/* Control flow optimization code for GNU compiler.
- Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2010
- Free Software Foundation, Inc.
+ Copyright (C) 1987-2016 Free Software Foundation, Inc.
This file is part of GCC.
#include "config.h"
#include "system.h"
#include "coretypes.h"
-#include "tm.h"
+#include "backend.h"
+#include "target.h"
#include "rtl.h"
-#include "hard-reg-set.h"
-#include "regs.h"
-#include "timevar.h"
-#include "output.h"
+#include "tree.h"
+#include "cfghooks.h"
+#include "df.h"
+#include "tm_p.h"
#include "insn-config.h"
-#include "flags.h"
-#include "recog.h"
-#include "diagnostic-core.h"
+#include "emit-rtl.h"
#include "cselib.h"
#include "params.h"
-#include "tm_p.h"
-#include "target.h"
-#include "cfglayout.h"
-#include "emit-rtl.h"
#include "tree-pass.h"
#include "cfgloop.h"
-#include "expr.h"
-#include "df.h"
+#include "cfgrtl.h"
+#include "cfganal.h"
+#include "cfgbuild.h"
+#include "cfgcleanup.h"
#include "dce.h"
#include "dbgcnt.h"
+#include "rtl-iter.h"
#define FORWARDER_BLOCK_P(BB) ((BB)->flags & BB_FORWARDER_BLOCK)
/* Set to true when we are running first pass of try_optimize_cfg loop. */
static bool first_pass;
-/* Set to true if crossjumps occured in the latest run of try_optimize_cfg. */
+/* Set to true if crossjumps occurred in the latest run of try_optimize_cfg. */
static bool crossjumps_occured;
-static bool try_crossjump_to_edge (int, edge, edge);
+/* Set to true if we couldn't run an optimization due to stale liveness
+ information; we should run df_analyze to enable more opportunities. */
+static bool block_was_dirty;
+
+static bool try_crossjump_to_edge (int, edge, edge, enum replace_direction);
static bool try_crossjump_bb (int, basic_block);
static bool outgoing_edges_match (int, basic_block, basic_block);
-static bool old_insns_match_p (int, rtx, rtx);
+static enum replace_direction old_insns_match_p (int, rtx_insn *, rtx_insn *);
static void merge_blocks_move_predecessor_nojumps (basic_block, basic_block);
static void merge_blocks_move_successor_nojumps (basic_block, basic_block);
static bool mark_effect (rtx, bitmap);
static void notice_new_block (basic_block);
static void update_forwarder_flag (basic_block);
-static int mentions_nonequal_regs (rtx *, void *);
static void merge_memattrs (rtx, rtx);
\f
/* Set flags for newly created block. */
{
basic_block jump_block, jump_dest_block, cbranch_dest_block;
edge cbranch_jump_edge, cbranch_fallthru_edge;
- rtx cbranch_insn;
+ rtx_insn *cbranch_insn;
/* Verify that there are exactly two successors. */
if (EDGE_COUNT (cbranch_block->succs) != 2)
unconditional jump. */
jump_block = cbranch_fallthru_edge->dest;
if (!single_pred_p (jump_block)
- || jump_block->next_bb == EXIT_BLOCK_PTR
+ || jump_block->next_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
|| !FORWARDER_BLOCK_P (jump_block))
return false;
jump_dest_block = single_succ (jump_block);
unconditional branch. */
cbranch_dest_block = cbranch_jump_edge->dest;
- if (cbranch_dest_block == EXIT_BLOCK_PTR
+ if (cbranch_dest_block == EXIT_BLOCK_PTR_FOR_FN (cfun)
|| !can_fallthru (jump_block, cbranch_dest_block))
return false;
/* Invert the conditional branch. */
- if (!invert_jump (cbranch_insn, block_label (jump_dest_block), 0))
+ if (!invert_jump (as_a <rtx_jump_insn *> (cbranch_insn),
+ block_label (jump_dest_block), 0))
return false;
if (dump_file)
static bool
mark_effect (rtx exp, regset nonequal)
{
- int regno;
rtx dest;
switch (GET_CODE (exp))
{
/* In case we do clobber the register, mark it as equal, as we know the
value is dead so it don't have to match. */
case CLOBBER:
- if (REG_P (XEXP (exp, 0)))
- {
- dest = XEXP (exp, 0);
- regno = REGNO (dest);
- CLEAR_REGNO_REG_SET (nonequal, regno);
- if (regno < FIRST_PSEUDO_REGISTER)
- {
- int n = hard_regno_nregs[regno][GET_MODE (dest)];
- while (--n > 0)
- CLEAR_REGNO_REG_SET (nonequal, regno + n);
- }
- }
+ dest = XEXP (exp, 0);
+ if (REG_P (dest))
+ bitmap_clear_range (nonequal, REGNO (dest), REG_NREGS (dest));
return false;
case SET:
return false;
if (!REG_P (dest))
return true;
- regno = REGNO (dest);
- SET_REGNO_REG_SET (nonequal, regno);
- if (regno < FIRST_PSEUDO_REGISTER)
- {
- int n = hard_regno_nregs[regno][GET_MODE (dest)];
- while (--n > 0)
- SET_REGNO_REG_SET (nonequal, regno + n);
- }
+ bitmap_set_range (nonequal, REGNO (dest), REG_NREGS (dest));
return false;
default:
}
}
-/* Return nonzero if X is a register set in regset DATA.
- Called via for_each_rtx. */
-static int
-mentions_nonequal_regs (rtx *x, void *data)
+/* Return true if X contains a register in NONEQUAL. */
+static bool
+mentions_nonequal_regs (const_rtx x, regset nonequal)
{
- regset nonequal = (regset) data;
- if (REG_P (*x))
+ subrtx_iterator::array_type array;
+ FOR_EACH_SUBRTX (iter, array, x, NONCONST)
{
- int regno;
-
- regno = REGNO (*x);
- if (REGNO_REG_SET_P (nonequal, regno))
- return 1;
- if (regno < FIRST_PSEUDO_REGISTER)
+ const_rtx x = *iter;
+ if (REG_P (x))
{
- int n = hard_regno_nregs[regno][GET_MODE (*x)];
- while (--n > 0)
- if (REGNO_REG_SET_P (nonequal, regno + n))
- return 1;
+ unsigned int end_regno = END_REGNO (x);
+ for (unsigned int regno = REGNO (x); regno < end_regno; ++regno)
+ if (REGNO_REG_SET_P (nonequal, regno))
+ return true;
}
}
- return 0;
+ return false;
}
+
/* Attempt to prove that the basic block B will have no side effects and
always continues in the same edge if reached via E. Return the edge
if exist, NULL otherwise. */
static edge
thread_jump (edge e, basic_block b)
{
- rtx set1, set2, cond1, cond2, insn;
+ rtx set1, set2, cond1, cond2;
+ rtx_insn *insn;
enum rtx_code code1, code2, reversed_code2;
bool reverse1 = false;
unsigned i;
/* cond2 must not mention any register that is not equal to the
former block. */
- if (for_each_rtx (&cond2, mentions_nonequal_regs, nonequal))
+ if (mentions_nonequal_regs (cond2, nonequal))
goto failed_exit;
EXECUTE_IF_SET_IN_REG_SET (nonequal, 0, i, rsi)
partition boundaries). See the comments at the top of
bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
- if (find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX))
+ if (JUMP_P (BB_END (b)) && CROSSING_JUMP_P (BB_END (b)))
return false;
for (ei = ei_start (b->succs); (e = ei_safe_edge (ei)); )
{
basic_block target, first;
- int counter, goto_locus;
+ location_t goto_locus;
+ int counter;
bool threaded = false;
int nthreaded_edges = 0;
- bool may_thread = first_pass | df_get_bb_dirty (b);
+ bool may_thread = first_pass || (b->flags & BB_MODIFIED) != 0;
/* Skip complex edges because we don't know how to update them.
bb-reorder.c:partition_hot_cold_basic_blocks for complete
details. */
- if (first != EXIT_BLOCK_PTR
- && find_reg_note (BB_END (first), REG_CROSSING_JUMP, NULL_RTX))
- return false;
+ if (first != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && JUMP_P (BB_END (first))
+ && CROSSING_JUMP_P (BB_END (first)))
+ return changed;
- while (counter < n_basic_blocks)
+ while (counter < n_basic_blocks_for_fn (cfun))
{
basic_block new_target = NULL;
bool new_target_threaded = false;
- may_thread |= df_get_bb_dirty (target);
+ may_thread |= (target->flags & BB_MODIFIED) != 0;
if (FORWARDER_BLOCK_P (target)
&& !(single_succ_edge (target)->flags & EDGE_CROSSING)
- && single_succ (target) != EXIT_BLOCK_PTR)
+ && single_succ (target) != EXIT_BLOCK_PTR_FOR_FN (cfun))
{
/* Bypass trivial infinite loops. */
new_target = single_succ (target);
if (target == new_target)
- counter = n_basic_blocks;
+ counter = n_basic_blocks_for_fn (cfun);
else if (!optimize)
{
/* When not optimizing, ensure that edges or forwarder
blocks with different locus are not optimized out. */
- int new_locus = single_succ_edge (target)->goto_locus;
- int locus = goto_locus;
+ location_t new_locus = single_succ_edge (target)->goto_locus;
+ location_t locus = goto_locus;
- if (new_locus && locus && !locator_eq (new_locus, locus))
+ if (LOCATION_LOCUS (new_locus) != UNKNOWN_LOCATION
+ && LOCATION_LOCUS (locus) != UNKNOWN_LOCATION
+ && new_locus != locus)
new_target = NULL;
else
{
- rtx last;
-
- if (new_locus)
+ if (LOCATION_LOCUS (new_locus) != UNKNOWN_LOCATION)
locus = new_locus;
- last = BB_END (target);
+ rtx_insn *last = BB_END (target);
if (DEBUG_INSN_P (last))
last = prev_nondebug_insn (last);
+ if (last && INSN_P (last))
+ new_locus = INSN_LOCATION (last);
+ else
+ new_locus = UNKNOWN_LOCATION;
- new_locus = last && INSN_P (last)
- ? INSN_LOCATOR (last) : 0;
-
- if (new_locus && locus && !locator_eq (new_locus, locus))
+ if (LOCATION_LOCUS (new_locus) != UNKNOWN_LOCATION
+ && LOCATION_LOCUS (locus) != UNKNOWN_LOCATION
+ && new_locus != locus)
new_target = NULL;
else
{
- if (new_locus)
+ if (LOCATION_LOCUS (new_locus) != UNKNOWN_LOCATION)
locus = new_locus;
goto_locus = locus;
if (t)
{
if (!threaded_edges)
- threaded_edges = XNEWVEC (edge, n_basic_blocks);
+ threaded_edges = XNEWVEC (edge,
+ n_basic_blocks_for_fn (cfun));
else
{
int i;
break;
if (i < nthreaded_edges)
{
- counter = n_basic_blocks;
+ counter = n_basic_blocks_for_fn (cfun);
break;
}
}
if (t->dest == b)
break;
- gcc_assert (nthreaded_edges < n_basic_blocks - NUM_FIXED_BLOCKS);
+ gcc_assert (nthreaded_edges
+ < (n_basic_blocks_for_fn (cfun)
+ - NUM_FIXED_BLOCKS));
threaded_edges[nthreaded_edges++] = t;
new_target = t->dest;
threaded |= new_target_threaded;
}
- if (counter >= n_basic_blocks)
+ if (counter >= n_basic_blocks_for_fn (cfun))
{
if (dump_file)
fprintf (dump_file, "Infinite loop in BB %i.\n",
e->goto_locus = goto_locus;
/* Don't force if target is exit block. */
- if (threaded && target != EXIT_BLOCK_PTR)
+ if (threaded && target != EXIT_BLOCK_PTR_FOR_FN (cfun))
{
notice_new_block (redirect_edge_and_branch_force (e, target));
if (dump_file)
/* We successfully forwarded the edge. Now update profile
data: for each edge we traversed in the chain, remove
the original edge's execution count. */
- edge_frequency = ((edge_probability * b->frequency
- + REG_BR_PROB_BASE / 2)
- / REG_BR_PROB_BASE);
-
- if (!FORWARDER_BLOCK_P (b) && forwarder_block_p (b))
- b->flags |= BB_FORWARDER_BLOCK;
+ edge_frequency = apply_probability (b->frequency, edge_probability);
do
{
ei_next (&ei);
}
- if (threaded_edges)
- free (threaded_edges);
+ free (threaded_edges);
return changed;
}
\f
static void
merge_blocks_move_predecessor_nojumps (basic_block a, basic_block b)
{
- rtx barrier;
+ rtx_insn *barrier;
/* If we are partitioning hot/cold basic blocks, we don't want to
mess up unconditional or indirect jumps that cross between hot
static void
merge_blocks_move_successor_nojumps (basic_block a, basic_block b)
{
- rtx barrier, real_b_end;
- rtx label, table;
+ rtx_insn *barrier, *real_b_end;
+ rtx label;
+ rtx_jump_table_data *table;
/* If we are partitioning hot/cold basic blocks, we don't want to
mess up unconditional or indirect jumps that cross between hot
if (e->flags & EDGE_FALLTHRU)
{
int b_index = b->index, c_index = c->index;
+
+ /* Protect the loop latches. */
+ if (current_loops && c->loop_father->latch == c)
+ return NULL;
+
merge_blocks (b, c);
update_forwarder_flag (b);
fprintf (dump_file, "Merged %d and %d without moving.\n",
b_index, c_index);
- return b->prev_bb == ENTRY_BLOCK_PTR ? b : b->prev_bb;
+ return b->prev_bb == ENTRY_BLOCK_PTR_FOR_FN (cfun) ? b : b->prev_bb;
}
/* Otherwise we will need to move code around. Do that only if expensive
if (! c_has_outgoing_fallthru)
{
merge_blocks_move_successor_nojumps (b, c);
- return next == ENTRY_BLOCK_PTR ? next->next_bb : next;
+ return next == ENTRY_BLOCK_PTR_FOR_FN (cfun) ? next->next_bb : next;
}
/* If B does not have an incoming fallthru, then it can be moved
{
basic_block bb;
- if (b_fallthru_edge->src == ENTRY_BLOCK_PTR)
+ if (b_fallthru_edge->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
return NULL;
bb = force_nonfallthru (b_fallthru_edge);
if (bb)
}
merge_blocks_move_predecessor_nojumps (b, c);
- return next == ENTRY_BLOCK_PTR ? next->next_bb : next;
+ return next == ENTRY_BLOCK_PTR_FOR_FN (cfun) ? next->next_bb : next;
}
return NULL;
/* Removes the memory attributes of MEM expression
if they are not equal. */
-void
+static void
merge_memattrs (rtx x, rtx y)
{
int i;
if (GET_MODE (x) != GET_MODE (y))
return;
- if (code == MEM && MEM_ATTRS (x) != MEM_ATTRS (y))
+ if (code == MEM && !mem_attrs_eq_p (MEM_ATTRS (x), MEM_ATTRS (y)))
{
if (! MEM_ATTRS (x))
MEM_ATTRS (y) = 0;
MEM_ATTRS (x) = 0;
else
{
- rtx mem_size;
+ HOST_WIDE_INT mem_size;
if (MEM_ALIAS_SET (x) != MEM_ALIAS_SET (y))
{
{
set_mem_expr (x, 0);
set_mem_expr (y, 0);
- set_mem_offset (x, 0);
- set_mem_offset (y, 0);
+ clear_mem_offset (x);
+ clear_mem_offset (y);
}
- else if (MEM_OFFSET (x) != MEM_OFFSET (y))
+ else if (MEM_OFFSET_KNOWN_P (x) != MEM_OFFSET_KNOWN_P (y)
+ || (MEM_OFFSET_KNOWN_P (x)
+ && MEM_OFFSET (x) != MEM_OFFSET (y)))
{
- set_mem_offset (x, 0);
- set_mem_offset (y, 0);
+ clear_mem_offset (x);
+ clear_mem_offset (y);
}
- if (!MEM_SIZE (x))
- mem_size = NULL_RTX;
- else if (!MEM_SIZE (y))
- mem_size = NULL_RTX;
+ if (MEM_SIZE_KNOWN_P (x) && MEM_SIZE_KNOWN_P (y))
+ {
+ mem_size = MAX (MEM_SIZE (x), MEM_SIZE (y));
+ set_mem_size (x, mem_size);
+ set_mem_size (y, mem_size);
+ }
else
- mem_size = GEN_INT (MAX (INTVAL (MEM_SIZE (x)),
- INTVAL (MEM_SIZE (y))));
- set_mem_size (x, mem_size);
- set_mem_size (y, mem_size);
+ {
+ clear_mem_size (x);
+ clear_mem_size (y);
+ }
set_mem_align (x, MIN (MEM_ALIGN (x), MEM_ALIGN (y)));
set_mem_align (y, MEM_ALIGN (x));
}
}
+ if (code == MEM)
+ {
+ if (MEM_READONLY_P (x) != MEM_READONLY_P (y))
+ {
+ MEM_READONLY_P (x) = 0;
+ MEM_READONLY_P (y) = 0;
+ }
+ if (MEM_NOTRAP_P (x) != MEM_NOTRAP_P (y))
+ {
+ MEM_NOTRAP_P (x) = 0;
+ MEM_NOTRAP_P (y) = 0;
+ }
+ if (MEM_VOLATILE_P (x) != MEM_VOLATILE_P (y))
+ {
+ MEM_VOLATILE_P (x) = 1;
+ MEM_VOLATILE_P (y) = 1;
+ }
+ }
fmt = GET_RTX_FORMAT (code);
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
}
-/* Return true if I1 and I2 are equivalent and thus can be crossjumped. */
+ /* Checks if patterns P1 and P2 are equivalent, apart from the possibly
+ different single sets S1 and S2. */
static bool
-old_insns_match_p (int mode ATTRIBUTE_UNUSED, rtx i1, rtx i2)
+equal_different_set_p (rtx p1, rtx s1, rtx p2, rtx s2)
+{
+ int i;
+ rtx e1, e2;
+
+ if (p1 == s1 && p2 == s2)
+ return true;
+
+ if (GET_CODE (p1) != PARALLEL || GET_CODE (p2) != PARALLEL)
+ return false;
+
+ if (XVECLEN (p1, 0) != XVECLEN (p2, 0))
+ return false;
+
+ for (i = 0; i < XVECLEN (p1, 0); i++)
+ {
+ e1 = XVECEXP (p1, 0, i);
+ e2 = XVECEXP (p2, 0, i);
+ if (e1 == s1 && e2 == s2)
+ continue;
+ if (reload_completed
+ ? rtx_renumbered_equal_p (e1, e2) : rtx_equal_p (e1, e2))
+ continue;
+
+ return false;
+ }
+
+ return true;
+}
+
+
+/* NOTE1 is the REG_EQUAL note, if any, attached to an insn
+ that is a single_set with a SET_SRC of SRC1. Similarly
+ for NOTE2/SRC2.
+
+ So effectively NOTE1/NOTE2 are an alternate form of
+ SRC1/SRC2 respectively.
+
+ Return nonzero if SRC1 or NOTE1 has the same constant
+ integer value as SRC2 or NOTE2. Else return zero. */
+static int
+values_equal_p (rtx note1, rtx note2, rtx src1, rtx src2)
+{
+ if (note1
+ && note2
+ && CONST_INT_P (XEXP (note1, 0))
+ && rtx_equal_p (XEXP (note1, 0), XEXP (note2, 0)))
+ return 1;
+
+ if (!note1
+ && !note2
+ && CONST_INT_P (src1)
+ && CONST_INT_P (src2)
+ && rtx_equal_p (src1, src2))
+ return 1;
+
+ if (note1
+ && CONST_INT_P (src2)
+ && rtx_equal_p (XEXP (note1, 0), src2))
+ return 1;
+
+ if (note2
+ && CONST_INT_P (src1)
+ && rtx_equal_p (XEXP (note2, 0), src1))
+ return 1;
+
+ return 0;
+}
+
+/* Examine register notes on I1 and I2 and return:
+ - dir_forward if I1 can be replaced by I2, or
+ - dir_backward if I2 can be replaced by I1, or
+ - dir_both if both are the case. */
+
+static enum replace_direction
+can_replace_by (rtx_insn *i1, rtx_insn *i2)
+{
+ rtx s1, s2, d1, d2, src1, src2, note1, note2;
+ bool c1, c2;
+
+ /* Check for 2 sets. */
+ s1 = single_set (i1);
+ s2 = single_set (i2);
+ if (s1 == NULL_RTX || s2 == NULL_RTX)
+ return dir_none;
+
+ /* Check that the 2 sets set the same dest. */
+ d1 = SET_DEST (s1);
+ d2 = SET_DEST (s2);
+ if (!(reload_completed
+ ? rtx_renumbered_equal_p (d1, d2) : rtx_equal_p (d1, d2)))
+ return dir_none;
+
+ /* Find identical req_equiv or reg_equal note, which implies that the 2 sets
+ set dest to the same value. */
+ note1 = find_reg_equal_equiv_note (i1);
+ note2 = find_reg_equal_equiv_note (i2);
+
+ src1 = SET_SRC (s1);
+ src2 = SET_SRC (s2);
+
+ if (!values_equal_p (note1, note2, src1, src2))
+ return dir_none;
+
+ if (!equal_different_set_p (PATTERN (i1), s1, PATTERN (i2), s2))
+ return dir_none;
+
+ /* Although the 2 sets set dest to the same value, we cannot replace
+ (set (dest) (const_int))
+ by
+ (set (dest) (reg))
+ because we don't know if the reg is live and has the same value at the
+ location of replacement. */
+ c1 = CONST_INT_P (src1);
+ c2 = CONST_INT_P (src2);
+ if (c1 && c2)
+ return dir_both;
+ else if (c2)
+ return dir_forward;
+ else if (c1)
+ return dir_backward;
+
+ return dir_none;
+}
+
+/* Merges directions A and B. */
+
+static enum replace_direction
+merge_dir (enum replace_direction a, enum replace_direction b)
+{
+ /* Implements the following table:
+ |bo fw bw no
+ ---+-----------
+ bo |bo fw bw no
+ fw |-- fw no no
+ bw |-- -- bw no
+ no |-- -- -- no. */
+
+ if (a == b)
+ return a;
+
+ if (a == dir_both)
+ return b;
+ if (b == dir_both)
+ return a;
+
+ return dir_none;
+}
+
+/* Examine I1 and I2 and return:
+ - dir_forward if I1 can be replaced by I2, or
+ - dir_backward if I2 can be replaced by I1, or
+ - dir_both if both are the case. */
+
+static enum replace_direction
+old_insns_match_p (int mode ATTRIBUTE_UNUSED, rtx_insn *i1, rtx_insn *i2)
{
rtx p1, p2;
/* Verify that I1 and I2 are equivalent. */
if (GET_CODE (i1) != GET_CODE (i2))
- return false;
+ return dir_none;
/* __builtin_unreachable() may lead to empty blocks (ending with
NOTE_INSN_BASIC_BLOCK). They may be crossjumped. */
if (NOTE_INSN_BASIC_BLOCK_P (i1) && NOTE_INSN_BASIC_BLOCK_P (i2))
- return true;
+ return dir_both;
+
+ /* ??? Do not allow cross-jumping between different stack levels. */
+ p1 = find_reg_note (i1, REG_ARGS_SIZE, NULL);
+ p2 = find_reg_note (i2, REG_ARGS_SIZE, NULL);
+ if (p1 && p2)
+ {
+ p1 = XEXP (p1, 0);
+ p2 = XEXP (p2, 0);
+ if (!rtx_equal_p (p1, p2))
+ return dir_none;
+
+ /* ??? Worse, this adjustment had better be constant lest we
+ have differing incoming stack levels. */
+ if (!frame_pointer_needed
+ && find_args_size_adjust (i1) == HOST_WIDE_INT_MIN)
+ return dir_none;
+ }
+ else if (p1 || p2)
+ return dir_none;
p1 = PATTERN (i1);
p2 = PATTERN (i2);
if (GET_CODE (p1) != GET_CODE (p2))
- return false;
+ return dir_none;
/* If this is a CALL_INSN, compare register usage information.
If we don't check this on stack register machines, the two
rtx n2 = find_reg_note (i2, REG_EH_REGION, 0);
if (!n1 && n2)
- return false;
+ return dir_none;
if (n1 && (!n2 || XEXP (n1, 0) != XEXP (n2, 0)))
- return false;
+ return dir_none;
if (!rtx_equal_p (CALL_INSN_FUNCTION_USAGE (i1),
CALL_INSN_FUNCTION_USAGE (i2))
|| SIBLING_CALL_P (i1) != SIBLING_CALL_P (i2))
- return false;
+ return dir_none;
+
+ /* For address sanitizer, never crossjump __asan_report_* builtins,
+ otherwise errors might be reported on incorrect lines. */
+ if (flag_sanitize & SANITIZE_ADDRESS)
+ {
+ rtx call = get_call_rtx_from (i1);
+ if (call && GET_CODE (XEXP (XEXP (call, 0), 0)) == SYMBOL_REF)
+ {
+ rtx symbol = XEXP (XEXP (call, 0), 0);
+ if (SYMBOL_REF_DECL (symbol)
+ && TREE_CODE (SYMBOL_REF_DECL (symbol)) == FUNCTION_DECL)
+ {
+ if ((DECL_BUILT_IN_CLASS (SYMBOL_REF_DECL (symbol))
+ == BUILT_IN_NORMAL)
+ && DECL_FUNCTION_CODE (SYMBOL_REF_DECL (symbol))
+ >= BUILT_IN_ASAN_REPORT_LOAD1
+ && DECL_FUNCTION_CODE (SYMBOL_REF_DECL (symbol))
+ <= BUILT_IN_ASAN_STOREN)
+ return dir_none;
+ }
+ }
+ }
}
#ifdef STACK_REGS
SET_HARD_REG_BIT (i2_regset, REGNO (XEXP (note, 0)));
if (!hard_reg_set_equal_p (i1_regset, i2_regset))
- return false;
+ return dir_none;
}
#endif
if (reload_completed
? rtx_renumbered_equal_p (p1, p2) : rtx_equal_p (p1, p2))
- return true;
+ return dir_both;
- return false;
+ return can_replace_by (i1, i2);
}
\f
/* When comparing insns I1 and I2 in flow_find_cross_jump or
flow_find_head_matching_sequence, ensure the notes match. */
static void
-merge_notes (rtx i1, rtx i2)
+merge_notes (rtx_insn *i1, rtx_insn *i2)
{
/* If the merged insns have different REG_EQUAL notes, then
remove them. */
}
}
+ /* Walks from I1 in BB1 backward till the next non-debug insn, and returns the
+ resulting insn in I1, and the corresponding bb in BB1. At the head of a
+ bb, if there is a predecessor bb that reaches this bb via fallthru, and
+ FOLLOW_FALLTHRU, walks further in the predecessor bb and registers this in
+ DID_FALLTHRU. Otherwise, stops at the head of the bb. */
+
+static void
+walk_to_nondebug_insn (rtx_insn **i1, basic_block *bb1, bool follow_fallthru,
+ bool *did_fallthru)
+{
+ edge fallthru;
+
+ *did_fallthru = false;
+
+ /* Ignore notes. */
+ while (!NONDEBUG_INSN_P (*i1))
+ {
+ if (*i1 != BB_HEAD (*bb1))
+ {
+ *i1 = PREV_INSN (*i1);
+ continue;
+ }
+
+ if (!follow_fallthru)
+ return;
+
+ fallthru = find_fallthru_edge ((*bb1)->preds);
+ if (!fallthru || fallthru->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ || !single_succ_p (fallthru->src))
+ return;
+
+ *bb1 = fallthru->src;
+ *i1 = BB_END (*bb1);
+ *did_fallthru = true;
+ }
+}
+
/* Look through the insns at the end of BB1 and BB2 and find the longest
- sequence that are equivalent. Store the first insns for that sequence
- in *F1 and *F2 and return the sequence length.
+ sequence that are either equivalent, or allow forward or backward
+ replacement. Store the first insns for that sequence in *F1 and *F2 and
+ return the sequence length.
+
+ DIR_P indicates the allowed replacement direction on function entry, and
+ the actual replacement direction on function exit. If NULL, only equivalent
+ sequences are allowed.
To simplify callers of this function, if the blocks match exactly,
store the head of the blocks in *F1 and *F2. */
int
-flow_find_cross_jump (basic_block bb1, basic_block bb2, rtx *f1, rtx *f2)
+flow_find_cross_jump (basic_block bb1, basic_block bb2, rtx_insn **f1,
+ rtx_insn **f2, enum replace_direction *dir_p)
{
- rtx i1, i2, last1, last2, afterlast1, afterlast2;
+ rtx_insn *i1, *i2, *last1, *last2, *afterlast1, *afterlast2;
int ninsns = 0;
+ enum replace_direction dir, last_dir, afterlast_dir;
+ bool follow_fallthru, did_fallthru;
+
+ if (dir_p)
+ dir = *dir_p;
+ else
+ dir = dir_both;
+ afterlast_dir = dir;
+ last_dir = afterlast_dir;
/* Skip simple jumps at the end of the blocks. Complex jumps still
need to be compared for equivalence, which we'll do below. */
i1 = BB_END (bb1);
- last1 = afterlast1 = last2 = afterlast2 = NULL_RTX;
+ last1 = afterlast1 = last2 = afterlast2 = NULL;
if (onlyjump_p (i1)
|| (returnjump_p (i1) && !side_effects_p (PATTERN (i1))))
{
|| (returnjump_p (i2) && !side_effects_p (PATTERN (i2))))
{
last2 = i2;
- /* Count everything except for unconditional jump as insn. */
- if (!simplejump_p (i2) && !returnjump_p (i2) && last1)
+ /* Count everything except for unconditional jump as insn.
+ Don't count any jumps if dir_p is NULL. */
+ if (!simplejump_p (i2) && !returnjump_p (i2) && last1 && dir_p)
ninsns++;
i2 = PREV_INSN (i2);
}
while (true)
{
- /* Ignore notes. */
- while (!NONDEBUG_INSN_P (i1) && i1 != BB_HEAD (bb1))
- i1 = PREV_INSN (i1);
-
- while (!NONDEBUG_INSN_P (i2) && i2 != BB_HEAD (bb2))
- i2 = PREV_INSN (i2);
+ /* In the following example, we can replace all jumps to C by jumps to A.
+
+ This removes 4 duplicate insns.
+ [bb A] insn1 [bb C] insn1
+ insn2 insn2
+ [bb B] insn3 insn3
+ insn4 insn4
+ jump_insn jump_insn
+
+ We could also replace all jumps to A by jumps to C, but that leaves B
+ alive, and removes only 2 duplicate insns. In a subsequent crossjump
+ step, all jumps to B would be replaced with jumps to the middle of C,
+ achieving the same result with more effort.
+ So we allow only the first possibility, which means that we don't allow
+ fallthru in the block that's being replaced. */
+
+ follow_fallthru = dir_p && dir != dir_forward;
+ walk_to_nondebug_insn (&i1, &bb1, follow_fallthru, &did_fallthru);
+ if (did_fallthru)
+ dir = dir_backward;
+
+ follow_fallthru = dir_p && dir != dir_backward;
+ walk_to_nondebug_insn (&i2, &bb2, follow_fallthru, &did_fallthru);
+ if (did_fallthru)
+ dir = dir_forward;
if (i1 == BB_HEAD (bb1) || i2 == BB_HEAD (bb2))
break;
- if (!old_insns_match_p (0, i1, i2))
+ dir = merge_dir (dir, old_insns_match_p (0, i1, i2));
+ if (dir == dir_none || (!dir_p && dir != dir_both))
break;
merge_memattrs (i1, i2);
afterlast1 = last1, afterlast2 = last2;
last1 = i1, last2 = i2;
- ninsns++;
+ afterlast_dir = last_dir;
+ last_dir = dir;
+ if (active_insn_p (i1))
+ ninsns++;
}
i1 = PREV_INSN (i1);
i2 = PREV_INSN (i2);
}
-#ifdef HAVE_cc0
/* Don't allow the insn after a compare to be shared by
cross-jumping unless the compare is also shared. */
- if (ninsns && reg_mentioned_p (cc0_rtx, last1) && ! sets_cc0_p (last1))
- last1 = afterlast1, last2 = afterlast2, ninsns--;
-#endif
+ if (HAVE_cc0 && ninsns && reg_mentioned_p (cc0_rtx, last1)
+ && ! sets_cc0_p (last1))
+ last1 = afterlast1, last2 = afterlast2, last_dir = afterlast_dir, ninsns--;
/* Include preceding notes and labels in the cross-jump. One,
this may bring us to the head of the blocks as requested above.
Two, it keeps line number notes as matched as may be. */
if (ninsns)
{
+ bb1 = BLOCK_FOR_INSN (last1);
while (last1 != BB_HEAD (bb1) && !NONDEBUG_INSN_P (PREV_INSN (last1)))
last1 = PREV_INSN (last1);
if (last1 != BB_HEAD (bb1) && LABEL_P (PREV_INSN (last1)))
last1 = PREV_INSN (last1);
+ bb2 = BLOCK_FOR_INSN (last2);
while (last2 != BB_HEAD (bb2) && !NONDEBUG_INSN_P (PREV_INSN (last2)))
last2 = PREV_INSN (last2);
*f2 = last2;
}
+ if (dir_p)
+ *dir_p = last_dir;
return ninsns;
}
/* Like flow_find_cross_jump, except start looking for a matching sequence from
the head of the two blocks. Do not include jumps at the end.
If STOP_AFTER is nonzero, stop after finding that many matching
- instructions. */
+ instructions. If STOP_AFTER is zero, count all INSN_P insns, if it is
+ non-zero, only count active insns. */
int
-flow_find_head_matching_sequence (basic_block bb1, basic_block bb2, rtx *f1,
- rtx *f2, int stop_after)
+flow_find_head_matching_sequence (basic_block bb1, basic_block bb2, rtx_insn **f1,
+ rtx_insn **f2, int stop_after)
{
- rtx i1, i2, last1, last2, beforelast1, beforelast2;
+ rtx_insn *i1, *i2, *last1, *last2, *beforelast1, *beforelast2;
int ninsns = 0;
edge e;
edge_iterator ei;
i1 = BB_HEAD (bb1);
i2 = BB_HEAD (bb2);
- last1 = beforelast1 = last2 = beforelast2 = NULL_RTX;
+ last1 = beforelast1 = last2 = beforelast2 = NULL;
while (true)
{
- /* Ignore notes. */
+ /* Ignore notes, except NOTE_INSN_EPILOGUE_BEG. */
while (!NONDEBUG_INSN_P (i1) && i1 != BB_END (bb1))
- i1 = NEXT_INSN (i1);
+ {
+ if (NOTE_P (i1) && NOTE_KIND (i1) == NOTE_INSN_EPILOGUE_BEG)
+ break;
+ i1 = NEXT_INSN (i1);
+ }
while (!NONDEBUG_INSN_P (i2) && i2 != BB_END (bb2))
- i2 = NEXT_INSN (i2);
+ {
+ if (NOTE_P (i2) && NOTE_KIND (i2) == NOTE_INSN_EPILOGUE_BEG)
+ break;
+ i2 = NEXT_INSN (i2);
+ }
if ((i1 == BB_END (bb1) && !NONDEBUG_INSN_P (i1))
|| (i2 == BB_END (bb2) && !NONDEBUG_INSN_P (i2)))
&& nehedges1 != nehedges2))
break;
- if (!old_insns_match_p (0, i1, i2))
+ if (old_insns_match_p (0, i1, i2) != dir_both)
break;
merge_memattrs (i1, i2);
beforelast1 = last1, beforelast2 = last2;
last1 = i1, last2 = i2;
- ninsns++;
+ if (!stop_after || active_insn_p (i1))
+ ninsns++;
}
if (i1 == BB_END (bb1) || i2 == BB_END (bb2)
i2 = NEXT_INSN (i2);
}
-#ifdef HAVE_cc0
/* Don't allow a compare to be shared by cross-jumping unless the insn
after the compare is also shared. */
- if (ninsns && reg_mentioned_p (cc0_rtx, last1) && sets_cc0_p (last1))
+ if (HAVE_cc0 && ninsns && reg_mentioned_p (cc0_rtx, last1)
+ && sets_cc0_p (last1))
last1 = beforelast1, last2 = beforelast2, ninsns--;
-#endif
if (ninsns)
{
edge e1, e2;
edge_iterator ei;
+ /* If we performed shrink-wrapping, edges to the exit block can
+ only be distinguished for JUMP_INSNs. The two paths may differ in
+ whether they went through the prologue. Sibcalls are fine, we know
+ that we either didn't need or inserted an epilogue before them. */
+ if (crtl->shrink_wrapped
+ && single_succ_p (bb1)
+ && single_succ (bb1) == EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && !JUMP_P (BB_END (bb1))
+ && !(CALL_P (BB_END (bb1)) && SIBLING_CALL_P (BB_END (bb1))))
+ return false;
+
/* If BB1 has only one successor, we may be looking at either an
unconditional jump, or a fake edge to exit. */
if (single_succ_p (bb1)
Return true if they are identical. */
{
rtx label1, label2;
- rtx table1, table2;
+ rtx_jump_table_data *table1, *table2;
if (tablejump_p (BB_END (bb1), &label1, &table1)
&& tablejump_p (BB_END (bb2), &label2, &table2)
if (identical)
{
- replace_label_data rr;
bool match;
/* Temporarily replace references to LABEL1 with LABEL2
in BB1->END so that we could compare the instructions. */
- rr.r1 = label1;
- rr.r2 = label2;
- rr.update_label_nuses = false;
- for_each_rtx (&BB_END (bb1), replace_label, &rr);
+ replace_label_in_insn (BB_END (bb1), label1, label2, false);
- match = old_insns_match_p (mode, BB_END (bb1), BB_END (bb2));
+ match = (old_insns_match_p (mode, BB_END (bb1), BB_END (bb2))
+ == dir_both);
if (dump_file && match)
fprintf (dump_file,
"Tablejumps in bb %i and %i match.\n",
/* Set the original label in BB1->END because when deleting
a block whose end is a tablejump, the tablejump referenced
from the instruction is deleted too. */
- rr.r1 = label2;
- rr.r2 = label1;
- for_each_rtx (&BB_END (bb1), replace_label, &rr);
+ replace_label_in_insn (BB_END (bb1), label2, label1, false);
return match;
}
}
}
+ /* Find the last non-debug non-note instruction in each bb, except
+ stop when we see the NOTE_INSN_BASIC_BLOCK, as old_insns_match_p
+ handles that case specially. old_insns_match_p does not handle
+ other types of instruction notes. */
+ rtx_insn *last1 = BB_END (bb1);
+ rtx_insn *last2 = BB_END (bb2);
+ while (!NOTE_INSN_BASIC_BLOCK_P (last1) &&
+ (DEBUG_INSN_P (last1) || NOTE_P (last1)))
+ last1 = PREV_INSN (last1);
+ while (!NOTE_INSN_BASIC_BLOCK_P (last2) &&
+ (DEBUG_INSN_P (last2) || NOTE_P (last2)))
+ last2 = PREV_INSN (last2);
+ gcc_assert (last1 && last2);
+
/* First ensure that the instructions match. There may be many outgoing
edges so this test is generally cheaper. */
- if (!old_insns_match_p (mode, BB_END (bb1), BB_END (bb2)))
+ if (old_insns_match_p (mode, last1, last2) != dir_both)
return false;
/* Search the outgoing edges, ensure that the counts do match, find possible
if (EDGE_COUNT (bb1->succs) != EDGE_COUNT (bb2->succs))
return false;
+ bool nonfakeedges = false;
FOR_EACH_EDGE (e1, ei, bb1->succs)
{
e2 = EDGE_SUCC (bb2, ei.index);
+ if ((e1->flags & EDGE_FAKE) == 0)
+ nonfakeedges = true;
+
if (e1->flags & EDGE_EH)
nehedges1++;
|| (fallthru1 != 0) != (fallthru2 != 0))
return false;
+ /* If !ACCUMULATE_OUTGOING_ARGS, bb1 (and bb2) have no successors
+ and the last real insn doesn't have REG_ARGS_SIZE note, don't
+ attempt to optimize, as the two basic blocks might have different
+ REG_ARGS_SIZE depths. For noreturn calls and unconditional
+ traps there should be REG_ARG_SIZE notes, they could be missing
+ for __builtin_unreachable () uses though. */
+ if (!nonfakeedges
+ && !ACCUMULATE_OUTGOING_ARGS
+ && (!INSN_P (last1)
+ || !find_reg_note (last1, REG_ARGS_SIZE, NULL)))
+ return false;
+
/* fallthru edges must be forwarded to the same destination. */
if (fallthru1)
{
/* E1 and E2 are edges with the same destination block. Search their
predecessors for common code. If found, redirect control flow from
- (maybe the middle of) E1->SRC to (maybe the middle of) E2->SRC. */
+ (maybe the middle of) E1->SRC to (maybe the middle of) E2->SRC (dir_forward),
+ or the other way around (dir_backward). DIR specifies the allowed
+ replacement direction. */
static bool
-try_crossjump_to_edge (int mode, edge e1, edge e2)
+try_crossjump_to_edge (int mode, edge e1, edge e2,
+ enum replace_direction dir)
{
int nmatch;
basic_block src1 = e1->src, src2 = e2->src;
basic_block redirect_to, redirect_from, to_remove;
- rtx newpos1, newpos2;
+ basic_block osrc1, osrc2, redirect_edges_to, tmp;
+ rtx_insn *newpos1, *newpos2;
edge s;
edge_iterator ei;
- newpos1 = newpos2 = NULL_RTX;
+ newpos1 = newpos2 = NULL;
/* If we have partitioned hot/cold basic blocks, it is a bad idea
to try this optimization.
partition boundaries). See the comments at the top of
bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
- if (flag_reorder_blocks_and_partition && reload_completed)
+ if (crtl->has_bb_partition && reload_completed)
return false;
/* Search backward through forwarder blocks. We don't need to worry
e2 = single_pred_edge (src2), src2 = e2->src;
/* Nothing to do if we reach ENTRY, or a common source block. */
- if (src1 == ENTRY_BLOCK_PTR || src2 == ENTRY_BLOCK_PTR)
+ if (src1 == ENTRY_BLOCK_PTR_FOR_FN (cfun) || src2
+ == ENTRY_BLOCK_PTR_FOR_FN (cfun))
return false;
if (src1 == src2)
return false;
return false;
/* ... and part the second. */
- nmatch = flow_find_cross_jump (src1, src2, &newpos1, &newpos2);
+ nmatch = flow_find_cross_jump (src1, src2, &newpos1, &newpos2, &dir);
+
+ osrc1 = src1;
+ osrc2 = src2;
+ if (newpos1 != NULL_RTX)
+ src1 = BLOCK_FOR_INSN (newpos1);
+ if (newpos2 != NULL_RTX)
+ src2 = BLOCK_FOR_INSN (newpos2);
+
+ if (dir == dir_backward)
+ {
+#define SWAP(T, X, Y) do { T tmp = (X); (X) = (Y); (Y) = tmp; } while (0)
+ SWAP (basic_block, osrc1, osrc2);
+ SWAP (basic_block, src1, src2);
+ SWAP (edge, e1, e2);
+ SWAP (rtx_insn *, newpos1, newpos2);
+#undef SWAP
+ }
/* Don't proceed with the crossjump unless we found a sufficient number
of matching instructions or the 'from' block was totally matched
If we have tablejumps in the end of SRC1 and SRC2
they have been already compared for equivalence in outgoing_edges_match ()
so replace the references to TABLE1 by references to TABLE2. */
- {
+ {
rtx label1, label2;
- rtx table1, table2;
+ rtx_jump_table_data *table1, *table2;
- if (tablejump_p (BB_END (src1), &label1, &table1)
- && tablejump_p (BB_END (src2), &label2, &table2)
+ if (tablejump_p (BB_END (osrc1), &label1, &table1)
+ && tablejump_p (BB_END (osrc2), &label2, &table2)
&& label1 != label2)
{
- replace_label_data rr;
- rtx insn;
+ rtx_insn *insn;
/* Replace references to LABEL1 with LABEL2. */
- rr.r1 = label1;
- rr.r2 = label2;
- rr.update_label_nuses = true;
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
{
/* Do not replace the label in SRC1->END because when deleting
a block whose end is a tablejump, the tablejump referenced
from the instruction is deleted too. */
- if (insn != BB_END (src1))
- for_each_rtx (&insn, replace_label, &rr);
+ if (insn != BB_END (osrc1))
+ replace_label_in_insn (insn, label1, label2, true);
}
}
- }
+ }
/* Avoid splitting if possible. We must always split when SRC2 has
EH predecessor edges, or we may end up with basic blocks with both
/* We may have some registers visible through the block. */
df_set_bb_dirty (redirect_to);
+ if (osrc2 == src2)
+ redirect_edges_to = redirect_to;
+ else
+ redirect_edges_to = osrc2;
+
/* Recompute the frequencies and counts of outgoing edges. */
- FOR_EACH_EDGE (s, ei, redirect_to->succs)
+ FOR_EACH_EDGE (s, ei, redirect_edges_to->succs)
{
edge s2;
edge_iterator ei;
s2->dest->count = 0;
}
- if (!redirect_to->frequency && !src1->frequency)
+ if (!redirect_edges_to->frequency && !src1->frequency)
s->probability = (s->probability + s2->probability) / 2;
else
s->probability
- = ((s->probability * redirect_to->frequency +
+ = ((s->probability * redirect_edges_to->frequency +
s2->probability * src1->frequency)
- / (redirect_to->frequency + src1->frequency));
+ / (redirect_edges_to->frequency + src1->frequency));
}
/* Adjust count and frequency for the block. An earlier jump
threading pass may have left the profile in an inconsistent
state (see update_bb_profile_for_threading) so we must be
prepared for overflows. */
- redirect_to->count += src1->count;
- redirect_to->frequency += src1->frequency;
- if (redirect_to->frequency > BB_FREQ_MAX)
- redirect_to->frequency = BB_FREQ_MAX;
- update_br_prob_note (redirect_to);
+ tmp = redirect_to;
+ do
+ {
+ tmp->count += src1->count;
+ tmp->frequency += src1->frequency;
+ if (tmp->frequency > BB_FREQ_MAX)
+ tmp->frequency = BB_FREQ_MAX;
+ if (tmp == redirect_edges_to)
+ break;
+ tmp = find_fallthru_edge (tmp->succs)->dest;
+ }
+ while (true);
+ update_br_prob_note (redirect_edges_to);
/* Edit SRC1 to go to REDIRECT_TO at NEWPOS1. */
edge e, e2, fallthru;
bool changed;
unsigned max, ix, ix2;
- basic_block ev, ev2;
/* Nothing to do if there is not at least two incoming edges. */
if (EDGE_COUNT (bb->preds) < 2)
/* Don't crossjump if this block ends in a computed jump,
unless we are optimizing for size. */
if (optimize_bb_for_size_p (bb)
- && bb != EXIT_BLOCK_PTR
+ && bb != EXIT_BLOCK_PTR_FOR_FN (cfun)
&& computed_jump_p (BB_END (bb)))
return false;
fallthru = find_fallthru_edge (bb->preds);
changed = false;
- for (ix = 0, ev = bb; ix < EDGE_COUNT (ev->preds); )
+ for (ix = 0; ix < EDGE_COUNT (bb->preds);)
{
- e = EDGE_PRED (ev, ix);
+ e = EDGE_PRED (bb, ix);
ix++;
/* As noted above, first try with the fallthru predecessor (or, a
/* If nothing changed since the last attempt, there is nothing
we can do. */
if (!first_pass
- && (!(df_get_bb_dirty (e->src))
- && !(df_get_bb_dirty (fallthru->src))))
+ && !((e->src->flags & BB_MODIFIED)
+ || (fallthru->src->flags & BB_MODIFIED)))
continue;
- if (try_crossjump_to_edge (mode, e, fallthru))
+ if (try_crossjump_to_edge (mode, e, fallthru, dir_forward))
{
changed = true;
ix = 0;
- ev = bb;
continue;
}
}
if (EDGE_SUCC (e->src, 0) != e)
continue;
- for (ix2 = 0, ev2 = bb; ix2 < EDGE_COUNT (ev2->preds); )
+ for (ix2 = 0; ix2 < EDGE_COUNT (bb->preds); ix2++)
{
- e2 = EDGE_PRED (ev2, ix2);
- ix2++;
+ e2 = EDGE_PRED (bb, ix2);
if (e2 == e)
continue;
/* If nothing changed since the last attempt, there is nothing
we can do. */
if (!first_pass
- && (!(df_get_bb_dirty (e->src))
- && !(df_get_bb_dirty (e2->src))))
+ && !((e->src->flags & BB_MODIFIED)
+ || (e2->src->flags & BB_MODIFIED)))
continue;
- if (try_crossjump_to_edge (mode, e, e2))
+ /* Both e and e2 are not fallthru edges, so we can crossjump in either
+ direction. */
+ if (try_crossjump_to_edge (mode, e, e2, dir_both))
{
changed = true;
- ev2 = bb;
ix = 0;
break;
}
return changed;
}
+/* Search the successors of BB for common insn sequences. When found,
+ share code between them by moving it across the basic block
+ boundary. Return true if any changes made. */
+
+static bool
+try_head_merge_bb (basic_block bb)
+{
+ basic_block final_dest_bb = NULL;
+ int max_match = INT_MAX;
+ edge e0;
+ rtx_insn **headptr, **currptr, **nextptr;
+ bool changed, moveall;
+ unsigned ix;
+ rtx_insn *e0_last_head;
+ rtx cond;
+ rtx_insn *move_before;
+ unsigned nedges = EDGE_COUNT (bb->succs);
+ rtx_insn *jump = BB_END (bb);
+ regset live, live_union;
+
+ /* Nothing to do if there is not at least two outgoing edges. */
+ if (nedges < 2)
+ return false;
+
+ /* Don't crossjump if this block ends in a computed jump,
+ unless we are optimizing for size. */
+ if (optimize_bb_for_size_p (bb)
+ && bb != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && computed_jump_p (BB_END (bb)))
+ return false;
+
+ cond = get_condition (jump, &move_before, true, false);
+ if (cond == NULL_RTX)
+ {
+ if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, jump))
+ move_before = prev_nonnote_nondebug_insn (jump);
+ else
+ move_before = jump;
+ }
+
+ for (ix = 0; ix < nedges; ix++)
+ if (EDGE_SUCC (bb, ix)->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return false;
+
+ for (ix = 0; ix < nedges; ix++)
+ {
+ edge e = EDGE_SUCC (bb, ix);
+ basic_block other_bb = e->dest;
+
+ if (df_get_bb_dirty (other_bb))
+ {
+ block_was_dirty = true;
+ return false;
+ }
+
+ if (e->flags & EDGE_ABNORMAL)
+ return false;
+
+ /* Normally, all destination blocks must only be reachable from this
+ block, i.e. they must have one incoming edge.
+
+ There is one special case we can handle, that of multiple consecutive
+ jumps where the first jumps to one of the targets of the second jump.
+ This happens frequently in switch statements for default labels.
+ The structure is as follows:
+ FINAL_DEST_BB
+ ....
+ if (cond) jump A;
+ fall through
+ BB
+ jump with targets A, B, C, D...
+ A
+ has two incoming edges, from FINAL_DEST_BB and BB
+
+ In this case, we can try to move the insns through BB and into
+ FINAL_DEST_BB. */
+ if (EDGE_COUNT (other_bb->preds) != 1)
+ {
+ edge incoming_edge, incoming_bb_other_edge;
+ edge_iterator ei;
+
+ if (final_dest_bb != NULL
+ || EDGE_COUNT (other_bb->preds) != 2)
+ return false;
+
+ /* We must be able to move the insns across the whole block. */
+ move_before = BB_HEAD (bb);
+ while (!NONDEBUG_INSN_P (move_before))
+ move_before = NEXT_INSN (move_before);
+
+ if (EDGE_COUNT (bb->preds) != 1)
+ return false;
+ incoming_edge = EDGE_PRED (bb, 0);
+ final_dest_bb = incoming_edge->src;
+ if (EDGE_COUNT (final_dest_bb->succs) != 2)
+ return false;
+ FOR_EACH_EDGE (incoming_bb_other_edge, ei, final_dest_bb->succs)
+ if (incoming_bb_other_edge != incoming_edge)
+ break;
+ if (incoming_bb_other_edge->dest != other_bb)
+ return false;
+ }
+ }
+
+ e0 = EDGE_SUCC (bb, 0);
+ e0_last_head = NULL;
+ changed = false;
+
+ for (ix = 1; ix < nedges; ix++)
+ {
+ edge e = EDGE_SUCC (bb, ix);
+ rtx_insn *e0_last, *e_last;
+ int nmatch;
+
+ nmatch = flow_find_head_matching_sequence (e0->dest, e->dest,
+ &e0_last, &e_last, 0);
+ if (nmatch == 0)
+ return false;
+
+ if (nmatch < max_match)
+ {
+ max_match = nmatch;
+ e0_last_head = e0_last;
+ }
+ }
+
+ /* If we matched an entire block, we probably have to avoid moving the
+ last insn. */
+ if (max_match > 0
+ && e0_last_head == BB_END (e0->dest)
+ && (find_reg_note (e0_last_head, REG_EH_REGION, 0)
+ || control_flow_insn_p (e0_last_head)))
+ {
+ max_match--;
+ if (max_match == 0)
+ return false;
+ do
+ e0_last_head = prev_real_insn (e0_last_head);
+ while (DEBUG_INSN_P (e0_last_head));
+ }
+
+ if (max_match == 0)
+ return false;
+
+ /* We must find a union of the live registers at each of the end points. */
+ live = BITMAP_ALLOC (NULL);
+ live_union = BITMAP_ALLOC (NULL);
+
+ currptr = XNEWVEC (rtx_insn *, nedges);
+ headptr = XNEWVEC (rtx_insn *, nedges);
+ nextptr = XNEWVEC (rtx_insn *, nedges);
+
+ for (ix = 0; ix < nedges; ix++)
+ {
+ int j;
+ basic_block merge_bb = EDGE_SUCC (bb, ix)->dest;
+ rtx_insn *head = BB_HEAD (merge_bb);
+
+ while (!NONDEBUG_INSN_P (head))
+ head = NEXT_INSN (head);
+ headptr[ix] = head;
+ currptr[ix] = head;
+
+ /* Compute the end point and live information */
+ for (j = 1; j < max_match; j++)
+ do
+ head = NEXT_INSN (head);
+ while (!NONDEBUG_INSN_P (head));
+ simulate_backwards_to_point (merge_bb, live, head);
+ IOR_REG_SET (live_union, live);
+ }
+
+ /* If we're moving across two blocks, verify the validity of the
+ first move, then adjust the target and let the loop below deal
+ with the final move. */
+ if (final_dest_bb != NULL)
+ {
+ rtx_insn *move_upto;
+
+ moveall = can_move_insns_across (currptr[0], e0_last_head, move_before,
+ jump, e0->dest, live_union,
+ NULL, &move_upto);
+ if (!moveall)
+ {
+ if (move_upto == NULL_RTX)
+ goto out;
+
+ while (e0_last_head != move_upto)
+ {
+ df_simulate_one_insn_backwards (e0->dest, e0_last_head,
+ live_union);
+ e0_last_head = PREV_INSN (e0_last_head);
+ }
+ }
+ if (e0_last_head == NULL_RTX)
+ goto out;
+
+ jump = BB_END (final_dest_bb);
+ cond = get_condition (jump, &move_before, true, false);
+ if (cond == NULL_RTX)
+ {
+ if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, jump))
+ move_before = prev_nonnote_nondebug_insn (jump);
+ else
+ move_before = jump;
+ }
+ }
+
+ do
+ {
+ rtx_insn *move_upto;
+ moveall = can_move_insns_across (currptr[0], e0_last_head,
+ move_before, jump, e0->dest, live_union,
+ NULL, &move_upto);
+ if (!moveall && move_upto == NULL_RTX)
+ {
+ if (jump == move_before)
+ break;
+
+ /* Try again, using a different insertion point. */
+ move_before = jump;
+
+ /* Don't try moving before a cc0 user, as that may invalidate
+ the cc0. */
+ if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, jump))
+ break;
+
+ continue;
+ }
+
+ if (final_dest_bb && !moveall)
+ /* We haven't checked whether a partial move would be OK for the first
+ move, so we have to fail this case. */
+ break;
+
+ changed = true;
+ for (;;)
+ {
+ if (currptr[0] == move_upto)
+ break;
+ for (ix = 0; ix < nedges; ix++)
+ {
+ rtx_insn *curr = currptr[ix];
+ do
+ curr = NEXT_INSN (curr);
+ while (!NONDEBUG_INSN_P (curr));
+ currptr[ix] = curr;
+ }
+ }
+
+ /* If we can't currently move all of the identical insns, remember
+ each insn after the range that we'll merge. */
+ if (!moveall)
+ for (ix = 0; ix < nedges; ix++)
+ {
+ rtx_insn *curr = currptr[ix];
+ do
+ curr = NEXT_INSN (curr);
+ while (!NONDEBUG_INSN_P (curr));
+ nextptr[ix] = curr;
+ }
+
+ reorder_insns (headptr[0], currptr[0], PREV_INSN (move_before));
+ df_set_bb_dirty (EDGE_SUCC (bb, 0)->dest);
+ if (final_dest_bb != NULL)
+ df_set_bb_dirty (final_dest_bb);
+ df_set_bb_dirty (bb);
+ for (ix = 1; ix < nedges; ix++)
+ {
+ df_set_bb_dirty (EDGE_SUCC (bb, ix)->dest);
+ delete_insn_chain (headptr[ix], currptr[ix], false);
+ }
+ if (!moveall)
+ {
+ if (jump == move_before)
+ break;
+
+ /* For the unmerged insns, try a different insertion point. */
+ move_before = jump;
+
+ /* Don't try moving before a cc0 user, as that may invalidate
+ the cc0. */
+ if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, jump))
+ break;
+
+ for (ix = 0; ix < nedges; ix++)
+ currptr[ix] = headptr[ix] = nextptr[ix];
+ }
+ }
+ while (!moveall);
+
+ out:
+ free (currptr);
+ free (headptr);
+ free (nextptr);
+
+ crossjumps_occured |= changed;
+
+ return changed;
+}
+
/* Return true if BB contains just bb note, or bb note followed
by only DEBUG_INSNs. */
static bool
trivially_empty_bb_p (basic_block bb)
{
- rtx insn = BB_END (bb);
+ rtx_insn *insn = BB_END (bb);
while (1)
{
crossjumps_occured = false;
- FOR_EACH_BB (bb)
+ FOR_EACH_BB_FN (bb, cfun)
update_forwarder_flag (bb);
if (! targetm.cannot_modify_jumps_p ())
one predecessor, they may be combined. */
do
{
+ block_was_dirty = false;
changed = false;
iterations++;
"\n\ntry_optimize_cfg iteration %i\n\n",
iterations);
- for (b = ENTRY_BLOCK_PTR->next_bb; b != EXIT_BLOCK_PTR;)
+ for (b = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; b
+ != EXIT_BLOCK_PTR_FOR_FN (cfun);)
{
basic_block c;
edge s;
if (EDGE_COUNT (b->preds) == 0
|| (EDGE_COUNT (b->succs) == 0
&& trivially_empty_bb_p (b)
- && single_succ_edge (ENTRY_BLOCK_PTR)->dest != b))
+ && single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun))->dest
+ != b))
{
c = b->prev_bb;
if (EDGE_COUNT (b->preds) > 0)
if (current_ir_type () == IR_RTL_CFGLAYOUT)
{
- if (b->il.rtl->footer
- && BARRIER_P (b->il.rtl->footer))
+ if (BB_FOOTER (b)
+ && BARRIER_P (BB_FOOTER (b)))
FOR_EACH_EDGE (e, ei, b->preds)
if ((e->flags & EDGE_FALLTHRU)
- && e->src->il.rtl->footer == NULL)
+ && BB_FOOTER (e->src) == NULL)
{
- if (b->il.rtl->footer)
+ if (BB_FOOTER (b))
{
- e->src->il.rtl->footer = b->il.rtl->footer;
- b->il.rtl->footer = NULL;
+ BB_FOOTER (e->src) = BB_FOOTER (b);
+ BB_FOOTER (b) = NULL;
}
else
{
start_sequence ();
- e->src->il.rtl->footer = emit_barrier ();
+ BB_FOOTER (e->src) = emit_barrier ();
end_sequence ();
}
}
}
else
{
- rtx last = get_last_bb_insn (b);
+ rtx_insn *last = get_last_bb_insn (b);
if (last && BARRIER_P (last))
FOR_EACH_EDGE (e, ei, b->preds)
if ((e->flags & EDGE_FALLTHRU))
}
}
delete_basic_block (b);
- if (!(mode & CLEANUP_CFGLAYOUT))
- changed = true;
- /* Avoid trying to remove ENTRY_BLOCK_PTR. */
- b = (c == ENTRY_BLOCK_PTR ? c->next_bb : c);
+ changed = true;
+ /* Avoid trying to remove the exit block. */
+ b = (c == ENTRY_BLOCK_PTR_FOR_FN (cfun) ? c->next_bb : c);
continue;
}
&& (single_pred_edge (b)->flags & EDGE_FALLTHRU)
&& !(single_pred_edge (b)->flags & EDGE_COMPLEX)
&& LABEL_P (BB_HEAD (b))
+ && !LABEL_PRESERVE_P (BB_HEAD (b))
/* If the previous block ends with a branch to this
block, we can't delete the label. Normally this
is a condjump that is yet to be simplified, but
if CASE_DROPS_THRU, this can be a tablejump with
some element going to the same place as the
default (fallthru). */
- && (single_pred (b) == ENTRY_BLOCK_PTR
+ && (single_pred (b) == ENTRY_BLOCK_PTR_FOR_FN (cfun)
|| !JUMP_P (BB_END (single_pred (b)))
|| ! label_is_jump_target_p (BB_HEAD (b),
BB_END (single_pred (b)))))
{
- rtx label = BB_HEAD (b);
-
- delete_insn_chain (label, label, false);
- /* If the case label is undeletable, move it after the
- BASIC_BLOCK note. */
- if (NOTE_KIND (BB_HEAD (b)) == NOTE_INSN_DELETED_LABEL)
- {
- rtx bb_note = NEXT_INSN (BB_HEAD (b));
-
- reorder_insns_nobb (label, label, bb_note);
- BB_HEAD (b) = bb_note;
- if (BB_END (b) == bb_note)
- BB_END (b) = label;
- }
+ delete_insn (BB_HEAD (b));
if (dump_file)
fprintf (dump_file, "Deleted label in block %i.\n",
b->index);
}
/* If we fall through an empty block, we can remove it. */
- if (!(mode & CLEANUP_CFGLAYOUT)
+ if (!(mode & (CLEANUP_CFGLAYOUT | CLEANUP_NO_INSN_DEL))
&& single_pred_p (b)
&& (single_pred_edge (b)->flags & EDGE_FALLTHRU)
&& !LABEL_P (BB_HEAD (b))
/* Note that forwarder_block_p true ensures that
there is a successor for this block. */
&& (single_succ_edge (b)->flags & EDGE_FALLTHRU)
- && n_basic_blocks > NUM_FIXED_BLOCKS + 1)
+ && n_basic_blocks_for_fn (cfun) > NUM_FIXED_BLOCKS + 1)
{
if (dump_file)
fprintf (dump_file,
"Deleting fallthru block %i.\n",
b->index);
- c = b->prev_bb == ENTRY_BLOCK_PTR ? b->next_bb : b->prev_bb;
+ c = ((b->prev_bb == ENTRY_BLOCK_PTR_FOR_FN (cfun))
+ ? b->next_bb : b->prev_bb);
redirect_edge_succ_nodup (single_pred_edge (b),
single_succ (b));
delete_basic_block (b);
if (single_succ_p (b)
&& (s = single_succ_edge (b))
&& !(s->flags & EDGE_COMPLEX)
- && (c = s->dest) != EXIT_BLOCK_PTR
+ && (c = s->dest) != EXIT_BLOCK_PTR_FOR_FN (cfun)
&& single_pred_p (c)
&& b != c)
{
can either delete the jump entirely, or replace it
with a simple unconditional jump. */
if (single_succ_p (b)
- && single_succ (b) != EXIT_BLOCK_PTR
+ && single_succ (b) != EXIT_BLOCK_PTR_FOR_FN (cfun)
&& onlyjump_p (BB_END (b))
- && !find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX)
+ && !CROSSING_JUMP_P (BB_END (b))
&& try_redirect_by_replacing_jump (single_succ_edge (b),
single_succ (b),
(mode & CLEANUP_CFGLAYOUT) != 0))
/* Simplify branch to branch. */
if (try_forward_edges (mode, b))
- changed_here = true;
+ {
+ update_forwarder_flag (b);
+ changed_here = true;
+ }
/* Look for shared code between blocks. */
if ((mode & CLEANUP_CROSSJUMP)
&& try_crossjump_bb (mode, b))
changed_here = true;
+ if ((mode & CLEANUP_CROSSJUMP)
+ /* This can lengthen register lifetimes. Do it only after
+ reload. */
+ && reload_completed
+ && try_head_merge_bb (b))
+ changed_here = true;
+
/* Don't get confused by the index shift caused by
deleting blocks. */
if (!changed_here)
}
if ((mode & CLEANUP_CROSSJUMP)
- && try_crossjump_bb (mode, EXIT_BLOCK_PTR))
+ && try_crossjump_bb (mode, EXIT_BLOCK_PTR_FOR_FN (cfun)))
changed = true;
-#ifdef ENABLE_CHECKING
+ if (block_was_dirty)
+ {
+ /* This should only be set by head-merging. */
+ gcc_assert (mode & CLEANUP_CROSSJUMP);
+ df_analyze ();
+ }
+
if (changed)
- verify_flow_info ();
-#endif
+ {
+ /* Edge forwarding in particular can cause hot blocks previously
+ reached by both hot and cold blocks to become dominated only
+ by cold blocks. This will cause the verification below to fail,
+ and lead to now cold code in the hot section. This is not easy
+ to detect and fix during edge forwarding, and in some cases
+ is only visible after newly unreachable blocks are deleted,
+ which will be done in fixup_partitions. */
+ fixup_partitions ();
+ checking_verify_flow_info ();
+ }
changed_overall |= changed;
first_pass = false;
while (changed);
}
- FOR_ALL_BB (b)
+ FOR_ALL_BB_FN (b, cfun)
b->flags &= ~(BB_FORWARDER_BLOCK | BB_NONTHREADABLE_BLOCK);
return changed_overall;
have dominators information, walking blocks backward gets us a
better chance of retaining most debug information than
otherwise. */
- if (MAY_HAVE_DEBUG_STMTS && current_ir_type () == IR_GIMPLE
+ if (MAY_HAVE_DEBUG_INSNS && current_ir_type () == IR_GIMPLE
&& dom_info_available_p (CDI_DOMINATORS))
{
- for (b = EXIT_BLOCK_PTR->prev_bb; b != ENTRY_BLOCK_PTR; b = prev_bb)
+ for (b = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb;
+ b != ENTRY_BLOCK_PTR_FOR_FN (cfun); b = prev_bb)
{
prev_bb = b->prev_bb;
delete_basic_block (b);
else
{
- VEC (basic_block, heap) *h
+ vec<basic_block> h
= get_all_dominated_blocks (CDI_DOMINATORS, b);
- while (VEC_length (basic_block, h))
+ while (h.length ())
{
- b = VEC_pop (basic_block, h);
+ b = h.pop ();
prev_bb = b->prev_bb;
delete_basic_block (b);
}
- VEC_free (basic_block, heap, h);
+ h.release ();
}
changed = true;
}
else
{
- for (b = EXIT_BLOCK_PTR->prev_bb; b != ENTRY_BLOCK_PTR; b = prev_bb)
+ for (b = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb;
+ b != ENTRY_BLOCK_PTR_FOR_FN (cfun); b = prev_bb)
{
prev_bb = b->prev_bb;
/* A dead jump table does not belong to any basic block. Scan insns
between two adjacent basic blocks. */
- FOR_EACH_BB (bb)
+ FOR_EACH_BB_FN (bb, cfun)
{
- rtx insn, next;
+ rtx_insn *insn, *next;
for (insn = NEXT_INSN (BB_END (bb));
insn && !NOTE_INSN_BASIC_BLOCK_P (insn);
&& LABEL_NUSES (insn) == LABEL_PRESERVE_P (insn)
&& JUMP_TABLE_DATA_P (next))
{
- rtx label = insn, jump = next;
+ rtx_insn *label = insn, *jump = next;
if (dump_file)
fprintf (dump_file, "Dead jumptable %i removed\n",
if ((mode & CLEANUP_EXPENSIVE) && !reload_completed
&& !delete_trivially_dead_insns (get_insns (), max_reg_num ()))
break;
- else if ((mode & CLEANUP_CROSSJUMP)
- && crossjumps_occured)
+ if ((mode & CLEANUP_CROSSJUMP) && crossjumps_occured)
run_fast_dce ();
}
else
if (!(mode & CLEANUP_CFGLAYOUT))
delete_dead_jumptables ();
+ /* ??? We probably do this way too often. */
+ if (current_loops
+ && (changed
+ || (mode & CLEANUP_CFG_CHANGED)))
+ {
+ timevar_push (TV_REPAIR_LOOPS);
+ /* The above doesn't preserve dominance info if available. */
+ gcc_assert (!dom_info_available_p (CDI_DOMINATORS));
+ calculate_dominance_info (CDI_DOMINATORS);
+ fix_loop_structure (NULL);
+ free_dominance_info (CDI_DOMINATORS);
+ timevar_pop (TV_REPAIR_LOOPS);
+ }
+
timevar_pop (TV_CLEANUP_CFG);
return changed;
}
\f
-static unsigned int
-rest_of_handle_jump (void)
-{
- if (crtl->tail_call_emit)
- fixup_tail_calls ();
- return 0;
-}
+namespace {
-struct rtl_opt_pass pass_jump =
+const pass_data pass_data_jump =
{
- {
- RTL_PASS,
- "sibling", /* name */
- NULL, /* gate */
- rest_of_handle_jump, /* execute */
- NULL, /* sub */
- NULL, /* next */
- 0, /* static_pass_number */
- TV_JUMP, /* tv_id */
- 0, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- TODO_ggc_collect, /* todo_flags_start */
- TODO_verify_flow, /* todo_flags_finish */
- }
+ RTL_PASS, /* type */
+ "jump", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ TV_JUMP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0, /* todo_flags_finish */
};
+class pass_jump : public rtl_opt_pass
+{
+public:
+ pass_jump (gcc::context *ctxt)
+ : rtl_opt_pass (pass_data_jump, ctxt)
+ {}
+
+ /* opt_pass methods: */
+ virtual unsigned int execute (function *);
+
+}; // class pass_jump
-static unsigned int
-rest_of_handle_jump2 (void)
+unsigned int
+pass_jump::execute (function *)
{
delete_trivially_dead_insns (get_insns (), max_reg_num ());
if (dump_file)
return 0;
}
+} // anon namespace
+
+rtl_opt_pass *
+make_pass_jump (gcc::context *ctxt)
+{
+ return new pass_jump (ctxt);
+}
+\f
+namespace {
-struct rtl_opt_pass pass_jump2 =
+const pass_data pass_data_jump2 =
{
- {
- RTL_PASS,
- "jump", /* name */
- NULL, /* gate */
- rest_of_handle_jump2, /* execute */
- NULL, /* sub */
- NULL, /* next */
- 0, /* static_pass_number */
- TV_JUMP, /* tv_id */
- 0, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- TODO_ggc_collect, /* todo_flags_start */
- TODO_dump_func | TODO_verify_rtl_sharing,/* todo_flags_finish */
- }
+ RTL_PASS, /* type */
+ "jump2", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ TV_JUMP, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0, /* todo_flags_finish */
};
+class pass_jump2 : public rtl_opt_pass
+{
+public:
+ pass_jump2 (gcc::context *ctxt)
+ : rtl_opt_pass (pass_data_jump2, ctxt)
+ {}
+
+ /* opt_pass methods: */
+ virtual unsigned int execute (function *)
+ {
+ cleanup_cfg (flag_crossjumping ? CLEANUP_CROSSJUMP : 0);
+ return 0;
+ }
+}; // class pass_jump2
+
+} // anon namespace
+
+rtl_opt_pass *
+make_pass_jump2 (gcc::context *ctxt)
+{
+ return new pass_jump2 (ctxt);
+}
projects / gcc.git / blobdiff