diff options
Diffstat (limited to 'gcc/tree.h')
| -rw-r--r-- | gcc/tree.h | 30 |
1 files changed, 20 insertions, 10 deletions
@@ -105,7 +105,7 @@ extern const enum tree_code_class tree_code_type[]; #define MTAG_P(CODE) \ (TREE_CODE (CODE) == STRUCT_FIELD_TAG \ || TREE_CODE (CODE) == NAME_MEMORY_TAG \ - || TREE_CODE (CODE) == TYPE_MEMORY_TAG) + || TREE_CODE (CODE) == SYMBOL_MEMORY_TAG) /* Nonzero if DECL represents a VAR_DECL or FUNCTION_DECL. */ @@ -2298,12 +2298,21 @@ struct tree_decl_minimal GTY(()) /* When computing aliasing information, we represent the memory pointed-to by pointers with artificial variables called "memory tags" (MT). There - are two kinds of tags: type and name. Type tags (TMT) are used in - type-based alias analysis, they represent all the pointed-to locations - and variables of the same alias set class. Name tags (NMT) are used in - flow-sensitive points-to alias analysis, they represent the variables - and memory locations pointed-to by a specific SSA_NAME pointer. */ - + are two kinds of tags, namely symbol and name: + + Symbol tags (SMT) are used in flow-insensitive alias analysis, they + represent all the pointed-to locations and variables pointed-to by + the same pointer symbol. Usually, this set is computed using + type-based analysis (i.e., alias set classes), but this may not + always be the case. + + Name tags (NMT) are used in flow-sensitive points-to alias + analysis, they represent the variables and memory locations + pointed-to by a specific SSA_NAME pointer. + + In general, given a pointer P with a symbol tag SMT, the alias set + of SMT should be the union of all the alias sets of the NMTs of + every SSA_NAME for P. */ struct tree_memory_tag GTY(()) { struct tree_decl_minimal common; @@ -2313,9 +2322,10 @@ struct tree_memory_tag GTY(()) #define MTAG_GLOBAL(NODE) (TREE_MEMORY_TAG_CHECK (NODE)->mtag.is_global) -/* This flag is true if a TMT is used as the vdef or vuse operand directly, - because the access had all of the TMT's aliases pruned from it. */ -#define TMT_USED_ALONE(NODE) (TYPE_MEMORY_TAG_CHECK (NODE)->mtag.is_used_alone) +/* This flag is true if a SMT is used as the V_MAY_DEF or VUSE operand + directly, because the access had all of the SMT's aliases pruned + from it. */ +#define SMT_USED_ALONE(NODE) (SYMBOL_MEMORY_TAG_CHECK (NODE)->mtag.is_used_alone) struct tree_struct_field_tag GTY(()) { |