/* Allocate registers for pseudo-registers that span basic blocks.
Copyright (C) 1987, 1988, 1991, 1994, 1996, 1997, 1998,
- 1999, 2000, 2002 Free Software Foundation, Inc.
+ 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007
+ Free Software Foundation, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
-Software Foundation; either version 2, or (at your option) any later
+Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
-
#include "machmode.h"
#include "hard-reg-set.h"
#include "rtl.h"
#include "tm_p.h"
#include "flags.h"
-#include "basic-block.h"
#include "regs.h"
#include "function.h"
#include "insn-config.h"
+#include "recog.h"
#include "reload.h"
#include "output.h"
#include "toplev.h"
+#include "tree-pass.h"
+#include "timevar.h"
+#include "df.h"
+#include "vecprim.h"
+#include "dbgcnt.h"
+#include "ra.h"
/* This pass of the compiler performs global register allocation.
It assigns hard register numbers to all the pseudo registers
reg numbers to allocnos and vice versa.
max_allocno gets the number of allocnos in use.
- 2. Allocate a max_allocno by max_allocno conflict bit matrix and clear it.
- Allocate a max_allocno by FIRST_PSEUDO_REGISTER conflict matrix
- for conflicts between allocnos and explicit hard register use
- (which includes use of pseudo-registers allocated by local_alloc).
-
- 3. For each basic block
- walk forward through the block, recording which
- pseudo-registers and which hardware registers are live.
- Build the conflict matrix between the pseudo-registers
- and another of pseudo-registers versus hardware registers.
- Also record the preferred hardware registers
- for each pseudo-register.
-
- 4. Sort a table of the allocnos into order of
- desirability of the variables.
-
- 5. Allocate the variables in that order; each if possible into
- a preferred register, else into another register. */
-\f
-/* Number of pseudo-registers which are candidates for allocation. */
-
-static int max_allocno;
-
-/* Indexed by (pseudo) reg number, gives the allocno, or -1
- for pseudo registers which are not to be allocated. */
-
-static int *reg_allocno;
-
-struct allocno
-{
- int reg;
- /* Gives the number of consecutive hard registers needed by that
- pseudo reg. */
- int size;
-
- /* Number of calls crossed by each allocno. */
- int calls_crossed;
-
- /* Number of refs to each allocno. */
- int n_refs;
-
- /* Frequency of uses of each allocno. */
- int freq;
-
- /* Guess at live length of each allocno.
- This is actually the max of the live lengths of the regs. */
- int live_length;
-
- /* Set of hard regs conflicting with allocno N. */
+ 2. Allocate a max_allocno by max_allocno compressed triangular conflict
+ bit matrix (a triangular bit matrix with portions removed for which we
+ can guarantee there are no conflicts, example: two local pseudos that
+ live in different basic blocks) and clear it. This is called "conflict".
+ Note that for triangular bit matrices, there are two possible equations
+ for computing the bit number for two allocnos: LOW and HIGH (LOW < HIGH):
- HARD_REG_SET hard_reg_conflicts;
+ 1) BITNUM = f(HIGH) + LOW, where
+ f(HIGH) = (HIGH * (HIGH - 1)) / 2
- /* Set of hard regs preferred by allocno N.
- This is used to make allocnos go into regs that are copied to or from them,
- when possible, to reduce register shuffling. */
+ 2) BITNUM = f(LOW) + HIGH, where
+ f(LOW) = LOW * (max_allocno - LOW) + (LOW * (LOW - 1)) / 2 - LOW - 1
- HARD_REG_SET hard_reg_preferences;
+ We use the second (and less common) equation as this gives us better
+ cache locality for local allocnos that are live within the same basic
+ block. Also note that f(HIGH) and f(LOW) can be precalculated for all
+ values of HIGH and LOW, so all that is necessary to compute the bit
+ number for two allocnos LOW and HIGH is a load followed by an addition.
- /* Similar, but just counts register preferences made in simple copy
- operations, rather than arithmetic. These are given priority because
- we can always eliminate an insn by using these, but using a register
- in the above list won't always eliminate an insn. */
+ Allocate a max_allocno by FIRST_PSEUDO_REGISTER conflict matrix for
+ conflicts between allocnos and explicit hard register use (which
+ includes use of pseudo-registers allocated by local_alloc). This
+ is the hard_reg_conflicts inside each allocno.
- HARD_REG_SET hard_reg_copy_preferences;
+ 3. For each basic block, walk backward through the block, recording
+ which pseudo-registers and which hardware registers are live.
+ Build the conflict matrix between the pseudo-registers and another of
+ pseudo-registers versus hardware registers.
- /* Similar to hard_reg_preferences, but includes bits for subsequent
- registers when an allocno is multi-word. The above variable is used for
- allocation while this is used to build reg_someone_prefers, below. */
+ 4. For each basic block, walk backward through the block, recording
+ the preferred hardware registers for each pseudo-register.
- HARD_REG_SET hard_reg_full_preferences;
-
- /* Set of hard registers that some later allocno has a preference for. */
-
- HARD_REG_SET regs_someone_prefers;
-
-#ifdef STACK_REGS
- /* Set to true if allocno can't be allocated in the stack register. */
- bool no_stack_reg;
-#endif
-};
-
-static struct allocno *allocno;
+ 5. Sort a table of the allocnos into order of desirability of the variables.
+ 6. Allocate the variables in that order; each if possible into
+ a preferred register, else into another register. */
+\f
/* A vector of the integers from 0 to max_allocno-1,
sorted in the order of first-to-be-allocated first. */
static int *allocno_order;
-/* Indexed by (pseudo) reg number, gives the number of another
- lower-numbered pseudo reg which can share a hard reg with this pseudo
- *even if the two pseudos would otherwise appear to conflict*. */
-
-static int *reg_may_share;
-
-/* Define the number of bits in each element of `conflicts' and what
- type that element has. We use the largest integer format on the
- host machine. */
-
-#define INT_BITS HOST_BITS_PER_WIDE_INT
-#define INT_TYPE HOST_WIDE_INT
-
-/* max_allocno by max_allocno array of bits,
- recording whether two allocno's conflict (can't go in the same
- hardware register).
-
- `conflicts' is symmetric after the call to mirror_conflicts. */
-
-static INT_TYPE *conflicts;
-
-/* Number of ints require to hold max_allocno bits.
- This is the length of a row in `conflicts'. */
-
-static int allocno_row_words;
-
-/* Two macros to test or store 1 in an element of `conflicts'. */
-
-#define CONFLICTP(I, J) \
- (conflicts[(I) * allocno_row_words + (unsigned) (J) / INT_BITS] \
- & ((INT_TYPE) 1 << ((unsigned) (J) % INT_BITS)))
-
-/* For any allocno set in ALLOCNO_SET, set ALLOCNO to that allocno,
- and execute CODE. */
-#define EXECUTE_IF_SET_IN_ALLOCNO_SET(ALLOCNO_SET, ALLOCNO, CODE) \
-do { \
- int i_; \
- int allocno_; \
- INT_TYPE *p_ = (ALLOCNO_SET); \
- \
- for (i_ = allocno_row_words - 1, allocno_ = 0; i_ >= 0; \
- i_--, allocno_ += INT_BITS) \
- { \
- unsigned INT_TYPE word_ = (unsigned INT_TYPE) *p_++; \
- \
- for ((ALLOCNO) = allocno_; word_; word_ >>= 1, (ALLOCNO)++) \
- { \
- if (word_ & 1) \
- {CODE;} \
- } \
- } \
-} while (0)
-
-/* This doesn't work for non-GNU C due to the way CODE is macro expanded. */
-#if 0
-/* For any allocno that conflicts with IN_ALLOCNO, set OUT_ALLOCNO to
- the conflicting allocno, and execute CODE. This macro assumes that
- mirror_conflicts has been run. */
-#define EXECUTE_IF_CONFLICT(IN_ALLOCNO, OUT_ALLOCNO, CODE)\
- EXECUTE_IF_SET_IN_ALLOCNO_SET (conflicts + (IN_ALLOCNO) * allocno_row_words,\
- OUT_ALLOCNO, (CODE))
-#endif
-
-/* Set of hard regs currently live (during scan of all insns). */
-
-static HARD_REG_SET hard_regs_live;
-
/* Set of registers that global-alloc isn't supposed to use. */
static HARD_REG_SET no_global_alloc_regs;
#define SET_REGBIT(TABLE, I, J) SET_HARD_REG_BIT (allocno[I].TABLE, J)
-/* Bit mask for allocnos live at current point in the scan. */
-
-static INT_TYPE *allocnos_live;
-
-/* Test, set or clear bit number I in allocnos_live,
- a bit vector indexed by allocno. */
-
-#define SET_ALLOCNO_LIVE(I) \
- (allocnos_live[(unsigned) (I) / INT_BITS] \
- |= ((INT_TYPE) 1 << ((unsigned) (I) % INT_BITS)))
-
-#define CLEAR_ALLOCNO_LIVE(I) \
- (allocnos_live[(unsigned) (I) / INT_BITS] \
- &= ~((INT_TYPE) 1 << ((unsigned) (I) % INT_BITS)))
-
/* This is turned off because it doesn't work right for DImode.
(And it is only used for DImode, so the other cases are worthless.)
The problem is that it isn't true that there is NO possibility of conflict;
no_conflict_pairs[NUM_NO_CONFLICT_PAIRS];
#endif /* 0 */
-/* Record all regs that are set in any one insn.
- Communication from mark_reg_{store,clobber} and global_conflicts. */
+/* Return true if *LOC contains an asm. */
+
+static int
+insn_contains_asm_1 (rtx *loc, void *data ATTRIBUTE_UNUSED)
+{
+ if ( !*loc)
+ return 0;
+ if (GET_CODE (*loc) == ASM_OPERANDS)
+ return 1;
+ return 0;
+}
+
+
+/* Return true if INSN contains an ASM. */
+
+static int
+insn_contains_asm (rtx insn)
+{
+ return for_each_rtx (&insn, insn_contains_asm_1, NULL);
+}
+
+
+static void
+compute_regs_asm_clobbered (char *regs_asm_clobbered)
+{
+ basic_block bb;
+
+ memset (regs_asm_clobbered, 0, sizeof (char) * FIRST_PSEUDO_REGISTER);
+
+ FOR_EACH_BB (bb)
+ {
+ rtx insn;
+ FOR_BB_INSNS_REVERSE (bb, insn)
+ {
+ struct df_ref **def_rec;
+ if (insn_contains_asm (insn))
+ for (def_rec = DF_INSN_DEFS (insn); *def_rec; def_rec++)
+ {
+ struct df_ref *def = *def_rec;
+ unsigned int dregno = DF_REF_REGNO (def);
+ if (dregno < FIRST_PSEUDO_REGISTER)
+ {
+ unsigned int i;
+ enum machine_mode mode = GET_MODE (DF_REF_REAL_REG (def));
+ unsigned int end = dregno
+ + hard_regno_nregs[dregno][mode] - 1;
+ for (i = dregno; i <= end; ++i)
+ regs_asm_clobbered[i] = 1;
+ }
+ }
+ }
+ }
+}
-static rtx *regs_set;
-static int n_regs_set;
/* All registers that can be eliminated. */
static HARD_REG_SET eliminable_regset;
-static int allocno_compare PARAMS ((const PTR, const PTR));
-static void global_conflicts PARAMS ((void));
-static void mirror_conflicts PARAMS ((void));
-static void expand_preferences PARAMS ((void));
-static void prune_preferences PARAMS ((void));
-static void find_reg PARAMS ((int, HARD_REG_SET, int, int, int));
-static void record_one_conflict PARAMS ((int));
-static void record_conflicts PARAMS ((int *, int));
-static void mark_reg_store PARAMS ((rtx, rtx, void *));
-static void mark_reg_clobber PARAMS ((rtx, rtx, void *));
-static void mark_reg_conflicts PARAMS ((rtx));
-static void mark_reg_death PARAMS ((rtx));
-static void mark_reg_live_nc PARAMS ((int, enum machine_mode));
-static void set_preference PARAMS ((rtx, rtx));
-static void dump_conflicts PARAMS ((FILE *));
-static void reg_becomes_live PARAMS ((rtx, rtx, void *));
-static void reg_dies PARAMS ((int, enum machine_mode,
- struct insn_chain *));
+static int regno_compare (const void *, const void *);
+static int allocno_compare (const void *, const void *);
+static void expand_preferences (void);
+static void prune_preferences (void);
+static void set_preferences (void);
+static void find_reg (int, HARD_REG_SET, int, int, int);
+static void dump_conflicts (FILE *);
+static void build_insn_chain (void);
\f
-/* Perform allocation of pseudo-registers not allocated by local_alloc.
- FILE is a file to output debugging information on,
- or zero if such output is not desired.
- Return value is nonzero if reload failed
- and we must not do any more for this function. */
+/* Look through the list of eliminable registers. Set ELIM_SET to the
+ set of registers which may be eliminated. Set NO_GLOBAL_SET to the
+ set of registers which may not be used across blocks.
-int
-global_alloc (file)
- FILE *file;
+ This will normally be called with ELIM_SET as the file static
+ variable eliminable_regset, and NO_GLOBAL_SET as the file static
+ variable NO_GLOBAL_ALLOC_REGS. */
+
+static void
+compute_regsets (HARD_REG_SET *elim_set,
+ HARD_REG_SET *no_global_set)
{
- int retval;
+
+/* Like regs_ever_live, but 1 if a reg is set or clobbered from an asm.
+ Unlike regs_ever_live, elements of this array corresponding to
+ eliminable regs like the frame pointer are set if an asm sets them. */
+ char *regs_asm_clobbered = alloca (FIRST_PSEUDO_REGISTER * sizeof (char));
+
#ifdef ELIMINABLE_REGS
static const struct {const int from, to; } eliminables[] = ELIMINABLE_REGS;
+ size_t i;
#endif
int need_fp
= (! flag_omit_frame_pointer
-#ifdef EXIT_IGNORE_STACK
|| (current_function_calls_alloca && EXIT_IGNORE_STACK)
-#endif
|| FRAME_POINTER_REQUIRED);
- size_t i;
- rtx x;
+ max_regno = max_reg_num ();
+ compact_blocks ();
max_allocno = 0;
/* A machine may have certain hard registers that
are safe to use only within a basic block. */
- CLEAR_HARD_REG_SET (no_global_alloc_regs);
+ CLEAR_HARD_REG_SET (*no_global_set);
+ CLEAR_HARD_REG_SET (*elim_set);
+ compute_regs_asm_clobbered (regs_asm_clobbered);
/* Build the regset of all eliminable registers and show we can't use those
that we already know won't be eliminated. */
#ifdef ELIMINABLE_REGS
for (i = 0; i < ARRAY_SIZE (eliminables); i++)
{
- SET_HARD_REG_BIT (eliminable_regset, eliminables[i].from);
+ bool cannot_elim
+ = (! CAN_ELIMINATE (eliminables[i].from, eliminables[i].to)
+ || (eliminables[i].to == STACK_POINTER_REGNUM && need_fp));
- if (! CAN_ELIMINATE (eliminables[i].from, eliminables[i].to)
- || (eliminables[i].to == STACK_POINTER_REGNUM && need_fp))
- SET_HARD_REG_BIT (no_global_alloc_regs, eliminables[i].from);
+ if (!regs_asm_clobbered[eliminables[i].from])
+ {
+ SET_HARD_REG_BIT (*elim_set, eliminables[i].from);
+
+ if (cannot_elim)
+ SET_HARD_REG_BIT (*no_global_set, eliminables[i].from);
+ }
+ else if (cannot_elim)
+ error ("%s cannot be used in asm here",
+ reg_names[eliminables[i].from]);
+ else
+ df_set_regs_ever_live (eliminables[i].from, true);
}
#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
- SET_HARD_REG_BIT (eliminable_regset, HARD_FRAME_POINTER_REGNUM);
- if (need_fp)
- SET_HARD_REG_BIT (no_global_alloc_regs, HARD_FRAME_POINTER_REGNUM);
+ if (!regs_asm_clobbered[HARD_FRAME_POINTER_REGNUM])
+ {
+ SET_HARD_REG_BIT (*elim_set, HARD_FRAME_POINTER_REGNUM);
+ if (need_fp)
+ SET_HARD_REG_BIT (*no_global_set, HARD_FRAME_POINTER_REGNUM);
+ }
+ else if (need_fp)
+ error ("%s cannot be used in asm here",
+ reg_names[HARD_FRAME_POINTER_REGNUM]);
+ else
+ df_set_regs_ever_live (HARD_FRAME_POINTER_REGNUM, true);
#endif
#else
- SET_HARD_REG_BIT (eliminable_regset, FRAME_POINTER_REGNUM);
- if (need_fp)
- SET_HARD_REG_BIT (no_global_alloc_regs, FRAME_POINTER_REGNUM);
+ if (!regs_asm_clobbered[FRAME_POINTER_REGNUM])
+ {
+ SET_HARD_REG_BIT (*elim_set, FRAME_POINTER_REGNUM);
+ if (need_fp)
+ SET_HARD_REG_BIT (*no_global_set, FRAME_POINTER_REGNUM);
+ }
+ else if (need_fp)
+ error ("%s cannot be used in asm here", reg_names[FRAME_POINTER_REGNUM]);
+ else
+ df_set_regs_ever_live (FRAME_POINTER_REGNUM, true);
#endif
+}
+
+/* Perform allocation of pseudo-registers not allocated by local_alloc.
+
+ Return value is nonzero if reload failed
+ and we must not do any more for this function. */
+
+static int
+global_alloc (void)
+{
+ int retval;
+ size_t i;
+ int max_blk;
+ int *num_allocnos_per_blk;
+
+ compute_regsets (&eliminable_regset, &no_global_alloc_regs);
/* Track which registers have already been used. Start with registers
explicitly in the rtl, then registers allocated by local register
else
cheap_regs = call_used_regs;
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (regs_ever_live[i] || cheap_regs[i])
+ if (df_regs_ever_live_p (i) || cheap_regs[i])
SET_HARD_REG_BIT (regs_used_so_far, i);
}
#else
/* We consider registers that do not have to be saved over calls as if
they were already used since there is no cost in using them. */
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (regs_ever_live[i] || call_used_regs[i])
+ if (df_regs_ever_live_p (i) || call_used_regs[i])
SET_HARD_REG_BIT (regs_used_so_far, i);
#endif
/* Establish mappings from register number to allocation number
and vice versa. In the process, count the allocnos. */
- reg_allocno = (int *) xmalloc (max_regno * sizeof (int));
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- reg_allocno[i] = -1;
-
- /* Initialize the shared-hard-reg mapping
- from the list of pairs that may share. */
- reg_may_share = (int *) xcalloc (max_regno, sizeof (int));
- for (x = regs_may_share; x; x = XEXP (XEXP (x, 1), 1))
- {
- int r1 = REGNO (XEXP (x, 0));
- int r2 = REGNO (XEXP (XEXP (x, 1), 0));
- if (r1 > r2)
- reg_may_share[r1] = r2;
- else
- reg_may_share[r2] = r1;
- }
+ reg_allocno = XNEWVEC (int, max_regno);
+ /* Initially fill the reg_allocno array with regno's... */
+ max_blk = 0;
+ max_allocno = 0;
for (i = FIRST_PSEUDO_REGISTER; i < (size_t) max_regno; i++)
/* Note that reg_live_length[i] < 0 indicates a "constant" reg
that we are supposed to refrain from putting in a hard reg.
&& (! current_function_has_nonlocal_label
|| REG_N_CALLS_CROSSED (i) == 0))
{
- if (reg_renumber[i] < 0 && reg_may_share[i] && reg_allocno[reg_may_share[i]] >= 0)
- reg_allocno[i] = reg_allocno[reg_may_share[i]];
- else
- reg_allocno[i] = max_allocno++;
- if (REG_LIVE_LENGTH (i) == 0)
- abort ();
+ int blk = regno_basic_block (i);
+ reg_allocno[max_allocno++] = i;
+ if (blk > max_blk)
+ max_blk = blk;
+ gcc_assert (REG_LIVE_LENGTH (i));
}
- else
- reg_allocno[i] = -1;
- allocno = (struct allocno *) xcalloc (max_allocno, sizeof (struct allocno));
+ allocno = XCNEWVEC (struct allocno, max_allocno);
+ partial_bitnum = XNEWVEC (HOST_WIDE_INT, max_allocno);
+ num_allocnos_per_blk = XCNEWVEC (int, max_blk + 1);
- for (i = FIRST_PSEUDO_REGISTER; i < (size_t) max_regno; i++)
- if (reg_allocno[i] >= 0)
- {
- int num = reg_allocno[i];
- allocno[num].reg = i;
- allocno[num].size = PSEUDO_REGNO_SIZE (i);
- allocno[num].calls_crossed += REG_N_CALLS_CROSSED (i);
- allocno[num].n_refs += REG_N_REFS (i);
- allocno[num].freq += REG_FREQ (i);
- if (allocno[num].live_length < REG_LIVE_LENGTH (i))
- allocno[num].live_length = REG_LIVE_LENGTH (i);
- }
+ /* ...so we can sort them in the order we want them to receive
+ their allocnos. */
+ qsort (reg_allocno, max_allocno, sizeof (int), regno_compare);
+
+ for (i = 0; i < (size_t) max_allocno; i++)
+ {
+ int regno = reg_allocno[i];
+ int blk = regno_basic_block (regno);
+ num_allocnos_per_blk[blk]++;
+ allocno[i].reg = regno;
+ allocno[i].size = PSEUDO_REGNO_SIZE (regno);
+ allocno[i].calls_crossed += REG_N_CALLS_CROSSED (regno);
+ allocno[i].freq_calls_crossed += REG_FREQ_CALLS_CROSSED (regno);
+ allocno[i].throwing_calls_crossed
+ += REG_N_THROWING_CALLS_CROSSED (regno);
+ allocno[i].n_refs += REG_N_REFS (regno);
+ allocno[i].freq += REG_FREQ (regno);
+ if (allocno[i].live_length < REG_LIVE_LENGTH (regno))
+ allocno[i].live_length = REG_LIVE_LENGTH (regno);
+ }
+
+ /* The "global" block must contain all allocnos. */
+ num_allocnos_per_blk[0] = max_allocno;
+
+ /* Now reinitialize the reg_allocno array in terms of the
+ optimized regno to allocno mapping we created above. */
+ for (i = 0; i < (size_t) max_regno; i++)
+ reg_allocno[i] = -1;
+
+ max_bitnum = 0;
+ for (i = 0; i < (size_t) max_allocno; i++)
+ {
+ int regno = allocno[i].reg;
+ int blk = regno_basic_block (regno);
+ int row_size = --num_allocnos_per_blk[blk];
+ reg_allocno[regno] = (int) i;
+ partial_bitnum[i] = (row_size > 0) ? max_bitnum - ((int) i + 1) : -1;
+ max_bitnum += row_size;
+ }
+
+#ifdef ENABLE_CHECKING
+ gcc_assert (max_bitnum <=
+ (((HOST_WIDE_INT) max_allocno *
+ ((HOST_WIDE_INT) max_allocno - 1)) / 2));
+#endif
+
+ if (dump_file)
+ {
+ HOST_WIDE_INT num_bits, num_bytes, actual_bytes;
+
+ fprintf (dump_file, "## max_blk: %d\n", max_blk);
+ fprintf (dump_file, "## max_regno: %d\n", max_regno);
+ fprintf (dump_file, "## max_allocno: %d\n", max_allocno);
+
+ num_bits = max_bitnum;
+ num_bytes = CEIL (num_bits, 8);
+ actual_bytes = num_bytes;
+ fprintf (dump_file, "## Compressed triangular bitmatrix size: ");
+ fprintf (dump_file, HOST_WIDE_INT_PRINT_DEC " bits, ", num_bits);
+ fprintf (dump_file, HOST_WIDE_INT_PRINT_DEC " bytes\n", num_bytes);
+
+ num_bits = ((HOST_WIDE_INT) max_allocno *
+ ((HOST_WIDE_INT) max_allocno - 1)) / 2;
+ num_bytes = CEIL (num_bits, 8);
+ fprintf (dump_file, "## Standard triangular bitmatrix size: ");
+ fprintf (dump_file, HOST_WIDE_INT_PRINT_DEC " bits, ", num_bits);
+ fprintf (dump_file, HOST_WIDE_INT_PRINT_DEC " bytes [%.2f%%]\n",
+ num_bytes, 100.0 * ((double) actual_bytes / (double) num_bytes));
+
+ num_bits = (HOST_WIDE_INT) max_allocno * (HOST_WIDE_INT) max_allocno;
+ num_bytes = CEIL (num_bits, 8);
+ fprintf (dump_file, "## Square bitmatrix size: ");
+ fprintf (dump_file, HOST_WIDE_INT_PRINT_DEC " bits, ", num_bits);
+ fprintf (dump_file, HOST_WIDE_INT_PRINT_DEC " bytes [%.2f%%]\n",
+ num_bytes, 100.0 * ((double) actual_bytes / (double) num_bytes));
+ }
/* Calculate amount of usage of each hard reg by pseudos
allocated by local-alloc. This is to see if we want to
override it. */
- memset ((char *) local_reg_live_length, 0, sizeof local_reg_live_length);
- memset ((char *) local_reg_n_refs, 0, sizeof local_reg_n_refs);
- memset ((char *) local_reg_freq, 0, sizeof local_reg_freq);
+ memset (local_reg_live_length, 0, sizeof local_reg_live_length);
+ memset (local_reg_n_refs, 0, sizeof local_reg_n_refs);
+ memset (local_reg_freq, 0, sizeof local_reg_freq);
for (i = FIRST_PSEUDO_REGISTER; i < (size_t) max_regno; i++)
if (reg_renumber[i] >= 0)
{
int regno = reg_renumber[i];
- int endregno = regno + HARD_REGNO_NREGS (regno, PSEUDO_REGNO_MODE (i));
+ int endregno = end_hard_regno (PSEUDO_REGNO_MODE (i), regno);
int j;
for (j = regno; j < endregno; j++)
/* We can't override local-alloc for a reg used not just by local-alloc. */
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (regs_ever_live[i])
+ if (df_regs_ever_live_p (i))
local_reg_n_refs[i] = 0, local_reg_freq[i] = 0;
- allocno_row_words = (max_allocno + INT_BITS - 1) / INT_BITS;
-
- /* We used to use alloca here, but the size of what it would try to
- allocate would occasionally cause it to exceed the stack limit and
- cause unpredictable core dumps. Some examples were > 2Mb in size. */
- conflicts = (INT_TYPE *) xcalloc (max_allocno * allocno_row_words,
- sizeof (INT_TYPE));
+ if (dump_file)
+ {
+ for (i = FIRST_PSEUDO_REGISTER; i < (size_t) max_regno; i++)
+ {
+ fprintf (dump_file, "%d REG_N_REFS=%d, REG_FREQ=%d, REG_LIVE_LENGTH=%d\n",
+ (int)i, REG_N_REFS (i), REG_FREQ (i), REG_LIVE_LENGTH (i));
+ }
+ fprintf (dump_file, "regs_ever_live =");
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (df_regs_ever_live_p (i))
+ fprintf (dump_file, " %d", (int)i);
+ fprintf (dump_file, "\n");
+ }
- allocnos_live = (INT_TYPE *) xmalloc (allocno_row_words * sizeof (INT_TYPE));
+ conflicts = NULL;
+ adjacency = NULL;
+ adjacency_pool = NULL;
/* If there is work to be done (at least one reg to allocate),
perform global conflict analysis and allocate the regs. */
if (max_allocno > 0)
{
+ /* We used to use alloca here, but the size of what it would try to
+ allocate would occasionally cause it to exceed the stack limit and
+ cause unpredictable core dumps. Some examples were > 2Mb in size. */
+ conflicts = XCNEWVEC (HOST_WIDEST_FAST_INT,
+ CEIL(max_bitnum, HOST_BITS_PER_WIDEST_FAST_INT));
+
+ adjacency = XCNEWVEC (adjacency_t *, max_allocno);
+ adjacency_pool = create_alloc_pool ("global_alloc adjacency list pool",
+ sizeof (adjacency_t), 1024);
+
/* Scan all the insns and compute the conflicts among allocnos
and between allocnos and hard regs. */
global_conflicts ();
- mirror_conflicts ();
+ /* There is just too much going on in the register allocators to
+ keep things up to date. At the end we have to rescan anyway
+ because things change when the reload_completed flag is set.
+ So we just turn off scanning and we will rescan by hand.
+
+ However, we needed to do the rescanning before this point to
+ get the new insns scanned inserted by local_alloc scanned for
+ global_conflicts. */
+ df_set_flags (DF_NO_INSN_RESCAN);
/* Eliminate conflicts between pseudos and eliminable registers. If
the register is not eliminated, the pseudo won't really be able to
So in either case, we can ignore the conflict. Likewise for
preferences. */
+ set_preferences ();
+
for (i = 0; i < (size_t) max_allocno; i++)
{
AND_COMPL_HARD_REG_SET (allocno[i].hard_reg_conflicts,
/* Determine the order to allocate the remaining pseudo registers. */
- allocno_order = (int *) xmalloc (max_allocno * sizeof (int));
+ allocno_order = XNEWVEC (int, max_allocno);
for (i = 0; i < (size_t) max_allocno; i++)
allocno_order[i] = i;
prune_preferences ();
- if (file)
- dump_conflicts (file);
+ if (dump_file)
+ dump_conflicts (dump_file);
/* Try allocating them, one by one, in that order,
except for parameters marked with reg_live_length[regno] == -2. */
if (reg_renumber[allocno[allocno_order[i]].reg] < 0
&& REG_LIVE_LENGTH (allocno[allocno_order[i]].reg) >= 0)
{
+ if (!dbg_cnt (global_alloc_at_reg))
+ break;
/* If we have more than one register class,
first try allocating in the class that is cheapest
for this pseudo-reg. If that fails, try any reg. */
}
free (allocno_order);
+ free (conflicts);
}
- /* Do the reloads now while the allocno data still exist, so that we can
+ /* Do the reloads now while the allocno data still exists, so that we can
try to assign new hard regs to any pseudo regs that are spilled. */
#if 0 /* We need to eliminate regs even if there is no rtl code,
for the sake of debugging information. */
- if (n_basic_blocks > 0)
+ if (n_basic_blocks > NUM_FIXED_BLOCKS)
#endif
{
- build_insn_chain (get_insns ());
+ build_insn_chain ();
retval = reload (get_insns (), 1);
}
/* Clean up. */
free (reg_allocno);
- free (reg_may_share);
+ free (num_allocnos_per_blk);
+ free (partial_bitnum);
free (allocno);
- free (conflicts);
- free (allocnos_live);
+ if (adjacency != NULL)
+ {
+ free_alloc_pool (adjacency_pool);
+ free (adjacency);
+ }
return retval;
}
+/* Sort predicate for ordering the regnos. We want the regno to allocno
+ mapping to have the property that all "global" regnos (ie, regnos that
+ are referenced in more than one basic block) have smaller allocno values
+ than "local" regnos (ie, regnos referenced in only one basic block).
+ In addition, for two basic blocks "i" and "j" with i < j, all regnos
+ local to basic block i should have smaller allocno values than regnos
+ local to basic block j.
+ Returns -1 (1) if *v1p should be allocated before (after) *v2p. */
+
+static int
+regno_compare (const void *v1p, const void *v2p)
+{
+ int regno1 = *(const int *)v1p;
+ int regno2 = *(const int *)v2p;
+ int blk1 = REG_BASIC_BLOCK (regno1);
+ int blk2 = REG_BASIC_BLOCK (regno2);
+
+ /* Prefer lower numbered basic blocks. Note that global and unknown
+ blocks have negative values, giving them high precedence. */
+ if (blk1 - blk2)
+ return blk1 - blk2;
+
+ /* If both regs are referenced from the same block, sort by regno. */
+ return regno1 - regno2;
+}
+
/* Sort predicate for ordering the allocnos.
Returns -1 (1) if *v1 should be allocated before (after) *v2. */
static int
-allocno_compare (v1p, v2p)
- const PTR v1p;
- const PTR v2p;
+allocno_compare (const void *v1p, const void *v2p)
{
int v1 = *(const int *)v1p, v2 = *(const int *)v2p;
/* Note that the quotient will never be bigger than
return v1 - v2;
}
\f
-/* Scan the rtl code and record all conflicts and register preferences in the
- conflict matrices and preference tables. */
-
-static void
-global_conflicts ()
-{
- int i;
- basic_block b;
- rtx insn;
- int *block_start_allocnos;
-
- /* Make a vector that mark_reg_{store,clobber} will store in. */
- regs_set = (rtx *) xmalloc (max_parallel * sizeof (rtx) * 2);
-
- block_start_allocnos = (int *) xmalloc (max_allocno * sizeof (int));
-
- FOR_EACH_BB (b)
- {
- memset ((char *) allocnos_live, 0, allocno_row_words * sizeof (INT_TYPE));
-
- /* Initialize table of registers currently live
- to the state at the beginning of this basic block.
- This also marks the conflicts among hard registers
- and any allocnos that are live.
-
- For pseudo-regs, there is only one bit for each one
- no matter how many hard regs it occupies.
- This is ok; we know the size from PSEUDO_REGNO_SIZE.
- For explicit hard regs, we cannot know the size that way
- since one hard reg can be used with various sizes.
- Therefore, we must require that all the hard regs
- implicitly live as part of a multi-word hard reg
- are explicitly marked in basic_block_live_at_start. */
-
- {
- regset old = b->global_live_at_start;
- int ax = 0;
-
- REG_SET_TO_HARD_REG_SET (hard_regs_live, old);
- EXECUTE_IF_SET_IN_REG_SET (old, FIRST_PSEUDO_REGISTER, i,
- {
- int a = reg_allocno[i];
- if (a >= 0)
- {
- SET_ALLOCNO_LIVE (a);
- block_start_allocnos[ax++] = a;
- }
- else if ((a = reg_renumber[i]) >= 0)
- mark_reg_live_nc
- (a, PSEUDO_REGNO_MODE (i));
- });
-
- /* Record that each allocno now live conflicts with each hard reg
- now live.
-
- It is not necessary to mark any conflicts between pseudos as
- this point, even for pseudos which are live at the start of
- the basic block.
-
- Given two pseudos X and Y and any point in the CFG P.
-
- On any path to point P where X and Y are live one of the
- following conditions must be true:
-
- 1. X is live at some instruction on the path that
- evaluates Y.
-
- 2. Y is live at some instruction on the path that
- evaluates X.
-
- 3. Either X or Y is not evaluted on the path to P
- (ie it is used uninitialized) and thus the
- conflict can be ignored.
-
- In cases #1 and #2 the conflict will be recorded when we
- scan the instruction that makes either X or Y become live. */
- record_conflicts (block_start_allocnos, ax);
-
-#ifdef STACK_REGS
- {
- /* Pseudos can't go in stack regs at the start of a basic block
- that is reached by an abnormal edge. */
-
- edge e;
- for (e = b->pred; e ; e = e->pred_next)
- if (e->flags & EDGE_ABNORMAL)
- break;
- if (e != NULL)
- {
- EXECUTE_IF_SET_IN_ALLOCNO_SET (allocnos_live, ax,
- {
- allocno[ax].no_stack_reg = 1;
- });
- for (ax = FIRST_STACK_REG; ax <= LAST_STACK_REG; ax++)
- record_one_conflict (ax);
- }
- }
-#endif
- }
-
- insn = b->head;
-
- /* Scan the code of this basic block, noting which allocnos
- and hard regs are born or die. When one is born,
- record a conflict with all others currently live. */
-
- while (1)
- {
- RTX_CODE code = GET_CODE (insn);
- rtx link;
-
- /* Make regs_set an empty set. */
-
- n_regs_set = 0;
-
- if (code == INSN || code == CALL_INSN || code == JUMP_INSN)
- {
-
-#if 0
- int i = 0;
- for (link = REG_NOTES (insn);
- link && i < NUM_NO_CONFLICT_PAIRS;
- link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_NO_CONFLICT)
- {
- no_conflict_pairs[i].allocno1
- = reg_allocno[REGNO (SET_DEST (PATTERN (insn)))];
- no_conflict_pairs[i].allocno2
- = reg_allocno[REGNO (XEXP (link, 0))];
- i++;
- }
-#endif /* 0 */
-
- /* Mark any registers clobbered by INSN as live,
- so they conflict with the inputs. */
-
- note_stores (PATTERN (insn), mark_reg_clobber, NULL);
-
- /* Mark any registers dead after INSN as dead now. */
-
- for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_DEAD)
- mark_reg_death (XEXP (link, 0));
-
- /* Mark any registers set in INSN as live,
- and mark them as conflicting with all other live regs.
- Clobbers are processed again, so they conflict with
- the registers that are set. */
-
- note_stores (PATTERN (insn), mark_reg_store, NULL);
-
-#ifdef AUTO_INC_DEC
- for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_INC)
- mark_reg_store (XEXP (link, 0), NULL_RTX, NULL);
-#endif
-
- /* If INSN has multiple outputs, then any reg that dies here
- and is used inside of an output
- must conflict with the other outputs.
-
- It is unsafe to use !single_set here since it will ignore an
- unused output. Just because an output is unused does not mean
- the compiler can assume the side effect will not occur.
- Consider if REG appears in the address of an output and we
- reload the output. If we allocate REG to the same hard
- register as an unused output we could set the hard register
- before the output reload insn. */
- if (GET_CODE (PATTERN (insn)) == PARALLEL && multiple_sets (insn))
- for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_DEAD)
- {
- int used_in_output = 0;
- int i;
- rtx reg = XEXP (link, 0);
-
- for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
- {
- rtx set = XVECEXP (PATTERN (insn), 0, i);
- if (GET_CODE (set) == SET
- && GET_CODE (SET_DEST (set)) != REG
- && !rtx_equal_p (reg, SET_DEST (set))
- && reg_overlap_mentioned_p (reg, SET_DEST (set)))
- used_in_output = 1;
- }
- if (used_in_output)
- mark_reg_conflicts (reg);
- }
-
- /* Mark any registers set in INSN and then never used. */
-
- while (n_regs_set-- > 0)
- {
- rtx note = find_regno_note (insn, REG_UNUSED,
- REGNO (regs_set[n_regs_set]));
- if (note)
- mark_reg_death (XEXP (note, 0));
- }
- }
-
- if (insn == b->end)
- break;
- insn = NEXT_INSN (insn);
- }
- }
-
- /* Clean up. */
- free (block_start_allocnos);
- free (regs_set);
-}
/* Expand the preference information by looking for cases where one allocno
dies in an insn that sets an allocno. If those two allocnos don't conflict,
merge any preferences between those allocnos. */
static void
-expand_preferences ()
+expand_preferences (void)
{
rtx insn;
rtx link;
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
if (INSN_P (insn)
&& (set = single_set (insn)) != 0
- && GET_CODE (SET_DEST (set)) == REG
+ && REG_P (SET_DEST (set))
&& reg_allocno[REGNO (SET_DEST (set))] >= 0)
for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
if (REG_NOTE_KIND (link) == REG_DEAD
- && GET_CODE (XEXP (link, 0)) == REG
+ && REG_P (XEXP (link, 0))
&& reg_allocno[REGNO (XEXP (link, 0))] >= 0
- && ! CONFLICTP (reg_allocno[REGNO (SET_DEST (set))],
- reg_allocno[REGNO (XEXP (link, 0))]))
+ && ! conflict_p (reg_allocno[REGNO (SET_DEST (set))],
+ reg_allocno[REGNO (XEXP (link, 0))]))
{
int a1 = reg_allocno[REGNO (SET_DEST (set))];
int a2 = reg_allocno[REGNO (XEXP (link, 0))];
allocno[a1].hard_reg_full_preferences);
}
}
-\f
-/* Prune the preferences for global registers to exclude registers that cannot
- be used.
- Compute `regs_someone_prefers', which is a bitmask of the hard registers
- that are preferred by conflicting registers of lower priority. If possible,
- we will avoid using these registers. */
+
+/* Try to set a preference for an allocno to a hard register.
+ We are passed DEST and SRC which are the operands of a SET. It is known
+ that SRC is a register. If SRC or the first operand of SRC is a register,
+ try to set a preference. If one of the two is a hard register and the other
+ is a pseudo-register, mark the preference.
+
+ Note that we are not as aggressive as local-alloc in trying to tie a
+ pseudo-register to a hard register. */
static void
-prune_preferences ()
+set_preference (rtx dest, rtx src)
{
- int i;
- int num;
- int *allocno_to_order = (int *) xmalloc (max_allocno * sizeof (int));
+ unsigned int src_regno, dest_regno, end_regno;
+ /* Amount to add to the hard regno for SRC, or subtract from that for DEST,
+ to compensate for subregs in SRC or DEST. */
+ int offset = 0;
+ unsigned int i;
+ int copy = 1;
- /* Scan least most important to most important.
- For each allocno, remove from preferences registers that cannot be used,
- either because of conflicts or register type. Then compute all registers
- preferred by each lower-priority register that conflicts. */
+ if (GET_RTX_FORMAT (GET_CODE (src))[0] == 'e')
+ src = XEXP (src, 0), copy = 0;
- for (i = max_allocno - 1; i >= 0; i--)
- {
- HARD_REG_SET temp;
+ /* Get the reg number for both SRC and DEST.
+ If neither is a reg, give up. */
- num = allocno_order[i];
- allocno_to_order[num] = i;
- COPY_HARD_REG_SET (temp, allocno[num].hard_reg_conflicts);
+ if (REG_P (src))
+ src_regno = REGNO (src);
+ else if (GET_CODE (src) == SUBREG && REG_P (SUBREG_REG (src)))
+ {
+ src_regno = REGNO (SUBREG_REG (src));
- if (allocno[num].calls_crossed == 0)
- IOR_HARD_REG_SET (temp, fixed_reg_set);
- else
+ if (REGNO (SUBREG_REG (src)) < FIRST_PSEUDO_REGISTER)
+ offset += subreg_regno_offset (REGNO (SUBREG_REG (src)),
+ GET_MODE (SUBREG_REG (src)),
+ SUBREG_BYTE (src),
+ GET_MODE (src));
+ else
+ offset += (SUBREG_BYTE (src)
+ / REGMODE_NATURAL_SIZE (GET_MODE (src)));
+ }
+ else
+ return;
+
+ if (REG_P (dest))
+ dest_regno = REGNO (dest);
+ else if (GET_CODE (dest) == SUBREG && REG_P (SUBREG_REG (dest)))
+ {
+ dest_regno = REGNO (SUBREG_REG (dest));
+
+ if (REGNO (SUBREG_REG (dest)) < FIRST_PSEUDO_REGISTER)
+ offset -= subreg_regno_offset (REGNO (SUBREG_REG (dest)),
+ GET_MODE (SUBREG_REG (dest)),
+ SUBREG_BYTE (dest),
+ GET_MODE (dest));
+ else
+ offset -= (SUBREG_BYTE (dest)
+ / REGMODE_NATURAL_SIZE (GET_MODE (dest)));
+ }
+ else
+ return;
+
+ /* Convert either or both to hard reg numbers. */
+
+ if (reg_renumber[src_regno] >= 0)
+ src_regno = reg_renumber[src_regno];
+
+ if (reg_renumber[dest_regno] >= 0)
+ dest_regno = reg_renumber[dest_regno];
+
+ /* Now if one is a hard reg and the other is a global pseudo
+ then give the other a preference. */
+
+ if (dest_regno < FIRST_PSEUDO_REGISTER && src_regno >= FIRST_PSEUDO_REGISTER
+ && reg_allocno[src_regno] >= 0)
+ {
+ dest_regno -= offset;
+ if (dest_regno < FIRST_PSEUDO_REGISTER)
+ {
+ if (copy)
+ SET_REGBIT (hard_reg_copy_preferences,
+ reg_allocno[src_regno], dest_regno);
+
+ SET_REGBIT (hard_reg_preferences,
+ reg_allocno[src_regno], dest_regno);
+ end_regno = end_hard_regno (GET_MODE (dest), dest_regno);
+ for (i = dest_regno; i < end_regno; i++)
+ SET_REGBIT (hard_reg_full_preferences, reg_allocno[src_regno], i);
+ }
+ }
+
+ if (src_regno < FIRST_PSEUDO_REGISTER && dest_regno >= FIRST_PSEUDO_REGISTER
+ && reg_allocno[dest_regno] >= 0)
+ {
+ src_regno += offset;
+ if (src_regno < FIRST_PSEUDO_REGISTER)
+ {
+ if (copy)
+ SET_REGBIT (hard_reg_copy_preferences,
+ reg_allocno[dest_regno], src_regno);
+
+ SET_REGBIT (hard_reg_preferences,
+ reg_allocno[dest_regno], src_regno);
+ end_regno = end_hard_regno (GET_MODE (src), src_regno);
+ for (i = src_regno; i < end_regno; i++)
+ SET_REGBIT (hard_reg_full_preferences, reg_allocno[dest_regno], i);
+ }
+ }
+}
+\f
+/* Helper function for set_preferences. */
+static void
+set_preferences_1 (rtx reg, const_rtx setter, void *data ATTRIBUTE_UNUSED)
+{
+ if (GET_CODE (reg) == SUBREG)
+ reg = SUBREG_REG (reg);
+
+ if (!REG_P (reg))
+ return;
+
+ gcc_assert (setter);
+ if (GET_CODE (setter) != CLOBBER)
+ set_preference (reg, SET_SRC (setter));
+}
+\f
+/* Scan all of the insns and initialize the preferences. */
+
+static void
+set_preferences (void)
+{
+ basic_block bb;
+ rtx insn;
+ FOR_EACH_BB (bb)
+ FOR_BB_INSNS_REVERSE (bb, insn)
+ {
+ if (!INSN_P (insn))
+ continue;
+
+ note_stores (PATTERN (insn), set_preferences_1, NULL);
+ }
+}
+
+
+\f
+/* Prune the preferences for global registers to exclude registers that cannot
+ be used.
+
+ Compute `regs_someone_prefers', which is a bitmask of the hard registers
+ that are preferred by conflicting registers of lower priority. If possible,
+ we will avoid using these registers. */
+
+static void
+prune_preferences (void)
+{
+ int i;
+ int num;
+ int *allocno_to_order = XNEWVEC (int, max_allocno);
+
+ /* Scan least most important to most important.
+ For each allocno, remove from preferences registers that cannot be used,
+ either because of conflicts or register type. Then compute all registers
+ preferred by each lower-priority register that conflicts. */
+
+ for (i = max_allocno - 1; i >= 0; i--)
+ {
+ HARD_REG_SET temp;
+
+ num = allocno_order[i];
+ allocno_to_order[num] = i;
+ COPY_HARD_REG_SET (temp, allocno[num].hard_reg_conflicts);
+
+ if (allocno[num].calls_crossed == 0)
+ IOR_HARD_REG_SET (temp, fixed_reg_set);
+ else
IOR_HARD_REG_SET (temp, call_used_reg_set);
IOR_COMPL_HARD_REG_SET
these registers). */
HARD_REG_SET temp, temp2;
int allocno2;
+ adjacency_iter ai;
num = allocno_order[i];
CLEAR_HARD_REG_SET (temp);
CLEAR_HARD_REG_SET (temp2);
- EXECUTE_IF_SET_IN_ALLOCNO_SET (conflicts + num * allocno_row_words,
- allocno2,
+ FOR_EACH_CONFLICT (num, allocno2, ai)
{
if (allocno_to_order[allocno2] > i)
{
IOR_HARD_REG_SET (temp2,
allocno[allocno2].hard_reg_full_preferences);
}
- });
+ }
AND_COMPL_HARD_REG_SET (temp, allocno[num].hard_reg_full_preferences);
IOR_HARD_REG_SET (temp, temp2);
If not, do nothing. */
static void
-find_reg (num, losers, alt_regs_p, accept_call_clobbered, retrying)
- int num;
- HARD_REG_SET losers;
- int alt_regs_p;
- int accept_call_clobbered;
- int retrying;
+find_reg (int num, HARD_REG_SET losers, int alt_regs_p, int accept_call_clobbered, int retrying)
{
int i, best_reg, pass;
HARD_REG_SET used, used1, used2;
IOR_HARD_REG_SET (used1, losers);
IOR_COMPL_HARD_REG_SET (used1, reg_class_contents[(int) class]);
+
+#ifdef EH_RETURN_DATA_REGNO
+ if (allocno[num].no_eh_reg)
+ {
+ unsigned int j;
+ for (j = 0; ; ++j)
+ {
+ unsigned int regno = EH_RETURN_DATA_REGNO (j);
+ if (regno == INVALID_REGNUM)
+ break;
+ SET_HARD_REG_BIT (used1, regno);
+ }
+ }
+#endif
+
COPY_HARD_REG_SET (used2, used1);
IOR_HARD_REG_SET (used1, allocno[num].hard_reg_conflicts);
|| ! HARD_REGNO_CALL_PART_CLOBBERED (regno, mode)))
{
int j;
- int lim = regno + HARD_REGNO_NREGS (regno, mode);
+ int lim = end_hard_regno (mode, regno);
for (j = regno + 1;
(j < lim
&& ! TEST_HARD_REG_BIT (used, j));
preferred registers. */
AND_COMPL_HARD_REG_SET (allocno[num].hard_reg_copy_preferences, used);
- GO_IF_HARD_REG_SUBSET (allocno[num].hard_reg_copy_preferences,
- reg_class_contents[(int) NO_REGS], no_copy_prefs);
-
- if (best_reg >= 0)
+ if (!hard_reg_set_empty_p (allocno[num].hard_reg_copy_preferences)
+ && best_reg >= 0)
{
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
if (TEST_HARD_REG_BIT (allocno[num].hard_reg_copy_preferences, i)
REGNO_REG_CLASS (i))))
{
int j;
- int lim = i + HARD_REGNO_NREGS (i, mode);
+ int lim = end_hard_regno (mode, i);
for (j = i + 1;
(j < lim
&& ! TEST_HARD_REG_BIT (used, j)
&& (REGNO_REG_CLASS (j)
- == REGNO_REG_CLASS (best_reg + (j - i))
+ == REGNO_REG_CLASS (best_reg + (j - i))
|| reg_class_subset_p (REGNO_REG_CLASS (j),
REGNO_REG_CLASS (best_reg + (j - i)))
|| reg_class_subset_p (REGNO_REG_CLASS (best_reg + (j - i)),
}
}
}
- no_copy_prefs:
AND_COMPL_HARD_REG_SET (allocno[num].hard_reg_preferences, used);
- GO_IF_HARD_REG_SUBSET (allocno[num].hard_reg_preferences,
- reg_class_contents[(int) NO_REGS], no_prefs);
-
- if (best_reg >= 0)
+ if (!hard_reg_set_empty_p (allocno[num].hard_reg_preferences)
+ && best_reg >= 0)
{
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
if (TEST_HARD_REG_BIT (allocno[num].hard_reg_preferences, i)
REGNO_REG_CLASS (i))))
{
int j;
- int lim = i + HARD_REGNO_NREGS (i, mode);
+ int lim = end_hard_regno (mode, i);
for (j = i + 1;
(j < lim
&& ! TEST_HARD_REG_BIT (used, j)
&& (REGNO_REG_CLASS (j)
- == REGNO_REG_CLASS (best_reg + (j - i))
+ == REGNO_REG_CLASS (best_reg + (j - i))
|| reg_class_subset_p (REGNO_REG_CLASS (j),
REGNO_REG_CLASS (best_reg + (j - i)))
|| reg_class_subset_p (REGNO_REG_CLASS (best_reg + (j - i)),
{
/* Did not find a register. If it would be profitable to
allocate a call-clobbered register and save and restore it
- around calls, do that. */
+ around calls, do that. Don't do this if it crosses any calls
+ that might throw. */
if (! accept_call_clobbered
&& allocno[num].calls_crossed != 0
- && CALLER_SAVE_PROFITABLE (allocno[num].n_refs,
- allocno[num].calls_crossed))
+ && allocno[num].throwing_calls_crossed == 0
+ && CALLER_SAVE_PROFITABLE (optimize_size ? allocno[num].n_refs : allocno[num].freq,
+ optimize_size ? allocno[num].calls_crossed
+ : allocno[num].freq_calls_crossed))
{
HARD_REG_SET new_losers;
if (! losers)
so we can use it instead. */
if (best_reg < 0 && !retrying
/* Let's not bother with multi-reg allocnos. */
- && allocno[num].size == 1)
+ && allocno[num].size == 1
+ && REG_BASIC_BLOCK (allocno[num].reg) == REG_BLOCK_GLOBAL)
{
/* Count from the end, to find the least-used ones first. */
for (i = FIRST_PSEUDO_REGISTER - 1; i >= 0; i--)
register, but the check of allocno[num].size above
was not enough. Sometimes we need more than one
register for a single-word value. */
- && HARD_REGNO_NREGS (regno, mode) == 1
+ && hard_regno_nregs[regno][mode] == 1
&& (allocno[num].calls_crossed == 0
|| accept_call_clobbered
|| ! HARD_REGNO_CALL_PART_CLOBBERED (regno, mode))
variables so as to avoid excess precision problems that occur
on an i386-unknown-sysv4.2 (unixware) host. */
- double tmp1 = ((double) local_reg_freq[regno]
+ double tmp1 = ((double) local_reg_freq[regno] * local_reg_n_refs[regno]
/ local_reg_live_length[regno]);
- double tmp2 = ((double) allocno[num].freq
+ double tmp2 = ((double) allocno[num].freq * allocno[num].n_refs
/ allocno[num].live_length);
if (tmp1 < tmp2)
/* Hard reg REGNO was used less in total by local regs
than it would be used by this one allocno! */
int k;
+ if (dump_file)
+ {
+ fprintf (dump_file, "Regno %d better for global %d, ",
+ regno, allocno[num].reg);
+ fprintf (dump_file, "fr:%d, ll:%d, nr:%d ",
+ allocno[num].freq, allocno[num].live_length,
+ allocno[num].n_refs);
+ fprintf (dump_file, "(was: fr:%d, ll:%d, nr:%d)\n",
+ local_reg_freq[regno],
+ local_reg_live_length[regno],
+ local_reg_n_refs[regno]);
+ }
+
for (k = 0; k < max_regno; k++)
if (reg_renumber[k] >= 0)
{
int r = reg_renumber[k];
int endregno
- = r + HARD_REGNO_NREGS (r, PSEUDO_REGNO_MODE (k));
+ = end_hard_regno (PSEUDO_REGNO_MODE (k), r);
if (regno >= r && regno < endregno)
- reg_renumber[k] = -1;
+ {
+ if (dump_file)
+ fprintf (dump_file,
+ "Local Reg %d now on stack\n", k);
+ reg_renumber[k] = -1;
+ }
}
best_reg = regno;
{
int lim, j;
HARD_REG_SET this_reg;
+ adjacency_iter ai;
/* Yes. Record it as the hard register of this pseudo-reg. */
reg_renumber[allocno[num].reg] = best_reg;
- /* Also of any pseudo-regs that share with it. */
- if (reg_may_share[allocno[num].reg])
- for (j = FIRST_PSEUDO_REGISTER; j < max_regno; j++)
- if (reg_allocno[j] == num)
- reg_renumber[j] = best_reg;
/* Make a set of the hard regs being allocated. */
CLEAR_HARD_REG_SET (this_reg);
- lim = best_reg + HARD_REGNO_NREGS (best_reg, mode);
+ lim = end_hard_regno (mode, best_reg);
for (j = best_reg; j < lim; j++)
{
SET_HARD_REG_BIT (this_reg, j);
}
/* For each other pseudo-reg conflicting with this one,
mark it as conflicting with the hard regs this one occupies. */
- lim = num;
- EXECUTE_IF_SET_IN_ALLOCNO_SET (conflicts + lim * allocno_row_words, j,
+ FOR_EACH_CONFLICT (num, j, ai)
{
IOR_HARD_REG_SET (allocno[j].hard_reg_conflicts, this_reg);
- });
+ }
}
}
\f
If FORBIDDEN_REGS is zero, no regs are forbidden. */
void
-retry_global_alloc (regno, forbidden_regs)
- int regno;
- HARD_REG_SET forbidden_regs;
+retry_global_alloc (int regno, HARD_REG_SET forbidden_regs)
{
int alloc_no = reg_allocno[regno];
if (alloc_no >= 0)
show the hard register, and mark that register live. */
if (reg_renumber[regno] >= 0)
{
- REGNO (regno_reg_rtx[regno]) = reg_renumber[regno];
+ SET_REGNO (regno_reg_rtx[regno], reg_renumber[regno]);
mark_home_live (regno);
}
}
}
\f
-/* Record a conflict between register REGNO
- and everything currently live.
- REGNO must not be a pseudo reg that was allocated
- by local_alloc; such numbers must be translated through
- reg_renumber before calling here. */
-
-static void
-record_one_conflict (regno)
- int regno;
-{
- int j;
-
- if (regno < FIRST_PSEUDO_REGISTER)
- /* When a hard register becomes live,
- record conflicts with live pseudo regs. */
- EXECUTE_IF_SET_IN_ALLOCNO_SET (allocnos_live, j,
- {
- SET_HARD_REG_BIT (allocno[j].hard_reg_conflicts, regno);
- });
- else
- /* When a pseudo-register becomes live,
- record conflicts first with hard regs,
- then with other pseudo regs. */
- {
- int ialloc = reg_allocno[regno];
- int ialloc_prod = ialloc * allocno_row_words;
-
- IOR_HARD_REG_SET (allocno[ialloc].hard_reg_conflicts, hard_regs_live);
- for (j = allocno_row_words - 1; j >= 0; j--)
- {
-#if 0
- int k;
- for (k = 0; k < n_no_conflict_pairs; k++)
- if (! ((j == no_conflict_pairs[k].allocno1
- && ialloc == no_conflict_pairs[k].allocno2)
- ||
- (j == no_conflict_pairs[k].allocno2
- && ialloc == no_conflict_pairs[k].allocno1)))
-#endif /* 0 */
- conflicts[ialloc_prod + j] |= allocnos_live[j];
- }
- }
-}
-
-/* Record all allocnos currently live as conflicting
- with all hard regs currently live.
-
- ALLOCNO_VEC is a vector of LEN allocnos, all allocnos that
- are currently live. Their bits are also flagged in allocnos_live. */
-
-static void
-record_conflicts (allocno_vec, len)
- int *allocno_vec;
- int len;
-{
- while (--len >= 0)
- IOR_HARD_REG_SET (allocno[allocno_vec[len]].hard_reg_conflicts,
- hard_regs_live);
-}
-
-/* If CONFLICTP (i, j) is true, make sure CONFLICTP (j, i) is also true. */
-static void
-mirror_conflicts ()
-{
- int i, j;
- int rw = allocno_row_words;
- int rwb = rw * INT_BITS;
- INT_TYPE *p = conflicts;
- INT_TYPE *q0 = conflicts, *q1, *q2;
- unsigned INT_TYPE mask;
-
- for (i = max_allocno - 1, mask = 1; i >= 0; i--, mask <<= 1)
- {
- if (! mask)
- {
- mask = 1;
- q0++;
- }
- for (j = allocno_row_words - 1, q1 = q0; j >= 0; j--, q1 += rwb)
- {
- unsigned INT_TYPE word;
-
- for (word = (unsigned INT_TYPE) *p++, q2 = q1; word;
- word >>= 1, q2 += rw)
- {
- if (word & 1)
- *q2 |= mask;
- }
- }
- }
-}
-\f
-/* Handle the case where REG is set by the insn being scanned,
- during the forward scan to accumulate conflicts.
- Store a 1 in regs_live or allocnos_live for this register, record how many
- consecutive hardware registers it actually needs,
- and record a conflict with all other registers already live.
-
- Note that even if REG does not remain alive after this insn,
- we must mark it here as live, to ensure a conflict between
- REG and any other regs set in this insn that really do live.
- This is because those other regs could be considered after this.
-
- REG might actually be something other than a register;
- if so, we do nothing.
-
- SETTER is 0 if this register was modified by an auto-increment (i.e.,
- a REG_INC note was found for it). */
-
-static void
-mark_reg_store (reg, setter, data)
- rtx reg, setter;
- void *data ATTRIBUTE_UNUSED;
-{
- int regno;
-
- if (GET_CODE (reg) == SUBREG)
- reg = SUBREG_REG (reg);
-
- if (GET_CODE (reg) != REG)
- return;
-
- regs_set[n_regs_set++] = reg;
-
- if (setter && GET_CODE (setter) != CLOBBER)
- set_preference (reg, SET_SRC (setter));
-
- regno = REGNO (reg);
-
- /* Either this is one of the max_allocno pseudo regs not allocated,
- or it is or has a hardware reg. First handle the pseudo-regs. */
- if (regno >= FIRST_PSEUDO_REGISTER)
- {
- if (reg_allocno[regno] >= 0)
- {
- SET_ALLOCNO_LIVE (reg_allocno[regno]);
- record_one_conflict (regno);
- }
- }
-
- if (reg_renumber[regno] >= 0)
- regno = reg_renumber[regno];
-
- /* Handle hardware regs (and pseudos allocated to hard regs). */
- if (regno < FIRST_PSEUDO_REGISTER && ! fixed_regs[regno])
- {
- int last = regno + HARD_REGNO_NREGS (regno, GET_MODE (reg));
- while (regno < last)
- {
- record_one_conflict (regno);
- SET_HARD_REG_BIT (hard_regs_live, regno);
- regno++;
- }
- }
-}
-\f
-/* Like mark_reg_set except notice just CLOBBERs; ignore SETs. */
-
-static void
-mark_reg_clobber (reg, setter, data)
- rtx reg, setter;
- void *data ATTRIBUTE_UNUSED;
-{
- if (GET_CODE (setter) == CLOBBER)
- mark_reg_store (reg, setter, data);
-}
-
-/* Record that REG has conflicts with all the regs currently live.
- Do not mark REG itself as live. */
-
-static void
-mark_reg_conflicts (reg)
- rtx reg;
-{
- int regno;
-
- if (GET_CODE (reg) == SUBREG)
- reg = SUBREG_REG (reg);
-
- if (GET_CODE (reg) != REG)
- return;
-
- regno = REGNO (reg);
-
- /* Either this is one of the max_allocno pseudo regs not allocated,
- or it is or has a hardware reg. First handle the pseudo-regs. */
- if (regno >= FIRST_PSEUDO_REGISTER)
- {
- if (reg_allocno[regno] >= 0)
- record_one_conflict (regno);
- }
-
- if (reg_renumber[regno] >= 0)
- regno = reg_renumber[regno];
-
- /* Handle hardware regs (and pseudos allocated to hard regs). */
- if (regno < FIRST_PSEUDO_REGISTER && ! fixed_regs[regno])
- {
- int last = regno + HARD_REGNO_NREGS (regno, GET_MODE (reg));
- while (regno < last)
- {
- record_one_conflict (regno);
- regno++;
- }
- }
-}
-\f
-/* Mark REG as being dead (following the insn being scanned now).
- Store a 0 in regs_live or allocnos_live for this register. */
-
-static void
-mark_reg_death (reg)
- rtx reg;
-{
- int regno = REGNO (reg);
-
- /* Either this is one of the max_allocno pseudo regs not allocated,
- or it is a hardware reg. First handle the pseudo-regs. */
- if (regno >= FIRST_PSEUDO_REGISTER)
- {
- if (reg_allocno[regno] >= 0)
- CLEAR_ALLOCNO_LIVE (reg_allocno[regno]);
- }
-
- /* For pseudo reg, see if it has been assigned a hardware reg. */
- if (reg_renumber[regno] >= 0)
- regno = reg_renumber[regno];
-
- /* Handle hardware regs (and pseudos allocated to hard regs). */
- if (regno < FIRST_PSEUDO_REGISTER && ! fixed_regs[regno])
- {
- /* Pseudo regs already assigned hardware regs are treated
- almost the same as explicit hardware regs. */
- int last = regno + HARD_REGNO_NREGS (regno, GET_MODE (reg));
- while (regno < last)
- {
- CLEAR_HARD_REG_BIT (hard_regs_live, regno);
- regno++;
- }
- }
-}
-
-/* Mark hard reg REGNO as currently live, assuming machine mode MODE
- for the value stored in it. MODE determines how many consecutive
- registers are actually in use. Do not record conflicts;
- it is assumed that the caller will do that. */
-
-static void
-mark_reg_live_nc (regno, mode)
- int regno;
- enum machine_mode mode;
-{
- int last = regno + HARD_REGNO_NREGS (regno, mode);
- while (regno < last)
- {
- SET_HARD_REG_BIT (hard_regs_live, regno);
- regno++;
- }
-}
-\f
-/* Try to set a preference for an allocno to a hard register.
- We are passed DEST and SRC which are the operands of a SET. It is known
- that SRC is a register. If SRC or the first operand of SRC is a register,
- try to set a preference. If one of the two is a hard register and the other
- is a pseudo-register, mark the preference.
-
- Note that we are not as aggressive as local-alloc in trying to tie a
- pseudo-register to a hard register. */
-
-static void
-set_preference (dest, src)
- rtx dest, src;
-{
- unsigned int src_regno, dest_regno;
- /* Amount to add to the hard regno for SRC, or subtract from that for DEST,
- to compensate for subregs in SRC or DEST. */
- int offset = 0;
- unsigned int i;
- int copy = 1;
-
- if (GET_RTX_FORMAT (GET_CODE (src))[0] == 'e')
- src = XEXP (src, 0), copy = 0;
-
- /* Get the reg number for both SRC and DEST.
- If neither is a reg, give up. */
-
- if (GET_CODE (src) == REG)
- src_regno = REGNO (src);
- else if (GET_CODE (src) == SUBREG && GET_CODE (SUBREG_REG (src)) == REG)
- {
- src_regno = REGNO (SUBREG_REG (src));
-
- if (REGNO (SUBREG_REG (src)) < FIRST_PSEUDO_REGISTER)
- offset += subreg_regno_offset (REGNO (SUBREG_REG (src)),
- GET_MODE (SUBREG_REG (src)),
- SUBREG_BYTE (src),
- GET_MODE (src));
- else
- offset += (SUBREG_BYTE (src)
- / REGMODE_NATURAL_SIZE (GET_MODE (src)));
- }
- else
- return;
-
- if (GET_CODE (dest) == REG)
- dest_regno = REGNO (dest);
- else if (GET_CODE (dest) == SUBREG && GET_CODE (SUBREG_REG (dest)) == REG)
- {
- dest_regno = REGNO (SUBREG_REG (dest));
-
- if (REGNO (SUBREG_REG (dest)) < FIRST_PSEUDO_REGISTER)
- offset -= subreg_regno_offset (REGNO (SUBREG_REG (dest)),
- GET_MODE (SUBREG_REG (dest)),
- SUBREG_BYTE (dest),
- GET_MODE (dest));
- else
- offset -= (SUBREG_BYTE (dest)
- / REGMODE_NATURAL_SIZE (GET_MODE (dest)));
- }
- else
- return;
-
- /* Convert either or both to hard reg numbers. */
-
- if (reg_renumber[src_regno] >= 0)
- src_regno = reg_renumber[src_regno];
-
- if (reg_renumber[dest_regno] >= 0)
- dest_regno = reg_renumber[dest_regno];
-
- /* Now if one is a hard reg and the other is a global pseudo
- then give the other a preference. */
-
- if (dest_regno < FIRST_PSEUDO_REGISTER && src_regno >= FIRST_PSEUDO_REGISTER
- && reg_allocno[src_regno] >= 0)
- {
- dest_regno -= offset;
- if (dest_regno < FIRST_PSEUDO_REGISTER)
- {
- if (copy)
- SET_REGBIT (hard_reg_copy_preferences,
- reg_allocno[src_regno], dest_regno);
-
- SET_REGBIT (hard_reg_preferences,
- reg_allocno[src_regno], dest_regno);
- for (i = dest_regno;
- i < dest_regno + HARD_REGNO_NREGS (dest_regno, GET_MODE (dest));
- i++)
- SET_REGBIT (hard_reg_full_preferences, reg_allocno[src_regno], i);
- }
- }
-
- if (src_regno < FIRST_PSEUDO_REGISTER && dest_regno >= FIRST_PSEUDO_REGISTER
- && reg_allocno[dest_regno] >= 0)
- {
- src_regno += offset;
- if (src_regno < FIRST_PSEUDO_REGISTER)
- {
- if (copy)
- SET_REGBIT (hard_reg_copy_preferences,
- reg_allocno[dest_regno], src_regno);
-
- SET_REGBIT (hard_reg_preferences,
- reg_allocno[dest_regno], src_regno);
- for (i = src_regno;
- i < src_regno + HARD_REGNO_NREGS (src_regno, GET_MODE (src));
- i++)
- SET_REGBIT (hard_reg_full_preferences, reg_allocno[dest_regno], i);
- }
- }
-}
-\f
/* Indicate that hard register number FROM was eliminated and replaced with
an offset from hard register number TO. The status of hard registers live
at the start of a basic block is updated by replacing a use of FROM with
a use of TO. */
void
-mark_elimination (from, to)
- int from, to;
+mark_elimination (int from, int to)
{
basic_block bb;
FOR_EACH_BB (bb)
{
- regset r = bb->global_live_at_start;
+ regset r = DF_LIVE_IN (bb);
if (REGNO_REG_SET_P (r, from))
{
CLEAR_REGNO_REG_SET (r, from);
}
}
\f
-/* Used for communication between the following functions. Holds the
- current life information. */
-static regset live_relevant_regs;
+/* Print chain C to FILE. */
-/* Record in live_relevant_regs and REGS_SET that register REG became live.
- This is called via note_stores. */
static void
-reg_becomes_live (reg, setter, regs_set)
- rtx reg;
- rtx setter ATTRIBUTE_UNUSED;
- void *regs_set;
+print_insn_chain (FILE *file, struct insn_chain *c)
{
- int regno;
+ fprintf (file, "insn=%d, ", INSN_UID(c->insn));
+ bitmap_print (file, &c->live_throughout, "live_throughout: ", ", ");
+ bitmap_print (file, &c->dead_or_set, "dead_or_set: ", "\n");
+}
- if (GET_CODE (reg) == SUBREG)
- reg = SUBREG_REG (reg);
- if (GET_CODE (reg) != REG)
- return;
+/* Print all reload_insn_chains to FILE. */
- regno = REGNO (reg);
- if (regno < FIRST_PSEUDO_REGISTER)
- {
- int nregs = HARD_REGNO_NREGS (regno, GET_MODE (reg));
- while (nregs-- > 0)
- {
- SET_REGNO_REG_SET (live_relevant_regs, regno);
- if (! fixed_regs[regno])
- SET_REGNO_REG_SET ((regset) regs_set, regno);
- regno++;
- }
- }
- else if (reg_renumber[regno] >= 0)
- {
- SET_REGNO_REG_SET (live_relevant_regs, regno);
- SET_REGNO_REG_SET ((regset) regs_set, regno);
- }
-}
-
-/* Record in live_relevant_regs that register REGNO died. */
static void
-reg_dies (regno, mode, chain)
- int regno;
- enum machine_mode mode;
- struct insn_chain *chain;
+print_insn_chains (FILE *file)
{
- if (regno < FIRST_PSEUDO_REGISTER)
- {
- int nregs = HARD_REGNO_NREGS (regno, mode);
- while (nregs-- > 0)
- {
- CLEAR_REGNO_REG_SET (live_relevant_regs, regno);
- if (! fixed_regs[regno])
- SET_REGNO_REG_SET (&chain->dead_or_set, regno);
- regno++;
- }
- }
- else
- {
- CLEAR_REGNO_REG_SET (live_relevant_regs, regno);
- if (reg_renumber[regno] >= 0)
- SET_REGNO_REG_SET (&chain->dead_or_set, regno);
- }
+ struct insn_chain *c;
+ for (c = reload_insn_chain; c ; c = c->next)
+ print_insn_chain (file, c);
}
+
/* Walk the insns of the current function and build reload_insn_chain,
and record register life information. */
-void
-build_insn_chain (first)
- rtx first;
+
+static void
+build_insn_chain (void)
{
+ unsigned int i;
struct insn_chain **p = &reload_insn_chain;
- struct insn_chain *prev = 0;
- basic_block b = ENTRY_BLOCK_PTR->next_bb;
- regset_head live_relevant_regs_head;
+ basic_block bb;
+ struct insn_chain *c = NULL;
+ struct insn_chain *next = NULL;
+ bitmap live_relevant_regs = BITMAP_ALLOC (NULL);
+ bitmap elim_regset = BITMAP_ALLOC (NULL);
+ /* live_subregs is a vector used to keep accurate information about
+ which hardregs are live in multiword pseudos. live_subregs and
+ live_subregs_used are indexed by pseudo number. The live_subreg
+ entry for a particular pseudo is only used if the corresponding
+ element is non zero in live_subregs_used. The value in
+ live_subregs_used is number of bytes that the pseudo can
+ occupy. */
+ sbitmap *live_subregs = XCNEWVEC (sbitmap, max_regno);
+ int *live_subregs_used = XNEWVEC (int, max_regno);
- live_relevant_regs = INITIALIZE_REG_SET (live_relevant_regs_head);
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (TEST_HARD_REG_BIT (eliminable_regset, i))
+ bitmap_set_bit (elim_regset, i);
- for (; first; first = NEXT_INSN (first))
+ FOR_EACH_BB_REVERSE (bb)
{
- struct insn_chain *c;
+ bitmap_iterator bi;
+ rtx insn;
+
+ CLEAR_REG_SET (live_relevant_regs);
+ memset (live_subregs_used, 0, max_regno * sizeof (int));
+
+ EXECUTE_IF_SET_IN_BITMAP (df_get_live_out (bb), 0, i, bi)
+ {
+ if (i >= FIRST_PSEUDO_REGISTER)
+ break;
+ bitmap_set_bit (live_relevant_regs, i);
+ }
- if (first == b->head)
+ EXECUTE_IF_SET_IN_BITMAP (df_get_live_out (bb), FIRST_PSEUDO_REGISTER, i, bi)
{
- int i;
-
- CLEAR_REG_SET (live_relevant_regs);
-
- EXECUTE_IF_SET_IN_BITMAP
- (b->global_live_at_start, 0, i,
- {
- if (i < FIRST_PSEUDO_REGISTER
- ? ! TEST_HARD_REG_BIT (eliminable_regset, i)
- : reg_renumber[i] >= 0)
- SET_REGNO_REG_SET (live_relevant_regs, i);
- });
+ if (reg_renumber[i] >= 0)
+ bitmap_set_bit (live_relevant_regs, i);
}
- if (GET_CODE (first) != NOTE && GET_CODE (first) != BARRIER)
+ FOR_BB_INSNS_REVERSE (bb, insn)
{
- c = new_insn_chain ();
- c->prev = prev;
- prev = c;
- *p = c;
- p = &c->next;
- c->insn = first;
- c->block = b->index;
-
- if (INSN_P (first))
+ if (!NOTE_P (insn) && !BARRIER_P (insn))
{
- rtx link;
-
- /* Mark the death of everything that dies in this instruction. */
-
- for (link = REG_NOTES (first); link; link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_DEAD
- && GET_CODE (XEXP (link, 0)) == REG)
- reg_dies (REGNO (XEXP (link, 0)), GET_MODE (XEXP (link, 0)),
- c);
-
- COPY_REG_SET (&c->live_throughout, live_relevant_regs);
+ unsigned int uid = INSN_UID (insn);
+ struct df_ref **def_rec;
+ struct df_ref **use_rec;
+
+ c = new_insn_chain ();
+ c->next = next;
+ next = c;
+ *p = c;
+ p = &c->prev;
+
+ c->insn = insn;
+ c->block = bb->index;
+
+ if (INSN_P (insn))
+ for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
+ {
+ struct df_ref *def = *def_rec;
+ unsigned int regno = DF_REF_REGNO (def);
+
+ /* Ignore may clobbers because these are generated
+ from calls. However, every other kind of def is
+ added to dead_or_set. */
+ if (!DF_REF_FLAGS_IS_SET (def, DF_REF_MAY_CLOBBER))
+ {
+ if (regno < FIRST_PSEUDO_REGISTER)
+ {
+ if (!fixed_regs[regno])
+ bitmap_set_bit (&c->dead_or_set, regno);
+ }
+ else if (reg_renumber[regno] >= 0)
+ bitmap_set_bit (&c->dead_or_set, regno);
+ }
- /* Mark everything born in this instruction as live. */
+ if ((regno < FIRST_PSEUDO_REGISTER || reg_renumber[regno] >= 0)
+ && (!DF_REF_FLAGS_IS_SET (def, DF_REF_CONDITIONAL)))
+ {
+ rtx reg = DF_REF_REG (def);
+
+ /* We can model subregs, but not if they are
+ wrapped in ZERO_EXTRACTS. */
+ if (GET_CODE (reg) == SUBREG
+ && !DF_REF_FLAGS_IS_SET (def, DF_REF_ZERO_EXTRACT))
+ {
+ unsigned int start = SUBREG_BYTE (reg);
+ unsigned int last = start
+ + GET_MODE_SIZE (GET_MODE (reg));
+
+ ra_init_live_subregs (bitmap_bit_p (live_relevant_regs,
+ regno),
+ live_subregs,
+ live_subregs_used,
+ regno, reg);
+
+ if (!DF_REF_FLAGS_IS_SET
+ (def, DF_REF_STRICT_LOW_PART))
+ {
+ /* Expand the range to cover entire words.
+ Bytes added here are "don't care". */
+ start = start / UNITS_PER_WORD * UNITS_PER_WORD;
+ last = ((last + UNITS_PER_WORD - 1)
+ / UNITS_PER_WORD * UNITS_PER_WORD);
+ }
+
+ /* Ignore the paradoxical bits. */
+ if ((int)last > live_subregs_used[regno])
+ last = live_subregs_used[regno];
+
+ while (start < last)
+ {
+ RESET_BIT (live_subregs[regno], start);
+ start++;
+ }
+
+ if (sbitmap_empty_p (live_subregs[regno]))
+ {
+ live_subregs_used[regno] = 0;
+ bitmap_clear_bit (live_relevant_regs, regno);
+ }
+ else
+ /* Set live_relevant_regs here because
+ that bit has to be true to get us to
+ look at the live_subregs fields. */
+ bitmap_set_bit (live_relevant_regs, regno);
+ }
+ else
+ {
+ /* DF_REF_PARTIAL is generated for
+ subregs, STRICT_LOW_PART, and
+ ZERO_EXTRACT. We handle the subreg
+ case above so here we have to keep from
+ modeling the def as a killing def. */
+ if (!DF_REF_FLAGS_IS_SET (def, DF_REF_PARTIAL))
+ {
+ bitmap_clear_bit (live_relevant_regs, regno);
+ live_subregs_used[regno] = 0;
+ }
+ }
+ }
+ }
+
+ bitmap_and_compl_into (live_relevant_regs, elim_regset);
+ bitmap_copy (&c->live_throughout, live_relevant_regs);
- note_stores (PATTERN (first), reg_becomes_live,
- &c->dead_or_set);
+ if (INSN_P (insn))
+ for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
+ {
+ struct df_ref *use = *use_rec;
+ unsigned int regno = DF_REF_REGNO (use);
+ rtx reg = DF_REF_REG (use);
+
+ /* DF_REF_READ_WRITE on a use means that this use
+ is fabricated from a def that is a partial set
+ to a multiword reg. Here, we only model the
+ subreg case that is not wrapped in ZERO_EXTRACT
+ precisely so we do not need to look at the
+ fabricated use. */
+ if (DF_REF_FLAGS_IS_SET (use, DF_REF_READ_WRITE)
+ && !DF_REF_FLAGS_IS_SET (use, DF_REF_ZERO_EXTRACT)
+ && DF_REF_FLAGS_IS_SET (use, DF_REF_SUBREG))
+ continue;
+
+ /* Add the last use of each var to dead_or_set. */
+ if (!bitmap_bit_p (live_relevant_regs, regno))
+ {
+ if (regno < FIRST_PSEUDO_REGISTER)
+ {
+ if (!fixed_regs[regno])
+ bitmap_set_bit (&c->dead_or_set, regno);
+ }
+ else if (reg_renumber[regno] >= 0)
+ bitmap_set_bit (&c->dead_or_set, regno);
+ }
+
+ if (regno < FIRST_PSEUDO_REGISTER || reg_renumber[regno] >= 0)
+ {
+ if (GET_CODE (reg) == SUBREG
+ && !DF_REF_FLAGS_IS_SET (use,
+ DF_REF_SIGN_EXTRACT | DF_REF_ZERO_EXTRACT))
+ {
+ unsigned int start = SUBREG_BYTE (reg);
+ unsigned int last = start
+ + GET_MODE_SIZE (GET_MODE (reg));
+
+ ra_init_live_subregs (bitmap_bit_p (live_relevant_regs,
+ regno),
+ live_subregs,
+ live_subregs_used,
+ regno, reg);
+
+ /* Ignore the paradoxical bits. */
+ if ((int)last > live_subregs_used[regno])
+ last = live_subregs_used[regno];
+
+ while (start < last)
+ {
+ SET_BIT (live_subregs[regno], start);
+ start++;
+ }
+ }
+ else
+ /* Resetting the live_subregs_used is
+ effectively saying do not use the subregs
+ because we are reading the whole
+ pseudo. */
+ live_subregs_used[regno] = 0;
+ bitmap_set_bit (live_relevant_regs, regno);
+ }
+ }
}
- else
- COPY_REG_SET (&c->live_throughout, live_relevant_regs);
+ }
- if (INSN_P (first))
+ /* FIXME!! The following code is a disaster. Reload needs to see the
+ labels and jump tables that are just hanging out in between
+ the basic blocks. See pr33676. */
+ insn = BB_HEAD (bb);
+
+ /* Skip over the barriers and cruft. */
+ while (insn && (BARRIER_P (insn) || NOTE_P (insn)
+ || BLOCK_FOR_INSN (insn) == bb))
+ insn = PREV_INSN (insn);
+
+ /* While we add anything except barriers and notes, the focus is
+ to get the labels and jump tables into the
+ reload_insn_chain. */
+ while (insn)
+ {
+ if (!NOTE_P (insn) && !BARRIER_P (insn))
{
- rtx link;
-
- /* Mark anything that is set in this insn and then unused as dying. */
-
- for (link = REG_NOTES (first); link; link = XEXP (link, 1))
- if (REG_NOTE_KIND (link) == REG_UNUSED
- && GET_CODE (XEXP (link, 0)) == REG)
- reg_dies (REGNO (XEXP (link, 0)), GET_MODE (XEXP (link, 0)),
- c);
- }
+ if (BLOCK_FOR_INSN (insn))
+ break;
+
+ c = new_insn_chain ();
+ c->next = next;
+ next = c;
+ *p = c;
+ p = &c->prev;
+
+ /* The block makes no sense here, but it is what the old
+ code did. */
+ c->block = bb->index;
+ c->insn = insn;
+ bitmap_copy (&c->live_throughout, live_relevant_regs);
+ }
+ insn = PREV_INSN (insn);
}
+ }
- if (first == b->end)
- b = b->next_bb;
+ for (i = 0; i < (unsigned int) max_regno; i++)
+ if (live_subregs[i])
+ free (live_subregs[i]);
- /* Stop after we pass the end of the last basic block. Verify that
- no real insns are after the end of the last basic block.
+ reload_insn_chain = c;
+ *p = NULL;
- We may want to reorganize the loop somewhat since this test should
- always be the right exit test. Allow an ADDR_VEC or ADDR_DIF_VEC if
- the previous real insn is a JUMP_INSN. */
- if (b == EXIT_BLOCK_PTR)
- {
- for (first = NEXT_INSN (first) ; first; first = NEXT_INSN (first))
- if (INSN_P (first)
- && GET_CODE (PATTERN (first)) != USE
- && ! ((GET_CODE (PATTERN (first)) == ADDR_VEC
- || GET_CODE (PATTERN (first)) == ADDR_DIFF_VEC)
- && prev_real_insn (first) != 0
- && GET_CODE (prev_real_insn (first)) == JUMP_INSN))
- abort ();
- break;
- }
- }
- FREE_REG_SET (live_relevant_regs);
- *p = 0;
+ free (live_subregs);
+ free (live_subregs_used);
+ BITMAP_FREE (live_relevant_regs);
+ BITMAP_FREE (elim_regset);
+
+ if (dump_file)
+ print_insn_chains (dump_file);
}
\f
/* Print debugging trace information if -dg switch is given,
showing the information on which the allocation decisions are based. */
static void
-dump_conflicts (file)
- FILE *file;
+dump_conflicts (FILE *file)
{
int i;
+ int regno;
int has_preferences;
int nregs;
nregs = 0;
nregs++;
}
fprintf (file, ";; %d regs to allocate:", nregs);
- for (i = 0; i < max_allocno; i++)
- {
- int j;
- if (reg_renumber[allocno[allocno_order[i]].reg] >= 0)
- continue;
- fprintf (file, " %d", allocno[allocno_order[i]].reg);
- for (j = 0; j < max_regno; j++)
- if (reg_allocno[j] == allocno_order[i]
- && j != allocno[allocno_order[i]].reg)
- fprintf (file, "+%d", j);
- if (allocno[allocno_order[i]].size != 1)
- fprintf (file, " (%d)", allocno[allocno_order[i]].size);
- }
+ for (regno = 0; regno < max_regno; regno++)
+ if ((i = reg_allocno[regno]) >= 0)
+ {
+ int j;
+ if (reg_renumber[allocno[allocno_order[i]].reg] >= 0)
+ continue;
+ fprintf (file, " %d", allocno[allocno_order[i]].reg);
+ for (j = 0; j < max_regno; j++)
+ if (reg_allocno[j] == allocno_order[i]
+ && j != allocno[allocno_order[i]].reg)
+ fprintf (file, "+%d", j);
+ if (allocno[allocno_order[i]].size != 1)
+ fprintf (file, " (%d)", allocno[allocno_order[i]].size);
+ }
fprintf (file, "\n");
- for (i = 0; i < max_allocno; i++)
- {
- int j;
- fprintf (file, ";; %d conflicts:", allocno[i].reg);
- for (j = 0; j < max_allocno; j++)
- if (CONFLICTP (j, i))
- fprintf (file, " %d", allocno[j].reg);
- for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
- if (TEST_HARD_REG_BIT (allocno[i].hard_reg_conflicts, j))
- fprintf (file, " %d", j);
- fprintf (file, "\n");
-
- has_preferences = 0;
- for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
- if (TEST_HARD_REG_BIT (allocno[i].hard_reg_preferences, j))
- has_preferences = 1;
-
- if (! has_preferences)
- continue;
- fprintf (file, ";; %d preferences:", allocno[i].reg);
- for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
- if (TEST_HARD_REG_BIT (allocno[i].hard_reg_preferences, j))
- fprintf (file, " %d", j);
- fprintf (file, "\n");
- }
+ for (regno = 0; regno < max_regno; regno++)
+ if ((i = reg_allocno[regno]) >= 0)
+ {
+ int j;
+ adjacency_iter ai;
+ fprintf (file, ";; %d conflicts:", allocno[i].reg);
+ FOR_EACH_CONFLICT (i, j, ai)
+ {
+ fprintf (file, " %d", allocno[j].reg);
+ }
+ for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
+ if (TEST_HARD_REG_BIT (allocno[i].hard_reg_conflicts, j)
+ && !fixed_regs[j])
+ fprintf (file, " %d", j);
+ fprintf (file, "\n");
+
+ has_preferences = 0;
+ for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
+ if (TEST_HARD_REG_BIT (allocno[i].hard_reg_preferences, j))
+ has_preferences = 1;
+
+ if (!has_preferences)
+ continue;
+ fprintf (file, ";; %d preferences:", allocno[i].reg);
+ for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
+ if (TEST_HARD_REG_BIT (allocno[i].hard_reg_preferences, j))
+ fprintf (file, " %d", j);
+ fprintf (file, "\n");
+ }
fprintf (file, "\n");
}
void
-dump_global_regs (file)
- FILE *file;
+dump_global_regs (FILE *file)
{
int i, j;
fprintf (file, "\n\n;; Hard regs used: ");
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (regs_ever_live[i])
+ if (df_regs_ever_live_p (i))
fprintf (file, " %d", i);
fprintf (file, "\n\n");
}
+
+/* Run old register allocator. Return TRUE if we must exit
+ rest_of_compilation upon return. */
+static unsigned int
+rest_of_handle_global_alloc (void)
+{
+ bool failure;
+
+ /* If optimizing, allocate remaining pseudo-regs. Do the reload
+ pass fixing up any insns that are invalid. */
+ if (optimize && dbg_cnt (global_alloc_at_func))
+ failure = global_alloc ();
+ else
+ {
+ /* There is just too much going on in the register allocators to
+ keep things up to date. At the end we have to rescan anyway
+ because things change when the reload_completed flag is set.
+ So we just turn off scanning and we will rescan by hand. */
+ df_set_flags (DF_NO_INSN_RESCAN);
+ compute_regsets (&eliminable_regset, &no_global_alloc_regs);
+ build_insn_chain ();
+ df_set_flags (DF_NO_INSN_RESCAN);
+ failure = reload (get_insns (), 0);
+ }
+
+ if (dump_enabled_p (pass_global_alloc.pass.static_pass_number))
+ {
+ timevar_push (TV_DUMP);
+ dump_global_regs (dump_file);
+ timevar_pop (TV_DUMP);
+ }
+
+ /* FIXME: This appears on the surface to be wrong thing to be doing.
+ So much of the compiler is designed to check reload_completed to
+ see if it is running after reload that seems doomed to failure.
+ We should be returning a value that says that we have found
+ errors so that nothing but the cleanup passes are run
+ afterwards. */
+ gcc_assert (reload_completed || failure);
+ reload_completed = !failure;
+
+ /* The world has changed so much that at this point we might as well
+ just rescan everything. Note that df_rescan_all_insns is not
+ going to help here because it does not touch the artificial uses
+ and defs. */
+ df_finish_pass (true);
+ if (optimize > 1)
+ df_live_add_problem ();
+ df_scan_alloc (NULL);
+ df_scan_blocks ();
+
+ if (optimize)
+ df_analyze ();
+
+ regstat_free_n_sets_and_refs ();
+ regstat_free_ri ();
+ return 0;
+}
+
+struct rtl_opt_pass pass_global_alloc =
+{
+ {
+ RTL_PASS,
+ "greg", /* name */
+ NULL, /* gate */
+ rest_of_handle_global_alloc, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_GLOBAL_ALLOC, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func | TODO_verify_rtl_sharing
+ | TODO_ggc_collect /* todo_flags_finish */
+ }
+};
+
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