add expand-omit-library-invocations

original commit: 35dbfdaa9ea3832f2ded108b7edcaead61922007

LOG

@@ -774,6 +774,6 @@
     5_3.ss, 5_3.ms, fl.ms, root-experr*, patch*
 - fix bug in date->time-utc caused by incorrect use of difftime in Windows
     stats.c, date.ms, release_notes.stex
-- add current-generate-id, which can be useful for avoiding library
-  recompilation
+- add current-generate-id and expand-omit-library-invocations, which can be
+  useful for avoiding library recompilation and redundant invocation checks
     syntax.ss, record.ss, primdata.ss, misc.ms, system.stex

csug/system.stex

@@ -2228,6 +2228,27 @@ Configure \scheme{make-x-generator} this way only in situations where
 the potential for unspecified failure is more tolerable than
 recompilation.
 
+%----------------------------------------------------------------------------
+\entryheader
+\formdef{expand-omit-library-invocations}{\categorythreadparameter}{expand-omit-library-invocations}
+\listlibraries
+\endentryheader
+
+\noindent
+This boolean-valued parameter determines whether library uses are
+recorded in macro expansion. Normally, when an expression expands to a
+reference to a library-defined identifier, the expansion is prefixed
+with a check to ensure that the exporting library is defined and
+invoked. If \scheme{expand-omit-library-invocations} is set to true,
+the prefix is omitted.
+
+Setting \scheme{expand-omit-library-invocations} to true makes sense
+only when evaluating many small expressions in a context where all
+referenced libraries are known to be present and already invoked, and
+only when it's worth saving the small overhead of representing and
+running the check.
+
+
 \section{Source Directories and Files\label{SECTSYSTEMSOURCE}}
 
 %----------------------------------------------------------------------------

mats/misc.ms

@@ -5041,3 +5041,24 @@
                (def))))
     (equal? 3 (return-x)))
 )
+
+(mat expand-omit-library-invocations
+  (not (expand-omit-library-invocations))
+  (begin
+    (library (define-m-as-one) (export m) (import (chezscheme)) (define m 1))
+    (define (find-define-m-as-one s)
+      (or (eq? s 'define-m-as-one)
+          (and (pair? s)
+                (or (find-define-m-as-one (car s))
+                        (find-define-m-as-one (cdr s))))))
+    #t)
+  (find-define-m-as-one (expand '(let () (import (define-m-as-one)) m)))
+  (begin
+    (expand-omit-library-invocations 'yes)
+    (eq? #t (expand-omit-library-invocations)))
+  (not (find-define-m-as-one (expand '(let () (import (define-m-as-one)) m))))
+  (begin
+    (expand-omit-library-invocations #f)
+    (not (expand-omit-library-invocations)))
+  (find-define-m-as-one (expand '(let () (import (define-m-as-one)) m)))
+  )

s/primdata.ss

@@ -947,6 +947,7 @@
   (enable-cross-library-optimization [sig [() -> (boolean)] [(ptr) -> (void)]] [flags unrestricted])
   (enable-object-counts [sig [() -> (boolean)] [(ptr) -> (void)]] [flags])
   (eval-syntax-expanders-when [sig [() -> (list)] [(sub-list) -> (void)]] [flags])
+  (expand-omit-library-invocations [sig [() -> (boolean)] [(ptr) -> (void)]] [flags])
   (expand-output [sig [() -> (maybe-textual-output-port)] [(maybe-textual-output-port) -> (void)]] [flags])
   (expand/optimize-output [sig [() -> (maybe-textual-output-port)] [(maybe-textual-output-port) -> (void)]] [flags])
   (exit-handler [sig [() -> (procedure)] [(procedure) -> (void)]] [flags])

s/syntax.ss

@@ -3420,7 +3420,12 @@
 
 (define residualize-invoke-requirements
   (case-lambda
-    [(code) (residualize-invoke-requirements '() (require-visit) (require-invoke) code)]
+    [(code) (residualize-invoke-requirements '()
+                                             (require-visit)
+                                             (if (expand-omit-library-invocations)
+                                                 '()
+                                                 (require-invoke))
+                                             code)]
     [(import* visit* invoke* code)
      (build-sequence no-source
        `(,@(map (build-requirement '$import-library) import*)
@@ -4961,6 +4966,10 @@
     (lambda ()
       (list-loaded-libraries)))
 
+  (set! expand-omit-library-invocations
+    ($make-thread-parameter #f
+      (lambda (v) (and v #t))))
+
   (let ()
     (define maybe-get-lib
       (lambda (who libref)