From 0c25e25955f42e5349d3a458edd8bcbfc0040a01 Mon Sep 17 00:00:00 2001
From: Zur3l <90565581+Zur3l@users.noreply.github.com>
Date: Sat, 11 Jul 2026 15:59:13 -0400
Subject: [PATCH] Decomp MultiplyByFixedPoint

---
 asm/include/main_02001A30.inc |   2 -
 asm/include/main_02001AB0.inc |   4 +
 asm/main_02001A30.s           | 617 ----------------------------------
 asm/main_02001AB0.s           | 594 ++++++++++++++++++++++++++++++++
 include/main_02001A54.h       |   8 +
 main.lsf                      |   2 +
 src/main_02001A54.c           |  42 +++
 7 files changed, 650 insertions(+), 619 deletions(-)
 create mode 100644 asm/include/main_02001AB0.inc
 create mode 100644 asm/main_02001AB0.s
 create mode 100644 include/main_02001A54.h
 create mode 100644 src/main_02001A54.c

diff --git a/asm/include/main_02001A30.inc b/asm/include/main_02001A30.inc
index f8dc2970..6f70f09b 100644
--- a/asm/include/main_02001A30.inc
+++ b/asm/include/main_02001A30.inc
@@ -1,3 +1 @@
 #pragma once
-.public NATURAL_LOG_VALUE_TABLE
-.public PRNG_SEQUENCE_NUM
diff --git a/asm/include/main_02001AB0.inc b/asm/include/main_02001AB0.inc
new file mode 100644
index 00000000..1541e0d5
--- /dev/null
+++ b/asm/include/main_02001AB0.inc
@@ -0,0 +1,4 @@
+#pragma once
+.public NATURAL_LOG_VALUE_TABLE
+.public PRNG_SEQUENCE_NUM
+.public UFixedPoint64CmpLt
diff --git a/asm/main_02001A30.s b/asm/main_02001A30.s
index b47b63d6..c98d23b0 100644
--- a/asm/main_02001A30.s
+++ b/asm/main_02001A30.s
@@ -15,620 +15,3 @@ UFixedPoint64CmpLt: ; 0x02001A30
 	movhs r0, #0
 	bx lr
 	arm_func_end UFixedPoint64CmpLt
-
-	arm_func_start MultiplyByFixedPoint
-MultiplyByFixedPoint: ; 0x02001A54
-	stmdb sp!, {r3, r4, r5, lr}
-	tst r0, #0x80000000
-	movne r2, #1
-	moveq r2, #0
-	tst r1, #0x80000000
-	and r4, r2, #0xff
-	movne r2, #1
-	moveq r2, #0
-	cmp r0, #0
-	and r5, r2, #0xff
-	moveq r0, #0
-	ldmeqia sp!, {r3, r4, r5, pc}
-	cmp r1, #0
-	moveq r0, #0
-	ldmeqia sp!, {r3, r4, r5, pc}
-	cmp r4, #0
-	rsbne r0, r0, #0
-	cmp r5, #0
-	rsbne r1, r1, #0
-	bl UMultiplyByFixedPoint
-	cmp r4, r5
-	rsbne r0, r0, #0
-	ldmia sp!, {r3, r4, r5, pc}
-	arm_func_end MultiplyByFixedPoint
-
-	arm_func_start sub_02001AB0
-sub_02001AB0: ; 0x02001AB0
-	stmdb sp!, {r3, r4, r5, lr}
-	tst r0, #0x80000000
-	movne r2, #1
-	moveq r2, #0
-	tst r1, #0x80000000
-	and r4, r2, #0xff
-	movne r2, #1
-	moveq r2, #0
-	cmp r1, #0
-	and r5, r2, #0xff
-	mvneq r0, #0x80000000
-	ldmeqia sp!, {r3, r4, r5, pc}
-	cmp r0, #0
-	moveq r0, #0
-	ldmeqia sp!, {r3, r4, r5, pc}
-	cmp r4, #0
-	rsbne r0, r0, #0
-	cmp r5, #0
-	rsbne r1, r1, #0
-	bl sub_02001BB4
-	cmp r4, r5
-	rsbne r0, r0, #0
-	ldmia sp!, {r3, r4, r5, pc}
-	arm_func_end sub_02001AB0
-
-	arm_func_start UMultiplyByFixedPoint
-UMultiplyByFixedPoint: ; 0x02001B0C
-	stmdb sp!, {r3, r4, r5, lr}
-	cmp r0, #0
-	moveq r0, #0
-	ldmeqia sp!, {r3, r4, r5, pc}
-	cmp r1, #0
-	moveq r0, #0
-	ldmeqia sp!, {r3, r4, r5, pc}
-	mov r3, #0
-	mov r2, r3
-	mov ip, r3
-	mov lr, r3
-	mov r4, r3
-_02001B3C:
-	mov r5, lr
-	tst r1, #1
-	beq _02001B58
-	add lr, lr, r0
-	add ip, ip, r3
-	cmp r5, lr
-	addhi ip, ip, #1
-_02001B58:
-	mov r1, r1, lsr #1
-	tst r2, #1
-	orrne r1, r1, #0x80000000
-	mov r2, r2, lsr #1
-	tst r0, #0x80000000
-	mov r3, r3, lsl #1
-	mov r0, r0, lsl #1
-	add r4, r4, #1
-	orrne r3, r3, #1
-	bic r2, r2, #0x80000000
-	cmp r4, #0x40
-	bic r0, r0, #1
-	blt _02001B3C
-	mov r0, lr, lsr #8
-	tst lr, #0x80
-	movne r1, #1
-	bic r0, r0, #0xff000000
-	moveq r1, #0
-	orr lr, r0, ip, lsl #24
-	tst r1, #0xff
-	addne lr, lr, #1
-	mov r0, lr
-	ldmia sp!, {r3, r4, r5, pc}
-	arm_func_end UMultiplyByFixedPoint
-
-	arm_func_start sub_02001BB4
-sub_02001BB4: ; 0x02001BB4
-	stmdb sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, lr}
-	movs sl, r1
-	mvneq r0, #0x80000000
-	ldmeqia sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, pc}
-	cmp r0, #0
-	moveq r0, #0
-	ldmeqia sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, pc}
-	mov r8, #0
-	mov r1, r0, asr #0x18
-	mov r0, r0, lsl #8
-	mov r4, r8
-	mov r5, r8
-	mov sb, r8
-	and r6, r1, #0xff
-	bic r7, r0, #0xff
-	mov fp, r8
-_02001BF4:
-	mov r0, r5, lsl #1
-	tst r5, #0x80000000
-	mov r4, r4, lsl #1
-	orrne r4, r4, #1
-	bic r5, r0, #1
-	tst r6, #0x80000000
-	orrne r5, r5, #1
-	mov r3, r7, lsl #1
-	tst r7, #0x80000000
-	mov r6, r6, lsl #1
-	bic r7, r3, #1
-	mov r0, r4
-	mov r1, r5
-	mov r2, fp
-	mov r3, sl
-	orrne r6, r6, #1
-	bl UFixedPoint64CmpLt
-	cmp r0, #0
-	bne _02001C58
-	mov r0, r5
-	sub r5, r5, sl
-	cmp r0, r5
-	mov r1, #1
-	sublo r4, r4, #1
-	b _02001C5C
-_02001C58:
-	mov r1, #0
-_02001C5C:
-	mov r0, r8, lsl #1
-	bic r8, r0, #1
-	cmp r1, #0
-	add sb, sb, #1
-	orrne r8, r8, #1
-	cmp sb, #0x40
-	blt _02001BF4
-	mov r0, r8
-	ldmia sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, pc}
-	arm_func_end sub_02001BB4
-
-	arm_func_start IntToFixedPoint64
-IntToFixedPoint64: ; 0x02001C80
-	mov r2, #0x10000
-	rsb r2, r2, #0
-	and r3, r1, r2
-	mov r3, r3, lsr #0x10
-	str r3, [r0]
-	mov r3, r1, lsl #0x10
-	str r3, [r0, #4]
-	tst r1, #0x8000
-	ldrne r1, [r0]
-	orrne r1, r1, r2
-	strne r1, [r0]
-	bx lr
-	arm_func_end IntToFixedPoint64
-
-	arm_func_start FixedPoint64ToInt
-FixedPoint64ToInt: ; 0x02001CB0
-	ldmia r0, {r1, r2}
-	mov r0, #0x10000
-	rsb r0, r0, #0
-	mov r1, r1, lsl #0x10
-	and r0, r2, r0
-	orr r0, r1, r0, lsr #16
-	tst r2, #0x8000
-	addne r0, r0, #1
-	bx lr
-	arm_func_end FixedPoint64ToInt
-
-	arm_func_start FixedPoint32To64
-FixedPoint32To64: ; 0x02001CD4
-	mov r2, r1, asr #0x18
-	mov r3, r1, lsl #8
-	tst r2, #0x80
-	mvnne r1, #0x7f
-	orrne r1, r2, r1
-	stmia r0, {r2, r3}
-	andeq r1, r2, #0x7f
-	str r1, [r0]
-	bx lr
-	arm_func_end FixedPoint32To64
-
-	arm_func_start NegateFixedPoint64
-NegateFixedPoint64: ; 0x02001CF8
-	ldr r2, [r0]
-	mvn r1, #0
-	eor r2, r2, r1
-	str r2, [r0]
-	ldr r2, [r0, #4]
-	eor r2, r2, r1
-	adds r1, r2, #1
-	str r1, [r0, #4]
-	ldreq r1, [r0]
-	addeq r1, r1, #1
-	streq r1, [r0]
-	bx lr
-	arm_func_end NegateFixedPoint64
-
-	arm_func_start FixedPoint64IsZero
-FixedPoint64IsZero: ; 0x02001D28
-	ldr r1, [r0]
-	cmp r1, #0
-	movne r0, #0
-	bxne lr
-	ldr r0, [r0, #4]
-	cmp r0, #0
-	moveq r0, #1
-	movne r0, #0
-	and r0, r0, #0xff
-	bx lr
-	arm_func_end FixedPoint64IsZero
-
-	arm_func_start FixedPoint64IsNegative
-FixedPoint64IsNegative: ; 0x02001D50
-	ldr r0, [r0]
-	tst r0, #0x80000000
-	movne r0, #1
-	moveq r0, #0
-	and r0, r0, #0xff
-	bx lr
-	arm_func_end FixedPoint64IsNegative
-
-	arm_func_start FixedPoint64CmpLt
-FixedPoint64CmpLt: ; 0x02001D68
-	stmdb sp!, {r3, lr}
-	mov ip, r1
-	ldr r2, [ip]
-	mov lr, r0
-	tst r2, #0x80000000
-	movne r1, #2
-	ldr r0, [lr]
-	moveq r1, #0
-	tst r0, #0x80000000
-	movne r3, #1
-	moveq r3, #0
-	orr r1, r3, r1
-	cmp r1, #3
-	addls pc, pc, r1, lsl #2
-	b _02001DB4
-_02001DA4: ; jump table
-	b _02001DB4 ; case 0
-	b _02001DC4 ; case 1
-	b _02001DCC ; case 2
-	b _02001DD4 ; case 3
-_02001DB4:
-	ldr r1, [lr, #4]
-	ldr r3, [ip, #4]
-	bl UFixedPoint64CmpLt
-	ldmia sp!, {r3, pc}
-_02001DC4:
-	mov r0, #1
-	ldmia sp!, {r3, pc}
-_02001DCC:
-	mov r0, #0
-	ldmia sp!, {r3, pc}
-_02001DD4:
-	ldr r1, [lr, #4]
-	ldr r3, [ip, #4]
-	bl UFixedPoint64CmpLt
-	cmp r0, #0
-	moveq r0, #1
-	movne r0, #0
-	and r0, r0, #0xff
-	ldmia sp!, {r3, pc}
-	arm_func_end FixedPoint64CmpLt
-
-	arm_func_start MultiplyFixedPoint64
-MultiplyFixedPoint64: ; 0x02001DF4
-	stmdb sp!, {r4, r5, r6, lr}
-	sub sp, sp, #0x18
-	ldr r3, [r1]
-	mov r4, r0
-	str r3, [sp, #0x10]
-	ldr r1, [r1, #4]
-	add r0, sp, #0x10
-	str r1, [sp, #0x14]
-	ldr r1, [r2]
-	str r1, [sp, #8]
-	ldr r1, [r2, #4]
-	str r1, [sp, #0xc]
-	bl FixedPoint64IsNegative
-	mov r5, r0
-	add r0, sp, #8
-	bl FixedPoint64IsNegative
-	mov r6, r0
-	add r0, sp, #0x10
-	bl FixedPoint64IsZero
-	cmp r0, #0
-	movne r0, #0
-	strne r0, [r4]
-	strne r0, [r4, #4]
-	bne _02001EC0
-	add r0, sp, #8
-	bl FixedPoint64IsZero
-	cmp r0, #0
-	movne r0, #0
-	strne r0, [r4]
-	strne r0, [r4, #4]
-	bne _02001EC0
-	cmp r5, #0
-	beq _02001E80
-	add r0, sp, #0x10
-	bl NegateFixedPoint64
-_02001E80:
-	cmp r6, #0
-	beq _02001E90
-	add r0, sp, #8
-	bl NegateFixedPoint64
-_02001E90:
-	add r0, sp, #0
-	add r1, sp, #0x10
-	add r2, sp, #8
-	bl UMultiplyFixedPoint64
-	cmp r5, r6
-	beq _02001EB0
-	add r0, sp, #0
-	bl NegateFixedPoint64
-_02001EB0:
-	ldr r0, [sp]
-	str r0, [r4]
-	ldr r0, [sp, #4]
-	str r0, [r4, #4]
-_02001EC0:
-	add sp, sp, #0x18
-	ldmia sp!, {r4, r5, r6, pc}
-	arm_func_end MultiplyFixedPoint64
-
-	arm_func_start DivideFixedPoint64
-DivideFixedPoint64: ; 0x02001EC8
-	stmdb sp!, {r4, r5, r6, lr}
-	sub sp, sp, #0x18
-	ldr r3, [r1]
-	mov r4, r0
-	str r3, [sp, #0x10]
-	ldr r1, [r1, #4]
-	add r0, sp, #0x10
-	str r1, [sp, #0x14]
-	ldr r1, [r2]
-	str r1, [sp, #8]
-	ldr r1, [r2, #4]
-	str r1, [sp, #0xc]
-	bl FixedPoint64IsNegative
-	mov r5, r0
-	add r0, sp, #8
-	bl FixedPoint64IsNegative
-	mov r6, r0
-	add r0, sp, #8
-	bl FixedPoint64IsZero
-	cmp r0, #0
-	mvnne r0, #0x80000000
-	strne r0, [r4]
-	subne r0, r0, #0x80000000
-	strne r0, [r4, #4]
-	bne _02001F98
-	add r0, sp, #0x10
-	bl FixedPoint64IsZero
-	cmp r0, #0
-	movne r0, #0
-	strne r0, [r4]
-	strne r0, [r4, #4]
-	bne _02001F98
-	cmp r5, #0
-	beq _02001F58
-	add r0, sp, #0x10
-	bl NegateFixedPoint64
-_02001F58:
-	cmp r6, #0
-	beq _02001F68
-	add r0, sp, #8
-	bl NegateFixedPoint64
-_02001F68:
-	add r0, sp, #0
-	add r1, sp, #0x10
-	add r2, sp, #8
-	bl UDivideFixedPoint64
-	cmp r5, r6
-	beq _02001F88
-	add r0, sp, #0
-	bl NegateFixedPoint64
-_02001F88:
-	ldr r0, [sp]
-	str r0, [r4]
-	ldr r0, [sp, #4]
-	str r0, [r4, #4]
-_02001F98:
-	add sp, sp, #0x18
-	ldmia sp!, {r4, r5, r6, pc}
-	arm_func_end DivideFixedPoint64
-
-	arm_func_start UMultiplyFixedPoint64
-UMultiplyFixedPoint64: ; 0x02001FA0
-	stmdb sp!, {r4, r5, r6, lr}
-	mov r6, r1
-	mov r4, r0
-	mov r0, r6
-	mov r5, r2
-	bl FixedPoint64IsZero
-	cmp r0, #0
-	movne r0, #0
-	strne r0, [r4]
-	strne r0, [r4, #4]
-	ldmneia sp!, {r4, r5, r6, pc}
-	mov r0, r5
-	bl FixedPoint64IsZero
-	cmp r0, #0
-	movne r0, #0
-	strne r0, [r4]
-	strne r0, [r4, #4]
-	ldmneia sp!, {r4, r5, r6, pc}
-	mov lr, #0
-	ldmia r6, {r1, r2}
-	ldmia r5, {r3, ip}
-	mov r5, lr
-	mov r6, lr
-_02001FFC:
-	mov r0, r5
-	tst ip, #1
-	beq _02002018
-	add r5, r5, r2
-	add lr, lr, r1
-	cmp r0, r5
-	addhi lr, lr, #1
-_02002018:
-	mov r0, r3, lsr #1
-	tst r3, #1
-	mov ip, ip, lsr #1
-	bic r3, r0, #0x80000000
-	orrne ip, ip, #0x80000000
-	mov r1, r1, lsl #1
-	tst r2, #0x80000000
-	mov r0, r2, lsl #1
-	add r6, r6, #1
-	orrne r1, r1, #1
-	cmp r6, #0x40
-	bic r2, r0, #1
-	blt _02001FFC
-	mov r0, r5, lsr #0x10
-	mov r0, r0, lsl #0x10
-	tst r5, #0x8000
-	mov r1, lr, lsl #0x10
-	movne r2, #1
-	orr r5, r1, r0, lsr #16
-	mov r0, lr, lsr #0x10
-	moveq r2, #0
-	mov r0, r0, lsl #0x10
-	tst r2, #0xff
-	addne r5, r5, #1
-	mov r0, r0, lsr #0x10
-	stmia r4, {r0, r5}
-	ldmia sp!, {r4, r5, r6, pc}
-	arm_func_end UMultiplyFixedPoint64
-
-	arm_func_start UDivideFixedPoint64
-UDivideFixedPoint64: ; 0x02002084
-	stmdb sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, lr}
-	sub sp, sp, #8
-	mov r4, r2
-	mov sl, r0
-	mov r0, r4
-	mov r5, r1
-	bl FixedPoint64IsZero
-	cmp r0, #0
-	mvnne r0, #0x80000000
-	strne r0, [sl]
-	subne r0, r0, #0x80000000
-	strne r0, [sl, #4]
-	bne _020021C0
-	mov r0, r5
-	bl FixedPoint64IsZero
-	cmp r0, #0
-	movne r0, #0
-	strne r0, [sl]
-	strne r0, [sl, #4]
-	bne _020021C0
-	ldr r2, [r5, #4]
-	mov r0, #0x10000
-	mov r1, r2, lsr #0x10
-	mov r8, #0
-	ldr r3, [r5]
-	rsb r0, r0, #0
-	and r2, r0, r2, lsl #16
-	and r3, r0, r3, lsl #16
-	ldr r0, [r4]
-	mov r1, r1, lsl #0x10
-	ldr fp, [r4, #4]
-	str r0, [sp, #4]
-	mov sb, r8
-	mov r4, r8
-	mov r5, r8
-	str r8, [sp]
-	orr r6, r3, r1, lsr #16
-	orr r7, r2, #0x8000
-_0200211C:
-	mov r0, r5, lsl #1
-	tst r5, #0x80000000
-	mov r4, r4, lsl #1
-	orrne r4, r4, #1
-	bic r5, r0, #1
-	tst r6, #0x80000000
-	orrne r5, r5, #1
-	mov r1, r7, lsl #1
-	tst r7, #0x80000000
-	mov r6, r6, lsl #1
-	bic r7, r1, #1
-	ldr r2, [sp, #4]
-	mov r0, r4
-	mov r1, r5
-	mov r3, fp
-	orrne r6, r6, #1
-	bl UFixedPoint64CmpLt
-	cmp r0, #0
-	bne _02002188
-	mov r0, r5
-	sub r5, r5, fp
-	cmp r0, r5
-	ldr r0, [sp, #4]
-	mov r1, #1
-	sub r4, r4, r0
-	sublo r4, r4, #1
-	b _0200218C
-_02002188:
-	mov r1, #0
-_0200218C:
-	mov r0, sb, lsl #1
-	tst sb, #0x80000000
-	bic sb, r0, #1
-	ldr r0, [sp]
-	mov r8, r8, lsl #1
-	add r0, r0, #1
-	orrne r8, r8, #1
-	cmp r1, #0
-	orrne sb, sb, #1
-	str r0, [sp]
-	cmp r0, #0x40
-	blt _0200211C
-	stmia sl, {r8, sb}
-_020021C0:
-	add sp, sp, #8
-	ldmia sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, pc}
-	arm_func_end UDivideFixedPoint64
-
-	arm_func_start AddFixedPoint64
-AddFixedPoint64: ; 0x020021C8
-	stmdb sp!, {r3, lr}
-	ldr ip, [r1, #4]
-	ldr lr, [r1]
-	ldr r1, [r2]
-	ldr r3, [r2, #4]
-	add r1, lr, r1
-	add r2, ip, r3
-	cmp r2, ip
-	addlo r1, r1, #1
-	stmia r0, {r1, r2}
-	ldmia sp!, {r3, pc}
-	arm_func_end AddFixedPoint64
-
-	arm_func_start ClampedLn
-ClampedLn: ; 0x020021F4
-	cmp r1, #1
-	movlt r1, #1
-	cmp r1, #0x800
-	ldrge r1, _02002220 ; =0x000007FF
-	ldr r2, _02002224 ; =NATURAL_LOG_VALUE_TABLE
-	mov r1, r1, lsl #1
-	ldrsh r2, [r2, r1]
-	mov r1, #0
-	mov r2, r2, lsl #4
-	stmia r0, {r1, r2}
-	bx lr
-	.align 2, 0
-_02002220: .word 0x000007FF
-_02002224: .word NATURAL_LOG_VALUE_TABLE
-	arm_func_end ClampedLn
-
-	arm_func_start sub_02002228
-sub_02002228: ; 0x02002228
-	bx lr
-	arm_func_end sub_02002228
-
-	arm_func_start GetRngSeed
-GetRngSeed: ; 0x0200222C
-	ldr r0, _02002238 ; =PRNG_SEQUENCE_NUM
-	ldrh r0, [r0]
-	bx lr
-	.align 2, 0
-_02002238: .word PRNG_SEQUENCE_NUM
-	arm_func_end GetRngSeed
-
-	arm_func_start SetRngSeed
-SetRngSeed: ; 0x0200223C
-	ldr r1, _02002248 ; =PRNG_SEQUENCE_NUM
-	strh r0, [r1]
-	bx lr
-	.align 2, 0
-_02002248: .word PRNG_SEQUENCE_NUM
-	arm_func_end SetRngSeed
diff --git a/asm/main_02001AB0.s b/asm/main_02001AB0.s
new file mode 100644
index 00000000..17e3eeb4
--- /dev/null
+++ b/asm/main_02001AB0.s
@@ -0,0 +1,594 @@
+	.include "asm/macros.inc"
+	.include "main_02001AB0.inc"
+
+	.text
+
+	arm_func_start sub_02001AB0
+sub_02001AB0: ; 0x02001AB0
+	stmdb sp!, {r3, r4, r5, lr}
+	tst r0, #0x80000000
+	movne r2, #1
+	moveq r2, #0
+	tst r1, #0x80000000
+	and r4, r2, #0xff
+	movne r2, #1
+	moveq r2, #0
+	cmp r1, #0
+	and r5, r2, #0xff
+	mvneq r0, #0x80000000
+	ldmeqia sp!, {r3, r4, r5, pc}
+	cmp r0, #0
+	moveq r0, #0
+	ldmeqia sp!, {r3, r4, r5, pc}
+	cmp r4, #0
+	rsbne r0, r0, #0
+	cmp r5, #0
+	rsbne r1, r1, #0
+	bl sub_02001BB4
+	cmp r4, r5
+	rsbne r0, r0, #0
+	ldmia sp!, {r3, r4, r5, pc}
+	arm_func_end sub_02001AB0
+
+	arm_func_start UMultiplyByFixedPoint
+UMultiplyByFixedPoint: ; 0x02001B0C
+	stmdb sp!, {r3, r4, r5, lr}
+	cmp r0, #0
+	moveq r0, #0
+	ldmeqia sp!, {r3, r4, r5, pc}
+	cmp r1, #0
+	moveq r0, #0
+	ldmeqia sp!, {r3, r4, r5, pc}
+	mov r3, #0
+	mov r2, r3
+	mov ip, r3
+	mov lr, r3
+	mov r4, r3
+_02001B3C:
+	mov r5, lr
+	tst r1, #1
+	beq _02001B58
+	add lr, lr, r0
+	add ip, ip, r3
+	cmp r5, lr
+	addhi ip, ip, #1
+_02001B58:
+	mov r1, r1, lsr #1
+	tst r2, #1
+	orrne r1, r1, #0x80000000
+	mov r2, r2, lsr #1
+	tst r0, #0x80000000
+	mov r3, r3, lsl #1
+	mov r0, r0, lsl #1
+	add r4, r4, #1
+	orrne r3, r3, #1
+	bic r2, r2, #0x80000000
+	cmp r4, #0x40
+	bic r0, r0, #1
+	blt _02001B3C
+	mov r0, lr, lsr #8
+	tst lr, #0x80
+	movne r1, #1
+	bic r0, r0, #0xff000000
+	moveq r1, #0
+	orr lr, r0, ip, lsl #24
+	tst r1, #0xff
+	addne lr, lr, #1
+	mov r0, lr
+	ldmia sp!, {r3, r4, r5, pc}
+	arm_func_end UMultiplyByFixedPoint
+
+	arm_func_start sub_02001BB4
+sub_02001BB4: ; 0x02001BB4
+	stmdb sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, lr}
+	movs sl, r1
+	mvneq r0, #0x80000000
+	ldmeqia sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, pc}
+	cmp r0, #0
+	moveq r0, #0
+	ldmeqia sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, pc}
+	mov r8, #0
+	mov r1, r0, asr #0x18
+	mov r0, r0, lsl #8
+	mov r4, r8
+	mov r5, r8
+	mov sb, r8
+	and r6, r1, #0xff
+	bic r7, r0, #0xff
+	mov fp, r8
+_02001BF4:
+	mov r0, r5, lsl #1
+	tst r5, #0x80000000
+	mov r4, r4, lsl #1
+	orrne r4, r4, #1
+	bic r5, r0, #1
+	tst r6, #0x80000000
+	orrne r5, r5, #1
+	mov r3, r7, lsl #1
+	tst r7, #0x80000000
+	mov r6, r6, lsl #1
+	bic r7, r3, #1
+	mov r0, r4
+	mov r1, r5
+	mov r2, fp
+	mov r3, sl
+	orrne r6, r6, #1
+	bl UFixedPoint64CmpLt
+	cmp r0, #0
+	bne _02001C58
+	mov r0, r5
+	sub r5, r5, sl
+	cmp r0, r5
+	mov r1, #1
+	sublo r4, r4, #1
+	b _02001C5C
+_02001C58:
+	mov r1, #0
+_02001C5C:
+	mov r0, r8, lsl #1
+	bic r8, r0, #1
+	cmp r1, #0
+	add sb, sb, #1
+	orrne r8, r8, #1
+	cmp sb, #0x40
+	blt _02001BF4
+	mov r0, r8
+	ldmia sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, pc}
+	arm_func_end sub_02001BB4
+
+	arm_func_start IntToFixedPoint64
+IntToFixedPoint64: ; 0x02001C80
+	mov r2, #0x10000
+	rsb r2, r2, #0
+	and r3, r1, r2
+	mov r3, r3, lsr #0x10
+	str r3, [r0]
+	mov r3, r1, lsl #0x10
+	str r3, [r0, #4]
+	tst r1, #0x8000
+	ldrne r1, [r0]
+	orrne r1, r1, r2
+	strne r1, [r0]
+	bx lr
+	arm_func_end IntToFixedPoint64
+
+	arm_func_start FixedPoint64ToInt
+FixedPoint64ToInt: ; 0x02001CB0
+	ldmia r0, {r1, r2}
+	mov r0, #0x10000
+	rsb r0, r0, #0
+	mov r1, r1, lsl #0x10
+	and r0, r2, r0
+	orr r0, r1, r0, lsr #16
+	tst r2, #0x8000
+	addne r0, r0, #1
+	bx lr
+	arm_func_end FixedPoint64ToInt
+
+	arm_func_start FixedPoint32To64
+FixedPoint32To64: ; 0x02001CD4
+	mov r2, r1, asr #0x18
+	mov r3, r1, lsl #8
+	tst r2, #0x80
+	mvnne r1, #0x7f
+	orrne r1, r2, r1
+	stmia r0, {r2, r3}
+	andeq r1, r2, #0x7f
+	str r1, [r0]
+	bx lr
+	arm_func_end FixedPoint32To64
+
+	arm_func_start NegateFixedPoint64
+NegateFixedPoint64: ; 0x02001CF8
+	ldr r2, [r0]
+	mvn r1, #0
+	eor r2, r2, r1
+	str r2, [r0]
+	ldr r2, [r0, #4]
+	eor r2, r2, r1
+	adds r1, r2, #1
+	str r1, [r0, #4]
+	ldreq r1, [r0]
+	addeq r1, r1, #1
+	streq r1, [r0]
+	bx lr
+	arm_func_end NegateFixedPoint64
+
+	arm_func_start FixedPoint64IsZero
+FixedPoint64IsZero: ; 0x02001D28
+	ldr r1, [r0]
+	cmp r1, #0
+	movne r0, #0
+	bxne lr
+	ldr r0, [r0, #4]
+	cmp r0, #0
+	moveq r0, #1
+	movne r0, #0
+	and r0, r0, #0xff
+	bx lr
+	arm_func_end FixedPoint64IsZero
+
+	arm_func_start FixedPoint64IsNegative
+FixedPoint64IsNegative: ; 0x02001D50
+	ldr r0, [r0]
+	tst r0, #0x80000000
+	movne r0, #1
+	moveq r0, #0
+	and r0, r0, #0xff
+	bx lr
+	arm_func_end FixedPoint64IsNegative
+
+	arm_func_start FixedPoint64CmpLt
+FixedPoint64CmpLt: ; 0x02001D68
+	stmdb sp!, {r3, lr}
+	mov ip, r1
+	ldr r2, [ip]
+	mov lr, r0
+	tst r2, #0x80000000
+	movne r1, #2
+	ldr r0, [lr]
+	moveq r1, #0
+	tst r0, #0x80000000
+	movne r3, #1
+	moveq r3, #0
+	orr r1, r3, r1
+	cmp r1, #3
+	addls pc, pc, r1, lsl #2
+	b _02001DB4
+_02001DA4: ; jump table
+	b _02001DB4 ; case 0
+	b _02001DC4 ; case 1
+	b _02001DCC ; case 2
+	b _02001DD4 ; case 3
+_02001DB4:
+	ldr r1, [lr, #4]
+	ldr r3, [ip, #4]
+	bl UFixedPoint64CmpLt
+	ldmia sp!, {r3, pc}
+_02001DC4:
+	mov r0, #1
+	ldmia sp!, {r3, pc}
+_02001DCC:
+	mov r0, #0
+	ldmia sp!, {r3, pc}
+_02001DD4:
+	ldr r1, [lr, #4]
+	ldr r3, [ip, #4]
+	bl UFixedPoint64CmpLt
+	cmp r0, #0
+	moveq r0, #1
+	movne r0, #0
+	and r0, r0, #0xff
+	ldmia sp!, {r3, pc}
+	arm_func_end FixedPoint64CmpLt
+
+	arm_func_start MultiplyFixedPoint64
+MultiplyFixedPoint64: ; 0x02001DF4
+	stmdb sp!, {r4, r5, r6, lr}
+	sub sp, sp, #0x18
+	ldr r3, [r1]
+	mov r4, r0
+	str r3, [sp, #0x10]
+	ldr r1, [r1, #4]
+	add r0, sp, #0x10
+	str r1, [sp, #0x14]
+	ldr r1, [r2]
+	str r1, [sp, #8]
+	ldr r1, [r2, #4]
+	str r1, [sp, #0xc]
+	bl FixedPoint64IsNegative
+	mov r5, r0
+	add r0, sp, #8
+	bl FixedPoint64IsNegative
+	mov r6, r0
+	add r0, sp, #0x10
+	bl FixedPoint64IsZero
+	cmp r0, #0
+	movne r0, #0
+	strne r0, [r4]
+	strne r0, [r4, #4]
+	bne _02001EC0
+	add r0, sp, #8
+	bl FixedPoint64IsZero
+	cmp r0, #0
+	movne r0, #0
+	strne r0, [r4]
+	strne r0, [r4, #4]
+	bne _02001EC0
+	cmp r5, #0
+	beq _02001E80
+	add r0, sp, #0x10
+	bl NegateFixedPoint64
+_02001E80:
+	cmp r6, #0
+	beq _02001E90
+	add r0, sp, #8
+	bl NegateFixedPoint64
+_02001E90:
+	add r0, sp, #0
+	add r1, sp, #0x10
+	add r2, sp, #8
+	bl UMultiplyFixedPoint64
+	cmp r5, r6
+	beq _02001EB0
+	add r0, sp, #0
+	bl NegateFixedPoint64
+_02001EB0:
+	ldr r0, [sp]
+	str r0, [r4]
+	ldr r0, [sp, #4]
+	str r0, [r4, #4]
+_02001EC0:
+	add sp, sp, #0x18
+	ldmia sp!, {r4, r5, r6, pc}
+	arm_func_end MultiplyFixedPoint64
+
+	arm_func_start DivideFixedPoint64
+DivideFixedPoint64: ; 0x02001EC8
+	stmdb sp!, {r4, r5, r6, lr}
+	sub sp, sp, #0x18
+	ldr r3, [r1]
+	mov r4, r0
+	str r3, [sp, #0x10]
+	ldr r1, [r1, #4]
+	add r0, sp, #0x10
+	str r1, [sp, #0x14]
+	ldr r1, [r2]
+	str r1, [sp, #8]
+	ldr r1, [r2, #4]
+	str r1, [sp, #0xc]
+	bl FixedPoint64IsNegative
+	mov r5, r0
+	add r0, sp, #8
+	bl FixedPoint64IsNegative
+	mov r6, r0
+	add r0, sp, #8
+	bl FixedPoint64IsZero
+	cmp r0, #0
+	mvnne r0, #0x80000000
+	strne r0, [r4]
+	subne r0, r0, #0x80000000
+	strne r0, [r4, #4]
+	bne _02001F98
+	add r0, sp, #0x10
+	bl FixedPoint64IsZero
+	cmp r0, #0
+	movne r0, #0
+	strne r0, [r4]
+	strne r0, [r4, #4]
+	bne _02001F98
+	cmp r5, #0
+	beq _02001F58
+	add r0, sp, #0x10
+	bl NegateFixedPoint64
+_02001F58:
+	cmp r6, #0
+	beq _02001F68
+	add r0, sp, #8
+	bl NegateFixedPoint64
+_02001F68:
+	add r0, sp, #0
+	add r1, sp, #0x10
+	add r2, sp, #8
+	bl UDivideFixedPoint64
+	cmp r5, r6
+	beq _02001F88
+	add r0, sp, #0
+	bl NegateFixedPoint64
+_02001F88:
+	ldr r0, [sp]
+	str r0, [r4]
+	ldr r0, [sp, #4]
+	str r0, [r4, #4]
+_02001F98:
+	add sp, sp, #0x18
+	ldmia sp!, {r4, r5, r6, pc}
+	arm_func_end DivideFixedPoint64
+
+	arm_func_start UMultiplyFixedPoint64
+UMultiplyFixedPoint64: ; 0x02001FA0
+	stmdb sp!, {r4, r5, r6, lr}
+	mov r6, r1
+	mov r4, r0
+	mov r0, r6
+	mov r5, r2
+	bl FixedPoint64IsZero
+	cmp r0, #0
+	movne r0, #0
+	strne r0, [r4]
+	strne r0, [r4, #4]
+	ldmneia sp!, {r4, r5, r6, pc}
+	mov r0, r5
+	bl FixedPoint64IsZero
+	cmp r0, #0
+	movne r0, #0
+	strne r0, [r4]
+	strne r0, [r4, #4]
+	ldmneia sp!, {r4, r5, r6, pc}
+	mov lr, #0
+	ldmia r6, {r1, r2}
+	ldmia r5, {r3, ip}
+	mov r5, lr
+	mov r6, lr
+_02001FFC:
+	mov r0, r5
+	tst ip, #1
+	beq _02002018
+	add r5, r5, r2
+	add lr, lr, r1
+	cmp r0, r5
+	addhi lr, lr, #1
+_02002018:
+	mov r0, r3, lsr #1
+	tst r3, #1
+	mov ip, ip, lsr #1
+	bic r3, r0, #0x80000000
+	orrne ip, ip, #0x80000000
+	mov r1, r1, lsl #1
+	tst r2, #0x80000000
+	mov r0, r2, lsl #1
+	add r6, r6, #1
+	orrne r1, r1, #1
+	cmp r6, #0x40
+	bic r2, r0, #1
+	blt _02001FFC
+	mov r0, r5, lsr #0x10
+	mov r0, r0, lsl #0x10
+	tst r5, #0x8000
+	mov r1, lr, lsl #0x10
+	movne r2, #1
+	orr r5, r1, r0, lsr #16
+	mov r0, lr, lsr #0x10
+	moveq r2, #0
+	mov r0, r0, lsl #0x10
+	tst r2, #0xff
+	addne r5, r5, #1
+	mov r0, r0, lsr #0x10
+	stmia r4, {r0, r5}
+	ldmia sp!, {r4, r5, r6, pc}
+	arm_func_end UMultiplyFixedPoint64
+
+	arm_func_start UDivideFixedPoint64
+UDivideFixedPoint64: ; 0x02002084
+	stmdb sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, lr}
+	sub sp, sp, #8
+	mov r4, r2
+	mov sl, r0
+	mov r0, r4
+	mov r5, r1
+	bl FixedPoint64IsZero
+	cmp r0, #0
+	mvnne r0, #0x80000000
+	strne r0, [sl]
+	subne r0, r0, #0x80000000
+	strne r0, [sl, #4]
+	bne _020021C0
+	mov r0, r5
+	bl FixedPoint64IsZero
+	cmp r0, #0
+	movne r0, #0
+	strne r0, [sl]
+	strne r0, [sl, #4]
+	bne _020021C0
+	ldr r2, [r5, #4]
+	mov r0, #0x10000
+	mov r1, r2, lsr #0x10
+	mov r8, #0
+	ldr r3, [r5]
+	rsb r0, r0, #0
+	and r2, r0, r2, lsl #16
+	and r3, r0, r3, lsl #16
+	ldr r0, [r4]
+	mov r1, r1, lsl #0x10
+	ldr fp, [r4, #4]
+	str r0, [sp, #4]
+	mov sb, r8
+	mov r4, r8
+	mov r5, r8
+	str r8, [sp]
+	orr r6, r3, r1, lsr #16
+	orr r7, r2, #0x8000
+_0200211C:
+	mov r0, r5, lsl #1
+	tst r5, #0x80000000
+	mov r4, r4, lsl #1
+	orrne r4, r4, #1
+	bic r5, r0, #1
+	tst r6, #0x80000000
+	orrne r5, r5, #1
+	mov r1, r7, lsl #1
+	tst r7, #0x80000000
+	mov r6, r6, lsl #1
+	bic r7, r1, #1
+	ldr r2, [sp, #4]
+	mov r0, r4
+	mov r1, r5
+	mov r3, fp
+	orrne r6, r6, #1
+	bl UFixedPoint64CmpLt
+	cmp r0, #0
+	bne _02002188
+	mov r0, r5
+	sub r5, r5, fp
+	cmp r0, r5
+	ldr r0, [sp, #4]
+	mov r1, #1
+	sub r4, r4, r0
+	sublo r4, r4, #1
+	b _0200218C
+_02002188:
+	mov r1, #0
+_0200218C:
+	mov r0, sb, lsl #1
+	tst sb, #0x80000000
+	bic sb, r0, #1
+	ldr r0, [sp]
+	mov r8, r8, lsl #1
+	add r0, r0, #1
+	orrne r8, r8, #1
+	cmp r1, #0
+	orrne sb, sb, #1
+	str r0, [sp]
+	cmp r0, #0x40
+	blt _0200211C
+	stmia sl, {r8, sb}
+_020021C0:
+	add sp, sp, #8
+	ldmia sp!, {r3, r4, r5, r6, r7, r8, sb, sl, fp, pc}
+	arm_func_end UDivideFixedPoint64
+
+	arm_func_start AddFixedPoint64
+AddFixedPoint64: ; 0x020021C8
+	stmdb sp!, {r3, lr}
+	ldr ip, [r1, #4]
+	ldr lr, [r1]
+	ldr r1, [r2]
+	ldr r3, [r2, #4]
+	add r1, lr, r1
+	add r2, ip, r3
+	cmp r2, ip
+	addlo r1, r1, #1
+	stmia r0, {r1, r2}
+	ldmia sp!, {r3, pc}
+	arm_func_end AddFixedPoint64
+
+	arm_func_start ClampedLn
+ClampedLn: ; 0x020021F4
+	cmp r1, #1
+	movlt r1, #1
+	cmp r1, #0x800
+	ldrge r1, _02002220 ; =0x000007FF
+	ldr r2, _02002224 ; =NATURAL_LOG_VALUE_TABLE
+	mov r1, r1, lsl #1
+	ldrsh r2, [r2, r1]
+	mov r1, #0
+	mov r2, r2, lsl #4
+	stmia r0, {r1, r2}
+	bx lr
+	.align 2, 0
+_02002220: .word 0x000007FF
+_02002224: .word NATURAL_LOG_VALUE_TABLE
+	arm_func_end ClampedLn
+
+	arm_func_start sub_02002228
+sub_02002228: ; 0x02002228
+	bx lr
+	arm_func_end sub_02002228
+
+	arm_func_start GetRngSeed
+GetRngSeed: ; 0x0200222C
+	ldr r0, _02002238 ; =PRNG_SEQUENCE_NUM
+	ldrh r0, [r0]
+	bx lr
+	.align 2, 0
+_02002238: .word PRNG_SEQUENCE_NUM
+	arm_func_end GetRngSeed
+
+	arm_func_start SetRngSeed
+SetRngSeed: ; 0x0200223C
+	ldr r1, _02002248 ; =PRNG_SEQUENCE_NUM
+	strh r0, [r1]
+	bx lr
+	.align 2, 0
+_02002248: .word PRNG_SEQUENCE_NUM
+	arm_func_end SetRngSeed
diff --git a/include/main_02001A54.h b/include/main_02001A54.h
new file mode 100644
index 00000000..af2881b4
--- /dev/null
+++ b/include/main_02001A54.h
@@ -0,0 +1,8 @@
+#ifndef PMDSKY_MAIN_02001A54_H
+#define PMDSKY_MAIN_02001A54_H
+
+#include "util.h"
+
+s32 MultiplyByFixedPoint(s32 x, s32 y);
+
+#endif //PMDSKY_MAIN_02001A54_H
diff --git a/main.lsf b/main.lsf
index a60c43ac..3c17a76e 100644
--- a/main.lsf
+++ b/main.lsf
@@ -18,6 +18,8 @@ Static main
 	Object asm/main_020018A4.o
 	Object src/main_020018D0.o
 	Object asm/main_02001A30.o
+	Object src/main_02001A54.o
+	Object asm/main_02001AB0.o
 	Object src/main_0200224C.o
 	Object asm/main_020022C4.o
 	Object src/main_0200330C.o
diff --git a/src/main_02001A54.c b/src/main_02001A54.c
new file mode 100644
index 00000000..5a103714
--- /dev/null
+++ b/src/main_02001A54.c
@@ -0,0 +1,42 @@
+#include "main_02001A54.h"
+
+extern s32 UMultiplyByFixedPoint(s32, s32);
+
+s32 MultiplyByFixedPoint(s32 x, s32 y)
+{
+    s32 result;
+    bool8 xNeg;
+    bool8 yNeg;
+
+    // Same as checking if x < 0 and y < 0
+    if (x & 0x80000000) {
+        xNeg = TRUE;
+    } else {
+        xNeg = FALSE;
+    }
+    if (y & 0x80000000) {
+        yNeg = TRUE;
+    } else {
+        yNeg = FALSE;
+    }
+    
+    if (x == 0) {
+        return 0;
+    }
+    if (y == 0) {
+        return 0;
+    }
+    
+    if (xNeg) {
+        x = -x;
+    }
+    if (yNeg) {
+        y = -y;
+    }
+    
+    result = UMultiplyByFixedPoint(x, y);
+    if (xNeg != yNeg) {
+        result = -result;
+    }
+    return result;
+}