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go/test/live.go
Keith Randall 442de98c14 cmd/compile,runtime: redo how map assignments work
To compile:
  m[k] = v
instead of:
  mapassign(maptype, m, &k, &v), do
do:
  *mapassign(maptype, m, &k) = v

mapassign returns a pointer to the value slot in the map.  It is just
like mapaccess except that it will allocate a new slot if k is not
already present in the map.

This makes map accesses faster but potentially larger (codewise).

It is faster because the write into the map is done when the compiler
knows the concrete type, so it can be done with a few store
instructions instead of calling typedmemmove.  We also potentially
avoid stack temporaries to hold v.

The code can be larger when the map has pointers in its value type,
since there is a write barrier call in addition to the mapassign call.
That makes the code at the callsite a bit bigger (go binary is 0.3%
bigger).

This CL is in preparation for doing operations like m[k] += v with
only a single runtime call.  That will roughly double the speed of
such operations.

Update #17133
Update #5147

Change-Id: Ia435f032090a2ed905dac9234e693972fe8c2dc5
Reviewed-on: https://go-review.googlesource.com/30815
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-12 20:41:23 +00:00

670 lines
19 KiB
Go

// errorcheckwithauto -0 -l -live -wb=0
// +build !ppc64,!ppc64le
// ppc64 needs a better tighten pass to make f18 pass
// Copyright 2014 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.
// liveness tests with inlining disabled.
// see also live2.go.
package main
func printnl()
//go:noescape
func printpointer(**int)
//go:noescape
func printintpointer(*int)
//go:noescape
func printstringpointer(*string)
//go:noescape
func printstring(string)
//go:noescape
func printbytepointer(*byte)
func printint(int)
func f1() {
var x *int
printpointer(&x) // ERROR "live at call to printpointer: x$"
printpointer(&x) // ERROR "live at call to printpointer: x$"
}
func f2(b bool) {
if b {
printint(0) // nothing live here
return
}
var x *int
printpointer(&x) // ERROR "live at call to printpointer: x$"
printpointer(&x) // ERROR "live at call to printpointer: x$"
}
func f3(b1, b2 bool) {
// Here x and y are ambiguously live. In previous go versions they
// were marked as live throughout the function to avoid being
// poisoned in GODEBUG=gcdead=1 mode; this is now no longer the
// case.
printint(0)
if b1 == false {
printint(0)
return
}
if b2 {
var x *int
printpointer(&x) // ERROR "live at call to printpointer: x$"
printpointer(&x) // ERROR "live at call to printpointer: x$"
} else {
var y *int
printpointer(&y) // ERROR "live at call to printpointer: y$"
printpointer(&y) // ERROR "live at call to printpointer: y$"
}
printint(0) // ERROR "f3: x \(type \*int\) is ambiguously live$" "f3: y \(type \*int\) is ambiguously live$" "live at call to printint: x y$"
}
// The old algorithm treated x as live on all code that
// could flow to a return statement, so it included the
// function entry and code above the declaration of x
// but would not include an indirect use of x in an infinite loop.
// Check that these cases are handled correctly.
func f4(b1, b2 bool) { // x not live here
if b2 {
printint(0) // x not live here
return
}
var z **int
x := new(int)
*x = 42
z = &x
printint(**z) // ERROR "live at call to printint: x$"
if b2 {
printint(1) // x not live here
return
}
for {
printint(**z) // ERROR "live at call to printint: x$"
}
}
func f5(b1 bool) {
var z **int
if b1 {
x := new(int)
*x = 42
z = &x
} else {
y := new(int)
*y = 54
z = &y
}
printint(**z) // ERROR "f5: x \(type \*int\) is ambiguously live$" "f5: y \(type \*int\) is ambiguously live$" "live at call to printint: x y$"
}
// confusion about the _ result used to cause spurious "live at entry to f6: _".
func f6() (_, y string) {
y = "hello"
return
}
// confusion about addressed results used to cause "live at entry to f7: x".
func f7() (x string) {
_ = &x
x = "hello"
return
}
// ignoring block returns used to cause "live at entry to f8: x, y".
func f8() (x, y string) {
return g8()
}
func g8() (string, string)
// ignoring block assignments used to cause "live at entry to f9: x"
// issue 7205
var i9 interface{}
func f9() bool {
g8()
x := i9
y := interface{}(99.0i) // ERROR "live at call to convT2E: x.data x.type$"
i9 = y // make y escape so the line above has to call convT2E
return x != y
}
// liveness formerly confused by UNDEF followed by RET,
// leading to "live at entry to f10: ~r1" (unnamed result).
func f10() string {
panic(1)
}
// liveness formerly confused by select, thinking runtime.selectgo
// can return to next instruction; it always jumps elsewhere.
// note that you have to use at least two cases in the select
// to get a true select; smaller selects compile to optimized helper functions.
var c chan *int
var b bool
// this used to have a spurious "live at entry to f11a: ~r0"
func f11a() *int {
select { // ERROR "live at call to newselect: autotmp_[0-9]+$" "live at call to selectgo: autotmp_[0-9]+$"
case <-c: // ERROR "live at call to selectrecv: autotmp_[0-9]+$"
return nil
case <-c: // ERROR "live at call to selectrecv: autotmp_[0-9]+$"
return nil
}
}
func f11b() *int {
p := new(int)
if b {
// At this point p is dead: the code here cannot
// get to the bottom of the function.
// This used to have a spurious "live at call to printint: p".
printint(1) // nothing live here!
select { // ERROR "live at call to newselect: autotmp_[0-9]+$" "live at call to selectgo: autotmp_[0-9]+$"
case <-c: // ERROR "live at call to selectrecv: autotmp_[0-9]+$"
return nil
case <-c: // ERROR "live at call to selectrecv: autotmp_[0-9]+$"
return nil
}
}
println(*p)
return nil
}
var sink *int
func f11c() *int {
p := new(int)
sink = p // prevent stack allocation, otherwise p is rematerializeable
if b {
// Unlike previous, the cases in this select fall through,
// so we can get to the println, so p is not dead.
printint(1) // ERROR "live at call to printint: p$"
select { // ERROR "live at call to newselect: autotmp_[0-9]+ p$" "live at call to selectgo: autotmp_[0-9]+ p$"
case <-c: // ERROR "live at call to selectrecv: autotmp_[0-9]+ p$"
case <-c: // ERROR "live at call to selectrecv: autotmp_[0-9]+ p$"
}
}
println(*p)
return nil
}
// similarly, select{} does not fall through.
// this used to have a spurious "live at entry to f12: ~r0".
func f12() *int {
if b {
select {}
} else {
return nil
}
}
// incorrectly placed VARDEF annotations can cause missing liveness annotations.
// this used to be missing the fact that s is live during the call to g13 (because it is
// needed for the call to h13).
func f13() {
s := g14()
s = h13(s, g13(s)) // ERROR "live at call to g13: s.ptr$"
}
func g13(string) string
func h13(string, string) string
// more incorrectly placed VARDEF.
func f14() {
x := g14()
printstringpointer(&x) // ERROR "live at call to printstringpointer: x$"
}
func g14() string
func f15() {
var x string
_ = &x
x = g15() // ERROR "live at call to g15: x$"
printstring(x) // ERROR "live at call to printstring: x$"
}
func g15() string
// Checking that various temporaries do not persist or cause
// ambiguously live values that must be zeroed.
// The exact temporary names are inconsequential but we are
// trying to check that there is only one at any given site,
// and also that none show up in "ambiguously live" messages.
var m map[string]int
func f16() {
if b {
delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$"
}
delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$"
delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$"
}
var m2s map[string]*byte
var m2 map[[2]string]*byte
var x2 [2]string
var bp *byte
func f17a(p *byte) { // ERROR "live at entry to f17a: p$"
if b {
m2[x2] = p // ERROR "live at call to mapassign: p$"
}
m2[x2] = p // ERROR "live at call to mapassign: p$"
m2[x2] = p // ERROR "live at call to mapassign: p$"
}
func f17b(p *byte) { // ERROR "live at entry to f17b: p$"
// key temporary
if b {
m2s["x"] = p // ERROR "live at call to mapassign: p autotmp_[0-9]+$"
}
m2s["x"] = p // ERROR "live at call to mapassign: p autotmp_[0-9]+$"
m2s["x"] = p // ERROR "live at call to mapassign: p autotmp_[0-9]+$"
}
func f17c() {
// key and value temporaries
if b {
m2s["x"] = f17d() // ERROR "live at call to f17d: autotmp_[0-9]+$" "live at call to mapassign: autotmp_[0-9]+ autotmp_[0-9]+$"
}
m2s["x"] = f17d() // ERROR "live at call to f17d: autotmp_[0-9]+$" "live at call to mapassign: autotmp_[0-9]+ autotmp_[0-9]+$"
m2s["x"] = f17d() // ERROR "live at call to f17d: autotmp_[0-9]+$" "live at call to mapassign: autotmp_[0-9]+ autotmp_[0-9]+$"
}
func f17d() *byte
func g18() [2]string
func f18() {
// key temporary for mapaccess.
// temporary introduced by orderexpr.
var z *byte
if b {
z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
}
z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
printbytepointer(z)
}
var ch chan *byte
func f19() {
// dest temporary for channel receive.
var z *byte
if b {
z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$"
}
z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$"
z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$"
printbytepointer(z)
}
func f20() {
// src temporary for channel send
if b {
ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$"
}
ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$"
ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$"
}
func f21() {
// key temporary for mapaccess using array literal key.
var z *byte
if b {
z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
}
z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
printbytepointer(z)
}
func f23() {
// key temporary for two-result map access using array literal key.
var z *byte
var ok bool
if b {
z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$"
}
z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$"
z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$"
printbytepointer(z)
print(ok)
}
func f24() {
// key temporary for map access using array literal key.
// value temporary too.
if b {
m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign: autotmp_[0-9]+$"
}
m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign: autotmp_[0-9]+$"
m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign: autotmp_[0-9]+$"
}
// defer should not cause spurious ambiguously live variables
func f25(b bool) {
defer g25()
if b {
return
}
var x string
_ = &x
x = g15() // ERROR "live at call to g15: x$"
printstring(x) // ERROR "live at call to printstring: x$"
} // ERROR "live at call to deferreturn: x$"
func g25()
// non-escaping ... slices passed to function call should die on return,
// so that the temporaries do not stack and do not cause ambiguously
// live variables.
func f26(b bool) {
if b {
print26((*int)(nil), (*int)(nil), (*int)(nil)) // ERROR "live at call to print26: autotmp_[0-9]+$"
}
print26((*int)(nil), (*int)(nil), (*int)(nil)) // ERROR "live at call to print26: autotmp_[0-9]+$"
print26((*int)(nil), (*int)(nil), (*int)(nil)) // ERROR "live at call to print26: autotmp_[0-9]+$"
printnl()
}
//go:noescape
func print26(...interface{})
// non-escaping closures passed to function call should die on return
func f27(b bool) {
x := 0
if b {
call27(func() { x++ }) // ERROR "live at call to call27: autotmp_[0-9]+$"
}
call27(func() { x++ }) // ERROR "live at call to call27: autotmp_[0-9]+$"
call27(func() { x++ }) // ERROR "live at call to call27: autotmp_[0-9]+$"
printnl()
}
// but defer does escape to later execution in the function
func f27defer(b bool) {
x := 0
if b {
defer call27(func() { x++ }) // ERROR "live at call to deferproc: autotmp_[0-9]+$" "live at call to deferreturn: autotmp_[0-9]+$"
}
defer call27(func() { x++ }) // ERROR "f27defer: autotmp_[0-9]+ \(type struct { F uintptr; x \*int }\) is ambiguously live$" "live at call to deferproc: autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to deferreturn: autotmp_[0-9]+ autotmp_[0-9]+$"
printnl() // ERROR "live at call to printnl: autotmp_[0-9]+ autotmp_[0-9]+$"
} // ERROR "live at call to deferreturn: autotmp_[0-9]+ autotmp_[0-9]+$"
// and newproc (go) escapes to the heap
func f27go(b bool) {
x := 0
if b {
go call27(func() { x++ }) // ERROR "live at call to newobject: &x$" "live at call to newproc: &x$"
}
go call27(func() { x++ }) // ERROR "live at call to newobject: &x$"
printnl()
}
//go:noescape
func call27(func())
// concatstring slice should die on return
var s1, s2, s3, s4, s5, s6, s7, s8, s9, s10 string
func f28(b bool) {
if b {
printstring(s1 + s2 + s3 + s4 + s5 + s6 + s7 + s8 + s9 + s10) // ERROR "live at call to concatstrings: autotmp_[0-9]+$" "live at call to printstring: autotmp_[0-9]+$"
}
printstring(s1 + s2 + s3 + s4 + s5 + s6 + s7 + s8 + s9 + s10) // ERROR "live at call to concatstrings: autotmp_[0-9]+$" "live at call to printstring: autotmp_[0-9]+$"
printstring(s1 + s2 + s3 + s4 + s5 + s6 + s7 + s8 + s9 + s10) // ERROR "live at call to concatstrings: autotmp_[0-9]+$" "live at call to printstring: autotmp_[0-9]+$"
}
// map iterator should die on end of range loop
func f29(b bool) {
if b {
for k := range m { // ERROR "live at call to mapiterinit: autotmp_[0-9]+$" "live at call to mapiternext: autotmp_[0-9]+$"
printstring(k) // ERROR "live at call to printstring: autotmp_[0-9]+$"
}
}
for k := range m { // ERROR "live at call to mapiterinit: autotmp_[0-9]+$" "live at call to mapiternext: autotmp_[0-9]+$"
printstring(k) // ERROR "live at call to printstring: autotmp_[0-9]+$"
}
for k := range m { // ERROR "live at call to mapiterinit: autotmp_[0-9]+$" "live at call to mapiternext: autotmp_[0-9]+$"
printstring(k) // ERROR "live at call to printstring: autotmp_[0-9]+$"
}
}
// copy of array of pointers should die at end of range loop
var ptrarr [10]*int
func f30(b bool) {
// two live temps during print(p):
// the copy of ptrarr and the internal iterator pointer.
if b {
for _, p := range ptrarr {
printintpointer(p) // ERROR "live at call to printintpointer: autotmp_[0-9]+ autotmp_[0-9]+$"
}
}
for _, p := range ptrarr {
printintpointer(p) // ERROR "live at call to printintpointer: autotmp_[0-9]+ autotmp_[0-9]+$"
}
for _, p := range ptrarr {
printintpointer(p) // ERROR "live at call to printintpointer: autotmp_[0-9]+ autotmp_[0-9]+$"
}
}
// conversion to interface should not leave temporary behind
func f31(b1, b2, b3 bool) {
if b1 {
g31("a") // ERROR "live at call to convT2E: autotmp_[0-9]+$" "live at call to g31: autotmp_[0-9]+$"
}
if b2 {
h31("b") // ERROR "live at call to convT2E: autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to h31: autotmp_[0-9]+$" "live at call to newobject: autotmp_[0-9]+$"
}
if b3 {
panic("asdf") // ERROR "live at call to convT2E: autotmp_[0-9]+$" "live at call to gopanic: autotmp_[0-9]+$"
}
print(b3)
}
func g31(interface{})
func h31(...interface{})
// non-escaping partial functions passed to function call should die on return
type T32 int
func (t *T32) Inc() { // ERROR "live at entry to \(\*T32\).Inc: t$"
*t++
}
var t32 T32
func f32(b bool) {
if b {
call32(t32.Inc) // ERROR "live at call to call32: autotmp_[0-9]+$"
}
call32(t32.Inc) // ERROR "live at call to call32: autotmp_[0-9]+$"
call32(t32.Inc) // ERROR "live at call to call32: autotmp_[0-9]+$"
}
//go:noescape
func call32(func())
// temporaries introduced during if conditions and && || expressions
// should die once the condition has been acted upon.
var m33 map[interface{}]int
func f33() {
if m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
printnl()
return
} else {
printnl()
}
printnl()
}
func f34() {
if m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
printnl()
return
}
printnl()
}
func f35() {
if m33[nil] == 0 && m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
printnl()
return
}
printnl()
}
func f36() {
if m33[nil] == 0 || m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
printnl()
return
}
printnl()
}
func f37() {
if (m33[nil] == 0 || m33[nil] == 0) && m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
printnl()
return
}
printnl()
}
// select temps should disappear in the case bodies
var c38 chan string
func fc38() chan string
func fi38(int) *string
func fb38() *bool
func f38(b bool) {
// we don't care what temps are printed on the lines with output.
// we care that the println lines have no live variables
// and therefore no output.
if b {
select { // ERROR "live at call to newselect: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to selectgo: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$"
case <-fc38(): // ERROR "live at call to selectrecv: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$"
printnl()
case fc38() <- *fi38(1): // ERROR "live at call to fc38: autotmp_[0-9]+$" "live at call to fi38: autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to selectsend: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$"
printnl()
case *fi38(2) = <-fc38(): // ERROR "live at call to fc38: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to fi38: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to selectrecv: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$"
printnl()
case *fi38(3), *fb38() = <-fc38(): // ERROR "live at call to fb38: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to fc38: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to fi38: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to selectrecv2: autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+ autotmp_[0-9]+$"
printnl()
}
printnl()
}
printnl()
}
// issue 8097: mishandling of x = x during return.
func f39() (x []int) {
x = []int{1}
printnl() // ERROR "live at call to printnl: autotmp_[0-9]+$"
return x
}
func f39a() (x []int) {
x = []int{1}
printnl() // ERROR "live at call to printnl: autotmp_[0-9]+$"
return
}
func f39b() (x [10]*int) {
x = [10]*int{}
x[0] = new(int) // ERROR "live at call to newobject: x$"
printnl() // ERROR "live at call to printnl: x$"
return x
}
func f39c() (x [10]*int) {
x = [10]*int{}
x[0] = new(int) // ERROR "live at call to newobject: x$"
printnl() // ERROR "live at call to printnl: x$"
return
}
// issue 8142: lost 'addrtaken' bit on inlined variables.
// no inlining in this test, so just checking that non-inlined works.
type T40 struct {
m map[int]int
}
func newT40() *T40 {
ret := T40{}
ret.m = make(map[int]int) // ERROR "live at call to makemap: &ret$"
return &ret
}
func bad40() {
t := newT40()
_ = t
printnl()
}
func good40() {
ret := T40{}
ret.m = make(map[int]int) // ERROR "live at call to makemap: autotmp_[0-9]+ ret$"
t := &ret
printnl() // ERROR "live at call to printnl: autotmp_[0-9]+ ret$"
_ = t
}
func ddd1(x, y *int) { // ERROR "live at entry to ddd1: x y$"
ddd2(x, y) // ERROR "live at call to ddd2: autotmp_[0-9]+$"
printnl()
// Note: no autotmp live at printnl. See issue 16996.
}
func ddd2(a ...*int) { // ERROR "live at entry to ddd2: a$"
sink = a[0]
}
// issue 16016: autogenerated wrapper should have arguments live
type T struct{}
func (*T) Foo(ptr *int) {}
type R struct{ *T } // ERRORAUTO "live at entry to \(\*R\)\.Foo: \.this ptr" "live at entry to R\.Foo: \.this ptr"