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| author | Bill Schmidt <wschmidt@vnet.linux.ibm.com> | 2013-07-30 01:01:35 +0000 |
|---|---|---|
| committer | William Schmidt <wschmidt@gcc.gnu.org> | 2013-07-30 01:01:35 +0000 |
| commit | 0100cd3f7e52acbf862e6c46e5d56c348fffb88c (patch) | |
| tree | f48cb915a6aab755ebca183f4cd81b4740452ff7 /gcc/gimple-ssa-strength-reduction.c | |
| parent | ac60ce1da65d0558fb5ae39bc3f1d1f8a39adf4c (diff) | |
| download | gcc-0100cd3f7e52acbf862e6c46e5d56c348fffb88c.zip gcc-0100cd3f7e52acbf862e6c46e5d56c348fffb88c.tar.gz gcc-0100cd3f7e52acbf862e6c46e5d56c348fffb88c.tar.bz2 | |
re PR tree-optimization/57993 (ICE: verify_ssa failed (definition in block n does not dominate use in block m))
gcc:
2013-07-29 Bill Schmidt <wschmidt@vnet.linux.ibm.com>
PR tree-optimization/57993
* gimple-ssa-strength-reduction.c (replace_mult_candidate): Record
replaced statement in the candidate table.
(phi_add_costs): Return infinite cost when the hidden basis does
not dominate all phis on which the candidate is dependent.
(replace_one_candidate): Record replaced statement in the
candidate table.
gcc/testsuite:
2013-07-29 Bill Schmidt <wschmidt@vnet.linux.ibm.com>
PR tree-optimization/57993
* gcc.dg/torture/pr57993.c: New test.
From-SVN: r201325
Diffstat (limited to 'gcc/gimple-ssa-strength-reduction.c')
| -rw-r--r-- | gcc/gimple-ssa-strength-reduction.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/gcc/gimple-ssa-strength-reduction.c b/gcc/gimple-ssa-strength-reduction.c index 9a53bf7..edb1afc 100644 --- a/gcc/gimple-ssa-strength-reduction.c +++ b/gcc/gimple-ssa-strength-reduction.c @@ -1882,6 +1882,7 @@ replace_mult_candidate (slsr_cand_t c, tree basis_name, double_int bump) gimple_stmt_iterator gsi = gsi_for_stmt (c->cand_stmt); gimple_set_location (copy_stmt, gimple_location (c->cand_stmt)); gsi_replace (&gsi, copy_stmt, false); + c->cand_stmt = copy_stmt; if (dump_file && (dump_flags & TDF_DETAILS)) stmt_to_print = copy_stmt; } @@ -2179,6 +2180,18 @@ phi_add_costs (gimple phi, slsr_cand_t c, int one_add_cost) int cost = 0; slsr_cand_t phi_cand = base_cand_from_table (gimple_phi_result (phi)); + /* If we work our way back to a phi that isn't dominated by the hidden + basis, this isn't a candidate for replacement. Indicate this by + returning an unreasonably high cost. It's not easy to detect + these situations when determining the basis, so we defer the + decision until now. */ + basic_block phi_bb = gimple_bb (phi); + slsr_cand_t basis = lookup_cand (c->basis); + basic_block basis_bb = gimple_bb (basis->cand_stmt); + + if (phi_bb == basis_bb || !dominated_by_p (CDI_DOMINATORS, phi_bb, basis_bb)) + return COST_INFINITE; + for (i = 0; i < gimple_phi_num_args (phi); i++) { tree arg = gimple_phi_arg_def (phi, i); @@ -3226,6 +3239,7 @@ replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name) gimple_stmt_iterator gsi = gsi_for_stmt (c->cand_stmt); gimple_set_location (copy_stmt, gimple_location (c->cand_stmt)); gsi_replace (&gsi, copy_stmt, false); + c->cand_stmt = copy_stmt; if (dump_file && (dump_flags & TDF_DETAILS)) stmt_to_print = copy_stmt; @@ -3238,6 +3252,7 @@ replace_one_candidate (slsr_cand_t c, unsigned i, tree basis_name) NULL_TREE); gimple_set_location (cast_stmt, gimple_location (c->cand_stmt)); gsi_replace (&gsi, cast_stmt, false); + c->cand_stmt = cast_stmt; if (dump_file && (dump_flags & TDF_DETAILS)) stmt_to_print = cast_stmt; |