go/test/syntax
Robert Griesemer b569b87ca1 cmd/compile/internal/gc: recursive-descent parser
This is a translation of the yacc-based parser with adjustements
to make the grammar work for a recursive-descent parser followed
by cleanups and simplifications.

The yacc actions were mostly literally copied for correctness
with better temporary names.

A few of the syntax tests were adjusted for slightly different
error messages (it is very difficult to match the yacc-based
error messages in all cases, and sometimes the new parser could
produce better errors).

The new parser is enabled by default.
To switch back to the yacc-based parser, set -oldparser.
To hardwire the switch back, uncomment "oldparser = 1" in lex.go.

- passes all.bash
- ~18% reduced parse time per file on average for make.bash
- ~3% reduced compile time for building cmd/compile

Change-Id: Icb5651bb9d8b9f66261762d2c94a03793050d4ce
Reviewed-on: https://go-review.googlesource.com/16665
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-13 14:53:57 +00:00
..
chan.go
chan1.go
composite.go
else.go
forvar.go
if.go
import.go
interface.go
semi1.go
semi2.go
semi3.go
semi4.go
semi5.go
semi6.go
semi7.go
topexpr.go
typesw.go
vareq.go
vareq1.go