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go/test/escape_map.go
Matthew Dempsky abefcac10a cmd/compile: skip escape analysis diagnostics for OADDR
For most nodes (e.g., OPTRLIT, OMAKESLICE, OCONVIFACE), escape
analysis prints "escapes to heap" or "does not escape" to indicate
whether that node's allocation can be heap or stack allocated.

These messages are also emitted for OADDR, even though OADDR does not
actually allocate anything itself. Moreover, it's redundant because
escape analysis already prints "moved to heap" diagnostics when an
OADDR node like "&x" causes x to require heap allocation.

Because OADDR nodes don't allocate memory, my escape analysis rewrite
doesn't naturally emit the "escapes to heap" / "does not escape"
diagnostics for them. It's also non-trivial to replicate the exact
semantics esc.go uses for OADDR.

Since there are so many of these messages, I'm disabling them in this
CL by themselves. I modified esc.go to suppress the Warnl calls
without any other behavior changes, and then used a shell script to
automatically remove any ERROR messages mentioned by run.go in
"missing error" or "no match for" lines.

Fixes #16300.
Updates #23109.

Change-Id: I3993e2743c3ff83ccd0893f4e73b366ff8871a57
Reviewed-on: https://go-review.googlesource.com/c/go/+/170319
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
2019-04-02 16:34:03 +00:00

108 lines
2.8 KiB
Go

// errorcheck -0 -m -l
// Copyright 2015 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.
// Test escape analysis for maps.
package escape
var sink interface{}
func map0() {
m := make(map[*int]*int) // ERROR "make\(map\[\*int\]\*int\) does not escape"
// BAD: i should not escape
i := 0 // ERROR "moved to heap: i"
// BAD: j should not escape
j := 0 // ERROR "moved to heap: j"
m[&i] = &j
_ = m
}
func map1() *int {
m := make(map[*int]*int) // ERROR "make\(map\[\*int\]\*int\) does not escape"
// BAD: i should not escape
i := 0 // ERROR "moved to heap: i"
j := 0 // ERROR "moved to heap: j"
m[&i] = &j
return m[&i]
}
func map2() map[*int]*int {
m := make(map[*int]*int) // ERROR "make\(map\[\*int\]\*int\) escapes to heap"
i := 0 // ERROR "moved to heap: i"
j := 0 // ERROR "moved to heap: j"
m[&i] = &j
return m
}
func map3() []*int {
m := make(map[*int]*int) // ERROR "make\(map\[\*int\]\*int\) does not escape"
i := 0 // ERROR "moved to heap: i"
// BAD: j should not escape
j := 0 // ERROR "moved to heap: j"
m[&i] = &j
var r []*int
for k := range m {
r = append(r, k)
}
return r
}
func map4() []*int {
m := make(map[*int]*int) // ERROR "make\(map\[\*int\]\*int\) does not escape"
// BAD: i should not escape
i := 0 // ERROR "moved to heap: i"
j := 0 // ERROR "moved to heap: j"
m[&i] = &j
var r []*int
for k, v := range m {
// We want to test exactly "for k, v := range m" rather than "for _, v := range m".
// The following if is merely to use (but not leak) k.
if k != nil {
r = append(r, v)
}
}
return r
}
func map5(m map[*int]*int) { // ERROR "m does not escape"
i := 0 // ERROR "moved to heap: i"
j := 0 // ERROR "moved to heap: j"
m[&i] = &j
}
func map6(m map[*int]*int) { // ERROR "m does not escape"
if m != nil {
m = make(map[*int]*int) // ERROR "make\(map\[\*int\]\*int\) does not escape"
}
i := 0 // ERROR "moved to heap: i"
j := 0 // ERROR "moved to heap: j"
m[&i] = &j
}
func map7() {
// BAD: i should not escape
i := 0 // ERROR "moved to heap: i"
// BAD: j should not escape
j := 0 // ERROR "moved to heap: j"
m := map[*int]*int{&i: &j} // ERROR "literal does not escape"
_ = m
}
func map8() {
i := 0 // ERROR "moved to heap: i"
j := 0 // ERROR "moved to heap: j"
m := map[*int]*int{&i: &j} // ERROR "literal escapes to heap"
sink = m // ERROR "m escapes to heap"
}
func map9() *int {
// BAD: i should not escape
i := 0 // ERROR "moved to heap: i"
j := 0 // ERROR "moved to heap: j"
m := map[*int]*int{&i: &j} // ERROR "literal does not escape"
return m[nil]
}