1// errorcheckwithauto -0 -l -live -wb=0 -d=ssa/insert_resched_checks/off
2
3//go:build !ppc64 && !ppc64le && !goexperiment.regabiargs
4
5// ppc64 needs a better tighten pass to make f18 pass
6// rescheduling checks need to be turned off because there are some live variables across the inserted check call
7//
8// For register ABI, liveness info changes slightly. See live_regabi.go.
9
10// Copyright 2014 The Go Authors. All rights reserved.
11// Use of this source code is governed by a BSD-style
12// license that can be found in the LICENSE file.
13
14// liveness tests with inlining disabled.
15// see also live2.go.
16
17package main
18
19func printnl()
20
21//go:noescape
22func printpointer(**int)
23
24//go:noescape
25func printintpointer(*int)
26
27//go:noescape
28func printstringpointer(*string)
29
30//go:noescape
31func printstring(string)
32
33//go:noescape
34func printbytepointer(*byte)
35
36func printint(int)
37
38func f1() {
39	var x *int       // ERROR "stack object x \*int$"
40	printpointer(&x) // ERROR "live at call to printpointer: x$"
41	printpointer(&x)
42}
43
44func f2(b bool) {
45	if b {
46		printint(0) // nothing live here
47		return
48	}
49	var x *int       // ERROR "stack object x \*int$"
50	printpointer(&x) // ERROR "live at call to printpointer: x$"
51	printpointer(&x)
52}
53
54func f3(b1, b2 bool) {
55	// Here x and y are ambiguously live. In previous go versions they
56	// were marked as live throughout the function to avoid being
57	// poisoned in GODEBUG=gcdead=1 mode; this is now no longer the
58	// case.
59
60	printint(0)
61	if b1 == false {
62		printint(0)
63		return
64	}
65
66	if b2 {
67		var x *int       // ERROR "stack object x \*int$"
68		printpointer(&x) // ERROR "live at call to printpointer: x$"
69		printpointer(&x)
70	} else {
71		var y *int       // ERROR "stack object y \*int$"
72		printpointer(&y) // ERROR "live at call to printpointer: y$"
73		printpointer(&y)
74	}
75	printint(0) // nothing is live here
76}
77
78// The old algorithm treated x as live on all code that
79// could flow to a return statement, so it included the
80// function entry and code above the declaration of x
81// but would not include an indirect use of x in an infinite loop.
82// Check that these cases are handled correctly.
83
84func f4(b1, b2 bool) { // x not live here
85	if b2 {
86		printint(0) // x not live here
87		return
88	}
89	var z **int
90	x := new(int) // ERROR "stack object x \*int$"
91	*x = 42
92	z = &x
93	printint(**z) // ERROR "live at call to printint: x$"
94	if b2 {
95		printint(1) // x not live here
96		return
97	}
98	for {
99		printint(**z) // ERROR "live at call to printint: x$"
100	}
101}
102
103func f5(b1 bool) {
104	var z **int
105	if b1 {
106		x := new(int) // ERROR "stack object x \*int$"
107		*x = 42
108		z = &x
109	} else {
110		y := new(int) // ERROR "stack object y \*int$"
111		*y = 54
112		z = &y
113	}
114	printint(**z) // nothing live here
115}
116
117// confusion about the _ result used to cause spurious "live at entry to f6: _".
118
119func f6() (_, y string) {
120	y = "hello"
121	return
122}
123
124// confusion about addressed results used to cause "live at entry to f7: x".
125
126func f7() (x string) { // ERROR "stack object x string"
127	_ = &x
128	x = "hello"
129	return
130}
131
132// ignoring block returns used to cause "live at entry to f8: x, y".
133
134func f8() (x, y string) {
135	return g8()
136}
137
138func g8() (string, string)
139
140// ignoring block assignments used to cause "live at entry to f9: x"
141// issue 7205
142
143var i9 interface{}
144
145func f9() bool {
146	g8()
147	x := i9
148	y := interface{}(g18()) // ERROR "live at call to convT: x.data$" "live at call to g18: x.data$" "stack object .autotmp_[0-9]+ \[2\]string$"
149	i9 = y                  // make y escape so the line above has to call convT
150	return x != y
151}
152
153// liveness formerly confused by UNDEF followed by RET,
154// leading to "live at entry to f10: ~r1" (unnamed result).
155
156func f10() string {
157	panic(1)
158}
159
160// liveness formerly confused by select, thinking runtime.selectgo
161// can return to next instruction; it always jumps elsewhere.
162// note that you have to use at least two cases in the select
163// to get a true select; smaller selects compile to optimized helper functions.
164
165var c chan *int
166var b bool
167
168// this used to have a spurious "live at entry to f11a: ~r0"
169func f11a() *int {
170	select { // ERROR "stack object .autotmp_[0-9]+ \[2\]runtime.scase$"
171	case <-c:
172		return nil
173	case <-c:
174		return nil
175	}
176}
177
178func f11b() *int {
179	p := new(int)
180	if b {
181		// At this point p is dead: the code here cannot
182		// get to the bottom of the function.
183		// This used to have a spurious "live at call to printint: p".
184		printint(1) // nothing live here!
185		select {    // ERROR "stack object .autotmp_[0-9]+ \[2\]runtime.scase$"
186		case <-c:
187			return nil
188		case <-c:
189			return nil
190		}
191	}
192	println(*p)
193	return nil
194}
195
196var sink *int
197
198func f11c() *int {
199	p := new(int)
200	sink = p // prevent stack allocation, otherwise p is rematerializeable
201	if b {
202		// Unlike previous, the cases in this select fall through,
203		// so we can get to the println, so p is not dead.
204		printint(1) // ERROR "live at call to printint: p$"
205		select {    // ERROR "live at call to selectgo: p$" "stack object .autotmp_[0-9]+ \[2\]runtime.scase$"
206		case <-c:
207		case <-c:
208		}
209	}
210	println(*p)
211	return nil
212}
213
214// similarly, select{} does not fall through.
215// this used to have a spurious "live at entry to f12: ~r0".
216
217func f12() *int {
218	if b {
219		select {}
220	} else {
221		return nil
222	}
223}
224
225// incorrectly placed VARDEF annotations can cause missing liveness annotations.
226// this used to be missing the fact that s is live during the call to g13 (because it is
227// needed for the call to h13).
228
229func f13() {
230	s := g14()
231	s = h13(s, g13(s)) // ERROR "live at call to g13: s.ptr$"
232}
233
234func g13(string) string
235func h13(string, string) string
236
237// more incorrectly placed VARDEF.
238
239func f14() {
240	x := g14() // ERROR "stack object x string$"
241	printstringpointer(&x)
242}
243
244func g14() string
245
246// Checking that various temporaries do not persist or cause
247// ambiguously live values that must be zeroed.
248// The exact temporary names are inconsequential but we are
249// trying to check that there is only one at any given site,
250// and also that none show up in "ambiguously live" messages.
251
252var m map[string]int
253var mi map[interface{}]int
254
255// str and iface are used to ensure that a temp is required for runtime calls below.
256func str() string
257func iface() interface{}
258
259func f16() {
260	if b {
261		delete(mi, iface()) // ERROR "stack object .autotmp_[0-9]+ interface \{\}$"
262	}
263	delete(mi, iface())
264	delete(mi, iface())
265}
266
267var m2s map[string]*byte
268var m2 map[[2]string]*byte
269var x2 [2]string
270var bp *byte
271
272func f17a(p *byte) { // ERROR "live at entry to f17a: p$"
273	if b {
274		m2[x2] = p // ERROR "live at call to mapassign: p$"
275	}
276	m2[x2] = p // ERROR "live at call to mapassign: p$"
277	m2[x2] = p // ERROR "live at call to mapassign: p$"
278}
279
280func f17b(p *byte) { // ERROR "live at entry to f17b: p$"
281	// key temporary
282	if b {
283		m2s[str()] = p // ERROR "live at call to mapassign_faststr: p$" "live at call to str: p$"
284	}
285	m2s[str()] = p // ERROR "live at call to mapassign_faststr: p$" "live at call to str: p$"
286	m2s[str()] = p // ERROR "live at call to mapassign_faststr: p$" "live at call to str: p$"
287}
288
289func f17c() {
290	// key and value temporaries
291	if b {
292		m2s[str()] = f17d() // ERROR "live at call to f17d: .autotmp_[0-9]+$" "live at call to mapassign_faststr: .autotmp_[0-9]+$"
293	}
294	m2s[str()] = f17d() // ERROR "live at call to f17d: .autotmp_[0-9]+$" "live at call to mapassign_faststr: .autotmp_[0-9]+$"
295	m2s[str()] = f17d() // ERROR "live at call to f17d: .autotmp_[0-9]+$" "live at call to mapassign_faststr: .autotmp_[0-9]+$"
296}
297
298func f17d() *byte
299
300func g18() [2]string
301
302func f18() {
303	// key temporary for mapaccess.
304	// temporary introduced by orderexpr.
305	var z *byte
306	if b {
307		z = m2[g18()] // ERROR "stack object .autotmp_[0-9]+ \[2\]string$"
308	}
309	z = m2[g18()]
310	z = m2[g18()]
311	printbytepointer(z)
312}
313
314var ch chan *byte
315
316// byteptr is used to ensure that a temp is required for runtime calls below.
317func byteptr() *byte
318
319func f19() {
320	// dest temporary for channel receive.
321	var z *byte
322
323	if b {
324		z = <-ch // ERROR "stack object .autotmp_[0-9]+ \*byte$"
325	}
326	z = <-ch
327	z = <-ch // ERROR "live at call to chanrecv1: .autotmp_[0-9]+$"
328	printbytepointer(z)
329}
330
331func f20() {
332	// src temporary for channel send
333	if b {
334		ch <- byteptr() // ERROR "stack object .autotmp_[0-9]+ \*byte$"
335	}
336	ch <- byteptr()
337	ch <- byteptr()
338}
339
340func f21() {
341	// key temporary for mapaccess using array literal key.
342	var z *byte
343	if b {
344		z = m2[[2]string{"x", "y"}] // ERROR "stack object .autotmp_[0-9]+ \[2\]string$"
345	}
346	z = m2[[2]string{"x", "y"}]
347	z = m2[[2]string{"x", "y"}]
348	printbytepointer(z)
349}
350
351func f23() {
352	// key temporary for two-result map access using array literal key.
353	var z *byte
354	var ok bool
355	if b {
356		z, ok = m2[[2]string{"x", "y"}] // ERROR "stack object .autotmp_[0-9]+ \[2\]string$"
357	}
358	z, ok = m2[[2]string{"x", "y"}]
359	z, ok = m2[[2]string{"x", "y"}]
360	printbytepointer(z)
361	print(ok)
362}
363
364func f24() {
365	// key temporary for map access using array literal key.
366	// value temporary too.
367	if b {
368		m2[[2]string{"x", "y"}] = nil // ERROR "stack object .autotmp_[0-9]+ \[2\]string$"
369	}
370	m2[[2]string{"x", "y"}] = nil
371	m2[[2]string{"x", "y"}] = nil
372}
373
374// Non-open-coded defers should not cause autotmps.  (Open-coded defers do create extra autotmps).
375func f25(b bool) {
376	for i := 0; i < 2; i++ {
377		// Put in loop to make sure defer is not open-coded
378		defer g25()
379	}
380	if b {
381		return
382	}
383	var x string
384	x = g14()
385	printstring(x)
386	return
387}
388
389func g25()
390
391// non-escaping ... slices passed to function call should die on return,
392// so that the temporaries do not stack and do not cause ambiguously
393// live variables.
394
395func f26(b bool) {
396	if b {
397		print26((*int)(nil), (*int)(nil), (*int)(nil)) // ERROR "stack object .autotmp_[0-9]+ \[3\]interface \{\}$"
398	}
399	print26((*int)(nil), (*int)(nil), (*int)(nil))
400	print26((*int)(nil), (*int)(nil), (*int)(nil))
401	printnl()
402}
403
404//go:noescape
405func print26(...interface{})
406
407// non-escaping closures passed to function call should die on return
408
409func f27(b bool) {
410	x := 0
411	if b {
412		call27(func() { x++ }) // ERROR "stack object .autotmp_[0-9]+ struct \{"
413	}
414	call27(func() { x++ })
415	call27(func() { x++ })
416	printnl()
417}
418
419// but defer does escape to later execution in the function
420
421func f27defer(b bool) {
422	x := 0
423	if b {
424		defer call27(func() { x++ }) // ERROR "stack object .autotmp_[0-9]+ struct \{"
425	}
426	defer call27(func() { x++ }) // ERROR "stack object .autotmp_[0-9]+ struct \{"
427	printnl()                    // ERROR "live at call to printnl: .autotmp_[0-9]+ .autotmp_[0-9]+"
428	return                       // ERROR "live at indirect call: .autotmp_[0-9]+"
429}
430
431// and newproc (go) escapes to the heap
432
433func f27go(b bool) {
434	x := 0
435	if b {
436		go call27(func() { x++ }) // ERROR "live at call to newobject: &x$" "live at call to newobject: &x .autotmp_[0-9]+$" "live at call to newproc: &x$" // allocate two closures, the func literal, and the wrapper for go
437	}
438	go call27(func() { x++ }) // ERROR "live at call to newobject: &x$" "live at call to newobject: .autotmp_[0-9]+$" // allocate two closures, the func literal, and the wrapper for go
439	printnl()
440}
441
442//go:noescape
443func call27(func())
444
445// concatstring slice should die on return
446
447var s1, s2, s3, s4, s5, s6, s7, s8, s9, s10 string
448
449func f28(b bool) {
450	if b {
451		printstring(s1 + s2 + s3 + s4 + s5 + s6 + s7 + s8 + s9 + s10) // ERROR "stack object .autotmp_[0-9]+ \[10\]string$"
452	}
453	printstring(s1 + s2 + s3 + s4 + s5 + s6 + s7 + s8 + s9 + s10)
454	printstring(s1 + s2 + s3 + s4 + s5 + s6 + s7 + s8 + s9 + s10)
455}
456
457// map iterator should die on end of range loop
458
459func f29(b bool) {
460	if b {
461		for k := range m { // ERROR "live at call to mapiterinit: .autotmp_[0-9]+$" "live at call to mapiternext: .autotmp_[0-9]+$" "stack object .autotmp_[0-9]+ runtime.hiter$"
462			printstring(k) // ERROR "live at call to printstring: .autotmp_[0-9]+$"
463		}
464	}
465	for k := range m { // ERROR "live at call to mapiterinit: .autotmp_[0-9]+$" "live at call to mapiternext: .autotmp_[0-9]+$"
466		printstring(k) // ERROR "live at call to printstring: .autotmp_[0-9]+$"
467	}
468	for k := range m { // ERROR "live at call to mapiterinit: .autotmp_[0-9]+$" "live at call to mapiternext: .autotmp_[0-9]+$"
469		printstring(k) // ERROR "live at call to printstring: .autotmp_[0-9]+$"
470	}
471}
472
473// copy of array of pointers should die at end of range loop
474var pstructarr [10]pstruct
475
476// Struct size chosen to make pointer to element in pstructarr
477// not computable by strength reduction.
478type pstruct struct {
479	intp *int
480	_    [8]byte
481}
482
483func f30(b bool) {
484	// live temp during printintpointer(p):
485	// the internal iterator pointer if a pointer to pstruct in pstructarr
486	// can not be easily computed by strength reduction.
487	if b {
488		for _, p := range pstructarr { // ERROR "stack object .autotmp_[0-9]+ \[10\]pstruct$"
489			printintpointer(p.intp) // ERROR "live at call to printintpointer: .autotmp_[0-9]+$"
490		}
491	}
492	for _, p := range pstructarr {
493		printintpointer(p.intp) // ERROR "live at call to printintpointer: .autotmp_[0-9]+$"
494	}
495	for _, p := range pstructarr {
496		printintpointer(p.intp) // ERROR "live at call to printintpointer: .autotmp_[0-9]+$"
497	}
498}
499
500// conversion to interface should not leave temporary behind
501
502func f31(b1, b2, b3 bool) {
503	if b1 {
504		g31(g18()) // ERROR "stack object .autotmp_[0-9]+ \[2\]string$"
505	}
506	if b2 {
507		h31(g18()) // ERROR "live at call to convT: .autotmp_[0-9]+$" "live at call to newobject: .autotmp_[0-9]+$"
508	}
509	if b3 {
510		panic(g18())
511	}
512	print(b3)
513}
514
515func g31(interface{})
516func h31(...interface{})
517
518// non-escaping partial functions passed to function call should die on return
519
520type T32 int
521
522func (t *T32) Inc() { // ERROR "live at entry to \(\*T32\).Inc: t$"
523	*t++
524}
525
526var t32 T32
527
528func f32(b bool) {
529	if b {
530		call32(t32.Inc) // ERROR "stack object .autotmp_[0-9]+ struct \{"
531	}
532	call32(t32.Inc)
533	call32(t32.Inc)
534}
535
536//go:noescape
537func call32(func())
538
539// temporaries introduced during if conditions and && || expressions
540// should die once the condition has been acted upon.
541
542var m33 map[interface{}]int
543
544func f33() {
545	if m33[byteptr()] == 0 { // ERROR "stack object .autotmp_[0-9]+ interface \{\}$"
546		printnl()
547		return
548	} else {
549		printnl()
550	}
551	printnl()
552}
553
554func f34() {
555	if m33[byteptr()] == 0 { // ERROR "stack object .autotmp_[0-9]+ interface \{\}$"
556		printnl()
557		return
558	}
559	printnl()
560}
561
562func f35() {
563	if m33[byteptr()] == 0 && // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
564		m33[byteptr()] == 0 { // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
565		printnl()
566		return
567	}
568	printnl()
569}
570
571func f36() {
572	if m33[byteptr()] == 0 || // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
573		m33[byteptr()] == 0 { // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
574		printnl()
575		return
576	}
577	printnl()
578}
579
580func f37() {
581	if (m33[byteptr()] == 0 || // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
582		m33[byteptr()] == 0) && // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
583		m33[byteptr()] == 0 {
584		printnl()
585		return
586	}
587	printnl()
588}
589
590// select temps should disappear in the case bodies
591
592var c38 chan string
593
594func fc38() chan string
595func fi38(int) *string
596func fb38() *bool
597
598func f38(b bool) {
599	// we don't care what temps are printed on the lines with output.
600	// we care that the println lines have no live variables
601	// and therefore no output.
602	if b {
603		select { // ERROR "live at call to selectgo:( .autotmp_[0-9]+)+$" "stack object .autotmp_[0-9]+ \[4\]runtime.scase$"
604		case <-fc38():
605			printnl()
606		case fc38() <- *fi38(1): // ERROR "live at call to fc38:( .autotmp_[0-9]+)+$" "live at call to fi38:( .autotmp_[0-9]+)+$" "stack object .autotmp_[0-9]+ string$"
607			printnl()
608		case *fi38(2) = <-fc38(): // ERROR "live at call to fc38:( .autotmp_[0-9]+)+$" "live at call to fi38:( .autotmp_[0-9]+)+$" "stack object .autotmp_[0-9]+ string$"
609			printnl()
610		case *fi38(3), *fb38() = <-fc38(): // ERROR "stack object .autotmp_[0-9]+ string$" "live at call to f[ibc]38:( .autotmp_[0-9]+)+$"
611			printnl()
612		}
613		printnl()
614	}
615	printnl()
616}
617
618// issue 8097: mishandling of x = x during return.
619
620func f39() (x []int) {
621	x = []int{1}
622	printnl() // ERROR "live at call to printnl: .autotmp_[0-9]+$"
623	return x
624}
625
626func f39a() (x []int) {
627	x = []int{1}
628	printnl() // ERROR "live at call to printnl: .autotmp_[0-9]+$"
629	return
630}
631
632func f39b() (x [10]*int) {
633	x = [10]*int{}
634	x[0] = new(int) // ERROR "live at call to newobject: x$"
635	printnl()       // ERROR "live at call to printnl: x$"
636	return x
637}
638
639func f39c() (x [10]*int) {
640	x = [10]*int{}
641	x[0] = new(int) // ERROR "live at call to newobject: x$"
642	printnl()       // ERROR "live at call to printnl: x$"
643	return
644}
645
646// issue 8142: lost 'addrtaken' bit on inlined variables.
647// no inlining in this test, so just checking that non-inlined works.
648
649type T40 struct {
650	m map[int]int
651}
652
653//go:noescape
654func useT40(*T40)
655
656func newT40() *T40 {
657	ret := T40{}
658	ret.m = make(map[int]int, 42) // ERROR "live at call to makemap: &ret$"
659	return &ret
660}
661
662func bad40() {
663	t := newT40()
664	_ = t
665	printnl()
666}
667
668func good40() {
669	ret := T40{}              // ERROR "stack object ret T40$"
670	ret.m = make(map[int]int) // ERROR "live at call to rand32: .autotmp_[0-9]+$" "stack object .autotmp_[0-9]+ runtime.hmap$"
671	t := &ret
672	printnl() // ERROR "live at call to printnl: ret$"
673	// Note: ret is live at the printnl because the compiler moves &ret
674	// from before the printnl to after.
675	useT40(t)
676}
677
678func ddd1(x, y *int) { // ERROR "live at entry to ddd1: x y$"
679	ddd2(x, y) // ERROR "stack object .autotmp_[0-9]+ \[2\]\*int$"
680	printnl()
681	// Note: no .?autotmp live at printnl.  See issue 16996.
682}
683func ddd2(a ...*int) { // ERROR "live at entry to ddd2: a$"
684	sink = a[0]
685}
686
687// issue 16016: autogenerated wrapper should have arguments live
688type T struct{}
689
690func (*T) Foo(ptr *int) {}
691
692type R struct{ *T }
693
694// issue 18860: output arguments must be live all the time if there is a defer.
695// In particular, at printint r must be live.
696func f41(p, q *int) (r *int) { // ERROR "live at entry to f41: p q$"
697	r = p
698	defer func() {
699		recover()
700	}()
701	printint(0) // ERROR "live at call to printint: .autotmp_[0-9]+ q r$"
702	r = q
703	return // ERROR "live at call to f41.func1: .autotmp_[0-9]+ r$"
704}
705
706func f42() {
707	var p, q, r int
708	f43([]*int{&p, &q, &r}) // ERROR "stack object .autotmp_[0-9]+ \[3\]\*int$"
709	f43([]*int{&p, &r, &q})
710	f43([]*int{&q, &p, &r})
711}
712
713//go:noescape
714func f43(a []*int)
715
716// Assigning to a sub-element that makes up an entire local variable
717// should clobber that variable.
718func f44(f func() [2]*int) interface{} { // ERROR "live at entry to f44: f"
719	type T struct {
720		s [1][2]*int
721	}
722	ret := T{} // ERROR "stack object ret T"
723	ret.s[0] = f()
724	return ret
725}
726