71c0e7fc96
* basic-block.h: Fix comment formatting. * bt-load.c: Likewise. * builtins.c: Likewise. * c-common.c: Likewise. * c-common.h: Likewise. * c-format.c: Likewise. * coverage.c: Likewise. * cpplib.h: Likewise. * cpppch.c: Likewise. * dbxout.c: Likewise. * diagnostic.c: Likewise. * dwarf2out.c: Likewise. * expr.c: Likewise. * fold-const.c: Likewise. * function.c: Likewise. * gcc.c: Likewise. * gcov-io.c: Likewise. * gcov-io.h: Likewise. * gcov.c: Likewise. * profile.c: Likewise. * real.h: Likewise. * sched-deps.c: Likewise. From-SVN: r68369
1537 lines
47 KiB
C
1537 lines
47 KiB
C
/* Instruction scheduling pass. This file computes dependencies between
|
||
instructions.
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Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998,
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1999, 2000, 2001, 2002 Free Software Foundation, Inc.
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Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by,
|
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and currently maintained by, Jim Wilson (wilson@cygnus.com)
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||
|
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This file is part of GCC.
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||
|
||
GCC 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.
|
||
|
||
GCC 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 GCC; see the file COPYING. If not, write to the Free
|
||
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
|
||
02111-1307, USA. */
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||
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "toplev.h"
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#include "rtl.h"
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#include "tm_p.h"
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#include "hard-reg-set.h"
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#include "basic-block.h"
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#include "regs.h"
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#include "function.h"
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#include "flags.h"
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#include "insn-config.h"
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#include "insn-attr.h"
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#include "except.h"
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#include "toplev.h"
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#include "recog.h"
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#include "sched-int.h"
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#include "params.h"
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#include "cselib.h"
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#include "df.h"
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extern char *reg_known_equiv_p;
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extern rtx *reg_known_value;
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static regset_head reg_pending_sets_head;
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static regset_head reg_pending_clobbers_head;
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static regset_head reg_pending_uses_head;
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static regset reg_pending_sets;
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static regset reg_pending_clobbers;
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static regset reg_pending_uses;
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/* The following enumeration values tell us what dependencies we
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should use to implement the barrier. We use true-dependencies for
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TRUE_BARRIER and anti-dependencies for MOVE_BARRIER. */
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enum reg_pending_barrier_mode
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{
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NOT_A_BARRIER = 0,
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MOVE_BARRIER,
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TRUE_BARRIER
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};
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static enum reg_pending_barrier_mode reg_pending_barrier;
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||
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||
/* To speed up the test for duplicate dependency links we keep a
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record of dependencies created by add_dependence when the average
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number of instructions in a basic block is very large.
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Studies have shown that there is typically around 5 instructions between
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branches for typical C code. So we can make a guess that the average
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basic block is approximately 5 instructions long; we will choose 100X
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the average size as a very large basic block.
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Each insn has associated bitmaps for its dependencies. Each bitmap
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has enough entries to represent a dependency on any other insn in
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the insn chain. All bitmap for true dependencies cache is
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allocated then the rest two ones are also allocated. */
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static sbitmap *true_dependency_cache;
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static sbitmap *anti_dependency_cache;
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static sbitmap *output_dependency_cache;
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/* To speed up checking consistency of formed forward insn
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dependencies we use the following cache. Another possible solution
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could be switching off checking duplication of insns in forward
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dependencies. */
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#ifdef ENABLE_CHECKING
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static sbitmap *forward_dependency_cache;
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#endif
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static int deps_may_trap_p PARAMS ((rtx));
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static void add_dependence_list PARAMS ((rtx, rtx, enum reg_note));
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static void add_dependence_list_and_free PARAMS ((rtx, rtx *, enum reg_note));
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static void set_sched_group_p PARAMS ((rtx));
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static void flush_pending_lists PARAMS ((struct deps *, rtx, int, int));
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static void sched_analyze_1 PARAMS ((struct deps *, rtx, rtx));
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static void sched_analyze_2 PARAMS ((struct deps *, rtx, rtx));
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static void sched_analyze_insn PARAMS ((struct deps *, rtx, rtx, rtx));
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static rtx get_condition PARAMS ((rtx));
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static int conditions_mutex_p PARAMS ((rtx, rtx));
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/* Return nonzero if a load of the memory reference MEM can cause a trap. */
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static int
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deps_may_trap_p (mem)
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rtx mem;
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{
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rtx addr = XEXP (mem, 0);
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if (REG_P (addr)
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&& REGNO (addr) >= FIRST_PSEUDO_REGISTER
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&& reg_known_value[REGNO (addr)])
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addr = reg_known_value[REGNO (addr)];
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return rtx_addr_can_trap_p (addr);
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}
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/* Return the INSN_LIST containing INSN in LIST, or NULL
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if LIST does not contain INSN. */
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rtx
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find_insn_list (insn, list)
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rtx insn;
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rtx list;
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{
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while (list)
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{
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||
if (XEXP (list, 0) == insn)
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return list;
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list = XEXP (list, 1);
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}
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return 0;
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}
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/* Find the condition under which INSN is executed. */
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static rtx
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get_condition (insn)
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rtx insn;
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{
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rtx pat = PATTERN (insn);
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rtx cond;
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if (pat == 0)
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return 0;
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if (GET_CODE (pat) == COND_EXEC)
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return COND_EXEC_TEST (pat);
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if (GET_CODE (insn) != JUMP_INSN)
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return 0;
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||
if (GET_CODE (pat) != SET || SET_SRC (pat) != pc_rtx)
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return 0;
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if (GET_CODE (SET_DEST (pat)) != IF_THEN_ELSE)
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return 0;
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pat = SET_DEST (pat);
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cond = XEXP (pat, 0);
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if (GET_CODE (XEXP (cond, 1)) == LABEL_REF
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&& XEXP (cond, 2) == pc_rtx)
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return cond;
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else if (GET_CODE (XEXP (cond, 2)) == LABEL_REF
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&& XEXP (cond, 1) == pc_rtx)
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return gen_rtx_fmt_ee (reverse_condition (GET_CODE (cond)), GET_MODE (cond),
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XEXP (cond, 0), XEXP (cond, 1));
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else
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return 0;
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}
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/* Return nonzero if conditions COND1 and COND2 can never be both true. */
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static int
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conditions_mutex_p (cond1, cond2)
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rtx cond1, cond2;
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{
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if (GET_RTX_CLASS (GET_CODE (cond1)) == '<'
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&& GET_RTX_CLASS (GET_CODE (cond2)) == '<'
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&& GET_CODE (cond1) == reverse_condition (GET_CODE (cond2))
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&& XEXP (cond1, 0) == XEXP (cond2, 0)
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&& XEXP (cond1, 1) == XEXP (cond2, 1))
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return 1;
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return 0;
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}
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/* Add ELEM wrapped in an INSN_LIST with reg note kind DEP_TYPE to the
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LOG_LINKS of INSN, if not already there. DEP_TYPE indicates the
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type of dependence that this link represents. The function returns
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nonzero if a new entry has been added to insn's LOG_LINK. */
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int
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add_dependence (insn, elem, dep_type)
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rtx insn;
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rtx elem;
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enum reg_note dep_type;
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{
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rtx link;
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int present_p;
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rtx cond1, cond2;
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/* Don't depend an insn on itself. */
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if (insn == elem)
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return 0;
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/* We can get a dependency on deleted insns due to optimizations in
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the register allocation and reloading or due to splitting. Any
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such dependency is useless and can be ignored. */
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if (GET_CODE (elem) == NOTE)
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return 0;
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/* flow.c doesn't handle conditional lifetimes entirely correctly;
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calls mess up the conditional lifetimes. */
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/* ??? add_dependence is the wrong place to be eliding dependencies,
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as that forgets that the condition expressions themselves may
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be dependent. */
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if (GET_CODE (insn) != CALL_INSN && GET_CODE (elem) != CALL_INSN)
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{
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cond1 = get_condition (insn);
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cond2 = get_condition (elem);
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if (cond1 && cond2
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&& conditions_mutex_p (cond1, cond2)
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/* Make sure first instruction doesn't affect condition of second
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instruction if switched. */
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&& !modified_in_p (cond1, elem)
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/* Make sure second instruction doesn't affect condition of first
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instruction if switched. */
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&& !modified_in_p (cond2, insn))
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return 0;
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}
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present_p = 1;
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#ifdef INSN_SCHEDULING
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/* ??? No good way to tell from here whether we're doing interblock
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scheduling. Possibly add another callback. */
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#if 0
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/* (This code is guarded by INSN_SCHEDULING, otherwise INSN_BB is undefined.)
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No need for interblock dependences with calls, since
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calls are not moved between blocks. Note: the edge where
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elem is a CALL is still required. */
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if (GET_CODE (insn) == CALL_INSN
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&& (INSN_BB (elem) != INSN_BB (insn)))
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return 0;
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#endif
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/* If we already have a dependency for ELEM, then we do not need to
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do anything. Avoiding the list walk below can cut compile times
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dramatically for some code. */
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if (true_dependency_cache != NULL)
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{
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enum reg_note present_dep_type = 0;
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if (anti_dependency_cache == NULL || output_dependency_cache == NULL)
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abort ();
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if (TEST_BIT (true_dependency_cache[INSN_LUID (insn)], INSN_LUID (elem)))
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/* Do nothing (present_set_type is already 0). */
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;
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else if (TEST_BIT (anti_dependency_cache[INSN_LUID (insn)],
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INSN_LUID (elem)))
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present_dep_type = REG_DEP_ANTI;
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else if (TEST_BIT (output_dependency_cache[INSN_LUID (insn)],
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INSN_LUID (elem)))
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present_dep_type = REG_DEP_OUTPUT;
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else
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present_p = 0;
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if (present_p && (int) dep_type >= (int) present_dep_type)
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return 0;
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}
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#endif
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/* Check that we don't already have this dependence. */
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if (present_p)
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for (link = LOG_LINKS (insn); link; link = XEXP (link, 1))
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if (XEXP (link, 0) == elem)
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{
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#ifdef INSN_SCHEDULING
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/* Clear corresponding cache entry because type of the link
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may be changed. */
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if (true_dependency_cache != NULL)
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{
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if (REG_NOTE_KIND (link) == REG_DEP_ANTI)
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RESET_BIT (anti_dependency_cache[INSN_LUID (insn)],
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INSN_LUID (elem));
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else if (REG_NOTE_KIND (link) == REG_DEP_OUTPUT
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&& output_dependency_cache)
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RESET_BIT (output_dependency_cache[INSN_LUID (insn)],
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INSN_LUID (elem));
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else
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abort ();
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}
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#endif
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/* If this is a more restrictive type of dependence than the existing
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one, then change the existing dependence to this type. */
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if ((int) dep_type < (int) REG_NOTE_KIND (link))
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PUT_REG_NOTE_KIND (link, dep_type);
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#ifdef INSN_SCHEDULING
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/* If we are adding a dependency to INSN's LOG_LINKs, then
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note that in the bitmap caches of dependency information. */
|
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if (true_dependency_cache != NULL)
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{
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if ((int) REG_NOTE_KIND (link) == 0)
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SET_BIT (true_dependency_cache[INSN_LUID (insn)],
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INSN_LUID (elem));
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else if (REG_NOTE_KIND (link) == REG_DEP_ANTI)
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SET_BIT (anti_dependency_cache[INSN_LUID (insn)],
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INSN_LUID (elem));
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else if (REG_NOTE_KIND (link) == REG_DEP_OUTPUT)
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SET_BIT (output_dependency_cache[INSN_LUID (insn)],
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INSN_LUID (elem));
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}
|
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#endif
|
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return 0;
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}
|
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/* Might want to check one level of transitivity to save conses. */
|
||
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link = alloc_INSN_LIST (elem, LOG_LINKS (insn));
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LOG_LINKS (insn) = link;
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|
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/* Insn dependency, not data dependency. */
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PUT_REG_NOTE_KIND (link, dep_type);
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|
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#ifdef INSN_SCHEDULING
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/* If we are adding a dependency to INSN's LOG_LINKs, then note that
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in the bitmap caches of dependency information. */
|
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if (true_dependency_cache != NULL)
|
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{
|
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if ((int) dep_type == 0)
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SET_BIT (true_dependency_cache[INSN_LUID (insn)], INSN_LUID (elem));
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else if (dep_type == REG_DEP_ANTI)
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SET_BIT (anti_dependency_cache[INSN_LUID (insn)], INSN_LUID (elem));
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else if (dep_type == REG_DEP_OUTPUT)
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SET_BIT (output_dependency_cache[INSN_LUID (insn)], INSN_LUID (elem));
|
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}
|
||
#endif
|
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return 1;
|
||
}
|
||
|
||
/* A convenience wrapper to operate on an entire list. */
|
||
|
||
static void
|
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add_dependence_list (insn, list, dep_type)
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rtx insn, list;
|
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enum reg_note dep_type;
|
||
{
|
||
for (; list; list = XEXP (list, 1))
|
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add_dependence (insn, XEXP (list, 0), dep_type);
|
||
}
|
||
|
||
/* Similar, but free *LISTP at the same time. */
|
||
|
||
static void
|
||
add_dependence_list_and_free (insn, listp, dep_type)
|
||
rtx insn;
|
||
rtx *listp;
|
||
enum reg_note dep_type;
|
||
{
|
||
rtx list, next;
|
||
for (list = *listp, *listp = NULL; list ; list = next)
|
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{
|
||
next = XEXP (list, 1);
|
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add_dependence (insn, XEXP (list, 0), dep_type);
|
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free_INSN_LIST_node (list);
|
||
}
|
||
}
|
||
|
||
/* Set SCHED_GROUP_P and care for the rest of the bookkeeping that
|
||
goes along with that. */
|
||
|
||
static void
|
||
set_sched_group_p (insn)
|
||
rtx insn;
|
||
{
|
||
rtx prev;
|
||
|
||
SCHED_GROUP_P (insn) = 1;
|
||
|
||
prev = prev_nonnote_insn (insn);
|
||
add_dependence (insn, prev, REG_DEP_ANTI);
|
||
}
|
||
|
||
/* Process an insn's memory dependencies. There are four kinds of
|
||
dependencies:
|
||
|
||
(0) read dependence: read follows read
|
||
(1) true dependence: read follows write
|
||
(2) anti dependence: write follows read
|
||
(3) output dependence: write follows write
|
||
|
||
We are careful to build only dependencies which actually exist, and
|
||
use transitivity to avoid building too many links. */
|
||
|
||
/* Add an INSN and MEM reference pair to a pending INSN_LIST and MEM_LIST.
|
||
The MEM is a memory reference contained within INSN, which we are saving
|
||
so that we can do memory aliasing on it. */
|
||
|
||
void
|
||
add_insn_mem_dependence (deps, insn_list, mem_list, insn, mem)
|
||
struct deps *deps;
|
||
rtx *insn_list, *mem_list, insn, mem;
|
||
{
|
||
rtx link;
|
||
|
||
link = alloc_INSN_LIST (insn, *insn_list);
|
||
*insn_list = link;
|
||
|
||
if (current_sched_info->use_cselib)
|
||
{
|
||
mem = shallow_copy_rtx (mem);
|
||
XEXP (mem, 0) = cselib_subst_to_values (XEXP (mem, 0));
|
||
}
|
||
link = alloc_EXPR_LIST (VOIDmode, mem, *mem_list);
|
||
*mem_list = link;
|
||
|
||
deps->pending_lists_length++;
|
||
}
|
||
|
||
/* Make a dependency between every memory reference on the pending lists
|
||
and INSN, thus flushing the pending lists. FOR_READ is true if emitting
|
||
dependencies for a read operation, similarly with FOR_WRITE. */
|
||
|
||
static void
|
||
flush_pending_lists (deps, insn, for_read, for_write)
|
||
struct deps *deps;
|
||
rtx insn;
|
||
int for_read, for_write;
|
||
{
|
||
if (for_write)
|
||
{
|
||
add_dependence_list_and_free (insn, &deps->pending_read_insns,
|
||
REG_DEP_ANTI);
|
||
free_EXPR_LIST_list (&deps->pending_read_mems);
|
||
}
|
||
|
||
add_dependence_list_and_free (insn, &deps->pending_write_insns,
|
||
for_read ? REG_DEP_ANTI : REG_DEP_OUTPUT);
|
||
free_EXPR_LIST_list (&deps->pending_write_mems);
|
||
deps->pending_lists_length = 0;
|
||
|
||
add_dependence_list_and_free (insn, &deps->last_pending_memory_flush,
|
||
for_read ? REG_DEP_ANTI : REG_DEP_OUTPUT);
|
||
deps->last_pending_memory_flush = alloc_INSN_LIST (insn, NULL_RTX);
|
||
deps->pending_flush_length = 1;
|
||
}
|
||
|
||
/* Analyze a single SET, CLOBBER, PRE_DEC, POST_DEC, PRE_INC or POST_INC
|
||
rtx, X, creating all dependencies generated by the write to the
|
||
destination of X, and reads of everything mentioned. */
|
||
|
||
static void
|
||
sched_analyze_1 (deps, x, insn)
|
||
struct deps *deps;
|
||
rtx x;
|
||
rtx insn;
|
||
{
|
||
int regno;
|
||
rtx dest = XEXP (x, 0);
|
||
enum rtx_code code = GET_CODE (x);
|
||
|
||
if (dest == 0)
|
||
return;
|
||
|
||
if (GET_CODE (dest) == PARALLEL)
|
||
{
|
||
int i;
|
||
|
||
for (i = XVECLEN (dest, 0) - 1; i >= 0; i--)
|
||
if (XEXP (XVECEXP (dest, 0, i), 0) != 0)
|
||
sched_analyze_1 (deps,
|
||
gen_rtx_CLOBBER (VOIDmode,
|
||
XEXP (XVECEXP (dest, 0, i), 0)),
|
||
insn);
|
||
|
||
if (GET_CODE (x) == SET)
|
||
sched_analyze_2 (deps, SET_SRC (x), insn);
|
||
return;
|
||
}
|
||
|
||
while (GET_CODE (dest) == STRICT_LOW_PART || GET_CODE (dest) == SUBREG
|
||
|| GET_CODE (dest) == ZERO_EXTRACT || GET_CODE (dest) == SIGN_EXTRACT)
|
||
{
|
||
if (GET_CODE (dest) == STRICT_LOW_PART
|
||
|| GET_CODE (dest) == ZERO_EXTRACT
|
||
|| GET_CODE (dest) == SIGN_EXTRACT
|
||
|| read_modify_subreg_p (dest))
|
||
{
|
||
/* These both read and modify the result. We must handle
|
||
them as writes to get proper dependencies for following
|
||
instructions. We must handle them as reads to get proper
|
||
dependencies from this to previous instructions.
|
||
Thus we need to call sched_analyze_2. */
|
||
|
||
sched_analyze_2 (deps, XEXP (dest, 0), insn);
|
||
}
|
||
if (GET_CODE (dest) == ZERO_EXTRACT || GET_CODE (dest) == SIGN_EXTRACT)
|
||
{
|
||
/* The second and third arguments are values read by this insn. */
|
||
sched_analyze_2 (deps, XEXP (dest, 1), insn);
|
||
sched_analyze_2 (deps, XEXP (dest, 2), insn);
|
||
}
|
||
dest = XEXP (dest, 0);
|
||
}
|
||
|
||
if (GET_CODE (dest) == REG)
|
||
{
|
||
regno = REGNO (dest);
|
||
|
||
/* A hard reg in a wide mode may really be multiple registers.
|
||
If so, mark all of them just like the first. */
|
||
if (regno < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
int i = HARD_REGNO_NREGS (regno, GET_MODE (dest));
|
||
if (code == SET)
|
||
{
|
||
while (--i >= 0)
|
||
SET_REGNO_REG_SET (reg_pending_sets, regno + i);
|
||
}
|
||
else
|
||
{
|
||
while (--i >= 0)
|
||
SET_REGNO_REG_SET (reg_pending_clobbers, regno + i);
|
||
}
|
||
}
|
||
/* ??? Reload sometimes emits USEs and CLOBBERs of pseudos that
|
||
it does not reload. Ignore these as they have served their
|
||
purpose already. */
|
||
else if (regno >= deps->max_reg)
|
||
{
|
||
if (GET_CODE (PATTERN (insn)) != USE
|
||
&& GET_CODE (PATTERN (insn)) != CLOBBER)
|
||
abort ();
|
||
}
|
||
else
|
||
{
|
||
if (code == SET)
|
||
SET_REGNO_REG_SET (reg_pending_sets, regno);
|
||
else
|
||
SET_REGNO_REG_SET (reg_pending_clobbers, regno);
|
||
|
||
/* Pseudos that are REG_EQUIV to something may be replaced
|
||
by that during reloading. We need only add dependencies for
|
||
the address in the REG_EQUIV note. */
|
||
if (!reload_completed
|
||
&& reg_known_equiv_p[regno]
|
||
&& GET_CODE (reg_known_value[regno]) == MEM)
|
||
sched_analyze_2 (deps, XEXP (reg_known_value[regno], 0), insn);
|
||
|
||
/* Don't let it cross a call after scheduling if it doesn't
|
||
already cross one. */
|
||
if (REG_N_CALLS_CROSSED (regno) == 0)
|
||
add_dependence_list (insn, deps->last_function_call, REG_DEP_ANTI);
|
||
}
|
||
}
|
||
else if (GET_CODE (dest) == MEM)
|
||
{
|
||
/* Writing memory. */
|
||
rtx t = dest;
|
||
|
||
if (current_sched_info->use_cselib)
|
||
{
|
||
t = shallow_copy_rtx (dest);
|
||
cselib_lookup (XEXP (t, 0), Pmode, 1);
|
||
XEXP (t, 0) = cselib_subst_to_values (XEXP (t, 0));
|
||
}
|
||
|
||
if (deps->pending_lists_length > MAX_PENDING_LIST_LENGTH)
|
||
{
|
||
/* Flush all pending reads and writes to prevent the pending lists
|
||
from getting any larger. Insn scheduling runs too slowly when
|
||
these lists get long. When compiling GCC with itself,
|
||
this flush occurs 8 times for sparc, and 10 times for m88k using
|
||
the default value of 32. */
|
||
flush_pending_lists (deps, insn, false, true);
|
||
}
|
||
else
|
||
{
|
||
rtx pending, pending_mem;
|
||
|
||
pending = deps->pending_read_insns;
|
||
pending_mem = deps->pending_read_mems;
|
||
while (pending)
|
||
{
|
||
if (anti_dependence (XEXP (pending_mem, 0), t))
|
||
add_dependence (insn, XEXP (pending, 0), REG_DEP_ANTI);
|
||
|
||
pending = XEXP (pending, 1);
|
||
pending_mem = XEXP (pending_mem, 1);
|
||
}
|
||
|
||
pending = deps->pending_write_insns;
|
||
pending_mem = deps->pending_write_mems;
|
||
while (pending)
|
||
{
|
||
if (output_dependence (XEXP (pending_mem, 0), t))
|
||
add_dependence (insn, XEXP (pending, 0), REG_DEP_OUTPUT);
|
||
|
||
pending = XEXP (pending, 1);
|
||
pending_mem = XEXP (pending_mem, 1);
|
||
}
|
||
|
||
add_dependence_list (insn, deps->last_pending_memory_flush,
|
||
REG_DEP_ANTI);
|
||
|
||
add_insn_mem_dependence (deps, &deps->pending_write_insns,
|
||
&deps->pending_write_mems, insn, dest);
|
||
}
|
||
sched_analyze_2 (deps, XEXP (dest, 0), insn);
|
||
}
|
||
|
||
/* Analyze reads. */
|
||
if (GET_CODE (x) == SET)
|
||
sched_analyze_2 (deps, SET_SRC (x), insn);
|
||
}
|
||
|
||
/* Analyze the uses of memory and registers in rtx X in INSN. */
|
||
|
||
static void
|
||
sched_analyze_2 (deps, x, insn)
|
||
struct deps *deps;
|
||
rtx x;
|
||
rtx insn;
|
||
{
|
||
int i;
|
||
int j;
|
||
enum rtx_code code;
|
||
const char *fmt;
|
||
|
||
if (x == 0)
|
||
return;
|
||
|
||
code = GET_CODE (x);
|
||
|
||
switch (code)
|
||
{
|
||
case CONST_INT:
|
||
case CONST_DOUBLE:
|
||
case CONST_VECTOR:
|
||
case SYMBOL_REF:
|
||
case CONST:
|
||
case LABEL_REF:
|
||
/* Ignore constants. Note that we must handle CONST_DOUBLE here
|
||
because it may have a cc0_rtx in its CONST_DOUBLE_CHAIN field, but
|
||
this does not mean that this insn is using cc0. */
|
||
return;
|
||
|
||
#ifdef HAVE_cc0
|
||
case CC0:
|
||
/* User of CC0 depends on immediately preceding insn. */
|
||
set_sched_group_p (insn);
|
||
return;
|
||
#endif
|
||
|
||
case REG:
|
||
{
|
||
int regno = REGNO (x);
|
||
if (regno < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
int i = HARD_REGNO_NREGS (regno, GET_MODE (x));
|
||
while (--i >= 0)
|
||
SET_REGNO_REG_SET (reg_pending_uses, regno + i);
|
||
}
|
||
/* ??? Reload sometimes emits USEs and CLOBBERs of pseudos that
|
||
it does not reload. Ignore these as they have served their
|
||
purpose already. */
|
||
else if (regno >= deps->max_reg)
|
||
{
|
||
if (GET_CODE (PATTERN (insn)) != USE
|
||
&& GET_CODE (PATTERN (insn)) != CLOBBER)
|
||
abort ();
|
||
}
|
||
else
|
||
{
|
||
SET_REGNO_REG_SET (reg_pending_uses, regno);
|
||
|
||
/* Pseudos that are REG_EQUIV to something may be replaced
|
||
by that during reloading. We need only add dependencies for
|
||
the address in the REG_EQUIV note. */
|
||
if (!reload_completed
|
||
&& reg_known_equiv_p[regno]
|
||
&& GET_CODE (reg_known_value[regno]) == MEM)
|
||
sched_analyze_2 (deps, XEXP (reg_known_value[regno], 0), insn);
|
||
|
||
/* If the register does not already cross any calls, then add this
|
||
insn to the sched_before_next_call list so that it will still
|
||
not cross calls after scheduling. */
|
||
if (REG_N_CALLS_CROSSED (regno) == 0)
|
||
deps->sched_before_next_call
|
||
= alloc_INSN_LIST (insn, deps->sched_before_next_call);
|
||
}
|
||
return;
|
||
}
|
||
|
||
case MEM:
|
||
{
|
||
/* Reading memory. */
|
||
rtx u;
|
||
rtx pending, pending_mem;
|
||
rtx t = x;
|
||
|
||
if (current_sched_info->use_cselib)
|
||
{
|
||
t = shallow_copy_rtx (t);
|
||
cselib_lookup (XEXP (t, 0), Pmode, 1);
|
||
XEXP (t, 0) = cselib_subst_to_values (XEXP (t, 0));
|
||
}
|
||
pending = deps->pending_read_insns;
|
||
pending_mem = deps->pending_read_mems;
|
||
while (pending)
|
||
{
|
||
if (read_dependence (XEXP (pending_mem, 0), t))
|
||
add_dependence (insn, XEXP (pending, 0), REG_DEP_ANTI);
|
||
|
||
pending = XEXP (pending, 1);
|
||
pending_mem = XEXP (pending_mem, 1);
|
||
}
|
||
|
||
pending = deps->pending_write_insns;
|
||
pending_mem = deps->pending_write_mems;
|
||
while (pending)
|
||
{
|
||
if (true_dependence (XEXP (pending_mem, 0), VOIDmode,
|
||
t, rtx_varies_p))
|
||
add_dependence (insn, XEXP (pending, 0), 0);
|
||
|
||
pending = XEXP (pending, 1);
|
||
pending_mem = XEXP (pending_mem, 1);
|
||
}
|
||
|
||
for (u = deps->last_pending_memory_flush; u; u = XEXP (u, 1))
|
||
if (GET_CODE (XEXP (u, 0)) != JUMP_INSN
|
||
|| deps_may_trap_p (x))
|
||
add_dependence (insn, XEXP (u, 0), REG_DEP_ANTI);
|
||
|
||
/* Always add these dependencies to pending_reads, since
|
||
this insn may be followed by a write. */
|
||
add_insn_mem_dependence (deps, &deps->pending_read_insns,
|
||
&deps->pending_read_mems, insn, x);
|
||
|
||
/* Take advantage of tail recursion here. */
|
||
sched_analyze_2 (deps, XEXP (x, 0), insn);
|
||
return;
|
||
}
|
||
|
||
/* Force pending stores to memory in case a trap handler needs them. */
|
||
case TRAP_IF:
|
||
flush_pending_lists (deps, insn, true, false);
|
||
break;
|
||
|
||
case ASM_OPERANDS:
|
||
case ASM_INPUT:
|
||
case UNSPEC_VOLATILE:
|
||
{
|
||
/* Traditional and volatile asm instructions must be considered to use
|
||
and clobber all hard registers, all pseudo-registers and all of
|
||
memory. So must TRAP_IF and UNSPEC_VOLATILE operations.
|
||
|
||
Consider for instance a volatile asm that changes the fpu rounding
|
||
mode. An insn should not be moved across this even if it only uses
|
||
pseudo-regs because it might give an incorrectly rounded result. */
|
||
if (code != ASM_OPERANDS || MEM_VOLATILE_P (x))
|
||
reg_pending_barrier = TRUE_BARRIER;
|
||
|
||
/* 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. */
|
||
|
||
if (code == ASM_OPERANDS)
|
||
{
|
||
for (j = 0; j < ASM_OPERANDS_INPUT_LENGTH (x); j++)
|
||
sched_analyze_2 (deps, ASM_OPERANDS_INPUT (x, j), insn);
|
||
return;
|
||
}
|
||
break;
|
||
}
|
||
|
||
case PRE_DEC:
|
||
case POST_DEC:
|
||
case PRE_INC:
|
||
case POST_INC:
|
||
/* These both read and modify the result. We must handle them as writes
|
||
to get proper dependencies for following instructions. We must handle
|
||
them as reads to get proper dependencies from this to previous
|
||
instructions. Thus we need to pass them to both sched_analyze_1
|
||
and sched_analyze_2. We must call sched_analyze_2 first in order
|
||
to get the proper antecedent for the read. */
|
||
sched_analyze_2 (deps, XEXP (x, 0), insn);
|
||
sched_analyze_1 (deps, x, insn);
|
||
return;
|
||
|
||
case POST_MODIFY:
|
||
case PRE_MODIFY:
|
||
/* op0 = op0 + op1 */
|
||
sched_analyze_2 (deps, XEXP (x, 0), insn);
|
||
sched_analyze_2 (deps, XEXP (x, 1), insn);
|
||
sched_analyze_1 (deps, x, insn);
|
||
return;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
/* Other cases: walk the insn. */
|
||
fmt = GET_RTX_FORMAT (code);
|
||
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
|
||
{
|
||
if (fmt[i] == 'e')
|
||
sched_analyze_2 (deps, XEXP (x, i), insn);
|
||
else if (fmt[i] == 'E')
|
||
for (j = 0; j < XVECLEN (x, i); j++)
|
||
sched_analyze_2 (deps, XVECEXP (x, i, j), insn);
|
||
}
|
||
}
|
||
|
||
/* Analyze an INSN with pattern X to find all dependencies. */
|
||
|
||
static void
|
||
sched_analyze_insn (deps, x, insn, loop_notes)
|
||
struct deps *deps;
|
||
rtx x, insn;
|
||
rtx loop_notes;
|
||
{
|
||
RTX_CODE code = GET_CODE (x);
|
||
rtx link;
|
||
int i;
|
||
|
||
if (code == COND_EXEC)
|
||
{
|
||
sched_analyze_2 (deps, COND_EXEC_TEST (x), insn);
|
||
|
||
/* ??? Should be recording conditions so we reduce the number of
|
||
false dependencies. */
|
||
x = COND_EXEC_CODE (x);
|
||
code = GET_CODE (x);
|
||
}
|
||
if (code == SET || code == CLOBBER)
|
||
{
|
||
sched_analyze_1 (deps, x, insn);
|
||
|
||
/* Bare clobber insns are used for letting life analysis, reg-stack
|
||
and others know that a value is dead. Depend on the last call
|
||
instruction so that reg-stack won't get confused. */
|
||
if (code == CLOBBER)
|
||
add_dependence_list (insn, deps->last_function_call, REG_DEP_OUTPUT);
|
||
}
|
||
else if (code == PARALLEL)
|
||
{
|
||
int i;
|
||
for (i = XVECLEN (x, 0) - 1; i >= 0; i--)
|
||
{
|
||
rtx sub = XVECEXP (x, 0, i);
|
||
code = GET_CODE (sub);
|
||
|
||
if (code == COND_EXEC)
|
||
{
|
||
sched_analyze_2 (deps, COND_EXEC_TEST (sub), insn);
|
||
sub = COND_EXEC_CODE (sub);
|
||
code = GET_CODE (sub);
|
||
}
|
||
if (code == SET || code == CLOBBER)
|
||
sched_analyze_1 (deps, sub, insn);
|
||
else
|
||
sched_analyze_2 (deps, sub, insn);
|
||
}
|
||
}
|
||
else
|
||
sched_analyze_2 (deps, x, insn);
|
||
|
||
/* Mark registers CLOBBERED or used by called function. */
|
||
if (GET_CODE (insn) == CALL_INSN)
|
||
{
|
||
for (link = CALL_INSN_FUNCTION_USAGE (insn); link; link = XEXP (link, 1))
|
||
{
|
||
if (GET_CODE (XEXP (link, 0)) == CLOBBER)
|
||
sched_analyze_1 (deps, XEXP (link, 0), insn);
|
||
else
|
||
sched_analyze_2 (deps, XEXP (link, 0), insn);
|
||
}
|
||
if (find_reg_note (insn, REG_SETJMP, NULL))
|
||
reg_pending_barrier = MOVE_BARRIER;
|
||
}
|
||
|
||
if (GET_CODE (insn) == JUMP_INSN)
|
||
{
|
||
rtx next;
|
||
next = next_nonnote_insn (insn);
|
||
if (next && GET_CODE (next) == BARRIER)
|
||
reg_pending_barrier = TRUE_BARRIER;
|
||
else
|
||
{
|
||
rtx pending, pending_mem;
|
||
regset_head tmp;
|
||
INIT_REG_SET (&tmp);
|
||
|
||
(*current_sched_info->compute_jump_reg_dependencies) (insn, &tmp);
|
||
/* Make latency of jump equal to 0 by using anti-dependence. */
|
||
EXECUTE_IF_SET_IN_REG_SET (&tmp, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
add_dependence_list (insn, reg_last->sets, REG_DEP_ANTI);
|
||
add_dependence_list (insn, reg_last->clobbers, REG_DEP_ANTI);
|
||
reg_last->uses_length++;
|
||
reg_last->uses = alloc_INSN_LIST (insn, reg_last->uses);
|
||
});
|
||
CLEAR_REG_SET (&tmp);
|
||
|
||
/* All memory writes and volatile reads must happen before the
|
||
jump. Non-volatile reads must happen before the jump iff
|
||
the result is needed by the above register used mask. */
|
||
|
||
pending = deps->pending_write_insns;
|
||
pending_mem = deps->pending_write_mems;
|
||
while (pending)
|
||
{
|
||
add_dependence (insn, XEXP (pending, 0), REG_DEP_OUTPUT);
|
||
pending = XEXP (pending, 1);
|
||
pending_mem = XEXP (pending_mem, 1);
|
||
}
|
||
|
||
pending = deps->pending_read_insns;
|
||
pending_mem = deps->pending_read_mems;
|
||
while (pending)
|
||
{
|
||
if (MEM_VOLATILE_P (XEXP (pending_mem, 0)))
|
||
add_dependence (insn, XEXP (pending, 0), REG_DEP_OUTPUT);
|
||
pending = XEXP (pending, 1);
|
||
pending_mem = XEXP (pending_mem, 1);
|
||
}
|
||
|
||
add_dependence_list (insn, deps->last_pending_memory_flush,
|
||
REG_DEP_ANTI);
|
||
}
|
||
}
|
||
|
||
/* If there is a {LOOP,EHREGION}_{BEG,END} note in the middle of a basic
|
||
block, then we must be sure that no instructions are scheduled across it.
|
||
Otherwise, the reg_n_refs info (which depends on loop_depth) would
|
||
become incorrect. */
|
||
if (loop_notes)
|
||
{
|
||
rtx link;
|
||
|
||
/* Update loop_notes with any notes from this insn. Also determine
|
||
if any of the notes on the list correspond to instruction scheduling
|
||
barriers (loop, eh & setjmp notes, but not range notes). */
|
||
link = loop_notes;
|
||
while (XEXP (link, 1))
|
||
{
|
||
if (INTVAL (XEXP (link, 0)) == NOTE_INSN_LOOP_BEG
|
||
|| INTVAL (XEXP (link, 0)) == NOTE_INSN_LOOP_END
|
||
|| INTVAL (XEXP (link, 0)) == NOTE_INSN_EH_REGION_BEG
|
||
|| INTVAL (XEXP (link, 0)) == NOTE_INSN_EH_REGION_END)
|
||
reg_pending_barrier = MOVE_BARRIER;
|
||
|
||
link = XEXP (link, 1);
|
||
}
|
||
XEXP (link, 1) = REG_NOTES (insn);
|
||
REG_NOTES (insn) = loop_notes;
|
||
}
|
||
|
||
/* If this instruction can throw an exception, then moving it changes
|
||
where block boundaries fall. This is mighty confusing elsewhere.
|
||
Therefore, prevent such an instruction from being moved. */
|
||
if (can_throw_internal (insn))
|
||
reg_pending_barrier = MOVE_BARRIER;
|
||
|
||
/* Add dependencies if a scheduling barrier was found. */
|
||
if (reg_pending_barrier)
|
||
{
|
||
/* In the case of barrier the most added dependencies are not
|
||
real, so we use anti-dependence here. */
|
||
if (GET_CODE (PATTERN (insn)) == COND_EXEC)
|
||
{
|
||
EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
add_dependence_list (insn, reg_last->uses, REG_DEP_ANTI);
|
||
add_dependence_list
|
||
(insn, reg_last->sets,
|
||
reg_pending_barrier == TRUE_BARRIER ? 0 : REG_DEP_ANTI);
|
||
add_dependence_list
|
||
(insn, reg_last->clobbers,
|
||
reg_pending_barrier == TRUE_BARRIER ? 0 : REG_DEP_ANTI);
|
||
});
|
||
}
|
||
else
|
||
{
|
||
EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
add_dependence_list_and_free (insn, ®_last->uses,
|
||
REG_DEP_ANTI);
|
||
add_dependence_list_and_free
|
||
(insn, ®_last->sets,
|
||
reg_pending_barrier == TRUE_BARRIER ? 0 : REG_DEP_ANTI);
|
||
add_dependence_list_and_free
|
||
(insn, ®_last->clobbers,
|
||
reg_pending_barrier == TRUE_BARRIER ? 0 : REG_DEP_ANTI);
|
||
reg_last->uses_length = 0;
|
||
reg_last->clobbers_length = 0;
|
||
});
|
||
}
|
||
|
||
for (i = 0; i < deps->max_reg; i++)
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
|
||
SET_REGNO_REG_SET (&deps->reg_last_in_use, i);
|
||
}
|
||
|
||
flush_pending_lists (deps, insn, true, true);
|
||
reg_pending_barrier = NOT_A_BARRIER;
|
||
}
|
||
else
|
||
{
|
||
/* If the current insn is conditional, we can't free any
|
||
of the lists. */
|
||
if (GET_CODE (PATTERN (insn)) == COND_EXEC)
|
||
{
|
||
EXECUTE_IF_SET_IN_REG_SET (reg_pending_uses, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
add_dependence_list (insn, reg_last->sets, 0);
|
||
add_dependence_list (insn, reg_last->clobbers, 0);
|
||
reg_last->uses = alloc_INSN_LIST (insn, reg_last->uses);
|
||
reg_last->uses_length++;
|
||
});
|
||
EXECUTE_IF_SET_IN_REG_SET (reg_pending_clobbers, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
add_dependence_list (insn, reg_last->sets, REG_DEP_OUTPUT);
|
||
add_dependence_list (insn, reg_last->uses, REG_DEP_ANTI);
|
||
reg_last->clobbers = alloc_INSN_LIST (insn, reg_last->clobbers);
|
||
reg_last->clobbers_length++;
|
||
});
|
||
EXECUTE_IF_SET_IN_REG_SET (reg_pending_sets, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
add_dependence_list (insn, reg_last->sets, REG_DEP_OUTPUT);
|
||
add_dependence_list (insn, reg_last->clobbers, REG_DEP_OUTPUT);
|
||
add_dependence_list (insn, reg_last->uses, REG_DEP_ANTI);
|
||
reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
|
||
});
|
||
}
|
||
else
|
||
{
|
||
EXECUTE_IF_SET_IN_REG_SET (reg_pending_uses, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
add_dependence_list (insn, reg_last->sets, 0);
|
||
add_dependence_list (insn, reg_last->clobbers, 0);
|
||
reg_last->uses_length++;
|
||
reg_last->uses = alloc_INSN_LIST (insn, reg_last->uses);
|
||
});
|
||
EXECUTE_IF_SET_IN_REG_SET (reg_pending_clobbers, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
if (reg_last->uses_length > MAX_PENDING_LIST_LENGTH
|
||
|| reg_last->clobbers_length > MAX_PENDING_LIST_LENGTH)
|
||
{
|
||
add_dependence_list_and_free (insn, ®_last->sets,
|
||
REG_DEP_OUTPUT);
|
||
add_dependence_list_and_free (insn, ®_last->uses,
|
||
REG_DEP_ANTI);
|
||
add_dependence_list_and_free (insn, ®_last->clobbers,
|
||
REG_DEP_OUTPUT);
|
||
reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
|
||
reg_last->clobbers_length = 0;
|
||
reg_last->uses_length = 0;
|
||
}
|
||
else
|
||
{
|
||
add_dependence_list (insn, reg_last->sets, REG_DEP_OUTPUT);
|
||
add_dependence_list (insn, reg_last->uses, REG_DEP_ANTI);
|
||
}
|
||
reg_last->clobbers_length++;
|
||
reg_last->clobbers = alloc_INSN_LIST (insn, reg_last->clobbers);
|
||
});
|
||
EXECUTE_IF_SET_IN_REG_SET (reg_pending_sets, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
add_dependence_list_and_free (insn, ®_last->sets,
|
||
REG_DEP_OUTPUT);
|
||
add_dependence_list_and_free (insn, ®_last->clobbers,
|
||
REG_DEP_OUTPUT);
|
||
add_dependence_list_and_free (insn, ®_last->uses,
|
||
REG_DEP_ANTI);
|
||
reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
|
||
reg_last->uses_length = 0;
|
||
reg_last->clobbers_length = 0;
|
||
});
|
||
}
|
||
|
||
IOR_REG_SET (&deps->reg_last_in_use, reg_pending_uses);
|
||
IOR_REG_SET (&deps->reg_last_in_use, reg_pending_clobbers);
|
||
IOR_REG_SET (&deps->reg_last_in_use, reg_pending_sets);
|
||
}
|
||
CLEAR_REG_SET (reg_pending_uses);
|
||
CLEAR_REG_SET (reg_pending_clobbers);
|
||
CLEAR_REG_SET (reg_pending_sets);
|
||
|
||
/* If we are currently in a libcall scheduling group, then mark the
|
||
current insn as being in a scheduling group and that it can not
|
||
be moved into a different basic block. */
|
||
|
||
if (deps->libcall_block_tail_insn)
|
||
{
|
||
set_sched_group_p (insn);
|
||
CANT_MOVE (insn) = 1;
|
||
}
|
||
|
||
/* If a post-call group is still open, see if it should remain so.
|
||
This insn must be a simple move of a hard reg to a pseudo or
|
||
vice-versa.
|
||
|
||
We must avoid moving these insns for correctness on
|
||
SMALL_REGISTER_CLASS machines, and for special registers like
|
||
PIC_OFFSET_TABLE_REGNUM. For simplicity, extend this to all
|
||
hard regs for all targets. */
|
||
|
||
if (deps->in_post_call_group_p)
|
||
{
|
||
rtx tmp, set = single_set (insn);
|
||
int src_regno, dest_regno;
|
||
|
||
if (set == NULL)
|
||
goto end_call_group;
|
||
|
||
tmp = SET_DEST (set);
|
||
if (GET_CODE (tmp) == SUBREG)
|
||
tmp = SUBREG_REG (tmp);
|
||
if (GET_CODE (tmp) == REG)
|
||
dest_regno = REGNO (tmp);
|
||
else
|
||
goto end_call_group;
|
||
|
||
tmp = SET_SRC (set);
|
||
if (GET_CODE (tmp) == SUBREG)
|
||
tmp = SUBREG_REG (tmp);
|
||
if (GET_CODE (tmp) == REG)
|
||
src_regno = REGNO (tmp);
|
||
else
|
||
goto end_call_group;
|
||
|
||
if (src_regno < FIRST_PSEUDO_REGISTER
|
||
|| dest_regno < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
set_sched_group_p (insn);
|
||
CANT_MOVE (insn) = 1;
|
||
}
|
||
else
|
||
{
|
||
end_call_group:
|
||
deps->in_post_call_group_p = false;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Analyze every insn between HEAD and TAIL inclusive, creating LOG_LINKS
|
||
for every dependency. */
|
||
|
||
void
|
||
sched_analyze (deps, head, tail)
|
||
struct deps *deps;
|
||
rtx head, tail;
|
||
{
|
||
rtx insn;
|
||
rtx loop_notes = 0;
|
||
|
||
if (current_sched_info->use_cselib)
|
||
cselib_init ();
|
||
|
||
for (insn = head;; insn = NEXT_INSN (insn))
|
||
{
|
||
rtx link, end_seq, r0, set;
|
||
|
||
if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN)
|
||
{
|
||
/* Clear out the stale LOG_LINKS from flow. */
|
||
free_INSN_LIST_list (&LOG_LINKS (insn));
|
||
|
||
/* Make each JUMP_INSN a scheduling barrier for memory
|
||
references. */
|
||
if (GET_CODE (insn) == JUMP_INSN)
|
||
{
|
||
/* Keep the list a reasonable size. */
|
||
if (deps->pending_flush_length++ > MAX_PENDING_LIST_LENGTH)
|
||
flush_pending_lists (deps, insn, true, true);
|
||
else
|
||
deps->last_pending_memory_flush
|
||
= alloc_INSN_LIST (insn, deps->last_pending_memory_flush);
|
||
}
|
||
sched_analyze_insn (deps, PATTERN (insn), insn, loop_notes);
|
||
loop_notes = 0;
|
||
}
|
||
else if (GET_CODE (insn) == CALL_INSN)
|
||
{
|
||
int i;
|
||
|
||
CANT_MOVE (insn) = 1;
|
||
|
||
/* Clear out the stale LOG_LINKS from flow. */
|
||
free_INSN_LIST_list (&LOG_LINKS (insn));
|
||
|
||
if (find_reg_note (insn, REG_SETJMP, NULL))
|
||
{
|
||
/* This is setjmp. Assume that all registers, not just
|
||
hard registers, may be clobbered by this call. */
|
||
reg_pending_barrier = MOVE_BARRIER;
|
||
}
|
||
else
|
||
{
|
||
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
|
||
/* A call may read and modify global register variables. */
|
||
if (global_regs[i])
|
||
{
|
||
SET_REGNO_REG_SET (reg_pending_sets, i);
|
||
SET_REGNO_REG_SET (reg_pending_uses, i);
|
||
}
|
||
/* Other call-clobbered hard regs may be clobbered.
|
||
Since we only have a choice between 'might be clobbered'
|
||
and 'definitely not clobbered', we must include all
|
||
partly call-clobbered registers here. */
|
||
else if (HARD_REGNO_CALL_PART_CLOBBERED (i, reg_raw_mode[i])
|
||
|| TEST_HARD_REG_BIT (regs_invalidated_by_call, i))
|
||
SET_REGNO_REG_SET (reg_pending_clobbers, i);
|
||
/* We don't know what set of fixed registers might be used
|
||
by the function, but it is certain that the stack pointer
|
||
is among them, but be conservative. */
|
||
else if (fixed_regs[i])
|
||
SET_REGNO_REG_SET (reg_pending_uses, i);
|
||
/* The frame pointer is normally not used by the function
|
||
itself, but by the debugger. */
|
||
/* ??? MIPS o32 is an exception. It uses the frame pointer
|
||
in the macro expansion of jal but does not represent this
|
||
fact in the call_insn rtl. */
|
||
else if (i == FRAME_POINTER_REGNUM
|
||
|| (i == HARD_FRAME_POINTER_REGNUM
|
||
&& (! reload_completed || frame_pointer_needed)))
|
||
SET_REGNO_REG_SET (reg_pending_uses, i);
|
||
}
|
||
|
||
/* For each insn which shouldn't cross a call, add a dependence
|
||
between that insn and this call insn. */
|
||
add_dependence_list_and_free (insn, &deps->sched_before_next_call,
|
||
REG_DEP_ANTI);
|
||
|
||
sched_analyze_insn (deps, PATTERN (insn), insn, loop_notes);
|
||
loop_notes = 0;
|
||
|
||
/* In the absence of interprocedural alias analysis, we must flush
|
||
all pending reads and writes, and start new dependencies starting
|
||
from here. But only flush writes for constant calls (which may
|
||
be passed a pointer to something we haven't written yet). */
|
||
flush_pending_lists (deps, insn, true, !CONST_OR_PURE_CALL_P (insn));
|
||
|
||
/* Remember the last function call for limiting lifetimes. */
|
||
free_INSN_LIST_list (&deps->last_function_call);
|
||
deps->last_function_call = alloc_INSN_LIST (insn, NULL_RTX);
|
||
|
||
/* Before reload, begin a post-call group, so as to keep the
|
||
lifetimes of hard registers correct. */
|
||
if (! reload_completed)
|
||
deps->in_post_call_group_p = true;
|
||
}
|
||
|
||
/* See comments on reemit_notes as to why we do this.
|
||
??? Actually, the reemit_notes just say what is done, not why. */
|
||
|
||
if (GET_CODE (insn) == NOTE
|
||
&& (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG
|
||
|| NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END
|
||
|| NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_BEG
|
||
|| NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_END))
|
||
{
|
||
rtx rtx_region;
|
||
|
||
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_BEG
|
||
|| NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_END)
|
||
rtx_region = GEN_INT (NOTE_EH_HANDLER (insn));
|
||
else
|
||
rtx_region = GEN_INT (0);
|
||
|
||
loop_notes = alloc_EXPR_LIST (REG_SAVE_NOTE,
|
||
rtx_region,
|
||
loop_notes);
|
||
loop_notes = alloc_EXPR_LIST (REG_SAVE_NOTE,
|
||
GEN_INT (NOTE_LINE_NUMBER (insn)),
|
||
loop_notes);
|
||
CONST_OR_PURE_CALL_P (loop_notes) = CONST_OR_PURE_CALL_P (insn);
|
||
}
|
||
|
||
if (current_sched_info->use_cselib)
|
||
cselib_process_insn (insn);
|
||
|
||
/* Now that we have completed handling INSN, check and see if it is
|
||
a CLOBBER beginning a libcall block. If it is, record the
|
||
end of the libcall sequence.
|
||
|
||
We want to schedule libcall blocks as a unit before reload. While
|
||
this restricts scheduling, it preserves the meaning of a libcall
|
||
block.
|
||
|
||
As a side effect, we may get better code due to decreased register
|
||
pressure as well as less chance of a foreign insn appearing in
|
||
a libcall block. */
|
||
if (!reload_completed
|
||
/* Note we may have nested libcall sequences. We only care about
|
||
the outermost libcall sequence. */
|
||
&& deps->libcall_block_tail_insn == 0
|
||
/* The sequence must start with a clobber of a register. */
|
||
&& GET_CODE (insn) == INSN
|
||
&& GET_CODE (PATTERN (insn)) == CLOBBER
|
||
&& (r0 = XEXP (PATTERN (insn), 0), GET_CODE (r0) == REG)
|
||
&& GET_CODE (XEXP (PATTERN (insn), 0)) == REG
|
||
/* The CLOBBER must also have a REG_LIBCALL note attached. */
|
||
&& (link = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0
|
||
&& (end_seq = XEXP (link, 0)) != 0
|
||
/* The insn referenced by the REG_LIBCALL note must be a
|
||
simple nop copy with the same destination as the register
|
||
mentioned in the clobber. */
|
||
&& (set = single_set (end_seq)) != 0
|
||
&& SET_DEST (set) == r0 && SET_SRC (set) == r0
|
||
/* And finally the insn referenced by the REG_LIBCALL must
|
||
also contain a REG_EQUAL note and a REG_RETVAL note. */
|
||
&& find_reg_note (end_seq, REG_EQUAL, NULL_RTX) != 0
|
||
&& find_reg_note (end_seq, REG_RETVAL, NULL_RTX) != 0)
|
||
deps->libcall_block_tail_insn = XEXP (link, 0);
|
||
|
||
/* If we have reached the end of a libcall block, then close the
|
||
block. */
|
||
if (deps->libcall_block_tail_insn == insn)
|
||
deps->libcall_block_tail_insn = 0;
|
||
|
||
if (insn == tail)
|
||
{
|
||
if (current_sched_info->use_cselib)
|
||
cselib_finish ();
|
||
return;
|
||
}
|
||
}
|
||
abort ();
|
||
}
|
||
|
||
|
||
/* The following function adds forward dependence (FROM, TO) with
|
||
given DEP_TYPE. The forward dependence should be not exist before. */
|
||
|
||
void
|
||
add_forward_dependence (from, to, dep_type)
|
||
rtx from;
|
||
rtx to;
|
||
enum reg_note dep_type;
|
||
{
|
||
rtx new_link;
|
||
|
||
#ifdef ENABLE_CHECKING
|
||
/* If add_dependence is working properly there should never
|
||
be notes, deleted insns or duplicates in the backward
|
||
links. Thus we need not check for them here.
|
||
|
||
However, if we have enabled checking we might as well go
|
||
ahead and verify that add_dependence worked properly. */
|
||
if (GET_CODE (from) == NOTE
|
||
|| INSN_DELETED_P (from)
|
||
|| (forward_dependency_cache != NULL
|
||
&& TEST_BIT (forward_dependency_cache[INSN_LUID (from)],
|
||
INSN_LUID (to)))
|
||
|| (forward_dependency_cache == NULL
|
||
&& find_insn_list (to, INSN_DEPEND (from))))
|
||
abort ();
|
||
if (forward_dependency_cache != NULL)
|
||
SET_BIT (forward_dependency_cache[INSN_LUID (from)],
|
||
INSN_LUID (to));
|
||
#endif
|
||
|
||
new_link = alloc_INSN_LIST (to, INSN_DEPEND (from));
|
||
|
||
PUT_REG_NOTE_KIND (new_link, dep_type);
|
||
|
||
INSN_DEPEND (from) = new_link;
|
||
INSN_DEP_COUNT (to) += 1;
|
||
}
|
||
|
||
/* Examine insns in the range [ HEAD, TAIL ] and Use the backward
|
||
dependences from LOG_LINKS to build forward dependences in
|
||
INSN_DEPEND. */
|
||
|
||
void
|
||
compute_forward_dependences (head, tail)
|
||
rtx head, tail;
|
||
{
|
||
rtx insn, link;
|
||
rtx next_tail;
|
||
|
||
next_tail = NEXT_INSN (tail);
|
||
for (insn = head; insn != next_tail; insn = NEXT_INSN (insn))
|
||
{
|
||
if (! INSN_P (insn))
|
||
continue;
|
||
|
||
for (link = LOG_LINKS (insn); link; link = XEXP (link, 1))
|
||
add_forward_dependence (XEXP (link, 0), insn, REG_NOTE_KIND (link));
|
||
}
|
||
}
|
||
|
||
/* Initialize variables for region data dependence analysis.
|
||
n_bbs is the number of region blocks. */
|
||
|
||
void
|
||
init_deps (deps)
|
||
struct deps *deps;
|
||
{
|
||
int max_reg = (reload_completed ? FIRST_PSEUDO_REGISTER : max_reg_num ());
|
||
|
||
deps->max_reg = max_reg;
|
||
deps->reg_last = (struct deps_reg *)
|
||
xcalloc (max_reg, sizeof (struct deps_reg));
|
||
INIT_REG_SET (&deps->reg_last_in_use);
|
||
|
||
deps->pending_read_insns = 0;
|
||
deps->pending_read_mems = 0;
|
||
deps->pending_write_insns = 0;
|
||
deps->pending_write_mems = 0;
|
||
deps->pending_lists_length = 0;
|
||
deps->pending_flush_length = 0;
|
||
deps->last_pending_memory_flush = 0;
|
||
deps->last_function_call = 0;
|
||
deps->sched_before_next_call = 0;
|
||
deps->in_post_call_group_p = false;
|
||
deps->libcall_block_tail_insn = 0;
|
||
}
|
||
|
||
/* Free insn lists found in DEPS. */
|
||
|
||
void
|
||
free_deps (deps)
|
||
struct deps *deps;
|
||
{
|
||
int i;
|
||
|
||
free_INSN_LIST_list (&deps->pending_read_insns);
|
||
free_EXPR_LIST_list (&deps->pending_read_mems);
|
||
free_INSN_LIST_list (&deps->pending_write_insns);
|
||
free_EXPR_LIST_list (&deps->pending_write_mems);
|
||
free_INSN_LIST_list (&deps->last_pending_memory_flush);
|
||
|
||
/* Without the EXECUTE_IF_SET, this loop is executed max_reg * nr_regions
|
||
times. For a test case with 42000 regs and 8000 small basic blocks,
|
||
this loop accounted for nearly 60% (84 sec) of the total -O2 runtime. */
|
||
EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i,
|
||
{
|
||
struct deps_reg *reg_last = &deps->reg_last[i];
|
||
if (reg_last->uses)
|
||
free_INSN_LIST_list (®_last->uses);
|
||
if (reg_last->sets)
|
||
free_INSN_LIST_list (®_last->sets);
|
||
if (reg_last->clobbers)
|
||
free_INSN_LIST_list (®_last->clobbers);
|
||
});
|
||
CLEAR_REG_SET (&deps->reg_last_in_use);
|
||
|
||
free (deps->reg_last);
|
||
}
|
||
|
||
/* If it is profitable to use them, initialize caches for tracking
|
||
dependency information. LUID is the number of insns to be scheduled,
|
||
it is used in the estimate of profitability. */
|
||
|
||
void
|
||
init_dependency_caches (luid)
|
||
int luid;
|
||
{
|
||
/* ?!? We could save some memory by computing a per-region luid mapping
|
||
which could reduce both the number of vectors in the cache and the size
|
||
of each vector. Instead we just avoid the cache entirely unless the
|
||
average number of instructions in a basic block is very high. See
|
||
the comment before the declaration of true_dependency_cache for
|
||
what we consider "very high". */
|
||
if (luid / n_basic_blocks > 100 * 5)
|
||
{
|
||
true_dependency_cache = sbitmap_vector_alloc (luid, luid);
|
||
sbitmap_vector_zero (true_dependency_cache, luid);
|
||
anti_dependency_cache = sbitmap_vector_alloc (luid, luid);
|
||
sbitmap_vector_zero (anti_dependency_cache, luid);
|
||
output_dependency_cache = sbitmap_vector_alloc (luid, luid);
|
||
sbitmap_vector_zero (output_dependency_cache, luid);
|
||
#ifdef ENABLE_CHECKING
|
||
forward_dependency_cache = sbitmap_vector_alloc (luid, luid);
|
||
sbitmap_vector_zero (forward_dependency_cache, luid);
|
||
#endif
|
||
}
|
||
}
|
||
|
||
/* Free the caches allocated in init_dependency_caches. */
|
||
|
||
void
|
||
free_dependency_caches ()
|
||
{
|
||
if (true_dependency_cache)
|
||
{
|
||
sbitmap_vector_free (true_dependency_cache);
|
||
true_dependency_cache = NULL;
|
||
sbitmap_vector_free (anti_dependency_cache);
|
||
anti_dependency_cache = NULL;
|
||
sbitmap_vector_free (output_dependency_cache);
|
||
output_dependency_cache = NULL;
|
||
#ifdef ENABLE_CHECKING
|
||
sbitmap_vector_free (forward_dependency_cache);
|
||
forward_dependency_cache = NULL;
|
||
#endif
|
||
}
|
||
}
|
||
|
||
/* Initialize some global variables needed by the dependency analysis
|
||
code. */
|
||
|
||
void
|
||
init_deps_global ()
|
||
{
|
||
reg_pending_sets = INITIALIZE_REG_SET (reg_pending_sets_head);
|
||
reg_pending_clobbers = INITIALIZE_REG_SET (reg_pending_clobbers_head);
|
||
reg_pending_uses = INITIALIZE_REG_SET (reg_pending_uses_head);
|
||
reg_pending_barrier = NOT_A_BARRIER;
|
||
}
|
||
|
||
/* Free everything used by the dependency analysis code. */
|
||
|
||
void
|
||
finish_deps_global ()
|
||
{
|
||
FREE_REG_SET (reg_pending_sets);
|
||
FREE_REG_SET (reg_pending_clobbers);
|
||
FREE_REG_SET (reg_pending_uses);
|
||
}
|