reversed botched attempt to increase FP division precission

c64/basic/math/div_FAC1_denorm.s

@@ -3,17 +3,21 @@
 // #LAYOUT# *   *       #IGNORE
 
 //
-// Math package - denormalize FAC1 mantissa and adapt its exponent accordingly,
-// so that division is more precise
+// Math package - denormalize FAC1 mantissa and adapt its exponent accordingly
 //
 
 // XXX test this
 
 div_FAC1_denorm:
 
+	// Set FACOV to 0, no need for increased precision here
+
+	lda #$00
+	sta FACOV
+
 	// Start by moving whole bytes, if possible
 
-	lda FACOV
+	lda FAC1_mantissa+3
 	bne div_FAC1_denorm_by_bit         // branch if last byte of mantissa is non-zero
 
 	lda FAC1_exponent
@@ -27,8 +31,6 @@ div_FAC1_denorm:
 
 	// Move mantissa bytes
 
-	lda FAC1_mantissa+3
-	sta FACOV
 	lda FAC1_mantissa+2
 	sta FAC1_mantissa+3
 	lda FAC1_mantissa+1
@@ -42,7 +44,7 @@ div_FAC1_denorm:
 
 div_FAC1_denorm_by_bit:
 
-	lda FACOV
+	lda FAC1_mantissa+3
 	and #$01
 	bne div_FAC1_denorm_done           // branch if lowest bit of mantissa is already 1
 
@@ -61,7 +63,6 @@ div_FAC1_denorm_by_bit:
 	ror FAC1_mantissa+1
 	ror FAC1_mantissa+2
 	ror FAC1_mantissa+3
-	ror FACOV
 
 	bcc div_FAC1_denorm_by_bit         // branch always