From 23fe13b4d58313c1b988a948a219661486545d54 Mon Sep 17 00:00:00 2001
From: Nikodemus Siivola <nikodemus@random-state.net>
Date: Mon, 5 Mar 2007 16:58:26 +0000
Subject: [PATCH] 1.0.3.31: fix new = and /= transformations for NaNs  * (=
 nan nan) is false, and (/= nan nan) is true, as pointed out
 by    CSR.  * More tests.

---
 src/compiler/srctran.lisp |   25 ++++++++++++++--------
 tests/float.pure.lisp     |   52 +++++++++++++++++++++++++++++++++------------
 version.lisp-expr         |    2 +-
 3 files changed, 55 insertions(+), 24 deletions(-)

diff --git a/src/compiler/srctran.lisp b/src/compiler/srctran.lisp
index 30c0c61..c49fe94 100644
--- a/src/compiler/srctran.lisp
+++ b/src/compiler/srctran.lisp
@@ -3410,14 +3410,15 @@
            (give-up-ir1-transform
             "The operands might not be the same type.")))))
 
-(labels ((maybe-float-lvar-p (lvar)
-           (neq *empty-type* (type-intersection (specifier-type 'float)
-                                                (lvar-type lvar))))
-         (maybe-invert (op inverted x y)
-           ;; Don't invert if either argument can be a float (NaNs)
-           (if (or (maybe-float-lvar-p x) (maybe-float-lvar-p y))
-               `(or (,op x y) (= x y))
-               `(if (,inverted x y) nil t))))
+(defun maybe-float-lvar-p (lvar)
+  (neq *empty-type* (type-intersection (specifier-type 'float)
+                                       (lvar-type lvar))))
+
+(flet ((maybe-invert (op inverted x y)
+         ;; Don't invert if either argument can be a float (NaNs)
+         (if (or (maybe-float-lvar-p x) (maybe-float-lvar-p y))
+             `(or (,op x y) (= x y))
+             `(if (,inverted x y) nil t))))
   (deftransform >= ((x y) (number number) *)
     "invert or open code"
     (maybe-invert '> '< x y))
@@ -3432,7 +3433,13 @@
 (macrolet ((def (name inverse reflexive-p surely-true surely-false)
              `(deftransform ,name ((x y))
                 "optimize using intervals"
-                (if (same-leaf-ref-p x y)
+                (if (and (same-leaf-ref-p x y)
+                         ;; For non-reflexive functions we don't need
+                         ;; to worry about NaNs: (non-ref-op NaN NaN) => false,
+                         ;; but with reflexive ones we don't know...
+                         ,@(when reflexive-p
+                                 '((and (not (maybe-float-lvar-p x))
+                                        (not (maybe-float-lvar-p y))))))
                     ,reflexive-p
                     (let ((ix (or (type-approximate-interval (lvar-type x))
                                   (give-up-ir1-transform)))
diff --git a/tests/float.pure.lisp b/tests/float.pure.lisp
index 5685131..1367747 100644
--- a/tests/float.pure.lisp
+++ b/tests/float.pure.lisp
@@ -162,17 +162,41 @@
     (macrolet ((test (form)
                  (let ((nform (subst '(/ 0.0 0.0) 'nan form)))
                    `(progn
-                      (assert (not (eval ',nform)))
-                      (assert (not (funcall (lambda () ,nform))))))))
-      ;; Source transforms for >= and <= used to be too eager about
-      ;; inverting the test, causing NaN issues.
-      (test (>= nan 1.0))
-      (test (>= 1.0 nan))
-      (test (>= 1.0 nan 0.0))
-      (test (>= 1.0 0.0 nan))
-      (test (>= nan 1.0 0.0))
-      (test (<= nan 1.0))
-      (test (<= 1.0 nan))
-      (test (<= 1.0 nan 2.0))
-      (test (<= 1.0 2.0 nan))
-      (test (<= nan 1.0 2.0)))))
+                      (assert (eval ',nform))
+                      (assert (eval `(let ((nan (/ 0.0 0.0)))
+                                       ,',form)))
+                      (assert (funcall
+                               (compile nil `(lambda () ,',nform))))
+                      (assert (funcall
+                               (compile nil `(lambda (nan) ,',form))
+                               (/ 0.0 0.0)))))))
+      (test (/= nan nan))
+      (test (/= nan nan nan))
+      (test (/= 1.0 nan 2.0 nan))
+      (test (/= nan 1.0 2.0 nan))
+      (test (not (= nan 1.0)))
+      (test (not (= nan nan)))
+      (test (not (= nan nan nan)))
+      (test (not (= 1.0 nan)))
+      (test (not (= nan 1.0)))
+      (test (not (= 1.0 1.0 nan)))
+      (test (not (= 1.0 nan 1.0)))
+      (test (not (= nan 1.0 1.0)))
+      (test (not (>= nan nan)))
+      (test (not (>= nan 1.0)))
+      (test (not (>= 1.0 nan)))
+      (test (not (>= 1.0 nan 0.0)))
+      (test (not (>= 1.0 0.0 nan)))
+      (test (not (>= nan 1.0 0.0)))
+      (test (not (<= nan nan)))
+      (test (not (<= nan 1.0)))
+      (test (not (<= 1.0 nan)))
+      (test (not (<= 1.0 nan 2.0)))
+      (test (not (<= 1.0 2.0 nan)))
+      (test (not (<= nan 1.0 2.0)))
+      (test (not (< nan nan)))
+      (test (not (< -1.0 nan)))
+      (test (not (< nan 1.0)))
+      (test (not (> nan nan)))
+      (test (not (> -1.0 nan)))
+      (test (not (> nan 1.0))))))
diff --git a/version.lisp-expr b/version.lisp-expr
index 6d0880f..35e3fa3 100644
--- a/version.lisp-expr
+++ b/version.lisp-expr
@@ -17,4 +17,4 @@
 ;;; checkins which aren't released. (And occasionally for internal
 ;;; versions, especially for internal versions off the main CVS
 ;;; branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
-"1.0.3.30"
+"1.0.3.31"
-- 
1.7.10.4