softfloat: implement fused multiply-add NaN propagation for MIPS
Add a pickNaNMulAdd function for MIPS, implementing NaN propagation
rules for MIPS fused multiply-add instructions.
Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
diff --git a/fpu/softfloat-specialize.h b/fpu/softfloat-specialize.h
index a1d489e..518f694 100644
--- a/fpu/softfloat-specialize.h
+++ b/fpu/softfloat-specialize.h
@@ -486,6 +486,33 @@
return 1;
}
}
+#elif defined(TARGET_MIPS)
+static int pickNaNMulAdd(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
+ flag cIsQNaN, flag cIsSNaN, flag infzero STATUS_PARAM)
+{
+ /* For MIPS, the (inf,zero,qnan) case sets InvalidOp and returns
+ * the default NaN
+ */
+ if (infzero) {
+ float_raise(float_flag_invalid STATUS_VAR);
+ return 3;
+ }
+
+ /* Prefer sNaN over qNaN, in the a, b, c order. */
+ if (aIsSNaN) {
+ return 0;
+ } else if (bIsSNaN) {
+ return 1;
+ } else if (cIsSNaN) {
+ return 2;
+ } else if (aIsQNaN) {
+ return 0;
+ } else if (bIsQNaN) {
+ return 1;
+ } else {
+ return 2;
+ }
+}
#elif defined(TARGET_PPC)
static int pickNaNMulAdd(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
flag cIsQNaN, flag cIsSNaN, flag infzero STATUS_PARAM)
