diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 13 | ||||
| -rw-r--r-- | gcc/tree-vect-data-refs.c | 3 | ||||
| -rw-r--r-- | gcc/tree-vect-stmts.c | 12 | ||||
| -rw-r--r-- | gcc/tree-vectorizer.h | 20 |
4 files changed, 44 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index f7a764f..2000ed8 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,18 @@ 2014-01-16 Jakub Jelinek <jakub@redhat.com> + * tree-vectorizer.h (struct _loop_vec_info): Add no_data_dependencies + field. + (LOOP_VINFO_NO_DATA_DEPENDENCIES): Define. + * tree-vect-data-refs.c (vect_analyze_data_ref_dependence): Clear it + when not giving up or versioning for alias only because of + loop->safelen. + (vect_analyze_data_ref_dependences): Set to true. + * tree-vect-stmts.c (hoist_defs_of_uses): Return false if def_stmt + is a GIMPLE_PHI. + (vectorizable_load): Use LOOP_VINFO_NO_DATA_DEPENDENCIES instead of + LOOP_REQUIRES_VERSIONING_FOR_ALIAS, add && !nested_in_vect_loop + to the condition. + PR middle-end/58344 * expr.c (expand_expr_real_1): Handle init == NULL_TREE. diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c index 165e41f..0deac81 100644 --- a/gcc/tree-vect-data-refs.c +++ b/gcc/tree-vect-data-refs.c @@ -244,6 +244,7 @@ vect_analyze_data_ref_dependence (struct data_dependence_relation *ddr, { if (loop->safelen < *max_vf) *max_vf = loop->safelen; + LOOP_VINFO_NO_DATA_DEPENDENCIES (loop_vinfo) = false; return false; } @@ -291,6 +292,7 @@ vect_analyze_data_ref_dependence (struct data_dependence_relation *ddr, { if (loop->safelen < *max_vf) *max_vf = loop->safelen; + LOOP_VINFO_NO_DATA_DEPENDENCIES (loop_vinfo) = false; return false; } @@ -447,6 +449,7 @@ vect_analyze_data_ref_dependences (loop_vec_info loop_vinfo, int *max_vf) dump_printf_loc (MSG_NOTE, vect_location, "=== vect_analyze_data_ref_dependences ===\n"); + LOOP_VINFO_NO_DATA_DEPENDENCIES (loop_vinfo) = true; if (!compute_all_dependences (LOOP_VINFO_DATAREFS (loop_vinfo), &LOOP_VINFO_DDRS (loop_vinfo), LOOP_VINFO_LOOP_NEST (loop_vinfo), true)) diff --git a/gcc/tree-vect-stmts.c b/gcc/tree-vect-stmts.c index 820df7e..2a2364d 100644 --- a/gcc/tree-vect-stmts.c +++ b/gcc/tree-vect-stmts.c @@ -5504,6 +5504,8 @@ hoist_defs_of_uses (gimple stmt, struct loop *loop) dependencies within them. */ tree op2; ssa_op_iter i2; + if (gimple_code (def_stmt) == GIMPLE_PHI) + return false; FOR_EACH_SSA_TREE_OPERAND (op2, def_stmt, i2, SSA_OP_USE) { gimple def_stmt2 = SSA_NAME_DEF_STMT (op2); @@ -6434,10 +6436,12 @@ vectorizable_load (gimple stmt, gimple_stmt_iterator *gsi, gimple *vec_stmt, if (inv_p && !bb_vinfo) { gcc_assert (!grouped_load); - /* If we have versioned for aliasing then we are sure - this is a loop invariant load and thus we can insert - it on the preheader edge. */ - if (LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo) + /* If we have versioned for aliasing or the loop doesn't + have any data dependencies that would preclude this, + then we are sure this is a loop invariant load and + thus we can insert it on the preheader edge. */ + if (LOOP_VINFO_NO_DATA_DEPENDENCIES (loop_vinfo) + && !nested_in_vect_loop && hoist_defs_of_uses (stmt, loop)) { if (dump_enabled_p ()) diff --git a/gcc/tree-vectorizer.h b/gcc/tree-vectorizer.h index 935aab9..51367ea 100644 --- a/gcc/tree-vectorizer.h +++ b/gcc/tree-vectorizer.h @@ -347,6 +347,25 @@ typedef struct _loop_vec_info { fix it up. */ bool operands_swapped; + /* True if there are no loop carried data dependencies in the loop. + If loop->safelen <= 1, then this is always true, either the loop + didn't have any loop carried data dependencies, or the loop is being + vectorized guarded with some runtime alias checks, or couldn't + be vectorized at all, but then this field shouldn't be used. + For loop->safelen >= 2, the user has asserted that there are no + backward dependencies, but there still could be loop carried forward + dependencies in such loops. This flag will be false if normal + vectorizer data dependency analysis would fail or require versioning + for alias, but because of loop->safelen >= 2 it has been vectorized + even without versioning for alias. E.g. in: + #pragma omp simd + for (int i = 0; i < m; i++) + a[i] = a[i + k] * c; + (or #pragma simd or #pragma ivdep) we can vectorize this and it will + DTRT even for k > 0 && k < m, but without safelen we would not + vectorize this, so this field would be false. */ + bool no_data_dependencies; + /* If if-conversion versioned this loop before conversion, this is the loop version without if-conversion. */ struct loop *scalar_loop; @@ -385,6 +404,7 @@ typedef struct _loop_vec_info { #define LOOP_VINFO_PEELING_FOR_GAPS(L) (L)->peeling_for_gaps #define LOOP_VINFO_OPERANDS_SWAPPED(L) (L)->operands_swapped #define LOOP_VINFO_PEELING_FOR_NITER(L) (L)->peeling_for_niter +#define LOOP_VINFO_NO_DATA_DEPENDENCIES(L) (L)->no_data_dependencies #define LOOP_VINFO_SCALAR_LOOP(L) (L)->scalar_loop #define LOOP_REQUIRES_VERSIONING_FOR_ALIGNMENT(L) \ |