diff options
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 | |
parent | 770fe3a36400fb03d0936cff86ffb76a136d5674 (diff) | |
download | gcc-e8bf3d5ed983791a658b86f4eae338e13b6fdc3f.zip gcc-e8bf3d5ed983791a658b86f4eae338e13b6fdc3f.tar.gz gcc-e8bf3d5ed983791a658b86f4eae338e13b6fdc3f.tar.bz2 |
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
-rw-r--r-- | gcc/ChangeLog | 5 | ||||
-rw-r--r-- | gcc/builtins.c | 11 | ||||
-rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
-rw-r--r-- | gcc/testsuite/gcc.dg/pr86572.c | 11 |
4 files changed, 28 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a7f3afd..ac121a8 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,10 @@ 2018-11-04 Bernd Edlinger <bernd.edlinger@hotmail.de> + PR tree-optimization/86572 + * builtins.c (c_strlen): Handle negative offsets in a safe way. + +2018-11-04 Bernd Edlinger <bernd.edlinger@hotmail.de> + PR tree-optimization/87672 * gimple-fold.c (gimple_fold_builtin_stxcpy_chk): Gimplify. * tree-ssa-strlen.c (handle_builtin_strcat): Adjust object size. 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)); } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 79a7859..a28d9a0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,10 @@ 2018-11-04 Bernd Edlinger <bernd.edlinger@hotmail.de> + PR tree-optimization/86572 + * gcc.dg/pr86572.c: New test. + +2018-11-04 Bernd Edlinger <bernd.edlinger@hotmail.de> + PR tree-optimization/87672 * gcc.dg/pr87672.c: New test. diff --git a/gcc/testsuite/gcc.dg/pr86572.c b/gcc/testsuite/gcc.dg/pr86572.c new file mode 100644 index 0000000..6cda55b --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr86572.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ + +const char buf[40] = "test"; +void test (int x) +{ + if (__builtin_strlen (buf + x) > 4) + __builtin_abort (); +} + +/* { dg-final { scan-tree-dump-not "abort" "optimized" } } */ |