summaryrefslogtreecommitdiff
path: root/libm/sign.c
diff options
context:
space:
mode:
authorEric Andersen <andersen@codepoet.org>2001-11-22 14:04:29 +0000
committerEric Andersen <andersen@codepoet.org>2001-11-22 14:04:29 +0000
commit7ce331c01ce6eb7b3f5c715a38a24359da9c6ee2 (patch)
tree3a7e8476e868ae15f4da1b7ce26b2db6f434468c /libm/sign.c
parentc117dd5fb183afb1a4790a6f6110d88704be6bf8 (diff)
Totally rework the math library, this time based on the MacOs X
math library (which is itself based on the math lib from FreeBSD). -Erik
Diffstat (limited to 'libm/sign.c')
-rw-r--r--libm/sign.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/libm/sign.c b/libm/sign.c
new file mode 100644
index 000000000..524d6afe3
--- /dev/null
+++ b/libm/sign.c
@@ -0,0 +1,58 @@
+#if defined(__ppc__)
+/*******************************************************************************
+* *
+* File sign.c, *
+* Functions copysign and __signbitd. *
+* For PowerPC based machines. *
+* *
+* Copyright © 1991, 2001 Apple Computer, Inc. All rights reserved. *
+* *
+* Written by Ali Sazegari, started on June 1991. *
+* *
+* August 26 1991: no CFront Version 1.1d17 warnings. *
+* September 06 1991: passes the test suite with invalid raised on *
+* signaling nans. sane rom code behaves the same. *
+* September 24 1992: took the ̉#include support.hÓ out. *
+* Dcember 02 1992: PowerPC port. *
+* July 20 1994: __fabs added *
+* July 21 1994: deleted unnecessary functions: neg, COPYSIGNnew, *
+* and SIGNNUMnew. *
+* April 11 2001: first port to os x using gcc. *
+* removed fabs and deffered to gcc for direct *
+* instruction generation. *
+* *
+*******************************************************************************/
+
+#include "fp_private.h"
+
+/*******************************************************************************
+* *
+* Function copysign. *
+* Implementation of copysign for the PowerPC. *
+* *
+********************************************************************************
+* Note: The order of the operands in this function is reversed from that *
+* suggested in the IEEE standard 754. *
+*******************************************************************************/
+
+double copysign ( double arg2, double arg1 )
+ {
+ union
+ {
+ dHexParts hex;
+ double dbl;
+ } x, y;
+
+/*******************************************************************************
+* No need to flush NaNs out. *
+*******************************************************************************/
+
+ x.dbl = arg1;
+ y.dbl = arg2;
+
+ y.hex.high = y.hex.high & 0x7FFFFFFF;
+ y.hex.high = ( y.hex.high | ( x.hex.high & dSgnMask ) );
+
+ return y.dbl;
+ }
+#endif /* __ppc__ */