diff options
Diffstat (limited to 'gcc/gimple-fold.c')
| -rw-r--r-- | gcc/gimple-fold.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c index bf00a0f0460..d1c5c89546f 100644 --- a/gcc/gimple-fold.c +++ b/gcc/gimple-fold.c @@ -3231,7 +3231,7 @@ fold_nonarray_ctor_reference (tree type, tree ctor, double_int bitoffset; double_int byte_offset_cst = tree_to_double_int (byte_offset); double_int bits_per_unit_cst = uhwi_to_double_int (BITS_PER_UNIT); - double_int bitoffset_end; + double_int bitoffset_end, access_end; /* Variable sized objects in static constructors makes no sense, but field_size can be NULL for flexible array members. */ @@ -3252,14 +3252,16 @@ fold_nonarray_ctor_reference (tree type, tree ctor, else bitoffset_end = double_int_zero; - /* Is OFFSET in the range (BITOFFSET, BITOFFSET_END)? */ - if (double_int_cmp (uhwi_to_double_int (offset), bitoffset, 0) >= 0 + access_end = double_int_add (uhwi_to_double_int (offset), + uhwi_to_double_int (size)); + + /* Is there any overlap between [OFFSET, OFFSET+SIZE) and + [BITOFFSET, BITOFFSET_END)? */ + if (double_int_cmp (access_end, bitoffset, 0) > 0 && (field_size == NULL_TREE || double_int_cmp (uhwi_to_double_int (offset), bitoffset_end, 0) < 0)) { - double_int access_end = double_int_add (uhwi_to_double_int (offset), - uhwi_to_double_int (size)); double_int inner_offset = double_int_sub (uhwi_to_double_int (offset), bitoffset); /* We do have overlap. Now see if field is large enough to @@ -3267,6 +3269,8 @@ fold_nonarray_ctor_reference (tree type, tree ctor, fields. */ if (double_int_cmp (access_end, bitoffset_end, 0) > 0) return NULL_TREE; + if (double_int_cmp (uhwi_to_double_int (offset), bitoffset, 0) < 0) + return NULL_TREE; return fold_ctor_reference (type, cval, double_int_to_uhwi (inner_offset), size); } |