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authorStefan Agner <stefan.agner@toradex.com>2017-12-13 21:31:49 +0100
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2017-12-21 15:14:59 +0100
commit688f897ddd96968cf59a2d67afe2a394a0bf8ab3 (patch)
treee303dd2f94a5c670a318008c891674e116558e6b /arch/mips/math-emu/sp_fmax.c
parenta898b45a9c18bd9d723f82576a5b32a102808a09 (diff)
parentfb2d2dee504a963efdcb76517b5cdf25444cf535 (diff)
Merge remote-tracking branch 'linux-fslc/4.9-1.0.x-imx' into toradex_4.9-1.0.x-imx-next
Diffstat (limited to 'arch/mips/math-emu/sp_fmax.c')
-rw-r--r--arch/mips/math-emu/sp_fmax.c84
1 files changed, 63 insertions, 21 deletions
diff --git a/arch/mips/math-emu/sp_fmax.c b/arch/mips/math-emu/sp_fmax.c
index 4d000844e48e..74a5a00d2f22 100644
--- a/arch/mips/math-emu/sp_fmax.c
+++ b/arch/mips/math-emu/sp_fmax.c
@@ -47,14 +47,26 @@ union ieee754sp ieee754sp_fmax(union ieee754sp x, union ieee754sp y)
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
return ieee754sp_nanxcpt(x);
- /* numbers are preferred to NaNs */
+ /*
+ * Quiet NaN handling
+ */
+
+ /*
+ * The case of both inputs quiet NaNs
+ */
+ case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
+ return x;
+
+ /*
+ * The cases of exactly one input quiet NaN (numbers
+ * are here preferred as returned values to NaNs)
+ */
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
return x;
- case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
@@ -80,9 +92,7 @@ union ieee754sp ieee754sp_fmax(union ieee754sp x, union ieee754sp y)
return ys ? x : y;
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
- if (xs == ys)
- return x;
- return ieee754sp_zero(1);
+ return ieee754sp_zero(xs & ys);
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
SPDNORMX;
@@ -106,16 +116,32 @@ union ieee754sp ieee754sp_fmax(union ieee754sp x, union ieee754sp y)
else if (xs < ys)
return x;
- /* Compare exponent */
- if (xe > ye)
- return x;
- else if (xe < ye)
- return y;
+ /* Signs of inputs are equal, let's compare exponents */
+ if (xs == 0) {
+ /* Inputs are both positive */
+ if (xe > ye)
+ return x;
+ else if (xe < ye)
+ return y;
+ } else {
+ /* Inputs are both negative */
+ if (xe > ye)
+ return y;
+ else if (xe < ye)
+ return x;
+ }
- /* Compare mantissa */
+ /* Signs and exponents of inputs are equal, let's compare mantissas */
+ if (xs == 0) {
+ /* Inputs are both positive, with equal signs and exponents */
+ if (xm <= ym)
+ return y;
+ return x;
+ }
+ /* Inputs are both negative, with equal signs and exponents */
if (xm <= ym)
- return y;
- return x;
+ return x;
+ return y;
}
union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
@@ -147,14 +173,26 @@ union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
return ieee754sp_nanxcpt(x);
- /* numbers are preferred to NaNs */
+ /*
+ * Quiet NaN handling
+ */
+
+ /*
+ * The case of both inputs quiet NaNs
+ */
+ case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
+ return x;
+
+ /*
+ * The cases of exactly one input quiet NaN (numbers
+ * are here preferred as returned values to NaNs)
+ */
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
return x;
- case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
@@ -164,6 +202,9 @@ union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
/*
* Infinity and zero handling
*/
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+ return ieee754sp_inf(xs & ys);
+
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
@@ -171,7 +212,6 @@ union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
return x;
- case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
@@ -180,9 +220,7 @@ union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
return y;
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
- if (xs == ys)
- return x;
- return ieee754sp_zero(1);
+ return ieee754sp_zero(xs & ys);
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
SPDNORMX;
@@ -207,7 +245,11 @@ union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
return y;
/* Compare mantissa */
- if (xm <= ym)
+ if (xm < ym)
return y;
- return x;
+ else if (xm > ym)
+ return x;
+ else if (xs == 0)
+ return x;
+ return y;
}