From 4896f049205013528f1f0df7f7cbb52e8c5664d1 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 1 Aug 2014 12:13:50 -1000 Subject: Force eval for fma implementations --- ChangeLog | 9 +++++++++ sysdeps/ieee754/dbl-64/s_fma.c | 11 ++++++----- sysdeps/ieee754/ldbl-128/s_fmal.c | 11 ++++++----- sysdeps/ieee754/ldbl-96/s_fma.c | 11 ++++++----- sysdeps/ieee754/ldbl-96/s_fmal.c | 11 ++++++----- 5 files changed, 33 insertions(+), 20 deletions(-) diff --git a/ChangeLog b/ChangeLog index 5aaea43891..c3006f57e7 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,12 @@ +2014-08-01 Richard Henderon + + * sysdeps/ieee754/dbl-64/s_fma.c (__fma): Use math_force_eval before + feclearexcept; use math_opt_barrier instead of open-coded asm; fix + typo in exact zero test. + * sysdeps/ieee754/ldbl-128/s_fmal.c (__fmal): Likewise. + * sysdeps/ieee754/ldbl-96/s_fma.c (__fma): Likewise. + * sysdeps/ieee754/ldbl-96/s_fmal.c (__fmal): Likewise. + 2014-08-01 Roland McGrath * sysdeps/unix/sysv/linux/arm/sysdep.h (PTR_MANGLE_LOAD, PTR_MANGLE) diff --git a/sysdeps/ieee754/dbl-64/s_fma.c b/sysdeps/ieee754/dbl-64/s_fma.c index 389acd4cde..77065aaba1 100644 --- a/sysdeps/ieee754/dbl-64/s_fma.c +++ b/sysdeps/ieee754/dbl-64/s_fma.c @@ -198,16 +198,17 @@ __fma (double x, double y, double z) t1 = m1 - t1; t2 = z - t2; double a2 = t1 + t2; + /* Ensure the arithmetic is not scheduled after feclearexcept call. */ + math_force_eval (m2); + math_force_eval (a2); feclearexcept (FE_INEXACT); - /* If the result is an exact zero, ensure it has the correct - sign. */ + /* If the result is an exact zero, ensure it has the correct sign. */ if (a1 == 0 && m2 == 0) { libc_feupdateenv (&env); - /* Ensure that round-to-nearest value of z + m1 is not - reused. */ - asm volatile ("" : "=m" (z) : "m" (z)); + /* Ensure that round-to-nearest value of z + m1 is not reused. */ + z = math_opt_barrier (z); return z + m1; } diff --git a/sysdeps/ieee754/ldbl-128/s_fmal.c b/sysdeps/ieee754/ldbl-128/s_fmal.c index 1d5f27b7b6..814709482b 100644 --- a/sysdeps/ieee754/ldbl-128/s_fmal.c +++ b/sysdeps/ieee754/ldbl-128/s_fmal.c @@ -203,16 +203,17 @@ __fmal (long double x, long double y, long double z) t1 = m1 - t1; t2 = z - t2; long double a2 = t1 + t2; + /* Ensure the arithmetic is not scheduled after feclearexcept call. */ + math_force_eval (m2); + math_force_eval (a2); feclearexcept (FE_INEXACT); - /* If the result is an exact zero, ensure it has the correct - sign. */ + /* If the result is an exact zero, ensure it has the correct sign. */ if (a1 == 0 && m2 == 0) { feupdateenv (&env); - /* Ensure that round-to-nearest value of z + m1 is not - reused. */ - asm volatile ("" : "=m" (z) : "m" (z)); + /* Ensure that round-to-nearest value of z + m1 is not reused. */ + z = math_opt_barrier (z); return z + m1; } diff --git a/sysdeps/ieee754/ldbl-96/s_fma.c b/sysdeps/ieee754/ldbl-96/s_fma.c index 354be4eae9..a27102eff1 100644 --- a/sysdeps/ieee754/ldbl-96/s_fma.c +++ b/sysdeps/ieee754/ldbl-96/s_fma.c @@ -64,16 +64,17 @@ __fma (double x, double y, double z) t1 = m1 - t1; t2 = z - t2; long double a2 = t1 + t2; + /* Ensure the arithmetic is not scheduled after feclearexcept call. */ + math_force_eval (m2); + math_force_eval (a2); feclearexcept (FE_INEXACT); - /* If the result is an exact zero, ensure it has the correct - sign. */ + /* If the result is an exact zero, ensure it has the correct sign. */ if (a1 == 0 && m2 == 0) { feupdateenv (&env); - /* Ensure that round-to-nearest value of z + m1 is not - reused. */ - asm volatile ("" : "=m" (z) : "m" (z)); + /* Ensure that round-to-nearest value of z + m1 is not reused. */ + z = math_opt_barrier (z); return z + m1; } diff --git a/sysdeps/ieee754/ldbl-96/s_fmal.c b/sysdeps/ieee754/ldbl-96/s_fmal.c index 4983eda9c6..0f299da7c1 100644 --- a/sysdeps/ieee754/ldbl-96/s_fmal.c +++ b/sysdeps/ieee754/ldbl-96/s_fmal.c @@ -201,16 +201,17 @@ __fmal (long double x, long double y, long double z) t1 = m1 - t1; t2 = z - t2; long double a2 = t1 + t2; + /* Ensure the arithmetic is not scheduled after feclearexcept call. */ + math_force_eval (m2); + math_force_eval (a2); feclearexcept (FE_INEXACT); - /* If the result is an exact zero, ensure it has the correct - sign. */ + /* If the result is an exact zero, ensure it has the correct sign. */ if (a1 == 0 && m2 == 0) { feupdateenv (&env); - /* Ensure that round-to-nearest value of z + m1 is not - reused. */ - asm volatile ("" : "=m" (z) : "m" (z)); + /* Ensure that round-to-nearest value of z + m1 is not reused. */ + z = math_opt_barrier (z); return z + m1; } -- cgit 1.4.1