/* Instruction scheduling pass. This file contains definitions used
internally in the scheduler.
- Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+ Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
+ 2001, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
This file is part of GCC.
#include "basic-block.h"
/* For reg_note. */
#include "rtl.h"
+#include "df.h"
/* Pointer to data describing the current DFA state. */
extern state_t curr_state;
/* Type to represent weakness of speculative dependence. */
typedef int dw_t;
+extern enum reg_note ds_to_dk (ds_t);
+extern ds_t dk_to_ds (enum reg_note);
+
+/* Information about the dependency. */
+struct _dep
+{
+ /* Producer. */
+ rtx pro;
+
+ /* Consumer. */
+ rtx con;
+
+ /* Dependency kind (aka dependency major type). This field is superseded
+ by STATUS below. Though, it is still in place because all the backends
+ use it. */
+ enum reg_note kind;
+
+ /* Dependency status. This field holds all dependency types and additional
+ information for speculative dependencies. */
+ ds_t status;
+};
+typedef struct _dep *dep_t;
+
+#define DEP_PRO(D) ((D)->pro)
+#define DEP_CON(D) ((D)->con)
+#define DEP_KIND(D) ((D)->kind)
+#define DEP_STATUS(D) ((D)->status)
+
+/* Functions to work with dep. */
+
+extern void init_dep (dep_t, rtx, rtx, enum reg_note);
+
+/* Definition of this struct resides below. */
+struct _dep_node;
+
+/* A link in the dependency list. This is essentially an equivalent of a
+ single {INSN, DEPS}_LIST rtx. */
+struct _dep_link
+{
+ /* Dep node with all the data. */
+ struct _dep_node *node;
+
+ /* Next link in the list. For the last one it is NULL. */
+ struct _dep_link *next;
+
+ /* Pointer to the next field of the previous link in the list.
+ For the first link this points to the deps_list->first.
+
+ With help of this field it is easy to remove and insert links to the
+ list. */
+ struct _dep_link **prev_nextp;
+};
+typedef struct _dep_link *dep_link_t;
+
+#define DEP_LINK_NODE(N) ((N)->node)
+#define DEP_LINK_NEXT(N) ((N)->next)
+#define DEP_LINK_PREV_NEXTP(N) ((N)->prev_nextp)
+
+/* Macros to work dep_link. For most usecases only part of the dependency
+ information is need. These macros conveniently provide that piece of
+ information. */
+
+#define DEP_LINK_DEP(N) (DEP_NODE_DEP (DEP_LINK_NODE (N)))
+#define DEP_LINK_PRO(N) (DEP_PRO (DEP_LINK_DEP (N)))
+#define DEP_LINK_CON(N) (DEP_CON (DEP_LINK_DEP (N)))
+#define DEP_LINK_KIND(N) (DEP_KIND (DEP_LINK_DEP (N)))
+#define DEP_LINK_STATUS(N) (DEP_STATUS (DEP_LINK_DEP (N)))
+
+void debug_dep_links (dep_link_t);
+
+/* A list of dep_links. */
+struct _deps_list
+{
+ dep_link_t first;
+};
+typedef struct _deps_list *deps_list_t;
+
+#define DEPS_LIST_FIRST(L) ((L)->first)
+
+/* Macro to walk through deps_list. */
+#define FOR_EACH_DEP_LINK(LINK, LIST) \
+ for ((LINK) = DEPS_LIST_FIRST (LIST); \
+ (LINK) != NULL; \
+ (LINK) = DEP_LINK_NEXT (LINK))
+
+/* Functions to work with deps_list. */
+
+deps_list_t create_deps_list (bool);
+void free_deps_list (deps_list_t);
+void delete_deps_list (deps_list_t);
+bool deps_list_empty_p (deps_list_t);
+void debug_deps_list (deps_list_t);
+void add_back_dep_to_deps_list (deps_list_t, dep_t);
+dep_link_t find_link_by_pro_in_deps_list (deps_list_t, rtx);
+dep_link_t find_link_by_con_in_deps_list (deps_list_t, rtx);
+void copy_deps_list_change_con (deps_list_t, deps_list_t, rtx);
+
+void move_dep_link (dep_link_t, deps_list_t);
+
+/* Suppose we have a dependence Y between insn pro1 and con1, where pro1 has
+ additional dependents con0 and con2, and con1 is dependent on additional
+ insns pro0 and pro1:
+
+ .con0 pro0
+ . ^ |
+ . | |
+ . | |
+ . X A
+ . | |
+ . | |
+ . | V
+ .pro1--Y-->con1
+ . | ^
+ . | |
+ . | |
+ . Z B
+ . | |
+ . | |
+ . V |
+ .con2 pro2
+
+ This is represented using a "dep_node" for each dependence arc, which are
+ connected as follows (diagram is centered around Y which is fully shown;
+ other dep_nodes shown partially):
+
+ . +------------+ +--------------+ +------------+
+ . : dep_node X : | dep_node Y | : dep_node Z :
+ . : : | | : :
+ . : : | | : :
+ . : forw : | forw | : forw :
+ . : +--------+ : | +--------+ | : +--------+ :
+ forw_deps : |dep_link| : | |dep_link| | : |dep_link| :
+ +-----+ : | +----+ | : | | +----+ | | : | +----+ | :
+ |first|----->| |next|-+------+->| |next|-+--+----->| |next|-+--->NULL
+ +-----+ : | +----+ | : | | +----+ | | : | +----+ | :
+ . ^ ^ : | ^ | : | | ^ | | : | | :
+ . | | : | | | : | | | | | : | | :
+ . | +--<----+--+ +--+---<--+--+--+ +--+--+--<---+--+ | :
+ . | : | | | : | | | | | : | | | :
+ . | : | +----+ | : | | +----+ | | : | +----+ | :
+ . | : | |prev| | : | | |prev| | | : | |prev| | :
+ . | : | |next| | : | | |next| | | : | |next| | :
+ . | : | +----+ | : | | +----+ | | : | +----+ | :
+ . | : | | :<-+ | | | |<-+ : | | :<-+
+ . | : | +----+ | : | | | +----+ | | | : | +----+ | : |
+ . | : | |node|-+----+ | | |node|-+--+--+ : | |node|-+----+
+ . | : | +----+ | : | | +----+ | | : | +----+ | :
+ . | : | | : | | | | : | | :
+ . | : +--------+ : | +--------+ | : +--------+ :
+ . | : : | | : :
+ . | : SAME pro1 : | +--------+ | : SAME pro1 :
+ . | : DIFF con0 : | |dep | | : DIFF con2 :
+ . | : : | | | | : :
+ . | | | +----+ | |
+ .RTX<------------------------+--+-|pro1| | |
+ .pro1 | | +----+ | |
+ . | | | |
+ . | | +----+ | |
+ .RTX<------------------------+--+-|con1| | |
+ .con1 | | +----+ | |
+ . | | | | |
+ . | | | +----+ | |
+ . | | | |kind| | |
+ . | | | +----+ | |
+ . | : : | | |stat| | | : :
+ . | : DIFF pro0 : | | +----+ | | : DIFF pro2 :
+ . | : SAME con1 : | | | | : SAME con1 :
+ . | : : | +--------+ | : :
+ . | : : | | : :
+ . | : back : | back | : back :
+ . v : +--------+ : | +--------+ | : +--------+ :
+ back_deps : |dep_link| : | |dep_link| | : |dep_link| :
+ +-----+ : | +----+ | : | | +----+ | | : | +----+ | :
+ |first|----->| |next|-+------+->| |next|-+--+----->| |next|-+--->NULL
+ +-----+ : | +----+ | : | | +----+ | | : | +----+ | :
+ . ^ : | ^ | : | | ^ | | : | | :
+ . | : | | | : | | | | | : | | :
+ . +--<----+--+ +--+---<--+--+--+ +--+--+--<---+--+ | :
+ . : | | | : | | | | | : | | | :
+ . : | +----+ | : | | +----+ | | : | +----+ | :
+ . : | |prev| | : | | |prev| | | : | |prev| | :
+ . : | |next| | : | | |next| | | : | |next| | :
+ . : | +----+ | : | | +----+ | | : | +----+ | :
+ . : | | :<-+ | | | |<-+ : | | :<-+
+ . : | +----+ | : | | | +----+ | | | : | +----+ | : |
+ . : | |node|-+----+ | | |node|-+--+--+ : | |node|-+----+
+ . : | +----+ | : | | +----+ | | : | +----+ | :
+ . : | | : | | | | : | | :
+ . : +--------+ : | +--------+ | : +--------+ :
+ . : : | | : :
+ . : dep_node A : | dep_node Y | : dep_node B :
+ . +------------+ +--------------+ +------------+
+*/
+
+struct _dep_node
+{
+ /* Backward link. */
+ struct _dep_link back;
+
+ /* The dep. */
+ struct _dep dep;
+
+ /* Forward link. */
+ struct _dep_link forw;
+};
+typedef struct _dep_node *dep_node_t;
+
+#define DEP_NODE_BACK(N) (&(N)->back)
+#define DEP_NODE_DEP(N) (&(N)->dep)
+#define DEP_NODE_FORW(N) (&(N)->forw)
+
/* Describe state of dependencies used during sched_analyze phase. */
struct deps
{
/* An EXPR_LIST containing all MEM rtx's which are pending writes. */
rtx pending_write_mems;
- /* Indicates the combined length of the two pending lists. We must prevent
- these lists from ever growing too large since the number of dependencies
- produced is at least O(N*N), and execution time is at least O(4*N*N), as
- a function of the length of these pending lists. */
- int pending_lists_length;
+ /* We must prevent the above lists from ever growing too large since
+ the number of dependencies produced is at least O(N*N),
+ and execution time is at least O(4*N*N), as a function of the
+ length of these pending lists. */
+
+ /* Indicates the length of the pending_read list. */
+ int pending_read_list_length;
+
+ /* Indicates the length of the pending_write list. */
+ int pending_write_list_length;
/* Length of the pending memory flush list. Large functions with no
calls may build up extremely large lists. */
parameter. */
void (*fix_recovery_cfg) (int, int, int);
-#ifdef ENABLE_CHECKING
- /* If the second parameter is zero, return nonzero, if block is head of the
- region.
- If the second parameter is nonzero, return nonzero, if block is leaf of
- the region.
- global_live_at_start should not change in region heads and
- global_live_at_end should not change in region leafs due to scheduling. */
- int (*region_head_or_leaf_p) (basic_block, int);
-#endif
-
/* ??? FIXME: should use straight bitfields inside sched_info instead of
this flag field. */
unsigned int flags;
struct haifa_insn_data
{
- /* A list of insns which depend on the instruction. Unlike LOG_LINKS,
+ /* NB: We can't place 'struct _deps_list' here instead of deps_list_t into
+ h_i_d because when h_i_d extends, addresses of the deps_list->first
+ change without updating deps_list->first->next->prev_nextp. Thus
+ BACK_DEPS and RESOLVED_BACK_DEPS are allocated on the heap and FORW_DEPS
+ list is allocated on the obstack. */
+
+ /* A list of backward dependencies. The insn is a consumer of all the
+ deps mentioned here. */
+ deps_list_t back_deps;
+
+ /* A list of insns which depend on the instruction. Unlike 'back_deps',
it represents forward dependencies. */
- rtx depend;
+ deps_list_t forw_deps;
/* A list of scheduled producers of the instruction. Links are being moved
- from LOG_LINKS to RESOLVED_DEPS during scheduling. */
- rtx resolved_deps;
-
- /* The line number note in effect for each insn. For line number
- notes, this indicates whether the note may be reused. */
- rtx line_note;
-
+ from 'back_deps' to 'resolved_back_deps' while scheduling. */
+ deps_list_t resolved_back_deps;
+
/* Logical uid gives the original ordering of the insns. */
int luid;
unsigned int fed_by_spec_load : 1;
unsigned int is_load_insn : 1;
- /* Nonzero if priority has been computed already. */
- unsigned int priority_known : 1;
+ /* '> 0' if priority is valid,
+ '== 0' if priority was not yet computed,
+ '< 0' if priority in invalid and should be recomputed. */
+ signed char priority_status;
/* Nonzero if instruction has internal dependence
(e.g. add_dependence was invoked with (insn == elem)). */
unsigned int has_internal_dep : 1;
- /* What speculations are neccessary to apply to schedule the instruction. */
+ /* What speculations are necessary to apply to schedule the instruction. */
ds_t todo_spec;
/* What speculations were already applied. */
ds_t done_spec;
};
extern struct haifa_insn_data *h_i_d;
-/* Used only if (current_sched_info->flags & USE_GLAT) != 0.
- These regsets store global_live_at_{start, end} information
- for each basic block. */
-extern regset *glat_start, *glat_end;
/* Accessor macros for h_i_d. There are more in haifa-sched.c and
sched-rgn.c. */
-#define INSN_DEPEND(INSN) (h_i_d[INSN_UID (INSN)].depend)
-#define RESOLVED_DEPS(INSN) (h_i_d[INSN_UID (INSN)].resolved_deps)
+#define INSN_BACK_DEPS(INSN) (h_i_d[INSN_UID (INSN)].back_deps)
+#define INSN_FORW_DEPS(INSN) (h_i_d[INSN_UID (INSN)].forw_deps)
+#define INSN_RESOLVED_BACK_DEPS(INSN) \
+ (h_i_d[INSN_UID (INSN)].resolved_back_deps)
#define INSN_LUID(INSN) (h_i_d[INSN_UID (INSN)].luid)
#define CANT_MOVE(insn) (h_i_d[INSN_UID (insn)].cant_move)
#define INSN_DEP_COUNT(INSN) (h_i_d[INSN_UID (INSN)].dep_count)
#define INSN_PRIORITY(INSN) (h_i_d[INSN_UID (INSN)].priority)
-#define INSN_PRIORITY_KNOWN(INSN) (h_i_d[INSN_UID (INSN)].priority_known)
-#define INSN_COST(INSN) (h_i_d[INSN_UID (INSN)].cost)
+#define INSN_PRIORITY_STATUS(INSN) (h_i_d[INSN_UID (INSN)].priority_status)
+#define INSN_PRIORITY_KNOWN(INSN) (INSN_PRIORITY_STATUS (INSN) > 0)
#define INSN_REG_WEIGHT(INSN) (h_i_d[INSN_UID (INSN)].reg_weight)
#define HAS_INTERNAL_DEP(INSN) (h_i_d[INSN_UID (INSN)].has_internal_dep)
#define TODO_SPEC(INSN) (h_i_d[INSN_UID (INSN)].todo_spec)
#define RECOVERY_BLOCK(INSN) (h_i_d[INSN_UID (INSN)].recovery_block)
#define ORIG_PAT(INSN) (h_i_d[INSN_UID (INSN)].orig_pat)
-/* DEP_STATUS of the link incapsulates information, that is needed for
- speculative scheduling. Namely, it is 4 integers in the range
+/* INSN is either a simple or a branchy speculation check. */
+#define IS_SPECULATION_CHECK_P(INSN) (RECOVERY_BLOCK (INSN) != NULL)
+
+/* INSN is a speculation check that will simply reexecute the speculatively
+ scheduled instruction if the speculation fails. */
+#define IS_SPECULATION_SIMPLE_CHECK_P(INSN) \
+ (RECOVERY_BLOCK (INSN) == EXIT_BLOCK_PTR)
+
+/* INSN is a speculation check that will branch to RECOVERY_BLOCK if the
+ speculation fails. Insns in that block will reexecute the speculatively
+ scheduled code and then will return immediately after INSN thus preserving
+ semantics of the program. */
+#define IS_SPECULATION_BRANCHY_CHECK_P(INSN) \
+ (RECOVERY_BLOCK (INSN) != NULL && RECOVERY_BLOCK (INSN) != EXIT_BLOCK_PTR)
+
+/* Dep status (aka ds_t) of the link encapsulates information, that is needed
+ for speculative scheduling. Namely, it is 4 integers in the range
[0, MAX_DEP_WEAK] and 3 bits.
The integers correspond to the probability of the dependence to *not*
exist, it is the probability, that overcoming of this dependence will
to know just the major type of all the dependence between two instructions,
as only true dependence can be overcome.
There also is the 4-th bit in the DEP_STATUS (HARD_DEP), that is reserved
- for using to describe instruction's status. It is set whenever instuction
- has at least one dependence, that cannot be overcome.
+ for using to describe instruction's status. It is set whenever instruction
+ has at least one dependence, that cannot be overcame.
See also: check_dep_status () in sched-deps.c . */
-#define DEP_STATUS(LINK) XINT (LINK, 2)
/* We exclude sign bit. */
#define BITS_PER_DEP_STATUS (HOST_BITS_PER_INT - 1)
/* The following defines provide numerous constants used to distinguish between
different types of speculative dependencies. */
-/* Dependence can be overcomed with generation of new data speculative
+/* Dependence can be overcome with generation of new data speculative
instruction. */
#define BEGIN_DATA (((ds_t) DEP_WEAK_MASK) << BEGIN_DATA_BITS_OFFSET)
/* This dependence is to the instruction in the recovery block, that was
formed to recover after data-speculation failure.
- Thus, this dependence can overcomed with generating of the copy of
+ Thus, this dependence can overcome with generating of the copy of
this instruction in the recovery block. */
#define BE_IN_DATA (((ds_t) DEP_WEAK_MASK) << BE_IN_DATA_BITS_OFFSET)
-/* Dependence can be overcomed with generation of new control speculative
+/* Dependence can be overcome with generation of new control speculative
instruction. */
#define BEGIN_CONTROL (((ds_t) DEP_WEAK_MASK) << BEGIN_CONTROL_BITS_OFFSET)
/* This dependence is to the instruction in the recovery block, that was
formed to recover after control-speculation failure.
- Thus, this dependence can overcomed with generating of the copy of
+ Thus, this dependence can be overcome with generating of the copy of
this instruction in the recovery block. */
#define BE_IN_CONTROL (((ds_t) DEP_WEAK_MASK) << BE_IN_CONTROL_BITS_OFFSET)
-/* Few convinient combinations. */
+/* A few convenient combinations. */
#define BEGIN_SPEC (BEGIN_DATA | BEGIN_CONTROL)
#define DATA_SPEC (BEGIN_DATA | BE_IN_DATA)
#define CONTROL_SPEC (BEGIN_CONTROL | BE_IN_CONTROL)
DO_SPECULATION = USE_DEPS_LIST << 1,
SCHED_RGN = DO_SPECULATION << 1,
SCHED_EBB = SCHED_RGN << 1,
- /* Detach register live information from basic block headers.
- This is necessary to invoke functions, that change CFG (e.g. split_edge).
- Requires USE_GLAT. */
- DETACH_LIFE_INFO = SCHED_EBB << 1,
- /* Save register live information from basic block headers to
- glat_{start, end} arrays. */
- USE_GLAT = DETACH_LIFE_INFO << 1
+ /* Scheduler can possible create new basic blocks. Used for assertions. */
+ NEW_BBS = SCHED_EBB << 1
};
enum SPEC_SCHED_FLAGS {
PREFER_NON_CONTROL_SPEC = PREFER_NON_DATA_SPEC << 1
};
-#define NOTE_NOT_BB_P(NOTE) (NOTE_P (NOTE) && (NOTE_LINE_NUMBER (NOTE) \
+#define NOTE_NOT_BB_P(NOTE) (NOTE_P (NOTE) && (NOTE_KIND (NOTE) \
!= NOTE_INSN_BASIC_BLOCK))
extern FILE *sched_dump;
extern void free_deps (struct deps *);
extern void init_deps_global (void);
extern void finish_deps_global (void);
-extern void add_forw_dep (rtx, rtx);
+extern void add_forw_dep (dep_link_t);
extern void compute_forward_dependences (rtx, rtx);
-extern rtx find_insn_list (rtx, rtx);
extern void init_dependency_caches (int);
extern void free_dependency_caches (void);
extern void extend_dependency_caches (int, bool);
enum reg_note, ds_t);
extern void add_or_update_back_forw_dep (rtx, rtx, enum reg_note, ds_t);
extern void add_back_forw_dep (rtx, rtx, enum reg_note, ds_t);
-extern void delete_back_forw_dep (rtx, rtx);
+extern void delete_back_forw_dep (dep_link_t);
extern dw_t get_dep_weak (ds_t, ds_t);
extern ds_t set_dep_weak (ds_t, ds_t, dw_t);
extern ds_t ds_merge (ds_t, ds_t);
extern void get_ebb_head_tail (basic_block, basic_block, rtx *, rtx *);
extern int no_real_insns_p (rtx, rtx);
-extern void rm_line_notes (rtx, rtx);
-extern void save_line_notes (int, rtx, rtx);
-extern void restore_line_notes (rtx, rtx);
-extern void rm_redundant_line_notes (void);
extern void rm_other_notes (rtx, rtx);
-extern int insn_cost (rtx, rtx, rtx);
+extern int insn_cost (rtx);
+extern int dep_cost (dep_t);
extern int set_priorities (rtx, rtx);
extern void schedule_block (basic_block *, int);
extern void * xrecalloc (void *, size_t, size_t, size_t);
extern void unlink_bb_notes (basic_block, basic_block);
extern void add_block (basic_block, basic_block);
-extern void attach_life_info (void);
+extern rtx bb_note (basic_block);
-#ifdef ENABLE_CHECKING
-extern void check_reg_live (bool);
-#endif
+/* Functions in sched-rgn.c. */
+extern void debug_dependencies (rtx, rtx);
#endif /* GCC_SCHED_INT_H */