From 726978490fe8a26a1343ac314d00dd48924a1799 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 30 Apr 2014 12:57:51 -0700 Subject: Fix v9/64-bit strcmp when string ends in multiple zero bytes. [BZ #16885] * sysdeps/sparc/sparc64/strcmp.S: Fix end comparison handling when multiple zero bytes exist at the end of a string. Reported by Aurelien Jarno * string/test-strcmp.c (check): Add explicit test for situations where there are multiple zero bytes after the first. --- ChangeLog | 10 ++++++++++ string/test-strcmp.c | 28 ++++++++++++++++++++++++++++ sysdeps/sparc/sparc64/strcmp.S | 31 +++++++++++++++++++++++++++++++ 3 files changed, 69 insertions(+) diff --git a/ChangeLog b/ChangeLog index 5246373dda..0d5c6d8db8 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,13 @@ +2014-05-01 David S. Miller + + [BZ #16885] + * sysdeps/sparc/sparc64/strcmp.S: Fix end comparison handling when + multiple zero bytes exist at the end of a string. + Reported by Aurelien Jarno + + * string/test-strcmp.c (check): Add explicit test for situations where + there are multiple zero bytes after the first. + 2014-01-29 H.J. Lu [BZ #16510] diff --git a/string/test-strcmp.c b/string/test-strcmp.c index f186fd6cd9..73101569a0 100644 --- a/string/test-strcmp.c +++ b/string/test-strcmp.c @@ -353,6 +353,34 @@ check (void) FOR_EACH_IMPL (impl, 0) check_result (impl, s1 + i1, s2 + i2, exp_result); } + + /* Test cases where there are multiple zero bytes after the first. */ + + for (size_t i = 0; i < 16 + 1; i++) + { + s1[i] = 0x00; + s2[i] = 0x00; + } + + for (size_t i = 0; i < 16; i++) + { + int exp_result; + + for (int val = 0x01; val < 0x100; val++) + { + for (size_t j = 0; j < i; j++) + { + s1[j] = val; + s2[j] = val; + } + + s2[i] = val; + + exp_result = SIMPLE_STRCMP (s1, s2); + FOR_EACH_IMPL (impl, 0) + check_result (impl, s1, s2, exp_result); + } + } } diff --git a/sysdeps/sparc/sparc64/strcmp.S b/sysdeps/sparc/sparc64/strcmp.S index 386e0abc60..4abf86f297 100644 --- a/sysdeps/sparc/sparc64/strcmp.S +++ b/sysdeps/sparc/sparc64/strcmp.S @@ -121,6 +121,37 @@ ENTRY(strcmp) movleu %xcc, -1, %o0 srlx rTMP1, 7, rTMP1 + /* In order not to be influenced by bytes after the zero byte, we + * have to retain only the highest bit in the mask for the comparison + * with rSTRXOR to work properly. + */ + mov 0, rTMP2 + andcc rTMP1, 0x0100, %g0 + + movne %xcc, 8, rTMP2 + sllx rTMP1, 63 - 16, %o1 + + movrlz %o1, 16, rTMP2 + sllx rTMP1, 63 - 24, %o1 + + movrlz %o1, 24, rTMP2 + sllx rTMP1, 63 - 32, %o1 + + movrlz %o1, 32, rTMP2 + sllx rTMP1, 63 - 40, %o1 + + movrlz %o1, 40, rTMP2 + sllx rTMP1, 63 - 48, %o1 + + movrlz %o1, 48, rTMP2 + sllx rTMP1, 63 - 56, %o1 + + movrlz %o1, 56, rTMP2 + + srlx rTMP1, rTMP2, rTMP1 + + sllx rTMP1, rTMP2, rTMP1 + cmp rTMP1, rSTRXOR retl movgu %xcc, 0, %o0 -- cgit 1.4.1