* rtl-c.scm (estate-make-for-rtl-c): Delete args context, owner,
rtl-cover-fns?, macro?. All callers updated.
(estate-make-for-normal-rtl-c): Delete, have all callers call
estate-make-for-rtl-c directly.
(rtl-c-parsed): Pass #:outer-expr to estate-make-for-rtl-c.
(rtl-c, rtl-c-expr-parsed, rtl-c-expr, rtl-c++-parsed, rtl-c++): Ditto.
* rtl-c.scm (/par-replace-set-dest-expr-fn): New function,
replaces /par-replace-set-dests.
(/par-replace-set-src-expr-fn): New function, replaces
/par-replace-set-srcs.
(s-parallel): Rewrite.
* rtl.scm (rtx-pretty-strdump): New function.
* rtl-traverse.scm (/rtx-canon-error): Use it.
(<eval-state>): New member outer-expr.
(estate-error): Include outer expression in error message if present.