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From: "hp at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/30665] New: peephole2 misapplied on postinc mem Date: Thu, 01 Feb 2007 11:34:00 -0000 [thread overview] Message-ID: <bug-30665-507@http.gcc.gnu.org/bugzilla/> (raw) This testcase is miscompiled on all versions of GCC (visible on r111226): int __attribute__ ((__noinline__)) f (unsigned *p, int *x) { int y = *p++ & 0xfff; *x++ = y; *x = *p; return y; } int main (void) { unsigned u[2] = { 0xbaad, 0xdad1 }; int x[2] = {17689, 23456}; if (f (u, x) != 0xaad || x[0] != 0xaad || x[1] != 0xdad1) abort (); exit (0); } It's caused by the cris.md peephole2 marked "andu (casesi+45)" allowing post-inc memory in operand 1, effectively "shrinking" the post-inc. The fix is to replace all "(GET_CODE (operands[1]) != MEM || ! MEM_VOLATILE_P (operands[1]))" with "!side_effects_p (operands[1])" everywhere. -- Summary: peephole2 misapplied on postinc mem Product: gcc Version: 3.2.1 Status: UNCONFIRMED Keywords: wrong-code Severity: normal Priority: P3 Component: target AssignedTo: hp at gcc dot gnu dot org ReportedBy: hp at gcc dot gnu dot org GCC target triplet: cris-* http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30665
next reply other threads:[~2007-02-01 11:34 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2007-02-01 11:34 hp at gcc dot gnu dot org [this message] 2007-02-01 11:35 ` [Bug target/30665] " hp at gcc dot gnu dot org 2007-02-05 21:21 ` hp at gcc dot gnu dot org 2007-02-05 21:22 ` hp at gcc dot gnu dot org 2007-02-05 21:44 ` hp at gcc dot gnu dot org
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