From fa64b7f76b97930cd2aaf7bfd305cac3d925cd8f Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Thu, 21 May 2009 18:47:59 -0700 Subject: [PATCH] Fix IA-64 memchr read-ahead. The latest stratcliff extension exposed a bug in the IA-64 memchr which uses non-speculative loads to prefetch data. Change the code to use speculative loads with appropriate fixup. Fixes BZ 10162. --- ChangeLog | 5 +++++ sysdeps/ia64/memchr.S | 17 ++++++++++++++++- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/ChangeLog b/ChangeLog index 5746edee24..4247797ee8 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2009-05-21 H.J. Lu + + [BZ #10162] + * sysdeps/ia64/memchr.S: Use speculative load. + 2009-05-21 H.J. Lu * sysdeps/unix/sysv/linux/ia64/____longjmp_chk.S: New file. diff --git a/sysdeps/ia64/memchr.S b/sysdeps/ia64/memchr.S index e9a7ba8230..cd062b2dd5 100644 --- a/sysdeps/ia64/memchr.S +++ b/sysdeps/ia64/memchr.S @@ -96,7 +96,8 @@ ENTRY(__memchr) mov pr.rot = 1 << 16 ;; .l2: (p[0]) mov addr[0] = ret0 -(p[0]) ld8 value[0] = [ret0], 8 +(p[0]) ld8.s value[0] = [ret0], 8 // speculative load +(p[MEMLAT]) chk.s value[MEMLAT], .recovery // check and recovery (p[MEMLAT]) xor aux[0] = value[MEMLAT], chrx8 (p[MEMLAT+1]) czx1.r poschr[0] = aux[1] (p[MEMLAT+2]) cmp.ne p7, p0 = 8, poschr[1] @@ -124,6 +125,20 @@ ENTRY(__memchr) mov ar.lc = saved_lc br.ret.sptk.many b0 +.recovery: + adds ret0 = -((MEMLAT + 1) * 8), ret0;; +(p[MEMLAT+1]) add ret0 = -8, ret0;; +(p[MEMLAT+2]) add ret0 = -8, ret0;; +.l4: + mov addr[MEMLAT+2] = ret0 + ld8 tmp = [ret0];; // load the first unchecked 8byte + xor aux[1] = tmp, chrx8;; + czx1.r poschr[1] = aux[1];; + cmp.ne p7, p0 = 8, poschr[1] +(p7) br.cond.spnt .foundit;; + adds ret0 = 8, ret0 // load the next unchecked 8byte + br.sptk .l4;; + END(__memchr) weak_alias (__memchr, memchr) -- 2.43.5