cmd/compile: trim function name prefix from escape diagnostics

This information is redundant with the position information already
provided. Also, no other -m diagnostics print out function name.

While here, report parameter leak diagnostics against the parameter
declaration position rather than the function, and use Warnl for
"moved to heap" messages.

Test cases updated programmatically by removing the first word from
every "no match for" error emitted by run.go:

go run run.go |& \
  sed -E -n 's/^(.*):(.*): no match for `([^ ]* (.*))` in:$/\1!\2!\3!\4/p' | \
  while IFS='!' read -r fn line before after; do
    before=$(echo "$before" | sed 's/[.[\*^$()+?{|]/\\&/g')
    after=$(echo "$after" | sed -E 's/(\&|\\)/\\&/g')
    fn=$(find . -name "${fn}" | head -1)
    sed -i -E -e "${line}s/\"${before}\"/\"${after}\"/" "${fn}"
  done

Passes toolstash-check.

Change-Id: I6e02486b1409e4a8dbb2b9b816d22095835426b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/195040
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/test/escape_array.go b/test/escape_array.go
index d363b98eac..0d07fd861f 100644
--- a/test/escape_array.go
+++ b/test/escape_array.go
@@ -71,7 +71,7 @@ func fuo(x *U, y *U) *string { // ERROR "leaking param: x to result ~r2 level=1$
 // pointers stored in small array literals do not escape;
 // large array literals are heap allocated;
 // pointers stored in large array literals escape.
-func hugeLeaks1(x **string, y **string) { // ERROR "leaking param content: x" "hugeLeaks1 y does not escape"
+func hugeLeaks1(x **string, y **string) { // ERROR "leaking param content: x" "y does not escape"
 	a := [10]*string{*y}
 	_ = a
 	// 4 x 4,000,000 exceeds MaxStackVarSize, therefore it must be heap allocated if pointers are 4 bytes or larger.
@@ -79,7 +79,7 @@ func hugeLeaks1(x **string, y **string) { // ERROR "leaking param content: x" "h
 	_ = b
 }
 
-func hugeLeaks2(x *string, y *string) { // ERROR "leaking param: x" "hugeLeaks2 y does not escape"
+func hugeLeaks2(x *string, y *string) { // ERROR "leaking param: x" "y does not escape"
 	a := [10]*string{y}
 	_ = a
 	// 4 x 4,000,000 exceeds MaxStackVarSize, therefore it must be heap allocated if pointers are 4 bytes or larger.