Use math_narrow_eval more consistently.

Where glibc code needs to avoid excess range and precision in
floating-point arithmetic, code variously uses either asms or volatile
to force the results of that arithmetic to memory; mostly this is
conditional on FLT_EVAL_METHOD, but in the case of lrint / llrint
functions some use of volatile is unconditional (and is present
unnecessarily in versions for long double).  This patch make such code
use the recently-added math_narrow_eval macro consistently, removing
the unnecessary uses of volatile in long double lrint / llrint
implementations completely.

Tested for x86_64, x86, mips64 and powerpc.

	* math/s_nexttowardf.c (__nexttowardf): Use math_narrow_eval.
	* stdlib/strtod_l.c: Include <math_private.h>.
	(overflow_value): Use math_narrow_eval.
	(underflow_value): Likewise.
	* sysdeps/i386/fpu/s_nexttoward.c (__nexttoward): Likewise.
	* sysdeps/i386/fpu/s_nexttowardf.c (__nexttowardf): Likewise.
	* sysdeps/ieee754/dbl-64/e_gamma_r.c (gamma_positive): Likewise.
	(__ieee754_gamma_r): Likewise.
	* sysdeps/ieee754/dbl-64/gamma_productf.c (__gamma_productf):
	Likewise.
	* sysdeps/ieee754/dbl-64/k_rem_pio2.c (__kernel_rem_pio2):
	Likewise.
	* sysdeps/ieee754/dbl-64/lgamma_neg.c (__lgamma_neg): Likewise.
	* sysdeps/ieee754/dbl-64/s_erf.c (__erfc): Likewise.
	* sysdeps/ieee754/dbl-64/s_llrint.c (__llrint): Likewise.
	* sysdeps/ieee754/dbl-64/s_lrint.c (__lrint): Likewise.
	* sysdeps/ieee754/flt-32/e_gammaf_r.c (gammaf_positive): Likewise.
	(__ieee754_gammaf_r): Likewise.
	* sysdeps/ieee754/flt-32/k_rem_pio2f.c (__kernel_rem_pio2f):
	Likewise.
	* sysdeps/ieee754/flt-32/lgamma_negf.c (__lgamma_negf): Likewise.
	* sysdeps/ieee754/flt-32/s_erff.c (__erfcf): Likewise.
	* sysdeps/ieee754/flt-32/s_llrintf.c (__llrintf): Likewise.
	* sysdeps/ieee754/flt-32/s_lrintf.c (__lrintf): Likewise.
	* sysdeps/ieee754/ldbl-128/s_llrintl.c (__llrintl): Do not use
	volatile.
	* sysdeps/ieee754/ldbl-128/s_lrintl.c (__lrintl): Likewise.
	* sysdeps/ieee754/ldbl-128/s_nexttoward.c (__nexttoward): Use
	math_narrow_eval.
	* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward):
	Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf):
	Likewise.
	* sysdeps/ieee754/ldbl-96/gamma_product.c (__gamma_product):
	Likewise.
	* sysdeps/ieee754/ldbl-96/s_llrintl.c (__llrintl): Do not use
	volatile.
	* sysdeps/ieee754/ldbl-96/s_lrintl.c (__lrintl): Likewise.
	* sysdeps/ieee754/ldbl-96/s_nexttoward.c (__nexttoward): Use
	math_narrow_eval.
	* sysdeps/ieee754/ldbl-96/s_nexttowardf.c (__nexttowardf):
	Likewise.
	* sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c (__nldbl_nexttowardf):
	Likewise.

29 files changed, 109 insertions, 158 deletions

diff --git a/ChangeLog b/ChangeLog
index 0ae05c8c48..3a5f03d738 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,50 @@
+2015-09-23  Joseph Myers  <joseph@codesourcery.com>
+
+	* math/s_nexttowardf.c (__nexttowardf): Use math_narrow_eval.
+	* stdlib/strtod_l.c: Include <math_private.h>.
+	(overflow_value): Use math_narrow_eval.
+	(underflow_value): Likewise.
+	* sysdeps/i386/fpu/s_nexttoward.c (__nexttoward): Likewise.
+	* sysdeps/i386/fpu/s_nexttowardf.c (__nexttowardf): Likewise.
+	* sysdeps/ieee754/dbl-64/e_gamma_r.c (gamma_positive): Likewise.
+	(__ieee754_gamma_r): Likewise.
+	* sysdeps/ieee754/dbl-64/gamma_productf.c (__gamma_productf):
+	Likewise.
+	* sysdeps/ieee754/dbl-64/k_rem_pio2.c (__kernel_rem_pio2):
+	Likewise.
+	* sysdeps/ieee754/dbl-64/lgamma_neg.c (__lgamma_neg): Likewise.
+	* sysdeps/ieee754/dbl-64/s_erf.c (__erfc): Likewise.
+	* sysdeps/ieee754/dbl-64/s_llrint.c (__llrint): Likewise.
+	* sysdeps/ieee754/dbl-64/s_lrint.c (__lrint): Likewise.
+	* sysdeps/ieee754/flt-32/e_gammaf_r.c (gammaf_positive): Likewise.
+	(__ieee754_gammaf_r): Likewise.
+	* sysdeps/ieee754/flt-32/k_rem_pio2f.c (__kernel_rem_pio2f):
+	Likewise.
+	* sysdeps/ieee754/flt-32/lgamma_negf.c (__lgamma_negf): Likewise.
+	* sysdeps/ieee754/flt-32/s_erff.c (__erfcf): Likewise.
+	* sysdeps/ieee754/flt-32/s_llrintf.c (__llrintf): Likewise.
+	* sysdeps/ieee754/flt-32/s_lrintf.c (__lrintf): Likewise.
+	* sysdeps/ieee754/ldbl-128/s_llrintl.c (__llrintl): Do not use
+	volatile.
+	* sysdeps/ieee754/ldbl-128/s_lrintl.c (__lrintl): Likewise.
+	* sysdeps/ieee754/ldbl-128/s_nexttoward.c (__nexttoward): Use
+	math_narrow_eval.
+	* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward):
+	Likewise.
+	* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf):
+	Likewise.
+	* sysdeps/ieee754/ldbl-96/gamma_product.c (__gamma_product):
+	Likewise.
+	* sysdeps/ieee754/ldbl-96/s_llrintl.c (__llrintl): Do not use
+	volatile.
+	* sysdeps/ieee754/ldbl-96/s_lrintl.c (__lrintl): Likewise.
+	* sysdeps/ieee754/ldbl-96/s_nexttoward.c (__nexttoward): Use
+	math_narrow_eval.
+	* sysdeps/ieee754/ldbl-96/s_nexttowardf.c (__nexttowardf):
+	Likewise.
+	* sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c (__nldbl_nexttowardf):
+	Likewise.
+
 2015-09-22  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* nptl/Versions: Remove ignored symbols.
diff --git a/math/s_nexttowardf.c b/math/s_nexttowardf.c
index e8c4dd1d8d..06e1bb10cb 100644
--- a/math/s_nexttowardf.c
+++ b/math/s_nexttowardf.c
@@ -59,10 +59,7 @@ float __nexttowardf(float x, long double y)
 	}
 	hy = hx&0x7f800000;
 	if(hy>=0x7f800000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0)
-	    /* Force conversion to float.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00800000) {
diff --git a/stdlib/strtod_l.c b/stdlib/strtod_l.c
index e13ab1e7e1..7950870270 100644
--- a/stdlib/strtod_l.c
+++ b/stdlib/strtod_l.c
@@ -57,6 +57,7 @@ extern unsigned long long int ____strtoull_l_internal (const char *, char **,
 #include "../locale/localeinfo.h"
 #include <locale.h>
 #include <math.h>
+#include <math_private.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdint.h>
@@ -181,10 +182,8 @@ static FLOAT
 overflow_value (int negative)
 {
   __set_errno (ERANGE);
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
-  FLOAT result = (negative ? -MAX_VALUE : MAX_VALUE) * MAX_VALUE;
+  FLOAT result = math_narrow_eval ((negative ? -MAX_VALUE : MAX_VALUE)
+				   * MAX_VALUE);
   return result;
 }
 
@@ -195,10 +194,8 @@ static FLOAT
 underflow_value (int negative)
 {
   __set_errno (ERANGE);
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
-  FLOAT result = (negative ? -MIN_VALUE : MIN_VALUE) * MIN_VALUE;
+  FLOAT result = math_narrow_eval ((negative ? -MIN_VALUE : MIN_VALUE)
+				   * MIN_VALUE);
   return result;
 }
 
diff --git a/sysdeps/i386/fpu/s_nexttoward.c b/sysdeps/i386/fpu/s_nexttoward.c
index 74147c4f9e..be65b8ce29 100644
--- a/sysdeps/i386/fpu/s_nexttoward.c
+++ b/sysdeps/i386/fpu/s_nexttoward.c
@@ -73,10 +73,7 @@ double __nexttoward(double x, long double y)
 	}
 	hy = hx&0x7ff00000;
 	if(hy>=0x7ff00000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0 && FLT_EVAL_METHOD != 1)
-	    /* Force conversion to double.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00100000) {
diff --git a/sysdeps/i386/fpu/s_nexttowardf.c b/sysdeps/i386/fpu/s_nexttowardf.c
index 49651bed6f..8379eff8b8 100644
--- a/sysdeps/i386/fpu/s_nexttowardf.c
+++ b/sysdeps/i386/fpu/s_nexttowardf.c
@@ -61,10 +61,7 @@ float __nexttowardf(float x, long double y)
 	}
 	hy = hx&0x7f800000;
 	if(hy>=0x7f800000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0)
-	    /* Force conversion to float.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00800000) {
diff --git a/sysdeps/ieee754/dbl-64/e_gamma_r.c b/sysdeps/ieee754/dbl-64/e_gamma_r.c
index d1acaa6a12..d3fb8af97e 100644
--- a/sysdeps/ieee754/dbl-64/e_gamma_r.c
+++ b/sysdeps/ieee754/dbl-64/e_gamma_r.c
@@ -76,11 +76,7 @@ gamma_positive (double x, int *exp2_adj)
 	  /* Adjust into the range for applying Stirling's
 	     approximation.  */
 	  double n = __ceil (12.0 - x);
-#if FLT_EVAL_METHOD != 0
-	  volatile
-#endif
-	  double x_tmp = x + n;
-	  x_adj = x_tmp;
+	  x_adj = math_narrow_eval (x + n);
 	  x_eps = (x - (x_adj - n));
 	  prod = __gamma_product (x_adj - n, x_eps, n, &eps);
 	}
@@ -119,9 +115,6 @@ __ieee754_gamma_r (double x, int *signgamp)
 {
   int32_t hx;
   u_int32_t lx;
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
   double ret;
 
   EXTRACT_WORDS (hx, lx, x);
@@ -157,7 +150,7 @@ __ieee754_gamma_r (double x, int *signgamp)
     {
       /* Overflow.  */
       *signgamp = 0;
-      ret = DBL_MAX * DBL_MAX;
+      ret = math_narrow_eval (DBL_MAX * DBL_MAX);
       return ret;
     }
   else
@@ -201,27 +194,28 @@ __ieee754_gamma_r (double x, int *signgamp)
 		}
 	    }
 	}
+      ret = math_narrow_eval (ret);
     }
   if (isinf (ret) && x != 0)
     {
       if (*signgamp < 0)
 	{
-	  ret = -__copysign (DBL_MAX, ret) * DBL_MAX;
+	  ret = math_narrow_eval (-__copysign (DBL_MAX, ret) * DBL_MAX);
 	  ret = -ret;
 	}
       else
-	ret = __copysign (DBL_MAX, ret) * DBL_MAX;
+	ret = math_narrow_eval (__copysign (DBL_MAX, ret) * DBL_MAX);
       return ret;
     }
   else if (ret == 0)
     {
       if (*signgamp < 0)
 	{
-	  ret = -__copysign (DBL_MIN, ret) * DBL_MIN;
+	  ret = math_narrow_eval (-__copysign (DBL_MIN, ret) * DBL_MIN);
 	  ret = -ret;
 	}
       else
-	ret = __copysign (DBL_MIN, ret) * DBL_MIN;
+	ret = math_narrow_eval (__copysign (DBL_MIN, ret) * DBL_MIN);
       return ret;
     }
   else
diff --git a/sysdeps/ieee754/dbl-64/gamma_productf.c b/sysdeps/ieee754/dbl-64/gamma_productf.c
index df59e1beec..2d3c73442b 100644
--- a/sysdeps/ieee754/dbl-64/gamma_productf.c
+++ b/sysdeps/ieee754/dbl-64/gamma_productf.c
@@ -36,10 +36,7 @@ __gamma_productf (float x, float x_eps, int n, float *eps)
   for (int i = 1; i < n; i++)
     ret *= x_full + i;
 
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
-  float fret = ret;
+  float fret = math_narrow_eval ((float) ret);
   *eps = (ret - fret) / fret;
 
   return fret;
diff --git a/sysdeps/ieee754/dbl-64/k_rem_pio2.c b/sysdeps/ieee754/dbl-64/k_rem_pio2.c
index 047c6c2886..e58c9e854c 100644
--- a/sysdeps/ieee754/dbl-64/k_rem_pio2.c
+++ b/sysdeps/ieee754/dbl-64/k_rem_pio2.c
@@ -315,34 +315,25 @@ recompute:
       break;
     case 1:
     case 2:;
-#if __FLT_EVAL_METHOD__ != 0
-      volatile
-#endif
       double fv = 0.0;
       for (i = jz; i >= 0; i--)
-	fv += fq[i];
+	fv = math_narrow_eval (fv + fq[i]);
       y[0] = (ih == 0) ? fv : -fv;
-      fv = fq[0] - fv;
+      fv = math_narrow_eval (fq[0] - fv);
       for (i = 1; i <= jz; i++)
-	fv += fq[i];
+	fv = math_narrow_eval (fv + fq[i]);
       y[1] = (ih == 0) ? fv : -fv;
       break;
     case 3:             /* painful */
       for (i = jz; i > 0; i--)
 	{
-#if __FLT_EVAL_METHOD__ != 0
-	  volatile
-#endif
-	  double fv = (double) (fq[i - 1] + fq[i]);
+	  double fv = math_narrow_eval (fq[i - 1] + fq[i]);
 	  fq[i] += fq[i - 1] - fv;
 	  fq[i - 1] = fv;
 	}
       for (i = jz; i > 1; i--)
 	{
-#if __FLT_EVAL_METHOD__ != 0
-	  volatile
-#endif
-	  double fv = (double) (fq[i - 1] + fq[i]);
+	  double fv = math_narrow_eval (fq[i - 1] + fq[i]);
 	  fq[i] += fq[i - 1] - fv;
 	  fq[i - 1] = fv;
 	}
diff --git a/sysdeps/ieee754/dbl-64/lgamma_neg.c b/sysdeps/ieee754/dbl-64/lgamma_neg.c
index 8f54a0f98e..9544600015 100644
--- a/sysdeps/ieee754/dbl-64/lgamma_neg.c
+++ b/sysdeps/ieee754/dbl-64/lgamma_neg.c
@@ -330,17 +330,9 @@ __lgamma_neg (double x, int *signgamp)
     }
 
   double log_gamma_ratio;
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
-  double y0_tmp = 1 - x0_hi;
-  double y0 = y0_tmp;
+  double y0 = math_narrow_eval (1 - x0_hi);
   double y0_eps = -x0_hi + (1 - y0) - x0_lo;
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
-  double y_tmp = 1 - x;
-  double y = y_tmp;
+  double y = math_narrow_eval (1 - x);
   double y_eps = -x + (1 - y);
   /* We now wish to compute LOG_GAMMA_RATIO
      = log (gamma (Y0 + Y0_EPS) / gamma (Y + Y_EPS)).  XDIFF
@@ -353,19 +345,11 @@ __lgamma_neg (double x, int *signgamp)
     {
       int n_up = (7 - i) / 2;
       double ny0, ny0_eps, ny, ny_eps;
-#if FLT_EVAL_METHOD != 0
-      volatile
-#endif
-      double y0_tmp = y0 + n_up;
-      ny0 = y0_tmp;
+      ny0 = math_narrow_eval (y0 + n_up);
       ny0_eps = y0 - (ny0 - n_up) + y0_eps;
       y0 = ny0;
       y0_eps = ny0_eps;
-#if FLT_EVAL_METHOD != 0
-      volatile
-#endif
-      double y_tmp = y + n_up;
-      ny = y_tmp;
+      ny = math_narrow_eval (y + n_up);
       ny_eps = y - (ny - n_up) + y_eps;
       y = ny;
       y_eps = ny_eps;
diff --git a/sysdeps/ieee754/dbl-64/s_erf.c b/sysdeps/ieee754/dbl-64/s_erf.c
index ea0a73424e..77cd50d935 100644
--- a/sysdeps/ieee754/dbl-64/s_erf.c
+++ b/sysdeps/ieee754/dbl-64/s_erf.c
@@ -402,10 +402,7 @@ __erfc (double x)
 	  __ieee754_exp ((z - x) * (z + x) + R / S);
       if (hx > 0)
 	{
-#if FLT_EVAL_METHOD != 0
-	  volatile
-#endif
-	  double ret = r / x;
+	  double ret = math_narrow_eval (r / x);
 	  if (ret == 0)
 	    __set_errno (ERANGE);
 	  return ret;
diff --git a/sysdeps/ieee754/dbl-64/s_llrint.c b/sysdeps/ieee754/dbl-64/s_llrint.c
index 62acb67c38..048331e9a7 100644
--- a/sysdeps/ieee754/dbl-64/s_llrint.c
+++ b/sysdeps/ieee754/dbl-64/s_llrint.c
@@ -35,7 +35,7 @@ __llrint (double x)
   int32_t j0;
   u_int32_t i1, i0;
   long long int result;
-  volatile double w;
+  double w;
   double t;
   int sx;
 
@@ -47,7 +47,7 @@ __llrint (double x)
 
   if (j0 < 20)
     {
-      w = two52[sx] + x;
+      w = math_narrow_eval (two52[sx] + x);
       t = w - two52[sx];
       EXTRACT_WORDS (i0, i1, t);
       j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
@@ -62,7 +62,7 @@ __llrint (double x)
 	result = (((long long int) i0 << 32) | i1) << (j0 - 52);
       else
 	{
-	  w = two52[sx] + x;
+	  w = math_narrow_eval (two52[sx] + x);
 	  t = w - two52[sx];
 	  EXTRACT_WORDS (i0, i1, t);
 	  j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
diff --git a/sysdeps/ieee754/dbl-64/s_lrint.c b/sysdeps/ieee754/dbl-64/s_lrint.c
index 9cce37f3cf..353d5f503b 100644
--- a/sysdeps/ieee754/dbl-64/s_lrint.c
+++ b/sysdeps/ieee754/dbl-64/s_lrint.c
@@ -34,7 +34,7 @@ __lrint (double x)
 {
   int32_t j0;
   u_int32_t i0, i1;
-  volatile double w;
+  double w;
   double t;
   long int result;
   int sx;
@@ -47,7 +47,7 @@ __lrint (double x)
 
   if (j0 < 20)
     {
-      w = two52[sx] + x;
+      w = math_narrow_eval (two52[sx] + x);
       t = w - two52[sx];
       EXTRACT_WORDS (i0, i1, t);
       j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
@@ -62,7 +62,7 @@ __lrint (double x)
 	result = ((long int) i0 << (j0 - 20)) | (i1 << (j0 - 52));
       else
 	{
-	  w = two52[sx] + x;
+	  w = math_narrow_eval (two52[sx] + x);
 	  t = w - two52[sx];
 	  EXTRACT_WORDS (i0, i1, t);
 	  j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
diff --git a/sysdeps/ieee754/flt-32/e_gammaf_r.c b/sysdeps/ieee754/flt-32/e_gammaf_r.c
index 250e412aa7..183db1e033 100644
--- a/sysdeps/ieee754/flt-32/e_gammaf_r.c
+++ b/sysdeps/ieee754/flt-32/e_gammaf_r.c
@@ -69,11 +69,7 @@ gammaf_positive (float x, int *exp2_adj)
 	  /* Adjust into the range for applying Stirling's
 	     approximation.  */
 	  float n = __ceilf (4.0f - x);
-#if FLT_EVAL_METHOD != 0
-	  volatile
-#endif
-	  float x_tmp = x + n;
-	  x_adj = x_tmp;
+	  x_adj = math_narrow_eval (x + n);
 	  x_eps = (x - (x_adj - n));
 	  prod = __gamma_productf (x_adj - n, x_eps, n, &eps);
 	}
@@ -111,9 +107,6 @@ float
 __ieee754_gammaf_r (float x, int *signgamp)
 {
   int32_t hx;
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
   float ret;
 
   GET_FLOAT_WORD (hx, x);
@@ -149,7 +142,7 @@ __ieee754_gammaf_r (float x, int *signgamp)
     {
       /* Overflow.  */
       *signgamp = 0;
-      ret = FLT_MAX * FLT_MAX;
+      ret = math_narrow_eval (FLT_MAX * FLT_MAX);
       return ret;
     }
   else
@@ -193,27 +186,28 @@ __ieee754_gammaf_r (float x, int *signgamp)
 		}
 	    }
 	}
+      ret = math_narrow_eval (ret);
     }
   if (isinf (ret) && x != 0)
     {
       if (*signgamp < 0)
 	{
-	  ret = -__copysignf (FLT_MAX, ret) * FLT_MAX;
+	  ret = math_narrow_eval (-__copysignf (FLT_MAX, ret) * FLT_MAX);
 	  ret = -ret;
 	}
       else
-	ret = __copysignf (FLT_MAX, ret) * FLT_MAX;
+	ret = math_narrow_eval (__copysignf (FLT_MAX, ret) * FLT_MAX);
       return ret;
     }
   else if (ret == 0)
     {
       if (*signgamp < 0)
 	{
-	  ret = -__copysignf (FLT_MIN, ret) * FLT_MIN;
+	  ret = math_narrow_eval (-__copysignf (FLT_MIN, ret) * FLT_MIN);
 	  ret = -ret;
 	}
       else
-	ret = __copysignf (FLT_MIN, ret) * FLT_MIN;
+	ret = math_narrow_eval (__copysignf (FLT_MIN, ret) * FLT_MIN);
       return ret;
     }
   else
diff --git a/sysdeps/ieee754/flt-32/k_rem_pio2f.c b/sysdeps/ieee754/flt-32/k_rem_pio2f.c
index 6f14d5bac7..0c7685c3ab 100644
--- a/sysdeps/ieee754/flt-32/k_rem_pio2f.c
+++ b/sysdeps/ieee754/flt-32/k_rem_pio2f.c
@@ -167,30 +167,21 @@ recompute:
 		break;
 	    case 1:
 	    case 2:;
-#if __FLT_EVAL_METHOD__ != 0
-		volatile
-#endif
 		float fv = 0.0;
-		for (i=jz;i>=0;i--) fv += fq[i];
+		for (i=jz;i>=0;i--) fv = math_narrow_eval (fv + fq[i]);
 		y[0] = (ih==0)? fv: -fv;
-		fv = fq[0]-fv;
-		for (i=1;i<=jz;i++) fv += fq[i];
+		fv = math_narrow_eval (fq[0]-fv);
+		for (i=1;i<=jz;i++) fv = math_narrow_eval (fv + fq[i]);
 		y[1] = (ih==0)? fv: -fv;
 		break;
 	    case 3:	/* painful */
 		for (i=jz;i>0;i--) {
-#if __FLT_EVAL_METHOD__ != 0
-		    volatile
-#endif
-		    float fv = fq[i-1]+fq[i];
+		    float fv = math_narrow_eval (fq[i-1]+fq[i]);
 		    fq[i]  += fq[i-1]-fv;
 		    fq[i-1] = fv;
 		}
 		for (i=jz;i>1;i--) {
-#if __FLT_EVAL_METHOD__ != 0
-		    volatile
-#endif
-		    float fv = fq[i-1]+fq[i];
+		    float fv = math_narrow_eval (fq[i-1]+fq[i]);
 		    fq[i]  += fq[i-1]-fv;
 		    fq[i-1] = fv;
 		}
diff --git a/sysdeps/ieee754/flt-32/lgamma_negf.c b/sysdeps/ieee754/flt-32/lgamma_negf.c
index ed9659801e..68bee8572a 100644
--- a/sysdeps/ieee754/flt-32/lgamma_negf.c
+++ b/sysdeps/ieee754/flt-32/lgamma_negf.c
@@ -245,17 +245,9 @@ __lgamma_negf (float x, int *signgamp)
     }
 
   float log_gamma_ratio;
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
-  float y0_tmp = 1 - x0_hi;
-  float y0 = y0_tmp;
+  float y0 = math_narrow_eval (1 - x0_hi);
   float y0_eps = -x0_hi + (1 - y0) - x0_lo;
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
-  float y_tmp = 1 - x;
-  float y = y_tmp;
+  float y = math_narrow_eval (1 - x);
   float y_eps = -x + (1 - y);
   /* We now wish to compute LOG_GAMMA_RATIO
      = log (gamma (Y0 + Y0_EPS) / gamma (Y + Y_EPS)).  XDIFF
diff --git a/sysdeps/ieee754/flt-32/s_erff.c b/sysdeps/ieee754/flt-32/s_erff.c
index 2be44cc40c..1aabce5cb8 100644
--- a/sysdeps/ieee754/flt-32/s_erff.c
+++ b/sysdeps/ieee754/flt-32/s_erff.c
@@ -213,10 +213,7 @@ float __erfcf(float x)
 	    r  =  __ieee754_expf(-z*z-(float)0.5625)*
 			__ieee754_expf((z-x)*(z+x)+R/S);
 	    if(hx>0) {
-#if FLT_EVAL_METHOD != 0
-		volatile
-#endif
-		float ret = r/x;
+		float ret = math_narrow_eval (r/x);
 		if (ret == 0)
 		    __set_errno (ERANGE);
 		return ret;
diff --git a/sysdeps/ieee754/flt-32/s_llrintf.c b/sysdeps/ieee754/flt-32/s_llrintf.c
index ac8c1a2216..d7588d04cf 100644
--- a/sysdeps/ieee754/flt-32/s_llrintf.c
+++ b/sysdeps/ieee754/flt-32/s_llrintf.c
@@ -34,7 +34,7 @@ __llrintf (float x)
 {
   int32_t j0;
   u_int32_t i0;
-  volatile float w;
+  float w;
   float t;
   long long int result;
   int sx;
@@ -52,7 +52,7 @@ __llrintf (float x)
 	result = (long long int) i0 << (j0 - 23);
       else
 	{
-	  w = two23[sx] + x;
+	  w = math_narrow_eval (two23[sx] + x);
 	  t = w - two23[sx];
 	  GET_FLOAT_WORD (i0, t);
 	  j0 = ((i0 >> 23) & 0xff) - 0x7f;
diff --git a/sysdeps/ieee754/flt-32/s_lrintf.c b/sysdeps/ieee754/flt-32/s_lrintf.c
index 7581a8d286..bc60fd2311 100644
--- a/sysdeps/ieee754/flt-32/s_lrintf.c
+++ b/sysdeps/ieee754/flt-32/s_lrintf.c
@@ -34,7 +34,7 @@ __lrintf (float x)
 {
   int32_t j0;
   u_int32_t i0;
-  volatile float w;
+  float w;
   float t;
   long int result;
   int sx;
@@ -52,7 +52,7 @@ __lrintf (float x)
 	result = (long int) i0 << (j0 - 23);
       else
 	{
-	  w = two23[sx] + x;
+	  w = math_narrow_eval (two23[sx] + x);
 	  t = w - two23[sx];
 	  GET_FLOAT_WORD (i0, t);
 	  j0 = ((i0 >> 23) & 0xff) - 0x7f;
diff --git a/sysdeps/ieee754/ldbl-128/s_llrintl.c b/sysdeps/ieee754/ldbl-128/s_llrintl.c
index 27196c95a4..77eb2d67e9 100644
--- a/sysdeps/ieee754/ldbl-128/s_llrintl.c
+++ b/sysdeps/ieee754/ldbl-128/s_llrintl.c
@@ -34,7 +34,7 @@ __llrintl (long double x)
 {
   int32_t j0;
   u_int64_t i0,i1;
-  volatile long double w;
+  long double w;
   long double t;
   long long int result;
   int sx;
diff --git a/sysdeps/ieee754/ldbl-128/s_lrintl.c b/sysdeps/ieee754/ldbl-128/s_lrintl.c
index dc678d585d..b0e0cfc16b 100644
--- a/sysdeps/ieee754/ldbl-128/s_lrintl.c
+++ b/sysdeps/ieee754/ldbl-128/s_lrintl.c
@@ -34,7 +34,7 @@ __lrintl (long double x)
 {
   int32_t j0;
   u_int64_t i0,i1;
-  volatile long double w;
+  long double w;
   long double t;
   long int result;
   int sx;
diff --git a/sysdeps/ieee754/ldbl-128/s_nexttoward.c b/sysdeps/ieee754/ldbl-128/s_nexttoward.c
index 2cd2e58391..e62ca3fef8 100644
--- a/sysdeps/ieee754/ldbl-128/s_nexttoward.c
+++ b/sysdeps/ieee754/ldbl-128/s_nexttoward.c
@@ -73,10 +73,7 @@ double __nexttoward(double x, long double y)
 	}
 	hy = hx&0x7ff00000;
 	if(hy>=0x7ff00000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0 && FLT_EVAL_METHOD != 1)
-	    /* Force conversion to double.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00100000) {
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c b/sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c
index b40cf167f3..85140c1d02 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c
@@ -74,10 +74,7 @@ double __nexttoward(double x, long double y)
 	}
 	hy = hx&0x7ff00000;
 	if(hy>=0x7ff00000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0 && FLT_EVAL_METHOD != 1)
-	    /* Force conversion to double.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00100000) {
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c b/sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c
index 19522f4762..b27f0bb380 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c
@@ -63,10 +63,7 @@ float __nexttowardf(float x, long double y)
 	}
 	hy = hx&0x7f800000;
 	if(hy>=0x7f800000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0)
-	    /* Force conversion to float.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00800000) {		/* underflow */
diff --git a/sysdeps/ieee754/ldbl-96/gamma_product.c b/sysdeps/ieee754/ldbl-96/gamma_product.c
index e113e23723..ff95b73385 100644
--- a/sysdeps/ieee754/ldbl-96/gamma_product.c
+++ b/sysdeps/ieee754/ldbl-96/gamma_product.c
@@ -36,10 +36,7 @@ __gamma_product (double x, double x_eps, int n, double *eps)
   for (int i = 1; i < n; i++)
     ret *= x_full + i;
 
-#if FLT_EVAL_METHOD != 0
-  volatile
-#endif
-  double fret = ret;
+  double fret = math_narrow_eval ((double) ret);
   *eps = (ret - fret) / fret;
 
   return fret;
diff --git a/sysdeps/ieee754/ldbl-96/s_llrintl.c b/sysdeps/ieee754/ldbl-96/s_llrintl.c
index 070246cb6a..c73741e53e 100644
--- a/sysdeps/ieee754/ldbl-96/s_llrintl.c
+++ b/sysdeps/ieee754/ldbl-96/s_llrintl.c
@@ -35,7 +35,7 @@ __llrintl (long double x)
   int32_t se,j0;
   u_int32_t i0, i1;
   long long int result;
-  volatile long double w;
+  long double w;
   long double t;
   int sx;
 
diff --git a/sysdeps/ieee754/ldbl-96/s_lrintl.c b/sysdeps/ieee754/ldbl-96/s_lrintl.c
index 96c6a5ea7d..598423b90b 100644
--- a/sysdeps/ieee754/ldbl-96/s_lrintl.c
+++ b/sysdeps/ieee754/ldbl-96/s_lrintl.c
@@ -35,7 +35,7 @@ __lrintl (long double x)
   int32_t se,j0;
   u_int32_t i0, i1;
   long int result;
-  volatile long double w;
+  long double w;
   long double t;
   int sx;
 
diff --git a/sysdeps/ieee754/ldbl-96/s_nexttoward.c b/sysdeps/ieee754/ldbl-96/s_nexttoward.c
index f7a8b2165a..b972a3eb3a 100644
--- a/sysdeps/ieee754/ldbl-96/s_nexttoward.c
+++ b/sysdeps/ieee754/ldbl-96/s_nexttoward.c
@@ -70,10 +70,7 @@ double __nexttoward(double x, long double y)
 	}
 	hy = hx&0x7ff00000;
 	if(hy>=0x7ff00000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0 && FLT_EVAL_METHOD != 1)
-	    /* Force conversion to double.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00100000) {
diff --git a/sysdeps/ieee754/ldbl-96/s_nexttowardf.c b/sysdeps/ieee754/ldbl-96/s_nexttowardf.c
index a96f9da2c2..f1fe4e7ca7 100644
--- a/sysdeps/ieee754/ldbl-96/s_nexttowardf.c
+++ b/sysdeps/ieee754/ldbl-96/s_nexttowardf.c
@@ -58,10 +58,7 @@ float __nexttowardf(float x, long double y)
 	}
 	hy = hx&0x7f800000;
 	if(hy>=0x7f800000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0)
-	    /* Force conversion to float.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00800000) {
diff --git a/sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c b/sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c
index 7eca121701..782e1a3340 100644
--- a/sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c
+++ b/sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c
@@ -62,10 +62,7 @@ float __nldbl_nexttowardf(float x, double y)
 	}
 	hy = hx&0x7f800000;
 	if(hy>=0x7f800000) {
-	  x = x+x;	/* overflow  */
-	  if (FLT_EVAL_METHOD != 0)
-	    /* Force conversion to float.  */
-	    asm ("" : "+m"(x));
+	  x = math_narrow_eval (x+x);	/* overflow  */
 	  return x;
 	}
 	if(hy<0x00800000) {