sparc32: switch copy_user.S away from range exception table entries

Those were the last range exception table entries, which will allow
to get rid of a lot of weirdness.  Emits the same code into .text.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2020-07-16 10:19:37 -04:00
parent cfd5fa7021
commit c4da8e0dc6

View File

@ -21,98 +21,134 @@
/* Work around cpp -rob */
#define ALLOC #alloc
#define EXECINSTR #execinstr
#define EX_ENTRY(l1, l2) \
.section __ex_table,ALLOC; \
.align 4; \
.word l1, l2; \
.text;
#define EX(x,y,a,b) \
98: x,y; \
.section .fixup,ALLOC,EXECINSTR; \
.align 4; \
99: ba fixupretl; \
a, b, %g3; \
.section __ex_table,ALLOC; \
.align 4; \
.word 98b, 99b; \
.text; \
.align 4
99: retl; \
a, b, %o0; \
EX_ENTRY(98b, 99b)
#define EX2(x,y,c,d,e,a,b) \
98: x,y; \
.section .fixup,ALLOC,EXECINSTR; \
.align 4; \
99: c, d, e; \
ba fixupretl; \
a, b, %g3; \
.section __ex_table,ALLOC; \
.align 4; \
.word 98b, 99b; \
.text; \
.align 4
retl; \
a, b, %o0; \
EX_ENTRY(98b, 99b)
#define EXO2(x,y) \
98: x, y; \
.section __ex_table,ALLOC; \
.align 4; \
.word 98b, 97f; \
.text; \
.align 4
EX_ENTRY(98b, 97f)
#define EXT(start,end,handler) \
.section __ex_table,ALLOC; \
.align 4; \
.word start, 0, end, handler; \
.text; \
.align 4
#define LD(insn, src, offset, reg, label) \
98: insn [%src + (offset)], %reg; \
.section .fixup,ALLOC,EXECINSTR; \
99: ba label; \
mov offset, %g5; \
EX_ENTRY(98b, 99b)
/* Please do not change following macros unless you change logic used
* in .fixup at the end of this file as well
*/
#define ST(insn, dst, offset, reg, label) \
98: insn %reg, [%dst + (offset)]; \
.section .fixup,ALLOC,EXECINSTR; \
99: ba label; \
mov offset, %g5; \
EX_ENTRY(98b, 99b)
/* Both these macros have to start with exactly the same insn */
/* left: g7 + (g1 % 128) - offset */
#define MOVE_BIGCHUNK(src, dst, offset, t0, t1, t2, t3, t4, t5, t6, t7) \
ldd [%src + (offset) + 0x00], %t0; \
ldd [%src + (offset) + 0x08], %t2; \
ldd [%src + (offset) + 0x10], %t4; \
ldd [%src + (offset) + 0x18], %t6; \
st %t0, [%dst + (offset) + 0x00]; \
st %t1, [%dst + (offset) + 0x04]; \
st %t2, [%dst + (offset) + 0x08]; \
st %t3, [%dst + (offset) + 0x0c]; \
st %t4, [%dst + (offset) + 0x10]; \
st %t5, [%dst + (offset) + 0x14]; \
st %t6, [%dst + (offset) + 0x18]; \
st %t7, [%dst + (offset) + 0x1c];
LD(ldd, src, offset + 0x00, t0, bigchunk_fault) \
LD(ldd, src, offset + 0x08, t2, bigchunk_fault) \
LD(ldd, src, offset + 0x10, t4, bigchunk_fault) \
LD(ldd, src, offset + 0x18, t6, bigchunk_fault) \
ST(st, dst, offset + 0x00, t0, bigchunk_fault) \
ST(st, dst, offset + 0x04, t1, bigchunk_fault) \
ST(st, dst, offset + 0x08, t2, bigchunk_fault) \
ST(st, dst, offset + 0x0c, t3, bigchunk_fault) \
ST(st, dst, offset + 0x10, t4, bigchunk_fault) \
ST(st, dst, offset + 0x14, t5, bigchunk_fault) \
ST(st, dst, offset + 0x18, t6, bigchunk_fault) \
ST(st, dst, offset + 0x1c, t7, bigchunk_fault)
/* left: g7 + (g1 % 128) - offset */
#define MOVE_BIGALIGNCHUNK(src, dst, offset, t0, t1, t2, t3, t4, t5, t6, t7) \
ldd [%src + (offset) + 0x00], %t0; \
ldd [%src + (offset) + 0x08], %t2; \
ldd [%src + (offset) + 0x10], %t4; \
ldd [%src + (offset) + 0x18], %t6; \
std %t0, [%dst + (offset) + 0x00]; \
std %t2, [%dst + (offset) + 0x08]; \
std %t4, [%dst + (offset) + 0x10]; \
std %t6, [%dst + (offset) + 0x18];
LD(ldd, src, offset + 0x00, t0, bigchunk_fault) \
LD(ldd, src, offset + 0x08, t2, bigchunk_fault) \
LD(ldd, src, offset + 0x10, t4, bigchunk_fault) \
LD(ldd, src, offset + 0x18, t6, bigchunk_fault) \
ST(std, dst, offset + 0x00, t0, bigchunk_fault) \
ST(std, dst, offset + 0x08, t2, bigchunk_fault) \
ST(std, dst, offset + 0x10, t4, bigchunk_fault) \
ST(std, dst, offset + 0x18, t6, bigchunk_fault)
.section .fixup,#alloc,#execinstr
bigchunk_fault:
sub %g7, %g5, %o0
and %g1, 127, %g1
retl
add %o0, %g1, %o0
/* left: offset + 16 + (g1 % 16) */
#define MOVE_LASTCHUNK(src, dst, offset, t0, t1, t2, t3) \
ldd [%src - (offset) - 0x10], %t0; \
ldd [%src - (offset) - 0x08], %t2; \
st %t0, [%dst - (offset) - 0x10]; \
st %t1, [%dst - (offset) - 0x0c]; \
st %t2, [%dst - (offset) - 0x08]; \
st %t3, [%dst - (offset) - 0x04];
LD(ldd, src, -(offset + 0x10), t0, lastchunk_fault) \
LD(ldd, src, -(offset + 0x08), t2, lastchunk_fault) \
ST(st, dst, -(offset + 0x10), t0, lastchunk_fault) \
ST(st, dst, -(offset + 0x0c), t1, lastchunk_fault) \
ST(st, dst, -(offset + 0x08), t2, lastchunk_fault) \
ST(st, dst, -(offset + 0x04), t3, lastchunk_fault)
.section .fixup,#alloc,#execinstr
lastchunk_fault:
and %g1, 15, %g1
retl
sub %g1, %g5, %o0
/* left: o3 + (o2 % 16) - offset */
#define MOVE_HALFCHUNK(src, dst, offset, t0, t1, t2, t3) \
lduh [%src + (offset) + 0x00], %t0; \
lduh [%src + (offset) + 0x02], %t1; \
lduh [%src + (offset) + 0x04], %t2; \
lduh [%src + (offset) + 0x06], %t3; \
sth %t0, [%dst + (offset) + 0x00]; \
sth %t1, [%dst + (offset) + 0x02]; \
sth %t2, [%dst + (offset) + 0x04]; \
sth %t3, [%dst + (offset) + 0x06];
LD(lduh, src, offset + 0x00, t0, halfchunk_fault) \
LD(lduh, src, offset + 0x02, t1, halfchunk_fault) \
LD(lduh, src, offset + 0x04, t2, halfchunk_fault) \
LD(lduh, src, offset + 0x06, t3, halfchunk_fault) \
ST(sth, dst, offset + 0x00, t0, halfchunk_fault) \
ST(sth, dst, offset + 0x02, t1, halfchunk_fault) \
ST(sth, dst, offset + 0x04, t2, halfchunk_fault) \
ST(sth, dst, offset + 0x06, t3, halfchunk_fault)
/* left: o3 + (o2 % 16) + offset + 2 */
#define MOVE_SHORTCHUNK(src, dst, offset, t0, t1) \
ldub [%src - (offset) - 0x02], %t0; \
ldub [%src - (offset) - 0x01], %t1; \
stb %t0, [%dst - (offset) - 0x02]; \
stb %t1, [%dst - (offset) - 0x01];
LD(ldub, src, -(offset + 0x02), t0, halfchunk_fault) \
LD(ldub, src, -(offset + 0x01), t1, halfchunk_fault) \
ST(stb, dst, -(offset + 0x02), t0, halfchunk_fault) \
ST(stb, dst, -(offset + 0x01), t1, halfchunk_fault)
.section .fixup,#alloc,#execinstr
halfchunk_fault:
and %o2, 15, %o2
sub %o3, %g5, %o3
retl
add %o2, %o3, %o0
/* left: offset + 2 + (o2 % 2) */
#define MOVE_LAST_SHORTCHUNK(src, dst, offset, t0, t1) \
LD(ldub, src, -(offset + 0x02), t0, last_shortchunk_fault) \
LD(ldub, src, -(offset + 0x01), t1, last_shortchunk_fault) \
ST(stb, dst, -(offset + 0x02), t0, last_shortchunk_fault) \
ST(stb, dst, -(offset + 0x01), t1, last_shortchunk_fault)
.section .fixup,#alloc,#execinstr
last_shortchunk_fault:
and %o2, 1, %o2
retl
sub %o2, %g5, %o0
.text
.align 4
@ -182,8 +218,6 @@ __copy_user: /* %o0=dst %o1=src %o2=len */
MOVE_BIGCHUNK(o1, o0, 0x20, o2, o3, o4, o5, g2, g3, g4, g5)
MOVE_BIGCHUNK(o1, o0, 0x40, o2, o3, o4, o5, g2, g3, g4, g5)
MOVE_BIGCHUNK(o1, o0, 0x60, o2, o3, o4, o5, g2, g3, g4, g5)
80:
EXT(5b, 80b, 50f)
subcc %g7, 128, %g7
add %o1, 128, %o1
bne 5b
@ -201,7 +235,6 @@ __copy_user: /* %o0=dst %o1=src %o2=len */
jmpl %o5 + %lo(copy_user_table_end), %g0
add %o0, %g7, %o0
copy_user_table:
MOVE_LASTCHUNK(o1, o0, 0x60, g2, g3, g4, g5)
MOVE_LASTCHUNK(o1, o0, 0x50, g2, g3, g4, g5)
MOVE_LASTCHUNK(o1, o0, 0x40, g2, g3, g4, g5)
@ -210,7 +243,6 @@ copy_user_table:
MOVE_LASTCHUNK(o1, o0, 0x10, g2, g3, g4, g5)
MOVE_LASTCHUNK(o1, o0, 0x00, g2, g3, g4, g5)
copy_user_table_end:
EXT(copy_user_table, copy_user_table_end, 51f)
be copy_user_last7
andcc %g1, 4, %g0
@ -250,8 +282,6 @@ ldd_std:
MOVE_BIGALIGNCHUNK(o1, o0, 0x20, o2, o3, o4, o5, g2, g3, g4, g5)
MOVE_BIGALIGNCHUNK(o1, o0, 0x40, o2, o3, o4, o5, g2, g3, g4, g5)
MOVE_BIGALIGNCHUNK(o1, o0, 0x60, o2, o3, o4, o5, g2, g3, g4, g5)
81:
EXT(ldd_std, 81b, 52f)
subcc %g7, 128, %g7
add %o1, 128, %o1
bne ldd_std
@ -290,8 +320,6 @@ cannot_optimize:
10:
MOVE_HALFCHUNK(o1, o0, 0x00, g2, g3, g4, g5)
MOVE_HALFCHUNK(o1, o0, 0x08, g2, g3, g4, g5)
82:
EXT(10b, 82b, 53f)
subcc %o3, 0x10, %o3
add %o1, 0x10, %o1
bne 10b
@ -308,8 +336,6 @@ byte_chunk:
MOVE_SHORTCHUNK(o1, o0, -0x0c, g2, g3)
MOVE_SHORTCHUNK(o1, o0, -0x0e, g2, g3)
MOVE_SHORTCHUNK(o1, o0, -0x10, g2, g3)
83:
EXT(byte_chunk, 83b, 54f)
subcc %o3, 0x10, %o3
add %o1, 0x10, %o1
bne byte_chunk
@ -325,16 +351,14 @@ short_end:
add %o1, %o3, %o1
jmpl %o5 + %lo(short_table_end), %g0
andcc %o2, 1, %g0
84:
MOVE_SHORTCHUNK(o1, o0, 0x0c, g2, g3)
MOVE_SHORTCHUNK(o1, o0, 0x0a, g2, g3)
MOVE_SHORTCHUNK(o1, o0, 0x08, g2, g3)
MOVE_SHORTCHUNK(o1, o0, 0x06, g2, g3)
MOVE_SHORTCHUNK(o1, o0, 0x04, g2, g3)
MOVE_SHORTCHUNK(o1, o0, 0x02, g2, g3)
MOVE_SHORTCHUNK(o1, o0, 0x00, g2, g3)
MOVE_LAST_SHORTCHUNK(o1, o0, 0x0c, g2, g3)
MOVE_LAST_SHORTCHUNK(o1, o0, 0x0a, g2, g3)
MOVE_LAST_SHORTCHUNK(o1, o0, 0x08, g2, g3)
MOVE_LAST_SHORTCHUNK(o1, o0, 0x06, g2, g3)
MOVE_LAST_SHORTCHUNK(o1, o0, 0x04, g2, g3)
MOVE_LAST_SHORTCHUNK(o1, o0, 0x02, g2, g3)
MOVE_LAST_SHORTCHUNK(o1, o0, 0x00, g2, g3)
short_table_end:
EXT(84b, short_table_end, 55f)
be 1f
nop
EX(ldub [%o1], %g2, add %g0, 1)
@ -363,123 +387,8 @@ short_aligned_end:
.section .fixup,#alloc,#execinstr
.align 4
97:
mov %o2, %g3
fixupretl:
retl
mov %g3, %o0
/* exception routine sets %g2 to (broken_insn - first_insn)>>2 */
50:
/* This magic counts how many bytes are left when crash in MOVE_BIGCHUNK
* happens. This is derived from the amount ldd reads, st stores, etc.
* x = g2 % 12;
* g3 = g1 + g7 - ((g2 / 12) * 32 + (x < 4) ? 0 : (x - 4) * 4);
* o0 += (g2 / 12) * 32;
*/
cmp %g2, 12
add %o0, %g7, %o0
bcs 1f
cmp %g2, 24
bcs 2f
cmp %g2, 36
bcs 3f
nop
sub %g2, 12, %g2
sub %g7, 32, %g7
3: sub %g2, 12, %g2
sub %g7, 32, %g7
2: sub %g2, 12, %g2
sub %g7, 32, %g7
1: cmp %g2, 4
bcs,a 60f
clr %g2
sub %g2, 4, %g2
sll %g2, 2, %g2
60: and %g1, 0x7f, %g3
sub %o0, %g7, %o0
add %g3, %g7, %g3
ba fixupretl
sub %g3, %g2, %g3
51:
/* i = 41 - g2; j = i % 6;
* g3 = (g1 & 15) + (i / 6) * 16 + (j < 4) ? (j + 1) * 4 : 16;
* o0 -= (i / 6) * 16 + 16;
*/
neg %g2
and %g1, 0xf, %g1
add %g2, 41, %g2
add %o0, %g1, %o0
1: cmp %g2, 6
bcs,a 2f
cmp %g2, 4
add %g1, 16, %g1
b 1b
sub %g2, 6, %g2
2: bcc,a 2f
mov 16, %g2
inc %g2
sll %g2, 2, %g2
2: add %g1, %g2, %g3
ba fixupretl
sub %o0, %g3, %o0
52:
/* g3 = g1 + g7 - (g2 / 8) * 32 + (g2 & 4) ? (g2 & 3) * 8 : 0;
o0 += (g2 / 8) * 32 */
andn %g2, 7, %g4
add %o0, %g7, %o0
andcc %g2, 4, %g0
and %g2, 3, %g2
sll %g4, 2, %g4
sll %g2, 3, %g2
bne 60b
sub %g7, %g4, %g7
ba 60b
clr %g2
53:
/* g3 = o3 + (o2 & 15) - (g2 & 8) - (g2 & 4) ? (g2 & 3) * 2 : 0;
o0 += (g2 & 8) */
and %g2, 3, %g4
andcc %g2, 4, %g0
and %g2, 8, %g2
sll %g4, 1, %g4
be 1f
add %o0, %g2, %o0
add %g2, %g4, %g2
1: and %o2, 0xf, %g3
add %g3, %o3, %g3
ba fixupretl
sub %g3, %g2, %g3
54:
/* g3 = o3 + (o2 & 15) - (g2 / 4) * 2 - (g2 & 2) ? (g2 & 1) : 0;
o0 += (g2 / 4) * 2 */
srl %g2, 2, %o4
and %g2, 1, %o5
srl %g2, 1, %g2
add %o4, %o4, %o4
and %o5, %g2, %o5
and %o2, 0xf, %o2
add %o0, %o4, %o0
sub %o3, %o5, %o3
sub %o2, %o4, %o2
ba fixupretl
add %o2, %o3, %g3
55:
/* i = 27 - g2;
g3 = (o2 & 1) + i / 4 * 2 + !(i & 3);
o0 -= i / 4 * 2 + 1 */
neg %g2
and %o2, 1, %o2
add %g2, 27, %g2
srl %g2, 2, %o5
andcc %g2, 3, %g0
mov 1, %g2
add %o5, %o5, %o5
be,a 1f
clr %g2
1: add %g2, %o5, %g3
sub %o0, %g3, %o0
ba fixupretl
add %g3, %o2, %g3
mov %o2, %o0
.globl __copy_user_end
__copy_user_end: