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1// Copyright 2018 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// Lowering arithmetic
6(Add(64|32|16|8|Ptr) ...) => (I64Add ...)
7(Add(64|32)F ...) => (F(64|32)Add ...)
8
9(Sub(64|32|16|8|Ptr) ...) => (I64Sub ...)
10(Sub(64|32)F ...) => (F(64|32)Sub ...)
11
12(Mul(64|32|16|8) ...) => (I64Mul ...)
13(Mul(64|32)F ...) => (F(64|32)Mul ...)
14
15(Div64 [false] x y) => (I64DivS x y)
16(Div32 [false] x y) => (I64DivS (SignExt32to64 x) (SignExt32to64 y))
17(Div16 [false] x y) => (I64DivS (SignExt16to64 x) (SignExt16to64 y))
18(Div8          x y) => (I64DivS (SignExt8to64 x) (SignExt8to64 y))
19(Div64u ...) => (I64DivU ...)
20(Div32u x y) => (I64DivU (ZeroExt32to64 x) (ZeroExt32to64 y))
21(Div16u x y) => (I64DivU (ZeroExt16to64 x) (ZeroExt16to64 y))
22(Div8u  x y) => (I64DivU (ZeroExt8to64 x) (ZeroExt8to64 y))
23(Div(64|32)F ...) => (F(64|32)Div ...)
24
25(Mod64 [false] x y) => (I64RemS x y)
26(Mod32 [false] x y) => (I64RemS (SignExt32to64 x) (SignExt32to64 y))
27(Mod16 [false] x y) => (I64RemS (SignExt16to64 x) (SignExt16to64 y))
28(Mod8          x y) => (I64RemS (SignExt8to64  x) (SignExt8to64  y))
29(Mod64u ...) => (I64RemU ...)
30(Mod32u x y) => (I64RemU (ZeroExt32to64 x) (ZeroExt32to64 y))
31(Mod16u x y) => (I64RemU (ZeroExt16to64 x) (ZeroExt16to64 y))
32(Mod8u  x y) => (I64RemU (ZeroExt8to64  x) (ZeroExt8to64  y))
33
34(And(64|32|16|8|B) ...) => (I64And ...)
35
36(Or(64|32|16|8|B) ...) => (I64Or ...)
37
38(Xor(64|32|16|8) ...) => (I64Xor ...)
39
40(Neg(64|32|16|8) x) => (I64Sub (I64Const [0]) x)
41(Neg(64|32)F ...) => (F(64|32)Neg ...)
42
43(Com(64|32|16|8) x) => (I64Xor x (I64Const [-1]))
44
45(Not ...) => (I64Eqz ...)
46
47// Lowering pointer arithmetic
48(OffPtr ...) => (I64AddConst ...)
49
50// Lowering extension
51// It is unnecessary to extend loads
52(SignExt32to64        x:(I64Load32S _ _)) => x
53(SignExt16to(64|32)   x:(I64Load16S _ _)) => x
54(SignExt8to(64|32|16) x:(I64Load8S  _ _)) => x
55(ZeroExt32to64        x:(I64Load32U _ _)) => x
56(ZeroExt16to(64|32)   x:(I64Load16U _ _)) => x
57(ZeroExt8to(64|32|16) x:(I64Load8U  _ _)) => x
58(SignExt32to64        x) && buildcfg.GOWASM.SignExt => (I64Extend32S x)
59(SignExt8to(64|32|16) x) && buildcfg.GOWASM.SignExt => (I64Extend8S x)
60(SignExt16to(64|32)   x) && buildcfg.GOWASM.SignExt => (I64Extend16S x)
61(SignExt32to64        x) => (I64ShrS (I64Shl x (I64Const [32])) (I64Const [32]))
62(SignExt16to(64|32)   x) => (I64ShrS (I64Shl x (I64Const [48])) (I64Const [48]))
63(SignExt8to(64|32|16) x) => (I64ShrS (I64Shl x (I64Const [56])) (I64Const [56]))
64(ZeroExt32to64        x) => (I64And x (I64Const [0xffffffff]))
65(ZeroExt16to(64|32)   x) => (I64And x (I64Const [0xffff]))
66(ZeroExt8to(64|32|16) x) => (I64And x (I64Const [0xff]))
67
68(Slicemask x) => (I64ShrS (I64Sub (I64Const [0]) x) (I64Const [63]))
69
70// Lowering truncation
71// Because we ignore the high parts, truncates are just copies.
72(Trunc64to(32|16|8) ...) => (Copy ...)
73(Trunc32to(16|8)    ...) => (Copy ...)
74(Trunc16to8         ...) => (Copy ...)
75
76// Lowering float <=> int
77(Cvt32to(64|32)F x) => (F(64|32)ConvertI64S (SignExt32to64 x))
78(Cvt64to(64|32)F ...) => (F(64|32)ConvertI64S ...)
79(Cvt32Uto(64|32)F x) => (F(64|32)ConvertI64U (ZeroExt32to64 x))
80(Cvt64Uto(64|32)F ...) => (F(64|32)ConvertI64U ...)
81
82(Cvt32Fto32 ...) => (I64TruncSatF32S ...)
83(Cvt32Fto64 ...) => (I64TruncSatF32S ...)
84(Cvt64Fto32 ...) => (I64TruncSatF64S ...)
85(Cvt64Fto64 ...) => (I64TruncSatF64S ...)
86(Cvt32Fto32U ...) => (I64TruncSatF32U ...)
87(Cvt32Fto64U ...) => (I64TruncSatF32U ...)
88(Cvt64Fto32U ...) => (I64TruncSatF64U ...)
89(Cvt64Fto64U ...) => (I64TruncSatF64U ...)
90
91(Cvt32Fto64F ...) => (F64PromoteF32 ...)
92(Cvt64Fto32F ...) => (F32DemoteF64 ...)
93
94(CvtBoolToUint8 ...) => (Copy ...)
95
96(Round32F ...) => (Copy ...)
97(Round64F ...) => (Copy ...)
98
99// Lowering shifts
100// Unsigned shifts need to return 0 if shift amount is >= width of shifted value.
101
102(Lsh64x64 x y) && shiftIsBounded(v) => (I64Shl x y)
103(Lsh64x64 x (I64Const [c])) && uint64(c) < 64 => (I64Shl x (I64Const [c]))
104(Lsh64x64 x (I64Const [c])) && uint64(c) >= 64 => (I64Const [0])
105(Lsh64x64 x y) => (Select (I64Shl x y) (I64Const [0]) (I64LtU y (I64Const [64])))
106(Lsh64x(32|16|8) [c] x y) => (Lsh64x64 [c] x (ZeroExt(32|16|8)to64 y))
107
108(Lsh32x64 ...) => (Lsh64x64 ...)
109(Lsh32x(32|16|8) [c] x y) => (Lsh64x64 [c] x (ZeroExt(32|16|8)to64 y))
110
111(Lsh16x64 ...) => (Lsh64x64 ...)
112(Lsh16x(32|16|8) [c] x y) => (Lsh64x64 [c] x (ZeroExt(32|16|8)to64 y))
113
114(Lsh8x64 ...) => (Lsh64x64 ...)
115(Lsh8x(32|16|8) [c] x y) => (Lsh64x64 [c] x (ZeroExt(32|16|8)to64 y))
116
117(Rsh64Ux64 x y) && shiftIsBounded(v) => (I64ShrU x y)
118(Rsh64Ux64 x (I64Const [c])) && uint64(c) < 64 => (I64ShrU x (I64Const [c]))
119(Rsh64Ux64 x (I64Const [c])) && uint64(c) >= 64 => (I64Const [0])
120(Rsh64Ux64 x y) => (Select (I64ShrU x y) (I64Const [0]) (I64LtU y (I64Const [64])))
121(Rsh64Ux(32|16|8) [c] x y) => (Rsh64Ux64 [c] x (ZeroExt(32|16|8)to64 y))
122
123(Rsh32Ux64 [c] x y) => (Rsh64Ux64 [c] (ZeroExt32to64 x) y)
124(Rsh32Ux(32|16|8) [c] x y) => (Rsh64Ux64 [c] (ZeroExt32to64 x) (ZeroExt(32|16|8)to64 y))
125
126(Rsh16Ux64 [c] x y) => (Rsh64Ux64 [c] (ZeroExt16to64 x) y)
127(Rsh16Ux(32|16|8) [c] x y) => (Rsh64Ux64 [c] (ZeroExt16to64 x) (ZeroExt(32|16|8)to64 y))
128
129(Rsh8Ux64 [c] x y) => (Rsh64Ux64 [c] (ZeroExt8to64 x) y)
130(Rsh8Ux(32|16|8) [c] x y) => (Rsh64Ux64 [c] (ZeroExt8to64 x) (ZeroExt(32|16|8)to64 y))
131
132// Signed right shift needs to return 0/-1 if shift amount is >= width of shifted value.
133// We implement this by setting the shift value to (width - 1) if the shift value is >= width.
134
135(Rsh64x64 x y) && shiftIsBounded(v) => (I64ShrS x y)
136(Rsh64x64 x (I64Const [c])) && uint64(c) < 64 => (I64ShrS x (I64Const [c]))
137(Rsh64x64 x (I64Const [c])) && uint64(c) >= 64 => (I64ShrS x (I64Const [63]))
138(Rsh64x64 x y) => (I64ShrS x (Select <typ.Int64> y (I64Const [63]) (I64LtU y (I64Const [64]))))
139(Rsh64x(32|16|8) [c] x y) => (Rsh64x64 [c] x (ZeroExt(32|16|8)to64 y))
140
141(Rsh32x64 [c] x y) => (Rsh64x64 [c] (SignExt32to64 x) y)
142(Rsh32x(32|16|8) [c] x y) => (Rsh64x64 [c] (SignExt32to64 x) (ZeroExt(32|16|8)to64 y))
143
144(Rsh16x64 [c] x y) => (Rsh64x64 [c] (SignExt16to64 x) y)
145(Rsh16x(32|16|8) [c] x y) => (Rsh64x64 [c] (SignExt16to64 x) (ZeroExt(32|16|8)to64 y))
146
147(Rsh8x64 [c] x y)  => (Rsh64x64 [c] (SignExt8to64 x) y)
148(Rsh8x(32|16|8) [c] x y)  => (Rsh64x64 [c] (SignExt8to64 x) (ZeroExt(32|16|8)to64 y))
149
150// Lowering rotates
151(RotateLeft8 <t> x (I64Const [c])) => (Or8 (Lsh8x64 <t> x (I64Const [c&7])) (Rsh8Ux64 <t> x (I64Const [-c&7])))
152(RotateLeft16 <t> x (I64Const [c])) => (Or16 (Lsh16x64 <t> x (I64Const [c&15])) (Rsh16Ux64 <t> x (I64Const [-c&15])))
153(RotateLeft32 ...) => (I32Rotl ...)
154(RotateLeft64 ...) => (I64Rotl ...)
155
156// Lowering comparisons
157(Less64  ...) => (I64LtS ...)
158(Less32  x y) => (I64LtS (SignExt32to64 x) (SignExt32to64 y))
159(Less16  x y) => (I64LtS (SignExt16to64 x) (SignExt16to64 y))
160(Less8   x y) => (I64LtS (SignExt8to64  x) (SignExt8to64  y))
161(Less64U ...) => (I64LtU ...)
162(Less32U x y) => (I64LtU (ZeroExt32to64 x) (ZeroExt32to64 y))
163(Less16U x y) => (I64LtU (ZeroExt16to64 x) (ZeroExt16to64 y))
164(Less8U  x y) => (I64LtU (ZeroExt8to64  x) (ZeroExt8to64  y))
165(Less(64|32)F ...) => (F(64|32)Lt ...)
166
167(Leq64  ...) => (I64LeS ...)
168(Leq32  x y) => (I64LeS (SignExt32to64 x) (SignExt32to64 y))
169(Leq16  x y) => (I64LeS (SignExt16to64 x) (SignExt16to64 y))
170(Leq8   x y) => (I64LeS (SignExt8to64  x) (SignExt8to64  y))
171(Leq64U ...) => (I64LeU ...)
172(Leq32U x y) => (I64LeU (ZeroExt32to64 x) (ZeroExt32to64 y))
173(Leq16U x y) => (I64LeU (ZeroExt16to64 x) (ZeroExt16to64 y))
174(Leq8U  x y) => (I64LeU (ZeroExt8to64  x) (ZeroExt8to64  y))
175(Leq(64|32)F ...) => (F(64|32)Le ...)
176
177(Eq64  ...) => (I64Eq ...)
178(Eq32  x y) => (I64Eq (ZeroExt32to64 x) (ZeroExt32to64 y))
179(Eq16  x y) => (I64Eq (ZeroExt16to64 x) (ZeroExt16to64 y))
180(Eq8   x y) => (I64Eq (ZeroExt8to64  x) (ZeroExt8to64  y))
181(EqB   ...) => (I64Eq ...)
182(EqPtr ...) => (I64Eq ...)
183(Eq(64|32)F ...) => (F(64|32)Eq ...)
184
185(Neq64  ...) => (I64Ne ...)
186(Neq32  x y) => (I64Ne (ZeroExt32to64 x) (ZeroExt32to64 y))
187(Neq16  x y) => (I64Ne (ZeroExt16to64 x) (ZeroExt16to64 y))
188(Neq8   x y) => (I64Ne (ZeroExt8to64  x) (ZeroExt8to64  y))
189(NeqB   ...) => (I64Ne ...)
190(NeqPtr ...) => (I64Ne ...)
191(Neq(64|32)F ...) => (F(64|32)Ne ...)
192
193// Lowering loads
194(Load <t> ptr mem) && is32BitFloat(t) => (F32Load ptr mem)
195(Load <t> ptr mem) && is64BitFloat(t) => (F64Load ptr mem)
196(Load <t> ptr mem) && t.Size() == 8 => (I64Load ptr mem)
197(Load <t> ptr mem) && t.Size() == 4 && !t.IsSigned() => (I64Load32U ptr mem)
198(Load <t> ptr mem) && t.Size() == 4 &&  t.IsSigned() => (I64Load32S ptr mem)
199(Load <t> ptr mem) && t.Size() == 2 && !t.IsSigned() => (I64Load16U ptr mem)
200(Load <t> ptr mem) && t.Size() == 2 &&  t.IsSigned() => (I64Load16S ptr mem)
201(Load <t> ptr mem) && t.Size() == 1 && !t.IsSigned() => (I64Load8U ptr mem)
202(Load <t> ptr mem) && t.Size() == 1 &&  t.IsSigned() => (I64Load8S ptr mem)
203
204// Lowering stores
205(Store {t} ptr val mem) && is64BitFloat(t) => (F64Store ptr val mem)
206(Store {t} ptr val mem) && is32BitFloat(t) => (F32Store ptr val mem)
207(Store {t} ptr val mem) && t.Size() == 8 => (I64Store ptr val mem)
208(Store {t} ptr val mem) && t.Size() == 4 => (I64Store32 ptr val mem)
209(Store {t} ptr val mem) && t.Size() == 2 => (I64Store16 ptr val mem)
210(Store {t} ptr val mem) && t.Size() == 1 => (I64Store8 ptr val mem)
211
212// Lowering moves
213(Move [0] _ _ mem) => mem
214(Move [1] dst src mem) => (I64Store8 dst (I64Load8U src mem) mem)
215(Move [2] dst src mem) => (I64Store16 dst (I64Load16U src mem) mem)
216(Move [4] dst src mem) => (I64Store32 dst (I64Load32U src mem) mem)
217(Move [8] dst src mem) => (I64Store dst (I64Load src mem) mem)
218(Move [16] dst src mem) =>
219	(I64Store [8] dst (I64Load [8] src mem)
220		(I64Store dst (I64Load src mem) mem))
221(Move [3] dst src mem) =>
222	(I64Store8 [2] dst (I64Load8U [2] src mem)
223		(I64Store16 dst (I64Load16U src mem) mem))
224(Move [5] dst src mem) =>
225	(I64Store8 [4] dst (I64Load8U [4] src mem)
226		(I64Store32 dst (I64Load32U src mem) mem))
227(Move [6] dst src mem) =>
228	(I64Store16 [4] dst (I64Load16U [4] src mem)
229		(I64Store32 dst (I64Load32U src mem) mem))
230(Move [7] dst src mem) =>
231	(I64Store32 [3] dst (I64Load32U [3] src mem)
232		(I64Store32 dst (I64Load32U src mem) mem))
233(Move [s] dst src mem) && s > 8 && s < 16 =>
234	(I64Store [s-8] dst (I64Load [s-8] src mem)
235		(I64Store dst (I64Load src mem) mem))
236
237// Large copying uses helper.
238(Move [s] dst src mem) && logLargeCopy(v, s) =>
239	(LoweredMove [s] dst src mem)
240
241// Lowering Zero instructions
242(Zero [0] _ mem) => mem
243(Zero [1] destptr mem) => (I64Store8 destptr (I64Const [0]) mem)
244(Zero [2] destptr mem) => (I64Store16 destptr (I64Const [0]) mem)
245(Zero [4] destptr mem) => (I64Store32 destptr (I64Const [0]) mem)
246(Zero [8] destptr mem) => (I64Store destptr (I64Const [0]) mem)
247
248(Zero [3] destptr mem) =>
249	(I64Store8 [2] destptr (I64Const [0])
250		(I64Store16 destptr (I64Const [0]) mem))
251(Zero [5] destptr mem) =>
252	(I64Store8 [4] destptr (I64Const [0])
253		(I64Store32 destptr (I64Const [0]) mem))
254(Zero [6] destptr mem) =>
255	(I64Store16 [4] destptr (I64Const [0])
256		(I64Store32 destptr (I64Const [0]) mem))
257(Zero [7] destptr mem) =>
258	(I64Store32 [3] destptr (I64Const [0])
259		(I64Store32 destptr (I64Const [0]) mem))
260
261// Strip off any fractional word zeroing.
262(Zero [s] destptr mem) && s%8 != 0 && s > 8 && s < 32 =>
263	(Zero [s-s%8] (OffPtr <destptr.Type> destptr [s%8])
264		(I64Store destptr (I64Const [0]) mem))
265
266// Zero small numbers of words directly.
267(Zero [16] destptr mem) =>
268	(I64Store [8] destptr (I64Const [0])
269		(I64Store destptr (I64Const [0]) mem))
270(Zero [24] destptr mem) =>
271	(I64Store [16] destptr (I64Const [0])
272		(I64Store [8] destptr (I64Const [0])
273			(I64Store destptr (I64Const [0]) mem)))
274(Zero [32] destptr mem) =>
275	(I64Store [24] destptr (I64Const [0])
276		(I64Store [16] destptr (I64Const [0])
277			(I64Store [8] destptr (I64Const [0])
278				(I64Store destptr (I64Const [0]) mem))))
279
280// Large zeroing uses helper.
281(Zero [s] destptr mem) =>
282	(LoweredZero [s] destptr mem)
283
284// Lowering constants
285(Const64 ...) => (I64Const ...)
286(Const(32|16|8) [c]) => (I64Const [int64(c)])
287(Const(64|32)F ...) => (F(64|32)Const ...)
288(ConstNil) => (I64Const [0])
289(ConstBool [c]) => (I64Const [b2i(c)])
290
291// Lowering calls
292(StaticCall ...) => (LoweredStaticCall ...)
293(ClosureCall ...) => (LoweredClosureCall ...)
294(InterCall ...) => (LoweredInterCall ...)
295(TailCall ...) => (LoweredTailCall ...)
296
297// Miscellaneous
298(Convert ...) => (LoweredConvert ...)
299(IsNonNil p) => (I64Eqz (I64Eqz p))
300(IsInBounds ...) => (I64LtU ...)
301(IsSliceInBounds ...) => (I64LeU ...)
302(NilCheck ...) => (LoweredNilCheck ...)
303(GetClosurePtr ...) => (LoweredGetClosurePtr ...)
304(GetCallerPC ...) => (LoweredGetCallerPC ...)
305(GetCallerSP ...) => (LoweredGetCallerSP ...)
306(Addr {sym} base) => (LoweredAddr {sym} [0] base)
307(LocalAddr <t> {sym} base mem) && t.Elem().HasPointers() => (LoweredAddr {sym} (SPanchored base mem))
308(LocalAddr <t> {sym} base _)  && !t.Elem().HasPointers() => (LoweredAddr {sym} base)
309
310// Write barrier.
311(WB ...) => (LoweredWB ...)
312
313// --- Intrinsics ---
314(Sqrt ...) => (F64Sqrt ...)
315(Trunc ...) => (F64Trunc ...)
316(Ceil ...) => (F64Ceil ...)
317(Floor ...) => (F64Floor ...)
318(RoundToEven ...) => (F64Nearest ...)
319(Abs ...) => (F64Abs ...)
320(Copysign ...) => (F64Copysign ...)
321
322(Sqrt32 ...) => (F32Sqrt ...)
323
324(Ctz64 ...) => (I64Ctz ...)
325(Ctz32 x) => (I64Ctz (I64Or x (I64Const [0x100000000])))
326(Ctz16 x) => (I64Ctz (I64Or x (I64Const [0x10000])))
327(Ctz8  x) => (I64Ctz (I64Or x (I64Const [0x100])))
328
329(Ctz(64|32|16|8)NonZero ...) => (I64Ctz ...)
330
331(BitLen64 x) => (I64Sub (I64Const [64]) (I64Clz x))
332
333(PopCount64 ...) => (I64Popcnt ...)
334(PopCount32 x) => (I64Popcnt (ZeroExt32to64 x))
335(PopCount16 x) => (I64Popcnt (ZeroExt16to64 x))
336(PopCount8  x) => (I64Popcnt (ZeroExt8to64  x))
337
338(CondSelect ...) => (Select ...)
339
340// --- Optimizations ---
341(I64Add (I64Const [x]) (I64Const [y])) => (I64Const [x + y])
342(I64Mul (I64Const [x]) (I64Const [y])) => (I64Const [x * y])
343(I64And (I64Const [x]) (I64Const [y])) => (I64Const [x & y])
344(I64Or  (I64Const [x]) (I64Const [y])) => (I64Const [x | y])
345(I64Xor (I64Const [x]) (I64Const [y])) => (I64Const [x ^ y])
346(F64Add (F64Const [x]) (F64Const [y])) => (F64Const [x + y])
347(F64Mul (F64Const [x]) (F64Const [y])) && !math.IsNaN(x * y) => (F64Const [x * y])
348(I64Eq  (I64Const [x]) (I64Const [y])) && x == y => (I64Const [1])
349(I64Eq  (I64Const [x]) (I64Const [y])) && x != y => (I64Const [0])
350(I64Ne  (I64Const [x]) (I64Const [y])) && x == y => (I64Const [0])
351(I64Ne  (I64Const [x]) (I64Const [y])) && x != y => (I64Const [1])
352
353(I64Shl (I64Const [x]) (I64Const [y])) => (I64Const [x << uint64(y)])
354(I64ShrU (I64Const [x]) (I64Const [y])) => (I64Const [int64(uint64(x) >> uint64(y))])
355(I64ShrS (I64Const [x]) (I64Const [y])) => (I64Const [x >> uint64(y)])
356
357// TODO: declare these operations as commutative and get rid of these rules?
358(I64Add (I64Const [x]) y) && y.Op != OpWasmI64Const => (I64Add y (I64Const [x]))
359(I64Mul (I64Const [x]) y) && y.Op != OpWasmI64Const => (I64Mul y (I64Const [x]))
360(I64And (I64Const [x]) y) && y.Op != OpWasmI64Const => (I64And y (I64Const [x]))
361(I64Or  (I64Const [x]) y) && y.Op != OpWasmI64Const => (I64Or  y (I64Const [x]))
362(I64Xor (I64Const [x]) y) && y.Op != OpWasmI64Const => (I64Xor y (I64Const [x]))
363(F64Add (F64Const [x]) y) && y.Op != OpWasmF64Const => (F64Add y (F64Const [x]))
364(F64Mul (F64Const [x]) y) && y.Op != OpWasmF64Const => (F64Mul y (F64Const [x]))
365(I64Eq  (I64Const [x]) y) && y.Op != OpWasmI64Const => (I64Eq y  (I64Const [x]))
366(I64Ne  (I64Const [x]) y) && y.Op != OpWasmI64Const => (I64Ne y  (I64Const [x]))
367
368(I64Eq x (I64Const [0])) => (I64Eqz x)
369(I64LtU (I64Const [0]) x) => (I64Eqz (I64Eqz x))
370(I64LeU x (I64Const [0])) => (I64Eqz x)
371(I64LtU x (I64Const [1])) => (I64Eqz x)
372(I64LeU (I64Const [1]) x) => (I64Eqz (I64Eqz x))
373(I64Ne x (I64Const [0])) => (I64Eqz (I64Eqz x))
374
375(I64Add x (I64Const <t> [y])) && !t.IsPtr() => (I64AddConst [y] x)
376(I64AddConst [0] x) => x
377(I64Eqz (I64Eqz (I64Eqz x))) => (I64Eqz x)
378
379// folding offset into load/store
380((I64Load|I64Load32U|I64Load32S|I64Load16U|I64Load16S|I64Load8U|I64Load8S) [off] (I64AddConst [off2] ptr) mem)
381	&& isU32Bit(off+off2) =>
382	((I64Load|I64Load32U|I64Load32S|I64Load16U|I64Load16S|I64Load8U|I64Load8S) [off+off2] ptr mem)
383
384((I64Store|I64Store32|I64Store16|I64Store8) [off] (I64AddConst [off2] ptr) val mem)
385	&& isU32Bit(off+off2) =>
386	((I64Store|I64Store32|I64Store16|I64Store8) [off+off2] ptr val mem)
387
388// folding offset into address
389(I64AddConst [off] (LoweredAddr {sym} [off2] base)) && isU32Bit(off+int64(off2)) =>
390	(LoweredAddr {sym} [int32(off)+off2] base)
391(I64AddConst [off] x:(SP)) && isU32Bit(off) => (LoweredAddr [int32(off)] x) // so it is rematerializeable
392
393// transforming readonly globals into constants
394(I64Load [off] (LoweredAddr {sym} [off2] (SB)) _) && symIsRO(sym) && isU32Bit(off+int64(off2)) => (I64Const [int64(read64(sym, off+int64(off2), config.ctxt.Arch.ByteOrder))])
395(I64Load32U [off] (LoweredAddr {sym} [off2] (SB)) _) && symIsRO(sym) && isU32Bit(off+int64(off2)) => (I64Const [int64(read32(sym, off+int64(off2), config.ctxt.Arch.ByteOrder))])
396(I64Load16U [off] (LoweredAddr {sym} [off2] (SB)) _) && symIsRO(sym) && isU32Bit(off+int64(off2)) => (I64Const [int64(read16(sym, off+int64(off2), config.ctxt.Arch.ByteOrder))])
397(I64Load8U [off] (LoweredAddr {sym} [off2] (SB)) _) && symIsRO(sym) && isU32Bit(off+int64(off2)) => (I64Const [int64(read8(sym, off+int64(off2)))])
398