all: use "reports whether" consistently in the few places that didn't

Go documentation style for boolean funcs is to say:

    // Foo reports whether ...
    func Foo() bool

(rather than "returns true if")

This CL also replaces 4 uses of "iff" with the same "reports whether"
wording, which doesn't lose any meaning, and will prevent people from
sending typo fixes when they don't realize it's "if and only if". In
the past I think we've had the typo CLs updated to just say "reports
whether". So do them all at once.

(Inspired by the addition of another "returns true if" in CL 146938
in fd_plan9.go)

Created with:

$ perl -i -npe 's/returns true if/reports whether/' $(git grep -l "returns true iff" | grep -v vendor)
$ perl -i -npe 's/returns true if/reports whether/' $(git grep -l "returns true if" | grep -v vendor)

Change-Id: Ided502237f5ab0d25cb625dbab12529c361a8b9f
Reviewed-on: https://go-review.googlesource.com/c/147037
Reviewed-by: Ian Lance Taylor <iant@golang.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/runtime/panic.go b/src/runtime/panic.go
index 45be886196..5b989d28e9 100644
--- a/src/runtime/panic.go
+++ b/src/runtime/panic.go
@@ -849,7 +849,7 @@ func canpanic(gp *g) bool {
 	return true
 }
 
-// shouldPushSigpanic returns true if pc should be used as sigpanic's
+// shouldPushSigpanic reports whether pc should be used as sigpanic's
 // return PC (pushing a frame for the call). Otherwise, it should be
 // left alone so that LR is used as sigpanic's return PC, effectively
 // replacing the top-most frame with sigpanic. This is used by
@@ -887,7 +887,7 @@ func shouldPushSigpanic(gp *g, pc, lr uintptr) bool {
 	return true
 }
 
-// isAbortPC returns true if pc is the program counter at which
+// isAbortPC reports whether pc is the program counter at which
 // runtime.abort raises a signal.
 //
 // It is nosplit because it's part of the isgoexception