[for-10.0,05/25] target/arm: Set FloatInfZeroNaNRule explicitly

Commit Message

Peter Maydell Nov. 28, 2024, 10:42 a.m. UTC

Set the FloatInfZeroNaNRule explicitly for the Arm target,
so we can remove the ifdef from pickNaNMulAdd().

Signed-off-by: Peter Maydell <[e-mail]>
---
 target/arm/cpu.c               | 3 +++
 fpu/softfloat-specialize.c.inc | 8 +-------
 2 files changed, 4 insertions(+), 7 deletions(-)

Patch

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 6938161b954..ead39793985 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -173,11 +173,14 @@  void arm_register_el_change_hook(ARMCPU *cpu, ARMELChangeHookFn *hook,
  *  * tininess-before-rounding
  *  * 2-input NaN propagation prefers SNaN over QNaN, and then
  *    operand A over operand B (see FPProcessNaNs() pseudocode)
+ *  * 0 * Inf + NaN returns the default NaN if the input NaN is quiet,
+ *    and the input NaN if it is signalling
  */
 static void arm_set_default_fp_behaviours(float_status *s)
 {
     set_float_detect_tininess(float_tininess_before_rounding, s);
     set_float_2nan_prop_rule(float_2nan_prop_s_ab, s);
+    set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, s);
 }
 
 static void cp_reg_reset(gpointer key, gpointer value, gpointer opaque)
diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc
index f5b422e07b5..b3ffa54f368 100644
--- a/fpu/softfloat-specialize.c.inc
+++ b/fpu/softfloat-specialize.c.inc
@@ -489,13 +489,7 @@  static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls,
         /*
          * Temporarily fall back to ifdef ladder
          */
-#if defined(TARGET_ARM)
-        /*
-         * For ARM, the (inf,zero,qnan) case returns the default NaN,
-         * but (inf,zero,snan) returns the input NaN.
-         */
-        rule = float_infzeronan_dnan_if_qnan;
-#elif defined(TARGET_MIPS)
+#if defined(TARGET_MIPS)
         if (snan_bit_is_one(status)) {
             /*
              * For MIPS systems that conform to IEEE754-1985, the (inf,zero,nan)