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Diffstat (limited to 'libc/sysdeps/unix/sysv/linux/alpha/setfpucw.c')
-rw-r--r--libc/sysdeps/unix/sysv/linux/alpha/setfpucw.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/libc/sysdeps/unix/sysv/linux/alpha/setfpucw.c b/libc/sysdeps/unix/sysv/linux/alpha/setfpucw.c
new file mode 100644
index 000000000..a7e3a5581
--- /dev/null
+++ b/libc/sysdeps/unix/sysv/linux/alpha/setfpucw.c
@@ -0,0 +1,80 @@
+/* Set FP exception mask and rounding mode.
+ Copyright (C) 1996, 1997, 1998, 2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <fpu_control.h>
+#include <asm/fpu.h>
+
+extern void __ieee_set_fp_control (unsigned long);
+libc_hidden_proto(__ieee_set_fp_control)
+
+extern unsigned long __ieee_get_fp_control (void);
+libc_hidden_proto(__ieee_get_fp_control)
+
+static inline unsigned long
+rdfpcr (void)
+{
+ unsigned long fpcr;
+ asm ("excb; mf_fpcr %0" : "=f"(fpcr));
+ return fpcr;
+}
+
+
+static inline void
+wrfpcr (unsigned long fpcr)
+{
+ asm volatile ("mt_fpcr %0; excb" : : "f"(fpcr));
+}
+
+
+void
+__setfpucw (fpu_control_t fpu_control)
+{
+ unsigned long fpcr = 0, fpcw = 0;
+
+ if (!fpu_control)
+ fpu_control = _FPU_DEFAULT;
+
+ /* first, set dynamic rounding mode: */
+
+ fpcr = rdfpcr();
+ fpcr &= ~FPCR_DYN_MASK;
+ switch (fpu_control & 0xc00)
+ {
+ case _FPU_RC_NEAREST: fpcr |= FPCR_DYN_NORMAL; break;
+ case _FPU_RC_DOWN: fpcr |= FPCR_DYN_MINUS; break;
+ case _FPU_RC_UP: fpcr |= FPCR_DYN_PLUS; break;
+ case _FPU_RC_ZERO: fpcr |= FPCR_DYN_CHOPPED; break;
+ }
+ wrfpcr(fpcr);
+
+ /* now tell kernel about traps that we like to hear about: */
+
+ fpcw = __ieee_get_fp_control();
+ fpcw &= ~IEEE_TRAP_ENABLE_MASK;
+
+ if (!(fpu_control & _FPU_MASK_IM)) fpcw |= IEEE_TRAP_ENABLE_INV;
+ if (!(fpu_control & _FPU_MASK_DM)) fpcw |= IEEE_TRAP_ENABLE_UNF;
+ if (!(fpu_control & _FPU_MASK_ZM)) fpcw |= IEEE_TRAP_ENABLE_DZE;
+ if (!(fpu_control & _FPU_MASK_OM)) fpcw |= IEEE_TRAP_ENABLE_OVF;
+ if (!(fpu_control & _FPU_MASK_PM)) fpcw |= IEEE_TRAP_ENABLE_INE;
+
+ __fpu_control = fpu_control; /* update global copy */
+
+ __ieee_set_fp_control(fpcw);
+}