code review 5431047: go/printer, gofmt: more performance tweaks

go/printer, gofmt: more performance tweaks

Removed more string conversions and streamlined bottleneck
printing interface by removing unnecessary tests where possible.
About 6% faster AST printing.

Before:
- printer.BenchmarkPrint		50	32056640 ns/op

After:
- printer.BenchmarkPrint		50	30138440 ns/op (-6%)

[gri, 2011-11-23 02:02:00]

Hello r@golang.org (cc: golang-dev@googlegroups.com),

I'd like you to review this change to
https://go.googlecode.com/hg/

[r, 2011-11-23 16:20:50]

LGTM

http://codereview.appspot.com/5431047/diff/4003/src/pkg/go/printer/printer.go
File src/pkg/go/printer/printer.go (right):

http://codereview.appspot.com/5431047/diff/4003/src/pkg/go/printer/printer.go...
src/pkg/go/printer/printer.go:131: // writeNewlines writes (at most) n newlines
to p.output and updates p.pos.
drop the parens or explain why it's a parenthetical remark
writeNewlines writes up to n newlines?
it uses nlines, which i get, but the comment is confusing

http://codereview.appspot.com/5431047/diff/4003/src/pkg/go/printer/printer.go...
src/pkg/go/printer/printer.go:148: // avoids processing of the extra escape
characters and reduces runtime of
s/of the /
s/runtime/run time/

[gri, 2011-11-23 17:27:02]

http://codereview.appspot.com/5431047/diff/4003/src/pkg/go/printer/printer.go
File src/pkg/go/printer/printer.go (right):

http://codereview.appspot.com/5431047/diff/4003/src/pkg/go/printer/printer.go...
src/pkg/go/printer/printer.go:131: // writeNewlines writes (at most) n newlines
to p.output and updates p.pos.
On 2011/11/23 16:20:50, r wrote:
> drop the parens or explain why it's a parenthetical remark
> writeNewlines writes up to n newlines?
> it uses nlines, which i get, but the comment is confusing

Done.

http://codereview.appspot.com/5431047/diff/4003/src/pkg/go/printer/printer.go...
src/pkg/go/printer/printer.go:148: // avoids processing of the extra escape
characters and reduces runtime of
On 2011/11/23 16:20:50, r wrote:
> s/of the /
> s/runtime/run time/

Done.

[gri, 2011-11-23 17:27:41]

*** Submitted as http://code.google.com/p/go/source/detail?r=1b010352ab57 ***

go/printer, gofmt: more performance tweaks

Removed more string conversions and streamlined bottleneck
printing interface by removing unnecessary tests where possible.
About 6% faster AST printing.

Before:
- printer.BenchmarkPrint		50	32056640 ns/op

After:
- printer.BenchmarkPrint		50	30138440 ns/op (-6%)

R=r
CC=golang-dev
http://codereview.appspot.com/5431047