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| author | Richard Biener <rguenther@suse.de> | 2015-07-16 07:19:24 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2015-07-16 07:19:24 +0000 |
| commit | 612b9d1364bbefb708245c6cd5b5bfa2718926e6 (patch) | |
| tree | 9c87181ff8efc2ef85a2ee497faa4320ecf25ed8 /gcc | |
| parent | 4c3b378b5a9ddba3a66fa24203df5e850b4de3d6 (diff) | |
| download | gcc-612b9d1364bbefb708245c6cd5b5bfa2718926e6.zip gcc-612b9d1364bbefb708245c6cd5b5bfa2718926e6.tar.gz gcc-612b9d1364bbefb708245c6cd5b5bfa2718926e6.tar.bz2 | |
tree-ssa-dom.c (dom_valueize): New function.
2015-07-16 Richard Biener <rguenther@suse.de>
* tree-ssa-dom.c (dom_valueize): New function.
(record_temporary_equivalences): Also record equivalences
for dominating stmts that have uses of equivalences we are
about to record.
From-SVN: r225860
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/tree-ssa-dom.c | 50 |
2 files changed, 56 insertions, 1 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 8e38205..47c7c16 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2015-07-16 Richard Biener <rguenther@suse.de> + + * tree-ssa-dom.c (dom_valueize): New function. + (record_temporary_equivalences): Also record equivalences + for dominating stmts that have uses of equivalences we are + about to record. + 2015-07-16 Bin Cheng <bin.cheng@arm.com> * tree-ssa-loop-ivopts.c (add_candidate): Remove call to diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c index 77f4ac0..3eb003c 100644 --- a/gcc/tree-ssa-dom.c +++ b/gcc/tree-ssa-dom.c @@ -1401,6 +1401,20 @@ simplify_stmt_for_jump_threading (gimple stmt, return lookup_avail_expr (stmt, false); } +/* Valueize hook for gimple_fold_stmt_to_constant_1. */ + +static tree +dom_valueize (tree t) +{ + if (TREE_CODE (t) == SSA_NAME) + { + tree tem = SSA_NAME_VALUE (t); + if (tem) + return tem; + } + return t; +} + /* Record into the equivalence tables any equivalences implied by traversing edge E (which are cached in E->aux). @@ -1428,7 +1442,6 @@ record_temporary_equivalences (edge e) additional equivalences. */ if (lhs && TREE_CODE (lhs) == SSA_NAME - && is_gimple_constant (rhs) && TREE_CODE (rhs) == INTEGER_CST) { gimple defstmt = SSA_NAME_DEF_STMT (lhs); @@ -1456,6 +1469,41 @@ record_temporary_equivalences (edge e) } } + /* If LHS is an SSA_NAME with a new equivalency then try if + stmts with uses of that LHS that dominate the edge destination + simplify and allow further equivalences to be recorded. */ + if (lhs && TREE_CODE (lhs) == SSA_NAME) + { + use_operand_p use_p; + imm_use_iterator iter; + FOR_EACH_IMM_USE_FAST (use_p, iter, lhs) + { + gimple use_stmt = USE_STMT (use_p); + + /* Only bother to record more equivalences for lhs that + can be directly used by e->dest. + ??? If the code gets re-organized to a worklist to + catch more indirect opportunities and it is made to + handle PHIs then this should only consider use_stmts + in basic-blocks we have already visited. */ + if (e->dest == gimple_bb (use_stmt) + || !dominated_by_p (CDI_DOMINATORS, + e->dest, gimple_bb (use_stmt))) + continue; + tree lhs2 = gimple_get_lhs (use_stmt); + if (lhs2 && TREE_CODE (lhs2) == SSA_NAME) + { + tree res + = gimple_fold_stmt_to_constant_1 (use_stmt, dom_valueize, + no_follow_ssa_edges); + if (res + && (TREE_CODE (res) == SSA_NAME + || is_gimple_min_invariant (res))) + record_equality (lhs2, res); + } + } + } + /* If we have 0 = COND or 1 = COND equivalences, record them into our expression hash tables. */ for (i = 0; edge_info->cond_equivalences.iterate (i, &eq); ++i) |