diff options
Diffstat (limited to 'gcc/tree.h')
| -rw-r--r-- | gcc/tree.h | 29 |
1 files changed, 29 insertions, 0 deletions
@@ -848,6 +848,33 @@ struct tree_exp the debugging output format in use. */ #define BLOCK_NUMBER(NODE) (BLOCK_CHECK (NODE)->block.block_num) +/* If block reordering splits a lexical block into discontiguous + address ranges, we'll make a copy of the original block. + + Note that this is logically distinct from BLOCK_ABSTRACT_ORIGIN. + In that case, we have one source block that has been replicated + (through inlining or unrolling) into many logical blocks, and that + these logical blocks have different physical variables in them. + + In this case, we have one logical block split into several + non-contiguous address ranges. Most debug formats can't actually + represent this idea directly, so we fake it by creating multiple + logical blocks with the same variables in them. However, for those + that do support non-contiguous regions, these allow the original + logical block to be reconstructed, along with the set of address + ranges. + + One of the logical block fragments is arbitrarily chosen to be + the ORIGIN. The other fragments will point to the origin via + BLOCK_FRAGMENT_ORIGIN; the origin itself will have this pointer + be null. The list of fragments will be chained through + BLOCK_FRAGMENT_CHAIN from the origin. */ + +#define BLOCK_FRAGMENT_ORIGIN(NODE) \ + (BLOCK_CHECK (NODE)->block.fragment_origin) +#define BLOCK_FRAGMENT_CHAIN(NODE) \ + (BLOCK_CHECK (NODE)->block.fragment_chain) + struct tree_block { struct tree_common common; @@ -860,6 +887,8 @@ struct tree_block union tree_node *subblocks; union tree_node *supercontext; union tree_node *abstract_origin; + union tree_node *fragment_origin; + union tree_node *fragment_chain; }; /* Define fields and accessors for nodes representing data types. */ |