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
walkstate -> walkstmt
walktype -> walkexpr; stmts moved to walkstmt
walktype and friends have a final Node **init
argument that can have side effects appended,
making it more explicit when they do and do not happen.
this replaces the old global addtop and addtotop.
delete switch map and interface conversion cases
(dropped from the language months ago).
R=ken
OCL=31465
CL=31468
do not bother warning about marks left
on stack after syntax errors.
leave OCONV nodes in tree to avoid type errors
arising from multiple walks.
R=ken
OCL=30639
CL=30662
structtype{a:1, a:2}
maptypetype{"xx":1, "xx":2}
arraytypetype{5:1, 5:2}
2. bug in registerization concerning
alias of a struct and one of its elements
3. code optimization of struct.field
(which exposed bug in 2)
R=r
OCL=29315
CL=29315
