On Mon, Apr 30, 2012 at 6:19 PM, Ulrich Weigand <[email protected]> wrote:
> Hello,
>
> in working on a fix for PR 52633, I noticed that tree-vect-patterns.c now
> contains a number of copies of rather similar code (of which my patch
> would have added another copy), so it seems to make sense to do a bit of
> refactoring first.
>
> This patch introduced a new helper function "vect_same_loop_or_bb_p"
> to decide whether a new statement is in the same loop or basic-block
> (depending on whether we're currently doing loop-based or basic-block-based
> vectorization) as an existing statement. The helper is then used everywhere
> where this test is currently open-coded.
>
> As a side-effect, the patch actually contains two bug fixes:
>
> - The condition in some places
> (!loop && gimple_bb (def_stmt) != BB_VINFO_BB (bb_vinfo)
> && gimple_code (def_stmt) != GIMPLE_PHI)
>
> doesn't seem to make sense. It allows PHI statements from random
> other basic blocks -- but those will have an uninitialized
> vinfo_for_stmt, so if that test ever hits, we're going to crash.
>
> The check was introduced in this patch:
>
> http://gcc.gnu.org/ml/gcc-patches/2012-02/msg00191.html
>
> which likewise introduces a similar check in vect_get_and_check_slp_defs:
>
> (!loop && gimple_bb (def_stmt) == BB_VINFO_BB (bb_vinfo)
> && gimple_code (def_stmt) != GIMPLE_PHI))
>
> This makes sense: basic-block vectorization operates only on statements
> in the current basic block, but *not* on the incoming PHIs.
>
> It seems that the condition simply was incorrectly negated when moving
> it over to the tree-vect-pattern.c uses.
>
>
> - In vect_recog_widen_shift_pattern, the test for same loop / basic-block
> is still missing. In my recent patch to PR 52870 I added the check to
> vect_recog_widen_mult_pattern ... it is still missing in ...shift_pattern.
>
>
> Tested on i386-linux-gnu and arm-linux-gnueabi with no regressions.
>
> OK for mainline?
Ok.
Thanks,
Richard.
> Bye,
> Ulrich
>
>
> ChangeLog:
>
> * tree-vect-patterns.c (vect_same_loop_or_bb_p): New function.
> (vect_handle_widen_op_by_const): Use it instead of open-coding test.
> (vect_recog_widen_mult_pattern): Likewise.
> (vect_operation_fits_smaller_type): Likewise.
> (vect_recog_over_widening_pattern): Likewise.
> (vect_recog_widen_shift_pattern): Add to vect_same_loop_or_bb_p test.
>
>
> Index: gcc-head/gcc/tree-vect-patterns.c
> ===================================================================
> --- gcc-head.orig/gcc/tree-vect-patterns.c 2012-04-26 15:53:48.000000000
> +0200
> +++ gcc-head/gcc/tree-vect-patterns.c 2012-04-26 19:46:12.000000000 +0200
> @@ -84,6 +84,41 @@ new_pattern_def_seq (stmt_vec_info stmt_
> append_pattern_def_seq (stmt_info, stmt);
> }
>
> +/* Check whether STMT2 is in the same loop or basic block as STMT1.
> + Which of the two applies depends on whether we're currently doing
> + loop-based or basic-block-based vectorization, as determined by
> + the vinfo_for_stmt for STMT1 (which must be defined).
> +
> + If this returns true, vinfo_for_stmt for STMT2 is guaranteed
> + to be defined as well. */
> +
> +static bool
> +vect_same_loop_or_bb_p (gimple stmt1, gimple stmt2)
> +{
> + stmt_vec_info stmt_vinfo = vinfo_for_stmt (stmt1);
> + loop_vec_info loop_vinfo = STMT_VINFO_LOOP_VINFO (stmt_vinfo);
> + bb_vec_info bb_vinfo = STMT_VINFO_BB_VINFO (stmt_vinfo);
> +
> + if (!gimple_bb (stmt2))
> + return false;
> +
> + if (loop_vinfo)
> + {
> + struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
> + if (!flow_bb_inside_loop_p (loop, gimple_bb (stmt2)))
> + return false;
> + }
> + else
> + {
> + if (gimple_bb (stmt2) != BB_VINFO_BB (bb_vinfo)
> + || gimple_code (stmt2) == GIMPLE_PHI)
> + return false;
> + }
> +
> + gcc_assert (vinfo_for_stmt (stmt2));
> + return true;
> +}
> +
> /* Check whether NAME, an ssa-name used in USE_STMT,
> is a result of a type promotion or demotion, such that:
> DEF_STMT: NAME = NOP (name0)
> @@ -400,16 +435,6 @@ vect_handle_widen_op_by_const (gimple st
> {
> tree new_type, new_oprnd, tmp;
> gimple new_stmt;
> - loop_vec_info loop_vinfo;
> - struct loop *loop = NULL;
> - bb_vec_info bb_vinfo;
> - stmt_vec_info stmt_vinfo;
> -
> - stmt_vinfo = vinfo_for_stmt (stmt);
> - loop_vinfo = STMT_VINFO_LOOP_VINFO (stmt_vinfo);
> - bb_vinfo = STMT_VINFO_BB_VINFO (stmt_vinfo);
> - if (loop_vinfo)
> - loop = LOOP_VINFO_LOOP (loop_vinfo);
>
> if (code != MULT_EXPR && code != LSHIFT_EXPR)
> return false;
> @@ -425,12 +450,10 @@ vect_handle_widen_op_by_const (gimple st
> return true;
> }
>
> - if (TYPE_PRECISION (type) < (TYPE_PRECISION (*half_type) * 4)
> - || !gimple_bb (def_stmt)
> - || (loop && !flow_bb_inside_loop_p (loop, gimple_bb (def_stmt)))
> - || (!loop && gimple_bb (def_stmt) != BB_VINFO_BB (bb_vinfo)
> - && gimple_code (def_stmt) != GIMPLE_PHI)
> - || !vinfo_for_stmt (def_stmt))
> + if (TYPE_PRECISION (type) < (TYPE_PRECISION (*half_type) * 4))
> + return false;
> +
> + if (!vect_same_loop_or_bb_p (stmt, def_stmt))
> return false;
>
> /* TYPE is 4 times bigger than HALF_TYPE, try widening operation for
> @@ -564,16 +587,6 @@ vect_recog_widen_mult_pattern (VEC (gimp
> VEC (tree, heap) *dummy_vec;
> bool op1_ok;
> bool promotion;
> - loop_vec_info loop_vinfo;
> - struct loop *loop = NULL;
> - bb_vec_info bb_vinfo;
> - stmt_vec_info stmt_vinfo;
> -
> - stmt_vinfo = vinfo_for_stmt (last_stmt);
> - loop_vinfo = STMT_VINFO_LOOP_VINFO (stmt_vinfo);
> - bb_vinfo = STMT_VINFO_BB_VINFO (stmt_vinfo);
> - if (loop_vinfo)
> - loop = LOOP_VINFO_LOOP (loop_vinfo);
>
> if (!is_gimple_assign (last_stmt))
> return NULL;
> @@ -645,9 +658,7 @@ vect_recog_widen_mult_pattern (VEC (gimp
> || gimple_assign_rhs_code (use_stmt) != NOP_EXPR)
> return NULL;
>
> - if (!gimple_bb (use_stmt)
> - || (loop && !flow_bb_inside_loop_p (loop, gimple_bb (use_stmt)))
> - || (!loop && gimple_bb (use_stmt) != BB_VINFO_BB (bb_vinfo)))
> + if (!vect_same_loop_or_bb_p (last_stmt, use_stmt))
> return NULL;
>
> use_lhs = gimple_assign_lhs (use_stmt);
> @@ -952,14 +963,8 @@ vect_operation_fits_smaller_type (gimple
> tree interm_type = NULL_TREE, half_type, tmp, new_oprnd, type;
> gimple def_stmt, new_stmt;
> bool first = false;
> - loop_vec_info loop_info = STMT_VINFO_LOOP_VINFO (vinfo_for_stmt (stmt));
> - bb_vec_info bb_info = STMT_VINFO_BB_VINFO (vinfo_for_stmt (stmt));
> - struct loop *loop = NULL;
> bool promotion;
>
> - if (loop_info)
> - loop = LOOP_VINFO_LOOP (loop_info);
> -
> *op0 = NULL_TREE;
> *op1 = NULL_TREE;
> *new_def_stmt = NULL;
> @@ -991,13 +996,9 @@ vect_operation_fits_smaller_type (gimple
> {
> first = true;
> if (!type_conversion_p (oprnd, stmt, false, &half_type, &def_stmt,
> - &promotion)
> - || !promotion
> - || !gimple_bb (def_stmt)
> - || (loop && !flow_bb_inside_loop_p (loop, gimple_bb (def_stmt)))
> - || (!loop && gimple_bb (def_stmt) != BB_VINFO_BB (bb_info)
> - && gimple_code (def_stmt) != GIMPLE_PHI)
> - || !vinfo_for_stmt (def_stmt))
> + &promotion)
> + || !promotion
> + || !vect_same_loop_or_bb_p (stmt, def_stmt))
> return false;
> }
>
> @@ -1171,16 +1172,6 @@ vect_recog_over_widening_pattern (VEC (g
> tree var = NULL_TREE, new_type = NULL_TREE, tmp, new_oprnd;
> bool first;
> tree type = NULL;
> - loop_vec_info loop_vinfo;
> - struct loop *loop = NULL;
> - bb_vec_info bb_vinfo;
> - stmt_vec_info stmt_vinfo;
> -
> - stmt_vinfo = vinfo_for_stmt (stmt);
> - loop_vinfo = STMT_VINFO_LOOP_VINFO (stmt_vinfo);
> - bb_vinfo = STMT_VINFO_BB_VINFO (stmt_vinfo);
> - if (loop_vinfo)
> - loop = LOOP_VINFO_LOOP (loop_vinfo);
>
> first = true;
> while (1)
> @@ -1212,9 +1203,7 @@ vect_recog_over_widening_pattern (VEC (g
> }
>
> if (nuses != 1 || !is_gimple_assign (use_stmt)
> - || !gimple_bb (use_stmt)
> - || (loop && !flow_bb_inside_loop_p (loop, gimple_bb (use_stmt)))
> - || (!loop && gimple_bb (use_stmt) != BB_VINFO_BB (bb_vinfo)))
> + || !vect_same_loop_or_bb_p (stmt, use_stmt))
> return NULL;
>
> /* Create pattern statement for STMT. */
> @@ -1495,6 +1484,9 @@ vect_recog_widen_shift_pattern (VEC (gim
> || !CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (use_stmt)))
> return NULL;
>
> + if (!vect_same_loop_or_bb_p (last_stmt, use_stmt))
> + return NULL;
> +
> use_lhs = gimple_assign_lhs (use_stmt);
> use_type = TREE_TYPE (use_lhs);
>
> --
> Dr. Ulrich Weigand
> GNU Toolchain for Linux on System z and Cell BE
> [email protected]
>
