From: Roland McGrath Date: Tue, 13 Feb 1996 11:40:36 +0000 (+0000) Subject: New file from Schwab X-Git-Tag: upstream/2.30~29664 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=13987e686c9e72b4ccad2a786e9cac84739b3488;p=external%2Fglibc.git New file from Schwab * sysdeps/unix/sysv/linux/m68k/fpu_control.h: New file. --- diff --git a/ChangeLog b/ChangeLog index 00f9a75..225c188 100644 --- a/ChangeLog +++ b/ChangeLog @@ -31,6 +31,8 @@ Sat Feb 10 13:09:03 1996 Andreas Schwab reserved (read as 0, ignored on write) + * 15 -> enable trap for BSUN exception + * 14 -> enable trap for SNAN exception + * 13 -> enable trap for OPERR exception + * 12 -> enable trap for OVFL exception + * 11 -> enable trap for UNFL exception + * 10 -> enable trap for DZ exception + * 9 -> enable trap for INEX2 exception + * 8 -> enable trap for INEX1 exception + * 7-6 -> Precision Control + * 5-4 -> Rounding Control + * 3-0 -> zero (read as 0, write as 0) + * + * + * Precision Control: + * 00 - round to extended precision + * 01 - round to single precision + * 10 - round to double precision + * 11 - undefined + * + * Rounding Control: + * 00 - rounding to nearest (RN) + * 01 - rounding toward zero (RZ) + * 10 - rounding (down)toward minus infinity (RM) + * 11 - rounding (up) toward plus infinity (RP) + * + * The hardware default is 0x0000. I choose 0x5400. + */ + +#include + +/* masking of interrupts */ +#define _FPU_MASK_BSUN 0x8000 +#define _FPU_MASK_SNAN 0x4000 +#define _FPU_MASK_OPERR 0x2000 +#define _FPU_MASK_OVFL 0x1000 +#define _FPU_MASK_UNFL 0x0800 +#define _FPU_MASK_DZ 0x0400 +#define _FPU_MASK_INEX1 0x0200 +#define _FPU_MASK_INEX2 0x0100 + +/* precision control */ +#define _FPU_EXTENDED 0x00 /* RECOMMENDED */ +#define _FPU_DOUBLE 0x80 +#define _FPU_SINGLE 0x40 /* DO NOT USE */ + +/* rounding control */ +#define _FPU_RC_NEAREST 0x00 /* RECOMMENDED */ +#define _FPU_RC_ZERO 0x10 +#define _FPU_RC_DOWN 0x20 +#define _FPU_RC_UP 0x30 + +#define _FPU_RESERVED 0xFFFF000F /* Reserved bits in fpucr */ + + +/* Now two recommended fpucr */ + +/* Linux default: + - extended precision + - rounding to nearest + - exceptions on overflow, zero divide and NaN */ +#define _FPU_DEFAULT 0x00005400 + +/* IEEE: same as above, but exceptions. We must make it non-zero so + that __setfpucw works. This bit will be ignored. */ +#define _FPU_IEEE 0x00000001 + +/* Type of the control word. */ +typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__))); + +/* Macros for accessing the hardware control word. */ +#define _FPU_GETCW(cw) __asm__ ("fmove%.l %!, %0" : "=dm" (cw)) +#define _FPU_SETCW(cw) __asm__ ("fmove%.l %0, %!" : "dm" (cw)) + +/* Default control word set at startup. */ +extern fpu_control_t __fpu_control; + +__BEGIN_DECLS + +/* Called at startup. It can be used to manipulate fpu control register. */ +extern void __setfpucw __P ((fpu_control_t)); + +__END_DECLS + +#endif /* _M68K_FPU_CONTROL_H */