Sun Jan 24 20:34:30 2016 UTC ()
Fix incorrect magic numbers in scaling.  From FreeBSD commit 23397, by
way of Rin Okuyama.  Fixes PR lib/50698.


(gson)
diff -r1.9 -r1.10 src/lib/libm/src/e_hypotf.c
cvs diff -r1.9 -r1.10 src/lib/libm/src/e_hypotf.c (expand / switch to unified diff)

--- src/lib/libm/src/e_hypotf.c 2008/04/25 22:21:53 1.9
+++ src/lib/libm/src/e_hypotf.c 2016/01/24 20:34:30 1.10
@@ -5,27 +5,27 @@ @@ -5,27 +5,27 @@
5/* 5/*
6 * ==================================================== 6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 * 8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business. 9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this 10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice 11 * software is freely granted, provided that this notice
12 * is preserved. 12 * is preserved.
13 * ==================================================== 13 * ====================================================
14 */ 14 */
15 15
16#include <sys/cdefs.h> 16#include <sys/cdefs.h>
17#if defined(LIBM_SCCS) && !defined(lint) 17#if defined(LIBM_SCCS) && !defined(lint)
18__RCSID("$NetBSD: e_hypotf.c,v 1.9 2008/04/25 22:21:53 christos Exp $"); 18__RCSID("$NetBSD: e_hypotf.c,v 1.10 2016/01/24 20:34:30 gson Exp $");
19#endif 19#endif
20 20
21#include "math.h" 21#include "math.h"
22#include "math_private.h" 22#include "math_private.h"
23 23
24float 24float
25__ieee754_hypotf(float x, float y) 25__ieee754_hypotf(float x, float y)
26{ 26{
27 float a=x,b=y,t1,t2,yy1,y2,w; 27 float a=x,b=y,t1,t2,yy1,y2,w;
28 int32_t j,k,ha,hb; 28 int32_t j,k,ha,hb;
29 29
30 GET_FLOAT_WORD(ha,x); 30 GET_FLOAT_WORD(ha,x);
31 ha &= 0x7fffffff; 31 ha &= 0x7fffffff;
@@ -33,42 +33,42 @@ __ieee754_hypotf(float x, float y) @@ -33,42 +33,42 @@ __ieee754_hypotf(float x, float y)
33 hb &= 0x7fffffff; 33 hb &= 0x7fffffff;
34 if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;} 34 if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;}
35 SET_FLOAT_WORD(a,ha); /* a <- |a| */ 35 SET_FLOAT_WORD(a,ha); /* a <- |a| */
36 SET_FLOAT_WORD(b,hb); /* b <- |b| */ 36 SET_FLOAT_WORD(b,hb); /* b <- |b| */
37 if((ha-hb)>0xf000000) {return a+b;} /* x/y > 2**30 */ 37 if((ha-hb)>0xf000000) {return a+b;} /* x/y > 2**30 */
38 k=0; 38 k=0;
39 if(ha > 0x58800000) { /* a>2**50 */ 39 if(ha > 0x58800000) { /* a>2**50 */
40 if(ha >= 0x7f800000) { /* Inf or NaN */ 40 if(ha >= 0x7f800000) { /* Inf or NaN */
41 w = a+b; /* for sNaN */ 41 w = a+b; /* for sNaN */
42 if(ha == 0x7f800000) w = a; 42 if(ha == 0x7f800000) w = a;
43 if(hb == 0x7f800000) w = b; 43 if(hb == 0x7f800000) w = b;
44 return w; 44 return w;
45 } 45 }
46 /* scale a and b by 2**-60 */ 46 /* scale a and b by 2**-68 */
47 ha -= 0x5d800000; hb -= 0x5d800000; k += 60; 47 ha -= 0x22000000; hb -= 0x22000000; k += 68;
48 SET_FLOAT_WORD(a,ha); 48 SET_FLOAT_WORD(a,ha);
49 SET_FLOAT_WORD(b,hb); 49 SET_FLOAT_WORD(b,hb);
50 } 50 }
51 if(hb < 0x26800000) { /* b < 2**-50 */ 51 if(hb < 0x26800000) { /* b < 2**-50 */
52 if(hb <= 0x007fffff) { /* subnormal b or 0 */ 52 if(hb <= 0x007fffff) { /* subnormal b or 0 */
53 if(hb==0) return a; 53 if(hb==0) return a;
54 SET_FLOAT_WORD(t1,0x3f000000); /* t1=2^126 */ 54 SET_FLOAT_WORD(t1,0x7e800000); /* t1=2^126 */
55 b *= t1; 55 b *= t1;
56 a *= t1; 56 a *= t1;
57 k -= 126; 57 k -= 126;
58 } else { /* scale a and b by 2^60 */ 58 } else { /* scale a and b by 2^68 */
59 ha += 0x5d800000; /* a *= 2^60 */ 59 ha += 0x22000000; /* a *= 2^68 */
60 hb += 0x5d800000; /* b *= 2^60 */ 60 hb += 0x22000000; /* b *= 2^68 */
61 k -= 60; 61 k -= 68;
62 SET_FLOAT_WORD(a,ha); 62 SET_FLOAT_WORD(a,ha);
63 SET_FLOAT_WORD(b,hb); 63 SET_FLOAT_WORD(b,hb);
64 } 64 }
65 } 65 }
66 /* medium size a and b */ 66 /* medium size a and b */
67 w = a-b; 67 w = a-b;
68 if (w>b) { 68 if (w>b) {
69 SET_FLOAT_WORD(t1,ha&0xfffff000); 69 SET_FLOAT_WORD(t1,ha&0xfffff000);
70 t2 = a-t1; 70 t2 = a-t1;
71 w = __ieee754_sqrtf(t1*t1-(b*(-b)-t2*(a+t1))); 71 w = __ieee754_sqrtf(t1*t1-(b*(-b)-t2*(a+t1)));
72 } else { 72 } else {
73 a = a+a; 73 a = a+a;
74 SET_FLOAT_WORD(yy1,hb&0xfffff000); 74 SET_FLOAT_WORD(yy1,hb&0xfffff000);