[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #11 from ebotcazou at gcc dot gnu dot org 2010-09-20 21:46 --- By Jakub. -- ebotcazou at gcc dot gnu dot org changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution||FIXED Target Milestone|--- |4.4.1 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #9 from jakub at gcc dot gnu dot org 2009-07-11 09:23 --- Subject: Bug 40668 Author: jakub Date: Sat Jul 11 09:23:32 2009 New Revision: 149511 URL: http://gcc.gnu.org/viewcvs?root=gccview=revrev=149511 Log: PR target/40668 * function.c (assign_parm_setup_stack): Adjust MEM_OFFSET (data-stack_parm) if promoted_mode is different from nominal_mode on big endian. * gcc.c-torture/execute/pr40668.c: New test. Added: trunk/gcc/testsuite/gcc.c-torture/execute/pr40668.c Modified: trunk/gcc/ChangeLog trunk/gcc/function.c trunk/gcc/testsuite/ChangeLog -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #10 from jakub at gcc dot gnu dot org 2009-07-11 09:26 --- Subject: Bug 40668 Author: jakub Date: Sat Jul 11 09:26:23 2009 New Revision: 149512 URL: http://gcc.gnu.org/viewcvs?root=gccview=revrev=149512 Log: PR target/40668 * function.c (assign_parm_setup_stack): Adjust MEM_OFFSET (data-stack_parm) if promoted_mode is different from nominal_mode on big endian. * gcc.c-torture/execute/pr40668.c: New test. Added: branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/execute/pr40668.c Modified: branches/gcc-4_4-branch/gcc/ChangeLog branches/gcc-4_4-branch/gcc/function.c branches/gcc-4_4-branch/gcc/testsuite/ChangeLog -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #7 from mikpe at it dot uu dot se 2009-07-08 16:43 --- 4.4-20090630 plus this fix bootstrapped fine, fixed the test case, built a working 2.6.31-rc2 Linux kernel, and built a working Erlang VM. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #8 from blp at cs dot stanford dot edu 2009-07-08 17:30 --- Wow, that's amazingly fast turnaround. Thanks so much guys! -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #3 from mikpe at it dot uu dot se 2009-07-07 11:35 --- Confirmed, with gcc-4.3-20090705 it works, with gcc-4.4-20090630 it fails. Compiling with -S and comparing the .s files it looks like 4.4 completely mis-schedules the code for put_uint32: put_uint32: .register %g2, #scratch .register %g3, #scratch ldub[%sp+2175], %g1 ldub[%sp+2176], %g3 ldub[%sp+2177], %g2 ldub[%sp+2178], %g4 st %o0, [%sp+2175] stb %g4, [%o1+3] stb %g1, [%o1] stb %g3, [%o1+1] jmp %o7+8 stb%g2, [%o1+2] Notice how the store of %o0 to the four bytes at %sp+2175 comes after the corresponding byte loads, so %g1 to %g4 are loaded with garbage, likely zeroes. In contrast, gcc-4.3 generates the store before the loads: put_uint32: .register %g2, #scratch .register %g3, #scratch st %o0, [%sp+2175] ldub[%sp+2176], %g3 ldub[%sp+2177], %g4 ldub[%sp+2178], %g2 ldub[%sp+2175], %g1 stb %g2, [%o1+3] stb %g1, [%o1] stb %g3, [%o1+1] jmp %o7+8 stb%g4, [%o1+2] -- mikpe at it dot uu dot se changed: What|Removed |Added CC||mikpe at it dot uu dot se http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #4 from mikpe at it dot uu dot se 2009-07-07 16:28 --- A reghunt identified Jakub's (added to cc: list) r142481 (PR38367 fix) as the source of this regression. -- mikpe at it dot uu dot se changed: What|Removed |Added CC||jakub at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #5 from jakub at gcc dot gnu dot org 2009-07-07 19:05 --- Created an attachment (id=18151) -- (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18151action=view) gcc44-pr40668.patch Untested patch that fixes this testcase. I believe my commit was correct, but apparently it can be modified later on without adjusting MEM_OFFSET. I don't have a working SPARC box around ATM, so I can't bootstrap/regtest it there. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #6 from mikpe at it dot uu dot se 2009-07-07 23:10 --- (In reply to comment #5) Created an attachment (id=18151) -- (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18151action=view) [edit] gcc44-pr40668.patch Untested patch that fixes this testcase. Thanks. This fixes the issue in a cross-compiler to sparc64-linux. I'm currently bootstrapping 4.4-20090630 plus this patch on an Ultra5, I'll follow up once that's complete (it will take quite a while). -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #1 from blp at cs dot stanford dot edu 2009-07-07 05:57 --- Created an attachment (id=18147) -- (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18147action=view) preprocessed test input -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
[Bug target/40668] 64-bit sparc miscompiles memcpy of argument inside switch
--- Comment #2 from blp at cs dot stanford dot edu 2009-07-07 05:58 --- Created an attachment (id=18148) -- (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18148action=view) test program (before preprocessing) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40668
