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authorAtsushi Nemoto <anemo@mba.ocn.ne.jp>2006-12-03 16:42:59 +0100
committerRalf Baechle <ralf@linux-mips.org>2006-12-04 23:43:13 +0100
commit0bcdda0f3a87ed684d46841b6069409e39c4af65 (patch)
tree52df8fc8d148b98188c09152bcf6e55c55a98c2a /arch
parent[MIPS] SWARM: Fix a typo in #error directives (diff)
downloadlinux-0bcdda0f3a87ed684d46841b6069409e39c4af65.tar.xz
linux-0bcdda0f3a87ed684d46841b6069409e39c4af65.zip
[MIPS] Unify csum_partial.S
The 32-bit version and 64-bit version are almost equal. Unify them. This makes further improvements (for example, copying with parallel, supporting PREFETCH, etc.) easier. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/mips/lib-32/Makefile2
-rw-r--r--arch/mips/lib-32/csum_partial.S240
-rw-r--r--arch/mips/lib-64/Makefile2
-rw-r--r--arch/mips/lib-64/csum_partial.S242
-rw-r--r--arch/mips/lib/Makefile4
-rw-r--r--arch/mips/lib/csum_partial.S258
6 files changed, 262 insertions, 486 deletions
diff --git a/arch/mips/lib-32/Makefile b/arch/mips/lib-32/Makefile
index ad285786e74b..dcd4d2ed2ac4 100644
--- a/arch/mips/lib-32/Makefile
+++ b/arch/mips/lib-32/Makefile
@@ -2,7 +2,7 @@
# Makefile for MIPS-specific library files..
#
-lib-y += csum_partial.o memset.o watch.o
+lib-y += memset.o watch.o
obj-$(CONFIG_CPU_MIPS32) += dump_tlb.o
obj-$(CONFIG_CPU_MIPS64) += dump_tlb.o
diff --git a/arch/mips/lib-32/csum_partial.S b/arch/mips/lib-32/csum_partial.S
deleted file mode 100644
index ea257dbdcc40..000000000000
--- a/arch/mips/lib-32/csum_partial.S
+++ /dev/null
@@ -1,240 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 1998 Ralf Baechle
- */
-#include <asm/asm.h>
-#include <asm/regdef.h>
-
-#define ADDC(sum,reg) \
- addu sum, reg; \
- sltu v1, sum, reg; \
- addu sum, v1
-
-#define CSUM_BIGCHUNK(src, offset, sum, t0, t1, t2, t3) \
- lw t0, (offset + 0x00)(src); \
- lw t1, (offset + 0x04)(src); \
- lw t2, (offset + 0x08)(src); \
- lw t3, (offset + 0x0c)(src); \
- ADDC(sum, t0); \
- ADDC(sum, t1); \
- ADDC(sum, t2); \
- ADDC(sum, t3); \
- lw t0, (offset + 0x10)(src); \
- lw t1, (offset + 0x14)(src); \
- lw t2, (offset + 0x18)(src); \
- lw t3, (offset + 0x1c)(src); \
- ADDC(sum, t0); \
- ADDC(sum, t1); \
- ADDC(sum, t2); \
- ADDC(sum, t3); \
-
-/*
- * a0: source address
- * a1: length of the area to checksum
- * a2: partial checksum
- */
-
-#define src a0
-#define dest a1
-#define sum v0
-
- .text
- .set noreorder
-
-/* unknown src alignment and < 8 bytes to go */
-small_csumcpy:
- move a1, t2
-
- andi t0, a1, 4
- beqz t0, 1f
- andi t0, a1, 2
-
- /* Still a full word to go */
- ulw t1, (src)
- addiu src, 4
- ADDC(sum, t1)
-
-1: move t1, zero
- beqz t0, 1f
- andi t0, a1, 1
-
- /* Still a halfword to go */
- ulhu t1, (src)
- addiu src, 2
-
-1: beqz t0, 1f
- sll t1, t1, 16
-
- lbu t2, (src)
- nop
-
-#ifdef __MIPSEB__
- sll t2, t2, 8
-#endif
- or t1, t2
-
-1: ADDC(sum, t1)
-
- /* fold checksum */
- sll v1, sum, 16
- addu sum, v1
- sltu v1, sum, v1
- srl sum, sum, 16
- addu sum, v1
-
- /* odd buffer alignment? */
- beqz t7, 1f
- nop
- sll v1, sum, 8
- srl sum, sum, 8
- or sum, v1
- andi sum, 0xffff
-1:
- .set reorder
- /* Add the passed partial csum. */
- ADDC(sum, a2)
- jr ra
- .set noreorder
-
-/* ------------------------------------------------------------------------- */
-
- .align 5
-LEAF(csum_partial)
- move sum, zero
- move t7, zero
-
- sltiu t8, a1, 0x8
- bnez t8, small_csumcpy /* < 8 bytes to copy */
- move t2, a1
-
- beqz a1, out
- andi t7, src, 0x1 /* odd buffer? */
-
-hword_align:
- beqz t7, word_align
- andi t8, src, 0x2
-
- lbu t0, (src)
- subu a1, a1, 0x1
-#ifdef __MIPSEL__
- sll t0, t0, 8
-#endif
- ADDC(sum, t0)
- addu src, src, 0x1
- andi t8, src, 0x2
-
-word_align:
- beqz t8, dword_align
- sltiu t8, a1, 56
-
- lhu t0, (src)
- subu a1, a1, 0x2
- ADDC(sum, t0)
- sltiu t8, a1, 56
- addu src, src, 0x2
-
-dword_align:
- bnez t8, do_end_words
- move t8, a1
-
- andi t8, src, 0x4
- beqz t8, qword_align
- andi t8, src, 0x8
-
- lw t0, 0x00(src)
- subu a1, a1, 0x4
- ADDC(sum, t0)
- addu src, src, 0x4
- andi t8, src, 0x8
-
-qword_align:
- beqz t8, oword_align
- andi t8, src, 0x10
-
- lw t0, 0x00(src)
- lw t1, 0x04(src)
- subu a1, a1, 0x8
- ADDC(sum, t0)
- ADDC(sum, t1)
- addu src, src, 0x8
- andi t8, src, 0x10
-
-oword_align:
- beqz t8, begin_movement
- srl t8, a1, 0x7
-
- lw t3, 0x08(src)
- lw t4, 0x0c(src)
- lw t0, 0x00(src)
- lw t1, 0x04(src)
- ADDC(sum, t3)
- ADDC(sum, t4)
- ADDC(sum, t0)
- ADDC(sum, t1)
- subu a1, a1, 0x10
- addu src, src, 0x10
- srl t8, a1, 0x7
-
-begin_movement:
- beqz t8, 1f
- andi t2, a1, 0x40
-
-move_128bytes:
- CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4)
- CSUM_BIGCHUNK(src, 0x20, sum, t0, t1, t3, t4)
- CSUM_BIGCHUNK(src, 0x40, sum, t0, t1, t3, t4)
- CSUM_BIGCHUNK(src, 0x60, sum, t0, t1, t3, t4)
- subu t8, t8, 0x01
- bnez t8, move_128bytes
- addu src, src, 0x80
-
-1:
- beqz t2, 1f
- andi t2, a1, 0x20
-
-move_64bytes:
- CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4)
- CSUM_BIGCHUNK(src, 0x20, sum, t0, t1, t3, t4)
- addu src, src, 0x40
-
-1:
- beqz t2, do_end_words
- andi t8, a1, 0x1c
-
-move_32bytes:
- CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4)
- andi t8, a1, 0x1c
- addu src, src, 0x20
-
-do_end_words:
- beqz t8, maybe_end_cruft
- srl t8, t8, 0x2
-
-end_words:
- lw t0, (src)
- subu t8, t8, 0x1
- ADDC(sum, t0)
- bnez t8, end_words
- addu src, src, 0x4
-
-maybe_end_cruft:
- andi t2, a1, 0x3
-
-small_memcpy:
- j small_csumcpy; move a1, t2
- beqz t2, out
- move a1, t2
-
-end_bytes:
- lb t0, (src)
- subu a1, a1, 0x1
- bnez a2, end_bytes
- addu src, src, 0x1
-
-out:
- jr ra
- move v0, sum
- END(csum_partial)
diff --git a/arch/mips/lib-64/Makefile b/arch/mips/lib-64/Makefile
index ad285786e74b..dcd4d2ed2ac4 100644
--- a/arch/mips/lib-64/Makefile
+++ b/arch/mips/lib-64/Makefile
@@ -2,7 +2,7 @@
# Makefile for MIPS-specific library files..
#
-lib-y += csum_partial.o memset.o watch.o
+lib-y += memset.o watch.o
obj-$(CONFIG_CPU_MIPS32) += dump_tlb.o
obj-$(CONFIG_CPU_MIPS64) += dump_tlb.o
diff --git a/arch/mips/lib-64/csum_partial.S b/arch/mips/lib-64/csum_partial.S
deleted file mode 100644
index 25aba660cc9c..000000000000
--- a/arch/mips/lib-64/csum_partial.S
+++ /dev/null
@@ -1,242 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Quick'n'dirty IP checksum ...
- *
- * Copyright (C) 1998, 1999 Ralf Baechle
- * Copyright (C) 1999 Silicon Graphics, Inc.
- */
-#include <asm/asm.h>
-#include <asm/regdef.h>
-
-#define ADDC(sum,reg) \
- addu sum, reg; \
- sltu v1, sum, reg; \
- addu sum, v1
-
-#define CSUM_BIGCHUNK(src, offset, sum, t0, t1, t2, t3) \
- lw t0, (offset + 0x00)(src); \
- lw t1, (offset + 0x04)(src); \
- lw t2, (offset + 0x08)(src); \
- lw t3, (offset + 0x0c)(src); \
- ADDC(sum, t0); \
- ADDC(sum, t1); \
- ADDC(sum, t2); \
- ADDC(sum, t3); \
- lw t0, (offset + 0x10)(src); \
- lw t1, (offset + 0x14)(src); \
- lw t2, (offset + 0x18)(src); \
- lw t3, (offset + 0x1c)(src); \
- ADDC(sum, t0); \
- ADDC(sum, t1); \
- ADDC(sum, t2); \
- ADDC(sum, t3); \
-
-/*
- * a0: source address
- * a1: length of the area to checksum
- * a2: partial checksum
- */
-
-#define src a0
-#define sum v0
-
- .text
- .set noreorder
-
-/* unknown src alignment and < 8 bytes to go */
-small_csumcpy:
- move a1, ta2
-
- andi ta0, a1, 4
- beqz ta0, 1f
- andi ta0, a1, 2
-
- /* Still a full word to go */
- ulw ta1, (src)
- daddiu src, 4
- ADDC(sum, ta1)
-
-1: move ta1, zero
- beqz ta0, 1f
- andi ta0, a1, 1
-
- /* Still a halfword to go */
- ulhu ta1, (src)
- daddiu src, 2
-
-1: beqz ta0, 1f
- sll ta1, ta1, 16
-
- lbu ta2, (src)
- nop
-
-#ifdef __MIPSEB__
- sll ta2, ta2, 8
-#endif
- or ta1, ta2
-
-1: ADDC(sum, ta1)
-
- /* fold checksum */
- sll v1, sum, 16
- addu sum, v1
- sltu v1, sum, v1
- srl sum, sum, 16
- addu sum, v1
-
- /* odd buffer alignment? */
- beqz t3, 1f
- nop
- sll v1, sum, 8
- srl sum, sum, 8
- or sum, v1
- andi sum, 0xffff
-1:
- .set reorder
- /* Add the passed partial csum. */
- ADDC(sum, a2)
- jr ra
- .set noreorder
-
-/* ------------------------------------------------------------------------- */
-
- .align 5
-LEAF(csum_partial)
- move sum, zero
- move t3, zero
-
- sltiu t8, a1, 0x8
- bnez t8, small_csumcpy /* < 8 bytes to copy */
- move ta2, a1
-
- beqz a1, out
- andi t3, src, 0x1 /* odd buffer? */
-
-hword_align:
- beqz t3, word_align
- andi t8, src, 0x2
-
- lbu ta0, (src)
- dsubu a1, a1, 0x1
-#ifdef __MIPSEL__
- sll ta0, ta0, 8
-#endif
- ADDC(sum, ta0)
- daddu src, src, 0x1
- andi t8, src, 0x2
-
-word_align:
- beqz t8, dword_align
- sltiu t8, a1, 56
-
- lhu ta0, (src)
- dsubu a1, a1, 0x2
- ADDC(sum, ta0)
- sltiu t8, a1, 56
- daddu src, src, 0x2
-
-dword_align:
- bnez t8, do_end_words
- move t8, a1
-
- andi t8, src, 0x4
- beqz t8, qword_align
- andi t8, src, 0x8
-
- lw ta0, 0x00(src)
- dsubu a1, a1, 0x4
- ADDC(sum, ta0)
- daddu src, src, 0x4
- andi t8, src, 0x8
-
-qword_align:
- beqz t8, oword_align
- andi t8, src, 0x10
-
- lw ta0, 0x00(src)
- lw ta1, 0x04(src)
- dsubu a1, a1, 0x8
- ADDC(sum, ta0)
- ADDC(sum, ta1)
- daddu src, src, 0x8
- andi t8, src, 0x10
-
-oword_align:
- beqz t8, begin_movement
- dsrl t8, a1, 0x7
-
- lw ta3, 0x08(src)
- lw t0, 0x0c(src)
- lw ta0, 0x00(src)
- lw ta1, 0x04(src)
- ADDC(sum, ta3)
- ADDC(sum, t0)
- ADDC(sum, ta0)
- ADDC(sum, ta1)
- dsubu a1, a1, 0x10
- daddu src, src, 0x10
- dsrl t8, a1, 0x7
-
-begin_movement:
- beqz t8, 1f
- andi ta2, a1, 0x40
-
-move_128bytes:
- CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0)
- CSUM_BIGCHUNK(src, 0x20, sum, ta0, ta1, ta3, t0)
- CSUM_BIGCHUNK(src, 0x40, sum, ta0, ta1, ta3, t0)
- CSUM_BIGCHUNK(src, 0x60, sum, ta0, ta1, ta3, t0)
- dsubu t8, t8, 0x01
- bnez t8, move_128bytes
- daddu src, src, 0x80
-
-1:
- beqz ta2, 1f
- andi ta2, a1, 0x20
-
-move_64bytes:
- CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0)
- CSUM_BIGCHUNK(src, 0x20, sum, ta0, ta1, ta3, t0)
- daddu src, src, 0x40
-
-1:
- beqz ta2, do_end_words
- andi t8, a1, 0x1c
-
-move_32bytes:
- CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0)
- andi t8, a1, 0x1c
- daddu src, src, 0x20
-
-do_end_words:
- beqz t8, maybe_end_cruft
- dsrl t8, t8, 0x2
-
-end_words:
- lw ta0, (src)
- dsubu t8, t8, 0x1
- ADDC(sum, ta0)
- bnez t8, end_words
- daddu src, src, 0x4
-
-maybe_end_cruft:
- andi ta2, a1, 0x3
-
-small_memcpy:
- j small_csumcpy; move a1, ta2 /* XXX ??? */
- beqz t2, out
- move a1, ta2
-
-end_bytes:
- lb ta0, (src)
- dsubu a1, a1, 0x1
- bnez a2, end_bytes
- daddu src, src, 0x1
-
-out:
- jr ra
- move v0, sum
- END(csum_partial)
diff --git a/arch/mips/lib/Makefile b/arch/mips/lib/Makefile
index b225543f5302..888b61ea12fe 100644
--- a/arch/mips/lib/Makefile
+++ b/arch/mips/lib/Makefile
@@ -2,8 +2,8 @@
# Makefile for MIPS-specific library files..
#
-lib-y += csum_partial_copy.o memcpy.o promlib.o strlen_user.o strncpy_user.o \
- strnlen_user.o uncached.o
+lib-y += csum_partial.o csum_partial_copy.o memcpy.o promlib.o \
+ strlen_user.o strncpy_user.o strnlen_user.o uncached.o
obj-y += iomap.o
diff --git a/arch/mips/lib/csum_partial.S b/arch/mips/lib/csum_partial.S
new file mode 100644
index 000000000000..15611d9df7ac
--- /dev/null
+++ b/arch/mips/lib/csum_partial.S
@@ -0,0 +1,258 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Quick'n'dirty IP checksum ...
+ *
+ * Copyright (C) 1998, 1999 Ralf Baechle
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ */
+#include <asm/asm.h>
+#include <asm/regdef.h>
+
+#ifdef CONFIG_64BIT
+#define T0 ta0
+#define T1 ta1
+#define T2 ta2
+#define T3 ta3
+#define T4 t0
+#define T7 t3
+#else
+#define T0 t0
+#define T1 t1
+#define T2 t2
+#define T3 t3
+#define T4 t4
+#define T7 t7
+#endif
+
+#define ADDC(sum,reg) \
+ addu sum, reg; \
+ sltu v1, sum, reg; \
+ addu sum, v1
+
+#define CSUM_BIGCHUNK(src, offset, sum, _t0, _t1, _t2, _t3) \
+ lw _t0, (offset + 0x00)(src); \
+ lw _t1, (offset + 0x04)(src); \
+ lw _t2, (offset + 0x08)(src); \
+ lw _t3, (offset + 0x0c)(src); \
+ ADDC(sum, _t0); \
+ ADDC(sum, _t1); \
+ ADDC(sum, _t2); \
+ ADDC(sum, _t3); \
+ lw _t0, (offset + 0x10)(src); \
+ lw _t1, (offset + 0x14)(src); \
+ lw _t2, (offset + 0x18)(src); \
+ lw _t3, (offset + 0x1c)(src); \
+ ADDC(sum, _t0); \
+ ADDC(sum, _t1); \
+ ADDC(sum, _t2); \
+ ADDC(sum, _t3); \
+
+/*
+ * a0: source address
+ * a1: length of the area to checksum
+ * a2: partial checksum
+ */
+
+#define src a0
+#define sum v0
+
+ .text
+ .set noreorder
+
+/* unknown src alignment and < 8 bytes to go */
+small_csumcpy:
+ move a1, T2
+
+ andi T0, a1, 4
+ beqz T0, 1f
+ andi T0, a1, 2
+
+ /* Still a full word to go */
+ ulw T1, (src)
+ PTR_ADDIU src, 4
+ ADDC(sum, T1)
+
+1: move T1, zero
+ beqz T0, 1f
+ andi T0, a1, 1
+
+ /* Still a halfword to go */
+ ulhu T1, (src)
+ PTR_ADDIU src, 2
+
+1: beqz T0, 1f
+ sll T1, T1, 16
+
+ lbu T2, (src)
+ nop
+
+#ifdef __MIPSEB__
+ sll T2, T2, 8
+#endif
+ or T1, T2
+
+1: ADDC(sum, T1)
+
+ /* fold checksum */
+ sll v1, sum, 16
+ addu sum, v1
+ sltu v1, sum, v1
+ srl sum, sum, 16
+ addu sum, v1
+
+ /* odd buffer alignment? */
+ beqz T7, 1f
+ nop
+ sll v1, sum, 8
+ srl sum, sum, 8
+ or sum, v1
+ andi sum, 0xffff
+1:
+ .set reorder
+ /* Add the passed partial csum. */
+ ADDC(sum, a2)
+ jr ra
+ .set noreorder
+
+/* ------------------------------------------------------------------------- */
+
+ .align 5
+LEAF(csum_partial)
+ move sum, zero
+ move T7, zero
+
+ sltiu t8, a1, 0x8
+ bnez t8, small_csumcpy /* < 8 bytes to copy */
+ move T2, a1
+
+ beqz a1, out
+ andi T7, src, 0x1 /* odd buffer? */
+
+hword_align:
+ beqz T7, word_align
+ andi t8, src, 0x2
+
+ lbu T0, (src)
+ LONG_SUBU a1, a1, 0x1
+#ifdef __MIPSEL__
+ sll T0, T0, 8
+#endif
+ ADDC(sum, T0)
+ PTR_ADDU src, src, 0x1
+ andi t8, src, 0x2
+
+word_align:
+ beqz t8, dword_align
+ sltiu t8, a1, 56
+
+ lhu T0, (src)
+ LONG_SUBU a1, a1, 0x2
+ ADDC(sum, T0)
+ sltiu t8, a1, 56
+ PTR_ADDU src, src, 0x2
+
+dword_align:
+ bnez t8, do_end_words
+ move t8, a1
+
+ andi t8, src, 0x4
+ beqz t8, qword_align
+ andi t8, src, 0x8
+
+ lw T0, 0x00(src)
+ LONG_SUBU a1, a1, 0x4
+ ADDC(sum, T0)
+ PTR_ADDU src, src, 0x4
+ andi t8, src, 0x8
+
+qword_align:
+ beqz t8, oword_align
+ andi t8, src, 0x10
+
+ lw T0, 0x00(src)
+ lw T1, 0x04(src)
+ LONG_SUBU a1, a1, 0x8
+ ADDC(sum, T0)
+ ADDC(sum, T1)
+ PTR_ADDU src, src, 0x8
+ andi t8, src, 0x10
+
+oword_align:
+ beqz t8, begin_movement
+ LONG_SRL t8, a1, 0x7
+
+ lw T3, 0x08(src)
+ lw T4, 0x0c(src)
+ lw T0, 0x00(src)
+ lw T1, 0x04(src)
+ ADDC(sum, T3)
+ ADDC(sum, T4)
+ ADDC(sum, T0)
+ ADDC(sum, T1)
+ LONG_SUBU a1, a1, 0x10
+ PTR_ADDU src, src, 0x10
+ LONG_SRL t8, a1, 0x7
+
+begin_movement:
+ beqz t8, 1f
+ andi T2, a1, 0x40
+
+move_128bytes:
+ CSUM_BIGCHUNK(src, 0x00, sum, T0, T1, T3, T4)
+ CSUM_BIGCHUNK(src, 0x20, sum, T0, T1, T3, T4)
+ CSUM_BIGCHUNK(src, 0x40, sum, T0, T1, T3, T4)
+ CSUM_BIGCHUNK(src, 0x60, sum, T0, T1, T3, T4)
+ LONG_SUBU t8, t8, 0x01
+ bnez t8, move_128bytes
+ PTR_ADDU src, src, 0x80
+
+1:
+ beqz T2, 1f
+ andi T2, a1, 0x20
+
+move_64bytes:
+ CSUM_BIGCHUNK(src, 0x00, sum, T0, T1, T3, T4)
+ CSUM_BIGCHUNK(src, 0x20, sum, T0, T1, T3, T4)
+ PTR_ADDU src, src, 0x40
+
+1:
+ beqz T2, do_end_words
+ andi t8, a1, 0x1c
+
+move_32bytes:
+ CSUM_BIGCHUNK(src, 0x00, sum, T0, T1, T3, T4)
+ andi t8, a1, 0x1c
+ PTR_ADDU src, src, 0x20
+
+do_end_words:
+ beqz t8, maybe_end_cruft
+ LONG_SRL t8, t8, 0x2
+
+end_words:
+ lw T0, (src)
+ LONG_SUBU t8, t8, 0x1
+ ADDC(sum, T0)
+ bnez t8, end_words
+ PTR_ADDU src, src, 0x4
+
+maybe_end_cruft:
+ andi T2, a1, 0x3
+
+small_memcpy:
+ j small_csumcpy; move a1, T2 /* XXX ??? */
+ beqz t2, out
+ move a1, T2
+
+end_bytes:
+ lb T0, (src)
+ LONG_SUBU a1, a1, 0x1
+ bnez a2, end_bytes
+ PTR_ADDU src, src, 0x1
+
+out:
+ jr ra
+ move v0, sum
+ END(csum_partial)