patch-2.1.30 linux/arch/sparc64/lib/checksum.S

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diff -u --recursive --new-file v2.1.29/linux/arch/sparc64/lib/checksum.S linux/arch/sparc64/lib/checksum.S
@@ -0,0 +1,567 @@
+/* checksum.S: Sparc V9 optimized checksum code.
+ *
+ *  Copyright(C) 1995 Linus Torvalds
+ *  Copyright(C) 1995 Miguel de Icaza
+ *  Copyright(C) 1996 David S. Miller
+ *  Copyright(C) 1997 Jakub Jelinek
+ *
+ * derived from:
+ *	Linux/Alpha checksum c-code
+ *      Linux/ix86 inline checksum assembly
+ *      RFC1071 Computing the Internet Checksum (esp. Jacobsons m68k code)
+ *	David Mosberger-Tang for optimized reference c-code
+ *	BSD4.4 portable checksum routine
+ */
+
+#include <asm/errno.h>
+#include <asm/head.h>
+
+#define CSUM_BIGCHUNK(buf, offset, sum, t0, t1, t2, t3, t4, t5)	\
+	ldd	[buf + offset + 0x00], t0;			\
+	ldd	[buf + offset + 0x08], t2;			\
+	addccc	t0, sum, sum;					\
+	addccc	t1, sum, sum;					\
+	ldd	[buf + offset + 0x10], t4;			\
+	addccc	t2, sum, sum;					\
+	addccc	t3, sum, sum;					\
+	ldd	[buf + offset + 0x18], t0;			\
+	addccc	t4, sum, sum;					\
+	addccc	t5, sum, sum;					\
+	addccc	t0, sum, sum;					\
+	addccc	t1, sum, sum;
+
+#define CSUM_LASTCHUNK(buf, offset, sum, t0, t1, t2, t3)	\
+	ldd	[buf - offset - 0x08], t0;			\
+	ldd	[buf - offset - 0x00], t2;			\
+	addccc	t0, sum, sum;					\
+	addccc	t1, sum, sum;					\
+	addccc	t2, sum, sum;					\
+	addccc	t3, sum, sum;
+
+	/* Do end cruft out of band to get better cache patterns. */
+csum_partial_end_cruft:
+	andcc	%o1, 8, %g0			! check how much
+	be,pn	%icc, 1f			! caller asks %o1 & 0x8
+	 and	%o1, 4, %g3			! nope, check for word remaining
+	ldd	[%o0], %g2			! load two
+	addcc	%g2, %o2, %o2			! add first word to sum
+	addccc	%g3, %o2, %o2			! add second word as well
+	add	%o0, 8, %o0			! advance buf ptr
+	addc	%g0, %o2, %o2			! add in final carry
+1:	brz,pn	%g3, 1f				! nope, skip this code
+	 andcc	%o1, 3, %o1			! check for trailing bytes
+	ld	[%o0], %g2			! load it
+	addcc	%g2, %o2, %o2			! add to sum
+	add	%o0, 4, %o0			! advance buf ptr
+	addc	%g0, %o2, %o2			! add in final carry
+1:	brz,pn	%o1, 1f				! no trailing bytes, return
+	 addcc	%o1, -1, %g0			! only one byte remains?
+	bne,pn	%icc, 2f			! at least two bytes more
+	 subcc	%o1, 2, %o1			! only two bytes more?
+	ba,pt	%xcc, 4f			! only one byte remains
+	 clr	%o4				! clear fake hword value
+2:	lduh	[%o0], %o4			! get hword
+	be,pn	%icc, 6f			! jmp if only hword remains
+	 add	%o0, 2, %o0			! advance buf ptr either way
+	sll	%o4, 16, %o4			! create upper hword
+4:	ldub	[%o0], %o5			! get final byte
+	sll	%o5, 8, %o5			! put into place
+	or	%o5, %o4, %o4			! coalese with hword (if any)
+6:	addcc	%o4, %o2, %o2			! add to sum
+1:	sllx	%g4, 32, %g4			! give gfp back
+	retl					! get outta here
+	 addc	%g0, %o2, %o0			! add final carry into retval
+
+	/* Also do alignment out of band to get better cache patterns. */
+csum_partial_fix_alignment:
+
+	/* The common case is to get called with a nicely aligned
+	 * buffer of size 0x20.  Follow the code path for that case.
+	 */
+	.globl	C_LABEL(csum_partial)
+C_LABEL(csum_partial):			/* %o0=buf, %o1=len, %o2=sum */
+	andcc	%o0, 0x7, %g0				! alignment problems?
+	be,pt	%icc, csum_partial_fix_aligned		! yep, handle it
+	 andn	%o1, 0x7f, %o3				! num loop iterations
+	cmp	%o1, 6
+	bl,pn	%icc, cpte - 0x4
+	 andcc	%o0, 0x2, %g0
+	be,pn	%icc, 1f
+	 and	%o0, 0x4, %g7
+	lduh	[%o0 + 0x00], %g2
+	sub	%o1, 2, %o1
+	add	%o0, 2, %o0
+	sll	%g2, 16, %g2
+	addcc	%g2, %o2, %o2
+	srl	%o2, 16, %g3
+	addc	%g0, %g3, %g2
+	sll	%o2, 16, %o2
+	sll	%g2, 16, %g3
+	srl	%o2, 16, %o2
+	or	%g3, %o2, %o2
+1:	brz,pn	%g7, csum_partial_fix_aligned
+	 nop
+	ld	[%o0 + 0x00], %g2
+	sub	%o1, 4, %o1
+	addcc	%g2, %o2, %o2
+	add	%o0, 4, %o0
+	addc	%g0, %o2, %o2
+csum_partial_fix_aligned:
+	brz,pt	%o3, 3f					! none to do
+	 andcc	%o1, 0x70, %g1				! clears carry flag too
+5:	CSUM_BIGCHUNK(%o0, 0x00, %o2, %o4, %o5, %g2, %g3, %g4, %g5)
+	CSUM_BIGCHUNK(%o0, 0x20, %o2, %o4, %o5, %g2, %g3, %g4, %g5)
+	CSUM_BIGCHUNK(%o0, 0x40, %o2, %o4, %o5, %g2, %g3, %g4, %g5)
+	CSUM_BIGCHUNK(%o0, 0x60, %o2, %o4, %o5, %g2, %g3, %g4, %g5)
+	sub	%o3, 128, %o3				! detract from loop iters
+	addc	%g0, %o2, %o2				! sink in final carry
+	brnz,pt	%o3, 5b					! more to do
+	 add	%o0, 128, %o0				! advance buf ptr
+3:	brz,pn	%g1, cpte				! nope
+	 andcc	%o1, 0xf, %o3				! anything left at all?
+10:	rd	%pc, %g7				! get pc
+	srl	%g1, 1, %o4				! compute offset
+	sub	%g7, %g1, %g7				! adjust jmp ptr
+	sub	%g7, %o4, %g7				! final jmp ptr adjust
+	jmp	%g7 + (cpte - 8 - 10b)			! enter the table
+	 add	%o0, %g1, %o0				! advance buf ptr
+cptbl:	CSUM_LASTCHUNK(%o0, 0x68, %o2, %g2, %g3, %g4, %g5)
+	CSUM_LASTCHUNK(%o0, 0x58, %o2, %g2, %g3, %g4, %g5)
+	CSUM_LASTCHUNK(%o0, 0x48, %o2, %g2, %g3, %g4, %g5)
+	CSUM_LASTCHUNK(%o0, 0x38, %o2, %g2, %g3, %g4, %g5)
+	CSUM_LASTCHUNK(%o0, 0x28, %o2, %g2, %g3, %g4, %g5)
+	CSUM_LASTCHUNK(%o0, 0x18, %o2, %g2, %g3, %g4, %g5)
+	CSUM_LASTCHUNK(%o0, 0x08, %o2, %g2, %g3, %g4, %g5)
+	addc	%g0, %o2, %o2				! fetch final carry
+	andcc	%o1, 0xf, %g0				! anything left at all?
+cpte:	brnz,pn	%o3, csum_partial_end_cruft		! yep, handle it
+	 sethi	%uhi(KERNBASE), %g4
+	mov	%o2, %o0				! return computed csum
+	retl						! get outta here
+	 sllx	%g4, 32, %g4				! give gfp back
+
+	.globl C_LABEL(__csum_partial_copy_start), C_LABEL(__csum_partial_copy_end)
+C_LABEL(__csum_partial_copy_start):
+
+#define EX(x,y,a,b,z)                           \
+98:     x,y;                                    \
+        .section .fixup,z##alloc,z##execinstr;  \
+        .align  4;                              \
+99:     ba,pt %xcc, 30f;                        \
+         a, b, %o3;                             \
+        .section __ex_table,z##alloc;           \
+        .align  4;                              \
+        .word   98b, 99b;                       \
+        .text;                                  \
+        .align  4
+
+#define EX2(x,y,z)                          	\
+98:     x,y;                                    \
+        .section __ex_table,z##alloc;           \
+        .align  4;                              \
+        .word   98b, 30f;                       \
+        .text;                                  \
+        .align  4
+
+#define EX3(x,y,z)                          	\
+98:     x,y;                                    \
+        .section __ex_table,z##alloc;           \
+        .align  4;                              \
+        .word   98b, 96f;                       \
+        .text;                                  \
+        .align  4
+
+#define EXT(start,end,handler,z)                \
+        .section __ex_table,z##alloc;           \
+        .align  4;                              \
+        .word   start, 0, end, handler;         \
+        .text;                                  \
+        .align  4
+
+	/* This aligned version executes typically in 8.5 superscalar cycles, this
+	 * is the best I can do.  I say 8.5 because the final add will pair with
+	 * the next ldd in the main unrolled loop.  Thus the pipe is always full.
+	 * If you change these macros (including order of instructions),
+	 * please check the fixup code below as well.
+	 */
+#define CSUMCOPY_BIGCHUNK_ALIGNED(src, dst, sum, off, t0, t1, t2, t3, t4, t5, t6, t7)	\
+	ldd	[src + off + 0x00], t0;							\
+	ldd	[src + off + 0x08], t2;							\
+	addccc	t0, sum, sum;								\
+	ldd	[src + off + 0x10], t4;							\
+	addccc	t1, sum, sum;								\
+	ldd	[src + off + 0x18], t6;							\
+	addccc	t2, sum, sum;								\
+	std	t0, [dst + off + 0x00];							\
+	addccc	t3, sum, sum;								\
+	std	t2, [dst + off + 0x08];							\
+	addccc	t4, sum, sum;								\
+	std	t4, [dst + off + 0x10];							\
+	addccc	t5, sum, sum;								\
+	std	t6, [dst + off + 0x18];							\
+	addccc	t6, sum, sum;								\
+	addccc	t7, sum, sum;
+
+	/* 12 superscalar cycles seems to be the limit for this case,
+	 * because of this we thus do all the ldd's together to get
+	 * Viking MXCC into streaming mode.  Ho hum...
+	 */
+#define CSUMCOPY_BIGCHUNK(src, dst, sum, off, t0, t1, t2, t3, t4, t5, t6, t7)	\
+	ldd	[src + off + 0x00], t0;						\
+	ldd	[src + off + 0x08], t2;						\
+	ldd	[src + off + 0x10], t4;						\
+	ldd	[src + off + 0x18], t6;						\
+	st	t0, [dst + off + 0x00];						\
+	addccc	t0, sum, sum;							\
+	st	t1, [dst + off + 0x04];						\
+	addccc	t1, sum, sum;							\
+	st	t2, [dst + off + 0x08];						\
+	addccc	t2, sum, sum;							\
+	st	t3, [dst + off + 0x0c];						\
+	addccc	t3, sum, sum;							\
+	st	t4, [dst + off + 0x10];						\
+	addccc	t4, sum, sum;							\
+	st	t5, [dst + off + 0x14];						\
+	addccc	t5, sum, sum;							\
+	st	t6, [dst + off + 0x18];						\
+	addccc	t6, sum, sum;							\
+	st	t7, [dst + off + 0x1c];						\
+	addccc	t7, sum, sum;
+
+	/* Yuck, 6 superscalar cycles... */
+#define CSUMCOPY_LASTCHUNK(src, dst, sum, off, t0, t1, t2, t3)	\
+	ldd	[src - off - 0x08], t0;				\
+	ldd	[src - off - 0x00], t2;				\
+	addccc	t0, sum, sum;					\
+	st	t0, [dst - off - 0x08];				\
+	addccc	t1, sum, sum;					\
+	st	t1, [dst - off - 0x04];				\
+	addccc	t2, sum, sum;					\
+	st	t2, [dst - off - 0x00];				\
+	addccc	t3, sum, sum;					\
+	st	t3, [dst - off + 0x04];
+
+	/* Handle the end cruft code out of band for better cache patterns. */
+cc_end_cruft:
+	andcc	%o3, 8, %g0		! begin checks for that code
+	be,pn	%icc, 1f
+	 and	%o3, 4, %g5
+	EX(ldd	[%o0 + 0x00], %g2, and %o3, 0xf,#)
+	add	%o1, 8, %o1
+	addcc	%g2, %g7, %g7
+	add	%o0, 8, %o0
+	addccc	%g3, %g7, %g7
+	EX2(st	%g2, [%o1 - 0x08],#)
+	addc	%g0, %g7, %g7
+	EX2(st	%g3, [%o1 - 0x04],#)
+1:	brz,pt	%g5, 1f
+	 andcc	%o3, 3, %o3
+	EX(ld	[%o0 + 0x00], %g2, add %o3, 4,#)
+	add	%o1, 4, %o1
+	addcc	%g2, %g7, %g7
+	EX2(st	%g2, [%o1 - 0x04],#)
+	addc	%g0, %g7, %g7
+	add	%o0, 4, %o0
+1:	brz,pn	%o3, 1f
+	 addcc	%o3, -1, %g0
+	bne,pn	%icc, 2f
+	 subcc	%o3, 2, %o3
+	ba,pt	%xcc, 4f
+	 clr	%o4
+2:	EX(lduh	[%o0 + 0x00], %o4, add %o3, 2,#)
+	add	%o0, 2, %o0
+	EX2(sth	%o4, [%o1 + 0x00],#)
+	be,pn	%icc, 6f
+	 add	%o1, 2, %o1
+	sll	%o4, 16, %o4
+4:	EX(ldub	[%o0 + 0x00], %o5, add %g0, 1,#)
+	EX2(stb	%o5, [%o1 + 0x00],#)
+	sll	%o5, 8, %o5
+	or	%o5, %o4, %o4
+6:	addcc	%o4, %g7, %g7
+1:	sllx	%g4, 32, %g4
+	retl
+	 addc	%g0, %g7, %o0
+
+	/* Sun, you just can't beat me, you just can't.  Stop trying,
+	 * give up.  I'm serious, I am going to kick the living shit
+	 * out of you, game over, lights out.
+	 */
+	.align	8
+	.globl	C_LABEL(__csum_partial_copy_sparc_generic)
+C_LABEL(__csum_partial_copy_sparc_generic):
+					/* %o0=src, %o1=dest, %g1=len, %g7=sum */
+	xor	%o0, %o1, %o4		! get changing bits
+	andcc	%o4, 3, %g0		! check for mismatched alignment
+	bne,pn	%icc, ccslow		! better this than unaligned/fixups
+	 andcc	%o0, 7, %g0		! need to align things?
+	be,pt	%icc, cc_dword_aligned	! yes, we check for short lengths there
+	 andn	%g1, 0x7f, %g2		! can we use unrolled loop?
+	cmp	%g1, 6
+	bl,a,pn	%icc, ccte
+	 andcc	%g1, 0xf, %o3
+	andcc	%o0, 0x1, %g0
+	bne,pn	%icc, ccslow
+	 andcc	%o0, 0x2, %g0
+	be,pn	%icc, 1f
+	 andcc	%o0, 0x4, %g0
+	EX(lduh	[%o0 + 0x00], %g4, add %g1, 0,#)
+	sub	%g1, 2, %g1
+	EX2(sth	%g4, [%o1 + 0x00],#)
+	add	%o0, 2, %o0
+	sll	%g4, 16, %g4
+	addcc	%g4, %g7, %g7
+	add	%o1, 2, %o1
+	srl	%g7, 16, %g3
+	addc	%g0, %g3, %g4
+	sll	%g7, 16, %g7
+	sll	%g4, 16, %g3
+	srl	%g7, 16, %g7
+	andcc	%o0, 0x4, %g0
+	or	%g3, %g7, %g7
+1:	be,pt	%icc, 3f
+	 andn	%g1, 0x7f, %g0
+	EX(ld	[%o0 + 0x00], %g4, add %g1, 0,#)
+	sub	%g1, 4, %g1
+	EX2(st	%g4, [%o1 + 0x00],#)
+	add	%o0, 4, %o0
+	addcc	%g4, %g7, %g7
+	add	%o1, 4, %o1
+	addc	%g0, %g7, %g7
+cc_dword_aligned:
+3:	brz,pn	%g2, 3f			! nope, less than one loop remains
+	 andcc	%o1, 4, %g0		! dest aligned on 4 or 8 byte boundry?
+	be,pn	%icc, ccdbl + 4		! 8 byte aligned, kick ass
+5:	CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x00,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
+	CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x20,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
+	CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x40,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
+	CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x60,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
+10:	EXT(5b, 10b, 20f,#)		! note for exception handling
+	sub	%g1, 128, %g1		! detract from length
+	addc	%g0, %g7, %g7		! add in last carry bit
+	andncc	%g1, 0x7f, %g0		! more to csum?
+	add	%o0, 128, %o0		! advance src ptr
+	bne,pt	%icc, 5b		! we did not go negative, continue looping
+	 add	%o1, 128, %o1		! advance dest ptr
+3:	andcc	%g1, 0x70, %o2		! can use table?
+ccmerge:be,pn	%icc, ccte		! nope, go and check for end cruft
+	 andcc	%g1, 0xf, %o3		! get low bits of length (clears carry btw)
+	srl	%o2, 1, %o4		! begin negative offset computation
+13:	rd	%pc, %o5		! set up table ptr end
+	add	%o0, %o2, %o0		! advance src ptr
+	sub	%o5, %o4, %o5		! continue table calculation
+	sll	%o2, 1, %g2		! constant multiplies are fun...
+	sub	%o5, %g2, %o5		! some more adjustments
+	jmpl	%o5 + (12f-13b), %g0	! jump into it, duff style, wheee...
+	 add	%o1, %o2, %o1		! advance dest ptr (carry is clear btw)
+cctbl:	CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x68,%g2,%g3,%g4,%g5)
+	CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x58,%g2,%g3,%g4,%g5)
+	CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x48,%g2,%g3,%g4,%g5)
+	CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x38,%g2,%g3,%g4,%g5)
+	CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x28,%g2,%g3,%g4,%g5)
+	CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x18,%g2,%g3,%g4,%g5)
+	CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x08,%g2,%g3,%g4,%g5)
+12:	EXT(cctbl, 12b, 22f,#)		! note for exception table handling
+	addc	%g0, %g7, %g7
+	andcc	%o3, 0xf, %g0		! check for low bits set
+ccte:	bne,pn	%icc, cc_end_cruft	! something left, handle it out of band
+	 sethi	%uhi(KERNBASE), %g4	! restore gfp
+	mov	%g7, %o0		! give em the computed checksum
+	retl				! return
+	 sllx	%g4, 32, %g4		! finish gfp restoration
+ccdbl:	CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x00,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
+	CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x20,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
+	CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x40,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
+	CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x60,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
+11:	EXT(ccdbl, 11b, 21f,#)		! note for exception table handling
+	sub	%g1, 128, %g1		! detract from length
+	addc	%g0, %g7, %g7		! add in last carry bit
+	andncc	%g1, 0x7f, %g0		! more to csum?
+	add	%o0, 128, %o0		! advance src ptr
+	bne,pt	%icc, ccdbl		! we did not go negative, continue looping
+	 add	%o1, 128, %o1		! advance dest ptr
+	ba,pt	%xcc, ccmerge		! finish it off, above
+	 andcc	%g1, 0x70, %o2		! can use table? (clears carry btw)
+
+ccslow:	mov	0, %g5
+	brlez,pn %g1, 4f
+	 andcc	%o0, 1, %o5		
+	be,a,pt	%icc, 1f
+	 srl	%g1, 1, %o3		
+	sub	%g1, 1, %g1	
+	EX(ldub	[%o0], %g5, add %g1, 1,#)
+	add	%o0, 1, %o0	
+	EX2(stb	%g5, [%o1],#)
+	srl	%g1, 1, %o3
+	add	%o1, 1, %o1
+1:	brz,a,pn %o3, 3f
+	 andcc	%g1, 1, %g0
+	andcc	%o0, 2, %g0	
+	be,a,pt	%icc, 1f
+	 srl	%o3, 1, %o3
+	EX(lduh	[%o0], %o4, add %g1, 0,#)
+	sub	%g1, 2, %g1	
+	srl	%o4, 8, %g2
+	sub	%o3, 1, %o3	
+	EX2(stb	%g2, [%o1],#)
+	add	%o4, %g5, %g5
+	EX2(stb	%o4, [%o1 + 1],#)
+	add	%o0, 2, %o0	
+	srl	%o3, 1, %o3
+	add	%o1, 2, %o1
+1:	brz,a,pn %o3, 2f		
+	 andcc	%g1, 2, %g0
+	EX3(ld	[%o0], %o4,#)
+5:	srl	%o4, 24, %g2
+	srl	%o4, 16, %g3
+	EX2(stb	%g2, [%o1],#)
+	srl	%o4, 8, %g2
+	EX2(stb	%g3, [%o1 + 1],#)
+	add	%o0, 4, %o0
+	EX2(stb	%g2, [%o1 + 2],#)
+	addcc	%o4, %g5, %g5
+	EX2(stb	%o4, [%o1 + 3],#)
+	addc	%g5, %g0, %g5	! I am now to lazy to optimize this (question is if it
+	add	%o1, 4, %o1	! is worthy). Maybe some day - with the sll/srl
+	subcc	%o3, 1, %o3	! tricks
+	bne,a,pt %icc, 5b
+	 EX3(ld	[%o0], %o4,#)
+	sll	%g5, 16, %g2
+	srl	%g5, 16, %g5
+	srl	%g2, 16, %g2
+	andcc	%g1, 2, %g0
+	add	%g2, %g5, %g5 
+2:	be,a,pt	%icc, 3f		
+	 andcc	%g1, 1, %g0
+	EX(lduh	[%o0], %o4, and %g1, 3,#)
+	andcc	%g1, 1, %g0
+	srl	%o4, 8, %g2
+	add	%o0, 2, %o0	
+	EX2(stb	%g2, [%o1],#)
+	add	%g5, %o4, %g5
+	EX2(stb	%o4, [%o1 + 1],#)
+	add	%o1, 2, %o1
+3:	be,a,pt	%icc, 1f		
+	 sll	%g5, 16, %o4
+	EX(ldub	[%o0], %g2, add %g0, 1,#)
+	sll	%g2, 8, %o4	
+	EX2(stb	%g2, [%o1],#)
+	add	%g5, %o4, %g5
+	sll	%g5, 16, %o4
+1:	addcc	%o4, %g5, %g5
+	srl	%g5, 16, %o4
+	addc	%g0, %o4, %g5
+	brz,pt	%o5, 4f
+	 srl	%g5, 8, %o4
+	and	%g5, 0xff, %g2
+	and	%o4, 0xff, %o4
+	sll	%g2, 8, %g2
+	or	%g2, %o4, %g5
+4:	addcc	%g7, %g5, %g7
+	retl	
+	 addc	%g0, %g7, %o0
+C_LABEL(__csum_partial_copy_end):
+
+        .section .fixup,#alloc,#execinstr
+        .align  4
+/* We do these strange calculations for the csum_*_from_user case only, ie.
+ * we only bother with faults on loads... */
+
+/* o2 = ((g2%20)&3)*8
+ * o3 = g1 - (g2/20)*32 - o2 */
+20:
+	cmp	%g2, 20
+	blu,a,pn %icc, 1f
+	 and	%g2, 3, %o2
+	sub	%g1, 32, %g1
+	ba,pt	%xcc, 20b
+	 sub	%g2, 20, %g2
+1:
+	sll	%o2, 3, %o2
+	ba,pt	%xcc, 31f
+	 sub	%g1, %o2, %o3
+
+/* o2 = (!(g2 & 15) ? 0 : (((g2 & 15) + 1) & ~1)*8)
+ * o3 = g1 - (g2/16)*32 - o2 */
+21:
+	andcc	%g2, 15, %o3
+	srl	%g2, 4, %g2
+	be,a,pn	%icc, 1f
+	 clr	%o2
+	add	%o3, 1, %o3
+	and	%o3, 14, %o3
+	sll	%o3, 3, %o2
+1:
+	sll	%g2, 5, %g2
+	sub	%g1, %g2, %o3
+	ba,pt	%xcc, 31f
+	 sub	%o3, %o2, %o3
+
+/* o0 += (g2/10)*16 - 0x70
+ * 01 += (g2/10)*16 - 0x70
+ * o2 = (g2 % 10) ? 8 : 0
+ * o3 += 0x70 - (g2/10)*16 - o2 */
+22:
+	cmp	%g2, 10
+	blu,a,pt %xcc, 1f
+	 sub	%o0, 0x70, %o0
+	add	%o0, 16, %o0
+	add	%o1, 16, %o1
+	sub	%o3, 16, %o3
+	ba,pt	%xcc, 22b
+	 sub	%g2, 10, %g2
+1:
+	sub	%o1, 0x70, %o1
+	add	%o3, 0x70, %o3
+	clr	%o2
+	movne	%g2, 8, %o2
+	ba,pt	%xcc, 31f
+	 sub	%o3, %o2, %o3
+96:
+	and	%g1, 3, %g1
+	sll	%o3, 2, %o3
+	add	%g1, %o3, %o3
+30:
+/* %o1 is dst
+ * %o3 is # bytes to zero out
+ * %o4 is faulting address
+ * %o5 is %pc where fault occured */
+	clr	%o2
+31:
+/* %o0 is src
+ * %o1 is dst
+ * %o2 is # of bytes to copy from src to dst
+ * %o3 is # bytes to zero out
+ * %o4 is faulting address
+ * %o5 is %pc where fault occured */
+	save	%sp, -136, %sp
+        mov     %i5, %o0
+        mov     %i7, %o1
+        mov	%i4, %o2
+        call    C_LABEL(lookup_fault)
+	 mov	%g7, %i4
+	cmp	%o0, 2
+	bne,pn	%icc, 1f
+	 add	%g0, -EFAULT, %i5
+	brz,pn	%i2, 2f
+	 mov	%i0, %o1
+	mov	%i1, %o0
+5:
+	call	C_LABEL(__memcpy)
+	 mov	%i2, %o2
+	brnz,a,pn %o0, 2f
+	 add	%i3, %i2, %i3
+	add	%i1, %i2, %i1
+2:
+	mov	%i1, %o0
+	call	C_LABEL(__bzero)
+	 mov	%i3, %o1
+1:
+	ldx	[%sp + 264], %o2		! struct_ptr of parent
+	st	%i5, [%o2]
+	ret
+	 restore
+
+        .section __ex_table,#alloc
+        .align 4
+        .word 5b,2

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TCL-scripts by Sam Shen, slshen@lbl.gov