Richard Guenther wrote:
> In this testcase the alignment of arr[i] should be irrelevant - it is
> not part of
> the stmts that are going to be vectorized. But of course this may be
> simply an odering issue in how we analyze data-references / statements
> in basic-block vectorization (thus we possibly did not yet declare the
> arr[i] = i statement as not taking part in the vectorization).
The following patch changes tree-vect-data-refs.c:vect_verify_datarefs_alignment
to only take into account statements marked as "relevant".
This should have no impact for loop-based vectorization, since the only caller
(vect_enhance_data_refs_alignment) already skips irrelevant statements.
[ As an aside, that routine should probably use STMT_VINFO_RELEVANT_P instead
of just checking STMT_VINFO_RELEVANT as a boolean. ]
However, for SLP this change in itself doesn't work, since vect_slp_analyze_bb_1
calls vect_verify_datarefs_alignment *before* statements have actually been
marked as relevant or irrelevant. Therefore, the patch also rearranges the
sequence in vect_slp_analyze_bb_1.
This in turn caused ICEs in vect_get_store_cost/vect_get_load_cost, since those
now can get called with statements with unsupported alignment. There is already
one caller (vect_get_data_access_cost) that checks for this case and simply
returns "infinite" cost instead of aborting. The patch moves this behaviour
into vect_get_store_cost/vect_get_load_cost themselves. (The particular cost
shouldn't matter since vectorization will still be rejected in the end, it's
just that the test now runs a bit later.)
Overall, I've tested the patch with no regresions on powerpc64-linux and
arm-linux-gnueabi. On PowerPC, it fixed the gcc.dg/vect/bb-slp-16.c test.
Mikael, would you mind verifying that it fixes the problem on sparc64?
OK for mainline?
Bye,
Ulrich
ChangeLog:
PR tree-optimization/53729
PR tree-optimization/53636
* tree-vect-slp.c (vect_slp_analyze_bb_1): Delay call to
vect_verify_datarefs_alignment until after statements have
been marked as relevant/irrelevant.
* tree-vect-data-refs.c (vect_verify_datarefs_alignment):
Skip irrelevant statements.
(vect_enhance_data_refs_alignment): Use STMT_VINFO_RELEVANT_P
instead of STMT_VINFO_RELEVANT.
(vect_get_data_access_cost): Do not check for supportable
alignment before calling vect_get_load_cost/vect_get_store_cost.
* tree-vect-stmts.c (vect_get_store_cost): Do not abort when
handling unsupported alignment.
(vect_get_load_cost): Likewise.
Index: gcc/tree-vect-data-refs.c
===================================================================
*** gcc/tree-vect-data-refs.c (revision 188850)
--- gcc/tree-vect-data-refs.c (working copy)
*************** vect_verify_datarefs_alignment (loop_vec
*** 1094,1099 ****
--- 1094,1102 ----
gimple stmt = DR_STMT (dr);
stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
+ if (!STMT_VINFO_RELEVANT_P (stmt_info))
+ continue;
+
/* For interleaving, only the alignment of the first access matters.
Skip statements marked as not vectorizable. */
if ((STMT_VINFO_GROUPED_ACCESS (stmt_info)
*************** vect_get_data_access_cost (struct data_r
*** 1213,1229 ****
loop_vec_info loop_vinfo = STMT_VINFO_LOOP_VINFO (stmt_info);
int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
int ncopies = vf / nunits;
- bool supportable_dr_alignment = vect_supportable_dr_alignment (dr, true);
! if (!supportable_dr_alignment)
! *inside_cost = VECT_MAX_COST;
else
! {
! if (DR_IS_READ (dr))
! vect_get_load_cost (dr, ncopies, true, inside_cost, outside_cost);
! else
! vect_get_store_cost (dr, ncopies, inside_cost);
! }
if (vect_print_dump_info (REPORT_COST))
fprintf (vect_dump, "vect_get_data_access_cost: inside_cost = %d, "
--- 1216,1226 ----
loop_vec_info loop_vinfo = STMT_VINFO_LOOP_VINFO (stmt_info);
int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
int ncopies = vf / nunits;
! if (DR_IS_READ (dr))
! vect_get_load_cost (dr, ncopies, true, inside_cost, outside_cost);
else
! vect_get_store_cost (dr, ncopies, inside_cost);
if (vect_print_dump_info (REPORT_COST))
fprintf (vect_dump, "vect_get_data_access_cost: inside_cost = %d, "
*************** vect_enhance_data_refs_alignment (loop_v
*** 1537,1543 ****
stmt = DR_STMT (dr);
stmt_info = vinfo_for_stmt (stmt);
! if (!STMT_VINFO_RELEVANT (stmt_info))
continue;
/* For interleaving, only the alignment of the first access
--- 1534,1540 ----
stmt = DR_STMT (dr);
stmt_info = vinfo_for_stmt (stmt);
! if (!STMT_VINFO_RELEVANT_P (stmt_info))
continue;
/* For interleaving, only the alignment of the first access
Index: gcc/tree-vect-stmts.c
===================================================================
*** gcc/tree-vect-stmts.c (revision 188850)
--- gcc/tree-vect-stmts.c (working copy)
*************** vect_get_store_cost (struct data_referen
*** 931,936 ****
--- 931,946 ----
break;
}
+ case dr_unaligned_unsupported:
+ {
+ *inside_cost = VECT_MAX_COST;
+
+ if (vect_print_dump_info (REPORT_COST))
+ fprintf (vect_dump, "vect_model_store_cost: unsupported access.");
+
+ break;
+ }
+
default:
gcc_unreachable ();
}
*************** vect_get_load_cost (struct data_referenc
*** 1094,1099 ****
--- 1104,1119 ----
break;
}
+ case dr_unaligned_unsupported:
+ {
+ *inside_cost = VECT_MAX_COST;
+
+ if (vect_print_dump_info (REPORT_COST))
+ fprintf (vect_dump, "vect_model_load_cost: unsupported access.");
+
+ break;
+ }
+
default:
gcc_unreachable ();
}
Index: gcc/tree-vect-slp.c
===================================================================
*** gcc/tree-vect-slp.c (revision 188850)
--- gcc/tree-vect-slp.c (working copy)
*************** vect_slp_analyze_bb_1 (basic_block bb)
*** 2050,2065 ****
return NULL;
}
- if (!vect_verify_datarefs_alignment (NULL, bb_vinfo))
- {
- if (vect_print_dump_info (REPORT_UNVECTORIZED_LOCATIONS))
- fprintf (vect_dump, "not vectorized: unsupported alignment in basic "
- "block.\n");
-
- destroy_bb_vec_info (bb_vinfo);
- return NULL;
- }
-
/* Check the SLP opportunities in the basic block, analyze and build SLP
trees. */
if (!vect_analyze_slp (NULL, bb_vinfo))
--- 2050,2055 ----
*************** vect_slp_analyze_bb_1 (basic_block bb)
*** 2082,2087 ****
--- 2072,2087 ----
vect_mark_slp_stmts_relevant (SLP_INSTANCE_TREE (instance));
}
+ if (!vect_verify_datarefs_alignment (NULL, bb_vinfo))
+ {
+ if (vect_print_dump_info (REPORT_UNVECTORIZED_LOCATIONS))
+ fprintf (vect_dump, "not vectorized: unsupported alignment in basic "
+ "block.\n");
+
+ destroy_bb_vec_info (bb_vinfo);
+ return NULL;
+ }
+
if (!vect_slp_analyze_operations (bb_vinfo))
{
if (vect_print_dump_info (REPORT_UNVECTORIZED_LOCATIONS))
--
Dr. Ulrich Weigand
GNU Toolchain for Linux on System z and Cell BE
ulrich.weig...@de.ibm.com
