target/hexagon: Use float32_muladd_scalbn for helper_sffma_sc

This instruction has a special case that 0 * x + c returns c
without the normal sign folding that comes with 0 + -0.
Use the new float_muladd_suppress_add_product_zero to
describe this.

Reviewed-by: Brian Cain <brian.cain@oss.qualcomm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

diff --git a/target/hexagon/op_helper.c b/target/hexagon/op_helper.c
index 95bfa5d0299b4b5726b9c942d6cf13f531435489..53c65e852eca26a74a91d91a8b0453a5e876032d 100644 (file)
--- a/target/hexagon/op_helper.c
+++ b/target/hexagon/op_helper.c
@@ -1080,15 +1080,10 @@ static float32 check_nan(float32 dst, float32 x, float_status *fp_status)
 float32 HELPER(sffma_sc)(CPUHexagonState *env, float32 RxV,
                          float32 RsV, float32 RtV, float32 PuV)
 {
-    size4s_t tmp;
     arch_fpop_start(env);
-    RxV = check_nan(RxV, RxV, &env->fp_status);
-    RxV = check_nan(RxV, RsV, &env->fp_status);
-    RxV = check_nan(RxV, RtV, &env->fp_status);
-    tmp = internal_fmafx(RsV, RtV, RxV, fSXTN(8, 64, PuV), &env->fp_status);
-    if (!(float32_is_zero(RxV) && is_zero_prod(RsV, RtV))) {
-        RxV = tmp;
-    }
+    RxV = float32_muladd_scalbn(RsV, RtV, RxV, fSXTN(8, 64, PuV),
+                                float_muladd_suppress_add_product_zero,
+                                &env->fp_status);
     arch_fpop_end(env);
     return RxV;
 }