Fix move animation crashing on some emulators because of division by …

…zero (rh-hideout#4121)

* fix flip turn div by zero

* fix incinerate move anim div by zero

include/global.h

@@ -61,7 +61,7 @@
 // Used in cases where division by 0 can occur in the retail version.
 // Avoids invalid opcodes on some emulators, and the otherwise UB.
 #ifdef UBFIX
-#define SAFE_DIV(a, b) ((b) ? (a) / (b) : 0)
+#define SAFE_DIV(a, b) (((b) != 0) ? (a) / (b) : 0)
 #else
 #define SAFE_DIV(a, b) ((a) / (b))
 #endif

src/battle_anim_ghost.c

@@ -474,8 +474,8 @@ void AnimShadowBall(struct Sprite *sprite)
     sprite->data[3] = gBattleAnimArgs[2];
     sprite->data[4] = sprite->x << 4;
     sprite->data[5] = sprite->y << 4;
-    sprite->data[6] = ((oldPosX - sprite->x) << 4) / (gBattleAnimArgs[0] << 1);
-    sprite->data[7] = ((oldPosY - sprite->y) << 4) / (gBattleAnimArgs[0] << 1);
+    sprite->data[6] = SAFE_DIV(((oldPosX - sprite->x) << 4), (gBattleAnimArgs[0] << 1));
+    sprite->data[7] = SAFE_DIV(((oldPosY - sprite->y) << 4), (gBattleAnimArgs[0] << 1));
     sprite->callback = AnimShadowBall_Step;
 }
 

src/battle_anim_mons.c

@@ -1025,8 +1025,8 @@ void InitSpriteDataForLinearTranslation(struct Sprite *sprite)
 {
     s16 x = (sprite->data[2] - sprite->data[1]) << 8;
     s16 y = (sprite->data[4] - sprite->data[3]) << 8;
-    sprite->data[1] = x / sprite->data[0];
-    sprite->data[2] = y / sprite->data[0];
+    sprite->data[1] = SAFE_DIV(x, sprite->data[0]);
+    sprite->data[2] = SAFE_DIV(y, sprite->data[0]);
     sprite->data[4] = 0;
     sprite->data[3] = 0;
 }