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| author | Bernd Edlinger <bernd.edlinger@hotmail.de> | 2018-11-04 19:51:09 +0000 |
|---|---|---|
| committer | Bernd Edlinger <edlinger@gcc.gnu.org> | 2018-11-04 19:51:09 +0000 |
| commit | e8bf3d5ed983791a658b86f4eae338e13b6fdc3f (patch) | |
| tree | cbca26e118c1d2a7c2ab243b2d4405fbd561b565 /gcc/builtins.c | |
| parent | 770fe3a36400fb03d0936cff86ffb76a136d5674 (diff) | |
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re PR tree-optimization/86572 (unsafe strlen folding of const arguments with non-const offset)
gcc:
2018-11-04 Bernd Edlinger <bernd.edlinger@hotmail.de>
PR tree-optimization/86572
* builtins.c (c_strlen): Handle negative offsets in a safe way.
testsuite:
2018-11-04 Bernd Edlinger <bernd.edlinger@hotmail.de>
PR tree-optimization/86572
* gcc.dg/pr86572.c: New test.
From-SVN: r265778
Diffstat (limited to 'gcc/builtins.c')
| -rw-r--r-- | gcc/builtins.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/gcc/builtins.c b/gcc/builtins.c index f64b3d4..9f2a90a 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -734,11 +734,14 @@ c_strlen (tree src, int only_value, c_strlen_data *data, unsigned eltsize) of the string subtract the offset from the length of the string, and return that. Otherwise the length is zero. Take care to use SAVE_EXPR in case the OFFSET has side-effects. */ - tree offsave = TREE_SIDE_EFFECTS (byteoff) ? save_expr (byteoff) : byteoff; - offsave = fold_convert (ssizetype, offsave); + tree offsave = TREE_SIDE_EFFECTS (byteoff) ? save_expr (byteoff) + : byteoff; + offsave = fold_convert_loc (loc, sizetype, offsave); tree condexp = fold_build2_loc (loc, LE_EXPR, boolean_type_node, offsave, - build_int_cst (ssizetype, len)); - tree lenexp = size_diffop_loc (loc, ssize_int (len), offsave); + size_int (len)); + tree lenexp = fold_build2_loc (loc, MINUS_EXPR, sizetype, size_int (len), + offsave); + lenexp = fold_convert_loc (loc, ssizetype, lenexp); return fold_build3_loc (loc, COND_EXPR, ssizetype, condexp, lenexp, build_zero_cst (ssizetype)); } |