From a79f202573194dc7e3bb4bf3d72253362e3e7053 Mon Sep 17 00:00:00 2001
From: Taylor R Campbell <campbell@mumble.net>
Date: Sun, 10 Feb 2019 22:35:19 +0000
Subject: [PATCH] Convert multi-LETREC to internal definitions in arith.scm.
---
src/runtime/arith.scm | 43 +++++++++++++++++++------------------------
1 file changed, 19 insertions(+), 24 deletions(-)
diff --git a/src/runtime/arith.scm b/src/runtime/arith.scm
index 7307bb759..345d1b93e 100644
--- a/src/runtime/arith.scm
+++ b/src/runtime/arith.scm
@@ -921,30 +921,25 @@ USA.
(let ((k (int:- (integer-length-in-bits n)
(integer-length-in-bits d)))
(p flo:significand-digits-base-2))
- (letrec
- ((step1
- (lambda (n d)
- ;; (assert (< (expt 2 (- k 1)) (/ n d) (expt 2 (+ k 1))))
- (if (int:negative? k)
- (step2 (integer-shift-left n (int:negate k)) d)
- (step2 n (integer-shift-left d k)))))
- (step2
- (lambda (n d)
- ;; (assert (< 1/2 (/ n d) 2))
- (if (int:< n d)
- (step3 n d (int:- k p))
- (step3 n (int:* 2 d) (int:- (int:1+ k) p)))))
- (step3
- (lambda (n d e)
- ;; (assert (and (<= 1/2 (/ n d)) (< (/ n d) 1)))
- (let ((n (int:round (integer-shift-left n p) d)))
- (if (int:= n int:flonum-integer-limit)
- (step4 (int:quotient n 2) (int:1+ e))
- (step4 n e)))))
- (step4
- (lambda (n e)
- (flo:denormalize (integer->flonum n #b11) e))))
- (step1 n d))))
+ (define (step1 n d)
+ ;; (assert (< (expt 2 (- k 1)) (/ n d) (expt 2 (+ k 1))))
+ (if (int:negative? k)
+ (step2 (integer-shift-left n (int:negate k)) d)
+ (step2 n (integer-shift-left d k))))
+ (define (step2 n d)
+ ;; (assert (< 1/2 (/ n d) 2))
+ (if (int:< n d)
+ (step3 n d (int:- k p))
+ (step3 n (int:* 2 d) (int:- (int:1+ k) p))))
+ (define (step3 n d e)
+ ;; (assert (and (<= 1/2 (/ n d)) (< (/ n d) 1)))
+ (let ((n (int:round (integer-shift-left n p) d)))
+ (if (int:= n int:flonum-integer-limit)
+ (step4 (int:quotient n 2) (int:1+ e))
+ (step4 n e))))
+ (define (step4 n e)
+ (flo:denormalize (integer->flonum n #b11) e))
+ (step1 n d)))
(define (slow-method n d)
(if (int:positive? n)
--
2.25.1