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, 1 insertions, 1 deletions

diff --git a/test/escape_iface.go b/test/escape_iface.go
index be7b6024cd..898f504b31 100644
--- a/test/escape_iface.go
+++ b/test/escape_iface.go
@@ -110,7 +110,7 @@ func efaceEscape1() {
 	{
 		i := 0         // ERROR "moved to heap: i"
 		v := M1{&i, 0}
-		var x M = v // ERROR "efaceEscape1 v does not escape"
+		var x M = v // ERROR "v does not escape"
 		v1 := x.(M1)
 		sink = v1 // ERROR "v1 escapes to heap"
 	}