diff options
Diffstat (limited to 'gcc/gimple-fold.c')
| -rw-r--r-- | gcc/gimple-fold.c | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c index 2d25f9e..500e551 100644 --- a/gcc/gimple-fold.c +++ b/gcc/gimple-fold.c @@ -697,8 +697,6 @@ gimple_fold_builtin_memory_op (gimple_stmt_iterator *gsi, tree destvar, srcvar; location_t loc = gimple_location (stmt); - bool nowarn = gimple_no_warning_p (stmt); - /* If the LEN parameter is a constant zero or in range where the only valid value is zero, return DEST. */ if (size_must_be_zero_p (len)) @@ -766,12 +764,16 @@ gimple_fold_builtin_memory_op (gimple_stmt_iterator *gsi, unsigned ilen = tree_to_uhwi (len); if (pow2p_hwi (ilen)) { - /* Detect invalid bounds and overlapping copies and issue - either -Warray-bounds or -Wrestrict. */ - if (!nowarn - && check_bounds_or_overlap (as_a <gcall *>(stmt), - dest, src, len, len)) - gimple_set_no_warning (stmt, true); + /* Detect out-of-bounds accesses without issuing warnings. + Avoid folding out-of-bounds copies but to avoid false + positives for unreachable code defer warning until after + DCE has worked its magic. + -Wrestrict is still diagnosed. */ + if (int warning = check_bounds_or_overlap (as_a <gcall *>(stmt), + dest, src, len, len, + false, false)) + if (warning != OPT_Wrestrict) + return false; scalar_int_mode mode; tree type = lang_hooks.types.type_for_size (ilen * 8, 1); @@ -1038,10 +1040,16 @@ gimple_fold_builtin_memory_op (gimple_stmt_iterator *gsi, } } - /* Detect invalid bounds and overlapping copies and issue either - -Warray-bounds or -Wrestrict. */ - if (!nowarn) - check_bounds_or_overlap (as_a <gcall *>(stmt), dest, src, len, len); + /* Same as above, detect out-of-bounds accesses without issuing + warnings. Avoid folding out-of-bounds copies but to avoid + false positives for unreachable code defer warning until + after DCE has worked its magic. + -Wrestrict is still diagnosed. */ + if (int warning = check_bounds_or_overlap (as_a <gcall *>(stmt), + dest, src, len, len, + false, false)) + if (warning != OPT_Wrestrict) + return false; gimple *new_stmt; if (is_gimple_reg_type (TREE_TYPE (srcvar))) |