diff options
Diffstat (limited to 'gcc/ada/gcc-interface/decl.c')
| -rw-r--r-- | gcc/ada/gcc-interface/decl.c | 71 |
1 files changed, 65 insertions, 6 deletions
diff --git a/gcc/ada/gcc-interface/decl.c b/gcc/ada/gcc-interface/decl.c index c25fb91..3575aa5 100644 --- a/gcc/ada/gcc-interface/decl.c +++ b/gcc/ada/gcc-interface/decl.c @@ -1662,7 +1662,7 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, int definition) /* If the type we are dealing with has got a smaller alignment than the natural one, we need to wrap it up in a record type and under-align the latter. We reuse the padding machinery for this purpose. */ - else if (Known_Alignment (gnat_entity) + else if (Present (Alignment_Clause (gnat_entity)) && UI_Is_In_Int_Range (Alignment (gnat_entity)) && (align = UI_To_Int (Alignment (gnat_entity)) * BITS_PER_UNIT) && align < TYPE_ALIGN (gnu_type)) @@ -4661,8 +4661,29 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, int definition) /* Back-annotate the Alignment of the type if not already in the tree. Likewise for sizes. */ if (Unknown_Alignment (gnat_entity)) - Set_Alignment (gnat_entity, - UI_From_Int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT)); + { + unsigned int double_align, align; + bool is_capped_double, align_clause; + + /* If the default alignment of "double" or larger scalar types is + specifically capped and this is not an array with an alignment + clause on the component type, return the cap. */ + if ((double_align = double_float_alignment) > 0) + is_capped_double + = is_double_float_or_array (gnat_entity, &align_clause); + else if ((double_align = double_scalar_alignment) > 0) + is_capped_double + = is_double_scalar_or_array (gnat_entity, &align_clause); + else + is_capped_double = align_clause = false; + + if (is_capped_double && !align_clause) + align = double_align; + else + align = TYPE_ALIGN (gnu_type) / BITS_PER_UNIT; + + Set_Alignment (gnat_entity, UI_From_Int (align)); + } if (Unknown_Esize (gnat_entity) && TYPE_SIZE (gnu_type)) { @@ -7507,9 +7528,47 @@ validate_alignment (Uint alignment, Entity_Id gnat_entity, unsigned int align) else if (!(Present (Alignment_Clause (gnat_entity)) && From_At_Mod (Alignment_Clause (gnat_entity))) && new_align * BITS_PER_UNIT < align) - post_error_ne_num ("alignment for& must be at least ^", - gnat_error_node, gnat_entity, - align / BITS_PER_UNIT); + { + unsigned int double_align; + bool is_capped_double, align_clause; + + /* If the default alignment of "double" or larger scalar types is + specifically capped and the new alignment is above the cap, do + not post an error and change the alignment only if there is an + alignment clause; this makes it possible to have the associated + GCC type overaligned by default for performance reasons. */ + if ((double_align = double_float_alignment) > 0) + { + Entity_Id gnat_type + = Is_Type (gnat_entity) ? gnat_entity : Etype (gnat_entity); + is_capped_double + = is_double_float_or_array (gnat_type, &align_clause); + } + else if ((double_align = double_scalar_alignment) > 0) + { + Entity_Id gnat_type + = Is_Type (gnat_entity) ? gnat_entity : Etype (gnat_entity); + is_capped_double + = is_double_scalar_or_array (gnat_type, &align_clause); + } + else + is_capped_double = align_clause = false; + + if (is_capped_double && new_align >= double_align) + { + if (align_clause) + align = new_align * BITS_PER_UNIT; + } + else + { + if (is_capped_double) + align = double_align * BITS_PER_UNIT; + + post_error_ne_num ("alignment for& must be at least ^", + gnat_error_node, gnat_entity, + align / BITS_PER_UNIT); + } + } else { new_align = (new_align > 0 ? new_align * BITS_PER_UNIT : 1); |