diff options
Diffstat (limited to 'sysdeps/alpha/fpu/s_ceilf.c')
| -rw-r--r-- | sysdeps/alpha/fpu/s_ceilf.c | 44 |
1 files changed, 20 insertions, 24 deletions
diff --git a/sysdeps/alpha/fpu/s_ceilf.c b/sysdeps/alpha/fpu/s_ceilf.c index 3defaeb01e..35c51a2766 100644 --- a/sysdeps/alpha/fpu/s_ceilf.c +++ b/sysdeps/alpha/fpu/s_ceilf.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. @@ -19,39 +19,35 @@ #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. */ + float __ceilf (float x) { - if (x != 0 && fabsf (x) < 16777216.0f) /* 1 << FLT_MANT_DIG */ + if (isless (fabsf (x), 16777216.0f)) /* 1 << FLT_MANT_DIG */ { - float tmp1, tmp2; - 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)); + /* Note that Alpha S_Floating is stored in registers in a + restricted T_Floating format, so we don't even need to + convert back to S_Floating in the end. The initial + conversion to T_Floating is needed to handle denormals. */ - /* Calculate! - Note that Alpha S_Floating is stored in registers in a - restricted T_Floating format, so we don't even need to - convert back to S_Floating in the end. The initial - conversion to T_Floating is needed to handle denormals. */ + float tmp1, tmp2, new_x; + new_x = -x; + __asm ("cvtst/s %3,%2\n\t" #ifdef _IEEE_FP_INEXACT - __asm("cvtst/s %3,%2\n\tcvttq/svid %2,%1\n\tcvtqt/suid %1,%0" - : "=f"(x), "=&f"(tmp1), "=&f"(tmp2) - : "f"(x)); + "cvttq/svim %2,%1\n\t" #else - __asm("cvtst/s %3,%2\n\tcvttq/svd %2,%1\n\tcvtqt/d %1,%0" - : "=f"(x), "=&f"(tmp1), "=&f"(tmp2) - : "f"(x)); + "cvttq/svm %2,%1\n\t" #endif + "cvtqt/m %1,%0\n\t" + : "=f"(new_x), "=&f"(tmp1), "=&f"(tmp2) + : "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 = copysignf(new_x, x); } return x; } |