From c00f26c0eaba5a9680aac0f98de4b6e385a8cb82 Mon Sep 17 00:00:00 2001
From: Adhemerval Zanella <azanella@linux.vnet.ibm.com>
Date: Fri, 8 Mar 2013 11:07:15 -0300
Subject: [PATCH 18/42] PowerPC: unify math_ldbl.h implementations

This patch removes redudant definition from PowerPC specific
math_ldbl, using the definitions from ieee754 math_ldbl.h.
(backported from commit edf66e57fc2bac083ecc9756a5fe47f9041ed3bb)
---
 sysdeps/ieee754/ldbl-128ibm/math_ldbl.h |   10 +
 sysdeps/powerpc/Implies                 |    1 
 sysdeps/powerpc/fpu/math_ldbl.h         |  171 +-------------------------------
 sysdeps/unix/sysv/linux/powerpc/Implies |    4 
 4 files changed, 18 insertions(+), 168 deletions(-)
 delete mode 100644 sysdeps/unix/sysv/linux/powerpc/Implies

--- a/sysdeps/ieee754/ldbl-128ibm/math_ldbl.h
+++ b/sysdeps/ieee754/ldbl-128ibm/math_ldbl.h
@@ -125,7 +125,7 @@
 /* Handy utility functions to pack/unpack/cononicalize and find the nearbyint
    of long double implemented as double double.  */
 static inline long double
-ldbl_pack (double a, double aa)
+default_ldbl_pack (double a, double aa)
 {
   union ibm_extended_long_double u;
   u.dd[0] = a;
@@ -134,7 +134,7 @@
 }
 
 static inline void
-ldbl_unpack (long double l, double *a, double *aa)
+default_ldbl_unpack (long double l, double *a, double *aa)
 {
   union ibm_extended_long_double u;
   u.d = l;
@@ -142,6 +142,12 @@
   *aa = u.dd[1];
 }
 
+#ifndef ldbl_pack
+# define ldbl_pack   default_ldbl_pack
+#endif
+#ifndef ldbl_unpack
+# define ldbl_unpack default_ldbl_unpack
+#endif
 
 /* Convert a finite long double to canonical form.
    Does not handle +/-Inf properly.  */
--- a/sysdeps/powerpc/Implies
+++ b/sysdeps/powerpc/Implies
@@ -1,4 +1,5 @@
 # On PowerPC we use the IBM extended long double format.
 ieee754/ldbl-128ibm
+ieee754/ldbl-opt
 ieee754/dbl-64
 ieee754/flt-32
--- a/sysdeps/powerpc/fpu/math_ldbl.h
+++ b/sysdeps/powerpc/fpu/math_ldbl.h
@@ -2,132 +2,12 @@
 #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.  */
+/* GCC does not optimize the default ldbl_pack code to not spill register
+   in the stack. The following optimization 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)
+ldbl_pack_ppc (double a, double aa)
 {
   register long double x __asm__ ("fr1");
   register double xh __asm__ ("fr1");
@@ -139,7 +19,7 @@
 }
 
 static inline void
-ldbl_unpack (long double l, double *a, double *aa)
+ldbl_unpack_ppc (long double l, double *a, double *aa)
 {
   register long double x __asm__ ("fr1");
   register double xh __asm__ ("fr1");
@@ -150,40 +30,7 @@
   *aa = xl;
 }
 
+#define ldbl_pack   ldbl_pack_ppc
+#define ldbl_unpack ldbl_unpack_ppc
 
-/* 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;
-}
+#include <sysdeps/ieee754/ldbl-128ibm/math_ldbl.h>
--- a/sysdeps/unix/sysv/linux/powerpc/Implies
+++ /dev/null
@@ -1,4 +0,0 @@
-# Make sure these routines come before ldbl-opt.
-ieee754/ldbl-128ibm
-# These supply the ABI compatibility for when long double was double.
-ieee754/ldbl-opt
