X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Ftree-ssa-operands.c;h=0e931ca74a9d7449941243ca14acc84ed2f626ee;hb=b7d1b569577509f4a733da7949c899c936db453b;hp=0e0f3650ddcab4db94dad47640d301a6f9768096;hpb=3fefae7a51f38acf585785f19e5dac4bd01b7172;p=pf3gnuchains%2Fgcc-fork.git diff --git a/gcc/tree-ssa-operands.c b/gcc/tree-ssa-operands.c index 0e0f3650ddc..0e931ca74a9 100644 --- a/gcc/tree-ssa-operands.c +++ b/gcc/tree-ssa-operands.c @@ -1,5 +1,5 @@ /* SSA operands management for trees. - Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc. + Copyright (C) 2003, 2004, 2005, 2006 Free Software Foundation, Inc. This file is part of GCC. @@ -74,10 +74,7 @@ Boston, MA 02110-1301, USA. */ i.e., if a stmt had a VUSE of 'a_5', and 'a' occurs in the new operand vector for VUSE, then the new vector will also be modified such that - it contains 'a_5' rather than 'a'. - -*/ - + it contains 'a_5' rather than 'a'. */ /* Flags to describe operand properties in helpers. */ @@ -85,7 +82,7 @@ Boston, MA 02110-1301, USA. */ #define opf_none 0 /* Operand is the target of an assignment expression or a - call-clobbered variable */ + call-clobbered variable. */ #define opf_is_def (1 << 0) /* Operand is the target of an assignment expression. */ @@ -99,62 +96,53 @@ Boston, MA 02110-1301, USA. */ VUSE for 'b'. */ #define opf_no_vops (1 << 2) -/* Operand is a "non-specific" kill for call-clobbers and such. This is used - to distinguish "reset the world" events from explicit MODIFY_EXPRs. */ +/* Operand is a "non-specific" kill for call-clobbers and such. This + is used to distinguish "reset the world" events from explicit + MODIFY_EXPRs. */ #define opf_non_specific (1 << 3) - /* Array for building all the def operands. */ static VEC(tree,heap) *build_defs; /* Array for building all the use operands. */ static VEC(tree,heap) *build_uses; -/* Array for building all the v_may_def operands. */ +/* Array for building all the V_MAY_DEF operands. */ static VEC(tree,heap) *build_v_may_defs; -/* Array for building all the vuse operands. */ +/* Array for building all the VUSE operands. */ static VEC(tree,heap) *build_vuses; -/* Array for building all the v_must_def operands. */ +/* Array for building all the V_MUST_DEF operands. */ static VEC(tree,heap) *build_v_must_defs; -/* True if the operands for call clobbered vars are cached and valid. */ -bool ssa_call_clobbered_cache_valid; -bool ssa_ro_call_cache_valid; - /* These arrays are the cached operand vectors for call clobbered calls. */ -static VEC(tree,heap) *clobbered_v_may_defs; -static VEC(tree,heap) *clobbered_vuses; -static VEC(tree,heap) *ro_call_vuses; -static bool clobbered_aliased_loads; -static bool clobbered_aliased_stores; -static bool ro_call_aliased_loads; static bool ops_active = false; static GTY (()) struct ssa_operand_memory_d *operand_memory = NULL; static unsigned operand_memory_index; static void get_expr_operands (tree, tree *, int); -static void get_asm_expr_operands (tree); -static void get_indirect_ref_operands (tree, tree, int); -static void get_tmr_operands (tree, tree, int); -static void get_call_expr_operands (tree, tree); -static inline void append_def (tree *); -static inline void append_use (tree *); -static void append_v_may_def (tree); -static void append_v_must_def (tree); -static void add_call_clobber_ops (tree, tree); -static void add_call_read_ops (tree); -static void add_stmt_operand (tree *, stmt_ann_t, int); -static void build_ssa_operands (tree stmt); - + static def_optype_p free_defs = NULL; static use_optype_p free_uses = NULL; static vuse_optype_p free_vuses = NULL; static maydef_optype_p free_maydefs = NULL; static mustdef_optype_p free_mustdefs = NULL; +/* Allocates operand OP of given TYPE from the appropriate free list, + or of the new value if the list is empty. */ + +#define ALLOC_OPTYPE(OP, TYPE) \ + do \ + { \ + TYPE##_optype_p ret = free_##TYPE##s; \ + if (ret) \ + free_##TYPE##s = ret->next; \ + else \ + ret = ssa_operand_alloc (sizeof (*ret)); \ + (OP) = ret; \ + } while (0) /* Return the DECL_UID of the base variable of T. */ @@ -167,6 +155,7 @@ get_name_decl (tree t) return DECL_UID (SSA_NAME_VAR (t)); } + /* Comparison function for qsort used in operand_build_sort_virtual. */ static int @@ -186,14 +175,17 @@ operand_build_cmp (const void *p, const void *q) return (u1 > u2 ? 1 : -1); } + /* Sort the virtual operands in LIST from lowest DECL_UID to highest. */ static inline void operand_build_sort_virtual (VEC(tree,heap) *list) { int num = VEC_length (tree, list); + if (num < 2) return; + if (num == 2) { if (get_name_decl (VEC_index (tree, list, 0)) @@ -206,6 +198,7 @@ operand_build_sort_virtual (VEC(tree,heap) *list) } return; } + /* There are 3 or more elements, call qsort. */ qsort (VEC_address (tree, list), VEC_length (tree, list), @@ -214,8 +207,7 @@ operand_build_sort_virtual (VEC(tree,heap) *list) } - -/* Return true if the ssa operands cache is active. */ +/* Return true if the SSA operands cache is active. */ bool ssa_operands_active (void) @@ -224,6 +216,35 @@ ssa_operands_active (void) } +/* Structure storing statistics on how many call clobbers we have, and + how many where avoided. */ + +static struct +{ + /* Number of call-clobbered ops we attempt to add to calls in + add_call_clobber_ops. */ + unsigned int clobbered_vars; + + /* Number of write-clobbers (V_MAY_DEFs) avoided by using + not_written information. */ + unsigned int static_write_clobbers_avoided; + + /* Number of reads (VUSEs) avoided by using not_read information. */ + unsigned int static_read_clobbers_avoided; + + /* Number of write-clobbers avoided because the variable can't escape to + this call. */ + unsigned int unescapable_clobbers_avoided; + + /* Number of read-only uses we attempt to add to calls in + add_call_read_ops. */ + unsigned int readonly_clobbers; + + /* Number of read-only uses we avoid using not_read information. */ + unsigned int static_readonly_clobbers_avoided; +} clobber_stats; + + /* Initialize the operand cache routines. */ void @@ -238,6 +259,7 @@ init_ssa_operands (void) gcc_assert (operand_memory == NULL); operand_memory_index = SSA_OPERAND_MEMORY_SIZE; ops_active = true; + memset (&clobber_stats, 0, sizeof (clobber_stats)); } @@ -263,10 +285,23 @@ fini_ssa_operands (void) ggc_free (ptr); } - VEC_free (tree, heap, clobbered_v_may_defs); - VEC_free (tree, heap, clobbered_vuses); - VEC_free (tree, heap, ro_call_vuses); ops_active = false; + + if (dump_file && (dump_flags & TDF_STATS)) + { + fprintf (dump_file, "Original clobbered vars:%d\n", + clobber_stats.clobbered_vars); + fprintf (dump_file, "Static write clobbers avoided:%d\n", + clobber_stats.static_write_clobbers_avoided); + fprintf (dump_file, "Static read clobbers avoided:%d\n", + clobber_stats.static_read_clobbers_avoided); + fprintf (dump_file, "Unescapable clobbers avoided:%d\n", + clobber_stats.unescapable_clobbers_avoided); + fprintf (dump_file, "Original read-only clobbers:%d\n", + clobber_stats.readonly_clobbers); + fprintf (dump_file, "Static read-only clobbers avoided:%d\n", + clobber_stats.static_readonly_clobbers_avoided); + } } @@ -279,7 +314,7 @@ ssa_operand_alloc (unsigned size) if (operand_memory_index + size >= SSA_OPERAND_MEMORY_SIZE) { struct ssa_operand_memory_d *ptr; - ptr = ggc_alloc (sizeof (struct ssa_operand_memory_d)); + ptr = GGC_NEW (struct ssa_operand_memory_d); ptr->next = operand_memory; operand_memory = ptr; operand_memory_index = 0; @@ -290,78 +325,202 @@ ssa_operand_alloc (unsigned size) } -/* Make sure PTR is in the correct immediate use list. Since uses are simply - pointers into the stmt TREE, there is no way of telling if anyone has - changed what this pointer points to via TREE_OPERANDS (exp, 0) = <...>. - The contents are different, but the pointer is still the same. This - routine will check to make sure PTR is in the correct list, and if it isn't - put it in the correct list. We cannot simply check the previous node - because all nodes in the same stmt might have be changed. */ + +/* This routine makes sure that PTR is in an immediate use list, and makes + sure the stmt pointer is set to the current stmt. */ static inline void -correct_use_link (use_operand_p ptr, tree stmt) +set_virtual_use_link (use_operand_p ptr, tree stmt) { - use_operand_p prev; - tree root; - - /* Fold_stmt () may have changed the stmt pointers. */ + /* fold_stmt may have changed the stmt pointers. */ if (ptr->stmt != stmt) ptr->stmt = stmt; - prev = ptr->prev; - if (prev) - { - /* Find the root element, making sure we skip any safe iterators. */ - while (prev->use != NULL || prev->stmt == NULL) - prev = prev->prev; - - /* Get the ssa_name of the list the node is in. */ - root = prev->stmt; - /* If it's the right list, simply return. */ - if (root == *(ptr->use)) - return; - } - /* Its in the wrong list if we reach here. */ - delink_imm_use (ptr); - link_imm_use (ptr, *(ptr->use)); + /* If this use isn't in a list, add it to the correct list. */ + if (!ptr->prev) + link_imm_use (ptr, *(ptr->use)); } +/* Appends ELT after TO, and moves the TO pointer to ELT. */ + +#define APPEND_OP_AFTER(ELT, TO) \ + do \ + { \ + (TO)->next = (ELT); \ + (TO) = (ELT); \ + } while (0) + +/* Appends head of list FROM after TO, and move both pointers + to their successors. */ + +#define MOVE_HEAD_AFTER(FROM, TO) \ + do \ + { \ + APPEND_OP_AFTER (FROM, TO); \ + (FROM) = (FROM)->next; \ + } while (0) + +/* Moves OP to appropriate freelist. OP is set to its successor. */ + +#define MOVE_HEAD_TO_FREELIST(OP, TYPE) \ + do \ + { \ + TYPE##_optype_p next = (OP)->next; \ + (OP)->next = free_##TYPE##s; \ + free_##TYPE##s = (OP); \ + (OP) = next; \ + } while (0) + +/* Initializes immediate use at USE_PTR to value VAL, and links it to the list + of immediate uses. STMT is the current statement. */ + +#define INITIALIZE_USE(USE_PTR, VAL, STMT) \ + do \ + { \ + (USE_PTR)->use = (VAL); \ + link_imm_use_stmt ((USE_PTR), *(VAL), (STMT)); \ + } while (0) + +/* Adds OP to the list of defs after LAST, and moves + LAST to the new element. */ -/* This routine makes sure that PTR is in an immediate use list, and makes - sure the stmt pointer is set to the current stmt. Virtual uses do not need - the overhead of correct_use_link since they cannot be directly manipulated - like a real use can be. (They don't exist in the TREE_OPERAND nodes.) */ static inline void -set_virtual_use_link (use_operand_p ptr, tree stmt) +add_def_op (tree *op, def_optype_p *last) { - /* Fold_stmt () may have changed the stmt pointers. */ - if (ptr->stmt != stmt) - ptr->stmt = stmt; + def_optype_p new; - /* If this use isn't in a list, add it to the correct list. */ - if (!ptr->prev) - link_imm_use (ptr, *(ptr->use)); + ALLOC_OPTYPE (new, def); + DEF_OP_PTR (new) = op; + APPEND_OP_AFTER (new, *last); +} + +/* Adds OP to the list of uses of statement STMT after LAST, and moves + LAST to the new element. */ + +static inline void +add_use_op (tree stmt, tree *op, use_optype_p *last) +{ + use_optype_p new; + + ALLOC_OPTYPE (new, use); + INITIALIZE_USE (USE_OP_PTR (new), op, stmt); + APPEND_OP_AFTER (new, *last); +} + +/* Adds OP to the list of vuses of statement STMT after LAST, and moves + LAST to the new element. */ + +static inline void +add_vuse_op (tree stmt, tree op, vuse_optype_p *last) +{ + vuse_optype_p new; + + ALLOC_OPTYPE (new, vuse); + VUSE_OP (new) = op; + INITIALIZE_USE (VUSE_OP_PTR (new), &VUSE_OP (new), stmt); + APPEND_OP_AFTER (new, *last); +} + +/* Adds OP to the list of maydefs of statement STMT after LAST, and moves + LAST to the new element. */ + +static inline void +add_maydef_op (tree stmt, tree op, maydef_optype_p *last) +{ + maydef_optype_p new; + + ALLOC_OPTYPE (new, maydef); + MAYDEF_RESULT (new) = op; + MAYDEF_OP (new) = op; + INITIALIZE_USE (MAYDEF_OP_PTR (new), &MAYDEF_OP (new), stmt); + APPEND_OP_AFTER (new, *last); +} + +/* Adds OP to the list of mustdefs of statement STMT after LAST, and moves + LAST to the new element. */ + +static inline void +add_mustdef_op (tree stmt, tree op, mustdef_optype_p *last) +{ + mustdef_optype_p new; + + ALLOC_OPTYPE (new, mustdef); + MUSTDEF_RESULT (new) = op; + MUSTDEF_KILL (new) = op; + INITIALIZE_USE (MUSTDEF_KILL_PTR (new), &MUSTDEF_KILL (new), stmt); + APPEND_OP_AFTER (new, *last); } +/* Takes elements from build_defs and turns them into def operands of STMT. + TODO -- Given that def operands list is not necessarily sorted, merging + the operands this way does not make much sense. + -- Make build_defs VEC of tree *. */ + +static inline void +finalize_ssa_def_ops (tree stmt) +{ + unsigned new_i; + struct def_optype_d new_list; + def_optype_p old_ops, last; + tree *old_base; + + new_list.next = NULL; + last = &new_list; + + old_ops = DEF_OPS (stmt); + + new_i = 0; + while (old_ops && new_i < VEC_length (tree, build_defs)) + { + tree *new_base = (tree *) VEC_index (tree, build_defs, new_i); + old_base = DEF_OP_PTR (old_ops); + + if (old_base == new_base) + { + /* if variables are the same, reuse this node. */ + MOVE_HEAD_AFTER (old_ops, last); + new_i++; + } + else if (old_base < new_base) + { + /* if old is less than new, old goes to the free list. */ + MOVE_HEAD_TO_FREELIST (old_ops, def); + } + else + { + /* This is a new operand. */ + add_def_op (new_base, &last); + new_i++; + } + } + + /* If there is anything remaining in the build_defs list, simply emit it. */ + for ( ; new_i < VEC_length (tree, build_defs); new_i++) + add_def_op ((tree *) VEC_index (tree, build_defs, new_i), &last); + + last->next = NULL; + + /* If there is anything in the old list, free it. */ + if (old_ops) + { + old_ops->next = free_defs; + free_defs = old_ops; + } + /* Now set the stmt's operands. */ + DEF_OPS (stmt) = new_list.next; -#define FINALIZE_OPBUILD build_defs -#define FINALIZE_OPBUILD_BASE(I) (tree *)VEC_index (tree, \ - build_defs, (I)) -#define FINALIZE_OPBUILD_ELEM(I) (tree *)VEC_index (tree, \ - build_defs, (I)) -#define FINALIZE_FUNC finalize_ssa_def_ops -#define FINALIZE_ALLOC alloc_def -#define FINALIZE_FREE free_defs -#define FINALIZE_TYPE struct def_optype_d -#define FINALIZE_ELEM(PTR) ((PTR)->def_ptr) -#define FINALIZE_OPS DEF_OPS -#define FINALIZE_BASE(VAR) VAR -#define FINALIZE_BASE_TYPE tree * -#define FINALIZE_BASE_ZERO NULL -#define FINALIZE_INITIALIZE(PTR, VAL, STMT) FINALIZE_ELEM (PTR) = (VAL) -#include "tree-ssa-opfinalize.h" +#ifdef ENABLE_CHECKING + { + def_optype_p ptr; + unsigned x = 0; + for (ptr = DEF_OPS (stmt); ptr; ptr = ptr->next) + x++; + gcc_assert (x == VEC_length (tree, build_defs)); + } +#endif +} /* This routine will create stmt operands for STMT from the def build list. */ @@ -369,37 +528,59 @@ static void finalize_ssa_defs (tree stmt) { unsigned int num = VEC_length (tree, build_defs); + /* There should only be a single real definition per assignment. */ gcc_assert ((stmt && TREE_CODE (stmt) != MODIFY_EXPR) || num <= 1); /* If there is an old list, often the new list is identical, or close, so find the elements at the beginning that are the same as the vector. */ - finalize_ssa_def_ops (stmt); VEC_truncate (tree, build_defs, 0); } -#define FINALIZE_OPBUILD build_uses -#define FINALIZE_OPBUILD_BASE(I) (tree *)VEC_index (tree, \ - build_uses, (I)) -#define FINALIZE_OPBUILD_ELEM(I) (tree *)VEC_index (tree, \ - build_uses, (I)) -#define FINALIZE_FUNC finalize_ssa_use_ops -#define FINALIZE_ALLOC alloc_use -#define FINALIZE_FREE free_uses -#define FINALIZE_TYPE struct use_optype_d -#define FINALIZE_ELEM(PTR) ((PTR)->use_ptr.use) -#define FINALIZE_OPS USE_OPS -#define FINALIZE_USE_PTR(PTR) USE_OP_PTR (PTR) -#define FINALIZE_CORRECT_USE correct_use_link -#define FINALIZE_BASE(VAR) VAR -#define FINALIZE_BASE_TYPE tree * -#define FINALIZE_BASE_ZERO NULL -#define FINALIZE_INITIALIZE(PTR, VAL, STMT) \ - (PTR)->use_ptr.use = (VAL); \ - link_imm_use_stmt (&((PTR)->use_ptr), \ - *(VAL), (STMT)) -#include "tree-ssa-opfinalize.h" +/* Takes elements from build_uses and turns them into use operands of STMT. + TODO -- Make build_uses VEC of tree *. */ + +static inline void +finalize_ssa_use_ops (tree stmt) +{ + unsigned new_i; + struct use_optype_d new_list; + use_optype_p old_ops, ptr, last; + + new_list.next = NULL; + last = &new_list; + + old_ops = USE_OPS (stmt); + + /* If there is anything in the old list, free it. */ + if (old_ops) + { + for (ptr = old_ops; ptr; ptr = ptr->next) + delink_imm_use (USE_OP_PTR (ptr)); + old_ops->next = free_uses; + free_uses = old_ops; + } + + /* Now create nodes for all the new nodes. */ + for (new_i = 0; new_i < VEC_length (tree, build_uses); new_i++) + add_use_op (stmt, (tree *) VEC_index (tree, build_uses, new_i), &last); + + last->next = NULL; + + /* Now set the stmt's operands. */ + USE_OPS (stmt) = new_list.next; + +#ifdef ENABLE_CHECKING + { + unsigned x = 0; + for (ptr = USE_OPS (stmt); ptr; ptr = ptr->next) + x++; + + gcc_assert (x == VEC_length (tree, build_uses)); + } +#endif +} /* Return a new use operand vector for STMT, comparing to OLD_OPS_P. */ @@ -413,7 +594,7 @@ finalize_ssa_uses (tree stmt) /* If the pointer to the operand is the statement itself, something is wrong. It means that we are pointing to a local variable (the - initial call to get_stmt_operands does not pass a pointer to a + initial call to update_stmt_operands does not pass a pointer to a statement). */ for (x = 0; x < num; x++) gcc_assert (*((tree *)VEC_index (tree, build_uses, x)) != stmt); @@ -422,33 +603,82 @@ finalize_ssa_uses (tree stmt) finalize_ssa_use_ops (stmt); VEC_truncate (tree, build_uses, 0); } - - -/* Return a new v_may_def operand vector for STMT, comparing to OLD_OPS_P. */ -#define FINALIZE_OPBUILD build_v_may_defs -#define FINALIZE_OPBUILD_ELEM(I) VEC_index (tree, build_v_may_defs, (I)) -#define FINALIZE_OPBUILD_BASE(I) get_name_decl (VEC_index (tree, \ - build_v_may_defs, (I))) -#define FINALIZE_FUNC finalize_ssa_v_may_def_ops -#define FINALIZE_ALLOC alloc_maydef -#define FINALIZE_FREE free_maydefs -#define FINALIZE_TYPE struct maydef_optype_d -#define FINALIZE_ELEM(PTR) MAYDEF_RESULT (PTR) -#define FINALIZE_OPS MAYDEF_OPS -#define FINALIZE_USE_PTR(PTR) MAYDEF_OP_PTR (PTR) -#define FINALIZE_CORRECT_USE set_virtual_use_link -#define FINALIZE_BASE_ZERO 0 -#define FINALIZE_BASE(VAR) get_name_decl (VAR) -#define FINALIZE_BASE_TYPE unsigned -#define FINALIZE_INITIALIZE(PTR, VAL, STMT) \ - (PTR)->def_var = (VAL); \ - (PTR)->use_var = (VAL); \ - (PTR)->use_ptr.use = &((PTR)->use_var); \ - link_imm_use_stmt (&((PTR)->use_ptr), \ - (VAL), (STMT)) -#include "tree-ssa-opfinalize.h" - - + + +/* Takes elements from build_v_may_defs and turns them into maydef operands of + STMT. */ + +static inline void +finalize_ssa_v_may_def_ops (tree stmt) +{ + unsigned new_i; + struct maydef_optype_d new_list; + maydef_optype_p old_ops, ptr, last; + tree act; + unsigned old_base, new_base; + + new_list.next = NULL; + last = &new_list; + + old_ops = MAYDEF_OPS (stmt); + + new_i = 0; + while (old_ops && new_i < VEC_length (tree, build_v_may_defs)) + { + act = VEC_index (tree, build_v_may_defs, new_i); + new_base = get_name_decl (act); + old_base = get_name_decl (MAYDEF_OP (old_ops)); + + if (old_base == new_base) + { + /* if variables are the same, reuse this node. */ + MOVE_HEAD_AFTER (old_ops, last); + set_virtual_use_link (MAYDEF_OP_PTR (last), stmt); + new_i++; + } + else if (old_base < new_base) + { + /* if old is less than new, old goes to the free list. */ + delink_imm_use (MAYDEF_OP_PTR (old_ops)); + MOVE_HEAD_TO_FREELIST (old_ops, maydef); + } + else + { + /* This is a new operand. */ + add_maydef_op (stmt, act, &last); + new_i++; + } + } + + /* If there is anything remaining in the build_v_may_defs list, simply emit it. */ + for ( ; new_i < VEC_length (tree, build_v_may_defs); new_i++) + add_maydef_op (stmt, VEC_index (tree, build_v_may_defs, new_i), &last); + + last->next = NULL; + + /* If there is anything in the old list, free it. */ + if (old_ops) + { + for (ptr = old_ops; ptr; ptr = ptr->next) + delink_imm_use (MAYDEF_OP_PTR (ptr)); + old_ops->next = free_maydefs; + free_maydefs = old_ops; + } + + /* Now set the stmt's operands. */ + MAYDEF_OPS (stmt) = new_list.next; + +#ifdef ENABLE_CHECKING + { + unsigned x = 0; + for (ptr = MAYDEF_OPS (stmt); ptr; ptr = ptr->next) + x++; + + gcc_assert (x == VEC_length (tree, build_v_may_defs)); + } +#endif +} + static void finalize_ssa_v_may_defs (tree stmt) { @@ -456,7 +686,7 @@ finalize_ssa_v_may_defs (tree stmt) } -/* Clear the in_list bits and empty the build array for v_may_defs. */ +/* Clear the in_list bits and empty the build array for V_MAY_DEFs. */ static inline void cleanup_v_may_defs (void) @@ -476,31 +706,82 @@ cleanup_v_may_defs (void) VEC_truncate (tree, build_v_may_defs, 0); } + +/* Takes elements from build_vuses and turns them into vuse operands of + STMT. */ + +static inline void +finalize_ssa_vuse_ops (tree stmt) +{ + unsigned new_i; + struct vuse_optype_d new_list; + vuse_optype_p old_ops, ptr, last; + tree act; + unsigned old_base, new_base; + + new_list.next = NULL; + last = &new_list; + + old_ops = VUSE_OPS (stmt); + + new_i = 0; + while (old_ops && new_i < VEC_length (tree, build_vuses)) + { + act = VEC_index (tree, build_vuses, new_i); + new_base = get_name_decl (act); + old_base = get_name_decl (VUSE_OP (old_ops)); + + if (old_base == new_base) + { + /* if variables are the same, reuse this node. */ + MOVE_HEAD_AFTER (old_ops, last); + set_virtual_use_link (VUSE_OP_PTR (last), stmt); + new_i++; + } + else if (old_base < new_base) + { + /* if old is less than new, old goes to the free list. */ + delink_imm_use (USE_OP_PTR (old_ops)); + MOVE_HEAD_TO_FREELIST (old_ops, vuse); + } + else + { + /* This is a new operand. */ + add_vuse_op (stmt, act, &last); + new_i++; + } + } + + /* If there is anything remaining in the build_vuses list, simply emit it. */ + for ( ; new_i < VEC_length (tree, build_vuses); new_i++) + add_vuse_op (stmt, VEC_index (tree, build_vuses, new_i), &last); + + last->next = NULL; + + /* If there is anything in the old list, free it. */ + if (old_ops) + { + for (ptr = old_ops; ptr; ptr = ptr->next) + delink_imm_use (VUSE_OP_PTR (ptr)); + old_ops->next = free_vuses; + free_vuses = old_ops; + } + + /* Now set the stmt's operands. */ + VUSE_OPS (stmt) = new_list.next; + +#ifdef ENABLE_CHECKING + { + unsigned x = 0; + for (ptr = VUSE_OPS (stmt); ptr; ptr = ptr->next) + x++; + + gcc_assert (x == VEC_length (tree, build_vuses)); + } +#endif +} -#define FINALIZE_OPBUILD build_vuses -#define FINALIZE_OPBUILD_ELEM(I) VEC_index (tree, build_vuses, (I)) -#define FINALIZE_OPBUILD_BASE(I) get_name_decl (VEC_index (tree, \ - build_vuses, (I))) -#define FINALIZE_FUNC finalize_ssa_vuse_ops -#define FINALIZE_ALLOC alloc_vuse -#define FINALIZE_FREE free_vuses -#define FINALIZE_TYPE struct vuse_optype_d -#define FINALIZE_ELEM(PTR) VUSE_OP (PTR) -#define FINALIZE_OPS VUSE_OPS -#define FINALIZE_USE_PTR(PTR) VUSE_OP_PTR (PTR) -#define FINALIZE_CORRECT_USE set_virtual_use_link -#define FINALIZE_BASE_ZERO 0 -#define FINALIZE_BASE(VAR) get_name_decl (VAR) -#define FINALIZE_BASE_TYPE unsigned -#define FINALIZE_INITIALIZE(PTR, VAL, STMT) \ - (PTR)->use_var = (VAL); \ - (PTR)->use_ptr.use = &((PTR)->use_var); \ - link_imm_use_stmt (&((PTR)->use_ptr), \ - (VAL), (STMT)) -#include "tree-ssa-opfinalize.h" - - -/* Return a new vuse operand vector, comparing to OLD_OPS_P. */ +/* Return a new VUSE operand vector, comparing to OLD_OPS_P. */ static void finalize_ssa_vuses (tree stmt) @@ -509,17 +790,16 @@ finalize_ssa_vuses (tree stmt) unsigned vuse_index; /* Remove superfluous VUSE operands. If the statement already has a - V_MAY_DEF operation for a variable 'a', then a VUSE for 'a' is not - needed because V_MAY_DEFs imply a VUSE of the variable. For instance, - suppose that variable 'a' is aliased: + V_MAY_DEF operation for a variable 'a', then a VUSE for 'a' is + not needed because V_MAY_DEFs imply a VUSE of the variable. For + instance, suppose that variable 'a' is aliased: # VUSE # a_3 = V_MAY_DEF a = a + 1; - The VUSE is superfluous because it is implied by the V_MAY_DEF - operation. */ - + The VUSE is superfluous because it is implied by the + V_MAY_DEF operation. */ num = VEC_length (tree, build_vuses); num_v_may_defs = VEC_length (tree, build_v_may_defs); @@ -543,63 +823,114 @@ finalize_ssa_vuses (tree stmt) } } else - /* Clear out the in_list bits. */ - for (vuse_index = 0; - vuse_index < VEC_length (tree, build_vuses); - vuse_index++) - { - tree t = VEC_index (tree, build_vuses, vuse_index); - if (TREE_CODE (t) != SSA_NAME) - { - var_ann_t ann = var_ann (t); - ann->in_vuse_list = 0; - } - } + { + /* Clear out the in_list bits. */ + for (vuse_index = 0; + vuse_index < VEC_length (tree, build_vuses); + vuse_index++) + { + tree t = VEC_index (tree, build_vuses, vuse_index); + if (TREE_CODE (t) != SSA_NAME) + { + var_ann_t ann = var_ann (t); + ann->in_vuse_list = 0; + } + } + } finalize_ssa_vuse_ops (stmt); - /* The v_may_def build vector wasn't cleaned up because we needed it. */ + + /* The V_MAY_DEF build vector wasn't cleaned up because we needed it. */ cleanup_v_may_defs (); - /* Free the vuses build vector. */ + /* Free the VUSEs build vector. */ VEC_truncate (tree, build_vuses, 0); } - -/* Return a new v_must_def operand vector for STMT, comparing to OLD_OPS_P. */ - -#define FINALIZE_OPBUILD build_v_must_defs -#define FINALIZE_OPBUILD_ELEM(I) VEC_index (tree, build_v_must_defs, (I)) -#define FINALIZE_OPBUILD_BASE(I) get_name_decl (VEC_index (tree, \ - build_v_must_defs, (I))) -#define FINALIZE_FUNC finalize_ssa_v_must_def_ops -#define FINALIZE_ALLOC alloc_mustdef -#define FINALIZE_FREE free_mustdefs -#define FINALIZE_TYPE struct mustdef_optype_d -#define FINALIZE_ELEM(PTR) MUSTDEF_RESULT (PTR) -#define FINALIZE_OPS MUSTDEF_OPS -#define FINALIZE_USE_PTR(PTR) MUSTDEF_KILL_PTR (PTR) -#define FINALIZE_CORRECT_USE set_virtual_use_link -#define FINALIZE_BASE_ZERO 0 -#define FINALIZE_BASE(VAR) get_name_decl (VAR) -#define FINALIZE_BASE_TYPE unsigned -#define FINALIZE_INITIALIZE(PTR, VAL, STMT) \ - (PTR)->def_var = (VAL); \ - (PTR)->kill_var = (VAL); \ - (PTR)->use_ptr.use = &((PTR)->kill_var);\ - link_imm_use_stmt (&((PTR)->use_ptr), \ - (VAL), (STMT)) -#include "tree-ssa-opfinalize.h" +/* Takes elements from build_v_must_defs and turns them into mustdef operands of + STMT. */ + +static inline void +finalize_ssa_v_must_def_ops (tree stmt) +{ + unsigned new_i; + struct mustdef_optype_d new_list; + mustdef_optype_p old_ops, ptr, last; + tree act; + unsigned old_base, new_base; + + new_list.next = NULL; + last = &new_list; + + old_ops = MUSTDEF_OPS (stmt); + + new_i = 0; + while (old_ops && new_i < VEC_length (tree, build_v_must_defs)) + { + act = VEC_index (tree, build_v_must_defs, new_i); + new_base = get_name_decl (act); + old_base = get_name_decl (MUSTDEF_KILL (old_ops)); + + if (old_base == new_base) + { + /* If variables are the same, reuse this node. */ + MOVE_HEAD_AFTER (old_ops, last); + set_virtual_use_link (MUSTDEF_KILL_PTR (last), stmt); + new_i++; + } + else if (old_base < new_base) + { + /* If old is less than new, old goes to the free list. */ + delink_imm_use (MUSTDEF_KILL_PTR (old_ops)); + MOVE_HEAD_TO_FREELIST (old_ops, mustdef); + } + else + { + /* This is a new operand. */ + add_mustdef_op (stmt, act, &last); + new_i++; + } + } + + /* If there is anything remaining in the build_v_must_defs list, simply emit it. */ + for ( ; new_i < VEC_length (tree, build_v_must_defs); new_i++) + add_mustdef_op (stmt, VEC_index (tree, build_v_must_defs, new_i), &last); + + last->next = NULL; + + /* If there is anything in the old list, free it. */ + if (old_ops) + { + for (ptr = old_ops; ptr; ptr = ptr->next) + delink_imm_use (MUSTDEF_KILL_PTR (ptr)); + old_ops->next = free_mustdefs; + free_mustdefs = old_ops; + } + + /* Now set the stmt's operands. */ + MUSTDEF_OPS (stmt) = new_list.next; + +#ifdef ENABLE_CHECKING + { + unsigned x = 0; + for (ptr = MUSTDEF_OPS (stmt); ptr; ptr = ptr->next) + x++; + + gcc_assert (x == VEC_length (tree, build_v_must_defs)); + } +#endif +} static void finalize_ssa_v_must_defs (tree stmt) { - /* In the presence of subvars, there may be more than one V_MUST_DEF per - statement (one for each subvar). It is a bit expensive to verify that - all must-defs in a statement belong to subvars if there is more than one - MUST-def, so we don't do it. Suffice to say, if you reach here without - having subvars, and have num >1, you have hit a bug. */ - + /* In the presence of subvars, there may be more than one V_MUST_DEF + per statement (one for each subvar). It is a bit expensive to + verify that all must-defs in a statement belong to subvars if + there is more than one must-def, so we don't do it. Suffice to + say, if you reach here without having subvars, and have num >1, + you have hit a bug. */ finalize_ssa_v_must_def_ops (stmt); VEC_truncate (tree, build_v_must_defs, 0); } @@ -673,7 +1004,6 @@ append_v_may_def (tree var) static inline void append_vuse (tree var) { - /* Don't allow duplicate entries. */ if (TREE_CODE (var) != SSA_NAME) { @@ -704,332 +1034,798 @@ append_v_must_def (tree var) } -/* Parse STMT looking for operands. OLD_OPS is the original stmt operand - cache for STMT, if it existed before. When finished, the various build_* - operand vectors will have potential operands. in them. */ - -static void -parse_ssa_operands (tree stmt) -{ - enum tree_code code; - - code = TREE_CODE (stmt); - switch (code) +/* REF is a tree that contains the entire pointer dereference + expression, if available, or NULL otherwise. ALIAS is the variable + we are asking if REF can access. OFFSET and SIZE come from the + memory access expression that generated this virtual operand. */ + +static bool +access_can_touch_variable (tree ref, tree alias, HOST_WIDE_INT offset, + HOST_WIDE_INT size) +{ + bool offsetgtz = offset > 0; + unsigned HOST_WIDE_INT uoffset = (unsigned HOST_WIDE_INT) offset; + tree base = ref ? get_base_address (ref) : NULL; + + /* If ALIAS is .GLOBAL_VAR then the memory reference REF must be + using a call-clobbered memory tag. By definition, call-clobbered + memory tags can always touch .GLOBAL_VAR. */ + if (alias == global_var) + return true; + + /* If ALIAS is an SFT, it can't be touched if the offset + and size of the access is not overlapping with the SFT offset and + size. This is only true if we are accessing through a pointer + to a type that is the same as SFT_PARENT_VAR. Otherwise, we may + be accessing through a pointer to some substruct of the + structure, and if we try to prune there, we will have the wrong + offset, and get the wrong answer. + i.e., we can't prune without more work if we have something like + + struct gcc_target + { + struct asm_out + { + const char *byte_op; + struct asm_int_op + { + const char *hi; + } aligned_op; + } asm_out; + } targetm; + + foo = &targetm.asm_out.aligned_op; + return foo->hi; + + SFT.1, which represents hi, will have SFT_OFFSET=32 because in + terms of SFT_PARENT_VAR, that is where it is. + However, the access through the foo pointer will be at offset 0. */ + if (size != -1 + && TREE_CODE (alias) == STRUCT_FIELD_TAG + && base + && TREE_TYPE (base) == TREE_TYPE (SFT_PARENT_VAR (alias)) + && !overlap_subvar (offset, size, alias, NULL)) { - case MODIFY_EXPR: - /* First get operands from the RHS. For the LHS, we use a V_MAY_DEF if - either only part of LHS is modified or if the RHS might throw, - otherwise, use V_MUST_DEF. - - ??? If it might throw, we should represent somehow that it is killed - on the fallthrough path. */ - { - tree lhs = TREE_OPERAND (stmt, 0); - int lhs_flags = opf_is_def; +#ifdef ACCESS_DEBUGGING + fprintf (stderr, "Access to "); + print_generic_expr (stderr, ref, 0); + fprintf (stderr, " may not touch "); + print_generic_expr (stderr, alias, 0); + fprintf (stderr, " in function %s\n", get_name (current_function_decl)); +#endif + return false; + } - get_expr_operands (stmt, &TREE_OPERAND (stmt, 1), opf_none); + /* Without strict aliasing, it is impossible for a component access + through a pointer to touch a random variable, unless that + variable *is* a structure or a pointer. - /* If the LHS is a VIEW_CONVERT_EXPR, it isn't changing whether - or not the entire LHS is modified; that depends on what's - inside the VIEW_CONVERT_EXPR. */ - if (TREE_CODE (lhs) == VIEW_CONVERT_EXPR) - lhs = TREE_OPERAND (lhs, 0); + That is, given p->c, and some random global variable b, + there is no legal way that p->c could be an access to b. + + Without strict aliasing on, we consider it legal to do something + like: + + struct foos { int l; }; + int foo; + static struct foos *getfoo(void); + int main (void) + { + struct foos *f = getfoo(); + f->l = 1; + foo = 2; + if (f->l == 1) + abort(); + exit(0); + } + static struct foos *getfoo(void) + { return (struct foos *)&foo; } + + (taken from 20000623-1.c) + + The docs also say/imply that access through union pointers + is legal (but *not* if you take the address of the union member, + i.e. the inverse), such that you can do + + typedef union { + int d; + } U; + + int rv; + void breakme() + { + U *rv0; + U *pretmp = (U*)&rv; + rv0 = pretmp; + rv0->d = 42; + } + To implement this, we just punt on accesses through union + pointers entirely. + */ + else if (ref + && flag_strict_aliasing + && TREE_CODE (ref) != INDIRECT_REF + && !MTAG_P (alias) + && (TREE_CODE (base) != INDIRECT_REF + || TREE_CODE (TREE_TYPE (base)) != UNION_TYPE) + && !AGGREGATE_TYPE_P (TREE_TYPE (alias)) + && TREE_CODE (TREE_TYPE (alias)) != COMPLEX_TYPE + && !POINTER_TYPE_P (TREE_TYPE (alias)) + /* When the struct has may_alias attached to it, we need not to + return true. */ + && get_alias_set (base)) + { +#ifdef ACCESS_DEBUGGING + fprintf (stderr, "Access to "); + print_generic_expr (stderr, ref, 0); + fprintf (stderr, " may not touch "); + print_generic_expr (stderr, alias, 0); + fprintf (stderr, " in function %s\n", get_name (current_function_decl)); +#endif + return false; + } - if (TREE_CODE (lhs) != ARRAY_REF - && TREE_CODE (lhs) != ARRAY_RANGE_REF - && TREE_CODE (lhs) != BIT_FIELD_REF - && TREE_CODE (lhs) != REALPART_EXPR - && TREE_CODE (lhs) != IMAGPART_EXPR) - lhs_flags |= opf_kill_def; + /* If the offset of the access is greater than the size of one of + the possible aliases, it can't be touching that alias, because it + would be past the end of the structure. */ + else if (ref + && flag_strict_aliasing + && TREE_CODE (ref) != INDIRECT_REF + && !MTAG_P (alias) + && !POINTER_TYPE_P (TREE_TYPE (alias)) + && offsetgtz + && DECL_SIZE (alias) + && TREE_CODE (DECL_SIZE (alias)) == INTEGER_CST + && uoffset > TREE_INT_CST_LOW (DECL_SIZE (alias))) + { +#ifdef ACCESS_DEBUGGING + fprintf (stderr, "Access to "); + print_generic_expr (stderr, ref, 0); + fprintf (stderr, " may not touch "); + print_generic_expr (stderr, alias, 0); + fprintf (stderr, " in function %s\n", get_name (current_function_decl)); +#endif + return false; + } - get_expr_operands (stmt, &TREE_OPERAND (stmt, 0), lhs_flags); - } - break; + return true; +} - case COND_EXPR: - get_expr_operands (stmt, &COND_EXPR_COND (stmt), opf_none); - break; - case SWITCH_EXPR: - get_expr_operands (stmt, &SWITCH_COND (stmt), opf_none); - break; +/* Add VAR to the virtual operands array. FLAGS is as in + get_expr_operands. FULL_REF is a tree that contains the entire + pointer dereference expression, if available, or NULL otherwise. + OFFSET and SIZE come from the memory access expression that + generated this virtual operand. FOR_CLOBBER is true is this is + adding a virtual operand for a call clobber. */ - case ASM_EXPR: - get_asm_expr_operands (stmt); - break; +static void +add_virtual_operand (tree var, stmt_ann_t s_ann, int flags, + tree full_ref, HOST_WIDE_INT offset, + HOST_WIDE_INT size, bool for_clobber) +{ + VEC(tree,gc) *aliases; + tree sym; + var_ann_t v_ann; + + sym = (TREE_CODE (var) == SSA_NAME ? SSA_NAME_VAR (var) : var); + v_ann = var_ann (sym); + + /* Mark statements with volatile operands. Optimizers should back + off from statements having volatile operands. */ + if (TREE_THIS_VOLATILE (sym) && s_ann) + s_ann->has_volatile_ops = true; - case RETURN_EXPR: - get_expr_operands (stmt, &TREE_OPERAND (stmt, 0), opf_none); - break; + /* If the variable cannot be modified and this is a V_MAY_DEF change + it into a VUSE. This happens when read-only variables are marked + call-clobbered and/or aliased to writable variables. So we only + check that this only happens on non-specific stores. - case GOTO_EXPR: - get_expr_operands (stmt, &GOTO_DESTINATION (stmt), opf_none); - break; + Note that if this is a specific store, i.e. associated with a + modify_expr, then we can't suppress the V_MAY_DEF, lest we run + into validation problems. - case LABEL_EXPR: - get_expr_operands (stmt, &LABEL_EXPR_LABEL (stmt), opf_none); - break; + This can happen when programs cast away const, leaving us with a + store to read-only memory. If the statement is actually executed + at runtime, then the program is ill formed. If the statement is + not executed then all is well. At the very least, we cannot ICE. */ + if ((flags & opf_non_specific) && unmodifiable_var_p (var)) + flags &= ~(opf_is_def | opf_kill_def); + + /* The variable is not a GIMPLE register. Add it (or its aliases) to + virtual operands, unless the caller has specifically requested + not to add virtual operands (used when adding operands inside an + ADDR_EXPR expression). */ + if (flags & opf_no_vops) + return; + + aliases = v_ann->may_aliases; + if (aliases == NULL) + { + /* The variable is not aliased or it is an alias tag. */ + if (flags & opf_is_def) + { + if (flags & opf_kill_def) + { + /* V_MUST_DEF for non-aliased, non-GIMPLE register + variable definitions. */ + gcc_assert (!MTAG_P (var) + || TREE_CODE (var) == STRUCT_FIELD_TAG); + append_v_must_def (var); + } + else + { + /* Add a V_MAY_DEF for call-clobbered variables and + memory tags. */ + append_v_may_def (var); + } + } + else + append_vuse (var); + } + else + { + unsigned i; + tree al; + + /* The variable is aliased. Add its aliases to the virtual + operands. */ + gcc_assert (VEC_length (tree, aliases) != 0); + + if (flags & opf_is_def) + { + + bool none_added = true; - /* These nodes contain no variable references. */ - case BIND_EXPR: - case CASE_LABEL_EXPR: - case TRY_CATCH_EXPR: - case TRY_FINALLY_EXPR: - case EH_FILTER_EXPR: - case CATCH_EXPR: - case RESX_EXPR: - break; + for (i = 0; VEC_iterate (tree, aliases, i, al); i++) + { + if (!access_can_touch_variable (full_ref, al, offset, size)) + continue; + + none_added = false; + append_v_may_def (al); + } - default: - /* Notice that if get_expr_operands tries to use &STMT as the operand - pointer (which may only happen for USE operands), we will fail in - append_use. This default will handle statements like empty - statements, or CALL_EXPRs that may appear on the RHS of a statement - or as statements themselves. */ - get_expr_operands (stmt, &stmt, opf_none); - break; + /* If the variable is also an alias tag, add a virtual + operand for it, otherwise we will miss representing + references to the members of the variable's alias set. + This fixes the bug in gcc.c-torture/execute/20020503-1.c. + + It is also necessary to add bare defs on clobbers for + SMT's, so that bare SMT uses caused by pruning all the + aliases will link up properly with calls. In order to + keep the number of these bare defs we add down to the + minimum necessary, we keep track of which SMT's were used + alone in statement vdefs or VUSEs. */ + if (v_ann->is_aliased + || none_added + || (TREE_CODE (var) == SYMBOL_MEMORY_TAG + && for_clobber + && SMT_USED_ALONE (var))) + { + /* Every bare SMT def we add should have SMT_USED_ALONE + set on it, or else we will get the wrong answer on + clobbers. */ + if (none_added + && !updating_used_alone && aliases_computed_p + && TREE_CODE (var) == SYMBOL_MEMORY_TAG) + gcc_assert (SMT_USED_ALONE (var)); + + append_v_may_def (var); + } + } + else + { + bool none_added = true; + for (i = 0; VEC_iterate (tree, aliases, i, al); i++) + { + if (!access_can_touch_variable (full_ref, al, offset, size)) + continue; + none_added = false; + append_vuse (al); + } + + /* Similarly, append a virtual uses for VAR itself, when + it is an alias tag. */ + if (v_ann->is_aliased || none_added) + append_vuse (var); + } } } -/* Create an operands cache for STMT. */ + +/* Add *VAR_P to the appropriate operand array for S_ANN. FLAGS is as in + get_expr_operands. If *VAR_P is a GIMPLE register, it will be added to + the statement's real operands, otherwise it is added to virtual + operands. */ static void -build_ssa_operands (tree stmt) +add_stmt_operand (tree *var_p, stmt_ann_t s_ann, int flags) { - stmt_ann_t ann = get_stmt_ann (stmt); - - /* Initially assume that the statement has no volatile operands, nor - makes aliased loads or stores. */ - if (ann) - { - ann->has_volatile_ops = false; - ann->makes_aliased_stores = false; - ann->makes_aliased_loads = false; - } - - start_ssa_stmt_operands (); - - parse_ssa_operands (stmt); - operand_build_sort_virtual (build_vuses); - operand_build_sort_virtual (build_v_may_defs); - operand_build_sort_virtual (build_v_must_defs); + bool is_real_op; + tree var, sym; + var_ann_t v_ann; - finalize_ssa_stmt_operands (stmt); -} + var = *var_p; + gcc_assert (SSA_VAR_P (var)); + is_real_op = is_gimple_reg (var); -/* Free any operands vectors in OPS. */ -void -free_ssa_operands (stmt_operands_p ops) -{ - ops->def_ops = NULL; - ops->use_ops = NULL; - ops->maydef_ops = NULL; - ops->mustdef_ops = NULL; - ops->vuse_ops = NULL; -} + /* If this is a real operand, the operand is either an SSA name or a + decl. Virtual operands may only be decls. */ + gcc_assert (is_real_op || DECL_P (var)); + sym = (TREE_CODE (var) == SSA_NAME ? SSA_NAME_VAR (var) : var); + v_ann = var_ann (sym); -/* Get the operands of statement STMT. Note that repeated calls to - get_stmt_operands for the same statement will do nothing until the - statement is marked modified by a call to mark_stmt_modified(). */ + /* Mark statements with volatile operands. Optimizers should back + off from statements having volatile operands. */ + if (TREE_THIS_VOLATILE (sym) && s_ann) + s_ann->has_volatile_ops = true; -void -update_stmt_operands (tree stmt) -{ - stmt_ann_t ann = get_stmt_ann (stmt); - /* If get_stmt_operands is called before SSA is initialized, dont - do anything. */ - if (!ssa_operands_active ()) - return; - /* The optimizers cannot handle statements that are nothing but a - _DECL. This indicates a bug in the gimplifier. */ - gcc_assert (!SSA_VAR_P (stmt)); + if (is_real_op) + { + /* The variable is a GIMPLE register. Add it to real operands. */ + if (flags & opf_is_def) + append_def (var_p); + else + append_use (var_p); + } + else + add_virtual_operand (var, s_ann, flags, NULL_TREE, 0, -1, false); +} - gcc_assert (ann->modified); - timevar_push (TV_TREE_OPS); +/* A subroutine of get_expr_operands to handle INDIRECT_REF, + ALIGN_INDIRECT_REF and MISALIGNED_INDIRECT_REF. - build_ssa_operands (stmt); + STMT is the statement being processed, EXPR is the INDIRECT_REF + that got us here. + + FLAGS is as in get_expr_operands. - /* Clear the modified bit for STMT. Subsequent calls to - get_stmt_operands for this statement will do nothing until the - statement is marked modified by a call to mark_stmt_modified(). */ - ann->modified = 0; + FULL_REF contains the full pointer dereference expression, if we + have it, or NULL otherwise. - timevar_pop (TV_TREE_OPS); -} + OFFSET and SIZE are the location of the access inside the + dereferenced pointer, if known. - -/* Copies virtual operands from SRC to DST. */ + RECURSE_ON_BASE should be set to true if we want to continue + calling get_expr_operands on the base pointer, and false if + something else will do it for us. */ -void -copy_virtual_operands (tree dest, tree src) +static void +get_indirect_ref_operands (tree stmt, tree expr, int flags, + tree full_ref, + HOST_WIDE_INT offset, HOST_WIDE_INT size, + bool recurse_on_base) { - tree t; - ssa_op_iter iter, old_iter; - use_operand_p use_p, u2; - def_operand_p def_p, d2; + tree *pptr = &TREE_OPERAND (expr, 0); + tree ptr = *pptr; + stmt_ann_t s_ann = stmt_ann (stmt); - build_ssa_operands (dest); + /* Stores into INDIRECT_REF operands are never killing definitions. */ + flags &= ~opf_kill_def; - /* Copy all the virtual fields. */ - FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VUSE) - append_vuse (t); - FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VMAYDEF) - append_v_may_def (t); - FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VMUSTDEF) - append_v_must_def (t); + if (SSA_VAR_P (ptr)) + { + struct ptr_info_def *pi = NULL; - if (VEC_length (tree, build_vuses) == 0 - && VEC_length (tree, build_v_may_defs) == 0 - && VEC_length (tree, build_v_must_defs) == 0) - return; + /* If PTR has flow-sensitive points-to information, use it. */ + if (TREE_CODE (ptr) == SSA_NAME + && (pi = SSA_NAME_PTR_INFO (ptr)) != NULL + && pi->name_mem_tag) + { + /* PTR has its own memory tag. Use it. */ + add_virtual_operand (pi->name_mem_tag, s_ann, flags, + full_ref, offset, size, false); + } + else + { + /* If PTR is not an SSA_NAME or it doesn't have a name + tag, use its symbol memory tag. */ + var_ann_t v_ann; - /* Now commit the virtual operands to this stmt. */ - finalize_ssa_v_must_defs (dest); - finalize_ssa_v_may_defs (dest); - finalize_ssa_vuses (dest); + /* If we are emitting debugging dumps, display a warning if + PTR is an SSA_NAME with no flow-sensitive alias + information. That means that we may need to compute + aliasing again. */ + if (dump_file + && TREE_CODE (ptr) == SSA_NAME + && pi == NULL) + { + fprintf (dump_file, + "NOTE: no flow-sensitive alias info for "); + print_generic_expr (dump_file, ptr, dump_flags); + fprintf (dump_file, " in "); + print_generic_stmt (dump_file, stmt, dump_flags); + } - /* Finally, set the field to the same values as then originals. */ + if (TREE_CODE (ptr) == SSA_NAME) + ptr = SSA_NAME_VAR (ptr); + v_ann = var_ann (ptr); - - t = op_iter_init_tree (&old_iter, src, SSA_OP_VUSE); - FOR_EACH_SSA_USE_OPERAND (use_p, dest, iter, SSA_OP_VUSE) - { - gcc_assert (!op_iter_done (&old_iter)); - SET_USE (use_p, t); - t = op_iter_next_tree (&old_iter); + if (v_ann->symbol_mem_tag) + add_virtual_operand (v_ann->symbol_mem_tag, s_ann, flags, + full_ref, offset, size, false); + } } - gcc_assert (op_iter_done (&old_iter)); - - op_iter_init_maydef (&old_iter, src, &u2, &d2); - FOR_EACH_SSA_MAYDEF_OPERAND (def_p, use_p, dest, iter) + else if (TREE_CODE (ptr) == INTEGER_CST) { - gcc_assert (!op_iter_done (&old_iter)); - SET_USE (use_p, USE_FROM_PTR (u2)); - SET_DEF (def_p, DEF_FROM_PTR (d2)); - op_iter_next_maymustdef (&u2, &d2, &old_iter); + /* If a constant is used as a pointer, we can't generate a real + operand for it but we mark the statement volatile to prevent + optimizations from messing things up. */ + if (s_ann) + s_ann->has_volatile_ops = true; + return; } - gcc_assert (op_iter_done (&old_iter)); - - op_iter_init_mustdef (&old_iter, src, &u2, &d2); - FOR_EACH_SSA_MUSTDEF_OPERAND (def_p, use_p, dest, iter) + else { - gcc_assert (!op_iter_done (&old_iter)); - SET_USE (use_p, USE_FROM_PTR (u2)); - SET_DEF (def_p, DEF_FROM_PTR (d2)); - op_iter_next_maymustdef (&u2, &d2, &old_iter); + /* Ok, this isn't even is_gimple_min_invariant. Something's broke. */ + gcc_unreachable (); } - gcc_assert (op_iter_done (&old_iter)); + /* If requested, add a USE operand for the base pointer. */ + if (recurse_on_base) + get_expr_operands (stmt, pptr, opf_none); } -/* Specifically for use in DOM's expression analysis. Given a store, we - create an artificial stmt which looks like a load from the store, this can - be used to eliminate redundant loads. OLD_OPS are the operands from the - store stmt, and NEW_STMT is the new load which represents a load of the - values stored. */ +/* A subroutine of get_expr_operands to handle TARGET_MEM_REF. */ -void -create_ssa_artficial_load_stmt (tree new_stmt, tree old_stmt) +static void +get_tmr_operands (tree stmt, tree expr, int flags) { - stmt_ann_t ann; - tree op; - ssa_op_iter iter; - use_operand_p use_p; - unsigned x; + tree tag = TMR_TAG (expr), ref; + HOST_WIDE_INT offset, size, maxsize; + subvar_t svars, sv; + stmt_ann_t s_ann = stmt_ann (stmt); - ann = get_stmt_ann (new_stmt); + /* First record the real operands. */ + get_expr_operands (stmt, &TMR_BASE (expr), opf_none); + get_expr_operands (stmt, &TMR_INDEX (expr), opf_none); - /* process the stmt looking for operands. */ - start_ssa_stmt_operands (); - parse_ssa_operands (new_stmt); + /* MEM_REFs should never be killing. */ + flags &= ~opf_kill_def; - for (x = 0; x < VEC_length (tree, build_vuses); x++) + if (TMR_SYMBOL (expr)) { - tree t = VEC_index (tree, build_vuses, x); - if (TREE_CODE (t) != SSA_NAME) + stmt_ann_t ann = stmt_ann (stmt); + add_to_addressable_set (TMR_SYMBOL (expr), &ann->addresses_taken); + } + + if (!tag) + { + /* Something weird, so ensure that we will be careful. */ + stmt_ann (stmt)->has_volatile_ops = true; + return; + } + + if (DECL_P (tag)) + { + get_expr_operands (stmt, &tag, flags); + return; + } + + ref = get_ref_base_and_extent (tag, &offset, &size, &maxsize); + gcc_assert (ref != NULL_TREE); + svars = get_subvars_for_var (ref); + for (sv = svars; sv; sv = sv->next) + { + bool exact; + if (overlap_subvar (offset, maxsize, sv->var, &exact)) { - var_ann_t ann = var_ann (t); - ann->in_vuse_list = 0; + int subvar_flags = flags; + if (!exact || size != maxsize) + subvar_flags &= ~opf_kill_def; + add_stmt_operand (&sv->var, s_ann, subvar_flags); } } - - for (x = 0; x < VEC_length (tree, build_v_may_defs); x++) +} + + +/* Add clobbering definitions for .GLOBAL_VAR or for each of the call + clobbered variables in the function. */ + +static void +add_call_clobber_ops (tree stmt, tree callee) +{ + unsigned u; + bitmap_iterator bi; + stmt_ann_t s_ann = stmt_ann (stmt); + bitmap not_read_b, not_written_b; + + /* Functions that are not const, pure or never return may clobber + call-clobbered variables. */ + if (s_ann) + s_ann->makes_clobbering_call = true; + + /* If we created .GLOBAL_VAR earlier, just use it. See compute_may_aliases + for the heuristic used to decide whether to create .GLOBAL_VAR or not. */ + if (global_var) { - tree t = VEC_index (tree, build_v_may_defs, x); - if (TREE_CODE (t) != SSA_NAME) + add_stmt_operand (&global_var, s_ann, opf_is_def); + return; + } + + /* Get info for local and module level statics. There is a bit + set for each static if the call being processed does not read + or write that variable. */ + not_read_b = callee ? ipa_reference_get_not_read_global (callee) : NULL; + not_written_b = callee ? ipa_reference_get_not_written_global (callee) : NULL; + /* Add a V_MAY_DEF operand for every call clobbered variable. */ + EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, u, bi) + { + tree var = referenced_var_lookup (u); + unsigned int escape_mask = var_ann (var)->escape_mask; + tree real_var = var; + bool not_read; + bool not_written; + + /* Not read and not written are computed on regular vars, not + subvars, so look at the parent var if this is an SFT. */ + if (TREE_CODE (var) == STRUCT_FIELD_TAG) + real_var = SFT_PARENT_VAR (var); + + not_read = not_read_b ? bitmap_bit_p (not_read_b, + DECL_UID (real_var)) : false; + not_written = not_written_b ? bitmap_bit_p (not_written_b, + DECL_UID (real_var)) : false; + gcc_assert (!unmodifiable_var_p (var)); + + clobber_stats.clobbered_vars++; + + /* See if this variable is really clobbered by this function. */ + + /* Trivial case: Things escaping only to pure/const are not + clobbered by non-pure-const, and only read by pure/const. */ + if ((escape_mask & ~(ESCAPE_TO_PURE_CONST)) == 0) { - var_ann_t ann = var_ann (t); - ann->in_v_may_def_list = 0; + tree call = get_call_expr_in (stmt); + if (call_expr_flags (call) & (ECF_CONST | ECF_PURE)) + { + add_stmt_operand (&var, s_ann, opf_none); + clobber_stats.unescapable_clobbers_avoided++; + continue; + } + else + { + clobber_stats.unescapable_clobbers_avoided++; + continue; + } + } + + if (not_written) + { + clobber_stats.static_write_clobbers_avoided++; + if (!not_read) + add_stmt_operand (&var, s_ann, opf_none); + else + clobber_stats.static_read_clobbers_avoided++; } + else + add_virtual_operand (var, s_ann, opf_is_def, NULL, 0, -1, true); } - /* Remove any virtual operands that were found. */ - VEC_truncate (tree, build_v_may_defs, 0); - VEC_truncate (tree, build_v_must_defs, 0); - VEC_truncate (tree, build_vuses, 0); +} - /* For each VDEF on the original statement, we want to create a - VUSE of the V_MAY_DEF result or V_MUST_DEF op on the new - statement. */ - FOR_EACH_SSA_TREE_OPERAND (op, old_stmt, iter, - (SSA_OP_VMAYDEF | SSA_OP_VMUSTDEF)) - append_vuse (op); - - /* Now build the operands for this new stmt. */ - finalize_ssa_stmt_operands (new_stmt); - /* All uses in this fake stmt must not be in the immediate use lists. */ - FOR_EACH_SSA_USE_OPERAND (use_p, new_stmt, iter, SSA_OP_ALL_USES) - delink_imm_use (use_p); +/* Add VUSE operands for .GLOBAL_VAR or all call clobbered variables in the + function. */ + +static void +add_call_read_ops (tree stmt, tree callee) +{ + unsigned u; + bitmap_iterator bi; + stmt_ann_t s_ann = stmt_ann (stmt); + bitmap not_read_b; + + /* if the function is not pure, it may reference memory. Add + a VUSE for .GLOBAL_VAR if it has been created. See add_referenced_var + for the heuristic used to decide whether to create .GLOBAL_VAR. */ + if (global_var) + { + add_stmt_operand (&global_var, s_ann, opf_none); + return; + } + + not_read_b = callee ? ipa_reference_get_not_read_global (callee) : NULL; + + /* Add a VUSE for each call-clobbered variable. */ + EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, u, bi) + { + tree var = referenced_var (u); + tree real_var = var; + bool not_read; + + clobber_stats.readonly_clobbers++; + + /* Not read and not written are computed on regular vars, not + subvars, so look at the parent var if this is an SFT. */ + + if (TREE_CODE (var) == STRUCT_FIELD_TAG) + real_var = SFT_PARENT_VAR (var); + + not_read = not_read_b ? bitmap_bit_p (not_read_b, DECL_UID (real_var)) + : false; + + if (not_read) + { + clobber_stats.static_readonly_clobbers_avoided++; + continue; + } + + add_stmt_operand (&var, s_ann, opf_none | opf_non_specific); + } } -void -swap_tree_operands (tree stmt, tree *exp0, tree *exp1) + +/* A subroutine of get_expr_operands to handle CALL_EXPR. */ + +static void +get_call_expr_operands (tree stmt, tree expr) { - tree op0, op1; - op0 = *exp0; - op1 = *exp1; + tree op; + int call_flags = call_expr_flags (expr); - /* If the operand cache is active, attempt to preserve the relative positions - of these two operands in their respective immediate use lists. */ - if (ssa_operands_active () && op0 != op1) + /* If aliases have been computed already, add V_MAY_DEF or V_USE + operands for all the symbols that have been found to be + call-clobbered. + + Note that if aliases have not been computed, the global effects + of calls will not be included in the SSA web. This is fine + because no optimizer should run before aliases have been + computed. By not bothering with virtual operands for CALL_EXPRs + we avoid adding superfluous virtual operands, which can be a + significant compile time sink (See PR 15855). */ + if (aliases_computed_p + && !bitmap_empty_p (call_clobbered_vars) + && !(call_flags & ECF_NOVOPS)) { - use_optype_p use0, use1, ptr; - use0 = use1 = NULL; - /* Find the 2 operands in the cache, if they are there. */ - for (ptr = USE_OPS (stmt); ptr; ptr = ptr->next) - if (USE_OP_PTR (ptr)->use == exp0) - { - use0 = ptr; - break; - } - for (ptr = USE_OPS (stmt); ptr; ptr = ptr->next) - if (USE_OP_PTR (ptr)->use == exp1) - { - use1 = ptr; - break; - } - /* If both uses don't have operand entries, there isn't much we can do - at this point. Presumably we dont need to worry about it. */ - if (use0 && use1) - { - tree *tmp = USE_OP_PTR (use1)->use; - USE_OP_PTR (use1)->use = USE_OP_PTR (use0)->use; - USE_OP_PTR (use0)->use = tmp; + /* A 'pure' or a 'const' function never call-clobbers anything. + A 'noreturn' function might, but since we don't return anyway + there is no point in recording that. */ + if (TREE_SIDE_EFFECTS (expr) + && !(call_flags & (ECF_PURE | ECF_CONST | ECF_NORETURN))) + add_call_clobber_ops (stmt, get_callee_fndecl (expr)); + else if (!(call_flags & ECF_CONST)) + add_call_read_ops (stmt, get_callee_fndecl (expr)); + } + + /* Find uses in the called function. */ + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), opf_none); + + for (op = TREE_OPERAND (expr, 1); op; op = TREE_CHAIN (op)) + get_expr_operands (stmt, &TREE_VALUE (op), opf_none); + + get_expr_operands (stmt, &TREE_OPERAND (expr, 2), opf_none); +} + + +/* Scan operands in the ASM_EXPR stmt referred to in INFO. */ + +static void +get_asm_expr_operands (tree stmt) +{ + stmt_ann_t s_ann = stmt_ann (stmt); + int noutputs = list_length (ASM_OUTPUTS (stmt)); + const char **oconstraints + = (const char **) alloca ((noutputs) * sizeof (const char *)); + int i; + tree link; + const char *constraint; + bool allows_mem, allows_reg, is_inout; + + for (i=0, link = ASM_OUTPUTS (stmt); link; ++i, link = TREE_CHAIN (link)) + { + constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); + oconstraints[i] = constraint; + parse_output_constraint (&constraint, i, 0, 0, &allows_mem, + &allows_reg, &is_inout); + + /* This should have been split in gimplify_asm_expr. */ + gcc_assert (!allows_reg || !is_inout); + + /* Memory operands are addressable. Note that STMT needs the + address of this operand. */ + if (!allows_reg && allows_mem) + { + tree t = get_base_address (TREE_VALUE (link)); + if (t && DECL_P (t) && s_ann) + add_to_addressable_set (t, &s_ann->addresses_taken); } + + get_expr_operands (stmt, &TREE_VALUE (link), opf_is_def); } - /* Now swap the data. */ - *exp0 = op1; - *exp1 = op0; + for (link = ASM_INPUTS (stmt); link; link = TREE_CHAIN (link)) + { + constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); + parse_input_constraint (&constraint, 0, 0, noutputs, 0, + oconstraints, &allows_mem, &allows_reg); + + /* Memory operands are addressable. Note that STMT needs the + address of this operand. */ + if (!allows_reg && allows_mem) + { + tree t = get_base_address (TREE_VALUE (link)); + if (t && DECL_P (t) && s_ann) + add_to_addressable_set (t, &s_ann->addresses_taken); + } + + get_expr_operands (stmt, &TREE_VALUE (link), 0); + } + + + /* Clobber memory for asm ("" : : : "memory"); */ + for (link = ASM_CLOBBERS (stmt); link; link = TREE_CHAIN (link)) + if (strcmp (TREE_STRING_POINTER (TREE_VALUE (link)), "memory") == 0) + { + unsigned i; + bitmap_iterator bi; + + /* Clobber all call-clobbered variables (or .GLOBAL_VAR if we + decided to group them). */ + if (global_var) + add_stmt_operand (&global_var, s_ann, opf_is_def); + else + EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, i, bi) + { + tree var = referenced_var (i); + add_stmt_operand (&var, s_ann, opf_is_def | opf_non_specific); + } + + /* Now clobber all addressables. */ + EXECUTE_IF_SET_IN_BITMAP (addressable_vars, 0, i, bi) + { + tree var = referenced_var (i); + + /* Subvars are explicitly represented in this list, so + we don't need the original to be added to the clobber + ops, but the original *will* be in this list because + we keep the addressability of the original + variable up-to-date so we don't screw up the rest of + the backend. */ + if (var_can_have_subvars (var) + && get_subvars_for_var (var) != NULL) + continue; + + add_stmt_operand (&var, s_ann, opf_is_def | opf_non_specific); + } + + break; + } } -/* Recursively scan the expression pointed to by EXPR_P in statement referred - to by INFO. FLAGS is one of the OPF_* constants modifying how to interpret - the operands found. */ + +/* Scan operands for the assignment expression EXPR in statement STMT. */ + +static void +get_modify_expr_operands (tree stmt, tree expr) +{ + /* First get operands from the RHS. */ + get_expr_operands (stmt, &TREE_OPERAND (expr, 1), opf_none); + + /* For the LHS, use a regular definition (OPF_IS_DEF) for GIMPLE + registers. If the LHS is a store to memory, we will either need + a preserving definition (V_MAY_DEF) or a killing definition + (V_MUST_DEF). + + Preserving definitions are those that modify a part of an + aggregate object for which no subvars have been computed (or the + reference does not correspond exactly to one of them). Stores + through a pointer are also represented with V_MAY_DEF operators. + + The determination of whether to use a preserving or a killing + definition is done while scanning the LHS of the assignment. By + default, assume that we will emit a V_MUST_DEF. */ + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), opf_is_def|opf_kill_def); +} + + +/* Recursively scan the expression pointed to by EXPR_P in statement + STMT. FLAGS is one of the OPF_* constants modifying how to + interpret the operands found. */ static void get_expr_operands (tree stmt, tree *expr_p, int flags) @@ -1048,41 +1844,42 @@ get_expr_operands (tree stmt, tree *expr_p, int flags) switch (code) { case ADDR_EXPR: - /* We could have the address of a component, array member, - etc which has interesting variable references. */ /* Taking the address of a variable does not represent a - reference to it, but the fact that the stmt takes its address will be - of interest to some passes (e.g. alias resolution). */ - add_stmt_operand (expr_p, s_ann, 0); + reference to it, but the fact that the statement takes its + address will be of interest to some passes (e.g. alias + resolution). */ + add_to_addressable_set (TREE_OPERAND (expr, 0), &s_ann->addresses_taken); - /* If the address is invariant, there may be no interesting variable - references inside. */ + /* If the address is invariant, there may be no interesting + variable references inside. */ if (is_gimple_min_invariant (expr)) return; - /* There should be no VUSEs created, since the referenced objects are - not really accessed. The only operands that we should find here - are ARRAY_REF indices which will always be real operands (GIMPLE - does not allow non-registers as array indices). */ + /* Otherwise, there may be variables referenced inside but there + should be no VUSEs created, since the referenced objects are + not really accessed. The only operands that we should find + here are ARRAY_REF indices which will always be real operands + (GIMPLE does not allow non-registers as array indices). */ flags |= opf_no_vops; - get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); return; case SSA_NAME: case STRUCT_FIELD_TAG: - case TYPE_MEMORY_TAG: + case SYMBOL_MEMORY_TAG: case NAME_MEMORY_TAG: + add_stmt_operand (expr_p, s_ann, flags); + return; + case VAR_DECL: case PARM_DECL: case RESULT_DECL: - case CONST_DECL: { subvar_t svars; - /* Add the subvars for a variable if it has subvars, to DEFS or USES. - Otherwise, add the variable itself. - Whether it goes to USES or DEFS depends on the operand flags. */ + /* Add the subvars for a variable, if it has subvars, to DEFS + or USES. Otherwise, add the variable itself. Whether it + goes to USES or DEFS depends on the operand flags. */ if (var_can_have_subvars (expr) && (svars = get_subvars_for_var (expr))) { @@ -1091,18 +1888,18 @@ get_expr_operands (tree stmt, tree *expr_p, int flags) add_stmt_operand (&sv->var, s_ann, flags); } else - { - add_stmt_operand (expr_p, s_ann, flags); - } + add_stmt_operand (expr_p, s_ann, flags); + return; } + case MISALIGNED_INDIRECT_REF: get_expr_operands (stmt, &TREE_OPERAND (expr, 1), flags); /* fall through */ case ALIGN_INDIRECT_REF: case INDIRECT_REF: - get_indirect_ref_operands (stmt, expr, flags); + get_indirect_ref_operands (stmt, expr, flags, NULL_TREE, 0, -1, true); return; case TARGET_MEM_REF: @@ -1111,56 +1908,55 @@ get_expr_operands (tree stmt, tree *expr_p, int flags) case ARRAY_REF: case ARRAY_RANGE_REF: - /* Treat array references as references to the virtual variable - representing the array. The virtual variable for an ARRAY_REF - is the VAR_DECL for the array. */ - - /* Add the virtual variable for the ARRAY_REF to VDEFS or VUSES - according to the value of IS_DEF. Recurse if the LHS of the - ARRAY_REF node is not a regular variable. */ - if (SSA_VAR_P (TREE_OPERAND (expr, 0))) - add_stmt_operand (expr_p, s_ann, flags); - else - get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); - - get_expr_operands (stmt, &TREE_OPERAND (expr, 1), opf_none); - get_expr_operands (stmt, &TREE_OPERAND (expr, 2), opf_none); - get_expr_operands (stmt, &TREE_OPERAND (expr, 3), opf_none); - return; - case COMPONENT_REF: case REALPART_EXPR: case IMAGPART_EXPR: { tree ref; HOST_WIDE_INT offset, size, maxsize; - /* This component ref becomes an access to all of the subvariables - it can touch, if we can determine that, but *NOT* the real one. - If we can't determine which fields we could touch, the recursion - will eventually get to a variable and add *all* of its subvars, or - whatever is the minimum correct subset. */ - + bool none = true; + + /* This component reference becomes an access to all of the + subvariables it can touch, if we can determine that, but + *NOT* the real one. If we can't determine which fields we + could touch, the recursion will eventually get to a + variable and add *all* of its subvars, or whatever is the + minimum correct subset. */ ref = get_ref_base_and_extent (expr, &offset, &size, &maxsize); if (SSA_VAR_P (ref) && get_subvars_for_var (ref)) - { - subvar_t svars = get_subvars_for_var (ref); + { subvar_t sv; + subvar_t svars = get_subvars_for_var (ref); + for (sv = svars; sv; sv = sv->next) { bool exact; - if (overlap_subvar (offset, maxsize, sv, &exact)) + + if (overlap_subvar (offset, maxsize, sv->var, &exact)) { int subvar_flags = flags; - if (!exact - || size != maxsize) + none = false; + if (!exact || size != maxsize) subvar_flags &= ~opf_kill_def; add_stmt_operand (&sv->var, s_ann, subvar_flags); } } + + if (!none) + flags |= opf_no_vops; } - else - get_expr_operands (stmt, &TREE_OPERAND (expr, 0), - flags & ~opf_kill_def); + else if (TREE_CODE (ref) == INDIRECT_REF) + { + get_indirect_ref_operands (stmt, ref, flags, expr, offset, + maxsize, false); + flags |= opf_no_vops; + } + + /* Even if we found subvars above we need to ensure to see + immediate uses for d in s.a[d]. In case of s.a having + a subvar or we would miss it otherwise. */ + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), + flags & ~opf_kill_def); if (code == COMPONENT_REF) { @@ -1168,8 +1964,16 @@ get_expr_operands (tree stmt, tree *expr_p, int flags) s_ann->has_volatile_ops = true; get_expr_operands (stmt, &TREE_OPERAND (expr, 2), opf_none); } + else if (code == ARRAY_REF || code == ARRAY_RANGE_REF) + { + get_expr_operands (stmt, &TREE_OPERAND (expr, 1), opf_none); + get_expr_operands (stmt, &TREE_OPERAND (expr, 2), opf_none); + get_expr_operands (stmt, &TREE_OPERAND (expr, 3), opf_none); + } + return; } + case WITH_SIZE_EXPR: /* WITH_SIZE_EXPR is a pass-through reference to its first argument, and an rvalue reference to its second argument. */ @@ -1189,26 +1993,8 @@ get_expr_operands (tree stmt, tree *expr_p, int flags) return; case MODIFY_EXPR: - { - int subflags; - tree op; - - get_expr_operands (stmt, &TREE_OPERAND (expr, 1), opf_none); - - op = TREE_OPERAND (expr, 0); - if (TREE_CODE (op) == WITH_SIZE_EXPR) - op = TREE_OPERAND (expr, 0); - if (TREE_CODE (op) == ARRAY_REF - || TREE_CODE (op) == ARRAY_RANGE_REF - || TREE_CODE (op) == REALPART_EXPR - || TREE_CODE (op) == IMAGPART_EXPR) - subflags = opf_is_def; - else - subflags = opf_is_def | opf_kill_def; - - get_expr_operands (stmt, &TREE_OPERAND (expr, 0), subflags); - return; - } + get_modify_expr_operands (stmt, expr); + return; case CONSTRUCTOR: { @@ -1225,8 +2011,13 @@ get_expr_operands (tree stmt, tree *expr_p, int flags) return; } - case TRUTH_NOT_EXPR: case BIT_FIELD_REF: + /* Stores using BIT_FIELD_REF are always preserving definitions. */ + flags &= ~opf_kill_def; + + /* Fallthru */ + + case TRUTH_NOT_EXPR: case VIEW_CONVERT_EXPR: do_unary: get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); @@ -1245,6 +2036,7 @@ get_expr_operands (tree stmt, tree *expr_p, int flags) return; } + case DOT_PROD_EXPR: case REALIGN_LOAD_EXPR: { get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); @@ -1253,443 +2045,342 @@ get_expr_operands (tree stmt, tree *expr_p, int flags) return; } - case BLOCK: - case FUNCTION_DECL: - case EXC_PTR_EXPR: - case FILTER_EXPR: - case LABEL_DECL: - /* Expressions that make no memory references. */ - return; - - default: - if (class == tcc_unary) - goto do_unary; - if (class == tcc_binary || class == tcc_comparison) - goto do_binary; - if (class == tcc_constant || class == tcc_type) - return; - } - - /* If we get here, something has gone wrong. */ -#ifdef ENABLE_CHECKING - fprintf (stderr, "unhandled expression in get_expr_operands():\n"); - debug_tree (expr); - fputs ("\n", stderr); - internal_error ("internal error"); -#endif - gcc_unreachable (); -} - - -/* Scan operands in the ASM_EXPR stmt referred to in INFO. */ - -static void -get_asm_expr_operands (tree stmt) -{ - stmt_ann_t s_ann = stmt_ann (stmt); - int noutputs = list_length (ASM_OUTPUTS (stmt)); - const char **oconstraints - = (const char **) alloca ((noutputs) * sizeof (const char *)); - int i; - tree link; - const char *constraint; - bool allows_mem, allows_reg, is_inout; - - for (i=0, link = ASM_OUTPUTS (stmt); link; ++i, link = TREE_CHAIN (link)) - { - oconstraints[i] = constraint - = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); - parse_output_constraint (&constraint, i, 0, 0, - &allows_mem, &allows_reg, &is_inout); - - /* This should have been split in gimplify_asm_expr. */ - gcc_assert (!allows_reg || !is_inout); - - /* Memory operands are addressable. Note that STMT needs the - address of this operand. */ - if (!allows_reg && allows_mem) - { - tree t = get_base_address (TREE_VALUE (link)); - if (t && DECL_P (t) && s_ann) - add_to_addressable_set (t, &s_ann->addresses_taken); - } - - get_expr_operands (stmt, &TREE_VALUE (link), opf_is_def); - } - - for (link = ASM_INPUTS (stmt); link; link = TREE_CHAIN (link)) - { - constraint - = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); - parse_input_constraint (&constraint, 0, 0, noutputs, 0, - oconstraints, &allows_mem, &allows_reg); - - /* Memory operands are addressable. Note that STMT needs the - address of this operand. */ - if (!allows_reg && allows_mem) - { - tree t = get_base_address (TREE_VALUE (link)); - if (t && DECL_P (t) && s_ann) - add_to_addressable_set (t, &s_ann->addresses_taken); - } - - get_expr_operands (stmt, &TREE_VALUE (link), 0); - } - - - /* Clobber memory for asm ("" : : : "memory"); */ - for (link = ASM_CLOBBERS (stmt); link; link = TREE_CHAIN (link)) - if (strcmp (TREE_STRING_POINTER (TREE_VALUE (link)), "memory") == 0) - { - unsigned i; - bitmap_iterator bi; - - /* Clobber all call-clobbered variables (or .GLOBAL_VAR if we - decided to group them). */ - if (global_var) - add_stmt_operand (&global_var, s_ann, opf_is_def); - else - EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, i, bi) - { - tree var = referenced_var (i); - add_stmt_operand (&var, s_ann, opf_is_def | opf_non_specific); - } - - /* Now clobber all addressables. */ - EXECUTE_IF_SET_IN_BITMAP (addressable_vars, 0, i, bi) - { - tree var = referenced_var (i); - - /* Subvars are explicitly represented in this list, so - we don't need the original to be added to the clobber - ops, but the original *will* be in this list because - we keep the addressability of the original - variable up-to-date so we don't screw up the rest of - the backend. */ - if (var_can_have_subvars (var) - && get_subvars_for_var (var) != NULL) - continue; + case BLOCK: + case FUNCTION_DECL: + case EXC_PTR_EXPR: + case FILTER_EXPR: + case LABEL_DECL: + case CONST_DECL: + case OMP_PARALLEL: + case OMP_SECTIONS: + case OMP_FOR: + case OMP_SINGLE: + case OMP_MASTER: + case OMP_ORDERED: + case OMP_CRITICAL: + case OMP_RETURN: + case OMP_CONTINUE: + /* Expressions that make no memory references. */ + return; - add_stmt_operand (&var, s_ann, opf_is_def | opf_non_specific); - } + default: + if (class == tcc_unary) + goto do_unary; + if (class == tcc_binary || class == tcc_comparison) + goto do_binary; + if (class == tcc_constant || class == tcc_type) + return; + } - break; - } + /* If we get here, something has gone wrong. */ +#ifdef ENABLE_CHECKING + fprintf (stderr, "unhandled expression in get_expr_operands():\n"); + debug_tree (expr); + fputs ("\n", stderr); +#endif + gcc_unreachable (); } -/* A subroutine of get_expr_operands to handle INDIRECT_REF, - ALIGN_INDIRECT_REF and MISALIGNED_INDIRECT_REF. */ + +/* Parse STMT looking for operands. When finished, the various + build_* operand vectors will have potential operands in them. */ static void -get_indirect_ref_operands (tree stmt, tree expr, int flags) +parse_ssa_operands (tree stmt) { - tree *pptr = &TREE_OPERAND (expr, 0); - tree ptr = *pptr; - stmt_ann_t s_ann = stmt_ann (stmt); - - /* Stores into INDIRECT_REF operands are never killing definitions. */ - flags &= ~opf_kill_def; + enum tree_code code; - if (SSA_VAR_P (ptr)) + code = TREE_CODE (stmt); + switch (code) { - struct ptr_info_def *pi = NULL; + case MODIFY_EXPR: + get_modify_expr_operands (stmt, stmt); + break; - /* If PTR has flow-sensitive points-to information, use it. */ - if (TREE_CODE (ptr) == SSA_NAME - && (pi = SSA_NAME_PTR_INFO (ptr)) != NULL - && pi->name_mem_tag) - { - /* PTR has its own memory tag. Use it. */ - add_stmt_operand (&pi->name_mem_tag, s_ann, flags); - } - else - { - /* If PTR is not an SSA_NAME or it doesn't have a name - tag, use its type memory tag. */ - var_ann_t v_ann; + case COND_EXPR: + get_expr_operands (stmt, &COND_EXPR_COND (stmt), opf_none); + break; - /* If we are emitting debugging dumps, display a warning if - PTR is an SSA_NAME with no flow-sensitive alias - information. That means that we may need to compute - aliasing again. */ - if (dump_file - && TREE_CODE (ptr) == SSA_NAME - && pi == NULL) - { - fprintf (dump_file, - "NOTE: no flow-sensitive alias info for "); - print_generic_expr (dump_file, ptr, dump_flags); - fprintf (dump_file, " in "); - print_generic_stmt (dump_file, stmt, dump_flags); - } + case SWITCH_EXPR: + get_expr_operands (stmt, &SWITCH_COND (stmt), opf_none); + break; - if (TREE_CODE (ptr) == SSA_NAME) - ptr = SSA_NAME_VAR (ptr); - v_ann = var_ann (ptr); - if (v_ann->type_mem_tag) - add_stmt_operand (&v_ann->type_mem_tag, s_ann, flags); - } - } + case ASM_EXPR: + get_asm_expr_operands (stmt); + break; - /* If a constant is used as a pointer, we can't generate a real - operand for it but we mark the statement volatile to prevent - optimizations from messing things up. */ - else if (TREE_CODE (ptr) == INTEGER_CST) - { - if (s_ann) - s_ann->has_volatile_ops = true; - return; - } + case RETURN_EXPR: + get_expr_operands (stmt, &TREE_OPERAND (stmt, 0), opf_none); + break; - /* Everything else *should* have been folded elsewhere, but users - are smarter than we in finding ways to write invalid code. We - cannot just assert here. If we were absolutely certain that we - do handle all valid cases, then we could just do nothing here. - That seems optimistic, so attempt to do something logical... */ - else if ((TREE_CODE (ptr) == PLUS_EXPR || TREE_CODE (ptr) == MINUS_EXPR) - && TREE_CODE (TREE_OPERAND (ptr, 0)) == ADDR_EXPR - && TREE_CODE (TREE_OPERAND (ptr, 1)) == INTEGER_CST) - { - /* Make sure we know the object is addressable. */ - pptr = &TREE_OPERAND (ptr, 0); - add_stmt_operand (pptr, s_ann, 0); + case GOTO_EXPR: + get_expr_operands (stmt, &GOTO_DESTINATION (stmt), opf_none); + break; - /* Mark the object itself with a VUSE. */ - pptr = &TREE_OPERAND (*pptr, 0); - get_expr_operands (stmt, pptr, flags); - return; - } + case LABEL_EXPR: + get_expr_operands (stmt, &LABEL_EXPR_LABEL (stmt), opf_none); + break; - /* Ok, this isn't even is_gimple_min_invariant. Something's broke. */ - else - gcc_unreachable (); + case BIND_EXPR: + case CASE_LABEL_EXPR: + case TRY_CATCH_EXPR: + case TRY_FINALLY_EXPR: + case EH_FILTER_EXPR: + case CATCH_EXPR: + case RESX_EXPR: + /* These nodes contain no variable references. */ + break; - /* Add a USE operand for the base pointer. */ - get_expr_operands (stmt, pptr, opf_none); + default: + /* Notice that if get_expr_operands tries to use &STMT as the + operand pointer (which may only happen for USE operands), we + will fail in add_stmt_operand. This default will handle + statements like empty statements, or CALL_EXPRs that may + appear on the RHS of a statement or as statements themselves. */ + get_expr_operands (stmt, &stmt, opf_none); + break; + } } -/* A subroutine of get_expr_operands to handle TARGET_MEM_REF. */ + +/* Create an operands cache for STMT. */ static void -get_tmr_operands (tree stmt, tree expr, int flags) +build_ssa_operands (tree stmt) { - tree tag = TMR_TAG (expr); + stmt_ann_t ann = get_stmt_ann (stmt); + + /* Initially assume that the statement has no volatile operands. */ + if (ann) + ann->has_volatile_ops = false; - /* First record the real operands. */ - get_expr_operands (stmt, &TMR_BASE (expr), opf_none); - get_expr_operands (stmt, &TMR_INDEX (expr), opf_none); + start_ssa_stmt_operands (); - /* MEM_REFs should never be killing. */ - flags &= ~opf_kill_def; + parse_ssa_operands (stmt); + operand_build_sort_virtual (build_vuses); + operand_build_sort_virtual (build_v_may_defs); + operand_build_sort_virtual (build_v_must_defs); - if (TMR_SYMBOL (expr)) - { - stmt_ann_t ann = stmt_ann (stmt); - add_to_addressable_set (TMR_SYMBOL (expr), &ann->addresses_taken); - } + finalize_ssa_stmt_operands (stmt); +} - if (tag) - get_expr_operands (stmt, &tag, flags); - else - /* Something weird, so ensure that we will be careful. */ - stmt_ann (stmt)->has_volatile_ops = true; + +/* Free any operands vectors in OPS. */ + +void +free_ssa_operands (stmt_operands_p ops) +{ + ops->def_ops = NULL; + ops->use_ops = NULL; + ops->maydef_ops = NULL; + ops->mustdef_ops = NULL; + ops->vuse_ops = NULL; } -/* A subroutine of get_expr_operands to handle CALL_EXPR. */ -static void -get_call_expr_operands (tree stmt, tree expr) +/* Get the operands of statement STMT. */ + +void +update_stmt_operands (tree stmt) { - tree op; - int call_flags = call_expr_flags (expr); + stmt_ann_t ann = get_stmt_ann (stmt); - /* If aliases have been computed already, add V_MAY_DEF or V_USE - operands for all the symbols that have been found to be - call-clobbered. - - Note that if aliases have not been computed, the global effects - of calls will not be included in the SSA web. This is fine - because no optimizer should run before aliases have been - computed. By not bothering with virtual operands for CALL_EXPRs - we avoid adding superfluous virtual operands, which can be a - significant compile time sink (See PR 15855). */ - if (aliases_computed_p - && !bitmap_empty_p (call_clobbered_vars) - && !(call_flags & ECF_NOVOPS)) - { - /* A 'pure' or a 'const' function never call-clobbers anything. - A 'noreturn' function might, but since we don't return anyway - there is no point in recording that. */ - if (TREE_SIDE_EFFECTS (expr) - && !(call_flags & (ECF_PURE | ECF_CONST | ECF_NORETURN))) - add_call_clobber_ops (stmt, get_callee_fndecl (expr)); - else if (!(call_flags & ECF_CONST)) - add_call_read_ops (stmt); - } + /* If update_stmt_operands is called before SSA is initialized, do + nothing. */ + if (!ssa_operands_active ()) + return; - /* Find uses in the called function. */ - get_expr_operands (stmt, &TREE_OPERAND (expr, 0), opf_none); + /* The optimizers cannot handle statements that are nothing but a + _DECL. This indicates a bug in the gimplifier. */ + gcc_assert (!SSA_VAR_P (stmt)); - for (op = TREE_OPERAND (expr, 1); op; op = TREE_CHAIN (op)) - get_expr_operands (stmt, &TREE_VALUE (op), opf_none); + gcc_assert (ann->modified); - get_expr_operands (stmt, &TREE_OPERAND (expr, 2), opf_none); + timevar_push (TV_TREE_OPS); + + build_ssa_operands (stmt); + /* Clear the modified bit for STMT. */ + ann->modified = 0; + + timevar_pop (TV_TREE_OPS); } -/* Add *VAR_P to the appropriate operand array for INFO. FLAGS is as in - get_expr_operands. If *VAR_P is a GIMPLE register, it will be added to - the statement's real operands, otherwise it is added to virtual - operands. */ +/* Copies virtual operands from SRC to DST. */ -static void -add_stmt_operand (tree *var_p, stmt_ann_t s_ann, int flags) +void +copy_virtual_operands (tree dest, tree src) { - bool is_real_op; - tree var, sym; - var_ann_t v_ann; + tree t; + ssa_op_iter iter, old_iter; + use_operand_p use_p, u2; + def_operand_p def_p, d2; - var = *var_p; - STRIP_NOPS (var); + build_ssa_operands (dest); + + /* Copy all the virtual fields. */ + FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VUSE) + append_vuse (t); + FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VMAYDEF) + append_v_may_def (t); + FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VMUSTDEF) + append_v_must_def (t); - /* If the operand is an ADDR_EXPR, add its operand to the list of - variables that have had their address taken in this statement. */ - if (TREE_CODE (var) == ADDR_EXPR && s_ann) + if (VEC_length (tree, build_vuses) == 0 + && VEC_length (tree, build_v_may_defs) == 0 + && VEC_length (tree, build_v_must_defs) == 0) + return; + + /* Now commit the virtual operands to this stmt. */ + finalize_ssa_v_must_defs (dest); + finalize_ssa_v_may_defs (dest); + finalize_ssa_vuses (dest); + + /* Finally, set the field to the same values as then originals. */ + t = op_iter_init_tree (&old_iter, src, SSA_OP_VUSE); + FOR_EACH_SSA_USE_OPERAND (use_p, dest, iter, SSA_OP_VUSE) + { + gcc_assert (!op_iter_done (&old_iter)); + SET_USE (use_p, t); + t = op_iter_next_tree (&old_iter); + } + gcc_assert (op_iter_done (&old_iter)); + + op_iter_init_maydef (&old_iter, src, &u2, &d2); + FOR_EACH_SSA_MAYDEF_OPERAND (def_p, use_p, dest, iter) + { + gcc_assert (!op_iter_done (&old_iter)); + SET_USE (use_p, USE_FROM_PTR (u2)); + SET_DEF (def_p, DEF_FROM_PTR (d2)); + op_iter_next_maymustdef (&u2, &d2, &old_iter); + } + gcc_assert (op_iter_done (&old_iter)); + + op_iter_init_mustdef (&old_iter, src, &u2, &d2); + FOR_EACH_SSA_MUSTDEF_OPERAND (def_p, use_p, dest, iter) { - add_to_addressable_set (TREE_OPERAND (var, 0), &s_ann->addresses_taken); - return; + gcc_assert (!op_iter_done (&old_iter)); + SET_USE (use_p, USE_FROM_PTR (u2)); + SET_DEF (def_p, DEF_FROM_PTR (d2)); + op_iter_next_maymustdef (&u2, &d2, &old_iter); } + gcc_assert (op_iter_done (&old_iter)); - /* If the original variable is not a scalar, it will be added to the list - of virtual operands. In that case, use its base symbol as the virtual - variable representing it. */ - is_real_op = is_gimple_reg (var); - if (!is_real_op && !DECL_P (var)) - var = get_virtual_var (var); +} - /* If VAR is not a variable that we care to optimize, do nothing. */ - if (var == NULL_TREE || !SSA_VAR_P (var)) - return; - sym = (TREE_CODE (var) == SSA_NAME ? SSA_NAME_VAR (var) : var); - v_ann = var_ann (sym); +/* Specifically for use in DOM's expression analysis. Given a store, we + create an artificial stmt which looks like a load from the store, this can + be used to eliminate redundant loads. OLD_OPS are the operands from the + store stmt, and NEW_STMT is the new load which represents a load of the + values stored. */ - /* Mark statements with volatile operands. Optimizers should back - off from statements having volatile operands. */ - if (TREE_THIS_VOLATILE (sym) && s_ann) - s_ann->has_volatile_ops = true; +void +create_ssa_artficial_load_stmt (tree new_stmt, tree old_stmt) +{ + stmt_ann_t ann; + tree op; + ssa_op_iter iter; + use_operand_p use_p; + unsigned x; - /* If the variable cannot be modified and this is a V_MAY_DEF change - it into a VUSE. This happens when read-only variables are marked - call-clobbered and/or aliased to writable variables. So we only - check that this only happens on non-specific stores. + ann = get_stmt_ann (new_stmt); - Note that if this is a specific store, i.e. associated with a - modify_expr, then we can't suppress the V_DEF, lest we run into - validation problems. + /* Process the stmt looking for operands. */ + start_ssa_stmt_operands (); + parse_ssa_operands (new_stmt); - This can happen when programs cast away const, leaving us with a - store to read-only memory. If the statement is actually executed - at runtime, then the program is ill formed. If the statement is - not executed then all is well. At the very least, we cannot ICE. */ - if ((flags & opf_non_specific) && unmodifiable_var_p (var)) + for (x = 0; x < VEC_length (tree, build_vuses); x++) { - gcc_assert (!is_real_op); - flags &= ~(opf_is_def | opf_kill_def); + tree t = VEC_index (tree, build_vuses, x); + if (TREE_CODE (t) != SSA_NAME) + { + var_ann_t ann = var_ann (t); + ann->in_vuse_list = 0; + } } - - if (is_real_op) + + for (x = 0; x < VEC_length (tree, build_v_may_defs); x++) { - /* The variable is a GIMPLE register. Add it to real operands. */ - if (flags & opf_is_def) - append_def (var_p); - else - append_use (var_p); + tree t = VEC_index (tree, build_v_may_defs, x); + if (TREE_CODE (t) != SSA_NAME) + { + var_ann_t ann = var_ann (t); + ann->in_v_may_def_list = 0; + } } - else - { - varray_type aliases; - /* The variable is not a GIMPLE register. Add it (or its aliases) to - virtual operands, unless the caller has specifically requested - not to add virtual operands (used when adding operands inside an - ADDR_EXPR expression). */ - if (flags & opf_no_vops) - return; + /* Remove any virtual operands that were found. */ + VEC_truncate (tree, build_v_may_defs, 0); + VEC_truncate (tree, build_v_must_defs, 0); + VEC_truncate (tree, build_vuses, 0); - aliases = v_ann->may_aliases; + /* For each VDEF on the original statement, we want to create a + VUSE of the V_MAY_DEF result or V_MUST_DEF op on the new + statement. */ + FOR_EACH_SSA_TREE_OPERAND (op, old_stmt, iter, + (SSA_OP_VMAYDEF | SSA_OP_VMUSTDEF)) + append_vuse (op); + + /* Now build the operands for this new stmt. */ + finalize_ssa_stmt_operands (new_stmt); - if (aliases == NULL) - { - /* The variable is not aliased or it is an alias tag. */ - if (flags & opf_is_def) - { - if (flags & opf_kill_def) - { - /* Only regular variables or struct fields may get a - V_MUST_DEF operand. */ - gcc_assert (!MTAG_P (var) - || TREE_CODE (var) == STRUCT_FIELD_TAG); - /* V_MUST_DEF for non-aliased, non-GIMPLE register - variable definitions. */ - append_v_must_def (var); - } - else - { - /* Add a V_MAY_DEF for call-clobbered variables and - memory tags. */ - append_v_may_def (var); - } - } - else - { - append_vuse (var); - if (s_ann && v_ann->is_alias_tag) - s_ann->makes_aliased_loads = 1; - } - } - else - { - size_t i; + /* All uses in this fake stmt must not be in the immediate use lists. */ + FOR_EACH_SSA_USE_OPERAND (use_p, new_stmt, iter, SSA_OP_ALL_USES) + delink_imm_use (use_p); +} - /* The variable is aliased. Add its aliases to the virtual - operands. */ - gcc_assert (VARRAY_ACTIVE_SIZE (aliases) != 0); - if (flags & opf_is_def) - { - /* If the variable is also an alias tag, add a virtual - operand for it, otherwise we will miss representing - references to the members of the variable's alias set. - This fixes the bug in gcc.c-torture/execute/20020503-1.c. */ - if (v_ann->is_alias_tag) - append_v_may_def (var); - - for (i = 0; i < VARRAY_ACTIVE_SIZE (aliases); i++) - append_v_may_def (VARRAY_TREE (aliases, i)); - - if (s_ann) - s_ann->makes_aliased_stores = 1; - } - else - { - /* Similarly, append a virtual uses for VAR itself, when - it is an alias tag. */ - if (v_ann->is_alias_tag) - append_vuse (var); +/* Swap operands EXP0 and EXP1 in statement STMT. No attempt is done + to test the validity of the swap operation. */ + +void +swap_tree_operands (tree stmt, tree *exp0, tree *exp1) +{ + tree op0, op1; + op0 = *exp0; + op1 = *exp1; - for (i = 0; i < VARRAY_ACTIVE_SIZE (aliases); i++) - append_vuse (VARRAY_TREE (aliases, i)); + /* If the operand cache is active, attempt to preserve the relative + positions of these two operands in their respective immediate use + lists. */ + if (ssa_operands_active () && op0 != op1) + { + use_optype_p use0, use1, ptr; + use0 = use1 = NULL; - if (s_ann) - s_ann->makes_aliased_loads = 1; - } + /* Find the 2 operands in the cache, if they are there. */ + for (ptr = USE_OPS (stmt); ptr; ptr = ptr->next) + if (USE_OP_PTR (ptr)->use == exp0) + { + use0 = ptr; + break; + } + + for (ptr = USE_OPS (stmt); ptr; ptr = ptr->next) + if (USE_OP_PTR (ptr)->use == exp1) + { + use1 = ptr; + break; + } + + /* If both uses don't have operand entries, there isn't much we can do + at this point. Presumably we don't need to worry about it. */ + if (use0 && use1) + { + tree *tmp = USE_OP_PTR (use1)->use; + USE_OP_PTR (use1)->use = USE_OP_PTR (use0)->use; + USE_OP_PTR (use0)->use = tmp; } } + + /* Now swap the data. */ + *exp0 = op1; + *exp1 = op0; } - + /* Add the base address of REF to the set *ADDRESSES_TAKEN. If *ADDRESSES_TAKEN is NULL, a new set is created. REF may be a single variable whose address has been taken or any other valid @@ -1735,199 +2426,8 @@ add_to_addressable_set (tree ref, bitmap *addresses_taken) } -/* Add clobbering definitions for .GLOBAL_VAR or for each of the call - clobbered variables in the function. */ - -static void -add_call_clobber_ops (tree stmt, tree callee) -{ - unsigned u; - tree t; - bitmap_iterator bi; - stmt_ann_t s_ann = stmt_ann (stmt); - struct stmt_ann_d empty_ann; - bitmap not_read_b, not_written_b; - - /* Functions that are not const, pure or never return may clobber - call-clobbered variables. */ - if (s_ann) - s_ann->makes_clobbering_call = true; - - /* If we created .GLOBAL_VAR earlier, just use it. See compute_may_aliases - for the heuristic used to decide whether to create .GLOBAL_VAR or not. */ - if (global_var) - { - add_stmt_operand (&global_var, s_ann, opf_is_def); - return; - } - - /* FIXME - if we have better information from the static vars - analysis, we need to make the cache call site specific. This way - we can have the performance benefits even if we are doing good - optimization. */ - - /* Get info for local and module level statics. There is a bit - set for each static if the call being processed does not read - or write that variable. */ - - not_read_b = callee ? ipa_reference_get_not_read_global (callee) : NULL; - not_written_b = callee ? ipa_reference_get_not_written_global (callee) : NULL; - - /* If cache is valid, copy the elements into the build vectors. */ - if (ssa_call_clobbered_cache_valid - && (!not_read_b || bitmap_empty_p (not_read_b)) - && (!not_written_b || bitmap_empty_p (not_written_b))) - { - for (u = 0 ; u < VEC_length (tree, clobbered_vuses); u++) - { - t = VEC_index (tree, clobbered_vuses, u); - gcc_assert (TREE_CODE (t) != SSA_NAME); - var_ann (t)->in_vuse_list = 1; - VEC_safe_push (tree, heap, build_vuses, (tree)t); - } - for (u = 0; u < VEC_length (tree, clobbered_v_may_defs); u++) - { - t = VEC_index (tree, clobbered_v_may_defs, u); - gcc_assert (TREE_CODE (t) != SSA_NAME); - var_ann (t)->in_v_may_def_list = 1; - VEC_safe_push (tree, heap, build_v_may_defs, (tree)t); - } - if (s_ann) - { - s_ann->makes_aliased_loads = clobbered_aliased_loads; - s_ann->makes_aliased_stores = clobbered_aliased_stores; - } - return; - } - - memset (&empty_ann, 0, sizeof (struct stmt_ann_d)); - - /* Add a V_MAY_DEF operand for every call clobbered variable. */ - EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, u, bi) - { - tree var = referenced_var (u); - if (unmodifiable_var_p (var)) - add_stmt_operand (&var, &empty_ann, opf_none); - else - { - bool not_read - = not_read_b ? bitmap_bit_p (not_read_b, u) : false; - bool not_written - = not_written_b ? bitmap_bit_p (not_written_b, u) : false; - - if (not_written) - { - if (!not_read) - add_stmt_operand (&var, &empty_ann, opf_none); - } - else - add_stmt_operand (&var, &empty_ann, opf_is_def); - } - } - - if ((!not_read_b || bitmap_empty_p (not_read_b)) - && (!not_written_b || bitmap_empty_p (not_written_b))) - { - clobbered_aliased_loads = empty_ann.makes_aliased_loads; - clobbered_aliased_stores = empty_ann.makes_aliased_stores; - - /* Set the flags for a stmt's annotation. */ - if (s_ann) - { - s_ann->makes_aliased_loads = empty_ann.makes_aliased_loads; - s_ann->makes_aliased_stores = empty_ann.makes_aliased_stores; - } - - /* Prepare empty cache vectors. */ - VEC_truncate (tree, clobbered_vuses, 0); - VEC_truncate (tree, clobbered_v_may_defs, 0); - - /* Now fill the clobbered cache with the values that have been found. */ - for (u = 0; u < VEC_length (tree, build_vuses); u++) - VEC_safe_push (tree, heap, clobbered_vuses, - VEC_index (tree, build_vuses, u)); - - gcc_assert (VEC_length (tree, build_vuses) - == VEC_length (tree, clobbered_vuses)); - - for (u = 0; u < VEC_length (tree, build_v_may_defs); u++) - VEC_safe_push (tree, heap, clobbered_v_may_defs, - VEC_index (tree, build_v_may_defs, u)); - - gcc_assert (VEC_length (tree, build_v_may_defs) - == VEC_length (tree, clobbered_v_may_defs)); - - ssa_call_clobbered_cache_valid = true; - } -} - - -/* Add VUSE operands for .GLOBAL_VAR or all call clobbered variables in the - function. */ - -static void -add_call_read_ops (tree stmt) -{ - unsigned u; - tree t; - bitmap_iterator bi; - stmt_ann_t s_ann = stmt_ann (stmt); - struct stmt_ann_d empty_ann; - - /* if the function is not pure, it may reference memory. Add - a VUSE for .GLOBAL_VAR if it has been created. See add_referenced_var - for the heuristic used to decide whether to create .GLOBAL_VAR. */ - if (global_var) - { - add_stmt_operand (&global_var, s_ann, opf_none); - return; - } - - /* If cache is valid, copy the elements into the build vector. */ - if (ssa_ro_call_cache_valid) - { - for (u = 0; u < VEC_length (tree, ro_call_vuses); u++) - { - t = VEC_index (tree, ro_call_vuses, u); - gcc_assert (TREE_CODE (t) != SSA_NAME); - var_ann (t)->in_vuse_list = 1; - VEC_safe_push (tree, heap, build_vuses, (tree)t); - } - if (s_ann) - s_ann->makes_aliased_loads = ro_call_aliased_loads; - return; - } - - memset (&empty_ann, 0, sizeof (struct stmt_ann_d)); - - /* Add a VUSE for each call-clobbered variable. */ - EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, u, bi) - { - tree var = referenced_var (u); - add_stmt_operand (&var, &empty_ann, opf_none | opf_non_specific); - } - - ro_call_aliased_loads = empty_ann.makes_aliased_loads; - if (s_ann) - s_ann->makes_aliased_loads = empty_ann.makes_aliased_loads; - - /* Prepare empty cache vectors. */ - VEC_truncate (tree, ro_call_vuses, 0); - - /* Now fill the clobbered cache with the values that have been found. */ - for (u = 0; u < VEC_length (tree, build_vuses); u++) - VEC_safe_push (tree, heap, ro_call_vuses, - VEC_index (tree, build_vuses, u)); - - gcc_assert (VEC_length (tree, build_vuses) - == VEC_length (tree, ro_call_vuses)); - - ssa_ro_call_cache_valid = true; -} - - /* Scan the immediate_use list for VAR making sure its linked properly. - return RTUE iof there is a problem. */ + Return TRUE if there is a problem and emit an error message to F. */ bool verify_imm_links (FILE *f, tree var) @@ -1960,7 +2460,9 @@ verify_imm_links (FILE *f, tree var) prev = ptr; ptr = ptr->next; - /* Avoid infinite loops. 50,000,000 uses probably indicates a problem. */ + + /* Avoid infinite loops. 50,000,000 uses probably indicates a + problem. */ if (count++ > 50000000) goto error; } @@ -2018,14 +2520,18 @@ dump_immediate_uses_for (FILE *file, tree var) FOR_EACH_IMM_USE_FAST (use_p, iter, var) { - if (!is_gimple_reg (USE_FROM_PTR (use_p))) - print_generic_stmt (file, USE_STMT (use_p), TDF_VOPS); + if (use_p->stmt == NULL && use_p->use == NULL) + fprintf (file, "***end of stmt iterator marker***\n"); else - print_generic_stmt (file, USE_STMT (use_p), TDF_SLIM); + if (!is_gimple_reg (USE_FROM_PTR (use_p))) + print_generic_stmt (file, USE_STMT (use_p), TDF_VOPS); + else + print_generic_stmt (file, USE_STMT (use_p), TDF_SLIM); } fprintf(file, "\n"); } + /* Dump all the immediate uses to FILE. */ void @@ -2053,6 +2559,7 @@ debug_immediate_uses (void) dump_immediate_uses (stderr); } + /* Dump def-use edges on stderr. */ void @@ -2060,4 +2567,5 @@ debug_immediate_uses_for (tree var) { dump_immediate_uses_for (stderr, var); } + #include "gt-tree-ssa-operands.h"