# HG changeset patch
# User William Astle <lost@l-w.ca>
# Date 1694397947 21600
# Node ID 718f9b7381b39d389c8499c8df8355db5946830f
# Parent  ba559f231929cf1041cabcdcecf4913f17f78231
Slight improvements to some floating point code

diff -r ba559f231929 -r 718f9b7381b3 src/number.s
--- a/src/number.s	Thu Aug 10 00:24:52 2023 -0600
+++ b/src/number.s	Sun Sep 10 20:05:47 2023 -0600
@@ -109,9 +109,7 @@
                 pshs b                          ; apply exponent counter to exponent
                 lda val.fpexp,x
                 suba ,s+
-                bls fp_normalize6               ; brif we underflowed to zero
-                bcc fp_normalize3               ; brif we did not overflow
-OVERROR2        jmp OVERROR                     ; raise overflow
+                bls fp_normalize6               ; brif we underflowed to zero; overflow is impossible
 fp_normalize3   lsl ,s+                         ; set C if the high bit of extra precision is set
                 bcs fp_normalize5               ; brif bit set - we have to do rounding
 fp_normalize4   rts                             ; return if no rounding
@@ -125,8 +123,8 @@
                 bne fp_normalize4               ; brif high word doesn't carry
                 ror val.fpmant,x                ; shift right C in to high bit of mantissa (already set to get here)
                 inc val.fpexp,x                 ; bump exponent for a right shift
-                beq OVERROR2                    ; brif it overflows (> +127)
-                rts                             ; return result (only possible result was mantissa wrapped to zero)
+                bne fp_normalize4               ; brif it doesn't overflow (> +127)
+OVERROR2        jmp OVERROR                     ; raise overflow
 fp_normalize6   clr val.fpmant,x                ; clear mantissa
                 clr val.fpmant+1,x
                 clr val.fpmant+2,x
@@ -150,7 +148,7 @@
                 adcb val.int+1,u
                 adca val.int,u
                 std val.int,y
-                lbvs OVERROR                    ; brif calculation overflowed
+                bvs OVERROR2                    ; brif calculation overflowed
                 rts
 val_sub         ldb val.type,x                  ; get type of left operand
                 stb val.type,y                  ; set result type
@@ -163,7 +161,7 @@
                 sbcb val.int+1,u
                 sbca val.int,u
                 std val.int,y
-                lbvs OVERROR                    ; brif overflow
+                bvs OVERROR2                    ; brif overflow
                 rts
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ; FP subtraction: just invert the sign of the second operand and add; operands must be writable and they should be