5g/6g/8g: add import statements to export metadata, mapping package path to package name.
recognize "" as the path of the package in export metadata.
use "" as the path of the package in object symbol names.
5c/6c/8c, 5a/6a/8a: rewrite leading . to "". so that ·Sin means Sin in this package.
5l/6l/8l: rewrite "" in symbol names as object files are read.
gotest: handle new symbol names.
gopack: handle new import lines in export metadata.
Collectively, these changes eliminate the assumption of a global
name space in the object file formats. Higher level pieces such as
reflect and the computation of type hashes still depend on the
assumption; we're not done yet.
R=ken2, r, ken3
CC=golang-dev
https://golang.org/cl/186263
archive size +70%
binary size +30%
old
wreck.mtv=; ls -l /Users/rsc/bin/{godoc,gofmt}
-rwxr-xr-x 1 rsc eng 1487922 Aug 13 13:21 /Users/rsc/bin/godoc
-rwxr-xr-x 1 rsc eng 995995 Aug 13 13:21 /Users/rsc/bin/gofmt
wreck.mtv=; du -sh $GOROOT/pkg/
9.5M /home/rsc/go/pkg/
wreck.mtv=;
new
wreck.mtv=; ls -l /Users/rsc/bin/{godoc,gofmt}
-rwxr-xr-x 1 rsc eng 2014390 Aug 13 14:25 /Users/rsc/bin/godoc
-rwxr-xr-x 1 rsc eng 1268705 Aug 13 14:25 /Users/rsc/bin/gofmt
wreck.mtv=; du -sh $GOROOT/pkg
16M /home/rsc/go/pkg
wreck.mtv=;
R=ken
OCL=33217
CL=33220
introduce NodeList* type in compiler to replace OLIST.
this clarifies where lists can and cannot occur.
list append and concatenation are now cheap.
the _r rules are gone from yacc.
rev and unrev are gone.
no more lists of lists.
the representation of assignments is a bit clunkier.
split into OAS (1=1) and OAS2 (2 or more on one side).
delete dead chanrecv3 code.
delay construction of func types.
R=ken
OCL=31745
CL=31762
