PowerPC: Fix nearbyint/nearbyintf result for FE_DOWNWARD

This patch fixes the powerpc32 optimized nearbyint/nearbyintf bogus
results for FE_DOWNWARD rounding mode.  This is due wrong instructions
sequence used in the rounding calculation (two subtractions instead of
adition and a subtraction).

Fixes BZ#16815.

diff --git a/ChangeLog b/ChangeLog
index a0bb465..faaea3c 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2014-04-06  Adhemerval Zanella  <azanella@linux.vnet.ibm.com>
+
+       [BZ #16815]
+       * sysdeps/powerpc/powerpc32/fpu/s_nearbyint.S (__nearbyint): Fix
+       result for FE_DOWNWARD rounding mode.
+       * sysdeps/powerpc/powerpc32/fpu/s_nearbyintf.S (__nearbyintf):
+       Likewise.
+       * sysdeps/powerpc/fpu/libm-test-ulps: Update.
+
 2014-04-04  Chris Metcalf  <cmetcalf@tilera.com>
 
        * sysdeps/tile/dl-runtime.c (_dl_unmap): Fix cut-and-paste bug

diff --git a/NEWS b/NEWS
index c7114da..db8cc10 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -14,7 +14,7 @@ Version 2.20
   16611, 16613, 16623, 16632, 16634, 16639, 16642, 16648, 16649, 16670,
   16674, 16677, 16680, 16683, 16689, 16695, 16701, 16706, 16707, 16712,
   16713, 16714, 16731, 16739, 16743, 16758, 16759, 16760, 16770, 16786,
-  16789, 16799, 16800.
+  16789, 16799, 16800, 16815.
 
 * Running the testsuite no longer terminates as soon as a test fails.
   Instead, a file tests.sum (xtests.sum from "make xcheck") is generated,

diff --git a/sysdeps/powerpc/fpu/libm-test-ulps b/sysdeps/powerpc/fpu/libm-test-ulps
index 27f228c..3319233 100644 (file)
--- a/sysdeps/powerpc/fpu/libm-test-ulps
+++ b/sysdeps/powerpc/fpu/libm-test-ulps
@@ -452,6 +452,54 @@ ifloat: 1
 ildouble: 1
 ldouble: 1
 
+Function: Real part of "catan_downward":
+double: 1
+float: 1
+idouble: 1
+ifloat: 1
+ildouble: 5
+ldouble: 5
+
+Function: Imaginary part of "catan_downward":
+double: 2
+float: 2
+idouble: 2
+ifloat: 2
+ildouble: 6
+ldouble: 6
+
+Function: Real part of "catan_towardzero":
+double: 1
+float: 1
+idouble: 1
+ifloat: 1
+ildouble: 6
+ldouble: 6
+
+Function: Imaginary part of "catan_towardzero":
+double: 2
+float: 1
+idouble: 2
+ifloat: 1
+ildouble: 2
+ldouble: 2
+
+Function: Real part of "catan_upward":
+double: 1
+float: 1
+idouble: 1
+ifloat: 1
+ildouble: 3
+ldouble: 3
+
+Function: Imaginary part of "catan_upward":
+double: 3
+float: 3
+idouble: 3
+ifloat: 3
+ildouble: 5
+ldouble: 5
+
 Function: Real part of "catanh":
 double: 4
 float: 1
@@ -466,6 +514,54 @@ ifloat: 1
 ildouble: 1
 ldouble: 1
 
+Function: Real part of "catanh_downward":
+double: 2
+float: 2
+idouble: 2
+ifloat: 2
+ildouble: 3
+ldouble: 3
+
+Function: Imaginary part of "catanh_downward":
+double: 1
+float: 2
+idouble: 1
+ifloat: 2
+ildouble: 5
+ldouble: 5
+
+Function: Real part of "catanh_towardzero":
+double: 2
+float: 1
+idouble: 2
+ifloat: 1
+ildouble: 2
+ldouble: 2
+
+Function: Imaginary part of "catanh_towardzero":
+double: 1
+float: 2
+idouble: 1
+ifloat: 2
+ildouble: 6
+ldouble: 6
+
+Function: Real part of "catanh_upward":
+double: 4
+float: 3
+idouble: 4
+ifloat: 3
+ildouble: 8
+ldouble: 8
+
+Function: Imaginary part of "catanh_upward":
+double: 1
+float: 1
+idouble: 1
+ifloat: 1
+ildouble: 3
+ldouble: 3
+
 Function: "cbrt":
 double: 1
 float: 1
@@ -672,6 +768,102 @@ ifloat: 1
 ildouble: 2
 ldouble: 2
 
+Function: Real part of "clog10_downward":
+double: 3
+float: 3
+idouble: 3
+ifloat: 3
+ildouble: 7
+ldouble: 7
+
+Function: Imaginary part of "clog10_downward":
+double: 3
+float: 2
+idouble: 3
+ifloat: 2
+ildouble: 7
+ldouble: 7
+
+Function: Real part of "clog10_towardzero":
+double: 3
+float: 2
+idouble: 3
+ifloat: 2
+ildouble: 8
+ldouble: 8
+
+Function: Imaginary part of "clog10_towardzero":
+double: 3
+float: 2
+idouble: 3
+ifloat: 2
+ildouble: 7
+ldouble: 7
+
+Function: Real part of "clog10_upward":
+double: 4
+float: 3
+idouble: 4
+ifloat: 3
+ildouble: 8
+ldouble: 8
+
+Function: Imaginary part of "clog10_upward":
+double: 2
+float: 2
+idouble: 2
+ifloat: 2
+ildouble: 6
+ldouble: 6
+
+Function: Real part of "clog_downward":
+double: 2
+float: 2
+idouble: 2
+ifloat: 2
+ildouble: 3
+ldouble: 3
+
+Function: Imaginary part of "clog_downward":
+double: 1
+float: 2
+idouble: 1
+ifloat: 2
+ildouble: 3
+ldouble: 3
+
+Function: Real part of "clog_towardzero":
+double: 2
+float: 2
+idouble: 2
+ifloat: 2
+ildouble: 3
+ldouble: 3
+
+Function: Imaginary part of "clog_towardzero":
+double: 1
+float: 2
+idouble: 1
+ifloat: 2
+ildouble: 4
+ldouble: 4
+
+Function: Real part of "clog_upward":
+double: 2
+float: 1
+idouble: 2
+ifloat: 1
+ildouble: 6
+ldouble: 6
+
+Function: Imaginary part of "clog_upward":
+double: 2
+float: 1
+idouble: 2
+ifloat: 1
+ildouble: 3
+ldouble: 3
+
 Function: "cos":
 double: 2
 float: 1

diff --git a/sysdeps/powerpc/powerpc32/fpu/s_nearbyint.S b/sysdeps/powerpc/powerpc32/fpu/s_nearbyint.S
index 2734738..05ab40e 100644 (file)
--- a/sysdeps/powerpc/powerpc32/fpu/s_nearbyint.S
+++ b/sysdeps/powerpc/powerpc32/fpu/s_nearbyint.S
@@ -53,17 +53,17 @@ ENTRY (__nearbyint)
        fcmpu   cr7,fp1,fp12    /* if (x > 0.0 */
        ble     cr7,L(lessthanzero)
        mtfsb0  4*cr7+lt        /* Disable FE_INEXACT exception */
-       fadd    fp0,fp1,fp13    /* x += TWO52 */
-       fsub    fp1,fp0,fp13    /* x -= TWO52 */
+       fadd    fp1,fp1,fp13    /* x += TWO52 */
+       fsub    fp1,fp1,fp13    /* x -= TWO52 */
        fabs    fp1,fp1         /* if (x == 0.0 */
        mtfsb0  4*cr1+eq        /* Clear any FE_INEXACT exception */
        blr
 L(lessthanzero):
        bgelr   cr7
        mtfsb0  4*cr7+lt        /* Disable FE_INEXACT exception */
-       fsub    fp0,fp13,fp1    /* x -= TWO52 */
-       fsub    fp0,fp0,fp13    /* x += TWO52 */
-       fneg    fp1,fp0         /* if (x == 0.0) */
+       fsub    fp1,fp1,fp13    /* x -= TWO52 */
+       fadd    fp1,fp1,fp13    /* x += TWO52 */
+       fnabs   fp1,fp1         /* if (x == 0.0) */
        mtfsb0  4*cr1+eq        /* Clear any FE_INEXACT exception */
        blr
 END (__nearbyint)

diff --git a/sysdeps/powerpc/powerpc32/fpu/s_nearbyintf.S b/sysdeps/powerpc/powerpc32/fpu/s_nearbyintf.S
index 11bdc77..7449a5f 100644 (file)
--- a/sysdeps/powerpc/powerpc32/fpu/s_nearbyintf.S
+++ b/sysdeps/powerpc/powerpc32/fpu/s_nearbyintf.S
@@ -52,16 +52,17 @@ ENTRY (__nearbyintf)
        fcmpu   cr7,fp1,fp12            /* if (x > 0.0 */
        ble     cr7,L(lessthanzero)
        mtfsb0  4*cr7+lt                /* Disable FE_INEXACT exception */
-       fadds   fp0,fp1,fp13            /* x += TWO23 */
-       fsubs   fp1,fp0,fp13            /* x -= TWO23 */
+       fadds   fp1,fp1,fp13            /* x += TWO23 */
+       fsubs   fp1,fp1,fp13            /* x -= TWO23 */
+       fabs    fp1,fp1                 /* if (x == 0.0) */
        mtfsb0  4*cr1+eq                /* Clear any FE_INEXACT exception */
        blr
 L(lessthanzero):
        bgelr   cr7
        mtfsb0  4*cr7+lt                /* Disable FE_INEXACT exception */
-       fsubs   fp0,fp13,fp1            /* x -= TWO23 */
-       fsubs   fp0,fp0,fp13            /* x += TWO23 */
-       fneg    fp1,fp0                 /* if (x == 0.0) */
+       fsubs   fp1,fp1,fp13            /* x -= TWO23 */
+       fadds   fp1,fp1,fp13            /* x += TWO23 */
+       fnabs   fp1,fp1                 /* if (x == 0.0) */
        mtfsb0  4*cr1+eq                /* Clear any FE_INEXACT exception */
        blr
 END (__nearbyintf)