Changed _ultof rounding behaviour to ties away from zero to match _ltof

Author: ZERICO2005

src/crt/ultof.src

@@ -4,6 +4,8 @@
 
 	public	__ultof
 
+if 0
+
 ; round to nearest ties to even
 __ultof:
 	bit	7, a
@@ -26,4 +28,27 @@ __ultof:
 	res	0, c
 	ret
 
+else
+
+; round to nearest ties away from zero (to match __ltof behaviour)
+__ultof:
+	bit	7, a
+	jp	z, __ltof	; common case
+	; A:UBC > INT32_MAX
+	res	7, a	; sets the LSB of the exponent
+	; A:UBC >>= 8
+	push	af
+	or	a, c	; M = Round
+	inc	sp
+	push	bc
+	inc	sp
+	pop	bc
+	inc	sp
+	ld	a, $4F	; sets the exponent
+	ret	p	; round down
+	inc	bc
+	ret	; round up (this will not overflow because bit 23 is 0)
+
+end if
+
 	extern	__ltof

test/floating_point/ultof/src/main.c

@@ -37,13 +37,23 @@ size_t run_test(void) {
         result.flt = (float)input[i];
         if (result.bin != output[i].bin) {
             // ignore round to maximum magnitude errors from __ltof
-            bool ignore_ltof_failure =
-                (input[i] <= INT32_MAX) &&
-                (result.bin == output[i].bin + 1);
-            if (ignore_ltof_failure == false) {
-                print_failed(input[i], result.bin, output[i].bin);
-                return i;
-            }
+            #if 0
+                bool ignore_ltof_failure =
+                    (input[i] <= INT32_MAX) &&
+                    (result.bin == output[i].bin + 1);
+                if (ignore_ltof_failure == false) {
+                    print_failed(input[i], result.bin, output[i].bin);
+                    return i;
+                }
+            #else
+                // round to nearest ties away from zero to match __ltof behaviour
+                bool ignore_ltof_failure =
+                    (result.bin == output[i].bin + 1);
+                if (ignore_ltof_failure == false) {
+                    print_failed(input[i], result.bin, output[i].bin);
+                    return i;
+                }
+            #endif
         }
     }