1 files changed, 113 insertions, 0 deletions
diff --git a/arch/alpha/lib/clear_user.S b/arch/alpha/lib/clear_user.S
new file mode 100644
index 000000000000..8860316c1957
--- /dev/null
+++ b/arch/alpha/lib/clear_user.S
@@ -0,0 +1,113 @@
+/*
+ * arch/alpha/lib/clear_user.S
+ * Contributed by Richard Henderson <rth@tamu.edu>
+ *
+ * Zero user space, handling exceptions as we go.
+ *
+ * We have to make sure that $0 is always up-to-date and contains the
+ * right "bytes left to zero" value (and that it is updated only _after_
+ * a successful copy).  There is also some rather minor exception setup
+ * stuff.
+ *
+ * NOTE! This is not directly C-callable, because the calling semantics
+ * are different:
+ *
+ * Inputs:
+ *      length in $0
+ *      destination address in $6
+ *      exception pointer in $7
+ *      return address in $28 (exceptions expect it there)
+ *
+ * Outputs:
+ *      bytes left to copy in $0
+ *
+ * Clobbers:
+ *      $1,$2,$3,$4,$5,$6
+ */
+/* Allow an exception for an insn; exit if we get one.  */
+#define EX(x,y...)                      \
+        99: x,##y;                      \
+        .section __ex_table,"a";        \
+        .long 99b - .;                  \
+        lda $31, $exception-99b($31);   \
+        .previous
+        .set noat
+        .set noreorder
+        .align 4
+        .globl __do_clear_user
+        .ent __do_clear_user
+        .frame  $30, 0, $28
+        .prologue 0
+$loop:
+        and     $1, 3, $4       # e0    :
+        beq     $4, 1f          # .. e1 :
+0:      EX( stq_u $31, 0($6) )  # e0    : zero one word
+        subq    $0, 8, $0       # .. e1 :
+        subq    $4, 1, $4       # e0    :
+        addq    $6, 8, $6       # .. e1 :
+        bne     $4, 0b          # e1    :
+        unop                    #       :
+1:      bic     $1, 3, $1       # e0    :
+        beq     $1, $tail       # .. e1 :
+2:      EX( stq_u $31, 0($6) )  # e0    : zero four words
+        subq    $0, 8, $0       # .. e1 :
+        EX( stq_u $31, 8($6) )  # e0    :
+        subq    $0, 8, $0       # .. e1 :
+        EX( stq_u $31, 16($6) ) # e0    :
+        subq    $0, 8, $0       # .. e1 :
+        EX( stq_u $31, 24($6) ) # e0    :
+        subq    $0, 8, $0       # .. e1 :
+        subq    $1, 4, $1       # e0    :
+        addq    $6, 32, $6      # .. e1 :
+        bne     $1, 2b          # e1    :
+$tail:
+        bne     $2, 1f          # e1    : is there a tail to do?
+        ret     $31, ($28), 1   # .. e1 :
+1:      EX( ldq_u $5, 0($6) )   # e0    :
+        clr     $0              # .. e1 :
+        nop                     # e1    :
+        mskqh   $5, $0, $5      # e0    :
+        EX( stq_u $5, 0($6) )   # e0    :
+        ret     $31, ($28), 1   # .. e1 :
+__do_clear_user:
+        and     $6, 7, $4       # e0    : find dest misalignment
+        beq     $0, $zerolength # .. e1 :
+        addq    $0, $4, $1      # e0    : bias counter
+        and     $1, 7, $2       # e1    : number of bytes in tail
+        srl     $1, 3, $1       # e0    :
+        beq     $4, $loop       # .. e1 :
+        EX( ldq_u $5, 0($6) )   # e0    : load dst word to mask back in
+        beq     $1, $oneword    # .. e1 : sub-word store?
+        mskql   $5, $6, $5      # e0    : take care of misaligned head
+        addq    $6, 8, $6       # .. e1 :
+        EX( stq_u $5, -8($6) )  # e0    :
+        addq    $0, $4, $0      # .. e1 : bytes left -= 8 - misalignment
+        subq    $1, 1, $1       # e0    :
+        subq    $0, 8, $0       # .. e1 :
+        br      $loop           # e1    :
+        unop                    #       :
+$oneword:
+        mskql   $5, $6, $4      # e0    :
+        mskqh   $5, $2, $5      # e0    :
+        or      $5, $4, $5      # e1    :
+        EX( stq_u $5, 0($6) )   # e0    :
+        clr     $0              # .. e1 :
+$zerolength:
+$exception:
+        ret     $31, ($28), 1   # .. e1 :
+        .end __do_clear_user

diff --git a/arch/alpha/lib/clear_user.S b/arch/alpha/lib/clear_user.S new file mode 100644 index 000000000000..8860316c1957 --- /dev/null +++ b/arch/alpha/lib/clear_user.S
@@ -0,0 +1,113 @@
	1	/*
	2	* arch/alpha/lib/clear_user.S
	3	* Contributed by Richard Henderson <rth@tamu.edu>
	4	*
	5	* Zero user space, handling exceptions as we go.
	6	*
	7	* We have to make sure that $0 is always up-to-date and contains the
	8	* right "bytes left to zero" value (and that it is updated only _after_
	9	* a successful copy). There is also some rather minor exception setup
	10	* stuff.
	11	*
	12	* NOTE! This is not directly C-callable, because the calling semantics
	13	* are different:
	14	*
	15	* Inputs:
	16	* length in $0
	17	* destination address in $6
	18	* exception pointer in $7
	19	* return address in $28 (exceptions expect it there)
	20	*
	21	* Outputs:
	22	* bytes left to copy in $0
	23	*
	24	* Clobbers:
	25	* $1,$2,$3,$4,$5,$6
	26	*/
	27
	28	/* Allow an exception for an insn; exit if we get one. */
	29	#define EX(x,y...) \
	30	99: x,##y; \
	31	.section __ex_table,"a"; \
	32	.long 99b - .; \
	33	lda $31, $exception-99b($31); \
	34	.previous
	35
	36	.set noat
	37	.set noreorder
	38	.align 4
	39
	40	.globl __do_clear_user
	41	.ent __do_clear_user
	42	.frame $30, 0, $28
	43	.prologue 0
	44
	45	$loop:
	46	and $1, 3, $4 # e0 :
	47	beq $4, 1f # .. e1 :
	48
	49	0: EX( stq_u $31, 0($6) ) # e0 : zero one word
	50	subq $0, 8, $0 # .. e1 :
	51	subq $4, 1, $4 # e0 :
	52	addq $6, 8, $6 # .. e1 :
	53	bne $4, 0b # e1 :
	54	unop # :
	55
	56	1: bic $1, 3, $1 # e0 :
	57	beq $1, $tail # .. e1 :
	58
	59	2: EX( stq_u $31, 0($6) ) # e0 : zero four words
	60	subq $0, 8, $0 # .. e1 :
	61	EX( stq_u $31, 8($6) ) # e0 :
	62	subq $0, 8, $0 # .. e1 :
	63	EX( stq_u $31, 16($6) ) # e0 :
	64	subq $0, 8, $0 # .. e1 :
	65	EX( stq_u $31, 24($6) ) # e0 :
	66	subq $0, 8, $0 # .. e1 :
	67	subq $1, 4, $1 # e0 :
	68	addq $6, 32, $6 # .. e1 :
	69	bne $1, 2b # e1 :
	70
	71	$tail:
	72	bne $2, 1f # e1 : is there a tail to do?
	73	ret $31, ($28), 1 # .. e1 :
	74
	75	1: EX( ldq_u $5, 0($6) ) # e0 :
	76	clr $0 # .. e1 :
	77	nop # e1 :
	78	mskqh $5, $0, $5 # e0 :
	79	EX( stq_u $5, 0($6) ) # e0 :
	80	ret $31, ($28), 1 # .. e1 :
	81
	82	__do_clear_user:
	83	and $6, 7, $4 # e0 : find dest misalignment
	84	beq $0, $zerolength # .. e1 :
	85	addq $0, $4, $1 # e0 : bias counter
	86	and $1, 7, $2 # e1 : number of bytes in tail
	87	srl $1, 3, $1 # e0 :
	88	beq $4, $loop # .. e1 :
	89
	90	EX( ldq_u $5, 0($6) ) # e0 : load dst word to mask back in
	91	beq $1, $oneword # .. e1 : sub-word store?
	92
	93	mskql $5, $6, $5 # e0 : take care of misaligned head
	94	addq $6, 8, $6 # .. e1 :
	95	EX( stq_u $5, -8($6) ) # e0 :
	96	addq $0, $4, $0 # .. e1 : bytes left -= 8 - misalignment
	97	subq $1, 1, $1 # e0 :
	98	subq $0, 8, $0 # .. e1 :
	99	br $loop # e1 :
	100	unop # :
	101
	102	$oneword:
	103	mskql $5, $6, $4 # e0 :
	104	mskqh $5, $2, $5 # e0 :
	105	or $5, $4, $5 # e1 :
	106	EX( stq_u $5, 0($6) ) # e0 :
	107	clr $0 # .. e1 :
	108
	109	$zerolength:
	110	$exception:
	111	ret $31, ($28), 1 # .. e1 :
	112
	113	.end __do_clear_user