(MSUB a (MOVDconst [-1]) x) => (ADD a x)
(MSUB a (MOVDconst [0]) _) => a
(MSUB a (MOVDconst [1]) x) => (SUB a x)
(MSUB a (MOVDconst [c]) x) && isPowerOfTwo64(c) => (SUBshiftLL a x [log64(c)])
(MSUB a (MOVDconst [c]) x) && isPowerOfTwo64(c-1) && c>=3 => (SUB a (ADDshiftLL <x.Type> x x [log64(c-1)]))
(MSUB a (MOVDconst [c]) x) && isPowerOfTwo64(c+1) && c>=7 => (ADD a (SUBshiftLL <x.Type> x x [log64(c+1)]))

func main() {
	easysub.Hello()
}
-- testdata/local/hard.go --
package main

import "./sub"

func main() {
	sub.Hello()
}
-- testdata/local/sub/sub.go --
package sub

import (
	"fmt"

	subsub "./sub"
)

func Hello() {
	fmt.Println("sub.Hello")
	subsub.Hello()
}
-- testdata/local/sub/sub/subsub.go --
package subsub

import "fmt"

func Hello() {

# with '-buildvcs=auto'.

go build -o sub.exe ./sub
go version -m sub.exe
! stdout '^\tbuild\tvcs'

! go build -buildvcs -o sub.exe ./sub
stderr '\Aerror obtaining VCS status: main package is in repository ".*" but current directory is in repository ".*"\n\tUse -buildvcs=false to disable VCS stamping.\n\z'

cd ./sub
go build -o sub.exe .
go version -m sub.exe
! stdout '^\tbuild\tvcs'

go 1.19

require (
	b v0.1.0
	c v0.2.0
)
-- a2/a.go --
package a

import (
	_ "b"
	_ "c"
)
-- a2/sub/sub.go --
package sub
-- a3/go.mod --
module a

go 1.19

require b v0.2.0
-- a3/a.go --
package a

import _ "b"
-- a3/sub/sub.go --
package sub
-- b1/go.mod --
module b

go 1.19
-- b1/b.go --
package b
-- b2/go.mod --
module b

go 1.19

module mod.example

go 1.20

require rsc.io/quote/v3 v3.0.0

-- main/main.go --
package main

import (
	"fmt"
	"mod.example/sub"

	"rsc.io/quote"
)

func main() {
	fmt.Println(quote.Go(), sub.F())
}

-- sub/sub.go --

package sub

func F() int {
	return 42

git add another.txt
git commit -a -m 'another'
git tag v2.0.2

at 2018-04-17T16:16:52-04:00
git checkout master
git branch v3
git checkout v3
mkdir v3/sub/dir
echo 'v3/sub/dir/file'
cp stdout v3/sub/dir/file.txt
git add v3
git commit -a -m 'add v3/sub/dir/file.txt'

at 2018-04-17T22:23:00-04:00
git checkout master
git tag -a v1.2.4-annotated -m 'v1.2.4-annotated'

git show-ref --tags --heads

  comparison function.
- [SortedStableFunc](/pkg/slices#SortedStableFunc) is like `SortFunc`
  but uses a stable sort algorithm.
- [Chunk](/pkg/slices#Chunk) returns an iterator over consecutive
  sub-slices of up to n elements of a slice.

The [maps] package adds several functions that work with iterators:
- [All](/pkg/maps#All) returns an iterator over key-value pairs from m.

env GO111MODULE=on

# File system pattern searches should skip sub-modules and vendor directories.
cd x

# all packages
go list all
stdout ^m$
stdout ^m/vendor$
! stdout vendor/
stdout ^m/y$
! stdout ^m/y/z

# path pattern
go list m/...
stdout ^m$
stdout ^m/vendor$
! stdout vendor/
stdout ^m/y$
! stdout ^m/y/z

# directory pattern
go list ./...
stdout ^m$
stdout ^m/vendor$
! stdout vendor/

(F(MADD|NMADD|MSUB|NMSUB)S neg:(FNEGS x) y z) && neg.Uses == 1 => (F(NMSUB|MSUB|NMADD|MADD)S x y z)
(F(MADD|NMADD|MSUB|NMSUB)S x y neg:(FNEGS z)) && neg.Uses == 1 => (F(MSUB|NMSUB|MADD|NMADD)S x y z)
(F(MADD|NMADD|MSUB|NMSUB)D neg:(FNEGD x) y z) && neg.Uses == 1 => (F(NMSUB|MSUB|NMADD|MADD)D x y z)

! go list
stderr -count=1 '^go: sub@v1.0.0: module ./sub requires go >= 1.999 \(running go 1.21\)$'
! go build sub
stderr -count=1 '^go: sub@v1.0.0: module ./sub requires go >= 1.999 \(running go 1.21\)$'

-- go.mod --
module m
go 1.1
require (
	sub v1.0.0
)
replace (
	sub => ./sub
)

-- x.go --
package x

-- sub/go.mod --
module sub
go 1.999

-- sub/x.go --