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Rev	Author	Line No.	Line
2	-	1	`#define BDNZ BC 16,0,`
		2	`#define BDNE BC 0,2,`
		3
		4	`/*`
		5	`* mpvecadd(mpdigit a, int alen, mpdigit b, int blen, mpdigit *sum)`
		6	`*`
		7	`* sum[0:alen] = a[0:alen-1] + b[0:blen-1]`
		8	`*`
		9	`* prereq: alen >= blen, sum has room for alen+1 digits`
		10	`*`
		11	`* R1 == a (first arg passed in R1)`
		12	`* R3 == carry`
		13	`* R4 == alen`
		14	`* R5 == b`
		15	`* R6 == blen`
		16	`* R7 == sum`
		17	`* R2 == temporary`
		18	`* R8 == temporary`
		19	`* R9 == temporary`
		20	`*/`
		21	`TEXT mpvecadd(SB),$-4`
		22
		23	`MOVW alen+4(FP), R4`
		24	`MOVW b+8(FP), R5`
		25	`MOVW blen+12(FP), R6`
		26	`MOVW sum+16(FP), R7`
		27	`SUBU R6, R4 /* calculate counter for second loop (alen > blen) */`
		28	`MOVW R0, R3`
		29
		30	`/* if blen == 0, don't need to add it in */`
		31	`BEQ R6,_add1`
		32
		33	`/* sum[0:blen-1],carry = a[0:blen-1] + b[0:blen-1] */`
		34	`_addloop1:`
		35	`MOVW 0(R1), R8`
		36	`ADDU $4, R1`
		37	`MOVW 0(R5), R9`
		38	`ADDU $4, R5`
		39	`ADDU R3, R8`
		40	`SGTU R3, R8, R3`
		41	`ADDU R8, R9`
		42	`SGTU R8, R9, R2`
		43	`ADDU R2, R3`
		44	`MOVW R9, 0(R7)`
		45	`ADDU $4, R7`
		46	`SUBU $1, R6`
		47	`BNE R6, _addloop1`
		48
		49	`_add1:`
		50	`/* if alen == blen, we're done */`
		51	`BEQ R4, _addend`
		52
		53	`/* sum[blen:alen-1],carry = a[blen:alen-1] + 0 + carry */`
		54	`_addloop2:`
		55	`MOVW 0(R1), R8`
		56	`ADDU $4, R1`
		57	`ADDU R3, R8`
		58	`SGTU R3, R8, R3`
		59	`MOVW R8, 0(R7)`
		60	`ADDU $4, R7`
		61	`SUBU $1, R4`
		62	`BNE R4, _addloop2`
		63
		64	`/* sum[alen] = carry */`
		65	`_addend:`
		66	`MOVW R3, 0(R7)`
		67	`RET`

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