-- .mod --
module example.com/retract

go 1.15

-- .info --
{"Version":"v1.0.0-good"}

-- retract.go --

// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Fold constant shift with extension.
(SRAI [c] (MOVBreg  x)) && c <   8 => (SRAI [56+c] (SLLI <typ.Int64> [56] x))
(SRAI [c] (MOVHreg  x)) && c <  16 => (SRAI [48+c] (SLLI <typ.Int64> [48] x))
(SRAI [c] (MOVWreg  x)) && c <  32 => (SRAI [32+c] (SLLI <typ.Int64> [32] x))

(LT (CMPWconst [0] x) yes no) => (TBNZ [31] x yes no)
(LT (CMPconst [0] x)  yes no) => (TBNZ [63] x yes no)

// fold offset into address
(ADDconst [off1] (MOVDaddr [off2] {sym} ptr)) && is32Bit(off1+int64(off2)) =>
	 (MOVDaddr [int32(off1)+off2] {sym} ptr)

// fold address into load/store.
// Do not fold global variable access in -dynlink mode, where it will
// be rewritten to use the GOT via REGTMP, which currently cannot handle

m
m/dir
m/dir2
m/dir3
-- go.mod --
// TODO(#39958): Support and test overlays including go.mod itself (especially if mod=readonly)
module m

go 1.16

-- dir2/h.go --
package dir2

-- dir3/good.go --
package dir3
-- dir3/bad.go --
// no package statement
-- overlay.json --
{
    "Replace": {
        "f.go": "overlay/f_go",
        "dir/g.go": "overlay/dir_g_go",

(EQ (SGT x (MOVVconst [0])) yes no) => (LEZ x yes no)
(MOVBUreg x:((SGT|SGTU) _ _)) => x

// fold offset into address
(ADDVconst [off1] (MOVVaddr [off2] {sym} ptr)) && is32Bit(off1+int64(off2)) => (MOVVaddr [int32(off1)+int32(off2)] {sym} ptr)

// fold address into load/store
// Do not fold global variable access in -dynlink mode, where it will be rewritten

(EQ (SGTconst [0] x) yes no) => (GEZ x yes no)
(NE (SGTzero x) yes no) => (GTZ x yes no)
(EQ (SGTzero x) yes no) => (LEZ x yes no)

// fold offset into address
(ADDconst [off1] (MOVWaddr [off2] {sym} ptr)) => (MOVWaddr [off1+off2] {sym} ptr)

// fold address into load/store
(MOVBload  [off1] {sym} x:(ADDconst [off2] ptr) mem) && (is16Bit(int64(off1+off2)) || x.Uses == 1) => (MOVBload  [off1+off2] {sym} ptr mem)

(NE (SGT x (MOVVconst [0])) yes no) => (GTZ x yes no)
(EQ (SGT x (MOVVconst [0])) yes no) => (LEZ x yes no)

// fold offset into address
(ADDVconst [off1] (MOVVaddr [off2] {sym} ptr)) && is32Bit(off1+int64(off2)) => (MOVVaddr [int32(off1)+int32(off2)] {sym} ptr)

// fold address into load/store
(MOVBload  [off1] {sym} (ADDVconst [off2] ptr) mem) && is32Bit(int64(off1)+off2)

(MOVWreg x:(Arg <t>)) && t.IsSigned() && t.Size() <= 4 => x

// Fold zero extensions into constants.
(MOVBZreg (MOVDconst [c])) => (MOVDconst [int64( uint8(c))])
(MOVHZreg (MOVDconst [c])) => (MOVDconst [int64(uint16(c))])
(MOVWZreg (MOVDconst [c])) => (MOVDconst [int64(uint32(c))])

// Fold sign extensions into constants.
(MOVBreg (MOVDconst [c])) => (MOVDconst [int64( int8(c))])

(MOVWreg  x:(MOVHUloadidx2 _ _ _)) => (MOVDreg x)
(MOVWreg  x:(MOVWloadidx4  _ _ _)) => (MOVDreg x)
(MOVWUreg x:(MOVHUloadidx2 _ _ _)) => (MOVDreg x)
(MOVWUreg x:(MOVWUloadidx4 _ _ _)) => (MOVDreg x)

// fold double extensions
(MOVBreg  x:(MOVBreg  _)) => (MOVDreg x)
(MOVBUreg x:(MOVBUreg _)) => (MOVDreg x)
(MOVHreg  x:(MOVBreg  _)) => (MOVDreg x)
(MOVHreg  x:(MOVBUreg _)) => (MOVDreg x)
(MOVHreg  x:(MOVHreg  _)) => (MOVDreg x)

    => (SET(B|AE)store [off] {sym} ptr (BTLconst [31] x) mem)

// Fold combinations of bit ops on same bit. An example is math.Copysign(c,-1)
(BTSQconst [c] (BTRQconst [c] x)) => (BTSQconst [c] x)
(BTSQconst [c] (BTCQconst [c] x)) => (BTSQconst [c] x)
(BTRQconst [c] (BTSQconst [c] x)) => (BTRQconst [c] x)
(BTRQconst [c] (BTCQconst [c] x)) => (BTRQconst [c] x)

// Fold boolean negation into SETcc.
(XORLconst [1] (SETNE x)) => (SETEQ x)