target/arm: Use float_round_to_odd in helper_fcvtx_f64_to_f32

Softfloat has native support for round-to-odd.  Use it.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241206031428.78634-1-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/tcg/helper-a64.c b/target/arm/tcg/helper-a64.c
index 28de7468cd1ff3ea9a3eccaf006b322da7e22461..fb6fe0fcaa902158d5a8714017ea7116a0c6e572 100644 (file)
--- a/target/arm/tcg/helper-a64.c
+++ b/target/arm/tcg/helper-a64.c
@@ -408,23 +408,13 @@ float64 HELPER(frecpx_f64)(float64 a, void *fpstp)
 
 float32 HELPER(fcvtx_f64_to_f32)(float64 a, CPUARMState *env)
 {
-    /* Von Neumann rounding is implemented by using round-to-zero
-     * and then setting the LSB of the result if Inexact was raised.
-     */
     float32 r;
     float_status *fpst = &env->vfp.fp_status;
-    float_status tstat = *fpst;
-    int exflags;
-
-    set_float_rounding_mode(float_round_to_zero, &tstat);
-    set_float_exception_flags(0, &tstat);
-    r = float64_to_float32(a, &tstat);
-    exflags = get_float_exception_flags(&tstat);
-    if (exflags & float_flag_inexact) {
-        r = make_float32(float32_val(r) | 1);
-    }
-    exflags |= get_float_exception_flags(fpst);
-    set_float_exception_flags(exflags, fpst);
+    int old = get_float_rounding_mode(fpst);
+
+    set_float_rounding_mode(float_round_to_odd, fpst);
+    r = float64_to_float32(a, fpst);
+    set_float_rounding_mode(old, fpst);
     return r;
 }