diff options
Diffstat (limited to 'gcc/tree-cfg.c')
| -rw-r--r-- | gcc/tree-cfg.c | 40 |
1 files changed, 23 insertions, 17 deletions
diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c index 944b31f..70d0404 100644 --- a/gcc/tree-cfg.c +++ b/gcc/tree-cfg.c @@ -1060,18 +1060,23 @@ group_case_labels (void) tree labels = SWITCH_LABELS (stmt); int old_size = TREE_VEC_LENGTH (labels); int i, j, new_size = old_size; - tree default_case = TREE_VEC_ELT (labels, old_size - 1); - tree default_label; + tree default_case = NULL_TREE; + tree default_label = NULL_TREE; /* The default label is always the last case in a switch - statement after gimplification. */ - default_label = CASE_LABEL (default_case); + statement after gimplification if it was not optimized + away. */ + if (!CASE_LOW (TREE_VEC_ELT (labels, old_size - 1)) + && !CASE_HIGH (TREE_VEC_ELT (labels, old_size - 1))) + { + default_case = TREE_VEC_ELT (labels, old_size - 1); + default_label = CASE_LABEL (default_case); + old_size--; + } - /* Look for possible opportunities to merge cases. - Ignore the last element of the label vector because it - must be the default case. */ + /* Look for possible opportunities to merge cases. */ i = 0; - while (i < old_size - 1) + while (i < old_size) { tree base_case, base_label, base_high; base_case = TREE_VEC_ELT (labels, i); @@ -1095,7 +1100,7 @@ group_case_labels (void) /* Try to merge case labels. Break out when we reach the end of the label vector or when we cannot merge the next case label with the current one. */ - while (i < old_size - 1) + while (i < old_size) { tree merge_case = TREE_VEC_ELT (labels, i); tree merge_label = CASE_LABEL (merge_case); @@ -4604,13 +4609,16 @@ tree_verify_flow_info (void) /* Verify that the case labels are sorted. */ prev = TREE_VEC_ELT (vec, 0); - for (i = 1; i < n - 1; ++i) + for (i = 1; i < n; ++i) { tree c = TREE_VEC_ELT (vec, i); if (! CASE_LOW (c)) { - error ("found default case not at end of case vector"); - err = 1; + if (i != n - 1) + { + error ("found default case not at end of case vector"); + err = 1; + } continue; } if (! tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c))) @@ -4624,11 +4632,9 @@ tree_verify_flow_info (void) } prev = c; } - if (CASE_LOW (TREE_VEC_ELT (vec, n - 1))) - { - error ("no default case found at end of case vector"); - err = 1; - } + /* VRP will remove the default case if it can prove it will + never be executed. So do not verify there always exists + a default case here. */ FOR_EACH_EDGE (e, ei, bb->succs) { |