[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #10 from bernds at gcc dot gnu dot org 2010-07-22 20:02 --- Huh, I thought I'd replied to this weeks ago - probably wasn't logged in. Reload can't determine the required structure of a memory address from a predicate name, so it ignores predicates and only looks at constraints. One way of fixing this might be to make the mem explicit in the pattern, and require a register_operand as its address. It might also work to keep the memory_operand but add a constraint that only allows single-reg addresses; if that fails as you say maybe you need to define secondary reloads for it? Can't tell for sure without seeing the code and the failure. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #9 from ebotcazou at gcc dot gnu dot org 2010-06-24 11:06 --- > The memory_reg_operand predicate checks this and fails if it is not a memory > with a single reg, but apparently there is no constraint letter that would > require the same. So, either we need to add a new constraint letter for > memory > that satisfies memory_reg_operand, or find out why predicate hasn't been > consulted. Adding a new constraint letter yields reload failures, presumably because reload doesn't know how to go from MEM[reg+offset] to MEM[reg] on its own. Bernd, are you really sure the predicate can be bypassed like that? -- ebotcazou at gcc dot gnu dot org changed: What|Removed |Added CC|ebotcazou at gcc dot gnu dot| |org | http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #8 from jakub at gcc dot gnu dot org 2010-06-24 10:57 --- The cas/casx insns only allow (mem (reg)) addressing: (match_operand:I48MODE 1 "memory_reg_operand" "+m") (match_operand:DI 1 "memory_reg_operand" "+m") The memory_reg_operand predicate checks this and fails if it is not a memory with a single reg, but apparently there is no constraint letter that would require the same. So, either we need to add a new constraint letter for memory that satisfies memory_reg_operand, or find out why predicate hasn't been consulted. -- jakub at gcc dot gnu dot org changed: What|Removed |Added CC||ebotcazou at gcc dot gnu dot ||org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #7 from bernds at gcc dot gnu dot org 2010-06-11 21:32 --- This would appear to be a bug in the sparc backend then; my patch is only exposing it. I'll not investigate further and leave this for a Sparc maintainer since I have no clue about the machine. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #6 from ebotcazou at gcc dot gnu dot org 2010-06-11 21:30 --- Investigating. -- ebotcazou at gcc dot gnu dot org changed: What|Removed |Added AssignedTo|unassigned at gcc dot gnu |ebotcazou at gcc dot gnu dot |dot org |org Status|UNCONFIRMED |ASSIGNED Ever Confirmed|0 |1 Last reconfirmed|-00-00 00:00:00 |2010-06-11 21:30:34 date|| http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #5 from ebotcazou at gcc dot gnu dot org 2010-06-11 21:29 --- *** Bug 44494 has been marked as a duplicate of this bug. *** -- ebotcazou at gcc dot gnu dot org changed: What|Removed |Added CC||ro at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #4 from mikpe at it dot uu dot se 2010-06-11 21:27 --- The bug is easily observed with a cross to sparc64-linux, using e.g. the task-2.c test case in libgomp's libgomp.c test suite. Diffing the -S output of 4.6-20100605 vanilla (bad) with the same where r160260 has been reverted (ok), we see: --- task-2.s-bad2010-06-11 22:45:02.0 +0200 +++ task-2.s-ok 2010-06-11 22:51:56.0 +0200 @@ -5,20 +5,21 @@ .proc 020 f2._omp_fn.1: .register %g2, #scratch + .register %g3, #scratch add %sp, -192, %sp lduw[%o0+12], %g1 st %g1, [%sp+2235] lduw[%o0+8], %g2 cmp %g2, 10 bne,pt %icc, .LL7 -nop +add%sp, 2235, %g3 ba,pt %xcc, .LL9 sub%sp, -192, %sp .LL5: .LL7: membar 15 add %g1, 1, %g2 - cas [%sp+2235], %g1, %g2 + cas [%g3], %g1, %g2 cmp %g1, %g2 bne,pt %icc, .LL5 mov%g2, %g1 So what r160260 did was to replace [%g3] in the cas instruction with [%sp+2235], which doesn't work because cas cannot use [reg+offset] addressing modes, it only accepts [reg] addressing modes. Attempting to assemble these files confirms: > sparc64-unknown-linux-as task-2.s-ok > sparc64-unknown-linux-as task-2.s-bad task-2.s-bad: Assembler messages: task-2.s-bad:21: Error: Illegal operands task-2.s-bad:48: Error: Illegal operands To compile task-2.c I used sparc64-unknown-linux-gcc -mcpu=v9 -fmessage-length=0 -fopenmp -O2 -S task-2.c (the -mcpu=v9 may be redundant, but that's what the libgomp test suite did on the actual sparc64 box). My sparc64 cross is configured simply with --target=sparc64-unknown-linux --enable-languages=c. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #3 from mikpe at it dot uu dot se 2010-06-11 21:10 --- Created an attachment (id=20898) --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20898&action=view) working -S output from gcc-4.6-20100605 with r160260 reverted -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #2 from mikpe at it dot uu dot se 2010-06-11 21:09 --- Created an attachment (id=20897) --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20897&action=view) broken -S output from gcc-4.6-20100605 -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
--- Comment #1 from mikpe at it dot uu dot se 2010-06-11 21:07 --- Created an attachment (id=20896) --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20896&action=view) task-2.c test case from libgomp's test suite -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
[Bug rtl-optimization/44484] [4.6 regression] revision 160260 caused sparc64 testsuite failures
-- rguenth at gcc dot gnu dot org changed: What|Removed |Added Target Milestone|--- |4.6.0 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44484
