diff options
Diffstat (limited to 'gcc/tree-ssa-loop-manip.cc')
| -rw-r--r-- | gcc/tree-ssa-loop-manip.cc | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/gcc/tree-ssa-loop-manip.cc b/gcc/tree-ssa-loop-manip.cc index 598e218..f336d22 100644 --- a/gcc/tree-ssa-loop-manip.cc +++ b/gcc/tree-ssa-loop-manip.cc @@ -47,7 +47,9 @@ along with GCC; see the file COPYING3. If not see so that we can free them all at once. */ static bitmap_obstack loop_renamer_obstack; -/* Creates an induction variable with value BASE + STEP * iteration in LOOP. +/* Creates an induction variable with value BASE (+/-) STEP * iteration in LOOP. + If INCR_OP is PLUS_EXPR, the induction variable is BASE + STEP * iteration. + If INCR_OP is MINUS_EXPR, the induction variable is BASE - STEP * iteration. It is expected that neither BASE nor STEP are shared with other expressions (unless the sharing rules allow this). Use VAR as a base var_decl for it (if NULL, a new temporary will be created). The increment will occur at @@ -57,16 +59,16 @@ static bitmap_obstack loop_renamer_obstack; VAR_AFTER (unless they are NULL). */ void -create_iv (tree base, tree step, tree var, class loop *loop, - gimple_stmt_iterator *incr_pos, bool after, - tree *var_before, tree *var_after) +create_iv (tree base, tree_code incr_op, tree step, tree var, class loop *loop, + gimple_stmt_iterator *incr_pos, bool after, tree *var_before, + tree *var_after) { gassign *stmt; gphi *phi; tree initial, step1; gimple_seq stmts; tree vb, va; - enum tree_code incr_op = PLUS_EXPR; + gcc_assert (incr_op == PLUS_EXPR || incr_op == MINUS_EXPR); edge pe = loop_preheader_edge (loop); if (var != NULL_TREE) @@ -93,7 +95,7 @@ create_iv (tree base, tree step, tree var, class loop *loop, step1 = fold_build1 (NEGATE_EXPR, TREE_TYPE (step), step); if (tree_int_cst_lt (step1, step)) { - incr_op = MINUS_EXPR; + incr_op = (incr_op == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR); step = step1; } } @@ -104,7 +106,7 @@ create_iv (tree base, tree step, tree var, class loop *loop, if (!tree_expr_nonnegative_warnv_p (step, &ovf) && may_negate_without_overflow_p (step)) { - incr_op = MINUS_EXPR; + incr_op = (incr_op == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR); step = fold_build1 (NEGATE_EXPR, TREE_TYPE (step), step); } } @@ -1365,7 +1367,7 @@ tree_transform_and_unroll_loop (class loop *loop, unsigned factor, tree ctr_before, ctr_after; gimple_stmt_iterator bsi = gsi_last_nondebug_bb (new_exit->src); exit_if = as_a <gcond *> (gsi_stmt (bsi)); - create_iv (exit_base, exit_step, NULL_TREE, loop, + create_iv (exit_base, PLUS_EXPR, exit_step, NULL_TREE, loop, &bsi, false, &ctr_before, &ctr_after); gimple_cond_set_code (exit_if, exit_cmp); gimple_cond_set_lhs (exit_if, ctr_after); @@ -1580,8 +1582,8 @@ canonicalize_loop_ivs (class loop *loop, tree *nit, bool bump_in_latch) gsi = gsi_last_bb (loop->latch); else gsi = gsi_last_nondebug_bb (loop->header); - create_iv (build_int_cst_type (type, 0), build_int_cst (type, 1), NULL_TREE, - loop, &gsi, bump_in_latch, &var_before, NULL); + create_iv (build_int_cst_type (type, 0), PLUS_EXPR, build_int_cst (type, 1), + NULL_TREE, loop, &gsi, bump_in_latch, &var_before, NULL); rewrite_all_phi_nodes_with_iv (loop, var_before); |