/* Perform various loop optimizations, including strength reduction.
Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
- 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
+ 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of GCC.
/* This is the loop optimization pass of the compiler.
It finds invariant computations within loops and moves them
to the beginning of the loop. Then it identifies basic and
- general induction variables. Strength reduction is applied to the general
- induction variables, and induction variable elimination is applied to
+ general induction variables.
+
+ Basic induction variables (BIVs) are a pseudo registers which are set within
+ a loop only by incrementing or decrementing its value. General induction
+ variables (GIVs) are pseudo registers with a value which is a linear function
+ of a basic induction variable. BIVs are recognized by `basic_induction_var';
+ GIVs by `general_induction_var'.
+
+ Once induction variables are identified, strength reduction is applied to the
+ general induction variables, and induction variable elimination is applied to
the basic induction variables.
It also finds cases where
#include "predict.h"
#include "insn-flags.h"
#include "optabs.h"
+#include "cfgloop.h"
+#include "ggc.h"
/* Not really meaningful values, but at least something. */
#ifndef SIMULTANEOUS_PREFETCHES
#define gen_prefetch(a,b,c) (abort(), NULL_RTX)
#endif
-/* Give up the prefetch optimizations once we exceed a given threshhold.
+/* Give up the prefetch optimizations once we exceed a given threshold.
It is unlikely that we would be able to optimize something in a loop
with so many detected prefetches. */
#define MAX_PREFETCHES 100
#define PREFETCH_BLOCKS_BEFORE_LOOP_MIN 2
/* Parameterize some prefetch heuristics so they can be turned on and off
- easily for performance testing on new architecures. These can be
+ easily for performance testing on new architectures. These can be
defined in target-dependent files. */
/* Prefetch is worthwhile only when loads/stores are dense. */
#define LOOP_REGNO_NREGS(REGNO, SET_DEST) \
((REGNO) < FIRST_PSEUDO_REGISTER \
- ? (int) HARD_REGNO_NREGS ((REGNO), GET_MODE (SET_DEST)) : 1)
+ ? (int) hard_regno_nregs[(REGNO)][GET_MODE (SET_DEST)] : 1)
/* Vector mapping INSN_UIDs to luids.
short savings; /* Number of insns we can move for this reg,
including other movables that force this
or match this one. */
+ ENUM_BITFIELD(machine_mode) savemode : 8; /* Nonzero means it is a mode for
+ a low part that we should avoid changing when
+ clearing the rest of the reg. */
unsigned int cond : 1; /* 1 if only conditionally movable */
unsigned int force : 1; /* 1 means MUST move this insn */
unsigned int global : 1; /* 1 means reg is live outside this loop */
unsigned int move_insn_first:1;/* Same as above, if this is necessary for the
first insn of a consecutive sets group. */
unsigned int is_equiv : 1; /* 1 means a REG_EQUIV is present on INSN. */
- enum machine_mode savemode; /* Nonzero means it is a mode for a low part
- that we should avoid changing when clearing
- the rest of the reg. */
+ unsigned int insert_temp : 1; /* 1 means we copy to a new pseudo and replace
+ the original insn with a copy from that
+ pseudo, rather than deleting it. */
struct movable *match; /* First entry for same value */
struct movable *forces; /* An insn that must be moved if this is */
struct movable *next;
/* Forward declarations. */
-static void invalidate_loops_containing_label PARAMS ((rtx));
-static void find_and_verify_loops PARAMS ((rtx, struct loops *));
-static void mark_loop_jump PARAMS ((rtx, struct loop *));
-static void prescan_loop PARAMS ((struct loop *));
-static int reg_in_basic_block_p PARAMS ((rtx, rtx));
-static int consec_sets_invariant_p PARAMS ((const struct loop *,
- rtx, int, rtx));
-static int labels_in_range_p PARAMS ((rtx, int));
-static void count_one_set PARAMS ((struct loop_regs *, rtx, rtx, rtx *));
-static void note_addr_stored PARAMS ((rtx, rtx, void *));
-static void note_set_pseudo_multiple_uses PARAMS ((rtx, rtx, void *));
-static int loop_reg_used_before_p PARAMS ((const struct loop *, rtx, rtx));
-static void scan_loop PARAMS ((struct loop*, int));
+static void invalidate_loops_containing_label (rtx);
+static void find_and_verify_loops (rtx, struct loops *);
+static void mark_loop_jump (rtx, struct loop *);
+static void prescan_loop (struct loop *);
+static int reg_in_basic_block_p (rtx, rtx);
+static int consec_sets_invariant_p (const struct loop *, rtx, int, rtx);
+static int labels_in_range_p (rtx, int);
+static void count_one_set (struct loop_regs *, rtx, rtx, rtx *);
+static void note_addr_stored (rtx, rtx, void *);
+static void note_set_pseudo_multiple_uses (rtx, rtx, void *);
+static int loop_reg_used_before_p (const struct loop *, rtx, rtx);
+static rtx find_regs_nested (rtx, rtx);
+static void scan_loop (struct loop*, int);
#if 0
-static void replace_call_address PARAMS ((rtx, rtx, rtx));
+static void replace_call_address (rtx, rtx, rtx);
#endif
-static rtx skip_consec_insns PARAMS ((rtx, int));
-static int libcall_benefit PARAMS ((rtx));
-static void ignore_some_movables PARAMS ((struct loop_movables *));
-static void force_movables PARAMS ((struct loop_movables *));
-static void combine_movables PARAMS ((struct loop_movables *,
- struct loop_regs *));
-static int num_unmoved_movables PARAMS ((const struct loop *));
-static int regs_match_p PARAMS ((rtx, rtx, struct loop_movables *));
-static int rtx_equal_for_loop_p PARAMS ((rtx, rtx, struct loop_movables *,
- struct loop_regs *));
-static void add_label_notes PARAMS ((rtx, rtx));
-static void move_movables PARAMS ((struct loop *loop, struct loop_movables *,
- int, int));
-static void loop_movables_add PARAMS((struct loop_movables *,
- struct movable *));
-static void loop_movables_free PARAMS((struct loop_movables *));
-static int count_nonfixed_reads PARAMS ((const struct loop *, rtx));
-static void loop_bivs_find PARAMS((struct loop *));
-static void loop_bivs_init_find PARAMS((struct loop *));
-static void loop_bivs_check PARAMS((struct loop *));
-static void loop_givs_find PARAMS((struct loop *));
-static void loop_givs_check PARAMS((struct loop *));
-static int loop_biv_eliminable_p PARAMS((struct loop *, struct iv_class *,
- int, int));
-static int loop_giv_reduce_benefit PARAMS((struct loop *, struct iv_class *,
- struct induction *, rtx));
-static void loop_givs_dead_check PARAMS((struct loop *, struct iv_class *));
-static void loop_givs_reduce PARAMS((struct loop *, struct iv_class *));
-static void loop_givs_rescan PARAMS((struct loop *, struct iv_class *,
- rtx *));
-static void loop_ivs_free PARAMS((struct loop *));
-static void strength_reduce PARAMS ((struct loop *, int));
-static void find_single_use_in_loop PARAMS ((struct loop_regs *, rtx, rtx));
-static int valid_initial_value_p PARAMS ((rtx, rtx, int, rtx));
-static void find_mem_givs PARAMS ((const struct loop *, rtx, rtx, int, int));
-static void record_biv PARAMS ((struct loop *, struct induction *,
- rtx, rtx, rtx, rtx, rtx *,
- int, int));
-static void check_final_value PARAMS ((const struct loop *,
- struct induction *));
-static void loop_ivs_dump PARAMS((const struct loop *, FILE *, int));
-static void loop_iv_class_dump PARAMS((const struct iv_class *, FILE *, int));
-static void loop_biv_dump PARAMS((const struct induction *, FILE *, int));
-static void loop_giv_dump PARAMS((const struct induction *, FILE *, int));
-static void record_giv PARAMS ((const struct loop *, struct induction *,
- rtx, rtx, rtx, rtx, rtx, rtx, int,
- enum g_types, int, int, rtx *));
-static void update_giv_derive PARAMS ((const struct loop *, rtx));
-static void check_ext_dependent_givs PARAMS ((struct iv_class *,
- struct loop_info *));
-static int basic_induction_var PARAMS ((const struct loop *, rtx,
- enum machine_mode, rtx, rtx,
- rtx *, rtx *, rtx **));
-static rtx simplify_giv_expr PARAMS ((const struct loop *, rtx, rtx *, int *));
-static int general_induction_var PARAMS ((const struct loop *loop, rtx, rtx *,
- rtx *, rtx *, rtx *, int, int *,
- enum machine_mode));
-static int consec_sets_giv PARAMS ((const struct loop *, int, rtx,
- rtx, rtx, rtx *, rtx *, rtx *, rtx *));
-static int check_dbra_loop PARAMS ((struct loop *, int));
-static rtx express_from_1 PARAMS ((rtx, rtx, rtx));
-static rtx combine_givs_p PARAMS ((struct induction *, struct induction *));
-static int cmp_combine_givs_stats PARAMS ((const PTR, const PTR));
-static void combine_givs PARAMS ((struct loop_regs *, struct iv_class *));
-static int product_cheap_p PARAMS ((rtx, rtx));
-static int maybe_eliminate_biv PARAMS ((const struct loop *, struct iv_class *,
- int, int, int));
-static int maybe_eliminate_biv_1 PARAMS ((const struct loop *, rtx, rtx,
- struct iv_class *, int,
- basic_block, rtx));
-static int last_use_this_basic_block PARAMS ((rtx, rtx));
-static void record_initial PARAMS ((rtx, rtx, void *));
-static void update_reg_last_use PARAMS ((rtx, rtx));
-static rtx next_insn_in_loop PARAMS ((const struct loop *, rtx));
-static void loop_regs_scan PARAMS ((const struct loop *, int));
-static int count_insns_in_loop PARAMS ((const struct loop *));
-static void load_mems PARAMS ((const struct loop *));
-static int insert_loop_mem PARAMS ((rtx *, void *));
-static int replace_loop_mem PARAMS ((rtx *, void *));
-static void replace_loop_mems PARAMS ((rtx, rtx, rtx));
-static int replace_loop_reg PARAMS ((rtx *, void *));
-static void replace_loop_regs PARAMS ((rtx insn, rtx, rtx));
-static void note_reg_stored PARAMS ((rtx, rtx, void *));
-static void try_copy_prop PARAMS ((const struct loop *, rtx, unsigned int));
-static void try_swap_copy_prop PARAMS ((const struct loop *, rtx,
- unsigned int));
-static int replace_label PARAMS ((rtx *, void *));
-static rtx check_insn_for_givs PARAMS((struct loop *, rtx, int, int));
-static rtx check_insn_for_bivs PARAMS((struct loop *, rtx, int, int));
-static rtx gen_add_mult PARAMS ((rtx, rtx, rtx, rtx));
-static void loop_regs_update PARAMS ((const struct loop *, rtx));
-static int iv_add_mult_cost PARAMS ((rtx, rtx, rtx, rtx));
-
-static rtx loop_insn_emit_after PARAMS((const struct loop *, basic_block,
- rtx, rtx));
-static rtx loop_call_insn_emit_before PARAMS((const struct loop *,
- basic_block, rtx, rtx));
-static rtx loop_call_insn_hoist PARAMS((const struct loop *, rtx));
-static rtx loop_insn_sink_or_swim PARAMS((const struct loop *, rtx));
-
-static void loop_dump_aux PARAMS ((const struct loop *, FILE *, int));
-static void loop_delete_insns PARAMS ((rtx, rtx));
-static HOST_WIDE_INT remove_constant_addition PARAMS ((rtx *));
-static rtx gen_load_of_final_value PARAMS ((rtx, rtx));
-void debug_ivs PARAMS ((const struct loop *));
-void debug_iv_class PARAMS ((const struct iv_class *));
-void debug_biv PARAMS ((const struct induction *));
-void debug_giv PARAMS ((const struct induction *));
-void debug_loop PARAMS ((const struct loop *));
-void debug_loops PARAMS ((const struct loops *));
-
-typedef struct rtx_pair
-{
- rtx r1;
- rtx r2;
-} rtx_pair;
+static rtx skip_consec_insns (rtx, int);
+static int libcall_benefit (rtx);
+static rtx libcall_other_reg (rtx, rtx);
+static void record_excess_regs (rtx, rtx, rtx *);
+static void ignore_some_movables (struct loop_movables *);
+static void force_movables (struct loop_movables *);
+static void combine_movables (struct loop_movables *, struct loop_regs *);
+static int num_unmoved_movables (const struct loop *);
+static int regs_match_p (rtx, rtx, struct loop_movables *);
+static int rtx_equal_for_loop_p (rtx, rtx, struct loop_movables *,
+ struct loop_regs *);
+static void add_label_notes (rtx, rtx);
+static void move_movables (struct loop *loop, struct loop_movables *, int,
+ int);
+static void loop_movables_add (struct loop_movables *, struct movable *);
+static void loop_movables_free (struct loop_movables *);
+static int count_nonfixed_reads (const struct loop *, rtx);
+static void loop_bivs_find (struct loop *);
+static void loop_bivs_init_find (struct loop *);
+static void loop_bivs_check (struct loop *);
+static void loop_givs_find (struct loop *);
+static void loop_givs_check (struct loop *);
+static int loop_biv_eliminable_p (struct loop *, struct iv_class *, int, int);
+static int loop_giv_reduce_benefit (struct loop *, struct iv_class *,
+ struct induction *, rtx);
+static void loop_givs_dead_check (struct loop *, struct iv_class *);
+static void loop_givs_reduce (struct loop *, struct iv_class *);
+static void loop_givs_rescan (struct loop *, struct iv_class *, rtx *);
+static void loop_ivs_free (struct loop *);
+static void strength_reduce (struct loop *, int);
+static void find_single_use_in_loop (struct loop_regs *, rtx, rtx);
+static int valid_initial_value_p (rtx, rtx, int, rtx);
+static void find_mem_givs (const struct loop *, rtx, rtx, int, int);
+static void record_biv (struct loop *, struct induction *, rtx, rtx, rtx,
+ rtx, rtx *, int, int);
+static void check_final_value (const struct loop *, struct induction *);
+static void loop_ivs_dump (const struct loop *, FILE *, int);
+static void loop_iv_class_dump (const struct iv_class *, FILE *, int);
+static void loop_biv_dump (const struct induction *, FILE *, int);
+static void loop_giv_dump (const struct induction *, FILE *, int);
+static void record_giv (const struct loop *, struct induction *, rtx, rtx,
+ rtx, rtx, rtx, rtx, int, enum g_types, int, int,
+ rtx *);
+static void update_giv_derive (const struct loop *, rtx);
+static void check_ext_dependent_givs (const struct loop *, struct iv_class *);
+static int basic_induction_var (const struct loop *, rtx, enum machine_mode,
+ rtx, rtx, rtx *, rtx *, rtx **);
+static rtx simplify_giv_expr (const struct loop *, rtx, rtx *, int *);
+static int general_induction_var (const struct loop *loop, rtx, rtx *, rtx *,
+ rtx *, rtx *, int, int *, enum machine_mode);
+static int consec_sets_giv (const struct loop *, int, rtx, rtx, rtx, rtx *,
+ rtx *, rtx *, rtx *);
+static int check_dbra_loop (struct loop *, int);
+static rtx express_from_1 (rtx, rtx, rtx);
+static rtx combine_givs_p (struct induction *, struct induction *);
+static int cmp_combine_givs_stats (const void *, const void *);
+static void combine_givs (struct loop_regs *, struct iv_class *);
+static int product_cheap_p (rtx, rtx);
+static int maybe_eliminate_biv (const struct loop *, struct iv_class *, int,
+ int, int);
+static int maybe_eliminate_biv_1 (const struct loop *, rtx, rtx,
+ struct iv_class *, int, basic_block, rtx);
+static int last_use_this_basic_block (rtx, rtx);
+static void record_initial (rtx, rtx, void *);
+static void update_reg_last_use (rtx, rtx);
+static rtx next_insn_in_loop (const struct loop *, rtx);
+static void loop_regs_scan (const struct loop *, int);
+static int count_insns_in_loop (const struct loop *);
+static int find_mem_in_note_1 (rtx *, void *);
+static rtx find_mem_in_note (rtx);
+static void load_mems (const struct loop *);
+static int insert_loop_mem (rtx *, void *);
+static int replace_loop_mem (rtx *, void *);
+static void replace_loop_mems (rtx, rtx, rtx, int);
+static int replace_loop_reg (rtx *, void *);
+static void replace_loop_regs (rtx insn, rtx, rtx);
+static void note_reg_stored (rtx, rtx, void *);
+static void try_copy_prop (const struct loop *, rtx, unsigned int);
+static void try_swap_copy_prop (const struct loop *, rtx, unsigned int);
+static rtx check_insn_for_givs (struct loop *, rtx, int, int);
+static rtx check_insn_for_bivs (struct loop *, rtx, int, int);
+static rtx gen_add_mult (rtx, rtx, rtx, rtx);
+static void loop_regs_update (const struct loop *, rtx);
+static int iv_add_mult_cost (rtx, rtx, rtx, rtx);
+
+static rtx loop_insn_emit_after (const struct loop *, basic_block, rtx, rtx);
+static rtx loop_call_insn_emit_before (const struct loop *, basic_block,
+ rtx, rtx);
+static rtx loop_call_insn_hoist (const struct loop *, rtx);
+static rtx loop_insn_sink_or_swim (const struct loop *, rtx);
+
+static void loop_dump_aux (const struct loop *, FILE *, int);
+static void loop_delete_insns (rtx, rtx);
+static HOST_WIDE_INT remove_constant_addition (rtx *);
+static rtx gen_load_of_final_value (rtx, rtx);
+void debug_ivs (const struct loop *);
+void debug_iv_class (const struct iv_class *);
+void debug_biv (const struct induction *);
+void debug_giv (const struct induction *);
+void debug_loop (const struct loop *);
+void debug_loops (const struct loops *);
typedef struct loop_replace_args
{
/* Indirect_jump_in_function is computed once per function. */
static int indirect_jump_in_function;
-static int indirect_jump_in_function_p PARAMS ((rtx));
+static int indirect_jump_in_function_p (rtx);
-static int compute_luids PARAMS ((rtx, rtx, int));
+static int compute_luids (rtx, rtx, int);
-static int biv_elimination_giv_has_0_offset PARAMS ((struct induction *,
- struct induction *,
- rtx));
+static int biv_elimination_giv_has_0_offset (struct induction *,
+ struct induction *, rtx);
\f
/* Benefit penalty, if a giv is not replaceable, i.e. must emit an insn to
copy the value of the strength reduced giv to its original register. */
static int reg_address_cost;
void
-init_loop ()
+init_loop (void)
{
rtx reg = gen_rtx_REG (word_mode, LAST_VIRTUAL_REGISTER + 1);
Start at insn START and stop just before END. Assign LUIDs
starting with PREV_LUID + 1. Return the last assigned LUID + 1. */
static int
-compute_luids (start, end, prev_luid)
- rtx start, end;
- int prev_luid;
+compute_luids (rtx start, rtx end, int prev_luid)
{
int i;
rtx insn;
(or 0 if none should be output). */
void
-loop_optimize (f, dumpfile, flags)
- /* f is the first instruction of a chain of insns for one function */
- rtx f;
- FILE *dumpfile;
- int flags;
+loop_optimize (rtx f, FILE *dumpfile, int flags)
{
rtx insn;
int i;
Leave some space for labels allocated by find_and_verify_loops. */
max_uid_for_loop = get_max_uid () + 1 + max_loop_num * 32;
- uid_luid = (int *) xcalloc (max_uid_for_loop, sizeof (int));
- uid_loop = (struct loop **) xcalloc (max_uid_for_loop,
- sizeof (struct loop *));
+ uid_luid = xcalloc (max_uid_for_loop, sizeof (int));
+ uid_loop = xcalloc (max_uid_for_loop, sizeof (struct loop *));
/* Allocate storage for array of loops. */
- loops->array = (struct loop *)
- xcalloc (loops->num, sizeof (struct loop));
+ loops->array = xcalloc (loops->num, sizeof (struct loop));
/* Find and process each loop.
First, find them, and record them in order of their beginnings. */
/* Allocate and initialize auxiliary loop information. */
loops_info = xcalloc (loops->num, sizeof (struct loop_info));
- for (i = 0; i < loops->num; i++)
+ for (i = 0; i < (int) loops->num; i++)
loops->array[i].aux = loops_info + i;
/* Now find all register lifetimes. This must be done after
struct loop *loop = &loops->array[i];
if (! loop->invalid && loop->end)
- scan_loop (loop, flags);
+ {
+ scan_loop (loop, flags);
+ ggc_collect ();
+ }
}
end_alias_analysis ();
/* Clean up. */
+ for (i = 0; i < (int) loops->num; i++)
+ free (loops_info[i].mems);
+
free (uid_luid);
free (uid_loop);
free (loops_info);
bottom. */
static rtx
-next_insn_in_loop (loop, insn)
- const struct loop *loop;
- rtx insn;
+next_insn_in_loop (const struct loop *loop, rtx insn)
{
insn = NEXT_INSN (insn);
return insn;
}
+/* Find any register references hidden inside X and add them to
+ the dependency list DEPS. This is used to look inside CLOBBER (MEM
+ when checking whether a PARALLEL can be pulled out of a loop. */
+
+static rtx
+find_regs_nested (rtx deps, rtx x)
+{
+ enum rtx_code code = GET_CODE (x);
+ if (code == REG)
+ deps = gen_rtx_EXPR_LIST (VOIDmode, x, deps);
+ else
+ {
+ const char *fmt = GET_RTX_FORMAT (code);
+ int i, j;
+ for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
+ {
+ if (fmt[i] == 'e')
+ deps = find_regs_nested (deps, XEXP (x, i));
+ else if (fmt[i] == 'E')
+ for (j = 0; j < XVECLEN (x, i); j++)
+ deps = find_regs_nested (deps, XVECEXP (x, i, j));
+ }
+ }
+ return deps;
+}
+
/* Optimize one loop described by LOOP. */
/* ??? Could also move memory writes out of loops if the destination address
write, then we can also mark the memory read as invariant. */
static void
-scan_loop (loop, flags)
- struct loop *loop;
- int flags;
+scan_loop (struct loop *loop, int flags)
{
struct loop_info *loop_info = LOOP_INFO (loop);
struct loop_regs *regs = LOOP_REGS (loop);
int tem1 = 0;
int tem2 = 0;
int move_insn = 0;
+ int insert_temp = 0;
rtx src = SET_SRC (set);
rtx dependencies = 0;
}
}
- /* For parallels, add any possible uses to the depencies, as
- we can't move the insn without resolving them first. */
+ /* For parallels, add any possible uses to the dependencies, as
+ we can't move the insn without resolving them first.
+ MEMs inside CLOBBERs may also reference registers; these
+ count as implicit uses. */
if (GET_CODE (PATTERN (p)) == PARALLEL)
{
for (i = 0; i < XVECLEN (PATTERN (p), 0); i++)
dependencies
= gen_rtx_EXPR_LIST (VOIDmode, XEXP (x, 0),
dependencies);
+ else if (GET_CODE (x) == CLOBBER
+ && GET_CODE (XEXP (x, 0)) == MEM)
+ dependencies = find_regs_nested (dependencies,
+ XEXP (XEXP (x, 0), 0));
}
}
- /* Don't try to optimize a register that was made
- by loop-optimization for an inner loop.
- We don't know its life-span, so we can't compute
- the benefit. */
- if (REGNO (SET_DEST (set)) >= max_reg_before_loop)
- ;
- else if (/* The register is used in basic blocks other
- than the one where it is set (meaning that
- something after this point in the loop might
- depend on its value before the set). */
- ! reg_in_basic_block_p (p, SET_DEST (set))
- /* And the set is not guaranteed to be executed once
- the loop starts, or the value before the set is
- needed before the set occurs...
-
- ??? Note we have quadratic behavior here, mitigated
- by the fact that the previous test will often fail for
- large loops. Rather than re-scanning the entire loop
- each time for register usage, we should build tables
- of the register usage and use them here instead. */
- && (maybe_never
- || loop_reg_used_before_p (loop, set, p)))
- /* It is unsafe to move the set.
+ if (/* The register is used in basic blocks other
+ than the one where it is set (meaning that
+ something after this point in the loop might
+ depend on its value before the set). */
+ ! reg_in_basic_block_p (p, SET_DEST (set))
+ /* And the set is not guaranteed to be executed once
+ the loop starts, or the value before the set is
+ needed before the set occurs...
+
+ ??? Note we have quadratic behavior here, mitigated
+ by the fact that the previous test will often fail for
+ large loops. Rather than re-scanning the entire loop
+ each time for register usage, we should build tables
+ of the register usage and use them here instead. */
+ && (maybe_never
+ || loop_reg_used_before_p (loop, set, p)))
+ /* It is unsafe to move the set. However, it may be OK to
+ move the source into a new pseudo, and substitute a
+ reg-to-reg copy for the original insn.
This code used to consider it OK to move a set of a variable
which was not created by the user and not used in an exit
test.
That behavior is incorrect and was removed. */
+ insert_temp = 1;
+
+ /* Don't try to optimize a MODE_CC set with a constant
+ source. It probably will be combined with a conditional
+ jump. */
+ if (GET_MODE_CLASS (GET_MODE (SET_DEST (set))) == MODE_CC
+ && CONSTANT_P (src))
+ ;
+ /* Don't try to optimize a register that was made
+ by loop-optimization for an inner loop.
+ We don't know its life-span, so we can't compute
+ the benefit. */
+ else if (REGNO (SET_DEST (set)) >= max_reg_before_loop)
+ ;
+ /* Don't move the source and add a reg-to-reg copy:
+ - with -Os (this certainly increases size),
+ - if the mode doesn't support copy operations (obviously),
+ - if the source is already a reg (the motion will gain nothing),
+ - if the source is a legitimate constant (likewise). */
+ else if (insert_temp
+ && (optimize_size
+ || ! can_copy_p (GET_MODE (SET_SRC (set)))
+ || GET_CODE (SET_SRC (set)) == REG
+ || (CONSTANT_P (SET_SRC (set))
+ && LEGITIMATE_CONSTANT_P (SET_SRC (set)))))
;
else if ((tem = loop_invariant_p (loop, src))
&& (dependencies == 0
continue;
}
- m = (struct movable *) xmalloc (sizeof (struct movable));
+ m = xmalloc (sizeof (struct movable));
m->next = 0;
m->insn = p;
m->set_src = src;
m->partial = 0;
m->move_insn = move_insn;
m->move_insn_first = 0;
+ m->insert_temp = insert_temp;
m->is_equiv = (find_reg_note (p, REG_EQUIV, NULL_RTX) != 0);
m->savemode = VOIDmode;
m->regno = regno;
if (regs->array[regno].set_in_loop == 2)
{
struct movable *m;
- m = (struct movable *) xmalloc (sizeof (struct movable));
+ m = xmalloc (sizeof (struct movable));
m->next = 0;
m->insn = p;
m->set_dest = SET_DEST (set);
m->forces = 0;
m->move_insn = 0;
m->move_insn_first = 0;
+ m->insert_temp = insert_temp;
m->partial = 1;
/* If the insn may not be executed on some cycles,
we can't clear the whole reg; clear just high part.
/* Now consider each movable insn to decide whether it is worth moving.
Store 0 in regs->array[I].set_in_loop for each reg I that is moved.
- Generally this increases code size, so do not move moveables when
- optimizing for code size. */
+ For machines with few registers this increases code size, so do not
+ move moveables when optimizing for code size on such machines.
+ (The 18 below is the value for i386.) */
- if (! optimize_size)
+ if (!optimize_size
+ || (reg_class_size[GENERAL_REGS] > 18 && !loop_info->has_call))
{
move_movables (loop, movables, threshold, insn_count);
/* Add elements to *OUTPUT to record all the pseudo-regs
mentioned in IN_THIS but not mentioned in NOT_IN_THIS. */
-void
-record_excess_regs (in_this, not_in_this, output)
- rtx in_this, not_in_this;
- rtx *output;
+static void
+record_excess_regs (rtx in_this, rtx not_in_this, rtx *output)
{
enum rtx_code code;
const char *fmt;
If there are none, return 0.
If there are one or more, return an EXPR_LIST containing all of them. */
-rtx
-libcall_other_reg (insn, equiv)
- rtx insn, equiv;
+static rtx
+libcall_other_reg (rtx insn, rtx equiv)
{
rtx note = find_reg_note (insn, REG_RETVAL, NULL_RTX);
rtx p = XEXP (note, 0);
are between INSN and the end of the basic block. */
static int
-reg_in_basic_block_p (insn, reg)
- rtx insn, reg;
+reg_in_basic_block_p (rtx insn, rtx reg)
{
int regno = REGNO (reg);
rtx p;
value directly or can contain a library call. */
static int
-libcall_benefit (last)
- rtx last;
+libcall_benefit (rtx last)
{
rtx insn;
int benefit = 0;
/* Skip COUNT insns from INSN, counting library calls as 1 insn. */
static rtx
-skip_consec_insns (insn, count)
- rtx insn;
- int count;
+skip_consec_insns (rtx insn, int count)
{
for (; count > 0; count--)
{
was made later and so appears later on the chain. */
static void
-ignore_some_movables (movables)
- struct loop_movables *movables;
+ignore_some_movables (struct loop_movables *movables)
{
struct movable *m, *m1;
since the second can be moved only if the first is. */
static void
-force_movables (movables)
- struct loop_movables *movables;
+force_movables (struct loop_movables *movables)
{
struct movable *m, *m1;
m = 0;
/* Increase the priority of the moving the first insn
- since it permits the second to be moved as well. */
+ since it permits the second to be moved as well.
+ Likewise for insns already forced by the first insn. */
if (m != 0)
{
+ struct movable *m2;
+
m->forces = m1;
- m1->lifetime += m->lifetime;
- m1->savings += m->savings;
+ for (m2 = m1; m2; m2 = m2->forces)
+ {
+ m2->lifetime += m->lifetime;
+ m2->savings += m->savings;
+ }
}
}
}
one register. */
static void
-combine_movables (movables, regs)
- struct loop_movables *movables;
- struct loop_regs *regs;
+combine_movables (struct loop_movables *movables, struct loop_regs *regs)
{
struct movable *m;
- char *matched_regs = (char *) xmalloc (regs->num);
+ char *matched_regs = xmalloc (regs->num);
enum machine_mode mode;
/* Regs that are set more than once are not allowed to match
for (m = movables->head; m; m = m->next)
if (m->match == 0 && regs->array[m->regno].n_times_set == 1
&& m->regno >= FIRST_PSEUDO_REGISTER
+ && !m->insert_temp
&& !m->partial)
{
struct movable *m1;
one match any later ones. So start this loop at m->next. */
for (m1 = m->next; m1; m1 = m1->next)
if (m != m1 && m1->match == 0
+ && !m1->insert_temp
&& regs->array[m1->regno].n_times_set == 1
&& m1->regno >= FIRST_PSEUDO_REGISTER
/* A reg used outside the loop mustn't be eliminated. */
moved outside the loop. */
static int
-num_unmoved_movables (loop)
- const struct loop *loop;
+num_unmoved_movables (const struct loop *loop)
{
int num = 0;
struct movable *m;
/* Return 1 if regs X and Y will become the same if moved. */
static int
-regs_match_p (x, y, movables)
- rtx x, y;
- struct loop_movables *movables;
+regs_match_p (rtx x, rtx y, struct loop_movables *movables)
{
unsigned int xn = REGNO (x);
unsigned int yn = REGNO (y);
equivalent constant, consider them equal. */
static int
-rtx_equal_for_loop_p (x, y, movables, regs)
- rtx x, y;
- struct loop_movables *movables;
- struct loop_regs *regs;
+rtx_equal_for_loop_p (rtx x, rtx y, struct loop_movables *movables,
+ struct loop_regs *regs)
{
int i;
int j;
references is incremented once for each added note. */
static void
-add_label_notes (x, insns)
- rtx x;
- rtx insns;
+add_label_notes (rtx x, rtx insns)
{
enum rtx_code code = GET_CODE (x);
int i, j;
if (code == LABEL_REF && !LABEL_REF_NONLOCAL_P (x))
{
/* This code used to ignore labels that referred to dispatch tables to
- avoid flow generating (slighly) worse code.
+ avoid flow generating (slightly) worse code.
We no longer ignore such label references (see LABEL_REF handling in
mark_jump_label for additional information). */
other throughout. */
static void
-move_movables (loop, movables, threshold, insn_count)
- struct loop *loop;
- struct loop_movables *movables;
- int threshold;
- int insn_count;
+move_movables (struct loop *loop, struct loop_movables *movables,
+ int threshold, int insn_count)
{
struct loop_regs *regs = LOOP_REGS (loop);
int nregs = regs->num;
/* Map of pseudo-register replacements to handle combining
when we move several insns that load the same value
into different pseudo-registers. */
- rtx *reg_map = (rtx *) xcalloc (nregs, sizeof (rtx));
- char *already_moved = (char *) xcalloc (nregs, sizeof (char));
+ rtx *reg_map = xcalloc (nregs, sizeof (rtx));
+ char *already_moved = xcalloc (nregs, sizeof (char));
for (m = movables->head; m; m = m->next)
{
int count;
struct movable *m1;
rtx first = NULL_RTX;
+ rtx newreg = NULL_RTX;
+
+ if (m->insert_temp)
+ newreg = gen_reg_rtx (GET_MODE (m->set_dest));
/* Now move the insns that set the reg. */
insn stream. */
while (p && GET_CODE (p) == NOTE)
p = NEXT_INSN (temp) = NEXT_INSN (p);
+
+ if (m->insert_temp)
+ {
+ /* Replace the original insn with a move from
+ our newly created temp. */
+ start_sequence ();
+ emit_move_insn (m->set_dest, newreg);
+ seq = get_insns ();
+ end_sequence ();
+ emit_insn_before (seq, p);
+ }
}
start_sequence ();
- emit_move_insn (m->set_dest, m->set_src);
+ emit_move_insn (m->insert_temp ? newreg : m->set_dest,
+ m->set_src);
seq = get_insns ();
end_sequence ();
/* The SET_SRC might not be invariant, so we must
use the REG_EQUAL note. */
start_sequence ();
- emit_move_insn (m->set_dest, m->set_src);
+ emit_move_insn (m->insert_temp ? newreg : m->set_dest,
+ m->set_src);
seq = get_insns ();
end_sequence ();
set_unique_reg_note (i1, m->is_equiv ? REG_EQUIV
: REG_EQUAL, m->set_src);
}
+ else if (m->insert_temp)
+ {
+ rtx *reg_map2 = xcalloc (REGNO (newreg),
+ sizeof(rtx));
+ reg_map2 [m->regno] = newreg;
+
+ i1 = loop_insn_hoist (loop, copy_rtx (PATTERN (p)));
+ replace_regs (i1, reg_map2, REGNO (newreg), 1);
+ free (reg_map2);
+ }
else
i1 = loop_insn_hoist (loop, PATTERN (p));
insn stream. */
while (p && GET_CODE (p) == NOTE)
p = NEXT_INSN (temp) = NEXT_INSN (p);
+
+ if (m->insert_temp)
+ {
+ rtx seq;
+ /* Replace the original insn with a move from
+ our newly created temp. */
+ start_sequence ();
+ emit_move_insn (m->set_dest, newreg);
+ seq = get_insns ();
+ end_sequence ();
+ emit_insn_before (seq, p);
+ }
}
/* The more regs we move, the less we like moving them. */
threshold -= 3;
}
- /* Any other movable that loads the same register
- MUST be moved. */
- already_moved[regno] = 1;
-
- /* This reg has been moved out of one loop. */
- regs->array[regno].moved_once = 1;
+ m->done = 1;
- /* The reg set here is now invariant. */
- if (! m->partial)
+ if (!m->insert_temp)
{
- int i;
- for (i = 0; i < LOOP_REGNO_NREGS (regno, m->set_dest); i++)
- regs->array[regno+i].set_in_loop = 0;
- }
+ /* Any other movable that loads the same register
+ MUST be moved. */
+ already_moved[regno] = 1;
- m->done = 1;
+ /* This reg has been moved out of one loop. */
+ regs->array[regno].moved_once = 1;
- /* Change the length-of-life info for the register
- to say it lives at least the full length of this loop.
- This will help guide optimizations in outer loops. */
+ /* The reg set here is now invariant. */
+ if (! m->partial)
+ {
+ int i;
+ for (i = 0; i < LOOP_REGNO_NREGS (regno, m->set_dest); i++)
+ regs->array[regno+i].set_in_loop = 0;
+ }
- if (REGNO_FIRST_LUID (regno) > INSN_LUID (loop_start))
- /* This is the old insn before all the moved insns.
- We can't use the moved insn because it is out of range
- in uid_luid. Only the old insns have luids. */
- REGNO_FIRST_UID (regno) = INSN_UID (loop_start);
- if (REGNO_LAST_LUID (regno) < INSN_LUID (loop_end))
- REGNO_LAST_UID (regno) = INSN_UID (loop_end);
+ /* Change the length-of-life info for the register
+ to say it lives at least the full length of this loop.
+ This will help guide optimizations in outer loops. */
+
+ if (REGNO_FIRST_LUID (regno) > INSN_LUID (loop_start))
+ /* This is the old insn before all the moved insns.
+ We can't use the moved insn because it is out of range
+ in uid_luid. Only the old insns have luids. */
+ REGNO_FIRST_UID (regno) = INSN_UID (loop_start);
+ if (REGNO_LAST_LUID (regno) < INSN_LUID (loop_end))
+ REGNO_LAST_UID (regno) = INSN_UID (loop_end);
+ }
/* Combine with this moved insn any other matching movables. */
and prevent further processing of it. */
m1->done = 1;
- /* if library call, delete all insns. */
+ /* If library call, delete all insns. */
if ((temp = find_reg_note (m1->insn, REG_RETVAL,
NULL_RTX)))
delete_insn_chain (XEXP (temp, 0), m1->insn);
static void
-loop_movables_add (movables, m)
- struct loop_movables *movables;
- struct movable *m;
+loop_movables_add (struct loop_movables *movables, struct movable *m)
{
if (movables->head == 0)
movables->head = m;
static void
-loop_movables_free (movables)
- struct loop_movables *movables;
+loop_movables_free (struct loop_movables *movables)
{
struct movable *m;
struct movable *m_next;
REG is the address that MEM should have before the replacement. */
static void
-replace_call_address (x, reg, addr)
- rtx x, reg, addr;
+replace_call_address (rtx x, rtx reg, rtx addr)
{
enum rtx_code code;
int i;
in the rtx X. */
static int
-count_nonfixed_reads (loop, x)
- const struct loop *loop;
- rtx x;
+count_nonfixed_reads (const struct loop *loop, rtx x)
{
enum rtx_code code;
int i;
list `store_mems' in LOOP. */
static void
-prescan_loop (loop)
- struct loop *loop;
+prescan_loop (struct loop *loop)
{
int level = 1;
rtx insn;
loop_info->has_call = 1;
if (can_throw_internal (insn))
loop_info->has_multiple_exit_targets = 1;
+
+ /* Calls initializing constant objects have CLOBBER of MEM /u in the
+ attached FUNCTION_USAGE expression list, not accounted for by the
+ code above. We should note these to avoid missing dependencies in
+ later references. */
+ {
+ rtx fusage_entry;
+
+ for (fusage_entry = CALL_INSN_FUNCTION_USAGE (insn);
+ fusage_entry; fusage_entry = XEXP (fusage_entry, 1))
+ {
+ rtx fusage = XEXP (fusage_entry, 0);
+
+ if (GET_CODE (fusage) == CLOBBER
+ && GET_CODE (XEXP (fusage, 0)) == MEM
+ && RTX_UNCHANGING_P (XEXP (fusage, 0)))
+ {
+ note_stores (fusage, note_addr_stored, loop_info);
+ if (! loop_info->first_loop_store_insn
+ && loop_info->store_mems)
+ loop_info->first_loop_store_insn = insn;
+ }
+ }
+ }
break;
case JUMP_INSN:
loop_info->has_multiple_exit_targets = 1;
}
}
- /* FALLTHRU */
+ /* Fall through. */
case INSN:
if (volatile_refs_p (PATTERN (insn)))
/* Invalidate all loops containing LABEL. */
static void
-invalidate_loops_containing_label (label)
- rtx label;
+invalidate_loops_containing_label (rtx label)
{
struct loop *loop;
for (loop = uid_loop[INSN_UID (label)]; loop; loop = loop->outer)
to from outside the loop. */
static void
-find_and_verify_loops (f, loops)
- rtx f;
- struct loops *loops;
+find_and_verify_loops (rtx f, struct loops *loops)
{
rtx insn;
rtx label;
For speed, we assume that X is part of a pattern of a JUMP_INSN. */
static void
-mark_loop_jump (x, loop)
- rtx x;
- struct loop *loop;
+mark_loop_jump (rtx x, struct loop *loop)
{
struct loop *dest_loop;
struct loop *outer_loop;
been previously created by loop.c). */
static int
-labels_in_range_p (insn, end)
- rtx insn;
- int end;
+labels_in_range_p (rtx insn, int end)
{
while (insn && INSN_LUID (insn) <= end)
{
/* Record that a memory reference X is being set. */
static void
-note_addr_stored (x, y, data)
- rtx x;
- rtx y ATTRIBUTE_UNUSED;
- void *data ATTRIBUTE_UNUSED;
+note_addr_stored (rtx x, rtx y ATTRIBUTE_UNUSED,
+ void *data ATTRIBUTE_UNUSED)
{
struct loop_info *loop_info = data;
used more than once. DATA is a pointer to a loop_regs structure. */
static void
-note_set_pseudo_multiple_uses (x, y, data)
- rtx x;
- rtx y ATTRIBUTE_UNUSED;
- void *data;
+note_set_pseudo_multiple_uses (rtx x, rtx y ATTRIBUTE_UNUSED, void *data)
{
struct loop_regs *regs = (struct loop_regs *) data;
with anything stored in `loop_info->store_mems'. */
int
-loop_invariant_p (loop, x)
- const struct loop *loop;
- rtx x;
+loop_invariant_p (const struct loop *loop, rtx x)
{
struct loop_info *loop_info = LOOP_INFO (loop);
struct loop_regs *regs = LOOP_REGS (loop);
We don't know the loop bounds here though, so just fail for all
labels. */
- if (flag_unroll_loops)
+ if (flag_old_unroll_loops)
return 0;
else
return 1;
return 0;
/* Out-of-range regs can occur when we are called from unrolling.
- These have always been created by the unroller and are set in
- the loop, hence are never invariant. */
-
- if (REGNO (x) >= regs->num)
+ These registers created by the unroller are set in the loop,
+ hence are never invariant.
+ Other out-of-range regs can be generated by load_mems; those that
+ are written to in the loop are not invariant, while those that are
+ not written to are invariant. It would be easy for load_mems
+ to set n_times_set correctly for these registers, however, there
+ is no easy way to distinguish them from registers created by the
+ unroller. */
+
+ if (REGNO (x) >= (unsigned) regs->num)
return 0;
if (regs->array[REGNO (x)].set_in_loop < 0)
and that its source is invariant. */
static int
-consec_sets_invariant_p (loop, reg, n_sets, insn)
- const struct loop *loop;
- int n_sets;
- rtx reg, insn;
+consec_sets_invariant_p (const struct loop *loop, rtx reg, int n_sets,
+ rtx insn)
{
struct loop_regs *regs = LOOP_REGS (loop);
rtx p = insn;
/* If loop_invariant_p ever returned 2, we return 2. */
return 1 + (value & 2);
}
-
-#if 0
-/* I don't think this condition is sufficient to allow INSN
- to be moved, so we no longer test it. */
-
-/* Return 1 if all insns in the basic block of INSN and following INSN
- that set REG are invariant according to TABLE. */
-
-static int
-all_sets_invariant_p (reg, insn, table)
- rtx reg, insn;
- short *table;
-{
- rtx p = insn;
- int regno = REGNO (reg);
-
- while (1)
- {
- enum rtx_code code;
- p = NEXT_INSN (p);
- code = GET_CODE (p);
- if (code == CODE_LABEL || code == JUMP_INSN)
- return 1;
- if (code == INSN && GET_CODE (PATTERN (p)) == SET
- && GET_CODE (SET_DEST (PATTERN (p))) == REG
- && REGNO (SET_DEST (PATTERN (p))) == regno)
- {
- if (! loop_invariant_p (loop, SET_SRC (PATTERN (p)), table))
- return 0;
- }
- }
-}
-#endif /* 0 */
\f
/* Look at all uses (not sets) of registers in X. For each, if it is
the single use, set USAGE[REGNO] to INSN; if there was a previous use in
a different insn, set USAGE[REGNO] to const0_rtx. */
static void
-find_single_use_in_loop (regs, insn, x)
- struct loop_regs *regs;
- rtx insn;
- rtx x;
+find_single_use_in_loop (struct loop_regs *regs, rtx insn, rtx x)
{
enum rtx_code code = GET_CODE (x);
const char *fmt = GET_RTX_FORMAT (code);
in X. */
static void
-count_one_set (regs, insn, x, last_set)
- struct loop_regs *regs;
- rtx insn, x;
- rtx *last_set;
+count_one_set (struct loop_regs *regs, rtx insn, rtx x, rtx *last_set)
{
if (GET_CODE (x) == CLOBBER && GET_CODE (XEXP (x, 0)) == REG)
/* Don't move a reg that has an explicit clobber.
it must be set in two basic blocks, so it cannot
be moved out of the loop. */
if (regs->array[regno].set_in_loop > 0
- && last_set == 0)
+ && last_set[regno] == 0)
regs->array[regno+i].may_not_optimize = 1;
/* If this is not first setting in current basic block,
see if reg was used in between previous one and this.
from an inner loop past two loops. */
static int
-loop_reg_used_before_p (loop, set, insn)
- const struct loop *loop;
- rtx set, insn;
+loop_reg_used_before_p (const struct loop *loop, rtx set, rtx insn)
{
rtx reg = SET_DEST (set);
rtx p;
int mem_write;
};
-static void check_store PARAMS ((rtx, rtx, void *));
-static void emit_prefetch_instructions PARAMS ((struct loop *));
-static int rtx_equal_for_prefetch_p PARAMS ((rtx, rtx));
+static void check_store (rtx, rtx, void *);
+static void emit_prefetch_instructions (struct loop *);
+static int rtx_equal_for_prefetch_p (rtx, rtx);
/* Set mem_write when mem_address is found. Used as callback to
note_stores. */
static void
-check_store (x, pat, data)
- rtx x, pat ATTRIBUTE_UNUSED;
- void *data;
+check_store (rtx x, rtx pat ATTRIBUTE_UNUSED, void *data)
{
struct check_store_data *d = (struct check_store_data *) data;
\f
/* Like rtx_equal_p, but attempts to swap commutative operands. This is
important to get some addresses combined. Later more sophisticated
- transformations can be added when necesary.
+ transformations can be added when necessary.
??? Same trick with swapping operand is done at several other places.
It can be nice to develop some common way to handle this. */
static int
-rtx_equal_for_prefetch_p (x, y)
- rtx x, y;
+rtx_equal_for_prefetch_p (rtx x, rtx y)
{
int i;
int j;
if (code != GET_CODE (y))
return 0;
- code = GET_CODE (x);
-
- if (GET_RTX_CLASS (code) == 'c')
+ if (COMMUTATIVE_ARITH_P (x))
{
return ((rtx_equal_for_prefetch_p (XEXP (x, 0), XEXP (y, 0))
&& rtx_equal_for_prefetch_p (XEXP (x, 1), XEXP (y, 1)))
|| (rtx_equal_for_prefetch_p (XEXP (x, 0), XEXP (y, 1))
&& rtx_equal_for_prefetch_p (XEXP (x, 1), XEXP (y, 0))));
}
+
/* Compare the elements. If any pair of corresponding elements fails to
match, return 0 for the whole thing. */
and return it. */
static HOST_WIDE_INT
-remove_constant_addition (x)
- rtx *x;
+remove_constant_addition (rtx *x)
{
HOST_WIDE_INT addval = 0;
rtx exp = *x;
controlled by defined symbols that can be overridden for each target. */
static void
-emit_prefetch_instructions (loop)
- struct loop *loop;
+emit_prefetch_instructions (struct loop *loop)
{
int num_prefetches = 0;
int num_real_prefetches = 0;
" density: %d%%; bytes_accessed: %u; total_bytes: %u\n",
(int) (info[i].bytes_accessed * 100 / info[i].stride),
info[i].bytes_accessed, info[i].total_bytes);
- fprintf (loop_dump_stream, " index: ");
- fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, info[i].index);
- fprintf (loop_dump_stream, "; stride: ");
- fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, info[i].stride);
- fprintf (loop_dump_stream, "; address: ");
+ fprintf (loop_dump_stream, " index: " HOST_WIDE_INT_PRINT_DEC
+ "; stride: " HOST_WIDE_INT_PRINT_DEC "; address: ",
+ info[i].index, info[i].stride);
print_rtl (loop_dump_stream, info[i].base_address);
fprintf (loop_dump_stream, "\n");
}
{
rtx reg = gen_reg_rtx (Pmode);
loop_iv_add_mult_emit_before (loop, loc, const1_rtx,
- GEN_INT (bytes_ahead), reg,
- 0, before_insn);
+ GEN_INT (bytes_ahead), reg,
+ 0, before_insn);
loc = reg;
}
non-constant INIT_VAL to have the same mode as REG, which
in this case we know to be Pmode. */
if (GET_MODE (init_val) != Pmode && !CONSTANT_P (init_val))
- init_val = convert_to_mode (Pmode, init_val, 0);
+ {
+ rtx seq;
+
+ start_sequence ();
+ init_val = convert_to_mode (Pmode, init_val, 0);
+ seq = get_insns ();
+ end_sequence ();
+ loop_insn_emit_before (loop, 0, loop_start, seq);
+ }
loop_iv_add_mult_emit_before (loop, init_val,
info[i].giv->mult_val,
add_val, reg, 0, loop_start);
return;
}
\f
-/* A "basic induction variable" or biv is a pseudo reg that is set
- (within this loop) only by incrementing or decrementing it. */
-/* A "general induction variable" or giv is a pseudo reg whose
- value is a linear function of a biv. */
-
-/* Bivs are recognized by `basic_induction_var';
- Givs by `general_induction_var'. */
-
/* Communication with routines called via `note_stores'. */
static rtx note_insn;
loop iteration.
*/
void
-for_each_insn_in_loop (loop, fncall)
- struct loop *loop;
- loop_insn_callback fncall;
+for_each_insn_in_loop (struct loop *loop, loop_insn_callback fncall)
{
int not_every_iteration = 0;
int maybe_multiple = 0;
}
\f
static void
-loop_bivs_find (loop)
- struct loop *loop;
+loop_bivs_find (struct loop *loop)
{
struct loop_regs *regs = LOOP_REGS (loop);
struct loop_ivs *ivs = LOOP_IVS (loop);
/* Determine how BIVS are initialized by looking through pre-header
extended basic block. */
static void
-loop_bivs_init_find (loop)
- struct loop *loop;
+loop_bivs_init_find (struct loop *loop)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
/* Temporary list pointers for traversing ivs->list. */
initial value from any initializing insns set up above. (This is done
in two passes to avoid missing SETs in a PARALLEL.) */
static void
-loop_bivs_check (loop)
- struct loop *loop;
+loop_bivs_check (struct loop *loop)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
/* Temporary list pointers for traversing ivs->list. */
/* Search the loop for general induction variables. */
static void
-loop_givs_find (loop)
- struct loop* loop;
+loop_givs_find (struct loop* loop)
{
for_each_insn_in_loop (loop, check_insn_for_givs);
}
can be calculated. */
static void
-loop_givs_check (loop)
- struct loop *loop;
+loop_givs_check (struct loop *loop)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
struct iv_class *bl;
be. */
static int
-loop_biv_eliminable_p (loop, bl, threshold, insn_count)
- struct loop *loop;
- struct iv_class *bl;
- int threshold;
- int insn_count;
+loop_biv_eliminable_p (struct loop *loop, struct iv_class *bl,
+ int threshold, int insn_count)
{
/* For architectures with a decrement_and_branch_until_zero insn,
don't do this if we put a REG_NONNEG note on the endtest for this
/* Reduce each giv of BL that we have decided to reduce. */
static void
-loop_givs_reduce (loop, bl)
- struct loop *loop;
- struct iv_class *bl;
+loop_givs_reduce (struct loop *loop, struct iv_class *bl)
{
struct induction *v;
{
rtx insert_before;
+ /* Skip if location is the same as a previous one. */
+ if (tv->same)
+ continue;
if (! auto_inc_opt)
insert_before = NEXT_INSN (tv->insn);
else if (auto_inc_opt == 1)
eliminate a biv. */
static void
-loop_givs_dead_check (loop, bl)
- struct loop *loop ATTRIBUTE_UNUSED;
- struct iv_class *bl;
+loop_givs_dead_check (struct loop *loop ATTRIBUTE_UNUSED, struct iv_class *bl)
{
struct induction *v;
static void
-loop_givs_rescan (loop, bl, reg_map)
- struct loop *loop;
- struct iv_class *bl;
- rtx *reg_map;
+loop_givs_rescan (struct loop *loop, struct iv_class *bl, rtx *reg_map)
{
struct induction *v;
gen_move_insn (v->dest_reg,
v->new_reg));
- /* The original insn may have a REG_EQUAL note. This note is
- now incorrect and may result in invalid substitutions later.
- The original insn is dead, but may be part of a libcall
- sequence, which doesn't seem worth the bother of handling. */
- note = find_reg_note (original_insn, REG_EQUAL, NULL_RTX);
- if (note)
- remove_note (original_insn, note);
+ /* The original insn may have a REG_EQUAL note. This note is
+ now incorrect and may result in invalid substitutions later.
+ The original insn is dead, but may be part of a libcall
+ sequence, which doesn't seem worth the bother of handling. */
+ note = find_reg_note (original_insn, REG_EQUAL, NULL_RTX);
+ if (note)
+ remove_note (original_insn, note);
}
/* When a loop is reversed, givs which depend on the reversed
static int
-loop_giv_reduce_benefit (loop, bl, v, test_reg)
- struct loop *loop ATTRIBUTE_UNUSED;
- struct iv_class *bl;
- struct induction *v;
- rtx test_reg;
+loop_giv_reduce_benefit (struct loop *loop ATTRIBUTE_UNUSED,
+ struct iv_class *bl, struct induction *v,
+ rtx test_reg)
{
int add_cost;
int benefit;
/* Free IV structures for LOOP. */
static void
-loop_ivs_free (loop)
- struct loop *loop;
+loop_ivs_free (struct loop *loop)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
struct iv_class *iv = ivs->list;
must check regnos to make sure they are in bounds. */
static void
-strength_reduce (loop, flags)
- struct loop *loop;
- int flags;
+strength_reduce (struct loop *loop, int flags)
{
struct loop_info *loop_info = LOOP_INFO (loop);
struct loop_regs *regs = LOOP_REGS (loop);
addr_placeholder = gen_reg_rtx (Pmode);
ivs->n_regs = max_reg_before_loop;
- ivs->regs = (struct iv *) xcalloc (ivs->n_regs, sizeof (struct iv));
+ ivs->regs = xcalloc (ivs->n_regs, sizeof (struct iv));
/* Find all BIVs in loop. */
loop_bivs_find (loop);
Some givs might have been made from biv increments, so look at
ivs->reg_iv_type for a suitable size. */
reg_map_size = ivs->n_regs;
- reg_map = (rtx *) xcalloc (reg_map_size, sizeof (rtx));
+ reg_map = xcalloc (reg_map_size, sizeof (rtx));
/* Examine each iv class for feasibility of strength reduction/induction
variable elimination. */
/* Check each extension dependent giv in this class to see if its
root biv is safe from wrapping in the interior mode. */
- check_ext_dependent_givs (bl, loop_info);
+ check_ext_dependent_givs (loop, bl);
/* Combine all giv's for this iv_class. */
combine_givs (regs, bl);
&& unrolled_insn_copies <= insn_count))
unroll_loop (loop, insn_count, 1);
-#ifdef HAVE_doloop_end
- if (HAVE_doloop_end && (flags & LOOP_BCT) && flag_branch_on_count_reg)
- doloop_optimize (loop);
-#endif /* HAVE_doloop_end */
-
- /* In case number of iterations is known, drop branch prediction note
- in the branch. Do that only in second loop pass, as loop unrolling
- may change the number of iterations performed. */
- if (flags & LOOP_BCT)
- {
- unsigned HOST_WIDE_INT n
- = loop_info->n_iterations / loop_info->unroll_number;
- if (n > 1)
- predict_insn (prev_nonnote_insn (loop->end), PRED_LOOP_ITERATIONS,
- REG_BR_PROB_BASE - REG_BR_PROB_BASE / n);
- }
-
if (loop_dump_stream)
fprintf (loop_dump_stream, "\n");
\f
/*Record all basic induction variables calculated in the insn. */
static rtx
-check_insn_for_bivs (loop, p, not_every_iteration, maybe_multiple)
- struct loop *loop;
- rtx p;
- int not_every_iteration;
- int maybe_multiple;
+check_insn_for_bivs (struct loop *loop, rtx p, int not_every_iteration,
+ int maybe_multiple)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
rtx set;
/* It is a possible basic induction variable.
Create and initialize an induction structure for it. */
- struct induction *v
- = (struct induction *) xmalloc (sizeof (struct induction));
+ struct induction *v = xmalloc (sizeof (struct induction));
record_biv (loop, v, p, dest_reg, inc_val, mult_val, location,
not_every_iteration, maybe_multiple);
A register is a giv if: it is only set once, it is a function of a
biv and a constant (or invariant), and it is not a biv. */
static rtx
-check_insn_for_givs (loop, p, not_every_iteration, maybe_multiple)
- struct loop *loop;
- rtx p;
- int not_every_iteration;
- int maybe_multiple;
+check_insn_for_givs (struct loop *loop, rtx p, int not_every_iteration,
+ int maybe_multiple)
{
struct loop_regs *regs = LOOP_REGS (loop);
&add_val, &mult_val, &ext_val,
&last_consec_insn))))
{
- struct induction *v
- = (struct induction *) xmalloc (sizeof (struct induction));
+ struct induction *v = xmalloc (sizeof (struct induction));
/* If this is a library call, increase benefit. */
if (find_reg_note (p, REG_RETVAL, NULL_RTX))
}
}
-#ifndef DONT_REDUCE_ADDR
/* Look for givs which are memory addresses. */
- /* This resulted in worse code on a VAX 8600. I wonder if it
- still does. */
if (GET_CODE (p) == INSN)
find_mem_givs (loop, PATTERN (p), p, not_every_iteration,
maybe_multiple);
-#endif
/* Update the status of whether giv can derive other givs. This can
change when we pass a label or an insn that updates a biv. */
INSN is the insn containing X. */
static int
-valid_initial_value_p (x, insn, call_seen, loop_start)
- rtx x;
- rtx insn;
- int call_seen;
- rtx loop_start;
+valid_initial_value_p (rtx x, rtx insn, int call_seen, rtx loop_start)
{
if (CONSTANT_P (x))
return 1;
as a possible giv. INSN is the insn whose pattern X comes from.
NOT_EVERY_ITERATION is 1 if the insn might not be executed during
every loop iteration. MAYBE_MULTIPLE is 1 if the insn might be executed
- more thanonce in each loop iteration. */
+ more than once in each loop iteration. */
static void
-find_mem_givs (loop, x, insn, not_every_iteration, maybe_multiple)
- const struct loop *loop;
- rtx x;
- rtx insn;
- int not_every_iteration, maybe_multiple;
+find_mem_givs (const struct loop *loop, rtx x, rtx insn,
+ int not_every_iteration, int maybe_multiple)
{
int i, j;
enum rtx_code code;
GET_MODE (x)))
{
/* Found one; record it. */
- struct induction *v
- = (struct induction *) xmalloc (sizeof (struct induction));
+ struct induction *v = xmalloc (sizeof (struct induction));
record_giv (loop, v, insn, src_reg, addr_placeholder, mult_val,
add_val, ext_val, benefit, DEST_ADDR,
executed exactly once per iteration. */
static void
-record_biv (loop, v, insn, dest_reg, inc_val, mult_val, location,
- not_every_iteration, maybe_multiple)
- struct loop *loop;
- struct induction *v;
- rtx insn;
- rtx dest_reg;
- rtx inc_val;
- rtx mult_val;
- rtx *location;
- int not_every_iteration;
- int maybe_multiple;
+record_biv (struct loop *loop, struct induction *v, rtx insn, rtx dest_reg,
+ rtx inc_val, rtx mult_val, rtx *location,
+ int not_every_iteration, int maybe_multiple)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
struct iv_class *bl;
v->always_computable = ! not_every_iteration;
v->always_executed = ! not_every_iteration;
v->maybe_multiple = maybe_multiple;
+ v->same = 0;
/* Add this to the reg's iv_class, creating a class
if this is the first incrementation of the reg. */
{
/* Create and initialize new iv_class. */
- bl = (struct iv_class *) xmalloc (sizeof (struct iv_class));
+ bl = xmalloc (sizeof (struct iv_class));
bl->regno = REGNO (dest_reg);
bl->biv = 0;
/* Set initial value to the reg itself. */
bl->initial_value = dest_reg;
bl->final_value = 0;
- /* We haven't seen the initializing insn yet */
+ /* We haven't seen the initializing insn yet. */
bl->init_insn = 0;
bl->init_set = 0;
bl->initial_test = 0;
/* Put it in the array of biv register classes. */
REG_IV_CLASS (ivs, REGNO (dest_reg)) = bl;
}
+ else
+ {
+ /* Check if location is the same as a previous one. */
+ struct induction *induction;
+ for (induction = bl->biv; induction; induction = induction->next_iv)
+ if (location == induction->location)
+ {
+ v->same = induction;
+ break;
+ }
+ }
/* Update IV_CLASS entry for this biv. */
v->next_iv = bl->biv;
LOCATION points to the place where this giv's value appears in INSN. */
static void
-record_giv (loop, v, insn, src_reg, dest_reg, mult_val, add_val, ext_val,
- benefit, type, not_every_iteration, maybe_multiple, location)
- const struct loop *loop;
- struct induction *v;
- rtx insn;
- rtx src_reg;
- rtx dest_reg;
- rtx mult_val, add_val, ext_val;
- int benefit;
- enum g_types type;
- int not_every_iteration, maybe_multiple;
- rtx *location;
+record_giv (const struct loop *loop, struct induction *v, rtx insn,
+ rtx src_reg, rtx dest_reg, rtx mult_val, rtx add_val,
+ rtx ext_val, int benefit, enum g_types type,
+ int not_every_iteration, int maybe_multiple, rtx *location)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
struct induction *b;
rtx set = single_set (insn);
rtx temp;
- /* Attempt to prove constantness of the values. Don't let simplity_rtx
+ /* Attempt to prove constantness of the values. Don't let simplify_rtx
undo the MULT canonicalization that we performed earlier. */
temp = simplify_rtx (add_val);
if (temp
have been identified. */
static void
-check_final_value (loop, v)
- const struct loop *loop;
- struct induction *v;
+check_final_value (const struct loop *loop, struct induction *v)
{
rtx final_value = 0;
The cases we look at are when a label or an update to a biv is passed. */
static void
-update_giv_derive (loop, p)
- const struct loop *loop;
- rtx p;
+update_giv_derive (const struct loop *loop, rtx p)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
struct iv_class *bl;
if (GET_CODE (p) == CODE_LABEL || GET_CODE (p) == JUMP_INSN
|| biv->insn == p)
{
+ /* Skip if location is the same as a previous one. */
+ if (biv->same)
+ continue;
+
for (giv = bl->giv; giv; giv = giv->next_iv)
{
/* If cant_derive is already true, there is no point in
*MULT_VAL to CONST0_RTX, and store the invariant into *INC_VAL.
We also want to detect a BIV when it corresponds to a variable
- whose mode was promoted via PROMOTED_MODE. In that case, an increment
+ whose mode was promoted. In that case, an increment
of the variable may be a PLUS that adds a SUBREG of that variable to
an invariant and then sign- or zero-extends the result of the PLUS
into the variable.
If we cannot find a biv, we return 0. */
static int
-basic_induction_var (loop, x, mode, dest_reg, p, inc_val, mult_val, location)
- const struct loop *loop;
- rtx x;
- enum machine_mode mode;
- rtx dest_reg;
- rtx p;
- rtx *inc_val;
- rtx *mult_val;
- rtx **location;
+basic_induction_var (const struct loop *loop, rtx x, enum machine_mode mode,
+ rtx dest_reg, rtx p, rtx *inc_val, rtx *mult_val,
+ rtx **location)
{
enum rtx_code code;
rtx *argp, arg;
- rtx insn, set = 0;
+ rtx insn, set = 0, last, inc;
code = GET_CODE (x);
*location = NULL;
if (loop_invariant_p (loop, arg) != 1)
return 0;
- *inc_val = convert_modes (GET_MODE (dest_reg), GET_MODE (x), arg, 0);
+ /* convert_modes can emit new instructions, e.g. when arg is a loop
+ invariant MEM and dest_reg has a different mode.
+ These instructions would be emitted after the end of the function
+ and then *inc_val would be an uninitialized pseudo.
+ Detect this and bail in this case.
+ Other alternatives to solve this can be introducing a convert_modes
+ variant which is allowed to fail but not allowed to emit new
+ instructions, emit these instructions before loop start and let
+ it be garbage collected if *inc_val is never used or saving the
+ *inc_val initialization sequence generated here and when *inc_val
+ is going to be actually used, emit it at some suitable place. */
+ last = get_last_insn ();
+ inc = convert_modes (GET_MODE (dest_reg), GET_MODE (x), arg, 0);
+ if (get_last_insn () != last)
+ {
+ delete_insns_since (last);
+ return 0;
+ }
+
+ *inc_val = inc;
*mult_val = const1_rtx;
*location = argp;
return 1;
&& GET_MODE_CLASS (mode) != MODE_CC)
{
/* Possible bug here? Perhaps we don't know the mode of X. */
- *inc_val = convert_modes (GET_MODE (dest_reg), mode, x, 0);
+ last = get_last_insn ();
+ inc = convert_modes (GET_MODE (dest_reg), mode, x, 0);
+ if (get_last_insn () != last)
+ {
+ delete_insns_since (last);
+ return 0;
+ }
+
+ *inc_val = inc;
*mult_val = const0_rtx;
return 1;
}
return 0;
case SIGN_EXTEND:
+ /* Ignore this BIV if signed arithmetic overflow is defined. */
+ if (flag_wrapv)
+ return 0;
return basic_induction_var (loop, XEXP (x, 0), GET_MODE (XEXP (x, 0)),
dest_reg, p, inc_val, mult_val, location);
such that the value of X is biv * mult + add; */
static int
-general_induction_var (loop, x, src_reg, add_val, mult_val, ext_val,
- is_addr, pbenefit, addr_mode)
- const struct loop *loop;
- rtx x;
- rtx *src_reg;
- rtx *add_val;
- rtx *mult_val;
- rtx *ext_val;
- int is_addr;
- int *pbenefit;
- enum machine_mode addr_mode;
+general_induction_var (const struct loop *loop, rtx x, rtx *src_reg,
+ rtx *add_val, rtx *mult_val, rtx *ext_val,
+ int is_addr, int *pbenefit,
+ enum machine_mode addr_mode)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
rtx orig_x = x;
*BENEFIT will be incremented by the benefit of any sub-giv encountered. */
-static rtx sge_plus PARAMS ((enum machine_mode, rtx, rtx));
-static rtx sge_plus_constant PARAMS ((rtx, rtx));
+static rtx sge_plus (enum machine_mode, rtx, rtx);
+static rtx sge_plus_constant (rtx, rtx);
static rtx
-simplify_giv_expr (loop, x, ext_val, benefit)
- const struct loop *loop;
- rtx x;
- rtx *ext_val;
- int *benefit;
+simplify_giv_expr (const struct loop *loop, rtx x, rtx *ext_val, int *benefit)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
struct loop_regs *regs = LOOP_REGS (loop);
arg1)),
ext_val, benefit);
}
- /* Porpagate the MULT expressions to the intermost nodes. */
+ /* Propagate the MULT expressions to the innermost nodes. */
else if (GET_CODE (arg0) == PLUS)
{
/* (invar_0 + invar_1) * invar_2. Distribute. */
CONST_INT in the summation. It is only used by simplify_giv_expr. */
static rtx
-sge_plus_constant (x, c)
- rtx x, c;
+sge_plus_constant (rtx x, rtx c)
{
if (GET_CODE (x) == CONST_INT)
return GEN_INT (INTVAL (x) + INTVAL (c));
}
static rtx
-sge_plus (mode, x, y)
- enum machine_mode mode;
- rtx x, y;
+sge_plus (enum machine_mode mode, rtx x, rtx y)
{
while (GET_CODE (y) == PLUS)
{
*MULT_VAL and *ADD_VAL. */
static int
-consec_sets_giv (loop, first_benefit, p, src_reg, dest_reg,
- add_val, mult_val, ext_val, last_consec_insn)
- const struct loop *loop;
- int first_benefit;
- rtx p;
- rtx src_reg;
- rtx dest_reg;
- rtx *add_val;
- rtx *mult_val;
- rtx *ext_val;
- rtx *last_consec_insn;
+consec_sets_giv (const struct loop *loop, int first_benefit, rtx p,
+ rtx src_reg, rtx dest_reg, rtx *add_val, rtx *mult_val,
+ rtx *ext_val, rtx *last_consec_insn)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
struct loop_regs *regs = LOOP_REGS (loop);
if (REG_IV_TYPE (ivs, REGNO (dest_reg)) != UNKNOWN_INDUCT)
return 0;
- v = (struct induction *) alloca (sizeof (struct induction));
+ v = alloca (sizeof (struct induction));
v->src_reg = src_reg;
v->mult_val = *mult_val;
v->add_val = *add_val;
subtracting variables. */
static rtx
-express_from_1 (a, b, mult)
- rtx a, b, mult;
+express_from_1 (rtx a, rtx b, rtx mult)
{
/* If MULT is zero, then A*MULT is zero, and our expression is B. */
}
rtx
-express_from (g1, g2)
- struct induction *g1, *g2;
+express_from (struct induction *g1, struct induction *g2)
{
rtx mult, add;
&& GET_CODE (g2->mult_val) == CONST_INT)
{
if (g1->mult_val == const0_rtx
+ || (g1->mult_val == constm1_rtx
+ && INTVAL (g2->mult_val)
+ == (HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT - 1))
|| INTVAL (g2->mult_val) % INTVAL (g1->mult_val) != 0)
return NULL_RTX;
mult = GEN_INT (INTVAL (g2->mult_val) / INTVAL (g1->mult_val));
used to represent G1. */
static rtx
-combine_givs_p (g1, g2)
- struct induction *g1, *g2;
+combine_givs_p (struct induction *g1, struct induction *g2)
{
rtx comb, ret;
the expression of G2 in terms of G1 can be used. */
if (ret != NULL_RTX
&& g2->giv_type == DEST_ADDR
- && memory_address_p (GET_MODE (g2->mem), ret)
- /* ??? Looses, especially with -fforce-addr, where *g2->location
- will always be a register, and so anything more complicated
- gets discarded. */
-#if 0
-#ifdef ADDRESS_COST
- && ADDRESS_COST (tem) <= ADDRESS_COST (*g2->location)
-#else
- && rtx_cost (tem, MEM) <= rtx_cost (*g2->location, MEM)
-#endif
-#endif
- )
- {
- return ret;
- }
+ && memory_address_p (GET_MODE (g2->mem), ret))
+ return ret;
return NULL_RTX;
}
make the giv illegal. */
static void
-check_ext_dependent_givs (bl, loop_info)
- struct iv_class *bl;
- struct loop_info *loop_info;
+check_ext_dependent_givs (const struct loop *loop, struct iv_class *bl)
{
+ struct loop_info *loop_info = LOOP_INFO (loop);
int ze_ok = 0, se_ok = 0, info_ok = 0;
enum machine_mode biv_mode = GET_MODE (bl->biv->src_reg);
HOST_WIDE_INT start_val;
/* Make sure the iteration data is available. We must have
constants in order to be certain of no overflow. */
- /* ??? An unknown iteration count with an increment of +-1
- combined with friendly exit tests of against an invariant
- value is also ameanable to optimization. Not implemented. */
if (loop_info->n_iterations > 0
&& bl->initial_value
&& GET_CODE (bl->initial_value) == CONST_INT
neg_incr = 1, abs_incr = -abs_incr;
total_incr = abs_incr * loop_info->n_iterations;
- /* Check for host arithmatic overflow. */
+ /* Check for host arithmetic overflow. */
if (total_incr / loop_info->n_iterations == abs_incr)
{
unsigned HOST_WIDE_INT u_max;
/* Check zero extension of biv ok. */
if (start_val >= 0
- /* Check for host arithmatic overflow. */
+ /* Check for host arithmetic overflow. */
&& (neg_incr
? u_end_val < u_start_val
: u_end_val > u_start_val)
keep this fact in mind -- myself included on occasion.
So leave alone with the signed overflow optimizations. */
if (start_val >= -s_max - 1
- /* Check for host arithmatic overflow. */
+ /* Check for host arithmetic overflow. */
&& (neg_incr
? s_end_val < start_val
: s_end_val > start_val)
}
}
+ /* If we know the BIV is compared at run-time against an
+ invariant value, and the increment is +/- 1, we may also
+ be able to prove that the BIV cannot overflow. */
+ else if (bl->biv->src_reg == loop_info->iteration_var
+ && loop_info->comparison_value
+ && loop_invariant_p (loop, loop_info->comparison_value)
+ && (incr = biv_total_increment (bl))
+ && GET_CODE (incr) == CONST_INT)
+ {
+ /* If the increment is +1, and the exit test is a <,
+ the BIV cannot overflow. (For <=, we have the
+ problematic case that the comparison value might
+ be the maximum value of the range.) */
+ if (INTVAL (incr) == 1)
+ {
+ if (loop_info->comparison_code == LT)
+ se_ok = ze_ok = 1;
+ else if (loop_info->comparison_code == LTU)
+ ze_ok = 1;
+ }
+
+ /* Likewise for increment -1 and exit test >. */
+ if (INTVAL (incr) == -1)
+ {
+ if (loop_info->comparison_code == GT)
+ se_ok = ze_ok = 1;
+ else if (loop_info->comparison_code == GTU)
+ ze_ok = 1;
+ }
+ }
+
/* Invalidate givs that fail the tests. */
for (v = bl->giv; v; v = v->next_iv)
if (v->ext_dependent)
signed or unsigned, so to safely truncate we must satisfy
both. The initial check here verifies the BIV itself;
once that is successful we may check its range wrt the
- derived GIV. */
- if (se_ok && ze_ok)
+ derived GIV. This works only if we were able to determine
+ constant start and end values above. */
+ if (se_ok && ze_ok && info_ok)
{
enum machine_mode outer_mode = GET_MODE (v->ext_dependent);
unsigned HOST_WIDE_INT max = GET_MODE_MASK (outer_mode) >> 1;
/* Generate a version of VALUE in a mode appropriate for initializing V. */
rtx
-extend_value_for_giv (v, value)
- struct induction *v;
- rtx value;
+extend_value_for_giv (struct induction *v, rtx value)
{
rtx ext_dep = v->ext_dependent;
};
static int
-cmp_combine_givs_stats (xp, yp)
- const PTR xp;
- const PTR yp;
+cmp_combine_givs_stats (const void *xp, const void *yp)
{
const struct combine_givs_stats * const x =
(const struct combine_givs_stats *) xp;
giv. Also, update BENEFIT and related fields for cost/benefit analysis. */
static void
-combine_givs (regs, bl)
- struct loop_regs *regs;
- struct iv_class *bl;
+combine_givs (struct loop_regs *regs, struct iv_class *bl)
{
/* Additional benefit to add for being combined multiple times. */
const int extra_benefit = 3;
if (!g1->ignore)
giv_count++;
- giv_array
- = (struct induction **) alloca (giv_count * sizeof (struct induction *));
+ giv_array = alloca (giv_count * sizeof (struct induction *));
i = 0;
for (g1 = bl->giv; g1; g1 = g1->next_iv)
if (!g1->ignore)
giv_array[i++] = g1;
- stats = (struct combine_givs_stats *) xcalloc (giv_count, sizeof (*stats));
- can_combine = (rtx *) xcalloc (giv_count, giv_count * sizeof (rtx));
+ stats = xcalloc (giv_count, sizeof (*stats));
+ can_combine = xcalloc (giv_count, giv_count * sizeof (rtx));
for (i = 0; i < giv_count; i++)
{
free (can_combine);
}
\f
-/* Generate sequence for REG = B * M + A. */
+/* Generate sequence for REG = B * M + A. B is the initial value of
+ the basic induction variable, M a multiplicative constant, A an
+ additive constant and REG the destination register. */
static rtx
-gen_add_mult (b, m, a, reg)
- rtx b; /* initial value of basic induction variable */
- rtx m; /* multiplicative constant */
- rtx a; /* additive constant */
- rtx reg; /* destination register */
+gen_add_mult (rtx b, rtx m, rtx a, rtx reg)
{
rtx seq;
rtx result;
/* Update registers created in insn sequence SEQ. */
static void
-loop_regs_update (loop, seq)
- const struct loop *loop ATTRIBUTE_UNUSED;
- rtx seq;
+loop_regs_update (const struct loop *loop ATTRIBUTE_UNUSED, rtx seq)
{
rtx insn;
/* Update register info for alias analysis. */
- if (seq == NULL_RTX)
- return;
-
- if (INSN_P (seq))
+ insn = seq;
+ while (insn != NULL_RTX)
{
- insn = seq;
- while (insn != NULL_RTX)
- {
- rtx set = single_set (insn);
+ rtx set = single_set (insn);
- if (set && GET_CODE (SET_DEST (set)) == REG)
- record_base_value (REGNO (SET_DEST (set)), SET_SRC (set), 0);
+ if (set && GET_CODE (SET_DEST (set)) == REG)
+ record_base_value (REGNO (SET_DEST (set)), SET_SRC (set), 0);
- insn = NEXT_INSN (insn);
- }
+ insn = NEXT_INSN (insn);
}
- else if (GET_CODE (seq) == SET
- && GET_CODE (SET_DEST (seq)) == REG)
- record_base_value (REGNO (SET_DEST (seq)), SET_SRC (seq), 0);
}
-/* EMIT code before BEFORE_BB/BEFORE_INSN to set REG = B * M + A. */
+/* EMIT code before BEFORE_BB/BEFORE_INSN to set REG = B * M + A. B
+ is the initial value of the basic induction variable, M a
+ multiplicative constant, A an additive constant and REG the
+ destination register. */
void
-loop_iv_add_mult_emit_before (loop, b, m, a, reg, before_bb, before_insn)
- const struct loop *loop;
- rtx b; /* initial value of basic induction variable */
- rtx m; /* multiplicative constant */
- rtx a; /* additive constant */
- rtx reg; /* destination register */
- basic_block before_bb;
- rtx before_insn;
+loop_iv_add_mult_emit_before (const struct loop *loop, rtx b, rtx m, rtx a,
+ rtx reg, basic_block before_bb, rtx before_insn)
{
rtx seq;
update_reg_last_use (b, before_insn);
update_reg_last_use (m, before_insn);
- loop_insn_emit_before (loop, before_bb, before_insn, seq);
-
/* It is possible that the expansion created lots of new registers.
- Iterate over the sequence we just created and record them all. */
+ Iterate over the sequence we just created and record them all. We
+ must do this before inserting the sequence. */
loop_regs_update (loop, seq);
+
+ loop_insn_emit_before (loop, before_bb, before_insn, seq);
}
-/* Emit insns in loop pre-header to set REG = B * M + A. */
+/* Emit insns in loop pre-header to set REG = B * M + A. B is the
+ initial value of the basic induction variable, M a multiplicative
+ constant, A an additive constant and REG the destination
+ register. */
void
-loop_iv_add_mult_sink (loop, b, m, a, reg)
- const struct loop *loop;
- rtx b; /* initial value of basic induction variable */
- rtx m; /* multiplicative constant */
- rtx a; /* additive constant */
- rtx reg; /* destination register */
+loop_iv_add_mult_sink (const struct loop *loop, rtx b, rtx m, rtx a, rtx reg)
{
rtx seq;
update_reg_last_use (b, loop->sink);
update_reg_last_use (m, loop->sink);
- loop_insn_sink (loop, seq);
-
/* It is possible that the expansion created lots of new registers.
- Iterate over the sequence we just created and record them all. */
+ Iterate over the sequence we just created and record them all. We
+ must do this before inserting the sequence. */
loop_regs_update (loop, seq);
+
+ loop_insn_sink (loop, seq);
}
-/* Emit insns after loop to set REG = B * M + A. */
+/* Emit insns after loop to set REG = B * M + A. B is the initial
+ value of the basic induction variable, M a multiplicative constant,
+ A an additive constant and REG the destination register. */
void
-loop_iv_add_mult_hoist (loop, b, m, a, reg)
- const struct loop *loop;
- rtx b; /* initial value of basic induction variable */
- rtx m; /* multiplicative constant */
- rtx a; /* additive constant */
- rtx reg; /* destination register */
+loop_iv_add_mult_hoist (const struct loop *loop, rtx b, rtx m, rtx a, rtx reg)
{
rtx seq;
/* Use copy_rtx to prevent unexpected sharing of these rtx. */
seq = gen_add_mult (copy_rtx (b), copy_rtx (m), copy_rtx (a), reg);
- loop_insn_hoist (loop, seq);
-
/* It is possible that the expansion created lots of new registers.
- Iterate over the sequence we just created and record them all. */
+ Iterate over the sequence we just created and record them all. We
+ must do this before inserting the sequence. */
loop_regs_update (loop, seq);
+
+ loop_insn_hoist (loop, seq);
}
sequence. */
static int
-iv_add_mult_cost (b, m, a, reg)
- rtx b; /* initial value of basic induction variable */
- rtx m; /* multiplicative constant */
- rtx a; /* additive constant */
- rtx reg; /* destination register */
+iv_add_mult_cost (rtx b, rtx m, rtx a, rtx reg)
{
int cost = 0;
rtx last, result;
??? thing, generate wasted RTL just to see if something is possible. */
static int
-product_cheap_p (a, b)
- rtx a;
- rtx b;
+product_cheap_p (rtx a, rtx b)
{
rtx tmp;
int win, n_insns;
final_[bg]iv_value. */
static int
-check_dbra_loop (loop, insn_count)
- struct loop *loop;
- int insn_count;
+check_dbra_loop (struct loop *loop, int insn_count)
{
struct loop_info *loop_info = LOOP_INFO (loop);
struct loop_regs *regs = LOOP_REGS (loop);
struct loop_ivs *ivs = LOOP_IVS (loop);
struct iv_class *bl;
rtx reg;
+ enum machine_mode mode;
rtx jump_label;
rtx final_value;
rtx start_value;
/* Try to compute whether the compare/branch at the loop end is one or
two instructions. */
- get_condition (jump, &first_compare);
+ get_condition (jump, &first_compare, false);
if (first_compare == jump)
compare_and_branch = 1;
else if (first_compare == prev_nonnote_insn (jump))
break;
}
+ /* Try swapping the comparison to identify a suitable biv. */
+ if (!bl)
+ for (bl = ivs->list; bl; bl = bl->next)
+ if (bl->biv_count == 1
+ && ! bl->biv->maybe_multiple
+ && bl->biv->dest_reg == XEXP (comparison, 1)
+ && ! reg_used_between_p (regno_reg_rtx[bl->regno], bl->biv->insn,
+ first_compare))
+ {
+ comparison = gen_rtx_fmt_ee (swap_condition (GET_CODE (comparison)),
+ VOIDmode,
+ XEXP (comparison, 1),
+ XEXP (comparison, 0));
+ break;
+ }
+
if (! bl)
return 0;
In this case, add a reg_note REG_NONNEG, which allows the
m68k DBRA instruction to be used. */
- if (((GET_CODE (comparison) == GT
- && GET_CODE (XEXP (comparison, 1)) == CONST_INT
- && INTVAL (XEXP (comparison, 1)) == -1)
+ if (((GET_CODE (comparison) == GT && XEXP (comparison, 1) == constm1_rtx)
|| (GET_CODE (comparison) == NE && XEXP (comparison, 1) == const0_rtx))
&& GET_CODE (bl->biv->add_val) == CONST_INT
&& INTVAL (bl->biv->add_val) < 0)
&& (INTVAL (bl->initial_value)
% (-INTVAL (bl->biv->add_val))) == 0)
{
- /* register always nonnegative, add REG_NOTE to branch */
+ /* Register always nonnegative, add REG_NOTE to branch. */
if (! find_reg_note (jump, REG_NONNEG, NULL_RTX))
REG_NOTES (jump)
= gen_rtx_EXPR_LIST (REG_NONNEG, bl->biv->dest_reg,
before_comparison = get_condition_for_loop (loop, p);
if (before_comparison
&& XEXP (before_comparison, 0) == bl->biv->dest_reg
- && GET_CODE (before_comparison) == LT
+ && (GET_CODE (before_comparison) == LT
+ || GET_CODE (before_comparison) == LTU)
&& XEXP (before_comparison, 1) == const0_rtx
&& ! reg_set_between_p (bl->biv->dest_reg, p, loop_start)
&& INTVAL (bl->biv->add_val) == -1)
&& REGNO (SET_DEST (set)) == bl->regno)
/* An insn that sets the biv is okay. */
;
- else if ((p == prev_nonnote_insn (prev_nonnote_insn (loop_end))
- || p == prev_nonnote_insn (loop_end))
- && reg_mentioned_p (bivreg, PATTERN (p)))
+ else if (!reg_mentioned_p (bivreg, PATTERN (p)))
+ /* An insn that doesn't mention the biv is okay. */
+ ;
+ else if (p == prev_nonnote_insn (prev_nonnote_insn (loop_end))
+ || p == prev_nonnote_insn (loop_end))
{
/* If either of these insns uses the biv and sets a pseudo
that has more than one usage, then the biv has uses
break;
}
}
- else if (reg_mentioned_p (bivreg, PATTERN (p)))
+ else
{
no_use_except_counting = 0;
break;
/* for constants, LE gets turned into LT */
&& (GET_CODE (comparison) == LT
|| (GET_CODE (comparison) == LE
- && no_use_except_counting)))
+ && no_use_except_counting)
+ || GET_CODE (comparison) == LTU))
{
HOST_WIDE_INT add_val, add_adjust, comparison_val = 0;
rtx initial_value, comparison_value;
/* Save some info needed to produce the new insns. */
reg = bl->biv->dest_reg;
+ mode = GET_MODE (reg);
jump_label = condjump_label (PREV_INSN (loop_end));
new_add_val = GEN_INT (-INTVAL (bl->biv->add_val));
if (initial_value == const0_rtx
&& GET_CODE (comparison_value) == CONST_INT)
{
- start_value = GEN_INT (comparison_val - add_adjust);
+ start_value
+ = gen_int_mode (comparison_val - add_adjust, mode);
loop_insn_hoist (loop, gen_move_insn (reg, start_value));
}
else if (GET_CODE (initial_value) == CONST_INT)
{
- enum machine_mode mode = GET_MODE (reg);
rtx offset = GEN_INT (-INTVAL (initial_value) - add_adjust);
rtx add_insn = gen_add3_insn (reg, comparison_value, offset);
}
else if (! add_adjust)
{
- enum machine_mode mode = GET_MODE (reg);
rtx sub_insn = gen_sub3_insn (reg, comparison_value,
initial_value);
/* Add new compare/branch insn at end of loop. */
start_sequence ();
emit_cmp_and_jump_insns (reg, const0_rtx, cmp_code, NULL_RTX,
- GET_MODE (reg), 0,
+ mode, 0,
XEXP (jump_label, 0));
tem = get_insns ();
end_sequence ();
start of the loop. */
static int
-maybe_eliminate_biv (loop, bl, eliminate_p, threshold, insn_count)
- const struct loop *loop;
- struct iv_class *bl;
- int eliminate_p;
- int threshold, insn_count;
+maybe_eliminate_biv (const struct loop *loop, struct iv_class *bl,
+ int eliminate_p, int threshold, int insn_count)
{
struct loop_ivs *ivs = LOOP_IVS (loop);
rtx reg = bl->biv->dest_reg;
rtx note;
/* If this is a libcall that sets a giv, skip ahead to its end. */
- if (GET_RTX_CLASS (code) == 'i')
+ if (INSN_P (p))
{
note = find_reg_note (p, REG_LIBCALL, NULL_RTX);
Return nonzero if INSN is first. */
int
-loop_insn_first_p (insn, reference)
- rtx insn, reference;
+loop_insn_first_p (rtx insn, rtx reference)
{
rtx p, q;
the offset that we have to take into account due to auto-increment /
div derivation is zero. */
static int
-biv_elimination_giv_has_0_offset (biv, giv, insn)
- struct induction *biv, *giv;
- rtx insn;
+biv_elimination_giv_has_0_offset (struct induction *biv,
+ struct induction *giv, rtx insn)
{
/* If the giv V had the auto-inc address optimization applied
to it, and INSN occurs between the giv insn and the biv
start of the loop (when WHERE_INSN is zero). */
static int
-maybe_eliminate_biv_1 (loop, x, insn, bl, eliminate_p, where_bb, where_insn)
- const struct loop *loop;
- rtx x, insn;
- struct iv_class *bl;
- int eliminate_p;
- basic_block where_bb;
- rtx where_insn;
+maybe_eliminate_biv_1 (const struct loop *loop, rtx x, rtx insn,
+ struct iv_class *bl, int eliminate_p,
+ basic_block where_bb, rtx where_insn)
{
enum rtx_code code = GET_CODE (x);
rtx reg = bl->biv->dest_reg;
is in an insn following INSN in the same basic block. */
static int
-last_use_this_basic_block (reg, insn)
- rtx reg;
- rtx insn;
+last_use_this_basic_block (rtx reg, rtx insn)
{
rtx n;
for (n = insn;
just record the location of the set and process it later. */
static void
-record_initial (dest, set, data)
- rtx dest;
- rtx set;
- void *data ATTRIBUTE_UNUSED;
+record_initial (rtx dest, rtx set, void *data ATTRIBUTE_UNUSED)
{
struct loop_ivs *ivs = (struct loop_ivs *) data;
struct iv_class *bl;
use it. X must be a source expression only. */
static void
-update_reg_last_use (x, insn)
- rtx x;
- rtx insn;
+update_reg_last_use (rtx x, rtx insn)
{
/* Check for the case where INSN does not have a valid luid. In this case,
there is no need to modify the regno_last_uid, as this can only happen
If WANT_REG is nonzero, we wish the condition to be relative to that
register, if possible. Therefore, do not canonicalize the condition
- further. */
+ further. If ALLOW_CC_MODE is nonzero, allow the condition returned
+ to be a compare to a CC mode register. */
rtx
-canonicalize_condition (insn, cond, reverse, earliest, want_reg)
- rtx insn;
- rtx cond;
- int reverse;
- rtx *earliest;
- rtx want_reg;
+canonicalize_condition (rtx insn, rtx cond, int reverse, rtx *earliest,
+ rtx want_reg, int allow_cc_mode)
{
enum rtx_code code;
rtx prev = insn;
the same tests as a function of STORE_FLAG_VALUE as find_comparison_args
in cse.c */
- while (GET_RTX_CLASS (code) == '<'
+ while ((GET_RTX_CLASS (code) == RTX_COMPARE
+ || GET_RTX_CLASS (code) == RTX_COMM_COMPARE)
&& op1 == CONST0_RTX (GET_MODE (op0))
&& op0 != want_reg)
{
REAL_VALUE_NEGATIVE (fsfv)))
#endif
))
- && GET_RTX_CLASS (GET_CODE (SET_SRC (set))) == '<'))
+ && COMPARISON_P (SET_SRC (set))))
&& (((GET_MODE_CLASS (mode) == MODE_CC)
== (GET_MODE_CLASS (inner_mode) == MODE_CC))
|| mode == VOIDmode || inner_mode == VOIDmode))
REAL_VALUE_NEGATIVE (fsfv)))
#endif
))
- && GET_RTX_CLASS (GET_CODE (SET_SRC (set))) == '<'
+ && COMPARISON_P (SET_SRC (set))
&& (((GET_MODE_CLASS (mode) == MODE_CC)
== (GET_MODE_CLASS (inner_mode) == MODE_CC))
|| mode == VOIDmode || inner_mode == VOIDmode))
if (x)
{
- if (GET_RTX_CLASS (GET_CODE (x)) == '<')
+ if (COMPARISON_P (x))
code = GET_CODE (x);
if (reverse_code)
{
/* If OP0 is the result of a comparison, we weren't able to find what
was really being compared, so fail. */
- if (GET_MODE_CLASS (GET_MODE (op0)) == MODE_CC)
+ if (!allow_cc_mode
+ && GET_MODE_CLASS (GET_MODE (op0)) == MODE_CC)
return 0;
/* Canonicalize any ordered comparison with integers involving equality
if we can do computations in the relevant mode and we do not
overflow. */
- if (GET_CODE (op1) == CONST_INT
+ if (GET_MODE_CLASS (GET_MODE (op0)) != MODE_CC
+ && GET_CODE (op1) == CONST_INT
&& GET_MODE (op0) != VOIDmode
&& GET_MODE_BITSIZE (GET_MODE (op0)) <= HOST_BITS_PER_WIDE_INT)
{
}
}
-#ifdef HAVE_cc0
/* Never return CC0; return zero instead. */
- if (op0 == cc0_rtx)
+ if (CC0_P (op0))
return 0;
-#endif
return gen_rtx_fmt_ee (code, VOIDmode, op0, op1);
}
If EARLIEST is nonzero, it is a pointer to a place where the earliest
insn used in locating the condition was found. If a replacement test
of the condition is desired, it should be placed in front of that
- insn and we will be sure that the inputs are still valid. */
+ insn and we will be sure that the inputs are still valid.
+
+ If ALLOW_CC_MODE is nonzero, allow the condition returned to be a
+ compare CC mode register. */
rtx
-get_condition (jump, earliest)
- rtx jump;
- rtx *earliest;
+get_condition (rtx jump, rtx *earliest, int allow_cc_mode)
{
rtx cond;
int reverse;
= GET_CODE (XEXP (SET_SRC (set), 2)) == LABEL_REF
&& XEXP (XEXP (SET_SRC (set), 2), 0) == JUMP_LABEL (jump);
- return canonicalize_condition (jump, cond, reverse, earliest, NULL_RTX);
+ return canonicalize_condition (jump, cond, reverse, earliest, NULL_RTX,
+ allow_cc_mode);
}
/* Similar to above routine, except that we also put an invariant last
unless both operands are invariants. */
rtx
-get_condition_for_loop (loop, x)
- const struct loop *loop;
- rtx x;
+get_condition_for_loop (const struct loop *loop, rtx x)
{
- rtx comparison = get_condition (x, (rtx*) 0);
+ rtx comparison = get_condition (x, (rtx*) 0, false);
if (comparison == 0
|| ! loop_invariant_p (loop, XEXP (comparison, 0))
This is taken mostly from flow.c; similar code exists elsewhere
in the compiler. It may be useful to put this into rtlanal.c. */
static int
-indirect_jump_in_function_p (start)
- rtx start;
+indirect_jump_in_function_p (rtx start)
{
rtx insn;
This function is called from prescan_loop via for_each_rtx. */
static int
-insert_loop_mem (mem, data)
- rtx *mem;
- void *data ATTRIBUTE_UNUSED;
+insert_loop_mem (rtx *mem, void *data ATTRIBUTE_UNUSED)
{
struct loop_info *loop_info = data;
int i;
for (i = 0; i < loop_info->mems_idx; ++i)
if (rtx_equal_p (m, loop_info->mems[i].mem))
{
+ if (MEM_VOLATILE_P (m) && !MEM_VOLATILE_P (loop_info->mems[i].mem))
+ loop_info->mems[i].mem = m;
if (GET_MODE (m) != GET_MODE (loop_info->mems[i].mem))
/* The modes of the two memory accesses are different. If
this happens, something tricky is going on, and we just
else
loop_info->mems_allocated = 32;
- loop_info->mems = (loop_mem_info *)
- xrealloc (loop_info->mems,
- loop_info->mems_allocated * sizeof (loop_mem_info));
+ loop_info->mems = xrealloc (loop_info->mems,
+ loop_info->mems_allocated * sizeof (loop_mem_info));
}
/* Actually insert the MEM. */
optimize register I. */
static void
-loop_regs_scan (loop, extra_size)
- const struct loop *loop;
- int extra_size;
+loop_regs_scan (const struct loop *loop, int extra_size)
{
struct loop_regs *regs = LOOP_REGS (loop);
int old_nregs;
{
regs->size = regs->num + extra_size;
- regs->array = (struct loop_reg *)
- xrealloc (regs->array, regs->size * sizeof (*regs->array));
+ regs->array = xrealloc (regs->array, regs->size * sizeof (*regs->array));
/* Zero the new elements. */
memset (regs->array + old_nregs, 0,
regs->array[i].single_usage = NULL_RTX;
}
- last_set = (rtx *) xcalloc (regs->num, sizeof (rtx));
+ last_set = xcalloc (regs->num, sizeof (rtx));
/* Scan the loop, recording register usage. */
for (insn = loop->top ? loop->top : loop->start; insn != loop->end;
if (GET_CODE (insn) == CALL_INSN)
{
rtx link;
- for (link = CALL_INSN_FUNCTION_USAGE (insn);
- link;
+ for (link = CALL_INSN_FUNCTION_USAGE (insn);
+ link;
link = XEXP (link, 1))
{
rtx op, reg;
/* Returns the number of real INSNs in the LOOP. */
static int
-count_insns_in_loop (loop)
- const struct loop *loop;
+count_insns_in_loop (const struct loop *loop)
{
int count = 0;
rtx insn;
/* Move MEMs into registers for the duration of the loop. */
static void
-load_mems (loop)
- const struct loop *loop;
+load_mems (const struct loop *loop)
{
struct loop_info *loop_info = LOOP_INFO (loop);
struct loop_regs *regs = LOOP_REGS (loop);
;
prev_ebb_head = p;
- cselib_init ();
+ cselib_init (true);
/* Build table of mems that get set to constant values before the
loop. */
else
/* Replace the memory reference with the shadow register. */
replace_loop_mems (p, loop_info->mems[i].mem,
- loop_info->mems[i].reg);
+ loop_info->mems[i].reg, written);
}
if (GET_CODE (p) == CODE_LABEL
}
}
+ /* Now, we need to replace all references to the previous exit
+ label with the new one. */
if (label != NULL_RTX && end_label != NULL_RTX)
- {
- /* Now, we need to replace all references to the previous exit
- label with the new one. */
- rtx_pair rr;
- rr.r1 = end_label;
- rr.r2 = label;
-
- for (p = loop->start; p != loop->end; p = NEXT_INSN (p))
- {
- for_each_rtx (&p, replace_label, &rr);
-
- /* If this is a JUMP_INSN, then we also need to fix the JUMP_LABEL
- field. This is not handled by for_each_rtx because it doesn't
- handle unprinted ('0') fields. We need to update JUMP_LABEL
- because the immediately following unroll pass will use it.
- replace_label would not work anyways, because that only handles
- LABEL_REFs. */
- if (GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) == end_label)
- JUMP_LABEL (p) = label;
- }
- }
+ for (p = loop->start; p != loop->end; p = NEXT_INSN (p))
+ if (GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) == end_label)
+ redirect_jump (p, label, false);
cselib_finish ();
}
/* Called via note_stores, record in SET_SEEN whether X, which is written,
is equal to ARG. */
static void
-note_reg_stored (x, setter, arg)
- rtx x, setter ATTRIBUTE_UNUSED;
- void *arg;
+note_reg_stored (rtx x, rtx setter ATTRIBUTE_UNUSED, void *arg)
{
struct note_reg_stored_arg *t = (struct note_reg_stored_arg *) arg;
if (t->reg == x)
is not used after the loop. */
static void
-try_copy_prop (loop, replacement, regno)
- const struct loop *loop;
- rtx replacement;
- unsigned int regno;
+try_copy_prop (const struct loop *loop, rtx replacement, unsigned int regno)
{
/* This is the reg that we are copying from. */
rtx reg_rtx = regno_reg_rtx[regno];
with NOTE_INSN_DELETED notes. */
static void
-loop_delete_insns (first, last)
- rtx first;
- rtx last;
+loop_delete_insns (rtx first, rtx last)
{
while (1)
{
this pseudo followed immediately by a move insn that sets
REPLACEMENT with REGNO. */
static void
-try_swap_copy_prop (loop, replacement, regno)
- const struct loop *loop;
- rtx replacement;
- unsigned int regno;
+try_swap_copy_prop (const struct loop *loop, rtx replacement,
+ unsigned int regno)
{
rtx insn;
rtx set = NULL_RTX;
}
}
+/* Worker function for find_mem_in_note, called via for_each_rtx. */
+
+static int
+find_mem_in_note_1 (rtx *x, void *data)
+{
+ if (*x != NULL_RTX && GET_CODE (*x) == MEM)
+ {
+ rtx *res = (rtx *) data;
+ *res = *x;
+ return 1;
+ }
+ return 0;
+}
+
+/* Returns the first MEM found in NOTE by depth-first search. */
+
+static rtx
+find_mem_in_note (rtx note)
+{
+ if (note && for_each_rtx (¬e, find_mem_in_note_1, ¬e))
+ return note;
+ return NULL_RTX;
+}
+
/* Replace MEM with its associated pseudo register. This function is
called from load_mems via for_each_rtx. DATA is actually a pointer
to a structure describing the instruction currently being scanned
and the MEM we are currently replacing. */
static int
-replace_loop_mem (mem, data)
- rtx *mem;
- void *data;
+replace_loop_mem (rtx *mem, void *data)
{
loop_replace_args *args = (loop_replace_args *) data;
rtx m = *mem;
}
static void
-replace_loop_mems (insn, mem, reg)
- rtx insn;
- rtx mem;
- rtx reg;
+replace_loop_mems (rtx insn, rtx mem, rtx reg, int written)
{
loop_replace_args args;
args.replacement = reg;
for_each_rtx (&insn, replace_loop_mem, &args);
+
+ /* If we hoist a mem write out of the loop, then REG_EQUAL
+ notes referring to the mem are no longer valid. */
+ if (written)
+ {
+ rtx note, sub;
+ rtx *link;
+
+ for (link = ®_NOTES (insn); (note = *link); link = &XEXP (note, 1))
+ {
+ if (REG_NOTE_KIND (note) == REG_EQUAL
+ && (sub = find_mem_in_note (note))
+ && true_dependence (mem, VOIDmode, sub, rtx_varies_p))
+ {
+ /* Remove the note. */
+ validate_change (NULL_RTX, link, XEXP (note, 1), 1);
+ break;
+ }
+ }
+ }
}
/* Replace one register with another. Called through for_each_rtx; PX points
a structure of arguments. */
static int
-replace_loop_reg (px, data)
- rtx *px;
- void *data;
+replace_loop_reg (rtx *px, void *data)
{
rtx x = *px;
loop_replace_args *args = (loop_replace_args *) data;
}
static void
-replace_loop_regs (insn, reg, replacement)
- rtx insn;
- rtx reg;
- rtx replacement;
+replace_loop_regs (rtx insn, rtx reg, rtx replacement)
{
loop_replace_args args;
for_each_rtx (&insn, replace_loop_reg, &args);
}
-
-/* Replace occurrences of the old exit label for the loop with the new
- one. DATA is an rtx_pair containing the old and new labels,
- respectively. */
-
-static int
-replace_label (x, data)
- rtx *x;
- void *data;
-{
- rtx l = *x;
- rtx old_label = ((rtx_pair *) data)->r1;
- rtx new_label = ((rtx_pair *) data)->r2;
-
- if (l == NULL_RTX)
- return 0;
-
- if (GET_CODE (l) != LABEL_REF)
- return 0;
-
- if (XEXP (l, 0) != old_label)
- return 0;
-
- XEXP (l, 0) = new_label;
- ++LABEL_NUSES (new_label);
- --LABEL_NUSES (old_label);
-
- return 0;
-}
\f
/* Emit insn for PATTERN after WHERE_INSN in basic block WHERE_BB
(ignored in the interim). */
static rtx
-loop_insn_emit_after (loop, where_bb, where_insn, pattern)
- const struct loop *loop ATTRIBUTE_UNUSED;
- basic_block where_bb ATTRIBUTE_UNUSED;
- rtx where_insn;
- rtx pattern;
+loop_insn_emit_after (const struct loop *loop ATTRIBUTE_UNUSED,
+ basic_block where_bb ATTRIBUTE_UNUSED, rtx where_insn,
+ rtx pattern)
{
return emit_insn_after (pattern, where_insn);
}
otherwise hoist PATTERN into the loop pre-header. */
rtx
-loop_insn_emit_before (loop, where_bb, where_insn, pattern)
- const struct loop *loop;
- basic_block where_bb ATTRIBUTE_UNUSED;
- rtx where_insn;
- rtx pattern;
+loop_insn_emit_before (const struct loop *loop,
+ basic_block where_bb ATTRIBUTE_UNUSED,
+ rtx where_insn, rtx pattern)
{
if (! where_insn)
return loop_insn_hoist (loop, pattern);
WHERE_BB (ignored in the interim) within the loop. */
static rtx
-loop_call_insn_emit_before (loop, where_bb, where_insn, pattern)
- const struct loop *loop ATTRIBUTE_UNUSED;
- basic_block where_bb ATTRIBUTE_UNUSED;
- rtx where_insn;
- rtx pattern;
+loop_call_insn_emit_before (const struct loop *loop ATTRIBUTE_UNUSED,
+ basic_block where_bb ATTRIBUTE_UNUSED,
+ rtx where_insn, rtx pattern)
{
return emit_call_insn_before (pattern, where_insn);
}
/* Hoist insn for PATTERN into the loop pre-header. */
rtx
-loop_insn_hoist (loop, pattern)
- const struct loop *loop;
- rtx pattern;
+loop_insn_hoist (const struct loop *loop, rtx pattern)
{
return loop_insn_emit_before (loop, 0, loop->start, pattern);
}
/* Hoist call insn for PATTERN into the loop pre-header. */
static rtx
-loop_call_insn_hoist (loop, pattern)
- const struct loop *loop;
- rtx pattern;
+loop_call_insn_hoist (const struct loop *loop, rtx pattern)
{
return loop_call_insn_emit_before (loop, 0, loop->start, pattern);
}
/* Sink insn for PATTERN after the loop end. */
rtx
-loop_insn_sink (loop, pattern)
- const struct loop *loop;
- rtx pattern;
+loop_insn_sink (const struct loop *loop, rtx pattern)
{
return loop_insn_emit_before (loop, 0, loop->sink, pattern);
}
-/* bl->final_value can be eighter general_operand or PLUS of general_operand
- and constant. Emit sequence of intructions to load it into REG */
+/* bl->final_value can be either general_operand or PLUS of general_operand
+ and constant. Emit sequence of instructions to load it into REG. */
static rtx
-gen_load_of_final_value (reg, final_value)
- rtx reg, final_value;
+gen_load_of_final_value (rtx reg, rtx final_value)
{
rtx seq;
start_sequence ();
since this is slightly more efficient. */
static rtx
-loop_insn_sink_or_swim (loop, pattern)
- const struct loop *loop;
- rtx pattern;
+loop_insn_sink_or_swim (const struct loop *loop, rtx pattern)
{
if (loop->exit_count)
return loop_insn_hoist (loop, pattern);
}
\f
static void
-loop_ivs_dump (loop, file, verbose)
- const struct loop *loop;
- FILE *file;
- int verbose;
+loop_ivs_dump (const struct loop *loop, FILE *file, int verbose)
{
struct iv_class *bl;
int iv_num = 0;
static void
-loop_iv_class_dump (bl, file, verbose)
- const struct iv_class *bl;
- FILE *file;
- int verbose ATTRIBUTE_UNUSED;
+loop_iv_class_dump (const struct iv_class *bl, FILE *file,
+ int verbose ATTRIBUTE_UNUSED)
{
struct induction *v;
rtx incr;
static void
-loop_biv_dump (v, file, verbose)
- const struct induction *v;
- FILE *file;
- int verbose;
+loop_biv_dump (const struct induction *v, FILE *file, int verbose)
{
if (! v || ! file)
return;
static void
-loop_giv_dump (v, file, verbose)
- const struct induction *v;
- FILE *file;
- int verbose;
+loop_giv_dump (const struct induction *v, FILE *file, int verbose)
{
if (! v || ! file)
return;
void
-debug_ivs (loop)
- const struct loop *loop;
+debug_ivs (const struct loop *loop)
{
loop_ivs_dump (loop, stderr, 1);
}
void
-debug_iv_class (bl)
- const struct iv_class *bl;
+debug_iv_class (const struct iv_class *bl)
{
loop_iv_class_dump (bl, stderr, 1);
}
void
-debug_biv (v)
- const struct induction *v;
+debug_biv (const struct induction *v)
{
loop_biv_dump (v, stderr, 1);
}
void
-debug_giv (v)
- const struct induction *v;
+debug_giv (const struct induction *v)
{
loop_giv_dump (v, stderr, 1);
}
#define LOOP_INSN_UID(INSN) ((INSN) ? INSN_UID (INSN) : -1)
static void
-loop_dump_aux (loop, file, verbose)
- const struct loop *loop;
- FILE *file;
- int verbose ATTRIBUTE_UNUSED;
+loop_dump_aux (const struct loop *loop, FILE *file,
+ int verbose ATTRIBUTE_UNUSED)
{
rtx label;
/* Print diagnostics to compare our concept of a loop with
what the loop notes say. */
- if (! PREV_INSN (loop->first->head)
- || GET_CODE (PREV_INSN (loop->first->head)) != NOTE
- || NOTE_LINE_NUMBER (PREV_INSN (loop->first->head))
+ if (! PREV_INSN (BB_HEAD (loop->first))
+ || GET_CODE (PREV_INSN (BB_HEAD (loop->first))) != NOTE
+ || NOTE_LINE_NUMBER (PREV_INSN (BB_HEAD (loop->first)))
!= NOTE_INSN_LOOP_BEG)
fprintf (file, ";; No NOTE_INSN_LOOP_BEG at %d\n",
- INSN_UID (PREV_INSN (loop->first->head)));
- if (! NEXT_INSN (loop->last->end)
- || GET_CODE (NEXT_INSN (loop->last->end)) != NOTE
- || NOTE_LINE_NUMBER (NEXT_INSN (loop->last->end))
+ INSN_UID (PREV_INSN (BB_HEAD (loop->first))));
+ if (! NEXT_INSN (BB_END (loop->last))
+ || GET_CODE (NEXT_INSN (BB_END (loop->last))) != NOTE
+ || NOTE_LINE_NUMBER (NEXT_INSN (BB_END (loop->last)))
!= NOTE_INSN_LOOP_END)
fprintf (file, ";; No NOTE_INSN_LOOP_END at %d\n",
- INSN_UID (NEXT_INSN (loop->last->end)));
+ INSN_UID (NEXT_INSN (BB_END (loop->last))));
if (loop->start)
{
/* Call this function from the debugger to dump LOOP. */
void
-debug_loop (loop)
- const struct loop *loop;
+debug_loop (const struct loop *loop)
{
flow_loop_dump (loop, stderr, loop_dump_aux, 1);
}
/* Call this function from the debugger to dump LOOPS. */
void
-debug_loops (loops)
- const struct loops *loops;
+debug_loops (const struct loops *loops)
{
flow_loops_dump (loops, stderr, loop_dump_aux, 1);
}
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