Use standard union for Div Mod (#693)

* Cleanup ui.c div and mod

* Cleanup divRem in pauseMenu.c

* Add non matchings

* Consistent defines

* Restore comment

Author: KEKW555

src/menu/pauseMenu.c

@@ -1232,26 +1232,14 @@ bool32 sub_080A5F24(void) {
     return result;
 }
 
-typedef union {
-    struct {
-        s32 v1;
-        s32 v2;
-    } values;
-    u64 raw;
-} DoubleReturnValue;
-
 void sub_080A5F48(Item item, u32 offset) {
-    // this funcitons signature allows the div function to return a u64 (2x 32 bit registers)
-    // with the result in one register and the remainder in the other
-    typedef u64 DivRem(u32, u32);
-
     s32 ammoCount;
     s32 onesDigit;
     s32 tensDigit;
     void* dest;
     u16* temp2;
     u32 index;
-    DoubleReturnValue ret;
+    union SplitDWord divRem;
 
     switch (item) {
         case ITEM_BOTTLE1:
@@ -1281,9 +1269,9 @@ void sub_080A5F48(Item item, u32 offset) {
     if (ammoCount < 0)
         return;
 
-    ret.raw = ((DivRem*)Div)(ammoCount, 10); // by casting to DivRem, we can recover the remainder from the Div call
-    onesDigit = ret.values.v2;
-    tensDigit = ret.values.v1;
+    divRem = DivAndMod(ammoCount, 10);
+    onesDigit = divRem.HALF.HI;
+    tensDigit = divRem.HALF.LO;
 
     if (tensDigit >= 10)
         tensDigit = 9;

src/ui.c

@@ -113,18 +113,26 @@ void sub_0801C25C(void) {
     }
 }
 
-void sub_0801C2F0(u32 param_1, u32 param_2) {
-    u32 uVar1;
-    register u32 rem asm("r1");
-    param_1 = param_1 * 0x20 + 0x6010000;
+void sub_0801C2F0(u32 dest, u32 param_2) {
+    u32 tensDigit;
+#ifdef NON_MATCHING
+    u32 onesDigit;
+    union SplitDWord divRem;
+#else
+    FORCE_REGISTER(u32 onesDigit, r1);
+    FORCE_REGISTER(union SplitDWord divRem, r0);
+#endif
 
-    uVar1 = Div(param_2, 10);
-    if (uVar1 > 9) {
-        uVar1 = 9;
-    }
+    dest = dest * 0x20 + 0x6010000;
+    divRem = DivAndMod(param_2, 10);
+    onesDigit = divRem.HALF_U.HI;
+    tensDigit = divRem.HALF_U.LO;
+
+    if (tensDigit >= 10)
+        tensDigit = 9;
 
-    DmaCopy32(3, (gUnk_085C4620 + uVar1 * 8), param_1, 0x8 * 4);
-    DmaCopy32(3, (gUnk_085C4620 + (rem + 10) * 8), param_1 + 0x20, 0x8 * 4);
+    DmaCopy32(3, gUnk_085C4620 + tensDigit * 0x8, dest, 0x8 * 4);
+    DmaCopy32(3, gUnk_085C4620 + (onesDigit + 10) * 0x8, dest + 0x20, 0x8 * 4);
 }
 
 void DrawUI(void) {
@@ -277,7 +285,11 @@ void RenderDigits(u32 iconVramIndex, u32 count, u32 isTextYellow, u32 digits) {
     u32 digit;
     vu32* ptr;
     vu32* ptr2;
-    register u32 r1 asm("r1");
+#ifdef NON_MATCHING
+    union SplitDWord divRem;
+#else
+    FORCE_REGISTER(union SplitDWord divRem, r0);
+#endif
 
     puVar4 = RupeeKeyDigits;
     if (isTextYellow == 0) {
@@ -287,13 +299,15 @@ void RenderDigits(u32 iconVramIndex, u32 count, u32 isTextYellow, u32 digits) {
     iVar2 = iVar3 + 0x600c000;
     switch (digits) {
         case 3:
-            digit = Div(count, 100);
-            count = r1;
+            divRem = DivAndMod(count, 100);
+            digit = divRem.HALF_U.LO;
+            count = divRem.HALF_U.HI;
             DmaCopy32(3, puVar4 + digit * 0x40, iVar2, 0x10 * 4);
             iVar2 += 0x40;
         case 2:
-            digit = Div(count, 10);
-            count = r1;
+            divRem = DivAndMod(count, 10);
+            digit = divRem.HALF_U.LO;
+            count = divRem.HALF_U.HI;
             DmaCopy32(3, puVar4 + digit * 0x40, iVar2, 0x10 * 4);
             iVar2 += 0x40;
     }
@@ -440,21 +454,14 @@ void EraseChargeBar(void) {
     }
 }
 
-typedef union {
-    u32 values[2];
-    u64 raw;
-} returnValues;
-
-typedef u64 DivRem(u32, u32);
-
 void DrawChargeBar(void) {
     bool32 tmp1;
     u16* BufferPos;
-    returnValues ret;
     // these names are almost certainly inaccurate
     u32 chargeTime;
     u32 chargeState;
     u32 chargeFrame;
+    union SplitDWord divRem;
 
     tmp1 = FALSE;
     if (!(gHUD.hideFlags & HUD_HIDE_CHARGE_BAR))
@@ -476,10 +483,9 @@ void DrawChargeBar(void) {
         gHUD.unk_6 = 1;
         gHUD.unk_7 = chargeTime;
 
-        // this calls Div and returns the result in ret.values[0] and the remainder in ret.values[1]
-        ret.raw = ((DivRem*)&Div)(chargeTime, 4);
-        chargeState = ret.values[0];
-        chargeFrame = ret.values[1];
+        divRem = DivAndMod(chargeTime, 4);
+        chargeState = divRem.HALF_U.LO;
+        chargeFrame = divRem.HALF_U.HI;
 
         BufferPos[0] = 0xf016;
         BufferPos[11] = 0xf416;