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authorrakdver <rakdver@138bc75d-0d04-0410-961f-82ee72b054a4>2004-08-24 20:48:23 +0000
committerrakdver <rakdver@138bc75d-0d04-0410-961f-82ee72b054a4>2004-08-24 20:48:23 +0000
commitbb445479def5c8fcb62ba57aa917feec3228322c (patch)
tree437eb45f8de15cfc88b0b52b021ad483bab2b80e /gcc/tree-ssa-loop-manip.c
parent00b5c4a1dc915e2696b48e960b1d67272c83079a (diff)
downloadgcc-bb445479def5c8fcb62ba57aa917feec3228322c.tar.gz
* tree-ssa-loop-ivcanon.c: New file.
* tree-ssa-loop-manip.c (create_iv): New function. * Makefile.in (tree-ssa-loop-ivcanon.o): Add. (tree-ssa-loop.o, tree-ssa-loop-manip.o): Add SCEV_H dependency. * cfgloop.c (mark_single_exit_loops): New function. (verify_loop_structure): Verify single-exit loops. * cfgloop.h (struct loop): Add single_exit field. (LOOPS_HAVE_MARKED_SINGLE_EXITS): New constant. (mark_single_exit_loops): Declare. (tree_num_loop_insns): Declare. * cfgloopmanip.c (update_single_exits_after_duplication): New function. (duplicate_loop_to_header_edge): Use it. * common.opt (fivcanon): New flag. * timevar.def (TV_TREE_LOOP_IVCANON, TV_COMPLETE_UNROLL): New timevars. * tree-cfg.c (tree_find_edge_insert_loc): Return newly created block. (bsi_commit_edge_inserts_1): Pass null to tree_find_edge_insert_loc. (bsi_insert_on_edge_immediate): New function. * tree-flow.h (bsi_insert_on_edge_immediate, canonicalize_induction_variables, tree_unroll_loops_completely, create_iv): Declare. * tree-optimize.c (init_tree_optimization_passes): Add pass_iv_canon and pass_complete_unroll. * tree-pass.h (pass_iv_canon, pass_complete_unroll): Declare. * tree-scalar-evolution.c (get_loop_exit_condition, get_exit_conditions_rec, number_of_iterations_in_loop, scev_initialize): Use single_exit information. * tree-ssa-loop-niter.c (number_of_iterations_cond): Record missing assumptions. (loop_niter_by_eval): Return number of iterations as unsigned int. * tree-ssa-loop.c (tree_ssa_loop_init): Mark single exit loops. (tree_ssa_loop_ivcanon, gate_tree_ssa_loop_ivcanon, pass_iv_canon, tree_complete_unroll, gate_tree_complete_unroll, pass_complete_unroll): New passes. (tree_ssa_loop_done): Call free_numbers_of_iterations_estimates. * tree-ssanames.c (make_ssa_name): Allow creating ssa name before the defining statement is ready. * tree-vectorizer.c (vect_create_iv_simple): Removed. (vect_create_index_for_array_ref, vect_transform_loop_bound): Use create_iv. (vect_transform_loop_bound): Use single_exit information. (vect_analyze_loop_form): Cleanup bogus tests. (vectorize_loops): Do not call flow_loop_scan. * tree.h (may_negate_without_overflow_p): Declare. * fold-const.c (may_negate_without_overflow_p): Split out from ... (negate_expr_p): ... this function. (tree_expr_nonzero_p): Handle overflowed constants correctly. * doc/invoke.texi (-fivcanon): Document. * doc/passes.texi: Document canonical induction variable creation. * gcc.dg/tree-ssa/loop-1.c: New test. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@86516 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/tree-ssa-loop-manip.c')
-rw-r--r--gcc/tree-ssa-loop-manip.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/gcc/tree-ssa-loop-manip.c b/gcc/tree-ssa-loop-manip.c
index 19b0ca25589..e096d265f21 100644
--- a/gcc/tree-ssa-loop-manip.c
+++ b/gcc/tree-ssa-loop-manip.c
@@ -37,6 +37,77 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
#include "cfglayout.h"
#include "tree-scalar-evolution.h"
+/* Creates an induction variable with value BASE + STEP * iteration in LOOP.
+ 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
+ INCR_POS (after it if AFTER is true, before it otherwise). The ssa versions
+ of the variable before and after increment will be stored in VAR_BEFORE and
+ VAR_AFTER (unless they are NULL). */
+
+void
+create_iv (tree base, tree step, tree var, struct loop *loop,
+ block_stmt_iterator *incr_pos, bool after,
+ tree *var_before, tree *var_after)
+{
+ tree stmt, initial, step1;
+ tree vb, va;
+ enum tree_code incr_op = PLUS_EXPR;
+
+ if (!var)
+ {
+ var = create_tmp_var (TREE_TYPE (base), "ivtmp");
+ add_referenced_tmp_var (var);
+ }
+
+ vb = make_ssa_name (var, NULL_TREE);
+ if (var_before)
+ *var_before = vb;
+ va = make_ssa_name (var, NULL_TREE);
+ if (var_after)
+ *var_after = va;
+
+ /* For easier readability of the created code, produce MINUS_EXPRs
+ when suitable. */
+ if (TREE_CODE (step) == INTEGER_CST)
+ {
+ if (TYPE_UNSIGNED (TREE_TYPE (step)))
+ {
+ step1 = fold (build1 (NEGATE_EXPR, TREE_TYPE (step), step));
+ if (tree_int_cst_lt (step1, step))
+ {
+ incr_op = MINUS_EXPR;
+ step = step1;
+ }
+ }
+ else
+ {
+ if (!tree_expr_nonnegative_p (step)
+ && may_negate_without_overflow_p (step))
+ {
+ incr_op = MINUS_EXPR;
+ step = fold (build1 (NEGATE_EXPR, TREE_TYPE (step), step));
+ }
+ }
+ }
+
+ stmt = build2 (MODIFY_EXPR, void_type_node, va,
+ build2 (incr_op, TREE_TYPE (base),
+ vb, step));
+ SSA_NAME_DEF_STMT (va) = stmt;
+ if (after)
+ bsi_insert_after (incr_pos, stmt, BSI_NEW_STMT);
+ else
+ bsi_insert_before (incr_pos, stmt, BSI_NEW_STMT);
+
+ initial = base;
+
+ stmt = create_phi_node (vb, loop->header);
+ SSA_NAME_DEF_STMT (vb) = stmt;
+ add_phi_arg (&stmt, initial, loop_preheader_edge (loop));
+ add_phi_arg (&stmt, va, loop_latch_edge (loop));
+}
+
/* Add exit phis for the USE on EXIT. */
static void