| Message ID | 564F42CC.8090609@mentor.com |
|---|---|
| State | New |
| Headers | show |
On Fri, Nov 20, 2015 at 4:57 PM, Tom de Vries <Tom_deVries@mentor.com> wrote: > [ was: Re: [PATCH] Fix parloops gimple_uid usage ] > > On 09/10/15 23:09, Tom de Vries wrote: >> >> @@ -2392,6 +2397,9 @@ gather_scalar_reductions (loop_p loop, >> reduction_info_table_type *reduction_list >> loop_vec_info simple_inner_loop_info = NULL; >> bool allow_double_reduc = true; >> >> + if (!stmt_vec_info_vec.exists ()) >> + init_stmt_vec_info_vec (); >> + >> simple_loop_info = vect_analyze_loop_form (loop); >> if (simple_loop_info == NULL) >> return; >> @@ -2453,9 +2461,16 @@ gather_scalar_reductions (loop_p loop, >> reduction_info_table_type *reduction_list >> destroy_loop_vec_info (simple_loop_info, true); >> destroy_loop_vec_info (simple_inner_loop_info, true); >> >> + /* Release the claim on gimple_uid. */ >> + free_stmt_vec_info_vec (); >> + > > > With the src/libgomp/testsuite/libgomp.c/pr46886.c testcase, compiled in > addition with -ftree-vectorize, I ran into an ICE: > ... > src/libgomp/testsuite/libgomp.c/pr46886.c:8:5: internal compiler error: in > init_stmt_vec_info_vec, at tree-vect-stmts.c:8250 > int foo (void) > ^~~ > > 0x1196082 init_stmt_vec_info_vec() > src/gcc/tree-vect-stmts.c:8250 > 0x11c3ed4 vectorize_loops() > src/gcc/tree-vectorizer.c:510 > 0x10a7ea5 execute > src/gcc/tree-ssa-loop.c:276 > ... > > The ICE is caused by the fact that init_stmt_vec_info_vec is called at the > start of vectorize_loops, while stmt_vec_info_vec is not empty. I traced > this back to gather_scalar_reduction, where we call init_stmt_vec_info_vec, > but we skip free_stmt_vec_info_vec if we take the early-out for > simple_loop_info == NULL. > > This patch fixes the ICE by making sure we always call > free_stmt_vec_info_vec in gather_scalar_reduction. > > Passes cc1/f951 rebuild and autopar testing. > > OK for stage3 trunk if bootstrap and regtest succeeds? Ok. Richard. > Thanks, > - Tom
Always call free_stmt_vec_info_vec in gather_scalar_reductions 2015-11-20 Tom de Vries <tom@codesourcery.com> PR tree-optimization/68460 * tree-parloops.c (gather_scalar_reductions): Also call free_stmt_vec_info_vec if simple_loop_info == NULL. * gcc.dg/autopar/pr68460.c: New test. --- gcc/testsuite/gcc.dg/autopar/pr68460.c | 35 ++++++++++++++++++++++++++++++++++ gcc/tree-parloops.c | 6 +++++- 2 files changed, 40 insertions(+), 1 deletion(-) diff --git a/gcc/testsuite/gcc.dg/autopar/pr68460.c b/gcc/testsuite/gcc.dg/autopar/pr68460.c new file mode 100644 index 0000000..0c00065 --- /dev/null +++ b/gcc/testsuite/gcc.dg/autopar/pr68460.c @@ -0,0 +1,35 @@ +/* { dg-do "compile" } */ +/* { dg-options "-O -ftree-parallelize-loops=2 -ftree-vectorize -fno-tree-ch -fno-tree-dominator-opts" } */ + +void abort (void); + +int d[1024], e[1024]; + +int +foo (void) +{ + int s = 0; + int i; + + for (i = 0; i < 1024; i++) + s += d[i] - e[i]; + + return s; +} + +int +main () +{ + int i; + + for (i = 0; i < 1024; i++) + { + d[i] = i * 2; + e[i] = i; + } + + if (foo () != 1023 * 1024 / 2) + abort (); + + return 0; +} diff --git a/gcc/tree-parloops.c b/gcc/tree-parloops.c index 8d7912d..85cc78d 100644 --- a/gcc/tree-parloops.c +++ b/gcc/tree-parloops.c @@ -2433,7 +2433,7 @@ gather_scalar_reductions (loop_p loop, reduction_info_table_type *reduction_list simple_loop_info = vect_analyze_loop_form (loop); if (simple_loop_info == NULL) - return; + goto gather_done; for (gsi = gsi_start_phis (loop->header); !gsi_end_p (gsi); gsi_next (&gsi)) { @@ -2492,9 +2492,13 @@ gather_scalar_reductions (loop_p loop, reduction_info_table_type *reduction_list destroy_loop_vec_info (simple_loop_info, true); destroy_loop_vec_info (simple_inner_loop_info, true); + gather_done: /* Release the claim on gimple_uid. */ free_stmt_vec_info_vec (); + if (reduction_list->elements () == 0) + return; + /* As gimple_uid is used by the vectorizer in between vect_analyze_loop_form and free_stmt_vec_info_vec, we can set gimple_uid of reduc_phi stmts only now. */