[OE-core] [PATCH] eglibc_2.13: Add support for handling sqrt & sqrtf on powerpc

Kumar Gala galak at kernel.crashing.org
Mon Aug 1 14:26:22 UTC 2011


Some of powerpc's dont support the fsqrt[s] instructions so we need an
implementation of the library functions for those processors.

Signed-off-by: Kumar Gala <galak at kernel.crashing.org>
---
 .../recipes-core/eglibc/eglibc-2.13/ppc-sqrt.patch |  538 ++++++++++++++++++++
 meta/recipes-core/eglibc/eglibc_2.13.bb            |    3 +-
 2 files changed, 540 insertions(+), 1 deletions(-)
 create mode 100644 meta/recipes-core/eglibc/eglibc-2.13/ppc-sqrt.patch

diff --git a/meta/recipes-core/eglibc/eglibc-2.13/ppc-sqrt.patch b/meta/recipes-core/eglibc/eglibc-2.13/ppc-sqrt.patch
new file mode 100644
index 0000000..203040c
--- /dev/null
+++ b/meta/recipes-core/eglibc/eglibc-2.13/ppc-sqrt.patch
@@ -0,0 +1,538 @@
+Upstream-Status: Pending
+
+2011-03-22  Joseph Myers  <joseph at codesourcery.com>
+
+        Merge from SG++ 2.11:
+
+        2010-10-05  Nathan Froyd  <froydnj at codesourcery.com>
+
+        Issue #9382
+
+        * sysdeps/powerpc/powerpc32/603e/: New directory.
+        * sysdeps/unix/sysv/linux/powerpc/powerpc32/e500mc/: New directory.
+        * sysdeps/unix/sysv/linux/powerpc/powerpc32/603e/: New directory.
+        * sysdeps/unix/sysv/linux/powerpc/powerpc32/7400/: New directory.
+        * sysdeps/powerpc/powerpc64/e5500/fpu/e_sqrtf.c: Update.
+        * sysdeps/powerpc/powerpc64/e5500/fpu/e_sqrt.c: Update.
+        * sysdeps/powerpc/powerpc64/e5500/fpu/Implies: New file.
+
+Index: libc/sysdeps/powerpc/powerpc32/603e/fpu/e_sqrt.c
+===================================================================
+--- /dev/null
++++ libc/sysdeps/powerpc/powerpc32/603e/fpu/e_sqrt.c
+@@ -0,0 +1,134 @@
++/* Double-precision floating point square root.
++   Copyright (C) 2010 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 <math.h>
++#include <math_private.h>
++#include <fenv_libc.h>
++#include <inttypes.h>
++
++#include <sysdep.h>
++#include <ldsodefs.h>
++
++static const ieee_float_shape_type a_nan = {.word = 0x7fc00000 };
++static const ieee_float_shape_type a_inf = {.word = 0x7f800000 };
++static const float two108 = 3.245185536584267269e+32;
++static const float twom54 = 5.551115123125782702e-17;
++static const float half = 0.5;
++
++/* The method is based on the descriptions in:
++
++   _The Handbook of Floating-Pointer Arithmetic_ by Muller et al., chapter 5;
++   _IA-64 and Elementary Functions: Speed and Precision_ by Markstein, chapter 9
++
++   We find the actual square root and half of its reciprocal
++   simultaneously.  */
++
++#ifdef __STDC__
++double
++__ieee754_sqrt (double b)
++#else
++double
++__ieee754_sqrt (b)
++     double b;
++#endif
++{
++  if (__builtin_expect (b > 0, 1))
++    {
++      double y, g, h, d, r;
++      ieee_double_shape_type u;
++
++      if (__builtin_expect (b != a_inf.value, 1))
++        {
++          fenv_t fe;
++
++          fe = fegetenv_register ();
++
++          u.value = b;
++
++          relax_fenv_state ();
++
++          __asm__ ("frsqrte %[estimate], %[x]\n"
++                   : [estimate] "=f" (y) : [x] "f" (b));
++
++          /* Following Muller et al, page 168, equation 5.20.
++
++             h goes to 1/(2*sqrt(b))
++             g goes to sqrt(b).
++
++             We need three iterations to get within 1ulp.  */
++
++          /* Indicate that these can be performed prior to the branch.  GCC
++             insists on sinking them below the branch, however; it seems like
++             they'd be better before the branch so that we can cover any latency
++             from storing the argument and loading its high word.  Oh well.  */
++
++          g = b * y;
++          h = 0.5 * y;
++  
++          /* Handle small numbers by scaling.  */
++          if (__builtin_expect ((u.parts.msw & 0x7ff00000) <= 0x02000000, 0))
++            return __ieee754_sqrt (b * two108) * twom54;
++
++#define FMADD(a_, c_, b_)                                               \
++          ({ double __r;                                                \
++          __asm__ ("fmadd %[r], %[a], %[c], %[b]\n"                     \
++                   : [r] "=f" (__r) : [a] "f" (a_), [c] "f" (c_), [b] "f" (b_)); \
++          __r;})
++#define FNMSUB(a_, c_, b_)                                          \
++          ({ double __r;                                                \
++          __asm__ ("fnmsub %[r], %[a], %[c], %[b]\n"                     \
++                   : [r] "=f" (__r) : [a] "f" (a_), [c] "f" (c_), [b] "f" (b_)); \
++          __r;})
++
++          r = FNMSUB (g, h, half);
++          g = FMADD (g, r, g);
++          h = FMADD (h, r, h);
++
++          r = FNMSUB (g, h, half);
++          g = FMADD (g, r, g);
++          h = FMADD (h, r, h);
++
++          r = FNMSUB (g, h, half);
++          g = FMADD (g, r, g);
++          h = FMADD (h, r, h);
++
++          /* g is now +/- 1ulp, or exactly equal to, the square root of b.  */
++
++          /* Final refinement.  */
++          d = FNMSUB (g, g, b);
++
++          fesetenv_register (fe);
++          return FMADD (d, h, g);
++        }
++    }
++  else if (b < 0)
++    {
++      /* For some reason, some PowerPC32 processors don't implement
++         FE_INVALID_SQRT.  */
++#ifdef FE_INVALID_SQRT
++      feraiseexcept (FE_INVALID_SQRT);
++
++      fenv_union_t u = { .fenv = fegetenv_register () };
++      if ((u.l[1] & FE_INVALID) == 0)
++#endif
++	feraiseexcept (FE_INVALID);
++      b = a_nan.value;
++    }
++  return f_wash (b);
++}
+Index: libc/sysdeps/powerpc/powerpc32/603e/fpu/e_sqrtf.c
+===================================================================
+--- /dev/null
++++ libc/sysdeps/powerpc/powerpc32/603e/fpu/e_sqrtf.c
+@@ -0,0 +1,101 @@
++/* Single-precision floating point square root.
++   Copyright (C) 2010 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 <math.h>
++#include <math_private.h>
++#include <fenv_libc.h>
++#include <inttypes.h>
++
++#include <sysdep.h>
++#include <ldsodefs.h>
++
++static const ieee_float_shape_type a_nan = {.word = 0x7fc00000 };
++static const ieee_float_shape_type a_inf = {.word = 0x7f800000 };
++static const float threehalf = 1.5;
++
++/* The method is based on the descriptions in:
++
++   _The Handbook of Floating-Pointer Arithmetic_ by Muller et al., chapter 5;
++   _IA-64 and Elementary Functions: Speed and Precision_ by Markstein, chapter 9
++
++   We find the reciprocal square root and use that to compute the actual
++   square root.  */
++
++#ifdef __STDC__
++float
++__ieee754_sqrtf (float b)
++#else
++float
++__ieee754_sqrtf (b)
++     float b;
++#endif
++{
++  if (__builtin_expect (b > 0, 1))
++    {
++#define FMSUB(a_, c_, b_)                                               \
++      ({ double __r;                                                    \
++        __asm__ ("fmsub %[r], %[a], %[c], %[b]\n"                       \
++                 : [r] "=f" (__r) : [a] "f" (a_), [c] "f" (c_), [b] "f" (b_)); \
++        __r;})
++#define FNMSUB(a_, c_, b_)                                              \
++      ({ double __r;                                                    \
++        __asm__ ("fnmsub %[r], %[a], %[c], %[b]\n"                      \
++                 : [r] "=f" (__r) : [a] "f" (a_), [c] "f" (c_), [b] "f" (b_)); \
++        __r;})
++
++      if (__builtin_expect (b != a_inf.value, 1))
++        {
++          double y, x;
++          fenv_t fe;
++
++          fe = fegetenv_register ();
++
++          relax_fenv_state ();
++
++          /* Compute y = 1.5 * b - b.  Uses fewer constants than y = 0.5 * b.  */
++          y = FMSUB (threehalf, b, b);
++
++          /* Initial estimate.  */
++          __asm__ ("frsqrte %[x], %[b]\n" : [x] "=f" (x) : [b] "f" (b));
++
++          /* Iterate.  x_{n+1} = x_n * (1.5 - y * (x_n * x_n)).  */
++          x = x * FNMSUB (y, x * x, threehalf);
++          x = x * FNMSUB (y, x * x, threehalf);
++          x = x * FNMSUB (y, x * x, threehalf);
++
++          /* All done.  */
++          fesetenv_register (fe);
++          return x * b;
++        }
++    }
++  else if (b < 0)
++    {
++      /* For some reason, some PowerPC32 processors don't implement
++         FE_INVALID_SQRT.  */
++#ifdef FE_INVALID_SQRT
++      feraiseexcept (FE_INVALID_SQRT);
++
++      fenv_union_t u = { .fenv = fegetenv_register () };
++      if ((u.l[1] & FE_INVALID) == 0)
++#endif
++	feraiseexcept (FE_INVALID);
++      b = a_nan.value;
++    }
++  return f_washf (b);
++}
+Index: libc/sysdeps/powerpc/powerpc64/e5500/fpu/e_sqrt.c
+===================================================================
+--- /dev/null
++++ libc/sysdeps/powerpc/powerpc64/e5500/fpu/e_sqrt.c
+@@ -0,0 +1,134 @@
++/* Double-precision floating point square root.
++   Copyright (C) 2010 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 <math.h>
++#include <math_private.h>
++#include <fenv_libc.h>
++#include <inttypes.h>
++
++#include <sysdep.h>
++#include <ldsodefs.h>
++
++static const ieee_float_shape_type a_nan = {.word = 0x7fc00000 };
++static const ieee_float_shape_type a_inf = {.word = 0x7f800000 };
++static const float two108 = 3.245185536584267269e+32;
++static const float twom54 = 5.551115123125782702e-17;
++static const float half = 0.5;
++
++/* The method is based on the descriptions in:
++
++   _The Handbook of Floating-Pointer Arithmetic_ by Muller et al., chapter 5;
++   _IA-64 and Elementary Functions: Speed and Precision_ by Markstein, chapter 9
++
++   We find the actual square root and half of its reciprocal
++   simultaneously.  */
++
++#ifdef __STDC__
++double
++__ieee754_sqrt (double b)
++#else
++double
++__ieee754_sqrt (b)
++     double b;
++#endif
++{
++  if (__builtin_expect (b > 0, 1))
++    {
++      double y, g, h, d, r;
++      ieee_double_shape_type u;
++
++      if (__builtin_expect (b != a_inf.value, 1))
++        {
++          fenv_t fe;
++
++          fe = fegetenv_register ();
++
++          u.value = b;
++
++          relax_fenv_state ();
++
++          __asm__ ("frsqrte %[estimate], %[x]\n"
++                   : [estimate] "=f" (y) : [x] "f" (b));
++
++          /* Following Muller et al, page 168, equation 5.20.
++
++             h goes to 1/(2*sqrt(b))
++             g goes to sqrt(b).
++
++             We need three iterations to get within 1ulp.  */
++
++          /* Indicate that these can be performed prior to the branch.  GCC
++             insists on sinking them below the branch, however; it seems like
++             they'd be better before the branch so that we can cover any latency
++             from storing the argument and loading its high word.  Oh well.  */
++
++          g = b * y;
++          h = 0.5 * y;
++  
++          /* Handle small numbers by scaling.  */
++          if (__builtin_expect ((u.parts.msw & 0x7ff00000) <= 0x02000000, 0))
++            return __ieee754_sqrt (b * two108) * twom54;
++
++#define FMADD(a_, c_, b_)                                               \
++          ({ double __r;                                                \
++          __asm__ ("fmadd %[r], %[a], %[c], %[b]\n"                     \
++                   : [r] "=f" (__r) : [a] "f" (a_), [c] "f" (c_), [b] "f" (b_)); \
++          __r;})
++#define FNMSUB(a_, c_, b_)                                          \
++          ({ double __r;                                                \
++          __asm__ ("fnmsub %[r], %[a], %[c], %[b]\n"                     \
++                   : [r] "=f" (__r) : [a] "f" (a_), [c] "f" (c_), [b] "f" (b_)); \
++          __r;})
++
++          r = FNMSUB (g, h, half);
++          g = FMADD (g, r, g);
++          h = FMADD (h, r, h);
++
++          r = FNMSUB (g, h, half);
++          g = FMADD (g, r, g);
++          h = FMADD (h, r, h);
++
++          r = FNMSUB (g, h, half);
++          g = FMADD (g, r, g);
++          h = FMADD (h, r, h);
++
++          /* g is now +/- 1ulp, or exactly equal to, the square root of b.  */
++
++          /* Final refinement.  */
++          d = FNMSUB (g, g, b);
++
++          fesetenv_register (fe);
++          return FMADD (d, h, g);
++        }
++    }
++  else if (b < 0)
++    {
++      /* For some reason, some PowerPC32 processors don't implement
++         FE_INVALID_SQRT.  */
++#ifdef FE_INVALID_SQRT
++      feraiseexcept (FE_INVALID_SQRT);
++
++      fenv_union_t u = { .fenv = fegetenv_register () };
++      if ((u.l[1] & FE_INVALID) == 0)
++#endif
++	feraiseexcept (FE_INVALID);
++      b = a_nan.value;
++    }
++  return f_wash (b);
++}
+Index: libc/sysdeps/powerpc/powerpc64/e5500/fpu/e_sqrtf.c
+===================================================================
+--- /dev/null
++++ libc/sysdeps/powerpc/powerpc64/e5500/fpu/e_sqrtf.c
+@@ -0,0 +1,101 @@
++/* Single-precision floating point square root.
++   Copyright (C) 2010 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 <math.h>
++#include <math_private.h>
++#include <fenv_libc.h>
++#include <inttypes.h>
++
++#include <sysdep.h>
++#include <ldsodefs.h>
++
++static const ieee_float_shape_type a_nan = {.word = 0x7fc00000 };
++static const ieee_float_shape_type a_inf = {.word = 0x7f800000 };
++static const float threehalf = 1.5;
++
++/* The method is based on the descriptions in:
++
++   _The Handbook of Floating-Pointer Arithmetic_ by Muller et al., chapter 5;
++   _IA-64 and Elementary Functions: Speed and Precision_ by Markstein, chapter 9
++
++   We find the reciprocal square root and use that to compute the actual
++   square root.  */
++
++#ifdef __STDC__
++float
++__ieee754_sqrtf (float b)
++#else
++float
++__ieee754_sqrtf (b)
++     float b;
++#endif
++{
++  if (__builtin_expect (b > 0, 1))
++    {
++#define FMSUB(a_, c_, b_)                                               \
++      ({ double __r;                                                    \
++        __asm__ ("fmsub %[r], %[a], %[c], %[b]\n"                       \
++                 : [r] "=f" (__r) : [a] "f" (a_), [c] "f" (c_), [b] "f" (b_)); \
++        __r;})
++#define FNMSUB(a_, c_, b_)                                              \
++      ({ double __r;                                                    \
++        __asm__ ("fnmsub %[r], %[a], %[c], %[b]\n"                      \
++                 : [r] "=f" (__r) : [a] "f" (a_), [c] "f" (c_), [b] "f" (b_)); \
++        __r;})
++
++      if (__builtin_expect (b != a_inf.value, 1))
++        {
++          double y, x;
++          fenv_t fe;
++
++          fe = fegetenv_register ();
++
++          relax_fenv_state ();
++
++          /* Compute y = 1.5 * b - b.  Uses fewer constants than y = 0.5 * b.  */
++          y = FMSUB (threehalf, b, b);
++
++          /* Initial estimate.  */
++          __asm__ ("frsqrte %[x], %[b]\n" : [x] "=f" (x) : [b] "f" (b));
++
++          /* Iterate.  x_{n+1} = x_n * (1.5 - y * (x_n * x_n)).  */
++          x = x * FNMSUB (y, x * x, threehalf);
++          x = x * FNMSUB (y, x * x, threehalf);
++          x = x * FNMSUB (y, x * x, threehalf);
++
++          /* All done.  */
++          fesetenv_register (fe);
++          return x * b;
++        }
++    }
++  else if (b < 0)
++    {
++      /* For some reason, some PowerPC32 processors don't implement
++         FE_INVALID_SQRT.  */
++#ifdef FE_INVALID_SQRT
++      feraiseexcept (FE_INVALID_SQRT);
++
++      fenv_union_t u = { .fenv = fegetenv_register () };
++      if ((u.l[1] & FE_INVALID) == 0)
++#endif
++	feraiseexcept (FE_INVALID);
++      b = a_nan.value;
++    }
++  return f_washf (b);
++}
+Index: libc/sysdeps/unix/sysv/linux/powerpc/powerpc32/603e/fpu/Implies
+===================================================================
+--- /dev/null
++++ libc/sysdeps/unix/sysv/linux/powerpc/powerpc32/603e/fpu/Implies
+@@ -0,0 +1 @@
++powerpc/powerpc32/603e/fpu
+Index: libc/sysdeps/unix/sysv/linux/powerpc/powerpc32/7400/fpu/Implies
+===================================================================
+--- /dev/null
++++ libc/sysdeps/unix/sysv/linux/powerpc/powerpc32/7400/fpu/Implies
+@@ -0,0 +1 @@
++powerpc/powerpc32/603e/fpu
+Index: libc/sysdeps/unix/sysv/linux/powerpc/powerpc32/e500mc/fpu/Implies
+===================================================================
+--- /dev/null
++++ libc/sysdeps/unix/sysv/linux/powerpc/powerpc32/e500mc/fpu/Implies
+@@ -0,0 +1 @@
++powerpc/powerpc32/603e/fpu
+Index: libc/sysdeps/unix/sysv/linux/powerpc/powerpc64/e5500/fpu/Implies
+===================================================================
+--- /dev/null
++++ libc/sysdeps/unix/sysv/linux/powerpc/powerpc64/e5500/fpu/Implies
+@@ -0,0 +1 @@
++powerpc/powerpc64/e5500/fpu
+Index: libc/sysdeps/unix/sysv/linux/powerpc/powerpc32/e5500/fpu/Implies
+===================================================================
+--- /dev/null
++++ libc/sysdeps/unix/sysv/linux/powerpc/powerpc32/e5500/fpu/Implies
+@@ -0,0 +1 @@
++powerpc/powerpc32/603e/fpu
diff --git a/meta/recipes-core/eglibc/eglibc_2.13.bb b/meta/recipes-core/eglibc/eglibc_2.13.bb
index 41fe7c7..772c01f 100644
--- a/meta/recipes-core/eglibc/eglibc_2.13.bb
+++ b/meta/recipes-core/eglibc/eglibc_2.13.bb
@@ -3,7 +3,7 @@ require eglibc.inc
 SRCREV = "14157"
 
 DEPENDS += "gperf-native"
-PR = "r9"
+PR = "r10"
 PR_append = "+svnr${SRCPV}"
 
 EGLIBC_BRANCH="eglibc-2_13"
@@ -16,6 +16,7 @@ SRC_URI = "svn://www.eglibc.org/svn/branches/;module=${EGLIBC_BRANCH};proto=http
            file://etc/ld.so.conf \
            file://generate-supported.mk \
            file://glibc_bug_fix_12454.patch \
+           file://ppc-sqrt.patch \
 	   "
 LIC_FILES_CHKSUM = "file://LICENSES;md5=98a1128c4b58120182cbea3b1752d8b9 \
       file://COPYING;md5=393a5ca445f6965873eca0259a17f833 \
-- 
1.7.3.4





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