patch-2.1.26 linux/arch/alpha/lib/stxcpy.S
Next file: linux/arch/alpha/lib/stxncpy.S
Previous file: linux/arch/alpha/lib/strncpy_from_user.S
Back to the patch index
Back to the overall index
- Lines: 185
- Date:
Thu Feb 6 14:42:35 1997
- Orig file:
v2.1.25/linux/arch/alpha/lib/stxcpy.S
- Orig date:
Sat Oct 19 10:07:28 1996
diff -u --recursive --new-file v2.1.25/linux/arch/alpha/lib/stxcpy.S linux/arch/alpha/lib/stxcpy.S
@@ -13,7 +13,7 @@
* a1 = SRC
*
* On output:
- * t8 = bitmask (with one bit set) indicating the last byte written
+ * t12 = bitmask (with one bit set) indicating the last byte written
* a0 = unaligned address of the last *word* written
*
* Furthermore, v0, a3-a5, t11, and t12 are untouched.
@@ -47,9 +47,9 @@
mskqh t1, a1, t3 # e0 :
ornot t1, t2, t2 # .. e1 :
mskql t0, a1, t0 # e0 : assemble the first output word
- cmpbge zero, t2, t7 # .. e1 : bits set iff null found
+ cmpbge zero, t2, t8 # .. e1 : bits set iff null found
or t0, t3, t1 # e0 :
- bne t7, $a_eos # .. e1 :
+ bne t8, $a_eos # .. e1 :
/* On entry to this basic block:
t0 == the first destination word for masking back in
@@ -60,29 +60,29 @@
addq a0, 8, a0 # .. e1 :
ldq_u t1, 0(a1) # e0 :
addq a1, 8, a1 # .. e1 :
- cmpbge zero, t1, t7 # e0 (stall)
- beq t7, $a_loop # .. e1 (zdb)
+ cmpbge zero, t1, t8 # e0 (stall)
+ beq t8, $a_loop # .. e1 (zdb)
/* Take care of the final (partial) word store.
On entry to this basic block we have:
t1 == the source word containing the null
- t7 == the cmpbge mask that found it. */
+ t8 == the cmpbge mask that found it. */
$a_eos:
- negq t7, t6 # e0 : find low bit set
- and t7, t6, t8 # e1 (stall)
+ negq t8, t6 # e0 : find low bit set
+ and t8, t6, t12 # e1 (stall)
/* For the sake of the cache, don't read a destination word
if we're not going to need it. */
- and t8, 0x80, t6 # e0 :
+ and t12, 0x80, t6 # e0 :
bne t6, 1f # .. e1 (zdb)
/* We're doing a partial word store and so need to combine
our source and original destination words. */
ldq_u t0, 0(a0) # e0 :
- subq t8, 1, t6 # .. e1 :
+ subq t12, 1, t6 # .. e1 :
zapnot t1, t6, t1 # e0 : clear src bytes >= null
- or t8, t6, t7 # .. e1 :
- zap t0, t7, t0 # e0 : clear dst bytes <= null
+ or t12, t6, t8 # .. e1 :
+ zap t0, t8, t0 # e0 : clear dst bytes <= null
or t0, t1, t1 # e1 :
1: stq_u t1, 0(a0) # e0 :
@@ -138,14 +138,14 @@
or t0, t1, t1 # e1 :
or t1, t6, t6 # e0 :
- cmpbge zero, t6, t7 # .. e1 :
+ cmpbge zero, t6, t8 # .. e1 :
lda t6, -1 # e0 : for masking just below
- bne t7, $u_final # .. e1 :
+ bne t8, $u_final # .. e1 :
mskql t6, a1, t6 # e0 : mask out the bits we have
or t6, t2, t2 # e1 : already extracted before
- cmpbge zero, t2, t7 # e0 : testing eos
- bne t7, $u_late_head_exit # .. e1 (zdb)
+ cmpbge zero, t2, t8 # e0 : testing eos
+ bne t8, $u_late_head_exit # .. e1 (zdb)
/* Finally, we've got all the stupid leading edge cases taken care
of and we can set up to enter the main loop. */
@@ -155,9 +155,9 @@
extql t2, a1, t0 # e0 : position ho-bits of lo word
ldq_u t2, 8(a1) # .. e1 : read next high-order source word
addq a1, 8, a1 # e0 :
- cmpbge zero, t2, t7 # .. e1 :
+ cmpbge zero, t2, t8 # .. e1 :
nop # e0 :
- bne t7, $u_eos # .. e1 :
+ bne t8, $u_eos # .. e1 :
/* Unaligned copy main loop. In order to avoid reading too much,
the loop is structured to detect zeros in aligned source words.
@@ -182,8 +182,8 @@
ldq_u t2, 0(a1) # .. e1 : load high word for next time
stq_u t1, -8(a0) # e0 : save the current word
mov t3, t0 # .. e1 :
- cmpbge zero, t2, t7 # e0 : test new word for eos
- beq t7, $u_loop # .. e1 :
+ cmpbge zero, t2, t8 # e0 : test new word for eos
+ beq t8, $u_loop # .. e1 :
/* We've found a zero somewhere in the source word we just read.
If it resides in the lower half, we have one (probably partial)
@@ -197,31 +197,31 @@
extqh t2, a1, t1 # e0 :
or t0, t1, t1 # e1 : first (partial) source word complete
- cmpbge zero, t1, t7 # e0 : is the null in this first bit?
- bne t7, $u_final # .. e1 (zdb)
+ cmpbge zero, t1, t8 # e0 : is the null in this first bit?
+ bne t8, $u_final # .. e1 (zdb)
$u_late_head_exit:
stq_u t1, 0(a0) # e0 : the null was in the high-order bits
addq a0, 8, a0 # .. e1 :
extql t2, a1, t1 # e0 :
- cmpbge zero, t1, t7 # .. e1 :
+ cmpbge zero, t1, t8 # .. e1 :
/* Take care of a final (probably partial) result word.
On entry to this basic block:
t1 == assembled source word
- t7 == cmpbge mask that found the null. */
+ t8 == cmpbge mask that found the null. */
$u_final:
- negq t7, t6 # e0 : isolate low bit set
- and t6, t7, t8 # e1 :
+ negq t8, t6 # e0 : isolate low bit set
+ and t6, t8, t12 # e1 :
- and t8, 0x80, t6 # e0 : avoid dest word load if we can
+ and t12, 0x80, t6 # e0 : avoid dest word load if we can
bne t6, 1f # .. e1 (zdb)
ldq_u t0, 0(a0) # e0 :
- subq t8, 1, t6 # .. e1 :
- or t6, t8, t7 # e0 :
+ subq t12, 1, t6 # .. e1 :
+ or t6, t12, t8 # e0 :
zapnot t1, t6, t1 # .. e1 : kill source bytes >= null
- zap t0, t7, t0 # e0 : kill dest bytes <= null
+ zap t0, t8, t0 # e0 : kill dest bytes <= null
or t0, t1, t1 # e1 :
1: stq_u t1, 0(a0) # e0 :
@@ -251,15 +251,15 @@
/* If source misalignment is larger than dest misalignment, we need
extra startup checks to avoid SEGV. */
- cmplt t4, t5, t8 # e0 :
- beq t8, $u_head # .. e1 (zdb)
+ cmplt t4, t5, t12 # e0 :
+ beq t12, $u_head # .. e1 (zdb)
lda t2, -1 # e1 : mask out leading garbage in source
mskqh t2, t5, t2 # e0 :
nop # e0 :
ornot t1, t2, t3 # .. e1 :
- cmpbge zero, t3, t7 # e0 : is there a zero?
- beq t7, $u_head # .. e1 (zdb)
+ cmpbge zero, t3, t8 # e0 : is there a zero?
+ beq t8, $u_head # .. e1 (zdb)
/* At this point we've found a zero in the first partial word of
the source. We need to isolate the valid source data and mask
@@ -268,14 +268,14 @@
ldq_u t0, 0(a0) # e0 :
- negq t7, t6 # .. e1 : build bitmask of bytes <= zero
- and t6, t7, t8 # e0 :
+ negq t8, t6 # .. e1 : build bitmask of bytes <= zero
+ and t6, t8, t12 # e0 :
and a1, 7, t5 # .. e1 :
- subq t8, 1, t6 # e0 :
- or t6, t8, t7 # e1 :
- srl t8, t5, t8 # e0 : adjust final null return value
+ subq t12, 1, t6 # e0 :
+ or t6, t12, t8 # e1 :
+ srl t12, t5, t12 # e0 : adjust final null return value
- zapnot t2, t7, t2 # .. e1 : prepare source word; mirror changes
+ zapnot t2, t8, t2 # .. e1 : prepare source word; mirror changes
and t1, t2, t1 # e1 : to source validity mask
extql t2, a1, t2 # .. e0 :
extql t1, a1, t1 # e0 :
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov