+Fri Jan 29 21:00:56 1999 Bob Manson <manson@charmed.cygnus.com>
+
+ * resource.c, resource.h: New files.
+
+ * haifa-sched.c (regno_use_in): Moved to rtlanal.c.
+ (split_block_insns): Moved to recog.c.
+ (update_flow_info): Make public.
+
+ * reorg.c: Moved the functions dealing with computing resource
+ usage to resource.c.
+
+ * sched.c (regno_use_in): Moved to rtlanal.c.
+ (update_flow_info): Make public.
+ (schedule_insns): Use split_block_insns.
+
+ * recog.c (split_block_insns): New function.
+
Tue Feb 2 22:03:26 1999 David Edelsohn <edelsohn@mhpcc.edu>
* rs6000/linux.h (LINK_START_DEFAULT_SPEC): Delete, unused.
static int new_sometimes_live PROTO ((struct sometimes *, int, int));
static void finish_sometimes_live PROTO ((struct sometimes *, int));
static int schedule_block PROTO ((int, int));
-static rtx regno_use_in PROTO ((int, rtx));
static void split_hard_reg_notes PROTO ((rtx, rtx, rtx));
static void new_insn_dead_notes PROTO ((rtx, rtx, rtx, rtx));
static void update_n_sets PROTO ((rtx, int));
-static void update_flow_info PROTO ((rtx, rtx, rtx, rtx));
static char *safe_concat PROTO ((char *, char *, char *));
static int insn_issue_delay PROTO ((rtx));
static int birthing_insn_p PROTO ((rtx));
static int set_priorities PROTO ((int));
static void init_rtx_vector PROTO ((rtx **, rtx *, int, int));
static void schedule_region PROTO ((int));
-static void split_block_insns PROTO ((int));
#endif /* INSN_SCHEDULING */
\f
FREE_REG_SET (reg_pending_sets);
}
-/* Subroutine of split_hard_reg_notes. Searches X for any reference to
- REGNO, returning the rtx of the reference found if any. Otherwise,
- returns 0. */
-
-static rtx
-regno_use_in (regno, x)
- int regno;
- rtx x;
-{
- register char *fmt;
- int i, j;
- rtx tem;
-
- if (GET_CODE (x) == REG && REGNO (x) == regno)
- return x;
-
- fmt = GET_RTX_FORMAT (GET_CODE (x));
- for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
- {
- if (fmt[i] == 'e')
- {
- if ((tem = regno_use_in (regno, XEXP (x, i))))
- return tem;
- }
- else if (fmt[i] == 'E')
- for (j = XVECLEN (x, i) - 1; j >= 0; j--)
- if ((tem = regno_use_in (regno, XVECEXP (x, i, j))))
- return tem;
- }
-
- return 0;
-}
-
/* Subroutine of update_flow_info. Determines whether any new REG_NOTEs are
needed for the hard register mentioned in the note. This can happen
if the reference to the hard register in the original insn was split into
the insns from FIRST to LAST inclusive that were created by splitting
ORIG_INSN. NOTES are the original REG_NOTES. */
-static void
+void
update_flow_info (notes, first, last, orig_insn)
rtx notes;
rtx first, last;
}
}
-/* Do the splitting of insns in the block b. */
-
-static void
-split_block_insns (b)
- int b;
-{
- rtx insn, next;
-
- for (insn = BLOCK_HEAD (b);; insn = next)
- {
- rtx set, last, first, notes;
-
- /* Can't use `next_real_insn' because that
- might go across CODE_LABELS and short-out basic blocks. */
- next = NEXT_INSN (insn);
- if (GET_CODE (insn) != INSN)
- {
- if (insn == BLOCK_END (b))
- break;
-
- continue;
- }
-
- /* Don't split no-op move insns. These should silently disappear
- later in final. Splitting such insns would break the code
- that handles REG_NO_CONFLICT blocks. */
- set = single_set (insn);
- if (set && rtx_equal_p (SET_SRC (set), SET_DEST (set)))
- {
- if (insn == BLOCK_END (b))
- break;
-
- /* Nops get in the way while scheduling, so delete them now if
- register allocation has already been done. It is too risky
- to try to do this before register allocation, and there are
- unlikely to be very many nops then anyways. */
- if (reload_completed)
- {
- PUT_CODE (insn, NOTE);
- NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
- NOTE_SOURCE_FILE (insn) = 0;
- }
-
- continue;
- }
-
- /* Split insns here to get max fine-grain parallelism. */
- first = PREV_INSN (insn);
- notes = REG_NOTES (insn);
- last = try_split (PATTERN (insn), insn, 1);
- if (last != insn)
- {
- /* try_split returns the NOTE that INSN became. */
- first = NEXT_INSN (first);
- update_flow_info (notes, first, last, insn);
-
- PUT_CODE (insn, NOTE);
- NOTE_SOURCE_FILE (insn) = 0;
- NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
- if (insn == BLOCK_HEAD (b))
- BLOCK_HEAD (b) = first;
- if (insn == BLOCK_END (b))
- {
- BLOCK_END (b) = last;
- break;
- }
- }
-
- if (insn == BLOCK_END (b))
- break;
- }
-}
-
/* The one entry point in this file. DUMP_FILE is the dump file for
this pass. */
/* do the splitting first for all blocks */
for (b = 0; b < n_basic_blocks; b++)
- split_block_insns (b);
+ split_block_insns (b, 1);
max_uid = (get_max_uid () + 1);
#include "flags.h"
#include "real.h"
#include "toplev.h"
+#include "basic-block.h"
#ifndef STACK_PUSH_CODE
#ifdef STACK_GROWS_DOWNWARD
}
#endif /* REGISTER_CONSTRAINTS */
+\f
+/* Do the splitting of insns in the block B. Only try to actually split if
+ DO_SPLIT is true; otherwise, just remove nops. */
+
+void
+split_block_insns (b, do_split)
+ int b;
+ int do_split;
+{
+ rtx insn, next;
+
+ for (insn = BLOCK_HEAD (b);; insn = next)
+ {
+ rtx set;
+
+ /* Can't use `next_real_insn' because that
+ might go across CODE_LABELS and short-out basic blocks. */
+ next = NEXT_INSN (insn);
+ if (GET_CODE (insn) != INSN)
+ {
+ if (insn == BLOCK_END (b))
+ break;
+
+ continue;
+ }
+
+ /* Don't split no-op move insns. These should silently disappear
+ later in final. Splitting such insns would break the code
+ that handles REG_NO_CONFLICT blocks. */
+ set = single_set (insn);
+ if (set && rtx_equal_p (SET_SRC (set), SET_DEST (set)))
+ {
+ if (insn == BLOCK_END (b))
+ break;
+
+ /* Nops get in the way while scheduling, so delete them now if
+ register allocation has already been done. It is too risky
+ to try to do this before register allocation, and there are
+ unlikely to be very many nops then anyways. */
+ if (reload_completed)
+ {
+
+ PUT_CODE (insn, NOTE);
+ NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
+ NOTE_SOURCE_FILE (insn) = 0;
+ }
+
+ continue;
+ }
+
+ if (do_split)
+ {
+ /* Split insns here to get max fine-grain parallelism. */
+ rtx first = PREV_INSN (insn);
+ rtx notes = REG_NOTES (insn);
+ rtx last = try_split (PATTERN (insn), insn, 1);
+
+ if (last != insn)
+ {
+ /* try_split returns the NOTE that INSN became. */
+ first = NEXT_INSN (first);
+ update_flow_info (notes, first, last, insn);
+
+ PUT_CODE (insn, NOTE);
+ NOTE_SOURCE_FILE (insn) = 0;
+ NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
+ if (insn == BLOCK_HEAD (b))
+ BLOCK_HEAD (b) = first;
+ if (insn == BLOCK_END (b))
+ {
+ BLOCK_END (b) = last;
+ break;
+ }
+ }
+ }
+
+ if (insn == BLOCK_END (b))
+ break;
+ }
+}
#include "output.h"
#include "obstack.h"
#include "insn-attr.h"
+#include "resource.h"
#ifdef DELAY_SLOTS
((rtx *) obstack_next_free (&unfilled_slots_obstack))
/* This structure is used to indicate which hardware resources are set or
- needed by insns so far. */
-
-struct resources
-{
- char memory; /* Insn sets or needs a memory location. */
- char unch_memory; /* Insn sets of needs a "unchanging" MEM. */
- char volatil; /* Insn sets or needs a volatile memory loc. */
- char cc; /* Insn sets or needs the condition codes. */
- HARD_REG_SET regs; /* Which registers are set or needed. */
-};
-
-/* Macro to clear all resources. */
-#define CLEAR_RESOURCE(RES) \
- do { (RES)->memory = (RES)->unch_memory = (RES)->volatil = (RES)->cc = 0; \
- CLEAR_HARD_REG_SET ((RES)->regs); } while (0)
-
-/* Indicates what resources are required at the beginning of the epilogue. */
-static struct resources start_of_epilogue_needs;
-
-/* Indicates what resources are required at function end. */
-static struct resources end_of_function_needs;
/* Points to the label before the end of the function. */
static rtx end_of_function_label;
-/* This structure is used to record liveness information at the targets or
- fallthrough insns of branches. We will most likely need the information
- at targets again, so save them in a hash table rather than recomputing them
- each time. */
-
-struct target_info
-{
- int uid; /* INSN_UID of target. */
- struct target_info *next; /* Next info for same hash bucket. */
- HARD_REG_SET live_regs; /* Registers live at target. */
- int block; /* Basic block number containing target. */
- int bb_tick; /* Generation count of basic block info. */
-};
-
-#define TARGET_HASH_PRIME 257
-
-/* Define the hash table itself. */
-static struct target_info **target_hash_table;
-
-/* For each basic block, we maintain a generation number of its basic
- block info, which is updated each time we move an insn from the
- target of a jump. This is the generation number indexed by block
- number. */
-
-static int *bb_ticks;
-
/* Mapping between INSN_UID's and position in the code since INSN_UID's do
not always monotonically increase. */
static int *uid_to_ruid;
/* Highest valid index in `uid_to_ruid'. */
static int max_uid;
-static void mark_referenced_resources PROTO((rtx, struct resources *, int));
-static void mark_set_resources PROTO((rtx, struct resources *,
- int, int));
static int stop_search_p PROTO((rtx, int));
static int resource_conflicts_p PROTO((struct resources *,
struct resources *));
static int mostly_true_jump PROTO((rtx, rtx));
static rtx get_branch_condition PROTO((rtx, rtx));
static int condition_dominates_p PROTO((rtx, rtx));
+static int redirect_with_delay_slots_safe_p PROTO ((rtx, rtx, rtx));
+static int redirect_with_delay_list_safe_p PROTO ((rtx, rtx, rtx));
+static int check_annul_list_true_false PROTO ((int, rtx));
static rtx steal_delay_list_from_target PROTO((rtx, rtx, rtx, rtx,
struct resources *,
struct resources *,
struct resources *,
struct resources *,
int, int *, int *));
-static rtx find_dead_or_set_registers PROTO ((rtx, struct resources *, rtx *,
- int, struct resources,
- struct resources));
static void try_merge_delay_insns PROTO((rtx, rtx));
static rtx redundant_insn PROTO((rtx, rtx, rtx));
static int own_thread_p PROTO((rtx, rtx, int));
-static int find_basic_block PROTO((rtx));
static void update_block PROTO((rtx, rtx));
static int reorg_redirect_jump PROTO((rtx, rtx));
static void update_reg_dead_notes PROTO((rtx, rtx));
static void fix_reg_dead_note PROTO((rtx, rtx));
static void update_reg_unused_notes PROTO((rtx, rtx));
-static void update_live_status PROTO((rtx, rtx));
-static rtx next_insn_no_annul PROTO((rtx));
-static void mark_target_live_regs PROTO((rtx, struct resources *));
static void fill_simple_delay_slots PROTO((int));
static rtx fill_slots_from_thread PROTO((rtx, rtx, rtx, rtx, int, int,
int, int, int *, rtx));
static void fill_eager_delay_slots PROTO((void));
static void relax_delay_slots PROTO((rtx));
static void make_return_insns PROTO((rtx));
-static int redirect_with_delay_slots_safe_p PROTO ((rtx, rtx, rtx));
-static int redirect_with_delay_list_safe_p PROTO ((rtx, rtx, rtx));
-static int check_annul_list_true_false PROTO ((int, rtx));
-\f
-/* Given X, some rtl, and RES, a pointer to a `struct resource', mark
- which resources are references by the insn. If INCLUDE_DELAYED_EFFECTS
- is TRUE, resources used by the called routine will be included for
- CALL_INSNs. */
-
-static void
-mark_referenced_resources (x, res, include_delayed_effects)
- register rtx x;
- register struct resources *res;
- register int include_delayed_effects;
-{
- register enum rtx_code code = GET_CODE (x);
- register int i, j;
- register char *format_ptr;
-
- /* Handle leaf items for which we set resource flags. Also, special-case
- CALL, SET and CLOBBER operators. */
- switch (code)
- {
- case CONST:
- case CONST_INT:
- case CONST_DOUBLE:
- case PC:
- case SYMBOL_REF:
- case LABEL_REF:
- return;
-
- case SUBREG:
- if (GET_CODE (SUBREG_REG (x)) != REG)
- mark_referenced_resources (SUBREG_REG (x), res, 0);
- else
- {
- int regno = REGNO (SUBREG_REG (x)) + SUBREG_WORD (x);
- int last_regno = regno + HARD_REGNO_NREGS (regno, GET_MODE (x));
- for (i = regno; i < last_regno; i++)
- SET_HARD_REG_BIT (res->regs, i);
- }
- return;
-
- case REG:
- for (i = 0; i < HARD_REGNO_NREGS (REGNO (x), GET_MODE (x)); i++)
- SET_HARD_REG_BIT (res->regs, REGNO (x) + i);
- return;
-
- case MEM:
- /* If this memory shouldn't change, it really isn't referencing
- memory. */
- if (RTX_UNCHANGING_P (x))
- res->unch_memory = 1;
- else
- res->memory = 1;
- res->volatil = MEM_VOLATILE_P (x);
-
- /* Mark registers used to access memory. */
- mark_referenced_resources (XEXP (x, 0), res, 0);
- return;
-
- case CC0:
- res->cc = 1;
- return;
-
- case UNSPEC_VOLATILE:
- case ASM_INPUT:
- /* Traditional asm's are always volatile. */
- res->volatil = 1;
- return;
-
- case TRAP_IF:
- res->volatil = 1;
- break;
-
- case ASM_OPERANDS:
- res->volatil = MEM_VOLATILE_P (x);
-
- /* For all ASM_OPERANDS, we must traverse the vector of input operands.
- We can not just fall through here since then we would be confused
- by the ASM_INPUT rtx inside ASM_OPERANDS, which do not indicate
- traditional asms unlike their normal usage. */
-
- for (i = 0; i < ASM_OPERANDS_INPUT_LENGTH (x); i++)
- mark_referenced_resources (ASM_OPERANDS_INPUT (x, i), res, 0);
- return;
-
- case CALL:
- /* The first operand will be a (MEM (xxx)) but doesn't really reference
- memory. The second operand may be referenced, though. */
- mark_referenced_resources (XEXP (XEXP (x, 0), 0), res, 0);
- mark_referenced_resources (XEXP (x, 1), res, 0);
- return;
-
- case SET:
- /* Usually, the first operand of SET is set, not referenced. But
- registers used to access memory are referenced. SET_DEST is
- also referenced if it is a ZERO_EXTRACT or SIGN_EXTRACT. */
-
- mark_referenced_resources (SET_SRC (x), res, 0);
-
- x = SET_DEST (x);
- if (GET_CODE (x) == SIGN_EXTRACT || GET_CODE (x) == ZERO_EXTRACT)
- mark_referenced_resources (x, res, 0);
- else if (GET_CODE (x) == SUBREG)
- x = SUBREG_REG (x);
- if (GET_CODE (x) == MEM)
- mark_referenced_resources (XEXP (x, 0), res, 0);
- return;
-
- case CLOBBER:
- return;
-
- case CALL_INSN:
- if (include_delayed_effects)
- {
- /* A CALL references memory, the frame pointer if it exists, the
- stack pointer, any global registers and any registers given in
- USE insns immediately in front of the CALL.
-
- However, we may have moved some of the parameter loading insns
- into the delay slot of this CALL. If so, the USE's for them
- don't count and should be skipped. */
- rtx insn = PREV_INSN (x);
- rtx sequence = 0;
- int seq_size = 0;
- rtx next = NEXT_INSN (x);
- int i;
-
- /* If we are part of a delay slot sequence, point at the SEQUENCE. */
- if (NEXT_INSN (insn) != x)
- {
- next = NEXT_INSN (NEXT_INSN (insn));
- sequence = PATTERN (NEXT_INSN (insn));
- seq_size = XVECLEN (sequence, 0);
- if (GET_CODE (sequence) != SEQUENCE)
- abort ();
- }
-
- res->memory = 1;
- SET_HARD_REG_BIT (res->regs, STACK_POINTER_REGNUM);
- if (frame_pointer_needed)
- {
- SET_HARD_REG_BIT (res->regs, FRAME_POINTER_REGNUM);
-#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
- SET_HARD_REG_BIT (res->regs, HARD_FRAME_POINTER_REGNUM);
-#endif
- }
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (global_regs[i])
- SET_HARD_REG_BIT (res->regs, i);
-
- /* Check for a NOTE_INSN_SETJMP. If it exists, then we must
- assume that this call can need any register.
-
- This is done to be more conservative about how we handle setjmp.
- We assume that they both use and set all registers. Using all
- registers ensures that a register will not be considered dead
- just because it crosses a setjmp call. A register should be
- considered dead only if the setjmp call returns non-zero. */
- if (next && GET_CODE (next) == NOTE
- && NOTE_LINE_NUMBER (next) == NOTE_INSN_SETJMP)
- SET_HARD_REG_SET (res->regs);
-
- {
- rtx link;
-
- for (link = CALL_INSN_FUNCTION_USAGE (x);
- link;
- link = XEXP (link, 1))
- if (GET_CODE (XEXP (link, 0)) == USE)
- {
- for (i = 1; i < seq_size; i++)
- {
- rtx slot_pat = PATTERN (XVECEXP (sequence, 0, i));
- if (GET_CODE (slot_pat) == SET
- && rtx_equal_p (SET_DEST (slot_pat),
- SET_DEST (XEXP (link, 0))))
- break;
- }
- if (i >= seq_size)
- mark_referenced_resources (SET_DEST (XEXP (link, 0)),
- res, 0);
- }
- }
- }
-
- /* ... fall through to other INSN processing ... */
-
- case INSN:
- case JUMP_INSN:
-
-#ifdef INSN_REFERENCES_ARE_DELAYED
- if (! include_delayed_effects
- && INSN_REFERENCES_ARE_DELAYED (x))
- return;
-#endif
-
- /* No special processing, just speed up. */
- mark_referenced_resources (PATTERN (x), res, include_delayed_effects);
- return;
-
- default:
- break;
- }
-
- /* Process each sub-expression and flag what it needs. */
- format_ptr = GET_RTX_FORMAT (code);
- for (i = 0; i < GET_RTX_LENGTH (code); i++)
- switch (*format_ptr++)
- {
- case 'e':
- mark_referenced_resources (XEXP (x, i), res, include_delayed_effects);
- break;
-
- case 'E':
- for (j = 0; j < XVECLEN (x, i); j++)
- mark_referenced_resources (XVECEXP (x, i, j), res,
- include_delayed_effects);
- break;
- }
-}
-\f
-/* Given X, a part of an insn, and a pointer to a `struct resource',
- RES, indicate which resources are modified by the insn. If
- INCLUDE_DELAYED_EFFECTS is nonzero, also mark resources potentially
- set by the called routine.
-
- If IN_DEST is nonzero, it means we are inside a SET. Otherwise,
- objects are being referenced instead of set.
-
- We never mark the insn as modifying the condition code unless it explicitly
- SETs CC0 even though this is not totally correct. The reason for this is
- that we require a SET of CC0 to immediately precede the reference to CC0.
- So if some other insn sets CC0 as a side-effect, we know it cannot affect
- our computation and thus may be placed in a delay slot. */
-
-static void
-mark_set_resources (x, res, in_dest, include_delayed_effects)
- register rtx x;
- register struct resources *res;
- int in_dest;
- int include_delayed_effects;
-{
- register enum rtx_code code;
- register int i, j;
- register char *format_ptr;
-
- restart:
-
- code = GET_CODE (x);
-
- switch (code)
- {
- case NOTE:
- case BARRIER:
- case CODE_LABEL:
- case USE:
- case CONST_INT:
- case CONST_DOUBLE:
- case LABEL_REF:
- case SYMBOL_REF:
- case CONST:
- case PC:
- /* These don't set any resources. */
- return;
-
- case CC0:
- if (in_dest)
- res->cc = 1;
- return;
-
- case CALL_INSN:
- /* Called routine modifies the condition code, memory, any registers
- that aren't saved across calls, global registers and anything
- explicitly CLOBBERed immediately after the CALL_INSN. */
-
- if (include_delayed_effects)
- {
- rtx next = NEXT_INSN (x);
- rtx prev = PREV_INSN (x);
- rtx link;
-
- res->cc = res->memory = 1;
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (call_used_regs[i] || global_regs[i])
- SET_HARD_REG_BIT (res->regs, i);
-
- /* If X is part of a delay slot sequence, then NEXT should be
- the first insn after the sequence. */
- if (NEXT_INSN (prev) != x)
- next = NEXT_INSN (NEXT_INSN (prev));
-
- for (link = CALL_INSN_FUNCTION_USAGE (x);
- link; link = XEXP (link, 1))
- if (GET_CODE (XEXP (link, 0)) == CLOBBER)
- mark_set_resources (SET_DEST (XEXP (link, 0)), res, 1, 0);
-
- /* Check for a NOTE_INSN_SETJMP. If it exists, then we must
- assume that this call can clobber any register. */
- if (next && GET_CODE (next) == NOTE
- && NOTE_LINE_NUMBER (next) == NOTE_INSN_SETJMP)
- SET_HARD_REG_SET (res->regs);
- }
-
- /* ... and also what its RTL says it modifies, if anything. */
-
- case JUMP_INSN:
- case INSN:
-
- /* An insn consisting of just a CLOBBER (or USE) is just for flow
- and doesn't actually do anything, so we ignore it. */
-
-#ifdef INSN_SETS_ARE_DELAYED
- if (! include_delayed_effects
- && INSN_SETS_ARE_DELAYED (x))
- return;
-#endif
-
- x = PATTERN (x);
- if (GET_CODE (x) != USE && GET_CODE (x) != CLOBBER)
- goto restart;
- return;
-
- case SET:
- /* If the source of a SET is a CALL, this is actually done by
- the called routine. So only include it if we are to include the
- effects of the calling routine. */
-
- mark_set_resources (SET_DEST (x), res,
- (include_delayed_effects
- || GET_CODE (SET_SRC (x)) != CALL),
- 0);
-
- mark_set_resources (SET_SRC (x), res, 0, 0);
- return;
-
- case CLOBBER:
- mark_set_resources (XEXP (x, 0), res, 1, 0);
- return;
-
- case SEQUENCE:
- for (i = 0; i < XVECLEN (x, 0); i++)
- if (! (INSN_ANNULLED_BRANCH_P (XVECEXP (x, 0, 0))
- && INSN_FROM_TARGET_P (XVECEXP (x, 0, i))))
- mark_set_resources (XVECEXP (x, 0, i), res, 0,
- include_delayed_effects);
- return;
-
- case POST_INC:
- case PRE_INC:
- case POST_DEC:
- case PRE_DEC:
- mark_set_resources (XEXP (x, 0), res, 1, 0);
- return;
-
- case ZERO_EXTRACT:
- mark_set_resources (XEXP (x, 0), res, in_dest, 0);
- mark_set_resources (XEXP (x, 1), res, 0, 0);
- mark_set_resources (XEXP (x, 2), res, 0, 0);
- return;
-
- case MEM:
- if (in_dest)
- {
- res->memory = 1;
- res->unch_memory = RTX_UNCHANGING_P (x);
- res->volatil = MEM_VOLATILE_P (x);
- }
-
- mark_set_resources (XEXP (x, 0), res, 0, 0);
- return;
-
- case SUBREG:
- if (in_dest)
- {
- if (GET_CODE (SUBREG_REG (x)) != REG)
- mark_set_resources (SUBREG_REG (x), res,
- in_dest, include_delayed_effects);
- else
- {
- int regno = REGNO (SUBREG_REG (x)) + SUBREG_WORD (x);
- int last_regno = regno + HARD_REGNO_NREGS (regno, GET_MODE (x));
- for (i = regno; i < last_regno; i++)
- SET_HARD_REG_BIT (res->regs, i);
- }
- }
- return;
-
- case REG:
- if (in_dest)
- for (i = 0; i < HARD_REGNO_NREGS (REGNO (x), GET_MODE (x)); i++)
- SET_HARD_REG_BIT (res->regs, REGNO (x) + i);
- return;
-
- default:
- break;
- }
-
- /* Process each sub-expression and flag what it needs. */
- format_ptr = GET_RTX_FORMAT (code);
- for (i = 0; i < GET_RTX_LENGTH (code); i++)
- switch (*format_ptr++)
- {
- case 'e':
- mark_set_resources (XEXP (x, i), res, in_dest, include_delayed_effects);
- break;
-
- case 'E':
- for (j = 0; j < XVECLEN (x, i); j++)
- mark_set_resources (XVECEXP (x, i, j), res, in_dest,
- include_delayed_effects);
- break;
- }
-}
\f
/* Return TRUE if this insn should stop the search for insn to fill delay
slots. LABELS_P indicates that labels should terminate the search.
if (delay_list == 0)
{
- struct target_info *tinfo;
-
- for (tinfo = target_hash_table[INSN_UID (insn) % TARGET_HASH_PRIME];
- tinfo; tinfo = tinfo->next)
- if (tinfo->uid == INSN_UID (insn))
- break;
-
- if (tinfo)
- tinfo->block = -1;
-
+ clear_hashed_info_for_insn (insn);
return gen_rtx_INSN_LIST (VOIDmode, insn, NULL_RTX);
}
return 1;
}
\f
-/* Find the number of the basic block that starts closest to INSN. Return -1
- if we couldn't find such a basic block. */
-
-static int
-find_basic_block (insn)
- rtx insn;
-{
- int i;
-
- /* Scan backwards to the previous BARRIER. Then see if we can find a
- label that starts a basic block. Return the basic block number. */
-
- for (insn = prev_nonnote_insn (insn);
- insn && GET_CODE (insn) != BARRIER;
- insn = prev_nonnote_insn (insn))
- ;
-
- /* The start of the function is basic block zero. */
- if (insn == 0)
- return 0;
-
- /* See if any of the upcoming CODE_LABELs start a basic block. If we reach
- anything other than a CODE_LABEL or note, we can't find this code. */
- for (insn = next_nonnote_insn (insn);
- insn && GET_CODE (insn) == CODE_LABEL;
- insn = next_nonnote_insn (insn))
- {
- for (i = 0; i < n_basic_blocks; i++)
- if (insn == BLOCK_HEAD (i))
- return i;
- }
-
- return -1;
-}
-\f
/* Called when INSN is being moved from a location near the target of a jump.
We leave a marker of the form (use (INSN)) immediately in front
of WHERE for mark_target_live_regs. These markers will be deleted when
rtx insn;
rtx where;
{
- int b;
-
/* Ignore if this was in a delay slot and it came from the target of
a branch. */
if (INSN_FROM_TARGET_P (insn))
/* INSN might be making a value live in a block where it didn't use to
be. So recompute liveness information for this block. */
- b = find_basic_block (insn);
- if (b != -1)
- bb_ticks[b]++;
+ incr_ticks_for_insn (insn);
}
/* Similar to REDIRECT_JUMP except that we update the BB_TICKS entry for
rtx jump;
rtx nlabel;
{
- int b = find_basic_block (jump);
-
- if (b != -1)
- bb_ticks[b]++;
-
+ incr_ticks_for_insn (jump);
return redirect_jump (jump, nlabel);
}
}
}
\f
-/* Marks registers possibly live at the current place being scanned by
- mark_target_live_regs. Used only by next two function. */
-
-static HARD_REG_SET current_live_regs;
-
-/* Marks registers for which we have seen a REG_DEAD note but no assignment.
- Also only used by the next two functions. */
-
-static HARD_REG_SET pending_dead_regs;
-
-/* Utility function called from mark_target_live_regs via note_stores.
- It deadens any CLOBBERed registers and livens any SET registers. */
-
-static void
-update_live_status (dest, x)
- rtx dest;
- rtx x;
-{
- int first_regno, last_regno;
- int i;
-
- if (GET_CODE (dest) != REG
- && (GET_CODE (dest) != SUBREG || GET_CODE (SUBREG_REG (dest)) != REG))
- return;
-
- if (GET_CODE (dest) == SUBREG)
- first_regno = REGNO (SUBREG_REG (dest)) + SUBREG_WORD (dest);
- else
- first_regno = REGNO (dest);
-
- last_regno = first_regno + HARD_REGNO_NREGS (first_regno, GET_MODE (dest));
-
- if (GET_CODE (x) == CLOBBER)
- for (i = first_regno; i < last_regno; i++)
- CLEAR_HARD_REG_BIT (current_live_regs, i);
- else
- for (i = first_regno; i < last_regno; i++)
- {
- SET_HARD_REG_BIT (current_live_regs, i);
- CLEAR_HARD_REG_BIT (pending_dead_regs, i);
- }
-}
-
-/* Similar to next_insn, but ignores insns in the delay slots of
- an annulled branch. */
-
-static rtx
-next_insn_no_annul (insn)
- rtx insn;
-{
- if (insn)
- {
- /* If INSN is an annulled branch, skip any insns from the target
- of the branch. */
- if (INSN_ANNULLED_BRANCH_P (insn)
- && NEXT_INSN (PREV_INSN (insn)) != insn)
- while (INSN_FROM_TARGET_P (NEXT_INSN (insn)))
- insn = NEXT_INSN (insn);
-
- insn = NEXT_INSN (insn);
- if (insn && GET_CODE (insn) == INSN
- && GET_CODE (PATTERN (insn)) == SEQUENCE)
- insn = XVECEXP (PATTERN (insn), 0, 0);
- }
-
- return insn;
-}
-\f
-/* A subroutine of mark_target_live_regs. Search forward from TARGET
- looking for registers that are set before they are used. These are dead.
- Stop after passing a few conditional jumps, and/or a small
- number of unconditional branches. */
-
-static rtx
-find_dead_or_set_registers (target, res, jump_target, jump_count, set, needed)
- rtx target;
- struct resources *res;
- rtx *jump_target;
- int jump_count;
- struct resources set, needed;
-{
- HARD_REG_SET scratch;
- rtx insn, next;
- rtx jump_insn = 0;
- int i;
-
- for (insn = target; insn; insn = next)
- {
- rtx this_jump_insn = insn;
-
- next = NEXT_INSN (insn);
- switch (GET_CODE (insn))
- {
- case CODE_LABEL:
- /* After a label, any pending dead registers that weren't yet
- used can be made dead. */
- AND_COMPL_HARD_REG_SET (pending_dead_regs, needed.regs);
- AND_COMPL_HARD_REG_SET (res->regs, pending_dead_regs);
- CLEAR_HARD_REG_SET (pending_dead_regs);
-
- continue;
-
- case BARRIER:
- case NOTE:
- continue;
-
- case INSN:
- if (GET_CODE (PATTERN (insn)) == USE)
- {
- /* If INSN is a USE made by update_block, we care about the
- underlying insn. Any registers set by the underlying insn
- are live since the insn is being done somewhere else. */
- if (GET_RTX_CLASS (GET_CODE (XEXP (PATTERN (insn), 0))) == 'i')
- mark_set_resources (XEXP (PATTERN (insn), 0), res, 0, 1);
-
- /* All other USE insns are to be ignored. */
- continue;
- }
- else if (GET_CODE (PATTERN (insn)) == CLOBBER)
- continue;
- else if (GET_CODE (PATTERN (insn)) == SEQUENCE)
- {
- /* An unconditional jump can be used to fill the delay slot
- of a call, so search for a JUMP_INSN in any position. */
- for (i = 0; i < XVECLEN (PATTERN (insn), 0); i++)
- {
- this_jump_insn = XVECEXP (PATTERN (insn), 0, i);
- if (GET_CODE (this_jump_insn) == JUMP_INSN)
- break;
- }
- }
-
- default:
- break;
- }
-
- if (GET_CODE (this_jump_insn) == JUMP_INSN)
- {
- if (jump_count++ < 10)
- {
- if (simplejump_p (this_jump_insn)
- || GET_CODE (PATTERN (this_jump_insn)) == RETURN)
- {
- next = JUMP_LABEL (this_jump_insn);
- if (jump_insn == 0)
- {
- jump_insn = insn;
- if (jump_target)
- *jump_target = JUMP_LABEL (this_jump_insn);
- }
- }
- else if (condjump_p (this_jump_insn)
- || condjump_in_parallel_p (this_jump_insn))
- {
- struct resources target_set, target_res;
- struct resources fallthrough_res;
-
- /* We can handle conditional branches here by following
- both paths, and then IOR the results of the two paths
- together, which will give us registers that are dead
- on both paths. Since this is expensive, we give it
- a much higher cost than unconditional branches. The
- cost was chosen so that we will follow at most 1
- conditional branch. */
-
- jump_count += 4;
- if (jump_count >= 10)
- break;
-
- mark_referenced_resources (insn, &needed, 1);
-
- /* For an annulled branch, mark_set_resources ignores slots
- filled by instructions from the target. This is correct
- if the branch is not taken. Since we are following both
- paths from the branch, we must also compute correct info
- if the branch is taken. We do this by inverting all of
- the INSN_FROM_TARGET_P bits, calling mark_set_resources,
- and then inverting the INSN_FROM_TARGET_P bits again. */
-
- if (GET_CODE (PATTERN (insn)) == SEQUENCE
- && INSN_ANNULLED_BRANCH_P (this_jump_insn))
- {
- for (i = 1; i < XVECLEN (PATTERN (insn), 0); i++)
- INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i))
- = ! INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i));
-
- target_set = set;
- mark_set_resources (insn, &target_set, 0, 1);
-
- for (i = 1; i < XVECLEN (PATTERN (insn), 0); i++)
- INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i))
- = ! INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i));
-
- mark_set_resources (insn, &set, 0, 1);
- }
- else
- {
- mark_set_resources (insn, &set, 0, 1);
- target_set = set;
- }
-
- target_res = *res;
- COPY_HARD_REG_SET (scratch, target_set.regs);
- AND_COMPL_HARD_REG_SET (scratch, needed.regs);
- AND_COMPL_HARD_REG_SET (target_res.regs, scratch);
-
- fallthrough_res = *res;
- COPY_HARD_REG_SET (scratch, set.regs);
- AND_COMPL_HARD_REG_SET (scratch, needed.regs);
- AND_COMPL_HARD_REG_SET (fallthrough_res.regs, scratch);
-
- find_dead_or_set_registers (JUMP_LABEL (this_jump_insn),
- &target_res, 0, jump_count,
- target_set, needed);
- find_dead_or_set_registers (next,
- &fallthrough_res, 0, jump_count,
- set, needed);
- IOR_HARD_REG_SET (fallthrough_res.regs, target_res.regs);
- AND_HARD_REG_SET (res->regs, fallthrough_res.regs);
- break;
- }
- else
- break;
- }
- else
- {
- /* Don't try this optimization if we expired our jump count
- above, since that would mean there may be an infinite loop
- in the function being compiled. */
- jump_insn = 0;
- break;
- }
- }
-
- mark_referenced_resources (insn, &needed, 1);
- mark_set_resources (insn, &set, 0, 1);
-
- COPY_HARD_REG_SET (scratch, set.regs);
- AND_COMPL_HARD_REG_SET (scratch, needed.regs);
- AND_COMPL_HARD_REG_SET (res->regs, scratch);
- }
-
- return jump_insn;
-}
-
-/* Set the resources that are live at TARGET.
-
- If TARGET is zero, we refer to the end of the current function and can
- return our precomputed value.
-
- Otherwise, we try to find out what is live by consulting the basic block
- information. This is tricky, because we must consider the actions of
- reload and jump optimization, which occur after the basic block information
- has been computed.
-
- Accordingly, we proceed as follows::
-
- We find the previous BARRIER and look at all immediately following labels
- (with no intervening active insns) to see if any of them start a basic
- block. If we hit the start of the function first, we use block 0.
-
- Once we have found a basic block and a corresponding first insns, we can
- accurately compute the live status from basic_block_live_regs and
- reg_renumber. (By starting at a label following a BARRIER, we are immune
- to actions taken by reload and jump.) Then we scan all insns between
- that point and our target. For each CLOBBER (or for call-clobbered regs
- when we pass a CALL_INSN), mark the appropriate registers are dead. For
- a SET, mark them as live.
-
- We have to be careful when using REG_DEAD notes because they are not
- updated by such things as find_equiv_reg. So keep track of registers
- marked as dead that haven't been assigned to, and mark them dead at the
- next CODE_LABEL since reload and jump won't propagate values across labels.
-
- If we cannot find the start of a basic block (should be a very rare
- case, if it can happen at all), mark everything as potentially live.
-
- Next, scan forward from TARGET looking for things set or clobbered
- before they are used. These are not live.
-
- Because we can be called many times on the same target, save our results
- in a hash table indexed by INSN_UID. */
-
-static void
-mark_target_live_regs (target, res)
- rtx target;
- struct resources *res;
-{
- int b = -1;
- int i;
- struct target_info *tinfo;
- rtx insn;
- rtx jump_insn = 0;
- rtx jump_target;
- HARD_REG_SET scratch;
- struct resources set, needed;
-
- /* Handle end of function. */
- if (target == 0)
- {
- *res = end_of_function_needs;
- return;
- }
-
- /* We have to assume memory is needed, but the CC isn't. */
- res->memory = 1;
- res->volatil = res->unch_memory = 0;
- res->cc = 0;
-
- /* See if we have computed this value already. */
- for (tinfo = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
- tinfo; tinfo = tinfo->next)
- if (tinfo->uid == INSN_UID (target))
- break;
-
- /* Start by getting the basic block number. If we have saved information,
- we can get it from there unless the insn at the start of the basic block
- has been deleted. */
- if (tinfo && tinfo->block != -1
- && ! INSN_DELETED_P (BLOCK_HEAD (tinfo->block)))
- b = tinfo->block;
-
- if (b == -1)
- b = find_basic_block (target);
-
- if (tinfo)
- {
- /* If the information is up-to-date, use it. Otherwise, we will
- update it below. */
- if (b == tinfo->block && b != -1 && tinfo->bb_tick == bb_ticks[b])
- {
- COPY_HARD_REG_SET (res->regs, tinfo->live_regs);
- return;
- }
- }
- else
- {
- /* Allocate a place to put our results and chain it into the
- hash table. */
- tinfo = (struct target_info *) oballoc (sizeof (struct target_info));
- tinfo->uid = INSN_UID (target);
- tinfo->block = b;
- tinfo->next = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
- target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME] = tinfo;
- }
-
- CLEAR_HARD_REG_SET (pending_dead_regs);
-
- /* If we found a basic block, get the live registers from it and update
- them with anything set or killed between its start and the insn before
- TARGET. Otherwise, we must assume everything is live. */
- if (b != -1)
- {
- regset regs_live = basic_block_live_at_start[b];
- int j;
- int regno;
- rtx start_insn, stop_insn;
-
- /* Compute hard regs live at start of block -- this is the real hard regs
- marked live, plus live pseudo regs that have been renumbered to
- hard regs. */
-
- REG_SET_TO_HARD_REG_SET (current_live_regs, regs_live);
-
- EXECUTE_IF_SET_IN_REG_SET
- (regs_live, FIRST_PSEUDO_REGISTER, i,
- {
- if ((regno = reg_renumber[i]) >= 0)
- for (j = regno;
- j < regno + HARD_REGNO_NREGS (regno,
- PSEUDO_REGNO_MODE (i));
- j++)
- SET_HARD_REG_BIT (current_live_regs, j);
- });
-
- /* Get starting and ending insn, handling the case where each might
- be a SEQUENCE. */
- start_insn = (b == 0 ? get_insns () : BLOCK_HEAD (b));
- stop_insn = target;
-
- if (GET_CODE (start_insn) == INSN
- && GET_CODE (PATTERN (start_insn)) == SEQUENCE)
- start_insn = XVECEXP (PATTERN (start_insn), 0, 0);
-
- if (GET_CODE (stop_insn) == INSN
- && GET_CODE (PATTERN (stop_insn)) == SEQUENCE)
- stop_insn = next_insn (PREV_INSN (stop_insn));
-
- for (insn = start_insn; insn != stop_insn;
- insn = next_insn_no_annul (insn))
- {
- rtx link;
- rtx real_insn = insn;
-
- /* If this insn is from the target of a branch, it isn't going to
- be used in the sequel. If it is used in both cases, this
- test will not be true. */
- if (INSN_FROM_TARGET_P (insn))
- continue;
-
- /* If this insn is a USE made by update_block, we care about the
- underlying insn. */
- if (GET_CODE (insn) == INSN && GET_CODE (PATTERN (insn)) == USE
- && GET_RTX_CLASS (GET_CODE (XEXP (PATTERN (insn), 0))) == 'i')
- real_insn = XEXP (PATTERN (insn), 0);
-
- if (GET_CODE (real_insn) == CALL_INSN)
- {
- /* CALL clobbers all call-used regs that aren't fixed except
- sp, ap, and fp. Do this before setting the result of the
- call live. */
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (call_used_regs[i]
- && i != STACK_POINTER_REGNUM && i != FRAME_POINTER_REGNUM
- && i != ARG_POINTER_REGNUM
-#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
- && i != HARD_FRAME_POINTER_REGNUM
-#endif
-#if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
- && ! (i == ARG_POINTER_REGNUM && fixed_regs[i])
-#endif
-#ifdef PIC_OFFSET_TABLE_REGNUM
- && ! (i == PIC_OFFSET_TABLE_REGNUM && flag_pic)
-#endif
- )
- CLEAR_HARD_REG_BIT (current_live_regs, i);
-
- /* A CALL_INSN sets any global register live, since it may
- have been modified by the call. */
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (global_regs[i])
- SET_HARD_REG_BIT (current_live_regs, i);
- }
-
- /* Mark anything killed in an insn to be deadened at the next
- label. Ignore USE insns; the only REG_DEAD notes will be for
- parameters. But they might be early. A CALL_INSN will usually
- clobber registers used for parameters. It isn't worth bothering
- with the unlikely case when it won't. */
- if ((GET_CODE (real_insn) == INSN
- && GET_CODE (PATTERN (real_insn)) != USE
- && GET_CODE (PATTERN (real_insn)) != CLOBBER)
- || GET_CODE (real_insn) == JUMP_INSN
- || GET_CODE (real_insn) == CALL_INSN)
- {
- for (link = REG_NOTES (real_insn); link; link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_DEAD
- && GET_CODE (XEXP (link, 0)) == REG
- && REGNO (XEXP (link, 0)) < FIRST_PSEUDO_REGISTER)
- {
- int first_regno = REGNO (XEXP (link, 0));
- int last_regno
- = (first_regno
- + HARD_REGNO_NREGS (first_regno,
- GET_MODE (XEXP (link, 0))));
-
- for (i = first_regno; i < last_regno; i++)
- SET_HARD_REG_BIT (pending_dead_regs, i);
- }
-
- note_stores (PATTERN (real_insn), update_live_status);
-
- /* If any registers were unused after this insn, kill them.
- These notes will always be accurate. */
- for (link = REG_NOTES (real_insn); link; link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_UNUSED
- && GET_CODE (XEXP (link, 0)) == REG
- && REGNO (XEXP (link, 0)) < FIRST_PSEUDO_REGISTER)
- {
- int first_regno = REGNO (XEXP (link, 0));
- int last_regno
- = (first_regno
- + HARD_REGNO_NREGS (first_regno,
- GET_MODE (XEXP (link, 0))));
-
- for (i = first_regno; i < last_regno; i++)
- CLEAR_HARD_REG_BIT (current_live_regs, i);
- }
- }
-
- else if (GET_CODE (real_insn) == CODE_LABEL)
- {
- /* A label clobbers the pending dead registers since neither
- reload nor jump will propagate a value across a label. */
- AND_COMPL_HARD_REG_SET (current_live_regs, pending_dead_regs);
- CLEAR_HARD_REG_SET (pending_dead_regs);
- }
-
- /* The beginning of the epilogue corresponds to the end of the
- RTL chain when there are no epilogue insns. Certain resources
- are implicitly required at that point. */
- else if (GET_CODE (real_insn) == NOTE
- && NOTE_LINE_NUMBER (real_insn) == NOTE_INSN_EPILOGUE_BEG)
- IOR_HARD_REG_SET (current_live_regs, start_of_epilogue_needs.regs);
- }
-
- COPY_HARD_REG_SET (res->regs, current_live_regs);
- tinfo->block = b;
- tinfo->bb_tick = bb_ticks[b];
- }
- else
- /* We didn't find the start of a basic block. Assume everything
- in use. This should happen only extremely rarely. */
- SET_HARD_REG_SET (res->regs);
-
- CLEAR_RESOURCE (&set);
- CLEAR_RESOURCE (&needed);
-
- jump_insn = find_dead_or_set_registers (target, res, &jump_target, 0,
- set, needed);
-
- /* If we hit an unconditional branch, we have another way of finding out
- what is live: we can see what is live at the branch target and include
- anything used but not set before the branch. The only things that are
- live are those that are live using the above test and the test below. */
-
- if (jump_insn)
- {
- struct resources new_resources;
- rtx stop_insn = next_active_insn (jump_insn);
-
- mark_target_live_regs (next_active_insn (jump_target), &new_resources);
- CLEAR_RESOURCE (&set);
- CLEAR_RESOURCE (&needed);
-
- /* Include JUMP_INSN in the needed registers. */
- for (insn = target; insn != stop_insn; insn = next_active_insn (insn))
- {
- mark_referenced_resources (insn, &needed, 1);
-
- COPY_HARD_REG_SET (scratch, needed.regs);
- AND_COMPL_HARD_REG_SET (scratch, set.regs);
- IOR_HARD_REG_SET (new_resources.regs, scratch);
-
- mark_set_resources (insn, &set, 0, 1);
- }
-
- AND_HARD_REG_SET (res->regs, new_resources.regs);
- }
-
- COPY_HARD_REG_SET (tinfo->live_regs, res->regs);
-}
-\f
/* Scan a function looking for insns that need a delay slot and find insns to
put into the delay slot.
break;
else if (JUMP_LABEL (trial_delay) != target)
{
- mark_target_live_regs
- (next_active_insn (JUMP_LABEL (trial_delay)),
- &needed_at_jump);
+ rtx ninsn =
+ next_active_insn (JUMP_LABEL (trial_delay));
+
+ mark_target_live_regs (get_insns (), ninsn,
+ &needed_at_jump);
needed.memory |= needed_at_jump.memory;
needed.unch_memory |= needed_at_jump.unch_memory;
IOR_HARD_REG_SET (needed.regs, needed_at_jump.regs);
current_function_epilogue_delay_list
= gen_rtx_INSN_LIST (VOIDmode, trial,
current_function_epilogue_delay_list);
- mark_referenced_resources (trial, &end_of_function_needs, 1);
+ mark_end_of_function_resources (trial, 1);
update_block (trial, trial);
delete_insn (trial);
if (condition == const_true_rtx)
CLEAR_RESOURCE (&opposite_needed);
else
- mark_target_live_regs (opposite_thread, &opposite_needed);
+ mark_target_live_regs (get_insns (), opposite_thread, &opposite_needed);
/* If the insn at THREAD can be split, do it here to avoid having to
update THREAD and NEW_THREAD if it is done in the loop below. Also
redirect_jump (insn, target);
}
- /* Indicate what resources are required to be valid at the end of the current
- function. The condition code never is and memory always is. If the
- frame pointer is needed, it is and so is the stack pointer unless
- EXIT_IGNORE_STACK is non-zero. If the frame pointer is not needed, the
- stack pointer is. Registers used to return the function value are
- needed. Registers holding global variables are needed. */
-
- end_of_function_needs.cc = 0;
- end_of_function_needs.memory = 1;
- end_of_function_needs.unch_memory = 0;
- CLEAR_HARD_REG_SET (end_of_function_needs.regs);
-
- if (frame_pointer_needed)
- {
- SET_HARD_REG_BIT (end_of_function_needs.regs, FRAME_POINTER_REGNUM);
-#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
- SET_HARD_REG_BIT (end_of_function_needs.regs, HARD_FRAME_POINTER_REGNUM);
-#endif
-#ifdef EXIT_IGNORE_STACK
- if (! EXIT_IGNORE_STACK
- || current_function_sp_is_unchanging)
-#endif
- SET_HARD_REG_BIT (end_of_function_needs.regs, STACK_POINTER_REGNUM);
- }
- else
- SET_HARD_REG_BIT (end_of_function_needs.regs, STACK_POINTER_REGNUM);
-
- if (current_function_return_rtx != 0)
- mark_referenced_resources (current_function_return_rtx,
- &end_of_function_needs, 1);
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (global_regs[i]
-#ifdef EPILOGUE_USES
- || EPILOGUE_USES (i)
-#endif
- )
- SET_HARD_REG_BIT (end_of_function_needs.regs, i);
-
- /* The registers required to be live at the end of the function are
- represented in the flow information as being dead just prior to
- reaching the end of the function. For example, the return of a value
- might be represented by a USE of the return register immediately
- followed by an unconditional jump to the return label where the
- return label is the end of the RTL chain. The end of the RTL chain
- is then taken to mean that the return register is live.
-
- This sequence is no longer maintained when epilogue instructions are
- added to the RTL chain. To reconstruct the original meaning, the
- start of the epilogue (NOTE_INSN_EPILOGUE_BEG) is regarded as the
- point where these registers become live (start_of_epilogue_needs).
- If epilogue instructions are present, the registers set by those
- instructions won't have been processed by flow. Thus, those
- registers are additionally required at the end of the RTL chain
- (end_of_function_needs). */
-
- start_of_epilogue_needs = end_of_function_needs;
-
- while ((epilogue_insn = next_nonnote_insn (epilogue_insn)))
- mark_set_resources (epilogue_insn, &end_of_function_needs, 0, 1);
+ init_resource_info (epilogue_insn);
/* Show we haven't computed an end-of-function label yet. */
end_of_function_label = 0;
- /* Allocate and initialize the tables used by mark_target_live_regs. */
- target_hash_table
- = (struct target_info **) alloca ((TARGET_HASH_PRIME
- * sizeof (struct target_info *)));
- bzero ((char *) target_hash_table,
- TARGET_HASH_PRIME * sizeof (struct target_info *));
-
- bb_ticks = (int *) alloca (n_basic_blocks * sizeof (int));
- bzero ((char *) bb_ticks, n_basic_blocks * sizeof (int));
-
/* Initialize the statistics for this function. */
bzero ((char *) num_insns_needing_delays, sizeof num_insns_needing_delays);
bzero ((char *) num_filled_delays, sizeof num_filled_delays);
GEN_INT (pred_flags),
REG_NOTES (insn));
}
+ free_resource_info ();
}
#endif /* DELAY_SLOTS */
--- /dev/null
+#include "config.h"
+#include "rtl.h"
+#include "hard-reg-set.h"
+#include "system.h"
+#include "basic-block.h"
+#include "regs.h"
+#include "flags.h"
+#include "output.h"
+#include "resource.h"
+
+/* This structure is used to record liveness information at the targets or
+ fallthrough insns of branches. We will most likely need the information
+ at targets again, so save them in a hash table rather than recomputing them
+ each time. */
+
+struct target_info
+{
+ int uid; /* INSN_UID of target. */
+ struct target_info *next; /* Next info for same hash bucket. */
+ HARD_REG_SET live_regs; /* Registers live at target. */
+ int block; /* Basic block number containing target. */
+ int bb_tick; /* Generation count of basic block info. */
+};
+
+#define TARGET_HASH_PRIME 257
+
+/* Indicates what resources are required at the beginning of the epilogue. */
+static struct resources start_of_epilogue_needs;
+
+/* Indicates what resources are required at function end. */
+static struct resources end_of_function_needs;
+
+/* Define the hash table itself. */
+static struct target_info **target_hash_table = NULL;
+
+/* For each basic block, we maintain a generation number of its basic
+ block info, which is updated each time we move an insn from the
+ target of a jump. This is the generation number indexed by block
+ number. */
+
+static int *bb_ticks;
+
+/* Marks registers possibly live at the current place being scanned by
+ mark_target_live_regs. Used only by next two function. */
+
+static HARD_REG_SET current_live_regs;
+
+/* Marks registers for which we have seen a REG_DEAD note but no assignment.
+ Also only used by the next two functions. */
+
+static HARD_REG_SET pending_dead_regs;
+
+/* Utility function called from mark_target_live_regs via note_stores.
+ It deadens any CLOBBERed registers and livens any SET registers. */
+
+static void
+update_live_status (dest, x)
+ rtx dest;
+ rtx x;
+{
+ int first_regno, last_regno;
+ int i;
+
+ if (GET_CODE (dest) != REG
+ && (GET_CODE (dest) != SUBREG || GET_CODE (SUBREG_REG (dest)) != REG))
+ return;
+
+ if (GET_CODE (dest) == SUBREG)
+ first_regno = REGNO (SUBREG_REG (dest)) + SUBREG_WORD (dest);
+ else
+ first_regno = REGNO (dest);
+
+ last_regno = first_regno + HARD_REGNO_NREGS (first_regno, GET_MODE (dest));
+
+ if (GET_CODE (x) == CLOBBER)
+ for (i = first_regno; i < last_regno; i++)
+ CLEAR_HARD_REG_BIT (current_live_regs, i);
+ else
+ for (i = first_regno; i < last_regno; i++)
+ {
+ SET_HARD_REG_BIT (current_live_regs, i);
+ CLEAR_HARD_REG_BIT (pending_dead_regs, i);
+ }
+}
+/* Find the number of the basic block that starts closest to INSN. Return -1
+ if we couldn't find such a basic block. */
+
+static int
+find_basic_block (insn)
+ rtx insn;
+{
+ int i;
+
+ /* Scan backwards to the previous BARRIER. Then see if we can find a
+ label that starts a basic block. Return the basic block number. */
+
+ for (insn = prev_nonnote_insn (insn);
+ insn && GET_CODE (insn) != BARRIER;
+ insn = prev_nonnote_insn (insn))
+ ;
+
+ /* The start of the function is basic block zero. */
+ if (insn == 0)
+ return 0;
+
+ /* See if any of the upcoming CODE_LABELs start a basic block. If we reach
+ anything other than a CODE_LABEL or note, we can't find this code. */
+ for (insn = next_nonnote_insn (insn);
+ insn && GET_CODE (insn) == CODE_LABEL;
+ insn = next_nonnote_insn (insn))
+ {
+ for (i = 0; i < n_basic_blocks; i++)
+ if (insn == BLOCK_HEAD (i))
+ return i;
+ }
+
+ return -1;
+}
+\f
+/* Similar to next_insn, but ignores insns in the delay slots of
+ an annulled branch. */
+
+static rtx
+next_insn_no_annul (insn)
+ rtx insn;
+{
+ if (insn)
+ {
+ /* If INSN is an annulled branch, skip any insns from the target
+ of the branch. */
+ if (INSN_ANNULLED_BRANCH_P (insn)
+ && NEXT_INSN (PREV_INSN (insn)) != insn)
+ while (INSN_FROM_TARGET_P (NEXT_INSN (insn)))
+ insn = NEXT_INSN (insn);
+
+ insn = NEXT_INSN (insn);
+ if (insn && GET_CODE (insn) == INSN
+ && GET_CODE (PATTERN (insn)) == SEQUENCE)
+ insn = XVECEXP (PATTERN (insn), 0, 0);
+ }
+
+ return insn;
+}
+\f
+/* Given X, some rtl, and RES, a pointer to a `struct resource', mark
+ which resources are references by the insn. If INCLUDE_DELAYED_EFFECTS
+ is TRUE, resources used by the called routine will be included for
+ CALL_INSNs. */
+
+void
+mark_referenced_resources (x, res, include_delayed_effects)
+ register rtx x;
+ register struct resources *res;
+ register int include_delayed_effects;
+{
+ register enum rtx_code code = GET_CODE (x);
+ register int i, j;
+ register char *format_ptr;
+
+ /* Handle leaf items for which we set resource flags. Also, special-case
+ CALL, SET and CLOBBER operators. */
+ switch (code)
+ {
+ case CONST:
+ case CONST_INT:
+ case CONST_DOUBLE:
+ case PC:
+ case SYMBOL_REF:
+ case LABEL_REF:
+ return;
+
+ case SUBREG:
+ if (GET_CODE (SUBREG_REG (x)) != REG)
+ mark_referenced_resources (SUBREG_REG (x), res, 0);
+ else
+ {
+ int regno = REGNO (SUBREG_REG (x)) + SUBREG_WORD (x);
+ int last_regno = regno + HARD_REGNO_NREGS (regno, GET_MODE (x));
+ for (i = regno; i < last_regno; i++)
+ SET_HARD_REG_BIT (res->regs, i);
+ }
+ return;
+
+ case REG:
+ for (i = 0; i < HARD_REGNO_NREGS (REGNO (x), GET_MODE (x)); i++)
+ SET_HARD_REG_BIT (res->regs, REGNO (x) + i);
+ return;
+
+ case MEM:
+ /* If this memory shouldn't change, it really isn't referencing
+ memory. */
+ if (RTX_UNCHANGING_P (x))
+ res->unch_memory = 1;
+ else
+ res->memory = 1;
+ res->volatil = MEM_VOLATILE_P (x);
+
+ /* Mark registers used to access memory. */
+ mark_referenced_resources (XEXP (x, 0), res, 0);
+ return;
+
+ case CC0:
+ res->cc = 1;
+ return;
+
+ case UNSPEC_VOLATILE:
+ case ASM_INPUT:
+ /* Traditional asm's are always volatile. */
+ res->volatil = 1;
+ return;
+
+ case TRAP_IF:
+ res->volatil = 1;
+ break;
+
+ case ASM_OPERANDS:
+ res->volatil = MEM_VOLATILE_P (x);
+
+ /* For all ASM_OPERANDS, we must traverse the vector of input operands.
+ We can not just fall through here since then we would be confused
+ by the ASM_INPUT rtx inside ASM_OPERANDS, which do not indicate
+ traditional asms unlike their normal usage. */
+
+ for (i = 0; i < ASM_OPERANDS_INPUT_LENGTH (x); i++)
+ mark_referenced_resources (ASM_OPERANDS_INPUT (x, i), res, 0);
+ return;
+
+ case CALL:
+ /* The first operand will be a (MEM (xxx)) but doesn't really reference
+ memory. The second operand may be referenced, though. */
+ mark_referenced_resources (XEXP (XEXP (x, 0), 0), res, 0);
+ mark_referenced_resources (XEXP (x, 1), res, 0);
+ return;
+
+ case SET:
+ /* Usually, the first operand of SET is set, not referenced. But
+ registers used to access memory are referenced. SET_DEST is
+ also referenced if it is a ZERO_EXTRACT or SIGN_EXTRACT. */
+
+ mark_referenced_resources (SET_SRC (x), res, 0);
+
+ x = SET_DEST (x);
+ if (GET_CODE (x) == SIGN_EXTRACT || GET_CODE (x) == ZERO_EXTRACT)
+ mark_referenced_resources (x, res, 0);
+ else if (GET_CODE (x) == SUBREG)
+ x = SUBREG_REG (x);
+ if (GET_CODE (x) == MEM)
+ mark_referenced_resources (XEXP (x, 0), res, 0);
+ return;
+
+ case CLOBBER:
+ return;
+
+ case CALL_INSN:
+ if (include_delayed_effects)
+ {
+ /* A CALL references memory, the frame pointer if it exists, the
+ stack pointer, any global registers and any registers given in
+ USE insns immediately in front of the CALL.
+
+ However, we may have moved some of the parameter loading insns
+ into the delay slot of this CALL. If so, the USE's for them
+ don't count and should be skipped. */
+ rtx insn = PREV_INSN (x);
+ rtx sequence = 0;
+ int seq_size = 0;
+ rtx next = NEXT_INSN (x);
+ int i;
+
+ /* If we are part of a delay slot sequence, point at the SEQUENCE. */
+ if (NEXT_INSN (insn) != x)
+ {
+ next = NEXT_INSN (NEXT_INSN (insn));
+ sequence = PATTERN (NEXT_INSN (insn));
+ seq_size = XVECLEN (sequence, 0);
+ if (GET_CODE (sequence) != SEQUENCE)
+ abort ();
+ }
+
+ res->memory = 1;
+ SET_HARD_REG_BIT (res->regs, STACK_POINTER_REGNUM);
+ if (frame_pointer_needed)
+ {
+ SET_HARD_REG_BIT (res->regs, FRAME_POINTER_REGNUM);
+#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
+ SET_HARD_REG_BIT (res->regs, HARD_FRAME_POINTER_REGNUM);
+#endif
+ }
+
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (global_regs[i])
+ SET_HARD_REG_BIT (res->regs, i);
+
+ /* Check for a NOTE_INSN_SETJMP. If it exists, then we must
+ assume that this call can need any register.
+
+ This is done to be more conservative about how we handle setjmp.
+ We assume that they both use and set all registers. Using all
+ registers ensures that a register will not be considered dead
+ just because it crosses a setjmp call. A register should be
+ considered dead only if the setjmp call returns non-zero. */
+ if (next && GET_CODE (next) == NOTE
+ && NOTE_LINE_NUMBER (next) == NOTE_INSN_SETJMP)
+ SET_HARD_REG_SET (res->regs);
+
+ {
+ rtx link;
+
+ for (link = CALL_INSN_FUNCTION_USAGE (x);
+ link;
+ link = XEXP (link, 1))
+ if (GET_CODE (XEXP (link, 0)) == USE)
+ {
+ for (i = 1; i < seq_size; i++)
+ {
+ rtx slot_pat = PATTERN (XVECEXP (sequence, 0, i));
+ if (GET_CODE (slot_pat) == SET
+ && rtx_equal_p (SET_DEST (slot_pat),
+ SET_DEST (XEXP (link, 0))))
+ break;
+ }
+ if (i >= seq_size)
+ mark_referenced_resources (SET_DEST (XEXP (link, 0)),
+ res, 0);
+ }
+ }
+ }
+
+ /* ... fall through to other INSN processing ... */
+
+ case INSN:
+ case JUMP_INSN:
+
+#ifdef INSN_REFERENCES_ARE_DELAYED
+ if (! include_delayed_effects
+ && INSN_REFERENCES_ARE_DELAYED (x))
+ return;
+#endif
+
+ /* No special processing, just speed up. */
+ mark_referenced_resources (PATTERN (x), res, include_delayed_effects);
+ return;
+
+ default:
+ break;
+ }
+
+ /* Process each sub-expression and flag what it needs. */
+ format_ptr = GET_RTX_FORMAT (code);
+ for (i = 0; i < GET_RTX_LENGTH (code); i++)
+ switch (*format_ptr++)
+ {
+ case 'e':
+ mark_referenced_resources (XEXP (x, i), res, include_delayed_effects);
+ break;
+
+ case 'E':
+ for (j = 0; j < XVECLEN (x, i); j++)
+ mark_referenced_resources (XVECEXP (x, i, j), res,
+ include_delayed_effects);
+ break;
+ }
+}
+\f
+/* A subroutine of mark_target_live_regs. Search forward from TARGET
+ looking for registers that are set before they are used. These are dead.
+ Stop after passing a few conditional jumps, and/or a small
+ number of unconditional branches. */
+
+static rtx
+find_dead_or_set_registers (target, res, jump_target, jump_count, set, needed)
+ rtx target;
+ struct resources *res;
+ rtx *jump_target;
+ int jump_count;
+ struct resources set, needed;
+{
+ HARD_REG_SET scratch;
+ rtx insn, next;
+ rtx jump_insn = 0;
+ int i;
+
+ for (insn = target; insn; insn = next)
+ {
+ rtx this_jump_insn = insn;
+
+ next = NEXT_INSN (insn);
+ switch (GET_CODE (insn))
+ {
+ case CODE_LABEL:
+ /* After a label, any pending dead registers that weren't yet
+ used can be made dead. */
+ AND_COMPL_HARD_REG_SET (pending_dead_regs, needed.regs);
+ AND_COMPL_HARD_REG_SET (res->regs, pending_dead_regs);
+ CLEAR_HARD_REG_SET (pending_dead_regs);
+
+ continue;
+
+ case BARRIER:
+ case NOTE:
+ continue;
+
+ case INSN:
+ if (GET_CODE (PATTERN (insn)) == USE)
+ {
+ /* If INSN is a USE made by update_block, we care about the
+ underlying insn. Any registers set by the underlying insn
+ are live since the insn is being done somewhere else. */
+ if (GET_RTX_CLASS (GET_CODE (XEXP (PATTERN (insn), 0))) == 'i')
+ mark_set_resources (XEXP (PATTERN (insn), 0), res, 0, 1);
+
+ /* All other USE insns are to be ignored. */
+ continue;
+ }
+ else if (GET_CODE (PATTERN (insn)) == CLOBBER)
+ continue;
+ else if (GET_CODE (PATTERN (insn)) == SEQUENCE)
+ {
+ /* An unconditional jump can be used to fill the delay slot
+ of a call, so search for a JUMP_INSN in any position. */
+ for (i = 0; i < XVECLEN (PATTERN (insn), 0); i++)
+ {
+ this_jump_insn = XVECEXP (PATTERN (insn), 0, i);
+ if (GET_CODE (this_jump_insn) == JUMP_INSN)
+ break;
+ }
+ }
+
+ default:
+ break;
+ }
+
+ if (GET_CODE (this_jump_insn) == JUMP_INSN)
+ {
+ if (jump_count++ < 10)
+ {
+ if (simplejump_p (this_jump_insn)
+ || GET_CODE (PATTERN (this_jump_insn)) == RETURN)
+ {
+ next = JUMP_LABEL (this_jump_insn);
+ if (jump_insn == 0)
+ {
+ jump_insn = insn;
+ if (jump_target)
+ *jump_target = JUMP_LABEL (this_jump_insn);
+ }
+ }
+ else if (condjump_p (this_jump_insn)
+ || condjump_in_parallel_p (this_jump_insn))
+ {
+ struct resources target_set, target_res;
+ struct resources fallthrough_res;
+
+ /* We can handle conditional branches here by following
+ both paths, and then IOR the results of the two paths
+ together, which will give us registers that are dead
+ on both paths. Since this is expensive, we give it
+ a much higher cost than unconditional branches. The
+ cost was chosen so that we will follow at most 1
+ conditional branch. */
+
+ jump_count += 4;
+ if (jump_count >= 10)
+ break;
+
+ mark_referenced_resources (insn, &needed, 1);
+
+ /* For an annulled branch, mark_set_resources ignores slots
+ filled by instructions from the target. This is correct
+ if the branch is not taken. Since we are following both
+ paths from the branch, we must also compute correct info
+ if the branch is taken. We do this by inverting all of
+ the INSN_FROM_TARGET_P bits, calling mark_set_resources,
+ and then inverting the INSN_FROM_TARGET_P bits again. */
+
+ if (GET_CODE (PATTERN (insn)) == SEQUENCE
+ && INSN_ANNULLED_BRANCH_P (this_jump_insn))
+ {
+ for (i = 1; i < XVECLEN (PATTERN (insn), 0); i++)
+ INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i))
+ = ! INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i));
+
+ target_set = set;
+ mark_set_resources (insn, &target_set, 0, 1);
+
+ for (i = 1; i < XVECLEN (PATTERN (insn), 0); i++)
+ INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i))
+ = ! INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i));
+
+ mark_set_resources (insn, &set, 0, 1);
+ }
+ else
+ {
+ mark_set_resources (insn, &set, 0, 1);
+ target_set = set;
+ }
+
+ target_res = *res;
+ COPY_HARD_REG_SET (scratch, target_set.regs);
+ AND_COMPL_HARD_REG_SET (scratch, needed.regs);
+ AND_COMPL_HARD_REG_SET (target_res.regs, scratch);
+
+ fallthrough_res = *res;
+ COPY_HARD_REG_SET (scratch, set.regs);
+ AND_COMPL_HARD_REG_SET (scratch, needed.regs);
+ AND_COMPL_HARD_REG_SET (fallthrough_res.regs, scratch);
+
+ find_dead_or_set_registers (JUMP_LABEL (this_jump_insn),
+ &target_res, 0, jump_count,
+ target_set, needed);
+ find_dead_or_set_registers (next,
+ &fallthrough_res, 0, jump_count,
+ set, needed);
+ IOR_HARD_REG_SET (fallthrough_res.regs, target_res.regs);
+ AND_HARD_REG_SET (res->regs, fallthrough_res.regs);
+ break;
+ }
+ else
+ break;
+ }
+ else
+ {
+ /* Don't try this optimization if we expired our jump count
+ above, since that would mean there may be an infinite loop
+ in the function being compiled. */
+ jump_insn = 0;
+ break;
+ }
+ }
+
+ mark_referenced_resources (insn, &needed, 1);
+ mark_set_resources (insn, &set, 0, 1);
+
+ COPY_HARD_REG_SET (scratch, set.regs);
+ AND_COMPL_HARD_REG_SET (scratch, needed.regs);
+ AND_COMPL_HARD_REG_SET (res->regs, scratch);
+ }
+
+ return jump_insn;
+}
+\f
+/* Given X, a part of an insn, and a pointer to a `struct resource',
+ RES, indicate which resources are modified by the insn. If
+ INCLUDE_DELAYED_EFFECTS is nonzero, also mark resources potentially
+ set by the called routine.
+
+ If IN_DEST is nonzero, it means we are inside a SET. Otherwise,
+ objects are being referenced instead of set.
+
+ We never mark the insn as modifying the condition code unless it explicitly
+ SETs CC0 even though this is not totally correct. The reason for this is
+ that we require a SET of CC0 to immediately precede the reference to CC0.
+ So if some other insn sets CC0 as a side-effect, we know it cannot affect
+ our computation and thus may be placed in a delay slot. */
+
+void
+mark_set_resources (x, res, in_dest, include_delayed_effects)
+ register rtx x;
+ register struct resources *res;
+ int in_dest;
+ int include_delayed_effects;
+{
+ register enum rtx_code code;
+ register int i, j;
+ register char *format_ptr;
+
+ restart:
+
+ code = GET_CODE (x);
+
+ switch (code)
+ {
+ case NOTE:
+ case BARRIER:
+ case CODE_LABEL:
+ case USE:
+ case CONST_INT:
+ case CONST_DOUBLE:
+ case LABEL_REF:
+ case SYMBOL_REF:
+ case CONST:
+ case PC:
+ /* These don't set any resources. */
+ return;
+
+ case CC0:
+ if (in_dest)
+ res->cc = 1;
+ return;
+
+ case CALL_INSN:
+ /* Called routine modifies the condition code, memory, any registers
+ that aren't saved across calls, global registers and anything
+ explicitly CLOBBERed immediately after the CALL_INSN. */
+
+ if (include_delayed_effects)
+ {
+ rtx next = NEXT_INSN (x);
+ rtx prev = PREV_INSN (x);
+ rtx link;
+
+ res->cc = res->memory = 1;
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (call_used_regs[i] || global_regs[i])
+ SET_HARD_REG_BIT (res->regs, i);
+
+ /* If X is part of a delay slot sequence, then NEXT should be
+ the first insn after the sequence. */
+ if (NEXT_INSN (prev) != x)
+ next = NEXT_INSN (NEXT_INSN (prev));
+
+ for (link = CALL_INSN_FUNCTION_USAGE (x);
+ link; link = XEXP (link, 1))
+ if (GET_CODE (XEXP (link, 0)) == CLOBBER)
+ mark_set_resources (SET_DEST (XEXP (link, 0)), res, 1, 0);
+
+ /* Check for a NOTE_INSN_SETJMP. If it exists, then we must
+ assume that this call can clobber any register. */
+ if (next && GET_CODE (next) == NOTE
+ && NOTE_LINE_NUMBER (next) == NOTE_INSN_SETJMP)
+ SET_HARD_REG_SET (res->regs);
+ }
+
+ /* ... and also what its RTL says it modifies, if anything. */
+
+ case JUMP_INSN:
+ case INSN:
+
+ /* An insn consisting of just a CLOBBER (or USE) is just for flow
+ and doesn't actually do anything, so we ignore it. */
+
+#ifdef INSN_SETS_ARE_DELAYED
+ if (! include_delayed_effects
+ && INSN_SETS_ARE_DELAYED (x))
+ return;
+#endif
+
+ x = PATTERN (x);
+ if (GET_CODE (x) != USE && GET_CODE (x) != CLOBBER)
+ goto restart;
+ return;
+
+ case SET:
+ /* If the source of a SET is a CALL, this is actually done by
+ the called routine. So only include it if we are to include the
+ effects of the calling routine. */
+
+ mark_set_resources (SET_DEST (x), res,
+ (include_delayed_effects
+ || GET_CODE (SET_SRC (x)) != CALL),
+ 0);
+
+ mark_set_resources (SET_SRC (x), res, 0, 0);
+ return;
+
+ case CLOBBER:
+ mark_set_resources (XEXP (x, 0), res, 1, 0);
+ return;
+
+ case SEQUENCE:
+ for (i = 0; i < XVECLEN (x, 0); i++)
+ if (! (INSN_ANNULLED_BRANCH_P (XVECEXP (x, 0, 0))
+ && INSN_FROM_TARGET_P (XVECEXP (x, 0, i))))
+ mark_set_resources (XVECEXP (x, 0, i), res, 0,
+ include_delayed_effects);
+ return;
+
+ case POST_INC:
+ case PRE_INC:
+ case POST_DEC:
+ case PRE_DEC:
+ mark_set_resources (XEXP (x, 0), res, 1, 0);
+ return;
+
+ case ZERO_EXTRACT:
+ mark_set_resources (XEXP (x, 0), res, in_dest, 0);
+ mark_set_resources (XEXP (x, 1), res, 0, 0);
+ mark_set_resources (XEXP (x, 2), res, 0, 0);
+ return;
+
+ case MEM:
+ if (in_dest)
+ {
+ res->memory = 1;
+ res->unch_memory = RTX_UNCHANGING_P (x);
+ res->volatil = MEM_VOLATILE_P (x);
+ }
+
+ mark_set_resources (XEXP (x, 0), res, 0, 0);
+ return;
+
+ case SUBREG:
+ if (in_dest)
+ {
+ if (GET_CODE (SUBREG_REG (x)) != REG)
+ mark_set_resources (SUBREG_REG (x), res,
+ in_dest, include_delayed_effects);
+ else
+ {
+ int regno = REGNO (SUBREG_REG (x)) + SUBREG_WORD (x);
+ int last_regno = regno + HARD_REGNO_NREGS (regno, GET_MODE (x));
+ for (i = regno; i < last_regno; i++)
+ SET_HARD_REG_BIT (res->regs, i);
+ }
+ }
+ return;
+
+ case REG:
+ if (in_dest)
+ for (i = 0; i < HARD_REGNO_NREGS (REGNO (x), GET_MODE (x)); i++)
+ SET_HARD_REG_BIT (res->regs, REGNO (x) + i);
+ return;
+
+ default:
+ break;
+ }
+
+ /* Process each sub-expression and flag what it needs. */
+ format_ptr = GET_RTX_FORMAT (code);
+ for (i = 0; i < GET_RTX_LENGTH (code); i++)
+ switch (*format_ptr++)
+ {
+ case 'e':
+ mark_set_resources (XEXP (x, i), res, in_dest, include_delayed_effects);
+ break;
+
+ case 'E':
+ for (j = 0; j < XVECLEN (x, i); j++)
+ mark_set_resources (XVECEXP (x, i, j), res, in_dest,
+ include_delayed_effects);
+ break;
+ }
+}
+\f
+/* Set the resources that are live at TARGET.
+
+ If TARGET is zero, we refer to the end of the current function and can
+ return our precomputed value.
+
+ Otherwise, we try to find out what is live by consulting the basic block
+ information. This is tricky, because we must consider the actions of
+ reload and jump optimization, which occur after the basic block information
+ has been computed.
+
+ Accordingly, we proceed as follows::
+
+ We find the previous BARRIER and look at all immediately following labels
+ (with no intervening active insns) to see if any of them start a basic
+ block. If we hit the start of the function first, we use block 0.
+
+ Once we have found a basic block and a corresponding first insns, we can
+ accurately compute the live status from basic_block_live_regs and
+ reg_renumber. (By starting at a label following a BARRIER, we are immune
+ to actions taken by reload and jump.) Then we scan all insns between
+ that point and our target. For each CLOBBER (or for call-clobbered regs
+ when we pass a CALL_INSN), mark the appropriate registers are dead. For
+ a SET, mark them as live.
+
+ We have to be careful when using REG_DEAD notes because they are not
+ updated by such things as find_equiv_reg. So keep track of registers
+ marked as dead that haven't been assigned to, and mark them dead at the
+ next CODE_LABEL since reload and jump won't propagate values across labels.
+
+ If we cannot find the start of a basic block (should be a very rare
+ case, if it can happen at all), mark everything as potentially live.
+
+ Next, scan forward from TARGET looking for things set or clobbered
+ before they are used. These are not live.
+
+ Because we can be called many times on the same target, save our results
+ in a hash table indexed by INSN_UID. This is only done if the function
+ init_resource_info () was invoked before we are called. */
+
+void
+mark_target_live_regs (insns, target, res)
+ rtx insns;
+ rtx target;
+ struct resources *res;
+{
+ int b = -1;
+ int i;
+ struct target_info *tinfo = NULL;
+ rtx insn;
+ rtx jump_insn = 0;
+ rtx jump_target;
+ HARD_REG_SET scratch;
+ struct resources set, needed;
+
+ /* Handle end of function. */
+ if (target == 0)
+ {
+ *res = end_of_function_needs;
+ return;
+ }
+
+ /* We have to assume memory is needed, but the CC isn't. */
+ res->memory = 1;
+ res->volatil = res->unch_memory = 0;
+ res->cc = 0;
+
+ /* See if we have computed this value already. */
+ if (target_hash_table != NULL)
+ {
+ for (tinfo = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
+ tinfo; tinfo = tinfo->next)
+ if (tinfo->uid == INSN_UID (target))
+ break;
+
+ /* Start by getting the basic block number. If we have saved
+ information, we can get it from there unless the insn at the
+ start of the basic block has been deleted. */
+ if (tinfo && tinfo->block != -1
+ && ! INSN_DELETED_P (BLOCK_HEAD (tinfo->block)))
+ b = tinfo->block;
+ }
+
+ if (b == -1)
+ b = find_basic_block (target);
+
+ if (target_hash_table != NULL)
+ {
+ if (tinfo)
+ {
+ /* If the information is up-to-date, use it. Otherwise, we will
+ update it below. */
+ if (b == tinfo->block && b != -1 && tinfo->bb_tick == bb_ticks[b])
+ {
+ COPY_HARD_REG_SET (res->regs, tinfo->live_regs);
+ return;
+ }
+ }
+ else
+ {
+ /* Allocate a place to put our results and chain it into the
+ hash table. */
+ tinfo = (struct target_info *) oballoc (sizeof (struct target_info));
+ tinfo->uid = INSN_UID (target);
+ tinfo->block = b;
+ tinfo->next = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
+ target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME] = tinfo;
+ }
+ }
+
+ CLEAR_HARD_REG_SET (pending_dead_regs);
+
+ /* If we found a basic block, get the live registers from it and update
+ them with anything set or killed between its start and the insn before
+ TARGET. Otherwise, we must assume everything is live. */
+ if (b != -1)
+ {
+ regset regs_live = basic_block_live_at_start[b];
+ int j;
+ int regno;
+ rtx start_insn, stop_insn;
+
+ /* Compute hard regs live at start of block -- this is the real hard regs
+ marked live, plus live pseudo regs that have been renumbered to
+ hard regs. */
+
+ REG_SET_TO_HARD_REG_SET (current_live_regs, regs_live);
+
+ EXECUTE_IF_SET_IN_REG_SET
+ (regs_live, FIRST_PSEUDO_REGISTER, i,
+ {
+ if ((regno = reg_renumber[i]) >= 0)
+ for (j = regno;
+ j < regno + HARD_REGNO_NREGS (regno,
+ PSEUDO_REGNO_MODE (i));
+ j++)
+ SET_HARD_REG_BIT (current_live_regs, j);
+ });
+
+ /* Get starting and ending insn, handling the case where each might
+ be a SEQUENCE. */
+ start_insn = (b == 0 ? insns : BLOCK_HEAD (b));
+ stop_insn = target;
+
+ if (GET_CODE (start_insn) == INSN
+ && GET_CODE (PATTERN (start_insn)) == SEQUENCE)
+ start_insn = XVECEXP (PATTERN (start_insn), 0, 0);
+
+ if (GET_CODE (stop_insn) == INSN
+ && GET_CODE (PATTERN (stop_insn)) == SEQUENCE)
+ stop_insn = next_insn (PREV_INSN (stop_insn));
+
+ for (insn = start_insn; insn != stop_insn;
+ insn = next_insn_no_annul (insn))
+ {
+ rtx link;
+ rtx real_insn = insn;
+
+ /* If this insn is from the target of a branch, it isn't going to
+ be used in the sequel. If it is used in both cases, this
+ test will not be true. */
+ if (INSN_FROM_TARGET_P (insn))
+ continue;
+
+ /* If this insn is a USE made by update_block, we care about the
+ underlying insn. */
+ if (GET_CODE (insn) == INSN && GET_CODE (PATTERN (insn)) == USE
+ && GET_RTX_CLASS (GET_CODE (XEXP (PATTERN (insn), 0))) == 'i')
+ real_insn = XEXP (PATTERN (insn), 0);
+
+ if (GET_CODE (real_insn) == CALL_INSN)
+ {
+ /* CALL clobbers all call-used regs that aren't fixed except
+ sp, ap, and fp. Do this before setting the result of the
+ call live. */
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (call_used_regs[i]
+ && i != STACK_POINTER_REGNUM && i != FRAME_POINTER_REGNUM
+ && i != ARG_POINTER_REGNUM
+#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
+ && i != HARD_FRAME_POINTER_REGNUM
+#endif
+#if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
+ && ! (i == ARG_POINTER_REGNUM && fixed_regs[i])
+#endif
+#ifdef PIC_OFFSET_TABLE_REGNUM
+ && ! (i == PIC_OFFSET_TABLE_REGNUM && flag_pic)
+#endif
+ )
+ CLEAR_HARD_REG_BIT (current_live_regs, i);
+
+ /* A CALL_INSN sets any global register live, since it may
+ have been modified by the call. */
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (global_regs[i])
+ SET_HARD_REG_BIT (current_live_regs, i);
+ }
+
+ /* Mark anything killed in an insn to be deadened at the next
+ label. Ignore USE insns; the only REG_DEAD notes will be for
+ parameters. But they might be early. A CALL_INSN will usually
+ clobber registers used for parameters. It isn't worth bothering
+ with the unlikely case when it won't. */
+ if ((GET_CODE (real_insn) == INSN
+ && GET_CODE (PATTERN (real_insn)) != USE
+ && GET_CODE (PATTERN (real_insn)) != CLOBBER)
+ || GET_CODE (real_insn) == JUMP_INSN
+ || GET_CODE (real_insn) == CALL_INSN)
+ {
+ for (link = REG_NOTES (real_insn); link; link = XEXP (link, 1))
+ if (REG_NOTE_KIND (link) == REG_DEAD
+ && GET_CODE (XEXP (link, 0)) == REG
+ && REGNO (XEXP (link, 0)) < FIRST_PSEUDO_REGISTER)
+ {
+ int first_regno = REGNO (XEXP (link, 0));
+ int last_regno
+ = (first_regno
+ + HARD_REGNO_NREGS (first_regno,
+ GET_MODE (XEXP (link, 0))));
+
+ for (i = first_regno; i < last_regno; i++)
+ SET_HARD_REG_BIT (pending_dead_regs, i);
+ }
+
+ note_stores (PATTERN (real_insn), update_live_status);
+
+ /* If any registers were unused after this insn, kill them.
+ These notes will always be accurate. */
+ for (link = REG_NOTES (real_insn); link; link = XEXP (link, 1))
+ if (REG_NOTE_KIND (link) == REG_UNUSED
+ && GET_CODE (XEXP (link, 0)) == REG
+ && REGNO (XEXP (link, 0)) < FIRST_PSEUDO_REGISTER)
+ {
+ int first_regno = REGNO (XEXP (link, 0));
+ int last_regno
+ = (first_regno
+ + HARD_REGNO_NREGS (first_regno,
+ GET_MODE (XEXP (link, 0))));
+
+ for (i = first_regno; i < last_regno; i++)
+ CLEAR_HARD_REG_BIT (current_live_regs, i);
+ }
+ }
+
+ else if (GET_CODE (real_insn) == CODE_LABEL)
+ {
+ /* A label clobbers the pending dead registers since neither
+ reload nor jump will propagate a value across a label. */
+ AND_COMPL_HARD_REG_SET (current_live_regs, pending_dead_regs);
+ CLEAR_HARD_REG_SET (pending_dead_regs);
+ }
+
+ /* The beginning of the epilogue corresponds to the end of the
+ RTL chain when there are no epilogue insns. Certain resources
+ are implicitly required at that point. */
+ else if (GET_CODE (real_insn) == NOTE
+ && NOTE_LINE_NUMBER (real_insn) == NOTE_INSN_EPILOGUE_BEG)
+ IOR_HARD_REG_SET (current_live_regs, start_of_epilogue_needs.regs);
+ }
+
+ COPY_HARD_REG_SET (res->regs, current_live_regs);
+ if (tinfo != NULL)
+ {
+ tinfo->block = b;
+ tinfo->bb_tick = bb_ticks[b];
+ }
+ }
+ else
+ /* We didn't find the start of a basic block. Assume everything
+ in use. This should happen only extremely rarely. */
+ SET_HARD_REG_SET (res->regs);
+
+ CLEAR_RESOURCE (&set);
+ CLEAR_RESOURCE (&needed);
+
+ jump_insn = find_dead_or_set_registers (target, res, &jump_target, 0,
+ set, needed);
+
+ /* If we hit an unconditional branch, we have another way of finding out
+ what is live: we can see what is live at the branch target and include
+ anything used but not set before the branch. The only things that are
+ live are those that are live using the above test and the test below. */
+
+ if (jump_insn)
+ {
+ struct resources new_resources;
+ rtx stop_insn = next_active_insn (jump_insn);
+
+ mark_target_live_regs (insns, next_active_insn (jump_target),
+ &new_resources);
+ CLEAR_RESOURCE (&set);
+ CLEAR_RESOURCE (&needed);
+
+ /* Include JUMP_INSN in the needed registers. */
+ for (insn = target; insn != stop_insn; insn = next_active_insn (insn))
+ {
+ mark_referenced_resources (insn, &needed, 1);
+
+ COPY_HARD_REG_SET (scratch, needed.regs);
+ AND_COMPL_HARD_REG_SET (scratch, set.regs);
+ IOR_HARD_REG_SET (new_resources.regs, scratch);
+
+ mark_set_resources (insn, &set, 0, 1);
+ }
+
+ AND_HARD_REG_SET (res->regs, new_resources.regs);
+ }
+
+ if (tinfo != NULL)
+ {
+ COPY_HARD_REG_SET (tinfo->live_regs, res->regs);
+ }
+}
+\f
+/* Initialize the resources required by mark_target_live_regs ().
+ This should be invoked before the first call to mark_target_live_regs. */
+
+void
+init_resource_info (epilogue_insn)
+ rtx epilogue_insn;
+{
+ int i;
+
+ /* Indicate what resources are required to be valid at the end of the current
+ function. The condition code never is and memory always is. If the
+ frame pointer is needed, it is and so is the stack pointer unless
+ EXIT_IGNORE_STACK is non-zero. If the frame pointer is not needed, the
+ stack pointer is. Registers used to return the function value are
+ needed. Registers holding global variables are needed. */
+
+ end_of_function_needs.cc = 0;
+ end_of_function_needs.memory = 1;
+ end_of_function_needs.unch_memory = 0;
+ CLEAR_HARD_REG_SET (end_of_function_needs.regs);
+
+ if (frame_pointer_needed)
+ {
+ SET_HARD_REG_BIT (end_of_function_needs.regs, FRAME_POINTER_REGNUM);
+#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
+ SET_HARD_REG_BIT (end_of_function_needs.regs, HARD_FRAME_POINTER_REGNUM);
+#endif
+#ifdef EXIT_IGNORE_STACK
+ if (! EXIT_IGNORE_STACK
+ || current_function_sp_is_unchanging)
+#endif
+ SET_HARD_REG_BIT (end_of_function_needs.regs, STACK_POINTER_REGNUM);
+ }
+ else
+ SET_HARD_REG_BIT (end_of_function_needs.regs, STACK_POINTER_REGNUM);
+
+ if (current_function_return_rtx != 0)
+ mark_referenced_resources (current_function_return_rtx,
+ &end_of_function_needs, 1);
+
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (global_regs[i]
+#ifdef EPILOGUE_USES
+ || EPILOGUE_USES (i)
+#endif
+ )
+ SET_HARD_REG_BIT (end_of_function_needs.regs, i);
+
+ /* The registers required to be live at the end of the function are
+ represented in the flow information as being dead just prior to
+ reaching the end of the function. For example, the return of a value
+ might be represented by a USE of the return register immediately
+ followed by an unconditional jump to the return label where the
+ return label is the end of the RTL chain. The end of the RTL chain
+ is then taken to mean that the return register is live.
+
+ This sequence is no longer maintained when epilogue instructions are
+ added to the RTL chain. To reconstruct the original meaning, the
+ start of the epilogue (NOTE_INSN_EPILOGUE_BEG) is regarded as the
+ point where these registers become live (start_of_epilogue_needs).
+ If epilogue instructions are present, the registers set by those
+ instructions won't have been processed by flow. Thus, those
+ registers are additionally required at the end of the RTL chain
+ (end_of_function_needs). */
+
+ start_of_epilogue_needs = end_of_function_needs;
+
+ while ((epilogue_insn = next_nonnote_insn (epilogue_insn)))
+ mark_set_resources (epilogue_insn, &end_of_function_needs, 0, 1);
+
+ /* Allocate and initialize the tables used by mark_target_live_regs. */
+ target_hash_table
+ = (struct target_info **) xmalloc ((TARGET_HASH_PRIME
+ * sizeof (struct target_info *)));
+ bzero ((char *) target_hash_table,
+ TARGET_HASH_PRIME * sizeof (struct target_info *));
+
+ bb_ticks = (int *) xmalloc (n_basic_blocks * sizeof (int));
+ bzero ((char *) bb_ticks, n_basic_blocks * sizeof (int));
+}
+\f
+/* Free up the resources allcated to mark_target_live_regs (). This
+ should be invoked after the last call to mark_target_live_regs (). */
+
+void
+free_resource_info ()
+{
+ if (target_hash_table != NULL)
+ {
+ free (target_hash_table);
+ target_hash_table = NULL;
+ }
+
+ if (bb_ticks != NULL)
+ {
+ free (bb_ticks);
+ bb_ticks = NULL;
+ }
+}
+\f
+/* Clear any hashed information that we have stored for INSN. */
+
+void
+clear_hashed_info_for_insn (insn)
+ rtx insn;
+{
+ struct target_info *tinfo;
+
+ if (target_hash_table != NULL)
+ {
+ for (tinfo = target_hash_table[INSN_UID (insn) % TARGET_HASH_PRIME];
+ tinfo; tinfo = tinfo->next)
+ if (tinfo->uid == INSN_UID (insn))
+ break;
+
+ if (tinfo)
+ tinfo->block = -1;
+ }
+}
+\f
+/* Increment the tick count for the basic block that contains INSN. */
+
+void
+incr_ticks_for_insn (insn)
+ rtx insn;
+{
+ int b = find_basic_block (insn);
+
+ if (b != -1)
+ bb_ticks[b]++;
+}
+\f
+/* Add TRIAL to the set of resources used at the end of the current
+ function. */
+void
+mark_end_of_function_resources (trial, include_delayed_effects)
+ rtx trial;
+ int include_delayed_effects;
+{
+ mark_referenced_resources (trial, &end_of_function_needs,
+ include_delayed_effects);
+}
+\f
+/* Try to find an available hard register of mode MODE at
+ CURRENT_INSN, matching the register class in CLASS_STR. Registers
+ that already have bits set in REG_SET will not be considered.
+
+ If an appropriate register is available, it will be returned and the
+ corresponding bit(s) in REG_SET will be set; otherwise, NULL_RTX is
+ returned. */
+
+rtx
+find_free_register (current_insn, class_str, mode, reg_set)
+ rtx current_insn;
+ char *class_str;
+ int mode;
+ HARD_REG_SET *reg_set;
+{
+ int i, j;
+ struct resources used;
+ unsigned char clet = class_str[0];
+ enum reg_class class
+ = (clet == 'r' ? GENERAL_REGS : REG_CLASS_FROM_LETTER (clet));
+
+ mark_target_live_regs (get_insns (), current_insn, &used);
+
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ {
+ int success = 1;
+
+ if (! TEST_HARD_REG_BIT (reg_class_contents[class], i))
+ continue;
+ for (j = HARD_REGNO_NREGS (i, mode) - 1; j >= 0; j--)
+ {
+ if (TEST_HARD_REG_BIT (*reg_set, i + j)
+ || TEST_HARD_REG_BIT (used.regs, i + j))
+ {
+ success = 0;
+ break;
+ }
+ }
+ if (success)
+ {
+ for (j = HARD_REGNO_NREGS (i, mode) - 1; j >= 0; j--)
+ {
+ SET_HARD_REG_BIT (*reg_set, i + j);
+ }
+ return gen_rtx_REG (mode, i);
+ }
+ }
+ return NULL_RTX;
+}
--- /dev/null
+/* Definitions for computing resource usage of specific insns.
+ Copyright (C) 1999 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU CC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU CC; see the file COPYING. If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
+
+/* Macro to clear all resources. */
+#define CLEAR_RESOURCE(RES) \
+ do { (RES)->memory = (RES)->unch_memory = (RES)->volatil = (RES)->cc = 0; \
+ CLEAR_HARD_REG_SET ((RES)->regs); } while (0)
+
+/* The resources used by a given insn. */
+struct resources
+{
+ char memory; /* Insn sets or needs a memory location. */
+ char unch_memory; /* Insn sets of needs a "unchanging" MEM. */
+ char volatil; /* Insn sets or needs a volatile memory loc. */
+ char cc; /* Insn sets or needs the condition codes. */
+ HARD_REG_SET regs; /* Which registers are set or needed. */
+};
+
+extern void mark_target_live_regs PROTO((rtx, rtx, struct resources *));
+extern void mark_set_resources PROTO((rtx, struct resources *, int,
+ int));
+extern void mark_referenced_resources PROTO((rtx, struct resources *, int));
+extern void clear_hashed_info_for_insn PROTO((rtx));
+extern void incr_ticks_for_insn PROTO((rtx));
+extern void mark_end_of_function_resources PROTO ((rtx, int));
+extern void init_resource_info PROTO((rtx));
+extern void free_resource_info PROTO((void));
+extern rtx find_free_register PROTO((rtx, char *, int,
+ HARD_REG_SET *));
static void finish_sometimes_live PROTO((struct sometimes *, int));
static rtx reemit_notes PROTO((rtx, rtx));
static void schedule_block PROTO((int, FILE *));
-static rtx regno_use_in PROTO((int, rtx));
static void split_hard_reg_notes PROTO((rtx, rtx, rtx));
static void new_insn_dead_notes PROTO((rtx, rtx, rtx, rtx));
static void update_n_sets PROTO((rtx, int));
-static void update_flow_info PROTO((rtx, rtx, rtx, rtx));
/* Main entry point of this file. */
void schedule_insns PROTO((FILE *));
return;
}
\f
-/* Subroutine of split_hard_reg_notes. Searches X for any reference to
- REGNO, returning the rtx of the reference found if any. Otherwise,
- returns 0. */
-
-static rtx
-regno_use_in (regno, x)
- int regno;
- rtx x;
-{
- register char *fmt;
- int i, j;
- rtx tem;
-
- if (GET_CODE (x) == REG && REGNO (x) == regno)
- return x;
-
- fmt = GET_RTX_FORMAT (GET_CODE (x));
- for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
- {
- if (fmt[i] == 'e')
- {
- if ((tem = regno_use_in (regno, XEXP (x, i))))
- return tem;
- }
- else if (fmt[i] == 'E')
- for (j = XVECLEN (x, i) - 1; j >= 0; j--)
- if ((tem = regno_use_in (regno , XVECEXP (x, i, j))))
- return tem;
- }
-
- return 0;
-}
-
/* Subroutine of update_flow_info. Determines whether any new REG_NOTEs are
needed for the hard register mentioned in the note. This can happen
if the reference to the hard register in the original insn was split into
the insns from FIRST to LAST inclusive that were created by splitting
ORIG_INSN. NOTES are the original REG_NOTES. */
-static void
+void
update_flow_info (notes, first, last, orig_insn)
rtx notes;
rtx first, last;
note_list = 0;
- for (insn = BLOCK_HEAD (b); ; insn = next)
- {
- rtx prev;
- rtx set;
-
- /* Can't use `next_real_insn' because that
- might go across CODE_LABELS and short-out basic blocks. */
- next = NEXT_INSN (insn);
- if (GET_CODE (insn) != INSN)
- {
- if (insn == BLOCK_END (b))
- break;
-
- continue;
- }
-
- /* Don't split no-op move insns. These should silently disappear
- later in final. Splitting such insns would break the code
- that handles REG_NO_CONFLICT blocks. */
- set = single_set (insn);
- if (set && rtx_equal_p (SET_SRC (set), SET_DEST (set)))
- {
- if (insn == BLOCK_END (b))
- break;
-
- /* Nops get in the way while scheduling, so delete them now if
- register allocation has already been done. It is too risky
- to try to do this before register allocation, and there are
- unlikely to be very many nops then anyways. */
- if (reload_completed)
- {
- PUT_CODE (insn, NOTE);
- NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
- NOTE_SOURCE_FILE (insn) = 0;
- }
-
- continue;
- }
-
- /* Split insns here to get max fine-grain parallelism. */
- prev = PREV_INSN (insn);
- /* It is probably not worthwhile to try to split again in the
- second pass. However, if flag_schedule_insns is not set,
- the first and only (if any) scheduling pass is after reload. */
- if (reload_completed == 0 || ! flag_schedule_insns)
- {
- rtx last, first = PREV_INSN (insn);
- rtx notes = REG_NOTES (insn);
-
- last = try_split (PATTERN (insn), insn, 1);
- if (last != insn)
- {
- /* try_split returns the NOTE that INSN became. */
- first = NEXT_INSN (first);
- update_flow_info (notes, first, last, insn);
-
- PUT_CODE (insn, NOTE);
- NOTE_SOURCE_FILE (insn) = 0;
- NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
- if (insn == BLOCK_HEAD (b))
- BLOCK_HEAD (b) = first;
- if (insn == BLOCK_END (b))
- {
- BLOCK_END (b) = last;
- break;
- }
- }
- }
-
- if (insn == BLOCK_END (b))
- break;
- }
+ split_block_insns (b, reload_completed == 0 || ! flag_schedule_insns);
schedule_block (b, dump_file);
projects / thirdparty / gcc.git / commitdiff
