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PATCH: PR libc/12597: SSE4 strncmp failure
- From: "H.J. Lu" <hongjiu dot lu at intel dot com>
- To: GNU C Library <libc-alpha at sourceware dot org>
- Date: Sun, 20 Mar 2011 21:50:11 -0700
- Subject: PATCH: PR libc/12597: SSE4 strncmp failure
- Reply-to: "H.J. Lu" <hjl dot tools at gmail dot com>
Hi,
SSE4 strcmp doesn't handler page boundary correctly. This patch fixes
it.
H.J.
----
2011-03-20 H.J. Lu <hongjiu.lu@intel.com>
PR libc/12597
* string/test-strncmp.c (do_page_test): New.
(check2): Likewise.
(test_main): Call check2.
* sysdeps/x86_64/multiarch/strcmp.S: Properly cross page boundary.
diff --git a/string/test-strncmp.c b/string/test-strncmp.c
index 3687879..11c681e 100644
--- a/string/test-strncmp.c
+++ b/string/test-strncmp.c
@@ -200,6 +200,27 @@ do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char,
}
static void
+do_page_test (size_t offset1, size_t offset2, char *s2)
+{
+ char *s1;
+ int exp_result;
+
+ if (offset1 >= page_size || offset2 >= page_size)
+ return;
+
+ s1 = (char *) (buf1 + offset1);
+ s2 += offset2;
+
+ exp_result= *s1;
+
+ FOR_EACH_IMPL (impl, 0)
+ {
+ check_result (impl, s1, s2, page_size, -exp_result);
+ check_result (impl, s2, s1, page_size, exp_result);
+ }
+}
+
+static void
do_random_tests (void)
{
size_t i, j, n, align1, align2, pos, len1, len2, size;
@@ -312,6 +333,25 @@ check1 (void)
}
}
+static void
+check2 (void)
+{
+ size_t i;
+ char *s1, *s2;
+
+ s1 = (char *) buf1;
+ for (i = 0; i < page_size - 1; i++)
+ s1[i] = 23;
+ s1[i] = 0;
+
+ s2 = strdup (s1);
+
+ for (i = 0; i < 64; ++i)
+ do_page_test (3990 + i, 2635, s2);
+
+ free (s2);
+}
+
int
test_main (void)
{
@@ -320,6 +360,7 @@ test_main (void)
test_init ();
check1 ();
+ check2 ();
printf ("%23s", "");
FOR_EACH_IMPL (impl, 0)
diff --git a/sysdeps/x86_64/multiarch/strcmp.S b/sysdeps/x86_64/multiarch/strcmp.S
index 1859289..8879855 100644
--- a/sysdeps/x86_64/multiarch/strcmp.S
+++ b/sysdeps/x86_64/multiarch/strcmp.S
@@ -452,6 +452,7 @@ LABEL(loop_ashr_1_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_1_use_sse4_2)
+LABEL(nibble_ashr_1_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $1, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -499,7 +500,7 @@ LABEL(nibble_ashr_1_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $14, %ecx
- ja LABEL(loop_ashr_1_use_sse4_2)
+ ja LABEL(nibble_ashr_1_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -544,6 +545,7 @@ LABEL(loop_ashr_2_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_2_use_sse4_2)
+LABEL(nibble_ashr_2_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $2, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -591,7 +593,7 @@ LABEL(nibble_ashr_2_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $13, %ecx
- ja LABEL(loop_ashr_2_use_sse4_2)
+ ja LABEL(nibble_ashr_2_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -636,6 +638,7 @@ LABEL(loop_ashr_3_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_3_use_sse4_2)
+LABEL(nibble_ashr_3_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $3, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -683,7 +686,7 @@ LABEL(nibble_ashr_3_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $12, %ecx
- ja LABEL(loop_ashr_3_use_sse4_2)
+ ja LABEL(nibble_ashr_3_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -729,6 +732,7 @@ LABEL(loop_ashr_4_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_4_use_sse4_2)
+LABEL(nibble_ashr_4_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $4, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -776,7 +780,7 @@ LABEL(nibble_ashr_4_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $11, %ecx
- ja LABEL(loop_ashr_4_use_sse4_2)
+ ja LABEL(nibble_ashr_4_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -822,6 +826,7 @@ LABEL(loop_ashr_5_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_5_use_sse4_2)
+LABEL(nibble_ashr_5_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $5, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -870,7 +875,7 @@ LABEL(nibble_ashr_5_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $10, %ecx
- ja LABEL(loop_ashr_5_use_sse4_2)
+ ja LABEL(nibble_ashr_5_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -916,6 +921,7 @@ LABEL(loop_ashr_6_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_6_use_sse4_2)
+LABEL(nibble_ashr_6_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $6, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -963,7 +969,7 @@ LABEL(nibble_ashr_6_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $9, %ecx
- ja LABEL(loop_ashr_6_use_sse4_2)
+ ja LABEL(nibble_ashr_6_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1009,6 +1015,7 @@ LABEL(loop_ashr_7_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_7_use_sse4_2)
+LABEL(nibble_ashr_7_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $7, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -1056,7 +1063,7 @@ LABEL(nibble_ashr_7_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $8, %ecx
- ja LABEL(loop_ashr_7_use_sse4_2)
+ ja LABEL(nibble_ashr_7_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1102,6 +1109,7 @@ LABEL(loop_ashr_8_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_8_use_sse4_2)
+LABEL(nibble_ashr_8_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $8, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -1149,7 +1157,7 @@ LABEL(nibble_ashr_8_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $7, %ecx
- ja LABEL(loop_ashr_8_use_sse4_2)
+ ja LABEL(nibble_ashr_8_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1195,6 +1203,7 @@ LABEL(loop_ashr_9_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_9_use_sse4_2)
+LABEL(nibble_ashr_9_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $9, -16(%rdi, %rdx), %xmm0
@@ -1243,7 +1252,7 @@ LABEL(nibble_ashr_9_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $6, %ecx
- ja LABEL(loop_ashr_9_use_sse4_2)
+ ja LABEL(nibble_ashr_9_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1289,6 +1298,7 @@ LABEL(loop_ashr_10_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_10_use_sse4_2)
+LABEL(nibble_ashr_10_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $10, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -1336,7 +1346,7 @@ LABEL(nibble_ashr_10_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $5, %ecx
- ja LABEL(loop_ashr_10_use_sse4_2)
+ ja LABEL(nibble_ashr_10_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1382,6 +1392,7 @@ LABEL(loop_ashr_11_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_11_use_sse4_2)
+LABEL(nibble_ashr_11_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $11, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -1429,7 +1440,7 @@ LABEL(nibble_ashr_11_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $4, %ecx
- ja LABEL(loop_ashr_11_use_sse4_2)
+ ja LABEL(nibble_ashr_11_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1475,6 +1486,7 @@ LABEL(loop_ashr_12_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_12_use_sse4_2)
+LABEL(nibble_ashr_12_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $12, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -1522,7 +1534,7 @@ LABEL(nibble_ashr_12_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $3, %ecx
- ja LABEL(loop_ashr_12_use_sse4_2)
+ ja LABEL(nibble_ashr_12_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1569,6 +1581,7 @@ LABEL(loop_ashr_13_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_13_use_sse4_2)
+LABEL(nibble_ashr_13_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $13, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -1616,7 +1629,7 @@ LABEL(nibble_ashr_13_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $2, %ecx
- ja LABEL(loop_ashr_13_use_sse4_2)
+ ja LABEL(nibble_ashr_13_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1663,6 +1676,7 @@ LABEL(loop_ashr_14_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_14_use_sse4_2)
+LABEL(nibble_ashr_14_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $14, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -1710,7 +1724,7 @@ LABEL(nibble_ashr_14_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $1, %ecx
- ja LABEL(loop_ashr_14_use_sse4_2)
+ ja LABEL(nibble_ashr_14_use_sse4_2_restart)
jmp LABEL(nibble_ashr_use_sse4_2_exit)
@@ -1759,6 +1773,7 @@ LABEL(loop_ashr_15_use_sse4_2):
add $16, %r10
jg LABEL(nibble_ashr_15_use_sse4_2)
+LABEL(nibble_ashr_15_use_sse4_2_restart):
movdqa (%rdi, %rdx), %xmm0
palignr $15, -16(%rdi, %rdx), %xmm0
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L
@@ -1806,7 +1821,7 @@ LABEL(nibble_ashr_15_use_sse4_2):
jae LABEL(nibble_ashr_use_sse4_2_exit)
# endif
cmp $0, %ecx
- ja LABEL(loop_ashr_15_use_sse4_2)
+ ja LABEL(nibble_ashr_15_use_sse4_2_restart)
LABEL(nibble_ashr_use_sse4_2_exit):
# if !defined USE_AS_STRCASECMP_L && !defined USE_AS_STRNCASECMP_L