cmd/compile: change the type of ssa Warnl line number

Line numbers are always int32, so the Warnl function should take the
line number as an int32 as well.  This matches gc.Warnl and removes
a cast every place it's used.

Change-Id: I5d6201e640d52ec390eb7174f8fd8c438d4efe58
Reviewed-on: https://go-review.googlesource.com/20662
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index b6d15c4..6a0947f 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -317,8 +317,8 @@
 func (s *state) Unimplementedf(msg string, args ...interface{}) {
 	s.config.Unimplementedf(s.peekLine(), msg, args...)
 }
-func (s *state) Warnl(line int, msg string, args ...interface{}) { s.config.Warnl(line, msg, args...) }
-func (s *state) Debug_checknil() bool                            { return s.config.Debug_checknil() }
+func (s *state) Warnl(line int32, msg string, args ...interface{}) { s.config.Warnl(line, msg, args...) }
+func (s *state) Debug_checknil() bool                              { return s.config.Debug_checknil() }
 
 var (
 	// dummy node for the memory variable
@@ -5229,8 +5229,8 @@
 
 // Warnl reports a "warning", which is usually flag-triggered
 // logging output for the benefit of tests.
-func (e *ssaExport) Warnl(line int, fmt_ string, args ...interface{}) {
-	Warnl(int32(line), fmt_, args...)
+func (e *ssaExport) Warnl(line int32, fmt_ string, args ...interface{}) {
+	Warnl(line, fmt_, args...)
 }
 
 func (e *ssaExport) Debug_checknil() bool {