softfloat: Handle float_muladd_negate_c when product is zero
Honour float_muladd_negate_c in the case where the product is zero and
c is nonzero. Previously we would fail to negate c.
Seen in (and tested against) the gfortran testsuite on MIPS.
Signed-off-by: Richard Sandiford <rdsandiford@googlemail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index ac3d150..83ccc4b 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -2234,7 +2234,7 @@
}
}
/* Zero plus something non-zero : just return the something */
- return make_float32(float32_val(c) ^ (signflip << 31));
+ return packFloat32(cSign ^ signflip, cExp, cSig);
}
if (aExp == 0) {
@@ -3787,7 +3787,7 @@
}
}
/* Zero plus something non-zero : just return the something */
- return make_float64(float64_val(c) ^ ((uint64_t)signflip << 63));
+ return packFloat64(cSign ^ signflip, cExp, cSig);
}
if (aExp == 0) {