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[src/trunk]: src/sys/arch/sparc/sparc remove obsolete ovbcopy(). it may be t...
details: https://anonhg.NetBSD.org/src/rev/fc25e61f0348
branches: trunk
changeset: 831204:fc25e61f0348
user: mrg <mrg%NetBSD.org@localhost>
date: Fri Mar 16 09:29:24 2018 +0000
description:
remove obsolete ovbcopy(). it may be the very slightly bit
faster for larger copies, but slower for smaller ones.
i don't see any major benefit in keeping this code.
this is the final ovbcopy() reference in src. you're welcome :-)
diffstat:
sys/arch/sparc/sparc/locore.s | 161 +-----------------------------------------
1 files changed, 1 insertions(+), 160 deletions(-)
diffs (182 lines):
diff -r ce0339b05c82 -r fc25e61f0348 sys/arch/sparc/sparc/locore.s
--- a/sys/arch/sparc/sparc/locore.s Fri Mar 16 08:48:34 2018 +0000
+++ b/sys/arch/sparc/sparc/locore.s Fri Mar 16 09:29:24 2018 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: locore.s,v 1.269 2017/11/25 04:11:37 maya Exp $ */
+/* $NetBSD: locore.s,v 1.270 2018/03/16 09:29:24 mrg Exp $ */
/*
* Copyright (c) 1996 Paul Kranenburg
@@ -5331,7 +5331,6 @@
ENTRY(bcopy)
cmp %o2, BCOPY_SMALL
-Lbcopy_start:
bge,a Lbcopy_fancy ! if >= this many, go be fancy.
btst 7, %o0 ! (part of being fancy)
@@ -5494,164 +5493,6 @@
1:
retl
stb %o4,[%o1]
-/*
- * ovbcopy(src, dst, len): like bcopy, but regions may overlap.
- */
-ENTRY(ovbcopy)
- cmp %o0, %o1 ! src < dst?
- bgeu Lbcopy_start ! no, go copy forwards as via bcopy
- cmp %o2, BCOPY_SMALL! (check length for doublecopy first)
-
- /*
- * Since src comes before dst, and the regions might overlap,
- * we have to do the copy starting at the end and working backwards.
- */
- add %o2, %o0, %o0 ! src += len
- add %o2, %o1, %o1 ! dst += len
- bge,a Lback_fancy ! if len >= BCOPY_SMALL, go be fancy
- btst 3, %o0
-
- /*
- * Not much to copy, just do it a byte at a time.
- */
- deccc %o2 ! while (--len >= 0)
- bl 1f
- .empty
-0:
- dec %o0 ! *--dst = *--src;
- ldsb [%o0], %o4
- dec %o1
- deccc %o2
- bge 0b
- stb %o4, [%o1]
-1:
- retl
- nop
-
- /*
- * Plenty to copy, try to be optimal.
- * We only bother with word/halfword/byte copies here.
- */
-Lback_fancy:
-! btst 3, %o0 ! done already
- bnz 1f ! if ((src & 3) == 0 &&
- btst 3, %o1 ! (dst & 3) == 0)
- bz,a Lback_words ! goto words;
- dec 4, %o2 ! (done early for word copy)
-
-1:
- /*
- * See if the low bits match.
- */
- xor %o0, %o1, %o3 ! t = src ^ dst;
- btst 1, %o3
- bz,a 3f ! if (t & 1) == 0, can do better
- btst 1, %o0
-
- /*
- * Nope; gotta do byte copy.
- */
-2:
- dec %o0 ! do {
- ldsb [%o0], %o4 ! *--dst = *--src;
- dec %o1
- deccc %o2 ! } while (--len != 0);
- bnz 2b
- stb %o4, [%o1]
- retl
- nop
-
-3:
- /*
- * Can do halfword or word copy, but might have to copy 1 byte first.
- */
-! btst 1, %o0 ! done earlier
- bz,a 4f ! if (src & 1) { /* copy 1 byte */
- btst 2, %o3 ! (done early)
- dec %o0 ! *--dst = *--src;
- ldsb [%o0], %o4
- dec %o1
- stb %o4, [%o1]
- dec %o2 ! len--;
- btst 2, %o3 ! }
-
-4:
- /*
- * See if we can do a word copy ((t&2) == 0).
- */
-! btst 2, %o3 ! done earlier
- bz,a 6f ! if (t & 2) == 0, can do word copy
- btst 2, %o0 ! (src&2, done early)
-
- /*
- * Gotta do halfword copy.
- */
- dec 2, %o2 ! len -= 2;
-5:
- dec 2, %o0 ! do {
- ldsh [%o0], %o4 ! src -= 2;
- dec 2, %o1 ! dst -= 2;
- deccc 2, %o0 ! *(short *)dst = *(short *)src;
- bge 5b ! } while ((len -= 2) >= 0);
- sth %o4, [%o1]
- b Lback_mopb ! goto mop_up_byte;
- btst 1, %o2 ! (len&1, done early)
-
-6:
- /*
- * We can do word copies, but we might have to copy
- * one halfword first.
- */
-! btst 2, %o0 ! done already
- bz 7f ! if (src & 2) {
- dec 4, %o2 ! (len -= 4, done early)
- dec 2, %o0 ! src -= 2, dst -= 2;
- ldsh [%o0], %o4 ! *(short *)dst = *(short *)src;
- dec 2, %o1
- sth %o4, [%o1]
- dec 2, %o2 ! len -= 2;
- ! }
-
-7:
-Lback_words:
- /*
- * Do word copies (backwards), then mop up trailing halfword
- * and byte if any.
- */
-! dec 4, %o2 ! len -= 4, done already
-0: ! do {
- dec 4, %o0 ! src -= 4;
- dec 4, %o1 ! src -= 4;
- ld [%o0], %o4 ! *(int *)dst = *(int *)src;
- deccc 4, %o2 ! } while ((len -= 4) >= 0);
- bge 0b
- st %o4, [%o1]
-
- /*
- * Check for trailing shortword.
- */
- btst 2, %o2 ! if (len & 2) {
- bz,a 1f
- btst 1, %o2 ! (len&1, done early)
- dec 2, %o0 ! src -= 2, dst -= 2;
- ldsh [%o0], %o4 ! *(short *)dst = *(short *)src;
- dec 2, %o1
- sth %o4, [%o1] ! }
- btst 1, %o2
-
- /*
- * Check for trailing byte.
- */
-1:
-Lback_mopb:
-! btst 1, %o2 ! (done already)
- bnz,a 1f ! if (len & 1) {
- ldsb [%o0 - 1], %o4 ! b = src[-1];
- retl
- nop
-1:
- retl ! dst[-1] = b;
- stb %o4, [%o1 - 1] ! }
/*
* kcopy() is exactly like bcopy except that it set pcb_onfault such that
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