diff options
Diffstat (limited to 'gcc/tree-data-ref.h')
| -rw-r--r-- | gcc/tree-data-ref.h | 66 |
1 files changed, 49 insertions, 17 deletions
diff --git a/gcc/tree-data-ref.h b/gcc/tree-data-ref.h index 1559cd90bd2..a66d335f4a0 100644 --- a/gcc/tree-data-ref.h +++ b/gcc/tree-data-ref.h @@ -159,6 +159,11 @@ struct data_reference /* True when the data reference is in RHS of a stmt. */ bool is_read; + /* True when the data reference is conditional within STMT, + i.e. if it might not occur even when the statement is executed + and runs to completion. */ + bool is_conditional_in_stmt; + /* Behavior of the memory reference in the innermost loop. */ struct innermost_loop_behavior innermost; @@ -178,6 +183,7 @@ struct data_reference #define DR_NUM_DIMENSIONS(DR) DR_ACCESS_FNS (DR).length () #define DR_IS_READ(DR) (DR)->is_read #define DR_IS_WRITE(DR) (!DR_IS_READ (DR)) +#define DR_IS_CONDITIONAL_IN_STMT(DR) (DR)->is_conditional_in_stmt #define DR_BASE_ADDRESS(DR) (DR)->innermost.base_address #define DR_OFFSET(DR) (DR)->innermost.offset #define DR_INIT(DR) (DR)->innermost.init @@ -260,6 +266,9 @@ struct conflict_function struct subscript { + /* The access functions of the two references. */ + tree access_fn[2]; + /* A description of the iterations for which the elements are accessed twice. */ conflict_function *conflicting_iterations_in_a; @@ -278,6 +287,7 @@ struct subscript typedef struct subscript *subscript_p; +#define SUB_ACCESS_FN(SUB, I) (SUB)->access_fn[I] #define SUB_CONFLICTS_IN_A(SUB) (SUB)->conflicting_iterations_in_a #define SUB_CONFLICTS_IN_B(SUB) (SUB)->conflicting_iterations_in_b #define SUB_LAST_CONFLICT(SUB) (SUB)->last_conflict @@ -305,6 +315,13 @@ struct data_dependence_relation but the analyzer cannot be more specific. */ tree are_dependent; + /* If nonnull, COULD_BE_INDEPENDENT_P is true and the accesses are + independent when the runtime addresses of OBJECT_A and OBJECT_B + are different. The addresses of both objects are invariant in the + loop nest. */ + tree object_a; + tree object_b; + /* For each subscript in the dependence test, there is an element in this array. This is the attribute that labels the edge A->B of the data_dependence_relation. */ @@ -333,6 +350,33 @@ struct data_dependence_relation /* Set to true when the dependence relation is on the same data access. */ bool self_reference_p; + + /* True if the dependence described is conservatively correct rather + than exact, and if it is still possible for the accesses to be + conditionally independent. For example, the a and b references in: + + struct s *a, *b; + for (int i = 0; i < n; ++i) + a->f[i] += b->f[i]; + + conservatively have a distance vector of (0), for the case in which + a == b, but the accesses are independent if a != b. Similarly, + the a and b references in: + + struct s *a, *b; + for (int i = 0; i < n; ++i) + a[0].f[i] += b[i].f[i]; + + conservatively have a distance vector of (0), but they are indepenent + when a != b + i. In contrast, the references in: + + struct s *a; + for (int i = 0; i < n; ++i) + a->f[i] += a->f[i]; + + have the same distance vector of (0), but the accesses can never be + independent. */ + bool could_be_independent_p; }; typedef struct data_dependence_relation *ddr_p; @@ -341,6 +385,8 @@ typedef struct data_dependence_relation *ddr_p; #define DDR_B(DDR) (DDR)->b #define DDR_AFFINE_P(DDR) (DDR)->affine_p #define DDR_ARE_DEPENDENT(DDR) (DDR)->are_dependent +#define DDR_OBJECT_A(DDR) (DDR)->object_a +#define DDR_OBJECT_B(DDR) (DDR)->object_b #define DDR_SUBSCRIPTS(DDR) (DDR)->subscripts #define DDR_SUBSCRIPT(DDR, I) DDR_SUBSCRIPTS (DDR)[I] #define DDR_NUM_SUBSCRIPTS(DDR) DDR_SUBSCRIPTS (DDR).length () @@ -363,6 +409,7 @@ typedef struct data_dependence_relation *ddr_p; #define DDR_DIST_VECT(DDR, I) \ DDR_DIST_VECTS (DDR)[I] #define DDR_REVERSED_P(DDR) (DDR)->reversed_p +#define DDR_COULD_BE_INDEPENDENT_P(DDR) (DDR)->could_be_independent_p bool dr_analyze_innermost (innermost_loop_behavior *, tree, struct loop *); @@ -393,7 +440,8 @@ extern bool graphite_find_data_references_in_stmt (loop_p, loop_p, gimple *, vec<data_reference_p> *); tree find_data_references_in_loop (struct loop *, vec<data_reference_p> *); bool loop_nest_has_data_refs (loop_p loop); -struct data_reference *create_data_ref (loop_p, loop_p, tree, gimple *, bool); +struct data_reference *create_data_ref (loop_p, loop_p, tree, gimple *, bool, + bool); extern bool find_loop_nest (struct loop *, vec<loop_p> *); extern struct data_dependence_relation *initialize_data_dependence_relation (struct data_reference *, struct data_reference *, vec<loop_p>); @@ -459,22 +507,6 @@ same_data_refs (data_reference_p a, data_reference_p b) return true; } -/* Return true when the DDR contains two data references that have the - same access functions. */ - -static inline bool -same_access_functions (const struct data_dependence_relation *ddr) -{ - unsigned i; - - for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) - if (!eq_evolutions_p (DR_ACCESS_FN (DDR_A (ddr), i), - DR_ACCESS_FN (DDR_B (ddr), i))) - return false; - - return true; -} - /* Returns true when all the dependences are computable. */ inline bool |