsh32Ux8  <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt32to64 x) (ZeroExt8to64  y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt8to64  y)))
89
90(Rsh16Ux64 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt16to64 x)                y)  (SGTU (MOVVconst <typ.UInt64> [64])                y))
91(Rsh16Ux32 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt16to64 x) (ZeroExt32to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt32to64 y)))
92(Rsh16Ux16 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt16to64 x) (ZeroExt16to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt16to64 y)))
93(Rsh16Ux8  <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt16to64 x) (ZeroExt8to64  y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt8to64  y)))
94
95(Rsh8Ux64 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt8to64 x)                y)  (SGTU (MOVVconst <typ.UInt64> [64])                y))
96(Rsh8Ux32 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt8to64 x) (ZeroExt32to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt32to64 y)))
97(Rsh8Ux16 <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt8to64 x) (ZeroExt16to64 y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt16to64 y)))
98(Rsh8Ux8  <t> x y) => (MASKEQZ (SRLV <t> (ZeroExt8to64 x) (ZeroExt8to64  y)) (SGTU (MOVVconst <typ.UInt64> [64]) (ZeroExt8to64  y)))
99
100(Rsh64x64 <t> x y) => (SRAV x (OR <t> (NEGV <t> (SGTU y (MOVVconst <typ.UInt64> [63]))) y))
101(Rsh64x32 <t> x y) => (SRAV x (OR <t> (NEGV <t> (SGTU (ZeroExt32to64 y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt32to64 y)))
102(Rsh64x16 <t> x y) => (SRAV x (OR <t> (NEGV <t> (SGTU (ZeroExt16to64 y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt16to64 y)))
103(Rsh64x8  <t> x y) => (SRAV x (OR <t> (NEGV <t> (SGTU (ZeroExt8to64  y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt8to64  y)))
104
105(Rsh32x64 <t> x y) => (SRAV (SignExt32to64 x) (OR <t> (NEGV <t> (SGTU y (MOVVconst <typ.UInt64> [63]))) y))
106(Rsh32x32 <t> x y) => (SRAV (SignExt32to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt32to64 y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt32to64 y)))
107(Rsh32x16 <t> x y) => (SRAV (SignExt32to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt16to64 y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt16to64 y)))
108(Rsh32x8  <t> x y) => (SRAV (SignExt32to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt8to64  y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt8to64  y)))
109
110(Rsh16x64 <t> x y) => (SRAV (SignExt16to64 x) (OR <t> (NEGV <t> (SGTU y (MOVVconst <typ.UInt64> [63]))) y))
111(Rsh16x32 <t> x y) => (SRAV (SignExt16to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt32to64 y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt32to64 y)))
112(Rsh16x16 <t> x y) => (SRAV (SignExt16to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt16to64 y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt16to64 y)))
113(Rsh16x8  <t> x y) => (SRAV (SignExt16to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt8to64  y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt8to64  y)))
114
115(Rsh8x64 <t> x y) => (SRAV (SignExt8to64 x) (OR <t> (NEGV <t> (SGTU y (MOVVconst <typ.UInt64> [63]))) y))
116(Rsh8x32 <t> x y) => (SRAV (SignExt8to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt32to64 y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt32to64 y)))
117(Rsh8x16 <t> x y) => (SRAV (SignExt8to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt16to64 y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt16to64 y)))
118(Rsh8x8  <t> x y) => (SRAV (SignExt8to64 x) (OR <t> (NEGV <t> (SGTU (ZeroExt8to64  y) (MOVVconst <typ.UInt64> [63]))) (ZeroExt8to64  y)))
119
120// rotates
121(RotateLeft8 <t> x (MOVVconst [c])) => (Or8 (Lsh8x64 <t> x (MOVVconst [c&7])) (Rsh8Ux64 <t> x (MOVVconst [-c&7])))
122(RotateLeft16 <t> x (MOVVconst [c])) => (Or16 (Lsh16x64 <t> x (MOVVconst [c&15])) (Rsh16Ux64 <t> x (MOVVconst [-c&15])))
123(RotateLeft32 x y) => (ROTR  x (NEGV <y.Type> y))
124(RotateLeft64 x y) => (ROTRV x (NEGV <y.Type> y))
125
126// unary ops
127(Neg(64|32|16|8) ...) => (NEGV ...)
128(Neg(32|64)F ...) => (NEG(F|D) ...)
129
130(Com(64|32|16|8) x) => (NOR (MOVVconst [0]) x)
131
132(Sqrt ...) => (SQRTD ...)
133(Sqrt32 ...) => (SQRTF ...)
134
135// boolean ops -- booleans are represented with 0=false, 1=true
136(AndB ...) => (AND ...)
137(OrB ...) => (OR ...)
138(EqB x y) => (XOR (MOVVconst [1]) (XOR <typ.Bool> x y))
139(NeqB ...) => (XOR ...)
140(Not x) => (XORconst [1] x)
141
142// constants
143(Const(64|32|16|8) [val]) => (MOVVconst [int64(val)])
144(Const(32|64)F [val]) => (MOV(F|D)const [float64(val)])
145(ConstNil) => (MOVVconst [0])
146(ConstBool [t]) => (MOVVconst [int64(b2i(t))])
147
148(Slicemask <t> x) => (SRAVconst (NEGV <t> x) [63])
149
150// truncations
151// Because we ignore high parts of registers, truncates are just copies.
152(Trunc16to8 ...) => (Copy ...)
153(Trunc32to8 ...) => (Copy ...)
154(Trunc32to16 ...) => (Copy ...)
155(Trunc64to8 ...) => (Copy ...)
156(Trunc64to16 ...) => (Copy ...)
157(Trunc64to32 ...) => (Copy ...)
158
159// Zero-/Sign-extensions
160(ZeroExt8to16 ...) => (MOVBUreg ...)
161(ZeroExt8to32 ...) => (MOVBUreg ...)
162(ZeroExt16to32 ...) => (MOVHUreg ...)
163(ZeroExt8to64 ...) => (MOVBUreg ...)
164(ZeroExt16to64 ...) => (MOVHUreg ...)
165(ZeroExt32to64 ...) => (MOVWUreg ...)
166
167(SignExt8to16 ...) => (MOVBreg ...)
168(SignExt8to32 ...) => (MOVBreg ...)
169(SignExt16to32 ...) => (MOVHreg ...)
170(SignExt8to64 ...) => (MOVBreg ...)
171(SignExt16to64 ...) => (MOVHreg ...)
172(SignExt32to64 ...) => (MOVWreg ...)
173
174// float <=> int conversion
175(Cvt32to32F ...) => (MOVWF ...)
176(Cvt32to64F ...) => (MOVWD ...)
177(Cvt64to32F ...) => (MOVVF ...)
178(Cvt64to64F ...) => (MOVVD ...)
179(Cvt32Fto32 ...) => (TRUNCFW ...)
180(Cvt64Fto32 ...) => (TRUNCDW ...)
181(Cvt32Fto64 ...) => (TRUNCFV ...)
182(Cvt64Fto64 ...) => (TRUNCDV ...)
183(Cvt32Fto64F ...) => (MOVFD ...)
184(Cvt64Fto32F ...) => (MOVDF ...)
185
186(CvtBoolToUint8 ...) => (Copy ...)
187
188(Round(32|64)F ...) => (Copy ...)
189
190// comparisons
191(Eq8 x y)  => (SGTU (MOVVconst [1]) (XOR (ZeroExt8to64 x) (ZeroExt8to64 y)))
192(Eq16 x y) => (SGTU (MOVVconst [1]) (XOR (ZeroExt16to64 x) (ZeroExt16to64 y)))
193(Eq32 x y) => (SGTU (MOVVconst [1]) (XOR (ZeroExt32to64 x) (ZeroExt32to64 y)))
194(Eq64 x y) => (SGTU (MOVVconst [1]) (XOR x y))
195(EqPtr x y) => (SGTU (MOVVconst [1]) (XOR x y))
196(Eq(32|64)F x y) => (FPFlagTrue (CMPEQ(F|D) x y))
197
198(Neq8 x y)  => (SGTU (XOR (ZeroExt8to64 x) (ZeroExt8to64 y)) (MOVVconst [0]))
199(Neq16 x y) => (SGTU (XOR (ZeroExt16to32 x) (ZeroExt16to64 y)) (MOVVconst [0]))
200(Neq32 x y) => (SGTU (XOR (ZeroExt32to64 x) (ZeroExt32to64 y)) (MOVVconst [0]))
201(Neq64 x y) => (SGTU (XOR x y) (MOVVconst [0]))
202(NeqPtr x y) => (SGTU (XOR x y) (MOVVconst [0]))
203(Neq(32|64)F x y) => (FPFlagFalse (CMPEQ(F|D) x y))
204
205(Less8 x y)  => (SGT (SignExt8to64 y) (SignExt8to64 x))
206(Less16 x y) => (SGT (SignExt16to64 y) (SignExt16to64 x))
207(Less32 x y) => (SGT (SignExt32to64 y) (SignExt32to64 x))
208(Less64 x y) => (SGT y x)
209(Less(32|64)F x y) => (FPFlagTrue (CMPGT(F|D) y x)) // reverse operands to work around NaN
210
211(Less8U x y)  => (SGTU (ZeroExt8to64 y) (ZeroExt8to64 x))
212(Less16U x y) => (SGTU (ZeroExt16to64 y) (ZeroExt16to64 x))
213(Less32U x y) => (SGTU (ZeroExt32to64 y) (ZeroExt32to64 x))
214(Less64U x y) => (SGTU y x)
215
216(Leq8 x y)  => (XOR (MOVVconst [1]) (SGT (SignExt8to64 x) (SignExt8to64 y)))
217(Leq16 x y) => (XOR (MOVVconst [1]) (SGT (SignExt16to64 x) (SignExt16to64 y)))
218(Leq32 x y) => (XOR (MOVVconst [1]) (SGT (SignExt32to64 x) (SignExt32to64 y)))
219(Leq64 x y) => (XOR (MOVVconst [1]) (SGT x y))
220(Leq(32|64)F x y) => (FPFlagTrue (CMPGE(F|D) y x)) // reverse operands to work around NaN
221
222(Leq8U x y)  => (XOR (MOVVconst [1]) (SGTU (ZeroExt8to64 x) (ZeroExt8to64 y)))
223(Leq16U x y) => (XOR (MOVVconst [1]) (SGTU (ZeroExt16to64 x) (ZeroExt16to64 y)))
224(Leq32U x y) => (XOR (MOVVconst [1]) (SGTU (ZeroExt32to64 x) (ZeroExt32to64 y)))
225(Leq64U x y) => (XOR (MOVVconst [1]) (SGTU x y))
226
227(OffPtr [off] ptr:(SP)) => (MOVVaddr [int32(off)] ptr)
228(OffPtr [off] ptr) => (ADDVconst [off] ptr)
229
230(Addr {sym} base) => (MOVVaddr {sym} base)
231(LocalAddr <t> {sym} base mem) && t.Elem().HasPointers() => (MOVVaddr {sym} (SPanchored base mem))
232(LocalAddr <t> {sym} base _)  && !t.Elem().HasPointers() => (MOVVaddr {sym} base)
233
234// loads
235(Load <t> ptr mem) && t.IsBoolean() => (MOVBUload ptr mem)
236(Load <t> ptr mem) && (is8BitInt(t)  &&  t.IsSigned()) => (MOVBload ptr mem)
237(Load <t> ptr mem) && (is8BitInt(t)  && !t.IsSigned()) => (MOVBUload ptr mem)
238(Load <t> ptr mem) && (is16BitInt(t) &&  t.IsSigned()) => (MOVHload ptr mem)
239(Load <t> ptr mem) && (is16BitInt(t) && !t.IsSigned()) => (MOVHUload ptr mem)
240(Load <t> ptr mem) && (is32BitInt(t) &&  t.IsSigned()) => (MOVWload ptr mem)
241(Load <t> ptr mem) && (is32BitInt(t) && !t.IsSigned()) => (MOVWUload ptr mem)
242(Load <t> ptr mem) && (is64BitInt(t) || isPtr(t)) => (MOVVload ptr mem)
243(Load <t> ptr mem) && is32BitFloat(t) => (MOVFload ptr mem)
244(Load <t> ptr mem) && is64BitFloat(t) => (MOVDload ptr mem)
245
246// stores
247(Store {t} ptr val mem) && t.Size() == 1 => (MOVBstore ptr val mem)
248(Store {t} ptr val mem) && t.Size() == 2 => (MOVHstore ptr val mem)
249(Store {t} ptr val mem) && t.Size() == 4 && !t.IsFloat() => (MOVWstore ptr val mem)
250(Store {t} ptr val mem) && t.Size() == 8 && !t.IsFloat() => (MOVVstore ptr val mem)
251(Store {t} ptr val mem) && t.Size() == 4 &&  t.IsFloat() => (MOVFstore ptr val mem)
252(Store {t} ptr val mem) && t.Size() == 8 &&  t.IsFloat() => (MOVDstore ptr val mem)
253
254// zeroing
255(Zero [0] _ mem) => mem
256(Zero [1] ptr mem) => (MOVBstore ptr (MOVVconst [0]) mem)
257(Zero [2] {t} ptr mem) && t.Alignment()%2 == 0 =>
258	(MOVHstore ptr (MOVVconst [0]) mem)
259(Zero [2] ptr mem) =>
260	(MOVBstore [1] ptr (MOVVconst [0])
261		(MOVBstore [0] ptr (MOVVconst [0]) mem))
262(Zero [4] {t} ptr mem) && t.Alignment()%4 == 0 =>
263	(MOVWstore ptr (MOVVconst [0]) mem)
264(Zero [4] {t} ptr mem) && t.Alignment()%2 == 0 =>
265	(MOVHstore [2] ptr (MOVVconst [0])
266		(MOVHstore [0] ptr (MOVVconst [0]) mem))
267(Zero [4] ptr mem) =>
268	(MOVBstore [3] ptr (MOVVconst [0])
269		(MOVBstore [2] ptr (MOVVconst [0])
270			(MOVBstore [1] ptr (MOVVconst [0])
271				(MOVBstore [0] ptr (MOVVconst [0]) mem))))
272(Zero [8] {t} ptr mem) && t.Alignment()%8 == 0 =>
273	(MOVVstore ptr (MOVVconst [0]) mem)
274(Zero [8] {t} ptr mem) && t.Alignment()%4 == 0 =>
275	(MOVWstore [4] ptr (MOVVconst [0])
276		(MOVWstore [0] ptr (MOVVconst [0]) mem))
277(Zero [8] {t} ptr mem) && t.Alignment()%2 == 0 =>
278	(MOVHstore [6] ptr (MOVVconst [0])
279		(MOVHstore [4] ptr (MOVVconst [0])
280			(MOVHstore [2] ptr (MOVVconst [0])
281				(MOVHstore [0] ptr (MOVVconst [0]) mem))))
282
283(Zero [3] ptr mem) =>
284	(MOVBstore [2] ptr (MOVVconst [0])
285		(MOVBstore [1] ptr (MOVVconst [0])
286			(MOVBstore [0] ptr (MOVVconst [0]) mem)))
287(Zero [6] {t} ptr mem) && t.Alignment()%2 == 0 =>
288	(MOVHstore [4] ptr (MOVVconst [0])
289		(MOVHstore [2] ptr (MOVVconst [0])
290			(MOVHstore [0] ptr (MOVVconst [0]) mem)))
291(Zero [12] {t} ptr mem) && t.Alignment()%4 == 0 =>
292	(MOVWstore [8] ptr (MOVVconst [0])
293		(MOVWstore [4] ptr (MOVVconst [0])
294			(MOVWstore [0] ptr (MOVVconst [0]) mem)))
295(Zero [16] {t} ptr mem) && t.Alignment()%8 == 0 =>
296	(MOVVstore [8] ptr (MOVVconst [0])
297		(MOVVstore [0] ptr (MOVVconst [0]) mem))
298(Zero [24] {t} ptr mem) && t.Alignment()%8 == 0 =>
299	(MOVVstore [16] ptr (MOVVconst [0])
300		(MOVVstore [8] ptr (MOVVconst [0])
301			(MOVVstore [0] ptr (MOVVconst [0]) mem)))
302
303// medium zeroing uses a duff device
304// 8, and 128 are magic constants, see runtime/mkduff.go
305(Zero [s] {t} ptr mem)
306	&& s%8 == 0 && s > 24 && s <= 8*128
307	&& t.Alignment()%8 == 0 && !config.noDuffDevice =>
308	(DUFFZERO [8 * (128 - s/8)] ptr mem)
309
310// large or unaligned zeroing uses a loop
311(Zero [s] {t} ptr mem)
312	&& (s > 8*128 || config.noDuffDevice) || t.Alignment()%8 != 0 =>
313	(LoweredZero [t.Alignment()]
314		ptr
315		(ADDVconst <ptr.Type> ptr [s-moveSize(t.Alignment(), config)])
316		mem)
317
318// moves
319(Move [0] _ _ mem) => mem
320(Move [1] dst src mem) => (MOVBstore dst (MOVBload src mem) mem)
321(Move [2] {t} dst src mem) && t.Alignment()%2 == 0 =>
322	(MOVHstore dst (MOVHload src mem) mem)
323(Move [2] dst src mem) =>
324	(MOVBstore [1] dst (MOVBload [1] src mem)
325		(MOVBstore dst (MOVBload src mem) mem))
326(Move [4] {t} dst src mem) && t.Alignment()%4 == 0 =>
327	(MOVWstore dst (MOVWload src mem) mem)
328(Move [4] {t} dst src mem) && t.Alignment()%2 == 0 =>
329	(MOVHstore [2] dst (MOVHload [2] src mem)
330		(MOVHstore dst (MOVHload src mem) mem))
331(Move [4] dst src mem) =>
332	(MOVBstore [3] dst (MOVBload [3] src mem)
333		(MOVBstore [2] dst (MOVBload [2] src mem)
334			(MOVBstore [1] dst (MOVBload [1] src mem)
335				(MOVBstore dst (MOVBload src mem) mem))))
336(Move [8] {t} dst src mem) && t.Alignment()%8 == 0 =>
337	(MOVVstore dst (MOVVload src mem) mem)
338(Move [8] {t} dst src mem) && t.Alignment()%4 == 0 =>
339	(MOVWstore [4] dst (MOVWload [4] src mem)
340		(MOVWstore dst (MOVWload src mem) mem))
341(Move [8] {t} dst src mem) && t.Alignment()%2 == 0 =>
342	(MOVHstore [6] dst (MOVHload [6] src mem)
343		(MOVHstore [4] dst (MOVHload [4] src mem)
344			(MOVHstore [2] dst (MOVHload [2] src mem)
345				(MOVHstore dst (MOVHload src mem) mem))))
346
347(Move [3] dst src mem) =>
348	(MOVBstore [2] dst (MOVBload [2] src mem)
349		(MOVBstore [1] dst (MOVBload [1] src mem)
350			(MOVBstore dst (MOVBload src mem) mem)))
351(Move [6] {t} dst src mem) && t.Alignment()%2 == 0 =>
352	(MOVHstore [4] dst (MOVHload [4] src mem)
353		(MOVHstore [2] dst (MOVHload [2] src mem)
354			(MOVHstore dst (MOVHload src mem) mem)))
355(Move [12] {t} dst src mem) && t.Alignment()%4 == 0 =>
356	(MOVWstore [8] dst (MOVWload [8] src mem)
357		(MOVWstore [4] dst (MOVWload [4] src mem)
358			(MOVWstore dst (MOVWload src mem) mem)))
359(Move [16] {t} dst src mem) && t.Alignment()%8 == 0 =>
360	(MOVVstore [8] dst (MOVVload [8] src mem)
361		(MOVVstore dst (MOVVload src mem) mem))
362(Move [24] {t} dst src mem) && t.Alignment()%8 == 0 =>
363	(MOVVstore [16] dst (MOVVload [16] src mem)
364		(MOVVstore [8] dst (MOVVload [8] src mem)
365			(MOVVstore dst (MOVVload src mem) mem)))
366
367// medium move uses a duff device
368(Move [s] {t} dst src mem)
369	&& s%8 == 0 && s >= 24 && s <= 8*128 && t.Alignment()%8 == 0
370	&& !config.noDuffDevice && logLargeCopy(v, s)  =>
371	(DUFFCOPY [16 * (128 - s/8)] dst src mem)
372// 16 and 128 are magic constants.  16 is the number of bytes to encode:
373//	MOVV	(R1), R23
374//	ADDV	$8, R1
375//	MOVV	R23, (R2)
376//	ADDV	$8, R2
377// and 128 is the number of such blocks. See runtime/duff_mips64.s:duffcopy.
378
379// large or unaligned move uses a loop
380(Move [s] {t} dst src mem)
381	&& s > 24 && logLargeCopy(v, s) || t.Alignment()%8 != 0 =>
382	(LoweredMove [t.Alignment()]
383		dst
384		src
385		(ADDVconst <src.Type> src [s-moveSize(t.Alignment(), config)])
386		mem)
387
388// calls
389(StaticCall ...) => (CALLstatic ...)
390(ClosureCall ...) => (CALLclosure ...)
391(InterCall ...) => (CALLinter ...)
392(TailCall ...) => (CALLtail ...)
393
394// atomic intrinsics
395(AtomicLoad(8|32|64)   ...) => (LoweredAtomicLoad(8|32|64)  ...)
396(AtomicLoadPtr ...) => (LoweredAtomicLoad64 ...)
397
398(AtomicStore(8|32|64) ...) => (LoweredAtomicStore(8|32|64)  ...)
399(AtomicStorePtrNoWB ...) => (LoweredAtomicStore64 ...)
400
401(AtomicExchange(32|64) ...) => (LoweredAtomicExchange(32|64) ...)
402
403(AtomicAdd(32|64) ...) => (LoweredAtomicAdd(32|64) ...)
404
405(AtomicCompareAndSwap32 ptr old new mem) => (LoweredAtomicCas32 ptr (SignExt32to64 old) new mem)
406(AtomicCompareAndSwap64 ...) => (LoweredAtomicCas64 ...)
407
408// checks
409(NilCheck ...) => (LoweredNilCheck ...)
410(IsNonNil ptr) => (SGTU ptr (MOVVconst [0]))
411(IsInBounds idx len) => (SGTU len idx)
412(IsSliceInBounds idx len) => (XOR (MOVVconst [1]) (SGTU idx len))
413
414// pseudo-ops
415(GetClosurePtr ...) => (LoweredGetClosurePtr ...)
416(GetCallerSP ...) => (LoweredGetCallerSP ...)
417(GetCallerPC ...) => (LoweredGetCallerPC ...)
418
419(If cond yes no) => (NE (MOVBUreg <typ.UInt64> cond) yes no)
420
421// Write barrier.
422(WB ...) => (LoweredWB ...)
423
424(PanicBounds [kind] x y mem) && boundsABI(kind) == 0 => (LoweredPanicBoundsA [kind] x y mem)
425(PanicBounds [kind] x y mem) && boundsABI(kind) == 1 => (LoweredPanicBoundsB [kind] x y mem)
426(PanicBounds [kind] x y mem) && boundsABI(kind) == 2 => (LoweredPanicBoundsC [kind] x y mem)
427
428(CondSelect <t> x y cond) => (OR (MASKEQZ <t> x cond) (MASKNEZ <t> y cond))
429
430// Optimizations
431
432// Absorb boolean tests into block
433(NE (FPFlagTrue cmp) yes no) => (FPT cmp yes no)
434(NE (FPFlagFalse cmp) yes no) => (FPF cmp yes no)
435(EQ (FPFlagTrue cmp) yes no) => (FPF cmp yes no)
436(EQ (FPFlagFalse cmp) yes no) => (FPT cmp yes no)
437(NE (XORconst [1] cmp:(SGT _ _)) yes no) => (EQ cmp yes no)
438(NE (XORconst [1] cmp:(SGTU _ _)) yes no) => (EQ cmp yes no)
439(NE (XORconst [1] cmp:(SGTconst _)) yes no) => (EQ cmp yes no)
440(NE (XORconst [1] cmp:(SGTUconst _)) yes no) => (EQ cmp yes no)
441(EQ (XORconst [1] cmp:(SGT _ _)) yes no) => (NE cmp yes no)
442(EQ (XORconst [1] cmp:(SGTU _ _)) yes no) => (NE cmp yes no)
443(EQ (XORconst [1] cmp:(SGTconst _)) yes no) => (NE cmp yes no)
444(EQ (XORconst [1] cmp:(SGTUconst _)) yes no) => (NE cmp yes no)
445(NE (SGTUconst [1] x) yes no) => (EQ x yes no)
446(EQ (SGTUconst [1] x) yes no) => (NE x yes no)
447(NE (SGTU x (MOVVconst [0])) yes no) => (NE x yes no)
448(EQ (SGTU x (MOVVconst [0])) yes no) => (EQ x yes no)
449(NE (SGTconst [0] x) yes no) => (LTZ x yes no)
450(EQ (SGTconst [0] x) yes no) => (GEZ x yes no)
451(NE (SGT x (MOVVconst [0])) yes no) => (GTZ x yes no)
452(EQ (SGT x (MOVVconst [0])) yes no) => (LEZ x yes no)
453(MOVBUreg x:((SGT|SGTU) _ _)) => x
454
455// fold offset into address
456(ADDVconst [off1] (MOVVaddr [off2] {sym} ptr)) && is32Bit(off1+int64(off2)) => (MOVVaddr [int32(off1)+int32(off2)] {sym} ptr)
457
458// fold address into load/store
459// Do not fold global variable access in -dynlink mode, where it will be rewritten
460// to use the GOT via REGTMP, which currently cannot handle large offset.
461(MOV(B|BU|H|HU|W|WU|V|F|D)load [off1] {sym} (ADDVconst [off2] ptr) mem) && is32Bit(int64(off1)+off2)
462	&& (ptr.Op != OpSB || !config.ctxt.Flag_dynlink) =>
463	(MOV(B|BU|H|HU|W|WU|V|F|D)load [off1+int32(off2)] {sym} ptr mem)
464
465(MOV(B|H|W|V|F|D)store [off1] {sym} (ADDVconst [off2] ptr) val mem) && is32Bit(int64(off1)+off2)
466	&& (ptr.Op != OpSB || !config.ctxt.Flag_dynlink) =>
467	(MOV(B|H|W|V|F|D)store [off1+int32(off2)] {sym} ptr val mem)
468
469(MOV(B|H|W|V)storezero [off1] {sym} (ADDVconst [off2] ptr) mem) && is32Bit(int64(off1)+off2)
470	&& (ptr.Op != OpSB || !config.ctxt.Flag_dynlink) =>
471	(MOV(B|H|W|V)storezero [off1+int32(off2)] {sym} ptr mem)
472
473(MOV(B|BU|H|HU|W|WU|V|F|D)load [off1] {sym1} (MOVVaddr [off2] {sym2} ptr) mem) && canMergeSym(sym1,sym2)
474	&& is32Bit(int64(off1)+int64(off2)) && (ptr.Op != OpSB || !config.ctxt.Flag_dynlink) =>
475	(MOV(B|BU|H|HU|W|WU|V|F|D)load [off1+int32(off2)] {mergeSym(sym1,sym2)} ptr mem)
476
477(MOV(B|H|W|V|F|D)store [off1] {sym1} (MOVVaddr [off2] {sym2} ptr) val mem) && canMergeSym(sym1,sym2)
478	&& is32Bit(int64(off1)+int64(off2)) && (ptr.Op != OpSB || !config.ctxt.Flag_dynlink) =>
479	(MOV(B|H|W|V|F|D)store [off1+int32(off2)] {mergeSym(sym1,sym2)} ptr val mem)
480
481(MOV(B|H|W|V)storezero [off1] {sym1} (MOVVaddr [off2] {sym2} ptr) mem) && canMergeSym(sym1,sym2)
482	&& is32Bit(int64(off1)+int64(off2)) && (ptr.Op != OpSB || !config.ctxt.Flag_dynlink) =>
483	(MOV(B|H|W|V)storezero [off1+int32(off2)] {mergeSym(sym1,sym2)} ptr mem)
484
485(LoweredAtomicStore(32|64) ptr (MOVVconst [0]) mem) => (LoweredAtomicStorezero(32|64) ptr mem)
486(LoweredAtomicAdd32 ptr (MOVVconst [c]) mem) && is32Bit(c) => (LoweredAtomicAddconst32 [int32(c)] ptr mem)
487(LoweredAtomicAdd64 ptr (MOVVconst [c]) mem) && is32Bit(c) => (LoweredAtomicAddconst64 [c] ptr mem)
488
489// don't extend after proper load
490(MOVBreg x:(MOVBload _ _)) => (MOVVreg x)
491(MOVBUreg x:(MOVBUload _ _)) => (MOVVreg x)
492(MOVHreg x:(MOVBload _ _)) => (MOVVreg x)
493(MOVHreg x:(MOVBUload _ _)) => (MOVVreg x)
494(MOVHreg x:(MOVHload _ _)) => (MOVVreg x)
495(MOVHUreg x:(MOVBUload _ _)) => (MOVVreg x)
496(MOVHUreg x:(MOVHUload _ _)) => (MOVVreg x)
497(MOVWreg x:(MOVBload _ _)) => (MOVVreg x)
498(MOVWreg x:(MOVBUload _ _)) => (MOVVreg x)
499(MOVWreg x:(MOVHload _ _)) => (MOVVreg x)
500(MOVWreg x:(MOVHUload _ _)) => (MOVVreg x)
501(MOVWreg x:(MOVWload _ _)) => (MOVVreg x)
502(MOVWUreg x:(MOVBUload _ _)) => (MOVVreg x)
503(MOVWUreg x:(MOVHUload _ _)) => (MOVVreg x)
504(MOVWUreg x:(MOVWUload _ _)) => (MOVVreg x)
505
506// fold double extensions
507(MOVBreg x:(MOVBreg _)) => (MOVVreg x)
508(MOVBUreg x:(MOVBUreg _)) => (MOVVreg x)
509(MOVHreg x:(MOVBreg _)) => (MOVVreg x)
510(MOVHreg x:(MOVBUreg _)) => (MOVVreg x)
511(MOVHreg x:(MOVHreg _)) => (MOVVreg x)
512(MOVHUreg x:(MOVBUreg _)) => (MOVVreg x)
513(MOVHUreg x:(MOVHUreg _)) => (MOVVreg x)
514(MOVWreg x:(MOVBreg _)) => (MOVVreg x)
515(MOVWreg x:(MOVBUreg _)) => (MOVVreg x)
516(MOVWreg x:(MOVHreg _)) => (MOVVreg x)
517(MOVWreg x:(MOVWreg _)) => (MOVVreg x)
518(MOVWUreg x:(MOVBUreg _)) => (MOVVreg x)
519(MOVWUreg x:(MOVHUreg _)) => (MOVVreg x)
520(MOVWUreg x:(MOVWUreg _)) => (MOVVreg x)
521
522// don't extend before store
523(MOVBstore [off] {sym} ptr (MOVBreg x) mem) => (MOVBstore [off] {sym} ptr x mem)
524(MOVBstore [off] {sym} ptr (MOVBUreg x) mem) => (MOVBstore [off] {sym} ptr x mem)
525(MOVBstore [off] {sym} ptr (MOVHreg x) mem) => (MOVBstore [off] {sym} ptr x mem)
526(MOVBstore [off] {sym} ptr (MOVHUreg x) mem) => (MOVBstore [off] {sym} ptr x mem)
527(MOVBstore [off] {sym} ptr (MOVWreg x) mem) => (MOVBstore [off] {sym} ptr x mem)
528(MOVBstore [off] {sym} ptr (MOVWUreg x) mem) => (MOVBstore [off] {sym} ptr x mem)
529(MOVHstore [off] {sym} ptr (MOVHreg x) mem) => (MOVHstore [off] {sym} ptr x mem)
530(MOVHstore [off] {sym} ptr (MOVHUreg x) mem) => (MOVHstore [off] {sym} ptr x mem)
531(MOVHstore [off] {sym} ptr (MOVWreg x) mem) => (MOVHstore [off] {sym} ptr x mem)
532(MOVHstore [off] {sym} ptr (MOVWUreg x) mem) => (MOVHstore [off] {sym} ptr x mem)
533(MOVWstore [off] {sym} ptr (MOVWreg x) mem) => (MOVWstore [off] {sym} ptr x mem)
534(MOVWstore [off] {sym} ptr (MOVWUreg x) mem) => (MOVWstore [off] {sym} ptr x mem)
535
536// if a register move has only 1 use, just use the same register without emitting instruction
537// MOVVnop doesn't emit instruction, only for ensuring the type.
538(MOVVreg x) && x.Uses == 1 => (MOVVnop x)
539
540// fold constant into arithmetic ops
541(ADDV x (MOVVconst <t> [c])) && is32Bit(c) && !t.IsPtr() => (ADDVconst [c] x)
542(SUBV x (MOVVconst [c])) && is32Bit(c) => (SUBVconst [c] x)
543(AND x (MOVVconst [c])) && is32Bit(c) => (ANDconst [c] x)
544(OR  x (MOVVconst [c])) && is32Bit(c) => (ORconst  [c] x)
545(XOR x (MOVVconst [c])) && is32Bit(c) => (XORconst [c] x)
546(NOR x (MOVVconst [c])) && is32Bit(c) => (NORconst [c] x)
547
548(SLLV _ (MOVVconst [c])) && uint64(c)>=64 => (MOVVconst [0])
549(SRLV _ (MOVVconst [c])) && uint64(c)>=64 => (MOVVconst [0])
550(SRAV x (MOVVconst [c])) && uint64(c)>=64 => (SRAVconst x [63])
551(SLLV x (MOVVconst [c])) => (SLLVconst x [c])
552(SRLV x (MOVVconst [c])) => (SRLVconst x [c])
553(SRAV x (MOVVconst [c])) => (SRAVconst x [c])
554(ROTR x (MOVVconst [c]))  => (ROTRconst x [c&31])
555(ROTRV x (MOVVconst [c])) => (ROTRVconst x [c&63])
556
557(SGT  (MOVVconst [c]) x) && is32Bit(c) => (SGTconst  [c] x)
558(SGTU (MOVVconst [c]) x) && is32Bit(c) => (SGTUconst [c] x)
559
560// mul by constant
561(MULV x (MOVVconst [-1])) => (NEGV x)
562(MULV _ (MOVVconst [0])) => (MOVVconst [0])
563(MULV x (MOVVconst [1])) => x
564(MULV x (MOVVconst [c])) && isPowerOfTwo64(c) => (SLLVconst [log64(c)] x)
565
566// div by constant
567(DIVVU x (MOVVconst [1])) => x
568(DIVVU x (MOVVconst [c])) && isPowerOfTwo64(c) => (SRLVconst [log64(c)] x)
569(REMVU _ (MOVVconst [1])) => (MOVVconst [0])                       // mod
570(REMVU x (MOVVconst [c])) && isPowerOfTwo64(c) => (ANDconst [c-1] x) // mod
571
572// generic simplifications
573(ADDV x (NEGV y)) => (SUBV x y)
574(SUBV x x) => (MOVVconst [0])
575(SUBV (MOVVconst [0]) x) => (NEGV x)
576(AND x x) => x
577(OR  x x) => x
578(XOR x x) => (MOVVconst [0])
579
580// remove redundant *const ops
581(ADDVconst [0]  x) => x
582(SUBVconst [0]  x) => x
583(ANDconst [0]  _) => (MOVVconst [0])
584(ANDconst [-1] x) => x
585(ORconst  [0]  x) => x
586(ORconst  [-1] _) => (MOVVconst [-1])
587(XORconst [0]  x) => x
588(XORconst [-1] x) => (NORconst [0] x)
589(MASKEQZ (MOVVconst [0]) cond) => (MOVVconst [0])
590(MASKNEZ (MOVVconst [0]) cond) => (MOVVconst [0])
591(MASKEQZ x (MOVVconst [c])) && c == 0 => (MOVVconst [0])
592(MASKEQZ x (MOVVconst [c])) && c != 0 => x
593
594// generic constant folding
595(ADDVconst [c] (MOVVconst [d]))  => (MOVVconst [c+d])
596(ADDVconst [c] (ADDVconst [d] x)) && is32Bit(c+d) => (ADDVconst [c+d] x)
597(ADDVconst [c] (SUBVconst [d] x)) && is32Bit(c-d) => (ADDVconst [c-d] x)
598(SUBVconst [c] (MOVVconst [d]))  => (MOVVconst [d-c])
599(SUBVconst [c] (SUBVconst [d] x)) && is32Bit(-c-d) => (ADDVconst [-c-d] x)
600(SUBVconst [c] (ADDVconst [d] x)) && is32Bit(-c+d) => (ADDVconst [-c+d] x)
601(SLLVconst [c] (MOVVconst [d]))  => (MOVVconst [d<<uint64(c)])
602(SRLVconst [c] (MOVVconst [d]))  => (MOVVconst [int64(uint64(d)>>uint64(c))])
603(SRAVconst [c] (MOVVconst [d]))  => (MOVVconst [d>>uint64(c)])
604(MULV (MOVVconst [c]) (MOVVconst [d])) => (MOVVconst [c*d])
605(DIVV  (MOVVconst [c]) (MOVVconst [d])) && d != 0 => (MOVVconst [c/d])
606(DIVVU (MOVVconst [c]) (MOVVconst [d])) && d != 0 => (MOVVconst [int64(uint64(c)/uint64(d))])
607(REMV  (MOVVconst [c]) (MOVVconst [d])) && d != 0 => (MOVVconst [c%d])   // mod
608(REMVU (MOVVconst [c]) (MOVVconst [d])) && d != 0 => (MOVVconst [int64(uint64(c)%uint64(d))]) // mod
609(ANDconst [c] (MOVVconst [d])) => (MOVVconst [c&d])
610(ANDconst [c] (ANDconst [d] x)) => (ANDconst [c&d] x)
611(ORconst [c] (MOVVconst [d])) => (MOVVconst [c|d])
612(ORconst [c] (ORconst [d] x)) && is32Bit(c|d) => (ORconst [c|d] x)
613(XORconst [c] (MOVVconst [d])) => (MOVVconst [c^d])
614(XORconst [c] (XORconst [d] x)) && is32Bit(c^d) => (XORconst [c^d] x)
615(NORconst [c] (MOVVconst [d])) => (MOVVconst [^(c|d)])
616(NEGV (MOVVconst [c])) => (MOVVconst [-c])
617(MOVBreg  (MOVVconst [c])) => (MOVVconst [int64(int8(c))])
618(MOVBUreg (MOVVconst [c])) => (MOVVconst [int64(uint8(c))])
619(MOVHreg  (MOVVconst [c])) => (MOVVconst [int64(int16(c))])
620(MOVHUreg (MOVVconst [c])) => (MOVVconst [int64(uint16(c))])
621(MOVWreg  (MOVVconst [c])) => (MOVVconst [int64(int32(c))])
622(MOVWUreg (MOVVconst [c])) => (MOVVconst [int64(uint32(c))])
623(MOVVreg  (MOVVconst [c])) => (MOVVconst [c])
624
625// constant comparisons
626(SGTconst [c] (MOVVconst [d])) && c>d => (MOVVconst [1])
627(SGTconst [c] (MOVVconst [d])) && c<=d => (MOVVconst [0])
628(SGTUconst [c] (MOVVconst [d])) && uint64(c)>uint64(d) => (MOVVconst [1])
629(SGTUconst [c] (MOVVconst [d])) && uint64(c)<=uint64(d) => (MOVVconst [0])
630
631// other known comparisons
632(SGTconst [c] (MOVBreg _)) && 0x7f < c => (MOVVconst [1])
633(SGTconst [c] (MOVBreg _)) && c <= -0x80 => (MOVVconst [0])
634(SGTconst [c] (MOVBUreg _)) && 0xff < c => (MOVVconst [1])
635(SGTconst [c] (MOVBUreg _)) && c < 0 => (MOVVconst [0])
636(SGTUconst [c] (MOVBUreg _)) && 0xff < uint64(c) => (MOVVconst [1])
637(SGTconst [c] (MOVHreg _)) && 0x7fff < c => (MOVVconst [1])
638(SGTconst [c] (MOVHreg _)) && c <= -0x8000 => (MOVVconst [0])
639(SGTconst [c] (MOVHUreg _)) && 0xffff < c => (MOVVconst [1])
640(SGTconst [c] (MOVHUreg _)) && c < 0 => (MOVVconst [0])
641(SGTUconst [c] (MOVHUreg _)) && 0xffff < uint64(c) => (MOVVconst [1])
642(SGTconst [c] (MOVWUreg _)) && c < 0 => (MOVVconst [0])
643(SGTconst [c] (ANDconst [m] _)) && 0 <= m && m < c => (MOVVconst [1])
644(SGTUconst [c] (ANDconst [m] _)) && uint64(m) < uint64(c) => (MOVVconst [1])
645(SGTconst [c] (SRLVconst _ [d])) && 0 <= c && 0 < d && d <= 63 && 0xffffffffffffffff>>uint64(d) < uint64(c) => (MOVVconst [1])
646(SGTUconst [c] (SRLVconst _ [d])) && 0 < d && d <= 63 && 0xffffffffffffffff>>uint64(d) < uint64(c) => (MOVVconst [1])
647
648// absorb constants into branches
649(EQ  (MOVVconst [0]) yes no) => (First yes no)
650(EQ  (MOVVconst [c]) yes no) && c != 0 => (First no yes)
651(NE  (MOVVconst [0]) yes no) => (First no yes)
652(NE  (MOVVconst [c]) yes no) && c != 0 => (First yes no)
653(LTZ (MOVVconst [c]) yes no) && c <  0 => (First yes no)
654(LTZ (MOVVconst [c]) yes no) && c >= 0 => (First no yes)
655(LEZ (MOVVconst [c]) yes no) && c <= 0 => (First yes no)
656(LEZ (MOVVconst [c]) yes no) && c >  0 => (First no yes)
657(GTZ (MOVVconst [c]) yes no) && c >  0 => (First yes no)
658(GTZ (MOVVconst [c]) yes no) && c <= 0 => (First no yes)
659(GEZ (MOVVconst [c]) yes no) && c >= 0 => (First yes no)
660(GEZ (MOVVconst [c]) yes no) && c <  0 => (First no yes)
661
662// SGT/SGTU with known outcomes.
663(SGT  x x) => (MOVVconst [0])
664(SGTU x x) => (MOVVconst [0])
665