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+/*
+ * linux/arch/alpha/memset.S
+ *
+ * This is an efficient (and small) implementation of the C library "memset()"
+ * function for the alpha.
+ *
+ * (C) Copyright 1996 Linus Torvalds
+ *
+ * This routine is "moral-ware": you are free to use it any way you wish, and
+ * the only obligation I put on you is a moral one: if you make any improvements
+ * to the routine, please send me your improvements for me to use similarly.
+ *
+ * The scheduling comments are according to the EV5 documentation (and done by
+ * hand, so they might well be incorrect, please do tell me about it..)
+ */
+
+ .set noat
+ .set noreorder
+.text
+ .globl memset
+ .globl __memset
+ .globl __memsetw
+ .globl __constant_c_memset
+ .ent __memset
+.align 5
+__memset:
+ .frame $30,0,$26,0
+ .prologue 0
+
+ and $17,255,$1 /* E1 */
+ insbl $17,1,$17 /* .. E0 */
+ bis $17,$1,$17 /* E0 (p-c latency, next cycle) */
+ sll $17,16,$1 /* E1 (p-c latency, next cycle) */
+
+ bis $17,$1,$17 /* E0 (p-c latency, next cycle) */
+ sll $17,32,$1 /* E1 (p-c latency, next cycle) */
+ bis $17,$1,$17 /* E0 (p-c latency, next cycle) */
+ ldq_u $31,0($30) /* .. E1 */
+
+.align 5
+__constant_c_memset:
+ addq $18,$16,$6 /* E0 */
+ bis $16,$16,$0 /* .. E1 */
+ xor $16,$6,$1 /* E0 */
+ ble $18,end /* .. E1 */
+
+ bic $1,7,$1 /* E0 */
+ beq $1,within_one_quad /* .. E1 (note EV5 zero-latency forwarding) */
+ and $16,7,$3 /* E0 */
+ beq $3,aligned /* .. E1 (note EV5 zero-latency forwarding) */
+
+ ldq_u $4,0($16) /* E0 */
+ bis $16,$16,$5 /* .. E1 */
+ insql $17,$16,$2 /* E0 */
+ subq $3,8,$3 /* .. E1 */
+
+ addq $18,$3,$18 /* E0 $18 is new count ($3 is negative) */
+ mskql $4,$16,$4 /* .. E1 (and possible load stall) */
+ subq $16,$3,$16 /* E0 $16 is new aligned destination */
+ bis $2,$4,$1 /* .. E1 */
+
+ bis $31,$31,$31 /* E0 */
+ ldq_u $31,0($30) /* .. E1 */
+ stq_u $1,0($5) /* E0 */
+ bis $31,$31,$31 /* .. E1 */
+
+.align 4
+aligned:
+ sra $18,3,$3 /* E0 */
+ and $18,7,$18 /* .. E1 */
+ bis $16,$16,$5 /* E0 */
+ beq $3,no_quad /* .. E1 */
+
+.align 3
+loop:
+ stq $17,0($5) /* E0 */
+ subq $3,1,$3 /* .. E1 */
+ addq $5,8,$5 /* E0 */
+ bne $3,loop /* .. E1 */
+
+no_quad:
+ bis $31,$31,$31 /* E0 */
+ beq $18,end /* .. E1 */
+ ldq $7,0($5) /* E0 */
+ mskqh $7,$6,$2 /* .. E1 (and load stall) */
+
+ insqh $17,$6,$4 /* E0 */
+ bis $2,$4,$1 /* .. E1 */
+ stq $1,0($5) /* E0 */
+ ret $31,($26),1 /* .. E1 */
+
+.align 3
+within_one_quad:
+ ldq_u $1,0($16) /* E0 */
+ insql $17,$16,$2 /* E1 */
+ mskql $1,$16,$4 /* E0 (after load stall) */
+ bis $2,$4,$2 /* E0 */
+
+ mskql $2,$6,$4 /* E0 */
+ mskqh $1,$6,$2 /* .. E1 */
+ bis $2,$4,$1 /* E0 */
+ stq_u $1,0($16) /* E0 */
+
+end:
+ ret $31,($26),1 /* E1 */
+ .end __memset
+
+ .align 5
+ .ent __memsetw
+__memsetw:
+ .prologue 0
+
+ inswl $17,0,$1 /* E0 */
+ inswl $17,2,$2 /* E0 */
+ inswl $17,4,$3 /* E0 */
+ or $1,$2,$1 /* .. E1 */
+ inswl $17,6,$4 /* E0 */
+ or $1,$3,$1 /* .. E1 */
+ or $1,$4,$17 /* E0 */
+ br __constant_c_memset /* .. E1 */
+
+ .end __memsetw
+
+memset = __memset