alpha/lib/ev6-clear_user.S

18  *	E	- either cluster
53 	and	$16, 7, $4	# .. E  .. ..	: find dest head misalignment
56 	addq	$0, $4, $1	# .. .. .. E	: bias counter
57 	and	$1, 7, $2	# .. .. E  ..	: number of misaligned bytes in tail
60 	srl	$1, 3, $1	# .. E  .. ..	: number of quadwords to clear
68 	beq	$1, $onebyte	# .. .. U  ..	: sub-word store?
70 	addq	$16, 8, $16	# E  .. .. .. 	: L U U L
73 	subq	$1, 1, $1	# .. .. E  ..	:
74 	addq	$0, $4, $0	# .. E  .. ..	: bytes left -= 8 - misalignment
75 	subq	$0, 8, $0	# E  .. .. ..	: U L U L
81  * $1 is number of quadwords to clear (zero is a valid value)
86 	subq	$1, 16, $4	# .. .. .. E	: If < 16, we can not use the huge loop
87 	and	$16, 0x3f, $2	# .. .. E  ..	: Forward work for huge loop
88 	subq	$2, 0x40, $3	# .. E  .. ..	: bias counter (huge loop)
98 	nop			# .. .. .. E
99 	nop			# .. .. E  ..
100 	nop			# .. E  .. ..
105 	addq	$3, 8, $3	# .. .. E  ..
106 	subq	$0, 8, $0	# .. E  .. ..
107 	nop			# E  .. .. ..	: U L U L
109 	nop			# .. .. .. E
110 	subq	$1, 1, $1	# .. .. E  ..
111 	addq	$16, 8, $16	# .. E  .. ..
117  * $1 is the number of quads left
120  * CWG Section 3.7.6: do not expect a sustained store rate of > 1/cycle
132 	nop			# E :
133 	nop			# E :
134 	nop			# E :
135 	bis	$16,$16,$3	# E : U L U L : Initial wh64 address is dest
140 	subq	$1, 16, $4	# .. .. E  ..	: Forward calculation - repeat the loop?
142 	subq	$0, 8, $0	# E  .. .. ..	: U L U L
144 	addq	$16, 128, $3	# E : Target address of wh64
147 	subq	$0, 16, $0	# E : U L L U
149 	nop			# E :
152 	subq	$0, 168, $5	# E : U L L U : two trips through the loop left?
155 	subq	$0, 16, $0	# E :
158 	cmovlt	$5, $16, $3	# E : U L L U : Latency 2, extra mapping cycle
160 	subq	$1, 8, $1	# E :
161 	subq	$0, 16, $0	# E :
163 	nop			# E : U L U L
165 	nop			# E :
166 	subq	$0, 8, $0	# E :
167 	addq	$16, 64, $16	# E :
172 	# $1 is the number of quadwords left to go.
174 	nop			# .. .. .. E
175 	nop			# .. .. E  ..
176 	nop			# .. E  .. ..
177 	beq	$1, $trailbytes	# U  .. .. ..	: U L U L : Only 0..7 bytes to go
181 	subq	$1, 1, $1	# .. .. E  ..
182 	subq	$0, 8, $0	# .. E  .. ..
183 	nop			# E  .. .. ..	: U L U L
185 	nop			# .. .. .. E
186 	nop			# .. .. E  ..
187 	addq	$16, 8, $16	# .. E  .. ..
188 	bgt	$1, $onequad	# U  .. .. ..	: U L U L
192 	nop			# .. .. .. E
193 	nop			# .. .. E  ..
194 	nop			# .. E  .. ..
202 	subq	$0, 1, $0	# .. .. E  ..	:
203 	addq	$16, 1, $16	# .. E  .. ..	:
208 	nop			# .. .. .. E	:
209 	nop			# .. .. E  ..	:
210 	nop			# .. E  .. ..	:
211 	ret	$31, ($26), 1	# L0 .. .. ..	: L U L U