split random.s

1 files changed, 130 insertions, 0 deletions

diff --git a/asm/random.s b/asm/random.s
new file mode 100644
index 0000000..d09ba0a
--- /dev/null
+++ b/asm/random.s
@@ -0,0 +1,130 @@
+	.include "constants/gba_constants.inc"
+	.include "asm/macros.inc"
+
+	.syntax unified
+
+	.text
+
+	thumb_func_start SeedRng
+SeedRng:
+	push {r4,lr}
+	ldr r4, _08006170
+	ldrb r2, [r0]
+	ldrb r1, [r0, 0x1]
+	muls r2, r1
+	ldrb r3, [r0, 0x2]
+	ldrb r1, [r0, 0x3]
+	muls r1, r3
+	ldr r3, _08006174
+	adds r1, r3
+	adds r2, r1
+	ldrb r1, [r0, 0x4]
+	ldrb r0, [r0, 0x5]
+	muls r0, r1
+	adds r2, r0
+	str r2, [r4]
+	pop {r4}
+	pop {r0}
+	bx r0
+	.align 2, 0
+_08006170: .4byte gUnknown_203B07C
+_08006174: .4byte 0x0000d305
+	thumb_func_end SeedRng
+
+	thumb_func_start Random16
+Random16:
+	ldr r2, _08006188
+	ldr r1, [r2]
+	ldr r0, _0800618C
+	muls r0, r1
+	adds r0, 0x1
+	str r0, [r2]
+	asrs r0, 16
+	bx lr
+	.align 2, 0
+_08006188: .4byte gUnknown_203B07C
+_0800618C: .4byte 0x5d588b65
+	thumb_func_end Random16
+
+	thumb_func_start Random
+Random:
+	push {r4,lr}
+	bl Random16
+	adds r4, r0, 0
+	lsls r4, 16
+	asrs r4, 16
+	bl Random16
+	lsls r0, 16
+	asrs r0, 16
+	lsls r4, 16
+	orrs r4, r0
+	adds r0, r4, 0
+	pop {r4}
+	pop {r1}
+	bx r1
+	thumb_func_end Random
+
+	thumb_func_start RandomCapped
+RandomCapped:
+	push {r4,lr}
+	adds r4, r0, 0
+	bl Random
+	ldr r1, _080061C8
+	ands r0, r1
+	muls r0, r4
+	asrs r0, 16
+	ands r0, r1
+	pop {r4}
+	pop {r1}
+	bx r1
+	.align 2, 0
+_080061C8: .4byte 0x0000ffff
+	thumb_func_end RandomCapped
+
+	thumb_func_start RandomRange
+RandomRange:
+	push {r4,r5,lr}
+	adds r5, r0, 0
+	adds r4, r1, 0
+	cmp r5, r4
+	beq _080061EC
+	cmp r5, r4
+	blt _080061E4
+	subs r0, r5, r4
+	bl RandomCapped
+	adds r0, r4
+	b _080061EC
+_080061E4:
+	subs r0, r4, r5
+	bl RandomCapped
+	adds r0, r5
+_080061EC:
+	pop {r4,r5}
+	pop {r1}
+	bx r1
+	thumb_func_end RandomRange
+
+	thumb_func_start GetRngState
+GetRngState:
+	ldr r0, _080061FC
+	ldr r0, [r0]
+	bx lr
+	.align 2, 0
+_080061FC: .4byte gUnknown_203B07C
+	thumb_func_end GetRngState
+
+	thumb_func_start ReseedRng
+ReseedRng:
+	push {r4,lr}
+	ldr r4, _08006214
+	str r0, [r4]
+	bl Random
+	str r0, [r4]
+	pop {r4}
+	pop {r0}
+	bx r0
+	.align 2, 0
+_08006214: .4byte gUnknown_203B07C
+	thumb_func_end ReseedRng
+
+	.align 2, 0 @ Don't pad with nop.