Hi Ludovic,
> commit 2446f8e126d9a7c145c4868f2a918d2dfb226d4e
> Author: Ludovic Courtès <l...@gnu.org>
> Date: Sat Oct 6 01:24:46 2012 +0200
>
> Simplify calls to `equal?' when one argument is a constant.
>
> * module/language/tree-il/primitives.scm (*primitive-expand-table*): Add
> expansion rules for `equal?', when called with one constant and
> another argument.
>
> * test-suite/tests/tree-il.test (pass-if-primitives-resolved): New
> macro.
> ("primitives"): New test prefix.
This commit has some problems.
> diff --git a/module/language/tree-il/primitives.scm
> b/module/language/tree-il/primitives.scm
> index a1c5adc..dc0a145 100644
> --- a/module/language/tree-il/primitives.scm
> +++ b/module/language/tree-il/primitives.scm
> @@ -491,6 +491,33 @@
> (bytevector-ieee-double-native-set! vec (* i 8) x))
>
> (hashq-set! *primitive-expand-table*
> + 'equal?
> + (case-lambda
> + ((src a b)
> + ;; Simplify cases where either A or B is constant.
> + (define (maybe-simplify a b)
> + (and (const? a)
> + (let ((v (const-exp a)))
> + (cond
> + ((eq? #f v)
> + (make-application src (make-primitive-ref #f 'not)
> + (list b)))
(not v) is not the same as (equal? #f v) when v is #nil.
> + ((eq? '() v)
> + (make-application src (make-primitive-ref #f
> 'null?)
> + (list b)))
(null? v) is not the same as (equal? '() v) when v is #nil.
> + ((or (eq? #t v)
> + (eq? #nil v)
> + (symbol? v)
> + (and (integer? v)
> + (<= v most-positive-fixnum)
> + (>= v most-negative-fixnum)))
> + (make-application src (make-primitive-ref #f 'eq?)
> + (list a b)))
42.0 is an integer in the fixnum range, but (eq? 42.0 v) is not the same
as (equal? 42.0 v).
I have pushed fixes for these.
Also, is there any particular reason you didn't apply the same
optimizations to 'eqv?'?
Mark
