The following tries to correct get_origin_and_offset_r not handling non-constant sizes of array elements in ARRAY_REFs and non-constant offsets of COMPONENT_REFs. It isn't exactly clear how such failures should be treated in this API and existing handling isn't consistent here either. The following applies two different variants, treating non-constant array sizes like non-constant array indices and treating non-constant offsets of COMPONENT_REFs by terminating the recursion (not sure what that means to the callers).
Basically the code failed to use component_ref_field_offset and array_ref_element_size and instead relies on inappropriate helpers (that shouldn't exist in the first place ...). The code is also not safe-guarded against overflows in the final offset/size computations but I'm not trying to rectify that. Martin - can you comment on how the API should handle such situations? Bootstrapped and tested on x86_64-unknown-linux-gnu. OK for trunk and branches? Thanks, Richard. 2022-05-16 Richard Biener <rguent...@suse.de> PR middle-end/105604 * gimple-ssa-sprintf.cc (get_origin_and_offset_r): Handle non-constant ARRAY_REF element size and non-constant COMPONENT_REF field offset. * gcc.dg/torture/pr105604.c: New testcase. --- gcc/gimple-ssa-sprintf.cc | 14 +++++++++++--- gcc/testsuite/gcc.dg/torture/pr105604.c | 24 ++++++++++++++++++++++++ 2 files changed, 35 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/torture/pr105604.c diff --git a/gcc/gimple-ssa-sprintf.cc b/gcc/gimple-ssa-sprintf.cc index c93f12f90b5..14e215ce69c 100644 --- a/gcc/gimple-ssa-sprintf.cc +++ b/gcc/gimple-ssa-sprintf.cc @@ -2312,14 +2312,16 @@ get_origin_and_offset_r (tree x, HOST_WIDE_INT *fldoff, HOST_WIDE_INT *fldsize, HOST_WIDE_INT idx = (tree_fits_uhwi_p (offset) ? tree_to_uhwi (offset) : HOST_WIDE_INT_MAX); + tree elsz = array_ref_element_size (x); tree eltype = TREE_TYPE (x); if (TREE_CODE (eltype) == INTEGER_TYPE) { if (off) *off = idx; } - else if (idx < HOST_WIDE_INT_MAX) - *fldoff += idx * int_size_in_bytes (eltype); + else if (idx < HOST_WIDE_INT_MAX + && tree_fits_shwi_p (elsz)) + *fldoff += idx * tree_to_shwi (elsz); else *fldoff = idx; @@ -2350,8 +2352,14 @@ get_origin_and_offset_r (tree x, HOST_WIDE_INT *fldoff, HOST_WIDE_INT *fldsize, case COMPONENT_REF: { + tree foff = component_ref_field_offset (x); tree fld = TREE_OPERAND (x, 1); - *fldoff += int_byte_position (fld); + if (!tree_fits_shwi_p (foff) + || !tree_fits_shwi_p (DECL_FIELD_BIT_OFFSET (fld))) + return x; + *fldoff += (tree_to_shwi (foff) + + (tree_to_shwi (DECL_FIELD_BIT_OFFSET (fld)) + / BITS_PER_UNIT)); get_origin_and_offset_r (fld, fldoff, fldsize, off); x = TREE_OPERAND (x, 0); diff --git a/gcc/testsuite/gcc.dg/torture/pr105604.c b/gcc/testsuite/gcc.dg/torture/pr105604.c new file mode 100644 index 00000000000..b002251df10 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr105604.c @@ -0,0 +1,24 @@ +/* { dg-do compile } */ +/* { dg-additional-options "-Wall" } */ + +struct { + long users; + long size; + char *data; +} * main_trans; +void *main___trans_tmp_1; +int sprintf(char *, char *, ...); +int main() { + int users = 0; + struct { + long users; + long size; + char *data; + int links[users]; + char buf[]; + } *trans = trans; + trans->data = trans->buf; + main___trans_tmp_1 = trans; + main_trans = main___trans_tmp_1; + sprintf(main_trans->data, "test"); +} -- 2.35.3