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-rw-r--r--sysdeps/powerpc/fpu/fegetround.c4
-rw-r--r--sysdeps/powerpc/fpu/fenv_libc.h37
-rw-r--r--sysdeps/powerpc/fpu/fesetround.c18
-rw-r--r--sysdeps/powerpc/fpu/math_ldbl.h189
4 files changed, 230 insertions, 18 deletions
diff --git a/sysdeps/powerpc/fpu/fegetround.c b/sysdeps/powerpc/fpu/fegetround.c
index ae521fdf10..93663ad546 100644
--- a/sysdeps/powerpc/fpu/fegetround.c
+++ b/sysdeps/powerpc/fpu/fegetround.c
@@ -23,7 +23,5 @@
 int
 fegetround (void)
 {
-  int result;
-  asm ("mcrfs 7,7 ; mfcr %0" : "=r"(result) : : "cr7"); \
-  return result & 3;
+  return __fegetround();
 }
diff --git a/sysdeps/powerpc/fpu/fenv_libc.h b/sysdeps/powerpc/fpu/fenv_libc.h
index 7ae12a7d2b..fd5fc0c767 100644
--- a/sysdeps/powerpc/fpu/fenv_libc.h
+++ b/sysdeps/powerpc/fpu/fenv_libc.h
@@ -1,5 +1,5 @@
 /* Internal libc stuff for floating point environment routines.
-   Copyright (C) 1997 Free Software Foundation, Inc.
+   Copyright (C) 1997, 2006 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
@@ -54,6 +54,41 @@ typedef union
   unsigned int l[2];
 } fenv_union_t;
 
+
+static inline int
+__fegetround (void)
+{
+  int result;
+  asm volatile ("mcrfs 7,7\n\t"
+		"mfcr  %0" : "=r"(result) : : "cr7");
+  return result & 3;
+}
+#define fegetround() __fegetround()
+
+static inline int
+__fesetround (int round)
+{
+  if ((unsigned int) round < 2)
+    {
+       asm volatile ("mtfsb0 30");
+       if ((unsigned int) round == 0)
+         asm volatile ("mtfsb0 31");
+       else
+         asm volatile ("mtfsb1 31");
+    }
+  else
+    {
+       asm volatile ("mtfsb1 30");
+       if ((unsigned int) round == 2)
+         asm volatile ("mtfsb0 31");
+       else
+         asm volatile ("mtfsb1 31");
+    }
+
+  return 0;
+}
+#define fesetround(mode) __fesetround(mode)
+
 /* Definitions of all the FPSCR bit numbers */
 enum {
   FPSCR_FX = 0,    /* exception summary */
diff --git a/sysdeps/powerpc/fpu/fesetround.c b/sysdeps/powerpc/fpu/fesetround.c
index 67518d0df4..a7efa3bbb0 100644
--- a/sysdeps/powerpc/fpu/fesetround.c
+++ b/sysdeps/powerpc/fpu/fesetround.c
@@ -1,5 +1,5 @@
 /* Set current rounding direction.
-   Copyright (C) 1997, 2005 Free Software Foundation, Inc.
+   Copyright (C) 1997, 2005, 2006 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
 
@@ -20,23 +20,13 @@
 
 #include <fenv_libc.h>
 
+#undef fesetround
 int
 fesetround (int round)
 {
-  fenv_union_t u;
-
   if ((unsigned int) round > 3)
     return 1;
-
-  /* Get the current state.  */
-  u.fenv = fegetenv_register ();
-
-  /* Set the relevant bits.  */
-  u.l[1] = (u.l[1] & ~3)  |  (round & 3);
-
-  /* Put the new state in effect.  */
-  fesetenv_register (u.fenv);
-
-  return 0;
+  else
+    return __fesetround(round);
 }
 libm_hidden_def (fesetround)
diff --git a/sysdeps/powerpc/fpu/math_ldbl.h b/sysdeps/powerpc/fpu/math_ldbl.h
new file mode 100644
index 0000000000..6cd6d0bdfe
--- /dev/null
+++ b/sysdeps/powerpc/fpu/math_ldbl.h
@@ -0,0 +1,189 @@
+#ifndef _MATH_PRIVATE_H_
+#error "Never use <math_ldbl.h> directly; include <math_private.h> instead."
+#endif
+
+#include <sysdeps/ieee754/ldbl-128/math_ldbl.h>
+#include <ieee754.h>
+  
+static inline void
+ldbl_extract_mantissa (int64_t *hi64, u_int64_t *lo64, int *exp, long double x)
+{
+  /* We have 105 bits of mantissa plus one implicit digit.  Since
+     106 bits are representable we use the first implicit digit for
+     the number before the decimal point and the second implicit bit
+     as bit 53 of the mantissa.  */
+  unsigned long long hi, lo;
+  int ediff;
+  union ibm_extended_long_double eldbl;
+  eldbl.d = x;
+  *exp = eldbl.ieee.exponent - IBM_EXTENDED_LONG_DOUBLE_BIAS;
+
+  lo = ((long long)eldbl.ieee.mantissa2 << 32) | eldbl.ieee.mantissa3;
+  hi = ((long long)eldbl.ieee.mantissa0 << 32) | eldbl.ieee.mantissa1;
+  /* If the lower double is not a denomal or zero then set the hidden
+     53rd bit.  */
+  if (eldbl.ieee.exponent2 > 0x001)
+    {
+      lo |= (1ULL << 52);
+      lo = lo << 7; /* pre-shift lo to match ieee854.  */
+      /* The lower double is normalized separately from the upper.  We
+	 may need to adjust the lower manitissa to reflect this.  */
+      ediff = eldbl.ieee.exponent - eldbl.ieee.exponent2;
+      if (ediff > 53)
+	lo = lo >> (ediff-53);
+    }
+  hi |= (1ULL << 52);
+  
+  if ((eldbl.ieee.negative != eldbl.ieee.negative2)
+      && ((eldbl.ieee.exponent2 != 0) && (lo != 0LL)))
+    {
+      hi--;
+      lo = (1ULL << 60) - lo;
+      if (hi < (1ULL << 52))
+	{
+	  /* we have a borrow from the hidden bit, so shift left 1.  */
+	  hi = (hi << 1) | (lo >> 59);
+	  lo = 0xfffffffffffffffLL & (lo << 1);
+	  *exp = *exp - 1;
+	}
+    }
+  *lo64 = (hi << 60) | lo;
+  *hi64 = hi >> 4;
+}
+
+static inline long double
+ldbl_insert_mantissa (int sign, int exp, int64_t hi64, u_int64_t lo64)
+{
+  union ibm_extended_long_double u;
+  unsigned long hidden2, lzcount;
+  unsigned long long hi, lo;
+
+  u.ieee.negative = sign;
+  u.ieee.negative2 = sign;
+  u.ieee.exponent = exp + IBM_EXTENDED_LONG_DOUBLE_BIAS;
+  u.ieee.exponent2 = exp-53 + IBM_EXTENDED_LONG_DOUBLE_BIAS;
+  /* Expect 113 bits (112 bits + hidden) right justified in two longs.
+     The low order 53 bits (52 + hidden) go into the lower double */ 
+  lo = (lo64 >> 7)& ((1ULL << 53) - 1);
+  hidden2 = (lo64 >> 59) &  1ULL;
+  /* The high order 53 bits (52 + hidden) go into the upper double */
+  hi = (lo64 >> 60) & ((1ULL << 11) - 1);
+  hi |= (hi64 << 4);
+
+  if (lo != 0LL)
+    {
+      /* hidden2 bit of low double controls rounding of the high double.
+	 If hidden2 is '1' then round up hi and adjust lo (2nd mantissa)
+	 plus change the sign of the low double to compensate.  */
+      if (hidden2)
+	{
+	  hi++;
+	  u.ieee.negative2 = !sign;
+	  lo = (1ULL << 53) - lo;
+	}
+      /* The hidden bit of the lo mantissa is zero so we need to
+	 normalize the it for the low double.  Shift it left until the
+	 hidden bit is '1' then adjust the 2nd exponent accordingly.  */ 
+
+      if (sizeof (lo) == sizeof (long))
+	lzcount = __builtin_clzl (lo);
+      else if ((lo >> 32) != 0)
+	lzcount = __builtin_clzl ((long) (lo >> 32));
+      else
+	lzcount = __builtin_clzl ((long) lo) + 32;
+      lzcount = lzcount - 11;
+      if (lzcount > 0)
+	{
+	  int expnt2 = u.ieee.exponent2 - lzcount;
+	  if (expnt2 >= 1)
+	    {
+	      /* Not denormal.  Normalize and set low exponent.  */
+	      lo = lo << lzcount;
+	      u.ieee.exponent2 = expnt2;
+	    }
+	  else
+	    {
+	      /* Is denormal.  */
+	      lo = lo << (lzcount + expnt2);
+	      u.ieee.exponent2 = 0;
+	    }
+	}
+    }
+  else
+    {
+      u.ieee.negative2 = 0;
+      u.ieee.exponent2 = 0;
+    }
+
+  u.ieee.mantissa3 = lo & ((1ULL << 32) - 1);
+  u.ieee.mantissa2 = (lo >> 32) & ((1ULL << 20) - 1);
+  u.ieee.mantissa1 = hi & ((1ULL << 32) - 1);
+  u.ieee.mantissa0 = (hi >> 32) & ((1ULL << 20) - 1);
+  return u.d;
+}
+  
+/* gcc generates disgusting code to pack and unpack long doubles.
+   This tells gcc that pack/unpack is really a nop.  We use fr1/fr2
+   because those are the regs used to pass/return a single
+   long double arg.  */
+static inline long double
+ldbl_pack (double a, double aa)
+{
+  register long double x __asm__ ("fr1");
+  register double xh __asm__ ("fr1");
+  register double xl __asm__ ("fr2");
+  xh = a;
+  xl = aa;
+  __asm__ ("" : "=f" (x) : "f" (xh), "f" (xl));
+  return x;
+}
+
+static inline void
+ldbl_unpack (long double l, double *a, double *aa)
+{
+  register long double x __asm__ ("fr1");
+  register double xh __asm__ ("fr1");
+  register double xl __asm__ ("fr2");
+  x = l;
+  __asm__ ("" : "=f" (xh), "=f" (xl) : "f" (x));
+  *a = xh;
+  *aa = xl;
+}
+
+
+/* Convert a finite long double to canonical form.
+   Does not handle +/-Inf properly.  */
+static inline void
+ldbl_canonicalize (double *a, double *aa)
+{
+  double xh, xl;
+
+  xh = *a + *aa;
+  xl = (*a - xh) + *aa;
+  *a = xh;
+  *aa = xl;
+}
+
+/* Simple inline nearbyint (double) function .
+   Only works in the default rounding mode
+   but is useful in long double rounding functions.  */
+static inline double
+ldbl_nearbyint (double a)
+{
+  double two52 = 0x10000000000000LL;
+
+  if (__builtin_expect ((__builtin_fabs (a) < two52), 1))
+    {
+      if (__builtin_expect ((a > 0.0), 1))
+	{
+	  a += two52;
+	  a -= two52;
+	}
+      else if (__builtin_expect ((a < 0.0), 1))
+	{
+	  a = two52 - a;
+	  a = -(a - two52);
+	}
+    }
+  return a;
+}