From: Taylor R Campbell <campbell@mumble.net>
Date: Sat, 27 Oct 2018 01:39:58 +0000 (+0000)
Subject: Define and export some more floating-point parameters.
X-Git-Tag: mit-scheme-pucked-10.1.2~16^2~148
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=3dc80642c54b5c8f3893ede0e3fa430d2f97bae3;p=mit-scheme.git

Define and export some more floating-point parameters.
---

diff --git a/src/runtime/arith.scm b/src/runtime/arith.scm
index 71c66b399..990af61f5 100644
--- a/src/runtime/arith.scm
+++ b/src/runtime/arith.scm
@@ -93,6 +93,17 @@ USA.
 (define rec:pi/2 (flo:* 2. (flo:atan2 1. 1.)))
 (define rec:pi (flo:* 2. rec:pi/2))
 
+(define flo:epsilon)
+(define flo:log-epsilon)
+(define flo:normal-exponent-max-base-2)
+(define flo:normal-exponent-min-base-2)
+(define flo:normal-exponent-max-base-e)
+(define flo:normal-exponent-min-base-e)
+(define flo:normal-exponent-max-base-10)
+(define flo:normal-exponent-min-base-10)
+(define flo:subnormal-exponent-min-base-2)
+(define flo:subnormal-exponent-min-base-e)
+(define flo:subnormal-exponent-min-base-10)
 (define flo:significand-digits-base-2)
 (define flo:significand-digits-base-10)
 (define int:flonum-integer-limit)
@@ -111,6 +122,29 @@ USA.
 		  (flo:/ (int:->flonum p)
 			 (flo:/ (flo:log 10.) (flo:log 2.))))))
     (set! int:flonum-integer-limit (int:expt 2 p)))
+  (set! flo:epsilon microcode-id/floating-epsilon)
+  (set! flo:log-epsilon (flo:log flo:epsilon))
+  (set! flo:normal-exponent-max-base-2 microcode-id/floating-exponent-max)
+  (set! flo:normal-exponent-min-base-2 microcode-id/floating-exponent-min)
+  (set! flo:subnormal-exponent-min-base-2
+	(int:- flo:normal-exponent-min-base-2
+	       (int:- flo:significand-digits-base-2 1)))
+  (set! flo:normal-exponent-max-base-e
+	(flo:log (flo:expt 2. (int:->flonum flo:normal-exponent-max-base-2))))
+  (set! flo:normal-exponent-min-base-e
+	(flo:log (flo:expt 2. (int:->flonum flo:normal-exponent-min-base-2))))
+  (set! flo:subnormal-exponent-min-base-e
+	(flo:+
+	 flo:normal-exponent-min-base-e
+	 (flo:log
+	  (flo:expt 2.
+		    (flo:- 0. (int:->flonum flo:significand-digits-base-2))))))
+  (set! flo:normal-exponent-max-base-10
+	(flo:/ flo:normal-exponent-max-base-e (flo:log 10.)))
+  (set! flo:normal-exponent-min-base-10
+	(flo:/ flo:normal-exponent-min-base-e (flo:log 10.)))
+  (set! flo:subnormal-exponent-min-base-10
+	(flo:/ flo:subnormal-exponent-min-base-e (flo:log 10.)))
   unspecific)
 
 (define (initialize-package!)
diff --git a/src/runtime/runtime.pkg b/src/runtime/runtime.pkg
index 685c0b8a6..3a05dd288 100644
--- a/src/runtime/runtime.pkg
+++ b/src/runtime/runtime.pkg
@@ -3354,8 +3354,19 @@ USA.
 	  cube
 	  exact-nonnegative-integer?
 	  exact-positive-integer?
+	  flo:epsilon
+	  flo:log-epsilon
+	  flo:normal-exponent-max-base-10
+	  flo:normal-exponent-max-base-2
+	  flo:normal-exponent-max-base-e
+	  flo:normal-exponent-min-base-10
+	  flo:normal-exponent-min-base-2
+	  flo:normal-exponent-min-base-e
 	  flo:significand-digits-base-10
 	  flo:significand-digits-base-2
+	  flo:subnormal-exponent-min-base-10
+	  flo:subnormal-exponent-min-base-2
+	  flo:subnormal-exponent-min-base-e
 	  flonum-printer:engineering-output
 	  flonum-printer:normal-output
 	  flonum-printer:scientific-output