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| author | Martin Liska <mliska@suse.cz> | 2017-06-21 14:51:46 +0200 |
|---|---|---|
| committer | Martin Liska <marxin@gcc.gnu.org> | 2017-06-21 12:51:46 +0000 |
| commit | e59a1c22fb249388e82b4fd004f33615abe36d2e (patch) | |
| tree | 0ba9b3f978dc6746d354dccdfb340b58bb47cbfb /gcc/gimplify.c | |
| parent | ff9baa5f1c532a43d7d14a800f5a4a5c5757dca6 (diff) | |
| download | gcc-e59a1c22fb249388e82b4fd004f33615abe36d2e.zip gcc-e59a1c22fb249388e82b4fd004f33615abe36d2e.tar.gz gcc-e59a1c22fb249388e82b4fd004f33615abe36d2e.tar.bz2 | |
Make early return predictor more precise.
2017-06-21 Martin Liska <mliska@suse.cz>
PR tree-optimization/79489
* gimplify.c (maybe_add_early_return_predict_stmt): New
function.
(gimplify_return_expr): Call the function.
* predict.c (tree_estimate_probability_bb): Remove handling
of early return.
* predict.def: Update comment about early return predictor.
* gimple-predict.h (is_gimple_predict): New function.
* predict.def: Change default value of early return to 66.
* tree-tailcall.c (find_tail_calls): Skip GIMPLE_PREDICT
statements.
* passes.def: Put pass_strip_predict_hints to the beginning of
IPA passes.
From-SVN: r249450
Diffstat (limited to 'gcc/gimplify.c')
| -rw-r--r-- | gcc/gimplify.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/gcc/gimplify.c b/gcc/gimplify.c index 13760c0..c645bce 100644 --- a/gcc/gimplify.c +++ b/gcc/gimplify.c @@ -1428,6 +1428,20 @@ gimplify_bind_expr (tree *expr_p, gimple_seq *pre_p) return GS_ALL_DONE; } +/* Maybe add early return predict statement to PRE_P sequence. */ + +static void +maybe_add_early_return_predict_stmt (gimple_seq *pre_p) +{ + /* If we are not in a conditional context, add PREDICT statement. */ + if (gimple_conditional_context ()) + { + gimple *predict = gimple_build_predict (PRED_TREE_EARLY_RETURN, + NOT_TAKEN); + gimplify_seq_add_stmt (pre_p, predict); + } +} + /* Gimplify a RETURN_EXPR. If the expression to be returned is not a GIMPLE value, it is assigned to a new temporary and the statement is re-written to return the temporary. @@ -1458,6 +1472,7 @@ gimplify_return_expr (tree stmt, gimple_seq *pre_p) || TREE_CODE (ret_expr) == RESULT_DECL || ret_expr == error_mark_node) { + maybe_add_early_return_predict_stmt (pre_p); greturn *ret = gimple_build_return (ret_expr); gimple_set_no_warning (ret, TREE_NO_WARNING (stmt)); gimplify_seq_add_stmt (pre_p, ret); @@ -1525,6 +1540,7 @@ gimplify_return_expr (tree stmt, gimple_seq *pre_p) gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p); + maybe_add_early_return_predict_stmt (pre_p); ret = gimple_build_return (result); gimple_set_no_warning (ret, TREE_NO_WARNING (stmt)); gimplify_seq_add_stmt (pre_p, ret); |