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authorRichard Henderson <rth@redhat.com>2000-03-20 20:32:11 +0000
committerRichard Henderson <rth@redhat.com>2000-03-20 20:32:11 +0000
commitb7434f8243547189c14e42559c09c14c41d521ad (patch)
tree06c7bbb887a1c7db4b0140260a53e39eb3fb0aec /sysdeps/alpha/fpu/s_ceil.c
parent45159f0082e995c3a0e4829dd7c8662ffc0bd041 (diff)
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* sysdeps/alpha/fpu/fraiseexcpt.c: Use get/set_fp_control instead of arithmetic instructions.
        * sysdeps/alpha/fpu/s_ceil.c: Use round to -inf instead of playing
        with the fpcr.  Protect from INV exception.
        * sysdeps/alpha/fpu/s_ceilf.c: Likewise.
        * sysdeps/alpha/fpu/s_floor.c: Protect from INV exception.
        * sysdeps/alpha/fpu/s_floorf.c: Likewise.

        * sysdeps/alpha/fpu/s_copysign.c: New.
        * sysdeps/alpha/fpu/s_copysignf.c: New.
        * sysdeps/alpha/fpu/s_fabs.c: New.
        * sysdeps/alpha/fpu/s_fabsf.c: New.
        * sysdeps/alpha/fpu/s_rint.c: New.
        * sysdeps/alpha/fpu/s_rintf.c: New.
	* sysdeps/alpha/fpu/fraiseexcpt.c: Use get/set_fp_control instead
	of arithmetic instructions.

	* sysdeps/alpha/fpu/s_ceil.c: Use round to -inf instead of playing
	with the fpcr.  Protect from INV exception.
	* sysdeps/alpha/fpu/s_ceilf.c: Likewise.
	* sysdeps/alpha/fpu/s_floor.c: Protect from INV exception.
	* sysdeps/alpha/fpu/s_floorf.c: Likewise.

	* sysdeps/alpha/fpu/s_copysign.c: New.
	* sysdeps/alpha/fpu/s_copysignf.c: New.
	* sysdeps/alpha/fpu/s_fabs.c: New.
	* sysdeps/alpha/fpu/s_fabsf.c: New.
	* sysdeps/alpha/fpu/s_rint.c: New.
	* sysdeps/alpha/fpu/s_rintf.c: New.
Diffstat (limited to 'sysdeps/alpha/fpu/s_ceil.c')
-rw-r--r--sysdeps/alpha/fpu/s_ceil.c36
1 files changed, 16 insertions, 20 deletions
diff --git a/sysdeps/alpha/fpu/s_ceil.c b/sysdeps/alpha/fpu/s_ceil.c
index 23491db5ac..f30db008ce 100644
--- a/sysdeps/alpha/fpu/s_ceil.c
+++ b/sysdeps/alpha/fpu/s_ceil.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1998 Free Software Foundation, Inc.
+/* Copyright (C) 1998, 2000 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Richard Henderson.
 
@@ -19,34 +19,30 @@
 
 #include <math.h>
 
+/* Use the -inf rounding mode conversion instructions to implement
+   ceil, via something akin to -floor(-x).  This is much faster than
+   playing with the fpcr to achieve +inf rounding mode.  */
+
 double
 __ceil (double x)
 {
-  if (x != 0 && fabs (x) < 9007199254740992.0)  /* 1 << DBL_MANT_DIG */
+  if (isless (fabs (x), 9007199254740992.0))	/* 1 << DBL_MANT_DIG */
     {
-      double tmp1;
-      unsigned long fpcr0, fpcr1;
-      unsigned long pinf = 3UL << 58;
-
-      /* Set round to +inf.  */
-      __asm __volatile("excb; mf_fpcr %0" : "=f"(fpcr0));
-      __asm __volatile("mt_fpcr %0; excb" : : "f"(fpcr0 | pinf));
+      double tmp1, new_x;
 
-      /* Calculate!  */
+      new_x = -x;
+      __asm (
 #ifdef _IEEE_FP_INEXACT
-      __asm("cvttq/svid %2,%1\n\tcvtqt/suid %1,%0"
-	    : "=f"(x), "=&f"(tmp1)
-	    : "f"(x));
+	     "cvttq/svim %2,%1\n\t"
 #else
-      __asm("cvttq/svd %2,%1\n\tcvtqt/d %1,%0"
-	    : "=f"(x), "=&f"(tmp1)
-	    : "f"(x));
+	     "cvttq/svm %2,%1\n\t"
 #endif
+	     "cvtqt/m %1,%0\n\t"
+	     : "=f"(new_x), "=&f"(tmp1)
+	     : "f"(new_x));
 
-      /* Reset rounding mode, while retaining new exception bits.  */
-      __asm __volatile("excb; mf_fpcr %0" : "=f"(fpcr1));
-      fpcr0 = (fpcr0 & pinf) | (fpcr1 & ~pinf);
-      __asm __volatile("mt_fpcr %0; excb" : : "f"(fpcr0));
+      /* Fix up the negation we did above, as well as handling -0 properly. */
+      x = copysign(new_x, x);
     }
   return x;
 }