summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authornsz <nsz@port70.net>2012-05-06 21:24:28 +0200
committernsz <nsz@port70.net>2012-05-06 21:24:28 +0200
commit6ab8136b4477fd75381c06fa0e7fa93c89c712a1 (patch)
treefea8ff7bf34e2a41e797528571d62097413b3685
parent4e597feef0595caefa39ab43c813734a1244fa84 (diff)
downloadmusl-6ab8136b4477fd75381c06fa0e7fa93c89c712a1.tar.gz
add FORCE_EVAL macro to evaluate float expr for their side effect
updated nextafter* to use FORCE_EVAL, it can be used in many other places in the math code to improve readability.
-rw-r--r--src/internal/libm.h13
-rw-r--r--src/math/nextafter.c6
-rw-r--r--src/math/nextafterf.c6
-rw-r--r--src/math/nextafterl.c12
-rw-r--r--src/math/nexttoward.c6
-rw-r--r--src/math/nexttowardf.c6
6 files changed, 25 insertions, 24 deletions
diff --git a/src/internal/libm.h b/src/internal/libm.h
index 8c5474a8..a71c4c05 100644
--- a/src/internal/libm.h
+++ b/src/internal/libm.h
@@ -32,6 +32,19 @@ union dshape {
uint64_t bits;
};
+#define FORCE_EVAL(x) do { \
+ if (sizeof(x) == sizeof(float)) { \
+ volatile float __x; \
+ __x = (x); \
+ } else if (sizeof(x) == sizeof(double)) { \
+ volatile double __x; \
+ __x = (x); \
+ } else { \
+ volatile long double __x; \
+ __x = (x); \
+ } \
+} while(0)
+
/* Get two 32 bit ints from a double. */
#define EXTRACT_WORDS(hi,lo,d) \
do { \
diff --git a/src/math/nextafter.c b/src/math/nextafter.c
index e4bfb022..a3b42c99 100644
--- a/src/math/nextafter.c
+++ b/src/math/nextafter.c
@@ -29,9 +29,7 @@ double nextafter(double x, double y)
if (e == 0x7ff)
return x + x;
/* raise underflow if ux.value is subnormal or zero */
- if (e == 0) {
- volatile double z;
- z = x*x + ux.value*ux.value;
- }
+ if (e == 0)
+ FORCE_EVAL(x*x + ux.value*ux.value);
return ux.value;
}
diff --git a/src/math/nextafterf.c b/src/math/nextafterf.c
index 47775b92..b703487b 100644
--- a/src/math/nextafterf.c
+++ b/src/math/nextafterf.c
@@ -28,9 +28,7 @@ float nextafterf(float x, float y)
if (e == 0x7f800000)
return x + x;
/* raise underflow if ux.value is subnormal or zero */
- if (e == 0) {
- volatile float z;
- z = x*x + ux.value*ux.value;
- }
+ if (e == 0)
+ FORCE_EVAL(x*x + ux.value*ux.value);
return ux.value;
}
diff --git a/src/math/nextafterl.c b/src/math/nextafterl.c
index c09d9dd0..edc3cc9c 100644
--- a/src/math/nextafterl.c
+++ b/src/math/nextafterl.c
@@ -38,10 +38,8 @@ long double nextafterl(long double x, long double y)
if (ux.bits.exp == 0x7fff)
return x + x;
/* raise underflow if ux.value is subnormal or zero */
- if (ux.bits.exp == 0) {
- volatile float z;
- z = x*x + ux.value*ux.value;
- }
+ if (ux.bits.exp == 0)
+ FORCE_EVAL(x*x + ux.value*ux.value);
return ux.value;
}
#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
@@ -77,10 +75,8 @@ long double nextafterl(long double x, long double y)
if (ux.bits.exp == 0x7fff)
return x + x;
/* raise underflow if ux.value is subnormal or zero */
- if (ux.bits.exp == 0) {
- volatile float z;
- z = x*x + ux.value*ux.value;
- }
+ if (ux.bits.exp == 0)
+ FORCE_EVAL(x*x + ux.value*ux.value);
return ux.value;
}
#endif
diff --git a/src/math/nexttoward.c b/src/math/nexttoward.c
index 43f8fee8..7355f2f1 100644
--- a/src/math/nexttoward.c
+++ b/src/math/nexttoward.c
@@ -38,10 +38,8 @@ double nexttoward(double x, long double y)
if (e == 0x7ff)
return x + x;
/* raise underflow if ux.value is subnormal or zero */
- if (e == 0) {
- volatile float z;
- z = x*x + ux.value*ux.value;
- }
+ if (e == 0)
+ FORCE_EVAL(x*x + ux.value*ux.value);
return ux.value;
}
#endif
diff --git a/src/math/nexttowardf.c b/src/math/nexttowardf.c
index e8e6f676..8648be6a 100644
--- a/src/math/nexttowardf.c
+++ b/src/math/nexttowardf.c
@@ -30,9 +30,7 @@ float nexttowardf(float x, long double y)
if (e == 0x7f800000)
return x + x;
/* raise underflow if ux.value is subnormal or zero */
- if (e == 0) {
- volatile float z;
- z = x*x + ux.value*ux.value;
- }
+ if (e == 0)
+ FORCE_EVAL(x*x + ux.value*ux.value);
return ux.value;
}