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| author | Jeff Law <law@redhat.com> | 2005-12-19 21:08:01 -0700 |
|---|---|---|
| committer | Jeff Law <law@gcc.gnu.org> | 2005-12-19 21:08:01 -0700 |
| commit | ea65cd378bf9c6457a2a400e2f2fef92514d06bb (patch) | |
| tree | 8d2ebf3b6d782aec9f3bf036565cf93ba43dd849 /gcc | |
| parent | 4322a86f3281d7a9d17e8316a25789c6f378321a (diff) | |
| download | gcc-ea65cd378bf9c6457a2a400e2f2fef92514d06bb.zip gcc-ea65cd378bf9c6457a2a400e2f2fef92514d06bb.tar.gz gcc-ea65cd378bf9c6457a2a400e2f2fef92514d06bb.tar.bz2 | |
tree-ssa-dom.c (thread_across_edge): Do not use local_fold.
* tree-ssa-dom.c (thread_across_edge): Do not use local_fold.
Strip away all type conversions after simplifying the
condition.
* tree-cfgcleanup.c (merge_phi_nodes): Allow merging in some
cases the forwarder block dominates the destination.
From-SVN: r108833
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 9 | ||||
| -rw-r--r-- | gcc/tree-cfgcleanup.c | 33 | ||||
| -rw-r--r-- | gcc/tree-ssa-dom.c | 11 |
3 files changed, 50 insertions, 3 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 2bd2e7c..69bfe7a 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2005-12-19 Jeff Law <law@redhat.com> + + * tree-ssa-dom.c (thread_across_edge): Do not use local_fold. + Strip away all type conversions after simplifying the + condition. + + * tree-cfgcleanup.c (merge_phi_nodes): Allow merging in some + cases the forwarder block dominates the destination. + 2005-12-19 DJ Delorie <dj@redhat.com> * reload1.c (spill_failure): Dump reload data to dump file. diff --git a/gcc/tree-cfgcleanup.c b/gcc/tree-cfgcleanup.c index 7e719c1..6f8b1c0 100644 --- a/gcc/tree-cfgcleanup.c +++ b/gcc/tree-cfgcleanup.c @@ -743,6 +743,39 @@ merge_phi_nodes (void) nodes at BB. */ *current++ = bb; } + else + { + tree phi; + + /* BB dominates DEST. There may be many users of the PHI + nodes in BB. However, there is still a trivial case we + can handle. If the result of every PHI in BB is used + only by a PHI in DEST, then we can trivially merge the + PHI nodes from BB into DEST. */ + for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) + { + tree result = PHI_RESULT (phi); + int num_uses = num_imm_uses (result); + use_operand_p imm_use; + tree use_stmt; + + /* If the PHI's result is never used, then we can just + ignore it. */ + if (num_uses == 0) + continue; + + /* Get the single use of the result of this PHI node. */ + if (!single_imm_use (result, &imm_use, &use_stmt) + || TREE_CODE (use_stmt) != PHI_NODE + || bb_for_stmt (use_stmt) != dest) + break; + } + + /* If the loop above iterated thorugh all the PHI nodes + in BB, then we can merge the PHIs from BB into DEST. */ + if (!phi) + *current++ = bb; + } } /* Now let's drain WORKLIST. */ diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c index b6257d3..45a5b7d 100644 --- a/gcc/tree-ssa-dom.c +++ b/gcc/tree-ssa-dom.c @@ -892,9 +892,14 @@ thread_across_edge (struct dom_walk_data *walk_data, edge e) TREE_OPERAND (COND_EXPR_COND (dummy_cond), 1) = op1; } - /* If the conditional folds to an invariant, then we are done, - otherwise look it up in the hash tables. */ - cached_lhs = local_fold (COND_EXPR_COND (dummy_cond)); + /* We absolutely do not care about any type conversions + we only care about a zero/nonzero value. */ + cached_lhs = fold (COND_EXPR_COND (dummy_cond)); + while (TREE_CODE (cached_lhs) == NOP_EXPR + || TREE_CODE (cached_lhs) == CONVERT_EXPR + || TREE_CODE (cached_lhs) == NON_LVALUE_EXPR) + cached_lhs = TREE_OPERAND (cached_lhs, 0); + if (! is_gimple_min_invariant (cached_lhs)) { cached_lhs = lookup_avail_expr (dummy_cond, false); |