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| author | Jakub Jelinek <jakub@redhat.com> | 2018-09-12 20:28:20 +0200 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2018-09-12 20:28:20 +0200 |
| commit | c0cbe5260fab673f7cd755df2226422b88b28837 (patch) | |
| tree | 80f2a40dc45418305b5aabf0aed406735df224de /gcc/cfgexpand.c | |
| parent | 8e36332cf65b4ec5a1ea6b4b3a6ae8cb6ed9f455 (diff) | |
re PR middle-end/82853 (Optimize x % 3 == 0 without modulo)
PR middle-end/82853
* expr.h (maybe_optimize_mod_cmp): Declare.
* expr.c (mod_inv): New function.
(maybe_optimize_mod_cmp): New function.
(do_store_flag): Use it.
* cfgexpand.c (expand_gimple_cond): Likewise.
* gcc.target/i386/pr82853-1.c: New test.
* gcc.target/i386/pr82853-2.c: New test.
From-SVN: r264248
Diffstat (limited to 'gcc/cfgexpand.c')
| -rw-r--r-- | gcc/cfgexpand.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c index 2d3111da25d..697b238669f 100644 --- a/gcc/cfgexpand.c +++ b/gcc/cfgexpand.c @@ -2477,6 +2477,13 @@ expand_gimple_cond (basic_block bb, gcond *stmt) } } + /* Optimize (x % C1) == C2 or (x % C1) != C2 if it is beneficial + into (x - C2) * C3 < C4. */ + if ((code == EQ_EXPR || code == NE_EXPR) + && TREE_CODE (op0) == SSA_NAME + && TREE_CODE (op1) == INTEGER_CST) + code = maybe_optimize_mod_cmp (code, &op0, &op1); + last2 = last = get_last_insn (); extract_true_false_edges_from_block (bb, &true_edge, &false_edge); |