decompile util.s

8 files changed, 532 insertions, 481 deletions

diff --git a/asm/util.s b/asm/util.s
deleted file mode 100644
index 73342f136..000000000
--- a/asm/util.s
+++ /dev/null
@@ -1,466 +0,0 @@
-	.include "asm/macros.inc"
-	.include "constants/constants.inc"
-
-	.syntax unified
-
-	.text
-
-	thumb_func_start CreateInvisibleSpriteWithCallback
-CreateInvisibleSpriteWithCallback: @ 806F640
-	push {r4-r6,lr}
-	adds r6, r0, 0
-	ldr r0, =gUnknown_0832A3A8
-	movs r1, 0xF8
-	movs r2, 0xA8
-	movs r3, 0xE
-	bl CreateSprite
-	lsls r0, 24
-	lsrs r0, 24
-	ldr r5, =gSprites
-	lsls r2, r0, 4
-	adds r2, r0
-	lsls r2, 2
-	adds r3, r2, r5
-	adds r3, 0x3E
-	ldrb r1, [r3]
-	movs r4, 0x4
-	orrs r1, r4
-	strb r1, [r3]
-	adds r5, 0x1C
-	adds r2, r5
-	str r6, [r2]
-	pop {r4-r6}
-	pop {r1}
-	bx r1
-	.pool
-	thumb_func_end CreateInvisibleSpriteWithCallback
-
-	thumb_func_start StoreWordInTwoHalfwords
-StoreWordInTwoHalfwords: @ 806F67C
-	strh r1, [r0]
-	lsrs r1, 16
-	strh r1, [r0, 0x2]
-	bx lr
-	thumb_func_end StoreWordInTwoHalfwords
-
-	thumb_func_start LoadWordFromTwoHalfwords
-LoadWordFromTwoHalfwords: @ 806F684
-	ldrh r2, [r0]
-	movs r3, 0x2
-	ldrsh r0, [r0, r3]
-	lsls r0, 16
-	orrs r2, r0
-	str r2, [r1]
-	bx lr
-	thumb_func_end LoadWordFromTwoHalfwords
-
-	thumb_func_start SetBgAffineStruct
-SetBgAffineStruct: @ 806F694
-	push {r4-r7,lr}
-	mov r7, r8
-	push {r7}
-	ldr r4, [sp, 0x18]
-	ldr r5, [sp, 0x1C]
-	ldr r6, [sp, 0x20]
-	ldr r7, [sp, 0x24]
-	mov r8, r7
-	str r1, [r0]
-	str r2, [r0, 0x4]
-	strh r3, [r0, 0x8]
-	strh r4, [r0, 0xA]
-	strh r5, [r0, 0xC]
-	strh r6, [r0, 0xE]
-	mov r1, r8
-	strh r1, [r0, 0x10]
-	pop {r3}
-	mov r8, r3
-	pop {r4-r7}
-	pop {r0}
-	bx r0
-	thumb_func_end SetBgAffineStruct
-
-	thumb_func_start DoBgAffineSet
-DoBgAffineSet: @ 806F6C0
-	push {r4-r6,lr}
-	mov r6, r8
-	push {r6}
-	sub sp, 0x24
-	mov r8, r0
-	ldr r0, [sp, 0x38]
-	ldr r4, [sp, 0x3C]
-	ldr r5, [sp, 0x40]
-	ldr r6, [sp, 0x44]
-	lsls r6, 16
-	lsrs r6, 16
-	lsls r3, 16
-	asrs r3, 16
-	lsls r0, 16
-	asrs r0, 16
-	str r0, [sp]
-	lsls r4, 16
-	asrs r4, 16
-	str r4, [sp, 0x4]
-	lsls r5, 16
-	asrs r5, 16
-	str r5, [sp, 0x8]
-	str r6, [sp, 0xC]
-	add r0, sp, 0x10
-	bl SetBgAffineStruct
-	add r0, sp, 0x10
-	mov r1, r8
-	movs r2, 0x1
-	bl BgAffineSet
-	add sp, 0x24
-	pop {r3}
-	mov r8, r3
-	pop {r4-r6}
-	pop {r0}
-	bx r0
-	thumb_func_end DoBgAffineSet
-
-	thumb_func_start CopySpriteTiles
-CopySpriteTiles: @ 806F70C
-	push {r4-r7,lr}
-	mov r7, r10
-	mov r6, r9
-	mov r5, r8
-	push {r5-r7}
-	sub sp, 0x38
-	str r2, [sp, 0x20]
-	adds r4, r3, 0
-	ldr r7, [sp, 0x58]
-	lsls r0, 24
-	lsls r1, 24
-	ldr r2, =gUnknown_0832A3C0
-	lsrs r1, 23
-	lsrs r0, 21
-	adds r1, r0
-	adds r0, r2, 0x1
-	adds r0, r1, r0
-	ldrb r0, [r0]
-	str r0, [sp, 0x24]
-	adds r1, r2
-	ldrb r1, [r1]
-	str r1, [sp, 0x28]
-	movs r0, 0
-	b _0806F88C
-	.pool
-_0806F740:
-	movs r5, 0
-	adds r0, 0x1
-	str r0, [sp, 0x30]
-	b _0806F874
-_0806F748:
-	ldrh r0, [r4]
-	ldr r2, =0x000003ff
-	adds r1, r2, 0
-	ands r1, r0
-	lsls r1, 5
-	mov r8, r1
-	movs r2, 0xC0
-	lsls r2, 4
-	adds r1, r2, 0
-	ands r1, r0
-	mov r2, sp
-	strh r0, [r2, 0x34]
-	cmp r1, 0
-	bne _0806F788
-	ldr r0, [sp, 0x20]
-	add r0, r8
-	adds r1, r7, 0
-	ldr r2, =0x04000008
-	bl CpuSet
-	adds r4, 0x2
-	str r4, [sp, 0x2C]
-	adds r7, 0x20
-	mov r10, r7
-	adds r5, 0x1
-	mov r9, r5
-	b _0806F86A
-	.pool
-_0806F788:
-	movs r0, 0x80
-	lsls r0, 4
-	cmp r1, r0
-	bne _0806F7CC
-	movs r1, 0
-	adds r4, 0x2
-	str r4, [sp, 0x2C]
-	movs r2, 0x20
-	adds r2, r7
-	mov r10, r2
-	adds r5, 0x1
-	mov r9, r5
-_0806F7A0:
-	lsls r4, r1, 24
-	asrs r4, 24
-	movs r0, 0x7
-	subs r0, r4
-	lsls r0, 2
-	add r0, r8
-	ldr r1, [sp, 0x20]
-	adds r0, r1, r0
-	lsls r1, r4, 2
-	adds r1, r7, r1
-	ldr r2, =0x04000001
-	bl CpuSet
-	adds r4, 0x1
-	lsls r4, 24
-	lsrs r1, r4, 24
-	asrs r4, 24
-	cmp r4, 0x7
-	ble _0806F7A0
-	b _0806F86A
-	.pool
-_0806F7CC:
-	movs r1, 0
-	adds r4, 0x2
-	str r4, [sp, 0x2C]
-	movs r2, 0x20
-	adds r2, r7
-	mov r10, r2
-	adds r5, 0x1
-	mov r9, r5
-	movs r0, 0xF
-	mov r12, r0
-_0806F7E0:
-	movs r2, 0
-	lsls r4, r1, 24
-	lsls r0, r4, 2
-	lsrs r0, 24
-	adds r6, r0, 0x3
-	mov r1, r8
-	adds r5, r1, r0
-_0806F7EE:
-	lsls r1, r2, 24
-	asrs r1, 24
-	subs r0, r6, r1
-	mov r2, sp
-	adds r3, r2, r0
-	adds r0, r5, r1
-	ldr r2, [sp, 0x20]
-	adds r0, r2, r0
-	ldrb r2, [r0]
-	mov r0, r12
-	ands r0, r2
-	lsls r0, 4
-	lsrs r2, 4
-	orrs r0, r2
-	strb r0, [r3]
-	adds r1, 0x1
-	lsls r1, 24
-	lsrs r2, r1, 24
-	asrs r1, 24
-	cmp r1, 0x3
-	ble _0806F7EE
-	movs r1, 0x80
-	lsls r1, 17
-	adds r0, r4, r1
-	lsrs r1, r0, 24
-	asrs r0, 24
-	cmp r0, 0x7
-	ble _0806F7E0
-	mov r2, sp
-	ldrh r0, [r2, 0x34]
-	movs r2, 0x80
-	lsls r2, 4
-	ands r0, r2
-	cmp r0, 0
-	beq _0806F860
-	movs r1, 0
-_0806F836:
-	lsls r4, r1, 24
-	asrs r4, 24
-	movs r0, 0x7
-	subs r0, r4
-	lsls r0, 2
-	add r0, sp
-	lsls r1, r4, 2
-	adds r1, r7, r1
-	ldr r2, =0x04000001
-	bl CpuSet
-	adds r4, 0x1
-	lsls r4, 24
-	lsrs r1, r4, 24
-	asrs r4, 24
-	cmp r4, 0x7
-	ble _0806F836
-	b _0806F86A
-	.pool
-_0806F860:
-	mov r0, sp
-	adds r1, r7, 0
-	ldr r2, =0x04000008
-	bl CpuSet
-_0806F86A:
-	ldr r4, [sp, 0x2C]
-	mov r7, r10
-	mov r1, r9
-	lsls r0, r1, 24
-	lsrs r5, r0, 24
-_0806F874:
-	ldr r2, [sp, 0x28]
-	cmp r5, r2
-	bcs _0806F87C
-	b _0806F748
-_0806F87C:
-	movs r0, 0x20
-	ldr r1, [sp, 0x28]
-	subs r0, r1
-	lsls r0, 1
-	adds r4, r0
-	ldr r2, [sp, 0x30]
-	lsls r0, r2, 24
-	lsrs r0, 24
-_0806F88C:
-	ldr r1, [sp, 0x24]
-	cmp r0, r1
-	bcs _0806F894
-	b _0806F740
-_0806F894:
-	add sp, 0x38
-	pop {r3-r5}
-	mov r8, r3
-	mov r9, r4
-	mov r10, r5
-	pop {r4-r7}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end CopySpriteTiles
-
-	thumb_func_start CountTrailingZeroBits
-CountTrailingZeroBits: @ 806F8A8
-	push {lr}
-	adds r2, r0, 0
-	movs r1, 0
-	movs r3, 0x1
-_0806F8B0:
-	adds r0, r2, 0
-	ands r0, r3
-	cmp r0, 0
-	beq _0806F8BC
-	adds r0, r1, 0
-	b _0806F8CA
-_0806F8BC:
-	lsrs r2, 1
-	adds r0, r1, 0x1
-	lsls r0, 24
-	lsrs r1, r0, 24
-	cmp r1, 0x1F
-	bls _0806F8B0
-	movs r0, 0
-_0806F8CA:
-	pop {r1}
-	bx r1
-	thumb_func_end CountTrailingZeroBits
-
-	thumb_func_start CalcCRC16
-CalcCRC16: @ 806F8D0
-	push {r4-r7,lr}
-	adds r7, r0, 0
-	adds r4, r1, 0
-	ldr r2, =0x00001121
-	movs r3, 0
-	cmp r3, r4
-	bge _0806F91C
-	movs r6, 0x1
-	ldr r0, =0x00008408
-	adds r5, r0, 0
-_0806F8E4:
-	adds r0, r7, r3
-	ldrb r0, [r0]
-	eors r2, r0
-	movs r1, 0
-	adds r3, 0x1
-_0806F8EE:
-	adds r0, r2, 0
-	ands r0, r6
-	cmp r0, 0
-	beq _0806F908
-	lsrs r0, r2, 1
-	eors r0, r5
-	lsls r0, 16
-	lsrs r2, r0, 16
-	b _0806F90A
-	.pool
-_0806F908:
-	lsrs r2, 1
-_0806F90A:
-	adds r0, r1, 0x1
-	lsls r0, 16
-	lsrs r1, r0, 16
-	cmp r1, 0x7
-	bls _0806F8EE
-	lsls r0, r3, 16
-	lsrs r3, r0, 16
-	cmp r3, r4
-	blt _0806F8E4
-_0806F91C:
-	mvns r0, r2
-	lsls r0, 16
-	lsrs r0, 16
-	pop {r4-r7}
-	pop {r1}
-	bx r1
-	thumb_func_end CalcCRC16
-
-	thumb_func_start CalcCRC16WithTable
-CalcCRC16WithTable: @ 806F928
-	push {r4-r6,lr}
-	adds r5, r0, 0
-	adds r4, r1, 0
-	ldr r2, =0x00001121
-	movs r3, 0
-	cmp r3, r4
-	bcs _0806F956
-	ldr r6, =gUnknown_0832A3D8
-_0806F938:
-	lsrs r1, r2, 8
-	adds r0, r5, r3
-	ldrb r0, [r0]
-	eors r2, r0
-	lsls r0, r2, 24
-	lsrs r0, 23
-	adds r0, r6
-	ldrh r0, [r0]
-	adds r2, r0, 0
-	eors r2, r1
-	adds r0, r3, 0x1
-	lsls r0, 16
-	lsrs r3, r0, 16
-	cmp r3, r4
-	bcc _0806F938
-_0806F956:
-	mvns r0, r2
-	lsls r0, 16
-	lsrs r0, 16
-	pop {r4-r6}
-	pop {r1}
-	bx r1
-	.pool
-	thumb_func_end CalcCRC16WithTable
-
-	thumb_func_start CalcByteArraySum
-CalcByteArraySum: @ 806F96C
-	push {r4,lr}
-	adds r4, r0, 0
-	movs r3, 0
-	movs r2, 0
-	cmp r3, r1
-	bcs _0806F984
-_0806F978:
-	adds r0, r4, r2
-	ldrb r0, [r0]
-	adds r3, r0
-	adds r2, 0x1
-	cmp r2, r1
-	bcc _0806F978
-_0806F984:
-	adds r0, r3, 0
-	pop {r4}
-	pop {r1}
-	bx r1
-	thumb_func_end CalcByteArraySum
-
-	.align 2, 0 @ Don't pad with nop.
diff --git a/data/data3.s b/data/data3.s
index dac15b02e..ee981ac4f 100644
--- a/data/data3.s
+++ b/data/data3.s
@@ -5,17 +5,7 @@
 
 	.section .rodata
 
-gBitTable:: @ 832A328
-	.incbin "baserom.gba", 0x32a328, 0x80
 
-gUnknown_0832A3A8:: @ 832A3A8
-	.incbin "baserom.gba", 0x32a3a8, 0x18
-
-gUnknown_0832A3C0:: @ 832A3C0
-	.incbin "baserom.gba", 0x32a3c0, 0x18
-
-gUnknown_0832A3D8:: @ 832A3D8
-	.incbin "baserom.gba", 0x32a3d8, 0xa00
 
 @ 832ADD8
 	.include "data/egg_moves.inc"
diff --git a/graphics/interface/blank.pal b/graphics/interface/blank.pal
new file mode 100644
index 000000000..9757f2e57
--- /dev/null
+++ b/graphics/interface/blank.pal
@@ -0,0 +1,19 @@
+JASC-PAL
+0100
+16
+0 0 0
+255 255 255
+189 189 197
+131 131 139
+98 98 123
+65 74 106
+41 49 90
+148 255 164
+139 246 115
+65 205 57
+0 0 0
+0 0 0
+0 0 0
+0 0 0
+213 213 205
+74 74 74
diff --git a/graphics/interface/blank.png b/graphics/interface/blank.png
new file mode 100644
index 000000000..3a4ba289c
--- /dev/null
+++ b/graphics/interface/blank.png
diff --git a/include/sprite.h b/include/sprite.h
index 68474b2ae..7b3c9fb5a 100644
--- a/include/sprite.h
+++ b/include/sprite.h
@@ -237,9 +237,11 @@ struct OamMatrix
     s16 d;
 };
 
-extern struct Sprite gSprites[];
-
 extern const struct OamData gDummyOamData;
+extern const union AnimCmd *const gDummySpriteAnimTable[];
+extern const union AffineAnimCmd *const gDummySpriteAffineAnimTable[];
+
+extern struct Sprite gSprites[];
 
 void ResetSpriteData(void);
 void AnimateSprites(void);
diff --git a/include/util.h b/include/util.h
index 69ef329ad..63887b13f 100644
--- a/include/util.h
+++ b/include/util.h
@@ -3,13 +3,15 @@
 
 #include "sprite.h"
 
-extern const u8 gMiscBlank_Gfx[];
+extern const u8 gMiscBlank_Gfx[]; // unused in Emerald
 extern const u32 gBitTable[];
 
 u8 CreateInvisibleSpriteWithCallback(void (*)(struct Sprite *));
 void StoreWordInTwoHalfwords(u16 *, u32);
 void LoadWordFromTwoHalfwords(u16 *, u32 *);
+int CountTrailingZeroBits(u32 value);
 u16 CalcCRC16(u8 *data, s32 length);
-u16 CalcCRC16WithTable(u8 *data, s32 length);
+u16 CalcCRC16WithTable(u8 *data, u32 length);
+u32 CalcByteArraySum(const u8* data, u32 length);
 
 #endif // GUARD_UTIL_H
diff --git a/ld_script.txt b/ld_script.txt
index d558dddff..4a5bb643a 100644
--- a/ld_script.txt
+++ b/ld_script.txt
@@ -76,7 +76,7 @@ SECTIONS {
         asm/pokemon_3.o(.text);
         src/trig.o(.text);
         src/rng.o(.text);
-        asm/util.o(.text);
+        src/util.o(.text);
         src/blend_palette.o(.text);
         asm/daycare.o(.text);
         asm/egg_hatch.o(.text);
@@ -303,6 +303,7 @@ SECTIONS {
         data/battle_controller_link_opponent.o(.rodata);
         data/data2c.o(.rodata);
         src/trig.o(.rodata);
+        src/util.o(.rodata);
         data/data3.o(.rodata);
         src/pokemon_size_record.o(.rodata)
         data/data3a.o(.rodata)
diff --git a/src/util.c b/src/util.c
new file mode 100644
index 000000000..27b7c5ee5
--- /dev/null
+++ b/src/util.c
@@ -0,0 +1,503 @@
+#include "global.h"
+#include "util.h"
+#include "sprite.h"
+
+const u32 gBitTable[] =
+{
+    1 << 0,
+    1 << 1,
+    1 << 2,
+    1 << 3,
+    1 << 4,
+    1 << 5,
+    1 << 6,
+    1 << 7,
+    1 << 8,
+    1 << 9,
+    1 << 10,
+    1 << 11,
+    1 << 12,
+    1 << 13,
+    1 << 14,
+    1 << 15,
+    1 << 16,
+    1 << 17,
+    1 << 18,
+    1 << 19,
+    1 << 20,
+    1 << 21,
+    1 << 22,
+    1 << 23,
+    1 << 24,
+    1 << 25,
+    1 << 26,
+    1 << 27,
+    1 << 28,
+    1 << 29,
+    1 << 30,
+    1 << 31,
+};
+
+static const struct SpriteTemplate sInvisibleSpriteTemplate =
+{
+    .tileTag = 0,
+    .paletteTag = 0,
+    .oam = &gDummyOamData,
+    .anims = gDummySpriteAnimTable,
+    .images = NULL,
+    .affineAnims = gDummySpriteAffineAnimTable,
+    .callback = SpriteCallbackDummy,
+};
+
+static const u8 sSpriteDimensions[3][4][2] =
+{
+    // square
+    {
+        {1, 1},
+        {2, 2},
+        {4, 4},
+        {8, 8},
+    },
+
+    // horizontal rectangle
+    {
+        {2, 1},
+        {4, 1},
+        {4, 2},
+        {8, 4},
+    },
+
+    // vertical rectangle
+    {
+        {1, 2},
+        {1, 4},
+        {2, 4},
+        {4, 8},
+    },
+};
+
+static const u16 sCrc16Table[] =
+{
+    0x0000, 0x1189, 0x2312, 0x329B, 0x4624, 0x57AD, 0x6536, 0x74BF,
+    0x8C48, 0x9DC1, 0xAF5A, 0xBED3, 0xCA6C, 0xDBE5, 0xE97E, 0xF8F7,
+    0x1081, 0x0108, 0x3393, 0x221A, 0x56A5, 0x472C, 0x75B7, 0x643E,
+    0x9CC9, 0x8D40, 0xBFDB, 0xAE52, 0xDAED, 0xCB64, 0xF9FF, 0xE876,
+    0x2102, 0x308B, 0x0210, 0x1399, 0x6726, 0x76AF, 0x4434, 0x55BD,
+    0xAD4A, 0xBCC3, 0x8E58, 0x9FD1, 0xEB6E, 0xFAE7, 0xC87C, 0xD9F5,
+    0x3183, 0x200A, 0x1291, 0x0318, 0x77A7, 0x662E, 0x54B5, 0x453C,
+    0xBDCB, 0xAC42, 0x9ED9, 0x8F50, 0xFBEF, 0xEA66, 0xD8FD, 0xC974,
+    0x4204, 0x538D, 0x6116, 0x709F, 0x0420, 0x15A9, 0x2732, 0x36BB,
+    0xCE4C, 0xDFC5, 0xED5E, 0xFCD7, 0x8868, 0x99E1, 0xAB7A, 0xBAF3,
+    0x5285, 0x430C, 0x7197, 0x601E, 0x14A1, 0x0528, 0x37B3, 0x263A,
+    0xDECD, 0xCF44, 0xFDDF, 0xEC56, 0x98E9, 0x8960, 0xBBFB, 0xAA72,
+    0x6306, 0x728F, 0x4014, 0x519D, 0x2522, 0x34AB, 0x0630, 0x17B9,
+    0xEF4E, 0xFEC7, 0xCC5C, 0xDDD5, 0xA96A, 0xB8E3, 0x8A78, 0x9BF1,
+    0x7387, 0x620E, 0x5095, 0x411C, 0x35A3, 0x242A, 0x16B1, 0x0738,
+    0xFFCF, 0xEE46, 0xDCDD, 0xCD54, 0xB9EB, 0xA862, 0x9AF9, 0x8B70,
+    0x8408, 0x9581, 0xA71A, 0xB693, 0xC22C, 0xD3A5, 0xE13E, 0xF0B7,
+    0x0840, 0x19C9, 0x2B52, 0x3ADB, 0x4E64, 0x5FED, 0x6D76, 0x7CFF,
+    0x9489, 0x8500, 0xB79B, 0xA612, 0xD2AD, 0xC324, 0xF1BF, 0xE036,
+    0x18C1, 0x0948, 0x3BD3, 0x2A5A, 0x5EE5, 0x4F6C, 0x7DF7, 0x6C7E,
+    0xA50A, 0xB483, 0x8618, 0x9791, 0xE32E, 0xF2A7, 0xC03C, 0xD1B5,
+    0x2942, 0x38CB, 0x0A50, 0x1BD9, 0x6F66, 0x7EEF, 0x4C74, 0x5DFD,
+    0xB58B, 0xA402, 0x9699, 0x8710, 0xF3AF, 0xE226, 0xD0BD, 0xC134,
+    0x39C3, 0x284A, 0x1AD1, 0x0B58, 0x7FE7, 0x6E6E, 0x5CF5, 0x4D7C,
+    0xC60C, 0xD785, 0xE51E, 0xF497, 0x8028, 0x91A1, 0xA33A, 0xB2B3,
+    0x4A44, 0x5BCD, 0x6956, 0x78DF, 0x0C60, 0x1DE9, 0x2F72, 0x3EFB,
+    0xD68D, 0xC704, 0xF59F, 0xE416, 0x90A9, 0x8120, 0xB3BB, 0xA232,
+    0x5AC5, 0x4B4C, 0x79D7, 0x685E, 0x1CE1, 0x0D68, 0x3FF3, 0x2E7A,
+    0xE70E, 0xF687, 0xC41C, 0xD595, 0xA12A, 0xB0A3, 0x8238, 0x93B1,
+    0x6B46, 0x7ACF, 0x4854, 0x59DD, 0x2D62, 0x3CEB, 0x0E70, 0x1FF9,
+    0xF78F, 0xE606, 0xD49D, 0xC514, 0xB1AB, 0xA022, 0x92B9, 0x8330,
+    0x7BC7, 0x6A4E, 0x58D5, 0x495C, 0x3DE3, 0x2C6A, 0x1EF1, 0x0F78,
+};
+
+const u8 gMiscBlank_Gfx[] = INCBIN_U8("graphics/interface/blank.4bpp"); // unused in Emerald
+
+u8 CreateInvisibleSpriteWithCallback(void (*callback)(struct Sprite *))
+{
+    u8 sprite = CreateSprite(&sInvisibleSpriteTemplate, 248, 168, 14);
+    gSprites[sprite].invisible = TRUE;
+    gSprites[sprite].callback = callback;
+    return sprite;
+}
+
+void StoreWordInTwoHalfwords(u16 *h, u32 w)
+{
+    h[0] = (u16)(w);
+    h[1] = (u16)(w >> 16);
+}
+
+void LoadWordFromTwoHalfwords(u16 *h, u32 *w)
+{
+    *w = h[0] | (s16)h[1] << 16;
+}
+
+void SetBgAffineStruct(struct BgAffineSrcData *src, u32 texX, u32 texY, s16 scrX, s16 scrY, s16 sx, s16 sy, u16 alpha)
+{
+    src->texX = texX;
+    src->texY = texY;
+    src->scrX = scrX;
+    src->scrY = scrY;
+    src->sx = sx;
+    src->sy = sy;
+    src->alpha = alpha;
+}
+
+void DoBgAffineSet(struct BgAffineDstData *dest, u32 texX, u32 texY, s16 scrX, s16 scrY, s16 sx, s16 sy, u16 alpha)
+{
+    struct BgAffineSrcData src;
+
+    SetBgAffineStruct(&src, texX, texY, scrX, scrY, sx, sy, alpha);
+    BgAffineSet(&src, dest, 1);
+}
+
+#ifdef NONMATCHING
+
+// Functionally equivalent.
+// Only the two yflip loops don't match.
+void CopySpriteTiles(u8 shape, u8 size, u8 *tiles, u16 *tilemap, u8 *output)
+{
+    u8 x, y;
+    s8 i, j;
+    u8 xflip[32];
+    u8 h = sSpriteDimensions[shape][size][1];
+    u8 w = sSpriteDimensions[shape][size][0];
+
+    for (y = 0; y < h; y++)
+    {
+        int filler = 32 - w;
+
+        for (x = 0; x < w; x++)
+        {
+            int tile = (*tilemap & 0x3ff) * 32;
+            int attr = *tilemap & 0xc00;
+
+            if (attr == 0)
+            {
+                void *src = tiles + tile;
+                void *dest = output;
+                int length = 32;
+                DmaCopy32(3, src, dest, length);
+            }
+            else if (attr == 0x800)  // yflip
+            {
+                for (i = 0; i < 8; i++)
+                {
+                    void *src = tiles;
+                    void *dest = output;
+                    int length = 4;
+                    // this is likely wrong, but makes it closer to matching
+                    src += tile + (7 - i) * 4;
+                    dest += i * 4;
+                    DmaCopy32(3, src, dest, length);
+                }
+            }
+            else  // xflip
+            {
+                for (i = 0; i < 8; i++)
+                {
+                    for (j = 0; j < 4; j++)
+                    {
+                        u8 i2 = i * 4;
+                        xflip[i2 + (3-j)] = (tiles[tile + i2 + j] & 0xf) << 4;
+                        xflip[i2 + (3-j)] |= tiles[tile + i2 + j] >> 4;
+                    }
+                }
+                if (*tilemap & 0x800)  // yflip
+                {
+                    for (i = 0; i < 8; i++)
+                    {
+                        void *src = xflip + (7-i) * 4;
+                        void *dest = output + i*4;
+                        int length = 4;
+                        DmaCopy32(3, src, dest, length);
+                    }
+                }
+                else
+                {
+                    void *src = xflip;
+                    void *dest = output;
+                    int length = 32;
+                    DmaCopy32(3, src, dest, length);
+                }
+            }
+            tilemap++;
+            output += 32;
+        }
+        tilemap += filler;
+    }
+}
+
+#else
+__attribute__((naked)) void CopySpriteTiles(u8 shape, u8 size, u8 *tiles, u16 *tilemap, u8 *output)
+{
+    asm("\n\
+        .syntax unified\n\
+        push {r4-r7,lr}\n\
+        mov r7, r10\n\
+        mov r6, r9\n\
+        mov r5, r8\n\
+        push {r5-r7}\n\
+        sub sp, 0x38\n\
+        str r2, [sp, 0x20]\n\
+        adds r4, r3, 0\n\
+        ldr r7, [sp, 0x58]\n\
+        lsls r0, 24\n\
+        lsls r1, 24\n\
+        ldr r2, =sSpriteDimensions\n\
+        lsrs r1, 23\n\
+        lsrs r0, 21\n\
+        adds r1, r0\n\
+        adds r0, r2, 0x1\n\
+        adds r0, r1, r0\n\
+        ldrb r0, [r0]\n\
+        str r0, [sp, 0x24]\n\
+        adds r1, r2\n\
+        ldrb r1, [r1]\n\
+        str r1, [sp, 0x28]\n\
+        movs r0, 0\n\
+        b _0806F88C\n\
+        .pool\n\
+    _0806F740:\n\
+        movs r5, 0\n\
+        adds r0, 0x1\n\
+        str r0, [sp, 0x30]\n\
+        b _0806F874\n\
+    _0806F748:\n\
+        ldrh r0, [r4]\n\
+        ldr r2, =0x000003ff\n\
+        adds r1, r2, 0\n\
+        ands r1, r0\n\
+        lsls r1, 5\n\
+        mov r8, r1\n\
+        movs r2, 0xC0\n\
+        lsls r2, 4\n\
+        adds r1, r2, 0\n\
+        ands r1, r0\n\
+        mov r2, sp\n\
+        strh r0, [r2, 0x34]\n\
+        cmp r1, 0\n\
+        bne _0806F788\n\
+        ldr r0, [sp, 0x20]\n\
+        add r0, r8\n\
+        adds r1, r7, 0\n\
+        ldr r2, =0x04000008\n\
+        bl CpuSet\n\
+        adds r4, 0x2\n\
+        str r4, [sp, 0x2C]\n\
+        adds r7, 0x20\n\
+        mov r10, r7\n\
+        adds r5, 0x1\n\
+        mov r9, r5\n\
+        b _0806F86A\n\
+        .pool\n\
+    _0806F788:\n\
+        movs r0, 0x80\n\
+        lsls r0, 4\n\
+        cmp r1, r0\n\
+        bne _0806F7CC\n\
+        movs r1, 0\n\
+        adds r4, 0x2\n\
+        str r4, [sp, 0x2C]\n\
+        movs r2, 0x20\n\
+        adds r2, r7\n\
+        mov r10, r2\n\
+        adds r5, 0x1\n\
+        mov r9, r5\n\
+    _0806F7A0:\n\
+        lsls r4, r1, 24\n\
+        asrs r4, 24\n\
+        movs r0, 0x7\n\
+        subs r0, r4\n\
+        lsls r0, 2\n\
+        add r0, r8\n\
+        ldr r1, [sp, 0x20]\n\
+        adds r0, r1, r0\n\
+        lsls r1, r4, 2\n\
+        adds r1, r7, r1\n\
+        ldr r2, =0x04000001\n\
+        bl CpuSet\n\
+        adds r4, 0x1\n\
+        lsls r4, 24\n\
+        lsrs r1, r4, 24\n\
+        asrs r4, 24\n\
+        cmp r4, 0x7\n\
+        ble _0806F7A0\n\
+        b _0806F86A\n\
+        .pool\n\
+    _0806F7CC:\n\
+        movs r1, 0\n\
+        adds r4, 0x2\n\
+        str r4, [sp, 0x2C]\n\
+        movs r2, 0x20\n\
+        adds r2, r7\n\
+        mov r10, r2\n\
+        adds r5, 0x1\n\
+        mov r9, r5\n\
+        movs r0, 0xF\n\
+        mov r12, r0\n\
+    _0806F7E0:\n\
+        movs r2, 0\n\
+        lsls r4, r1, 24\n\
+        lsls r0, r4, 2\n\
+        lsrs r0, 24\n\
+        adds r6, r0, 0x3\n\
+        mov r1, r8\n\
+        adds r5, r1, r0\n\
+    _0806F7EE:\n\
+        lsls r1, r2, 24\n\
+        asrs r1, 24\n\
+        subs r0, r6, r1\n\
+        mov r2, sp\n\
+        adds r3, r2, r0\n\
+        adds r0, r5, r1\n\
+        ldr r2, [sp, 0x20]\n\
+        adds r0, r2, r0\n\
+        ldrb r2, [r0]\n\
+        mov r0, r12\n\
+        ands r0, r2\n\
+        lsls r0, 4\n\
+        lsrs r2, 4\n\
+        orrs r0, r2\n\
+        strb r0, [r3]\n\
+        adds r1, 0x1\n\
+        lsls r1, 24\n\
+        lsrs r2, r1, 24\n\
+        asrs r1, 24\n\
+        cmp r1, 0x3\n\
+        ble _0806F7EE\n\
+        movs r1, 0x80\n\
+        lsls r1, 17\n\
+        adds r0, r4, r1\n\
+        lsrs r1, r0, 24\n\
+        asrs r0, 24\n\
+        cmp r0, 0x7\n\
+        ble _0806F7E0\n\
+        mov r2, sp\n\
+        ldrh r0, [r2, 0x34]\n\
+        movs r2, 0x80\n\
+        lsls r2, 4\n\
+        ands r0, r2\n\
+        cmp r0, 0\n\
+        beq _0806F860\n\
+        movs r1, 0\n\
+    _0806F836:\n\
+        lsls r4, r1, 24\n\
+        asrs r4, 24\n\
+        movs r0, 0x7\n\
+        subs r0, r4\n\
+        lsls r0, 2\n\
+        add r0, sp\n\
+        lsls r1, r4, 2\n\
+        adds r1, r7, r1\n\
+        ldr r2, =0x04000001\n\
+        bl CpuSet\n\
+        adds r4, 0x1\n\
+        lsls r4, 24\n\
+        lsrs r1, r4, 24\n\
+        asrs r4, 24\n\
+        cmp r4, 0x7\n\
+        ble _0806F836\n\
+        b _0806F86A\n\
+        .pool\n\
+    _0806F860:\n\
+        mov r0, sp\n\
+        adds r1, r7, 0\n\
+        ldr r2, =0x04000008\n\
+        bl CpuSet\n\
+    _0806F86A:\n\
+        ldr r4, [sp, 0x2C]\n\
+        mov r7, r10\n\
+        mov r1, r9\n\
+        lsls r0, r1, 24\n\
+        lsrs r5, r0, 24\n\
+    _0806F874:\n\
+        ldr r2, [sp, 0x28]\n\
+        cmp r5, r2\n\
+        bcs _0806F87C\n\
+        b _0806F748\n\
+    _0806F87C:\n\
+        movs r0, 0x20\n\
+        ldr r1, [sp, 0x28]\n\
+        subs r0, r1\n\
+        lsls r0, 1\n\
+        adds r4, r0\n\
+        ldr r2, [sp, 0x30]\n\
+        lsls r0, r2, 24\n\
+        lsrs r0, 24\n\
+    _0806F88C:\n\
+        ldr r1, [sp, 0x24]\n\
+        cmp r0, r1\n\
+        bcs _0806F894\n\
+        b _0806F740\n\
+    _0806F894:\n\
+        add sp, 0x38\n\
+        pop {r3-r5}\n\
+        mov r8, r3\n\
+        mov r9, r4\n\
+        mov r10, r5\n\
+        pop {r4-r7}\n\
+        pop {r0}\n\
+        bx r0\n\
+        .pool\n\
+        .syntax divided");
+}
+
+#endif // NONMATCHING
+
+int CountTrailingZeroBits(u32 value)
+{
+    u8 i;
+
+    for (i = 0; i < 32; i++)
+    {
+        if ((value & 1) == 0)
+            value >>= 1;
+        else
+            return i;
+    }
+    return 0;
+}
+
+u16 CalcCRC16(u8 *data, s32 length)
+{
+    u16 i, j;
+    u16 crc = 0x1121;
+
+    for (i = 0; i < length; i++)
+    {
+        crc ^= data[i];
+        for (j = 0; j < 8; j++)
+        {
+            if (crc & 1)
+                crc = (crc >> 1) ^ 0x8408;
+            else
+                crc >>= 1;
+        }
+    }
+    return ~crc;
+}
+
+u16 CalcCRC16WithTable(u8 *data, u32 length)
+{
+    u16 i;
+    u16 crc = 0x1121;
+    u8 byte;
+
+    for (i = 0; i < length; i++)
+    {
+        byte = crc >> 8;
+        crc ^= data[i];
+        crc = byte ^ sCrc16Table[(u8)crc];
+    }
+    return ~crc;
+}
+
+u32 CalcByteArraySum(const u8* data, u32 length)
+{
+    u32 sum, i;
+    for (sum = 0, i = 0; i < length; i++)
+        sum += data[i];
+    return sum;
+}