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>

1 files changed, 11 insertions, 11 deletions

diff --git a/test/escape_map.go b/test/escape_map.go
index 99cbd482a6..9912b55a35 100644
--- a/test/escape_map.go
+++ b/test/escape_map.go
@@ -16,7 +16,7 @@ func map0() {
 	i := 0 // ERROR "moved to heap: i"
 	// BAD: j should not escape
 	j := 0     // ERROR "moved to heap: j"
-	m[&i] = &j // ERROR "&i escapes to heap" "&j escapes to heap"
+	m[&i] = &j
 	_ = m
 }
 
@@ -25,15 +25,15 @@ func map1() *int {
 	// BAD: i should not escape
 	i := 0       // ERROR "moved to heap: i"
 	j := 0       // ERROR "moved to heap: j"
-	m[&i] = &j   // ERROR "&i escapes to heap" "&j escapes to heap"
-	return m[&i] // ERROR "&i does not escape"
+	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               // ERROR "&i escapes to heap" "&j escapes to heap"
+	m[&i] = &j
 	return m
 }
 
@@ -42,7 +42,7 @@ func map3() []*int {
 	i := 0                   // ERROR "moved to heap: i"
 	// BAD: j should not escape
 	j := 0     // ERROR "moved to heap: j"
-	m[&i] = &j // ERROR "&i escapes to heap" "&j escapes to heap"
+	m[&i] = &j
 	var r []*int
 	for k := range m {
 		r = append(r, k)
@@ -55,7 +55,7 @@ func map4() []*int {
 	// BAD: i should not escape
 	i := 0     // ERROR "moved to heap: i"
 	j := 0     // ERROR "moved to heap: j"
-	m[&i] = &j // ERROR "&i escapes to heap" "&j escapes to heap"
+	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".
@@ -70,7 +70,7 @@ func map4() []*int {
 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 // ERROR "&i escapes to heap" "&j escapes to heap"
+	m[&i] = &j
 }
 
 func map6(m map[*int]*int) { // ERROR "m does not escape"
@@ -79,7 +79,7 @@ func map6(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 // ERROR "&i escapes to heap" "&j escapes to heap"
+	m[&i] = &j
 }
 
 func map7() {
@@ -87,14 +87,14 @@ func map7() {
 	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 "&i escapes to heap" "&j escapes to heap" "literal does not escape"
+	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 "&i escapes to heap" "&j escapes to heap" "literal escapes to heap"
+	m := map[*int]*int{&i: &j} // ERROR "literal escapes to heap"
 	sink = m // ERROR "m escapes to heap"
 }
 
@@ -102,6 +102,6 @@ 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 "&i escapes to heap" "&j escapes to heap" "literal does not escape"
+	m := map[*int]*int{&i: &j} // ERROR "literal does not escape"
 	return m[nil]
 }