diff --git a/ld/libfiles.ntsc-beta.inc b/ld/libfiles.ntsc-beta.inc
index ac55fc41b..b2e37e8a0 100644
--- a/ld/libfiles.ntsc-beta.inc
+++ b/ld/libfiles.ntsc-beta.inc
@@ -157,7 +157,7 @@
 	build/ROMID/lib/ultra/os/writebackdcache.o (section); \
 	build/ROMID/lib/ultra/libc/ll.o (section); \
 	build/ROMID/lib/ultra/libc/bzero.o (section); \
-	build/ROMID/lib/lib_4b170.o (section); \
+	build/ROMID/lib/ultra/libc/bcopy.o (section); \
 	build/ROMID/lib/ultra/os/virtualtophysical.o (section); \
 	build/ROMID/lib/ultra/io/spsetstat.o (section); \
 	build/ROMID/lib/ultra/io/spsetpc.o (section); \
diff --git a/ld/libfiles.ntsc-final.inc b/ld/libfiles.ntsc-final.inc
index 3538dfcee..5b5fbb24c 100644
--- a/ld/libfiles.ntsc-final.inc
+++ b/ld/libfiles.ntsc-final.inc
@@ -157,7 +157,7 @@
 	build/ROMID/lib/ultra/libc/ll.o (section); \
 	build/ROMID/lib/ultra/libc/bzero.o (section); \
 	build/ROMID/lib/ultra/os/getcause.o (section); \
-	build/ROMID/lib/lib_4b170.o (section); \
+	build/ROMID/lib/ultra/libc/bcopy.o (section); \
 	build/ROMID/lib/ultra/os/virtualtophysical.o (section); \
 	build/ROMID/lib/ultra/io/spsetstat.o (section); \
 	build/ROMID/lib/ultra/io/spsetpc.o (section); \
diff --git a/ld/libfiles.pal-final.inc b/ld/libfiles.pal-final.inc
index 27c3b6d3c..ba5dce7c4 100644
--- a/ld/libfiles.pal-final.inc
+++ b/ld/libfiles.pal-final.inc
@@ -156,7 +156,7 @@
 	build/ROMID/lib/ultra/os/writebackdcache.o (section); \
 	build/ROMID/lib/ultra/libc/bzero.o (section); \
 	build/ROMID/lib/ultra/os/getcause.o (section); \
-	build/ROMID/lib/lib_4b170.o (section); \
+	build/ROMID/lib/ultra/libc/bcopy.o (section); \
 	build/ROMID/lib/ultra/os/virtualtophysical.o (section); \
 	build/ROMID/lib/ultra/io/spsetstat.o (section); \
 	build/ROMID/lib/ultra/io/spsetpc.o (section); \
diff --git a/src/game/bg.c b/src/game/bg.c
index 77941e5a5..34e8226c7 100644
--- a/src/game/bg.c
+++ b/src/game/bg.c
@@ -38,7 +38,6 @@
 #include "lib/lib_159b0.h"
 #include "lib/lib_16110.h"
 #include "lib/lib_2f490.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/game/bossfile.c b/src/game/bossfile.c
index 2fd46a41a..b96ca4169 100644
--- a/src/game/bossfile.c
+++ b/src/game/bossfile.c
@@ -18,7 +18,6 @@
 #include "lib/lib_0bfb0.h"
 #include "lib/snd.h"
 #include "lib/lib_126b0.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/game/filelist.c b/src/game/filelist.c
index eaf7d8549..699776ff2 100644
--- a/src/game/filelist.c
+++ b/src/game/filelist.c
@@ -18,7 +18,6 @@
 #include "lib/lib_0bfb0.h"
 #include "lib/snd.h"
 #include "lib/lib_126b0.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/game/game_173520.c b/src/game/game_173520.c
index ffc136bf9..49aba499f 100644
--- a/src/game/game_173520.c
+++ b/src/game/game_173520.c
@@ -7,7 +7,6 @@
 #include "lib/dma.h"
 #include "lib/main.h"
 #include "lib/memory.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/game/gamefile.c b/src/game/gamefile.c
index e9b3bfac1..5972bfaa5 100644
--- a/src/game/gamefile.c
+++ b/src/game/gamefile.c
@@ -17,7 +17,6 @@
 #include "lib/lib_0bfb0.h"
 #include "lib/snd.h"
 #include "lib/lib_126b0.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/game/texdecompress.c b/src/game/texdecompress.c
index 7db90d969..6c6284cf7 100644
--- a/src/game/texdecompress.c
+++ b/src/game/texdecompress.c
@@ -7,7 +7,6 @@
 #include "lib/dma.h"
 #include "lib/main.h"
 #include "lib/memory.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/include/lib/lib_4b170.h b/src/include/lib/lib_4b170.h
deleted file mode 100644
index 7252910a2..000000000
--- a/src/include/lib/lib_4b170.h
+++ /dev/null
@@ -1,7 +0,0 @@
-#ifndef _IN_LIB_LIB_4B170_H
-#define _IN_LIB_LIB_4B170_H
-#include <ultra64.h>
-#include "data.h"
-#include "types.h"
-
-#endif
diff --git a/src/lib/lib_09660.c b/src/lib/lib_09660.c
index 97ecd4c8b..1c6c8bef5 100644
--- a/src/lib/lib_09660.c
+++ b/src/lib/lib_09660.c
@@ -10,7 +10,6 @@
 #include "lib/memory.h"
 #include "lib/lib_159b0.h"
 #include "lib/lib_30ce0.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_09a80.c b/src/lib/lib_09a80.c
index 8e32bda23..08f291a2c 100644
--- a/src/lib/lib_09a80.c
+++ b/src/lib/lib_09a80.c
@@ -11,7 +11,6 @@
 #include "lib/memory.h"
 #include "lib/lib_159b0.h"
 #include "lib/lib_30ce0.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_233c0.c b/src/lib/lib_233c0.c
index 02bd81a10..b99c4897d 100644
--- a/src/lib/lib_233c0.c
+++ b/src/lib/lib_233c0.c
@@ -10,7 +10,6 @@
 #include "lib/lib_233c0.h"
 #include "lib/lib_2f490.h"
 #include "lib/libc/ll.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_24e40.c b/src/lib/lib_24e40.c
index 8a813bb66..50faedd8f 100644
--- a/src/lib/lib_24e40.c
+++ b/src/lib/lib_24e40.c
@@ -13,7 +13,6 @@
 #include "lib/lib_24e40.h"
 #include "lib/lib_2f490.h"
 #include "lib/libc/ll.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_3c890.c b/src/lib/lib_3c890.c
index 7bc585a71..6d42d9466 100644
--- a/src/lib/lib_3c890.c
+++ b/src/lib/lib_3c890.c
@@ -4,7 +4,6 @@
 #include "lib/lib_30ce0.h"
 #include "lib/lib_3c4d0.h"
 #include "lib/lib_3e730.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_3e730.c b/src/lib/lib_3e730.c
index db4c50b90..9bb41eef3 100644
--- a/src/lib/lib_3e730.c
+++ b/src/lib/lib_3e730.c
@@ -11,7 +11,6 @@
 #include "lib/lib_46650.h"
 #include "lib/lib_47550.h"
 #include "lib/libc/ll.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_3e8c0.c b/src/lib/lib_3e8c0.c
index c8a753796..a2a4a4617 100644
--- a/src/lib/lib_3e8c0.c
+++ b/src/lib/lib_3e8c0.c
@@ -12,7 +12,6 @@
 #include "lib/lib_46650.h"
 #include "lib/lib_47550.h"
 #include "lib/libc/ll.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_3f8a0.c b/src/lib/lib_3f8a0.c
index ed8009801..cb5a6e120 100644
--- a/src/lib/lib_3f8a0.c
+++ b/src/lib/lib_3f8a0.c
@@ -12,7 +12,6 @@
 #include "lib/lib_46650.h"
 #include "lib/lib_47550.h"
 #include "lib/libc/ll.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_43dd0.c b/src/lib/lib_43dd0.c
index f81d1532d..e71af9ae1 100644
--- a/src/lib/lib_43dd0.c
+++ b/src/lib/lib_43dd0.c
@@ -6,7 +6,6 @@
 #include "lib/lib_43dd0.h"
 #include "lib/lib_461c0.h"
 #include "lib/libc/ll.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_44f60.c b/src/lib/lib_44f60.c
index 0dc74291b..13dda50ff 100644
--- a/src/lib/lib_44f60.c
+++ b/src/lib/lib_44f60.c
@@ -4,7 +4,6 @@
 #include "lib/lib_3a100.h"
 #include "lib/lib_44f60.h"
 #include "lib/lib_47a90.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/lib_4b170.c b/src/lib/lib_4b170.c
deleted file mode 100644
index ea2b60a33..000000000
--- a/src/lib/lib_4b170.c
+++ /dev/null
@@ -1,228 +0,0 @@
-#include <ultra64.h>
-#include "constants.h"
-#include "bss.h"
-#include "data.h"
-#include "types.h"
-
-GLOBAL_ASM(
-glabel bcopy
-/*    4b170:	10c0001a */ 	beqz	$a2,.L0004b1dc
-/*    4b174:	00a03825 */ 	or	$a3,$a1,$zero
-/*    4b178:	10850018 */ 	beq	$a0,$a1,.L0004b1dc
-/*    4b17c:	00a4082a */ 	slt	$at,$a1,$a0
-/*    4b180:	54200008 */ 	bnezl	$at,.L0004b1a4
-/*    4b184:	28c10010 */ 	slti	$at,$a2,0x10
-/*    4b188:	00861020 */ 	add	$v0,$a0,$a2
-/*    4b18c:	00a2082a */ 	slt	$at,$a1,$v0
-/*    4b190:	50200004 */ 	beqzl	$at,.L0004b1a4
-/*    4b194:	28c10010 */ 	slti	$at,$a2,0x10
-/*    4b198:	1000005b */ 	b	.L0004b308
-/*    4b19c:	28c10010 */ 	slti	$at,$a2,0x10
-/*    4b1a0:	28c10010 */ 	slti	$at,$a2,0x10
-.L0004b1a4:
-/*    4b1a4:	14200005 */ 	bnez	$at,.L0004b1bc
-/*    4b1a8:	00000000 */ 	nop
-/*    4b1ac:	30820003 */ 	andi	$v0,$a0,0x3
-/*    4b1b0:	30a30003 */ 	andi	$v1,$a1,0x3
-/*    4b1b4:	1043000b */ 	beq	$v0,$v1,.L0004b1e4
-/*    4b1b8:	00000000 */ 	nop
-.L0004b1bc:
-/*    4b1bc:	10c00007 */ 	beqz	$a2,.L0004b1dc
-/*    4b1c0:	00000000 */ 	nop
-/*    4b1c4:	00861821 */ 	addu	$v1,$a0,$a2
-.L0004b1c8:
-/*    4b1c8:	80820000 */ 	lb	$v0,0x0($a0)
-/*    4b1cc:	24840001 */ 	addiu	$a0,$a0,0x1
-/*    4b1d0:	24a50001 */ 	addiu	$a1,$a1,0x1
-/*    4b1d4:	1483fffc */ 	bne	$a0,$v1,.L0004b1c8
-/*    4b1d8:	a0a2ffff */ 	sb	$v0,-0x1($a1)
-.L0004b1dc:
-/*    4b1dc:	03e00008 */ 	jr	$ra
-/*    4b1e0:	00e01025 */ 	or	$v0,$a3,$zero
-.L0004b1e4:
-/*    4b1e4:	10400018 */ 	beqz	$v0,.L0004b248
-/*    4b1e8:	24010001 */ 	addiu	$at,$zero,0x1
-/*    4b1ec:	1041000f */ 	beq	$v0,$at,.L0004b22c
-/*    4b1f0:	24010002 */ 	addiu	$at,$zero,0x2
-/*    4b1f4:	50410008 */ 	beql	$v0,$at,.L0004b218
-/*    4b1f8:	84820000 */ 	lh	$v0,0x0($a0)
-/*    4b1fc:	80820000 */ 	lb	$v0,0x0($a0)
-/*    4b200:	24840001 */ 	addiu	$a0,$a0,0x1
-/*    4b204:	24a50001 */ 	addiu	$a1,$a1,0x1
-/*    4b208:	24c6ffff */ 	addiu	$a2,$a2,-1
-/*    4b20c:	1000000e */ 	b	.L0004b248
-/*    4b210:	a0a2ffff */ 	sb	$v0,-0x1($a1)
-/*    4b214:	84820000 */ 	lh	$v0,0x0($a0)
-.L0004b218:
-/*    4b218:	24840002 */ 	addiu	$a0,$a0,0x2
-/*    4b21c:	24a50002 */ 	addiu	$a1,$a1,0x2
-/*    4b220:	24c6fffe */ 	addiu	$a2,$a2,-2
-/*    4b224:	10000008 */ 	b	.L0004b248
-/*    4b228:	a4a2fffe */ 	sh	$v0,-0x2($a1)
-.L0004b22c:
-/*    4b22c:	80820000 */ 	lb	$v0,0x0($a0)
-/*    4b230:	84830001 */ 	lh	$v1,0x1($a0)
-/*    4b234:	24840003 */ 	addiu	$a0,$a0,0x3
-/*    4b238:	24a50003 */ 	addiu	$a1,$a1,0x3
-/*    4b23c:	24c6fffd */ 	addiu	$a2,$a2,-3
-/*    4b240:	a0a2fffd */ 	sb	$v0,-0x3($a1)
-/*    4b244:	a4a3fffe */ 	sh	$v1,-0x2($a1)
-.L0004b248:
-/*    4b248:	28c10020 */ 	slti	$at,$a2,0x20
-/*    4b24c:	54200016 */ 	bnezl	$at,.L0004b2a8
-/*    4b250:	28c10010 */ 	slti	$at,$a2,0x10
-/*    4b254:	8c820000 */ 	lw	$v0,0x0($a0)
-/*    4b258:	8c830004 */ 	lw	$v1,0x4($a0)
-/*    4b25c:	8c880008 */ 	lw	$t0,0x8($a0)
-/*    4b260:	8c89000c */ 	lw	$t1,0xc($a0)
-/*    4b264:	8c8a0010 */ 	lw	$t2,0x10($a0)
-/*    4b268:	8c8b0014 */ 	lw	$t3,0x14($a0)
-/*    4b26c:	8c8c0018 */ 	lw	$t4,0x18($a0)
-/*    4b270:	8c8d001c */ 	lw	$t5,0x1c($a0)
-/*    4b274:	24840020 */ 	addiu	$a0,$a0,0x20
-/*    4b278:	24a50020 */ 	addiu	$a1,$a1,0x20
-/*    4b27c:	24c6ffe0 */ 	addiu	$a2,$a2,-32
-/*    4b280:	aca2ffe0 */ 	sw	$v0,-0x20($a1)
-/*    4b284:	aca3ffe4 */ 	sw	$v1,-0x1c($a1)
-/*    4b288:	aca8ffe8 */ 	sw	$t0,-0x18($a1)
-/*    4b28c:	aca9ffec */ 	sw	$t1,-0x14($a1)
-/*    4b290:	acaafff0 */ 	sw	$t2,-0x10($a1)
-/*    4b294:	acabfff4 */ 	sw	$t3,-0xc($a1)
-/*    4b298:	acacfff8 */ 	sw	$t4,-0x8($a1)
-/*    4b29c:	1000ffea */ 	b	.L0004b248
-/*    4b2a0:	acadfffc */ 	sw	$t5,-0x4($a1)
-.L0004b2a4:
-/*    4b2a4:	28c10010 */ 	slti	$at,$a2,0x10
-.L0004b2a8:
-/*    4b2a8:	5420000e */ 	bnezl	$at,.L0004b2e4
-/*    4b2ac:	28c10004 */ 	slti	$at,$a2,0x4
-/*    4b2b0:	8c820000 */ 	lw	$v0,0x0($a0)
-/*    4b2b4:	8c830004 */ 	lw	$v1,0x4($a0)
-/*    4b2b8:	8c880008 */ 	lw	$t0,0x8($a0)
-/*    4b2bc:	8c89000c */ 	lw	$t1,0xc($a0)
-/*    4b2c0:	24840010 */ 	addiu	$a0,$a0,0x10
-/*    4b2c4:	24a50010 */ 	addiu	$a1,$a1,0x10
-/*    4b2c8:	24c6fff0 */ 	addiu	$a2,$a2,-16
-/*    4b2cc:	aca2fff0 */ 	sw	$v0,-0x10($a1)
-/*    4b2d0:	aca3fff4 */ 	sw	$v1,-0xc($a1)
-/*    4b2d4:	aca8fff8 */ 	sw	$t0,-0x8($a1)
-/*    4b2d8:	1000fff2 */ 	b	.L0004b2a4
-/*    4b2dc:	aca9fffc */ 	sw	$t1,-0x4($a1)
-.L0004b2e0:
-/*    4b2e0:	28c10004 */ 	slti	$at,$a2,0x4
-.L0004b2e4:
-/*    4b2e4:	1420ffb5 */ 	bnez	$at,.L0004b1bc
-/*    4b2e8:	00000000 */ 	nop
-/*    4b2ec:	8c820000 */ 	lw	$v0,0x0($a0)
-/*    4b2f0:	24840004 */ 	addiu	$a0,$a0,0x4
-/*    4b2f4:	24a50004 */ 	addiu	$a1,$a1,0x4
-/*    4b2f8:	24c6fffc */ 	addiu	$a2,$a2,-4
-/*    4b2fc:	1000fff8 */ 	b	.L0004b2e0
-/*    4b300:	aca2fffc */ 	sw	$v0,-0x4($a1)
-/*    4b304:	28c10010 */ 	slti	$at,$a2,0x10
-.L0004b308:
-/*    4b308:	00862020 */ 	add	$a0,$a0,$a2
-/*    4b30c:	14200005 */ 	bnez	$at,.L0004b324
-/*    4b310:	00a62820 */ 	add	$a1,$a1,$a2
-/*    4b314:	30820003 */ 	andi	$v0,$a0,0x3
-/*    4b318:	30a30003 */ 	andi	$v1,$a1,0x3
-/*    4b31c:	1043000d */ 	beq	$v0,$v1,.L0004b354
-/*    4b320:	00000000 */ 	nop
-.L0004b324:
-/*    4b324:	10c0ffad */ 	beqz	$a2,.L0004b1dc
-/*    4b328:	00000000 */ 	nop
-/*    4b32c:	2484ffff */ 	addiu	$a0,$a0,-1
-/*    4b330:	24a5ffff */ 	addiu	$a1,$a1,-1
-/*    4b334:	00861823 */ 	subu	$v1,$a0,$a2
-.L0004b338:
-/*    4b338:	80820000 */ 	lb	$v0,0x0($a0)
-/*    4b33c:	2484ffff */ 	addiu	$a0,$a0,-1
-/*    4b340:	24a5ffff */ 	addiu	$a1,$a1,-1
-/*    4b344:	1483fffc */ 	bne	$a0,$v1,.L0004b338
-/*    4b348:	a0a20001 */ 	sb	$v0,0x1($a1)
-/*    4b34c:	03e00008 */ 	jr	$ra
-/*    4b350:	00e01025 */ 	or	$v0,$a3,$zero
-.L0004b354:
-/*    4b354:	10400018 */ 	beqz	$v0,.L0004b3b8
-/*    4b358:	24010003 */ 	addiu	$at,$zero,0x3
-/*    4b35c:	1041000f */ 	beq	$v0,$at,.L0004b39c
-/*    4b360:	24010002 */ 	addiu	$at,$zero,0x2
-/*    4b364:	50410008 */ 	beql	$v0,$at,.L0004b388
-/*    4b368:	8482fffe */ 	lh	$v0,-0x2($a0)
-/*    4b36c:	8082ffff */ 	lb	$v0,-0x1($a0)
-/*    4b370:	2484ffff */ 	addiu	$a0,$a0,-1
-/*    4b374:	24a5ffff */ 	addiu	$a1,$a1,-1
-/*    4b378:	24c6ffff */ 	addiu	$a2,$a2,-1
-/*    4b37c:	1000000e */ 	b	.L0004b3b8
-/*    4b380:	a0a20000 */ 	sb	$v0,0x0($a1)
-/*    4b384:	8482fffe */ 	lh	$v0,-0x2($a0)
-.L0004b388:
-/*    4b388:	2484fffe */ 	addiu	$a0,$a0,-2
-/*    4b38c:	24a5fffe */ 	addiu	$a1,$a1,-2
-/*    4b390:	24c6fffe */ 	addiu	$a2,$a2,-2
-/*    4b394:	10000008 */ 	b	.L0004b3b8
-/*    4b398:	a4a20000 */ 	sh	$v0,0x0($a1)
-.L0004b39c:
-/*    4b39c:	8082ffff */ 	lb	$v0,-0x1($a0)
-/*    4b3a0:	8483fffd */ 	lh	$v1,-0x3($a0)
-/*    4b3a4:	2484fffd */ 	addiu	$a0,$a0,-3
-/*    4b3a8:	24a5fffd */ 	addiu	$a1,$a1,-3
-/*    4b3ac:	24c6fffd */ 	addiu	$a2,$a2,-3
-/*    4b3b0:	a0a20002 */ 	sb	$v0,0x2($a1)
-/*    4b3b4:	a4a30000 */ 	sh	$v1,0x0($a1)
-.L0004b3b8:
-/*    4b3b8:	28c10020 */ 	slti	$at,$a2,0x20
-/*    4b3bc:	54200016 */ 	bnezl	$at,.L0004b418
-/*    4b3c0:	28c10010 */ 	slti	$at,$a2,0x10
-/*    4b3c4:	8c82fffc */ 	lw	$v0,-0x4($a0)
-/*    4b3c8:	8c83fff8 */ 	lw	$v1,-0x8($a0)
-/*    4b3cc:	8c88fff4 */ 	lw	$t0,-0xc($a0)
-/*    4b3d0:	8c89fff0 */ 	lw	$t1,-0x10($a0)
-/*    4b3d4:	8c8affec */ 	lw	$t2,-0x14($a0)
-/*    4b3d8:	8c8bffe8 */ 	lw	$t3,-0x18($a0)
-/*    4b3dc:	8c8cffe4 */ 	lw	$t4,-0x1c($a0)
-/*    4b3e0:	8c8dffe0 */ 	lw	$t5,-0x20($a0)
-/*    4b3e4:	2484ffe0 */ 	addiu	$a0,$a0,-32
-/*    4b3e8:	24a5ffe0 */ 	addiu	$a1,$a1,-32
-/*    4b3ec:	24c6ffe0 */ 	addiu	$a2,$a2,-32
-/*    4b3f0:	aca2001c */ 	sw	$v0,0x1c($a1)
-/*    4b3f4:	aca30018 */ 	sw	$v1,0x18($a1)
-/*    4b3f8:	aca80014 */ 	sw	$t0,0x14($a1)
-/*    4b3fc:	aca90010 */ 	sw	$t1,0x10($a1)
-/*    4b400:	acaa000c */ 	sw	$t2,0xc($a1)
-/*    4b404:	acab0008 */ 	sw	$t3,0x8($a1)
-/*    4b408:	acac0004 */ 	sw	$t4,0x4($a1)
-/*    4b40c:	1000ffea */ 	b	.L0004b3b8
-/*    4b410:	acad0000 */ 	sw	$t5,0x0($a1)
-.L0004b414:
-/*    4b414:	28c10010 */ 	slti	$at,$a2,0x10
-.L0004b418:
-/*    4b418:	5420000e */ 	bnezl	$at,.L0004b454
-/*    4b41c:	28c10004 */ 	slti	$at,$a2,0x4
-/*    4b420:	8c82fffc */ 	lw	$v0,-0x4($a0)
-/*    4b424:	8c83fff8 */ 	lw	$v1,-0x8($a0)
-/*    4b428:	8c88fff4 */ 	lw	$t0,-0xc($a0)
-/*    4b42c:	8c89fff0 */ 	lw	$t1,-0x10($a0)
-/*    4b430:	2484fff0 */ 	addiu	$a0,$a0,-16
-/*    4b434:	24a5fff0 */ 	addiu	$a1,$a1,-16
-/*    4b438:	24c6fff0 */ 	addiu	$a2,$a2,-16
-/*    4b43c:	aca2000c */ 	sw	$v0,0xc($a1)
-/*    4b440:	aca30008 */ 	sw	$v1,0x8($a1)
-/*    4b444:	aca80004 */ 	sw	$t0,0x4($a1)
-/*    4b448:	1000fff2 */ 	b	.L0004b414
-/*    4b44c:	aca90000 */ 	sw	$t1,0x0($a1)
-.L0004b450:
-/*    4b450:	28c10004 */ 	slti	$at,$a2,0x4
-.L0004b454:
-/*    4b454:	1420ffb3 */ 	bnez	$at,.L0004b324
-/*    4b458:	00000000 */ 	nop
-/*    4b45c:	8c82fffc */ 	lw	$v0,-0x4($a0)
-/*    4b460:	2484fffc */ 	addiu	$a0,$a0,-4
-/*    4b464:	24a5fffc */ 	addiu	$a1,$a1,-4
-/*    4b468:	24c6fffc */ 	addiu	$a2,$a2,-4
-/*    4b46c:	1000fff8 */ 	b	.L0004b450
-/*    4b470:	aca20000 */ 	sw	$v0,0x0($a1)
-/*    4b474:	00000000 */ 	nop
-/*    4b478:	00000000 */ 	nop
-/*    4b47c:	00000000 */ 	nop
-);
diff --git a/src/lib/lib_51570.c b/src/lib/lib_51570.c
index 44f008d4f..7d365bb62 100644
--- a/src/lib/lib_51570.c
+++ b/src/lib/lib_51570.c
@@ -2,7 +2,6 @@
 #include "libultra_internal.h"
 #include "constants.h"
 #include "bss.h"
-#include "lib/lib_4b170.h"
 #include "lib/lib_4e090.h"
 #include "data.h"
 #include "types.h"
diff --git a/src/lib/ultra/audio/event.c b/src/lib/ultra/audio/event.c
index 788060974..0da6fe4c8 100644
--- a/src/lib/ultra/audio/event.c
+++ b/src/lib/ultra/audio/event.c
@@ -4,7 +4,6 @@
 #include "lib/lib_30ce0.h"
 #include "lib/lib_3c4d0.h"
 #include "lib/lib_3e730.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/ultra/io/contpfs.c b/src/lib/ultra/io/contpfs.c
index 09875bce6..c3513cf1c 100644
--- a/src/lib/ultra/io/contpfs.c
+++ b/src/lib/ultra/io/contpfs.c
@@ -2,7 +2,6 @@
 #include "libultra_internal.h"
 #include "constants.h"
 #include "bss.h"
-#include "lib/lib_4b170.h"
 #include "lib/lib_4e090.h"
 #include "data.h"
 #include "types.h"
diff --git a/src/lib/ultra/io/pfsallocatefile.c b/src/lib/ultra/io/pfsallocatefile.c
index 8fbe7fe8d..f8d48d416 100644
--- a/src/lib/ultra/io/pfsallocatefile.c
+++ b/src/lib/ultra/io/pfsallocatefile.c
@@ -2,7 +2,6 @@
 #include "libultra_internal.h"
 #include "constants.h"
 #include "bss.h"
-#include "lib/lib_4b170.h"
 #include "data.h"
 #include "types.h"
 
diff --git a/src/lib/ultra/io/pfsfilestate.c b/src/lib/ultra/io/pfsfilestate.c
index 8ebe8df34..1c166b25c 100644
--- a/src/lib/ultra/io/pfsfilestate.c
+++ b/src/lib/ultra/io/pfsfilestate.c
@@ -2,7 +2,6 @@
 #include "libultra_internal.h"
 #include "constants.h"
 #include "bss.h"
-#include "lib/lib_4b170.h"
 #include "lib/lib_4e090.h"
 #include "data.h"
 #include "types.h"
diff --git a/src/lib/ultra/io/pfsinitpak.c b/src/lib/ultra/io/pfsinitpak.c
index 372a01d07..ce4e8ac63 100644
--- a/src/lib/ultra/io/pfsinitpak.c
+++ b/src/lib/ultra/io/pfsinitpak.c
@@ -3,7 +3,6 @@
 #include "libultra_internal.h"
 #include "constants.h"
 #include "bss.h"
-#include "lib/lib_4b170.h"
 #include "lib/lib_4e090.h"
 #include "data.h"
 #include "types.h"
diff --git a/src/lib/ultra/io/pfsresizefile.c b/src/lib/ultra/io/pfsresizefile.c
index 8aa37bce7..db24195d7 100644
--- a/src/lib/ultra/io/pfsresizefile.c
+++ b/src/lib/ultra/io/pfsresizefile.c
@@ -2,7 +2,6 @@
 #include "libultra_internal.h"
 #include "constants.h"
 #include "bss.h"
-#include "lib/lib_4b170.h"
 #include "lib/lib_4e090.h"
 #include "data.h"
 #include "types.h"
diff --git a/src/lib/ultra/libc/bcopy.s b/src/lib/ultra/libc/bcopy.s
new file mode 100644
index 000000000..a16d4c5cb
--- /dev/null
+++ b/src/lib/ultra/libc/bcopy.s
@@ -0,0 +1,223 @@
+#include "macros.inc"
+.set noat
+.set noreorder
+
+.section .text
+
+glabel bcopy
+	beqz  $a2, .L0004b1dc
+	move  $a3, $a1
+	beq   $a0, $a1, .L0004b1dc
+	slt   $at, $a1, $a0
+	bnezl $at, .L0004b1a4
+	slti  $at, $a2, 0x10
+	add   $v0, $a0, $a2
+	slt   $at, $a1, $v0
+	beqzl $at, .L0004b1a4
+	slti  $at, $a2, 0x10
+	b     .L0004b308
+	slti  $at, $a2, 0x10
+	slti  $at, $a2, 0x10
+.L0004b1a4:
+	bnez  $at, .L0004b1bc
+ 	nop
+	andi  $v0, $a0, 0x3
+	andi  $v1, $a1, 0x3
+	beq   $v0, $v1, .L0004b1e4
+ 	nop
+.L0004b1bc:
+	beqz  $a2, .L0004b1dc
+ 	nop
+	addu  $v1, $a0, $a2
+.L0004b1c8:
+	lb    $v0, 0x0($a0)
+	addiu $a0, $a0, 0x1
+	addiu $a1, $a1, 0x1
+	bne   $a0, $v1, .L0004b1c8
+	sb    $v0, -0x1($a1)
+.L0004b1dc:
+	jr    $ra
+	move  $v0, $a3
+.L0004b1e4:
+	beqz  $v0, .L0004b248
+	addiu $at, $zero, 0x1
+	beq   $v0, $at, .L0004b22c
+	addiu $at, $zero, 0x2
+	beql  $v0, $at, .L0004b218
+	lh    $v0, 0x0($a0)
+	lb    $v0, 0x0($a0)
+	addiu $a0, $a0, 0x1
+	addiu $a1, $a1, 0x1
+	addiu $a2, $a2, -1
+	b     .L0004b248
+	sb    $v0, -0x1($a1)
+	lh    $v0, 0x0($a0)
+.L0004b218:
+	addiu $a0, $a0, 0x2
+	addiu $a1, $a1, 0x2
+	addiu $a2, $a2, -2
+	b     .L0004b248
+	sh    $v0, -0x2($a1)
+.L0004b22c:
+	lb    $v0, 0x0($a0)
+	lh    $v1, 0x1($a0)
+	addiu $a0, $a0, 0x3
+	addiu $a1, $a1, 0x3
+	addiu $a2, $a2, -3
+	sb    $v0, -0x3($a1)
+	sh    $v1, -0x2($a1)
+.L0004b248:
+	slti  $at, $a2, 0x20
+	bnezl $at, .L0004b2a8
+	slti  $at, $a2, 0x10
+	lw    $v0, 0x0($a0)
+	lw    $v1, 0x4($a0)
+	lw    $t0, 0x8($a0)
+	lw    $t1, 0xc($a0)
+	lw    $t2, 0x10($a0)
+	lw    $t3, 0x14($a0)
+	lw    $t4, 0x18($a0)
+	lw    $t5, 0x1c($a0)
+	addiu $a0, $a0, 0x20
+	addiu $a1, $a1, 0x20
+	addiu $a2, $a2, -32
+	sw    $v0, -0x20($a1)
+	sw    $v1, -0x1c($a1)
+	sw    $t0, -0x18($a1)
+	sw    $t1, -0x14($a1)
+	sw    $t2, -0x10($a1)
+	sw    $t3, -0xc($a1)
+	sw    $t4, -0x8($a1)
+	b     .L0004b248
+	sw    $t5, -0x4($a1)
+.L0004b2a4:
+	slti  $at, $a2, 0x10
+.L0004b2a8:
+	bnezl $at, .L0004b2e4
+	slti  $at, $a2, 0x4
+	lw    $v0, 0x0($a0)
+	lw    $v1, 0x4($a0)
+	lw    $t0, 0x8($a0)
+	lw    $t1, 0xc($a0)
+	addiu $a0, $a0, 0x10
+	addiu $a1, $a1, 0x10
+	addiu $a2, $a2, -16
+	sw    $v0, -0x10($a1)
+	sw    $v1, -0xc($a1)
+	sw    $t0, -0x8($a1)
+	b     .L0004b2a4
+	sw    $t1, -0x4($a1)
+.L0004b2e0:
+	slti  $at, $a2, 0x4
+.L0004b2e4:
+	bnez  $at, .L0004b1bc
+ 	nop
+	lw    $v0, 0x0($a0)
+	addiu $a0, $a0, 0x4
+	addiu $a1, $a1, 0x4
+	addiu $a2, $a2, -4
+	b     .L0004b2e0
+	sw    $v0, -0x4($a1)
+	slti  $at, $a2, 0x10
+.L0004b308:
+	add   $a0, $a0, $a2
+	bnez  $at, .L0004b324
+	add   $a1, $a1, $a2
+	andi  $v0, $a0, 0x3
+	andi  $v1, $a1, 0x3
+	beq   $v0, $v1, .L0004b354
+ 	nop
+.L0004b324:
+	beqz  $a2, .L0004b1dc
+ 	nop
+	addiu $a0, $a0, -1
+	addiu $a1, $a1, -1
+	subu  $v1, $a0, $a2
+.L0004b338:
+	lb    $v0, 0x0($a0)
+	addiu $a0, $a0, -1
+	addiu $a1, $a1, -1
+	bne   $a0, $v1, .L0004b338
+	sb    $v0, 0x1($a1)
+	jr    $ra
+	move  $v0, $a3
+.L0004b354:
+	beqz  $v0, .L0004b3b8
+	addiu $at, $zero, 0x3
+	beq   $v0, $at, .L0004b39c
+	addiu $at, $zero, 0x2
+	beql  $v0, $at, .L0004b388
+	lh    $v0, -0x2($a0)
+	lb    $v0, -0x1($a0)
+	addiu $a0, $a0, -1
+	addiu $a1, $a1, -1
+	addiu $a2, $a2, -1
+	b     .L0004b3b8
+	sb    $v0, 0x0($a1)
+	lh    $v0, -0x2($a0)
+.L0004b388:
+	addiu $a0, $a0, -2
+	addiu $a1, $a1, -2
+	addiu $a2, $a2, -2
+	b     .L0004b3b8
+	sh    $v0, 0x0($a1)
+.L0004b39c:
+	lb    $v0, -0x1($a0)
+	lh    $v1, -0x3($a0)
+	addiu $a0, $a0, -3
+	addiu $a1, $a1, -3
+	addiu $a2, $a2, -3
+	sb    $v0, 0x2($a1)
+	sh    $v1, 0x0($a1)
+.L0004b3b8:
+	slti  $at, $a2, 0x20
+	bnezl $at, .L0004b418
+	slti  $at, $a2, 0x10
+	lw    $v0, -0x4($a0)
+	lw    $v1, -0x8($a0)
+	lw    $t0, -0xc($a0)
+	lw    $t1, -0x10($a0)
+	lw    $t2, -0x14($a0)
+	lw    $t3, -0x18($a0)
+	lw    $t4, -0x1c($a0)
+	lw    $t5, -0x20($a0)
+	addiu $a0, $a0, -32
+	addiu $a1, $a1, -32
+	addiu $a2, $a2, -32
+	sw    $v0, 0x1c($a1)
+	sw    $v1, 0x18($a1)
+	sw    $t0, 0x14($a1)
+	sw    $t1, 0x10($a1)
+	sw    $t2, 0xc($a1)
+	sw    $t3, 0x8($a1)
+	sw    $t4, 0x4($a1)
+	b     .L0004b3b8
+	sw    $t5, 0x0($a1)
+.L0004b414:
+	slti  $at, $a2, 0x10
+.L0004b418:
+	bnezl $at, .L0004b454
+	slti  $at, $a2, 0x4
+	lw    $v0, -0x4($a0)
+	lw    $v1, -0x8($a0)
+	lw    $t0, -0xc($a0)
+	lw    $t1, -0x10($a0)
+	addiu $a0, $a0, -16
+	addiu $a1, $a1, -16
+	addiu $a2, $a2, -16
+	sw    $v0, 0xc($a1)
+	sw    $v1, 0x8($a1)
+	sw    $t0, 0x4($a1)
+	b     .L0004b414
+	sw    $t1, 0x0($a1)
+.L0004b450:
+	slti  $at, $a2, 0x4
+.L0004b454:
+	bnez  $at, .L0004b324
+ 	nop
+	lw    $v0, -0x4($a0)
+	addiu $a0, $a0, -4
+	addiu $a1, $a1, -4
+	addiu $a2, $a2, -4
+	b     .L0004b450
+	sw    $v0, 0x0($a1)