podman

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// Copyright 2015 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package objabi
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import (
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	"fmt"
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	"log"
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	"os"
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	"strings"
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)
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func envOr(key, value string) string {
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	if x := os.Getenv(key); x != "" {
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		return x
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	}
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	return value
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}
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var (
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	defaultGOROOT string // set by linker
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	GOROOT   = envOr("GOROOT", defaultGOROOT)
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	GOARCH   = envOr("GOARCH", "amd64")
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	GOOS     = envOr("GOOS", "linux")
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	GO386    = envOr("GO386", "")
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	GOAMD64  = goamd64()
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	GOARM    = goarm()
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	GOMIPS   = gomips()
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	GOMIPS64 = gomips64()
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	GOPPC64  = goppc64()
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	GOWASM   = gowasm()
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	GO_LDSO  = ""
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	Version  = ""
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)
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const (
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	ElfRelocOffset   = 256
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	MachoRelocOffset = 2048           // reserve enough space for ELF relocations
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	Go115AMD64       = "alignedjumps" // Should be "alignedjumps" or "normaljumps"; this replaces environment variable introduced in CL 219357.
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)
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// TODO(1.16): assuming no issues in 1.15 release, remove this and related constant.
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func goamd64() string {
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	return Go115AMD64
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}
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func goarm() int {
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	switch v := envOr("GOARM", "7"); v {
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	case "5":
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		return 5
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	case "6":
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		return 6
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	case "7":
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		return 7
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	}
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	// Fail here, rather than validate at multiple call sites.
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	log.Fatalf("Invalid GOARM value. Must be 5, 6, or 7.")
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	panic("unreachable")
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}
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func gomips() string {
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	switch v := envOr("GOMIPS", "hardfloat"); v {
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	case "hardfloat", "softfloat":
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		return v
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	}
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	log.Fatalf("Invalid GOMIPS value. Must be hardfloat or softfloat.")
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	panic("unreachable")
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}
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func gomips64() string {
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	switch v := envOr("GOMIPS64", "hardfloat"); v {
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	case "hardfloat", "softfloat":
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		return v
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	}
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	log.Fatalf("Invalid GOMIPS64 value. Must be hardfloat or softfloat.")
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	panic("unreachable")
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}
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func goppc64() int {
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	switch v := envOr("GOPPC64", "power8"); v {
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	case "power8":
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		return 8
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	case "power9":
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		return 9
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	}
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	log.Fatalf("Invalid GOPPC64 value. Must be power8 or power9.")
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	panic("unreachable")
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}
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type gowasmFeatures struct {
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	SignExt bool
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	SatConv bool
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}
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func (f gowasmFeatures) String() string {
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	var flags []string
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	if f.SatConv {
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		flags = append(flags, "satconv")
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	}
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	if f.SignExt {
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		flags = append(flags, "signext")
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	}
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	return strings.Join(flags, ",")
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}
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func gowasm() (f gowasmFeatures) {
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	for _, opt := range strings.Split(envOr("GOWASM", ""), ",") {
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		switch opt {
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		case "satconv":
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			f.SatConv = true
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		case "signext":
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			f.SignExt = true
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		case "":
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			// ignore
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		default:
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			log.Fatalf("Invalid GOWASM value. No such feature: " + opt)
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		}
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	}
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	return
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}
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func Getgoextlinkenabled() string {
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	return envOr("GO_EXTLINK_ENABLED", "")
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}
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func init() {
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	for _, f := range strings.Split("", ",") {
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		if f != "" {
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			addexp(f)
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		}
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	}
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	// regabi is only supported on amd64.
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	if GOARCH != "amd64" {
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		Regabi_enabled = 0
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	}
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}
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// Note: must agree with runtime.framepointer_enabled.
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var Framepointer_enabled = GOARCH == "amd64" || GOARCH == "arm64" && (GOOS == "linux" || GOOS == "darwin")
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func addexp(s string) {
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	// Could do general integer parsing here, but the runtime copy doesn't yet.
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	v := 1
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	name := s
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	if len(name) > 2 && name[:2] == "no" {
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		v = 0
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		name = name[2:]
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	}
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	for i := 0; i < len(exper); i++ {
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		if exper[i].name == name {
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			if exper[i].val != nil {
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				*exper[i].val = v
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			}
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			return
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		}
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	}
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	fmt.Printf("unknown experiment %s\n", s)
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	os.Exit(2)
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}
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var (
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	Fieldtrack_enabled        int
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	Preemptibleloops_enabled  int
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	Staticlockranking_enabled int
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	Regabi_enabled            int
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)
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// Toolchain experiments.
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// These are controlled by the GOEXPERIMENT environment
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// variable recorded when the toolchain is built.
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// This list is also known to cmd/gc.
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var exper = []struct {
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	name string
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	val  *int
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}{
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	{"fieldtrack", &Fieldtrack_enabled},
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	{"preemptibleloops", &Preemptibleloops_enabled},
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	{"staticlockranking", &Staticlockranking_enabled},
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	{"regabi", &Regabi_enabled},
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}
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var defaultExpstring = Expstring()
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func DefaultExpstring() string {
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	return defaultExpstring
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}
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func Expstring() string {
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	buf := "X"
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	for i := range exper {
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		if *exper[i].val != 0 {
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			buf += "," + exper[i].name
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		}
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	}
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	if buf == "X" {
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		buf += ",none"
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	}
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	return "X:" + buf[2:]
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}
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