aboutsummaryrefslogtreecommitdiffstats
path: root/gcc-4.2.1/gcc/caller-save.c
diff options
context:
space:
mode:
Diffstat (limited to 'gcc-4.2.1/gcc/caller-save.c')
-rw-r--r--gcc-4.2.1/gcc/caller-save.c863
1 files changed, 0 insertions, 863 deletions
diff --git a/gcc-4.2.1/gcc/caller-save.c b/gcc-4.2.1/gcc/caller-save.c
deleted file mode 100644
index c81c72c49..000000000
--- a/gcc-4.2.1/gcc/caller-save.c
+++ /dev/null
@@ -1,863 +0,0 @@
-/* Save and restore call-clobbered registers which are live across a call.
- Copyright (C) 1989, 1992, 1994, 1995, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005 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
-version.
-
-GCC is distributed in the hope that it will be useful, but WITHOUT ANY
-WARRANTY; without even the implied warranty of MERCHANTABILITY or
-FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
-for more details.
-
-You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301, USA. */
-
-#include "config.h"
-#include "system.h"
-#include "coretypes.h"
-#include "tm.h"
-#include "rtl.h"
-#include "regs.h"
-#include "insn-config.h"
-#include "flags.h"
-#include "hard-reg-set.h"
-#include "recog.h"
-#include "basic-block.h"
-#include "reload.h"
-#include "function.h"
-#include "expr.h"
-#include "toplev.h"
-#include "tm_p.h"
-#include "addresses.h"
-
-#ifndef MAX_MOVE_MAX
-#define MAX_MOVE_MAX MOVE_MAX
-#endif
-
-#ifndef MIN_UNITS_PER_WORD
-#define MIN_UNITS_PER_WORD UNITS_PER_WORD
-#endif
-
-#define MOVE_MAX_WORDS (MOVE_MAX / UNITS_PER_WORD)
-
-/* Modes for each hard register that we can save. The smallest mode is wide
- enough to save the entire contents of the register. When saving the
- register because it is live we first try to save in multi-register modes.
- If that is not possible the save is done one register at a time. */
-
-static enum machine_mode
- regno_save_mode[FIRST_PSEUDO_REGISTER][MAX_MOVE_MAX / MIN_UNITS_PER_WORD + 1];
-
-/* For each hard register, a place on the stack where it can be saved,
- if needed. */
-
-static rtx
- regno_save_mem[FIRST_PSEUDO_REGISTER][MAX_MOVE_MAX / MIN_UNITS_PER_WORD + 1];
-
-/* We will only make a register eligible for caller-save if it can be
- saved in its widest mode with a simple SET insn as long as the memory
- address is valid. We record the INSN_CODE is those insns here since
- when we emit them, the addresses might not be valid, so they might not
- be recognized. */
-
-static int
- reg_save_code[FIRST_PSEUDO_REGISTER][MAX_MACHINE_MODE];
-static int
- reg_restore_code[FIRST_PSEUDO_REGISTER][MAX_MACHINE_MODE];
-
-/* Set of hard regs currently residing in save area (during insn scan). */
-
-static HARD_REG_SET hard_regs_saved;
-
-/* Number of registers currently in hard_regs_saved. */
-
-static int n_regs_saved;
-
-/* Computed by mark_referenced_regs, all regs referenced in a given
- insn. */
-static HARD_REG_SET referenced_regs;
-
-
-static void mark_set_regs (rtx, rtx, void *);
-static void mark_referenced_regs (rtx);
-static int insert_save (struct insn_chain *, int, int, HARD_REG_SET *,
- enum machine_mode *);
-static int insert_restore (struct insn_chain *, int, int, int,
- enum machine_mode *);
-static struct insn_chain *insert_one_insn (struct insn_chain *, int, int,
- rtx);
-static void add_stored_regs (rtx, rtx, void *);
-
-/* Initialize for caller-save.
-
- Look at all the hard registers that are used by a call and for which
- regclass.c has not already excluded from being used across a call.
-
- Ensure that we can find a mode to save the register and that there is a
- simple insn to save and restore the register. This latter check avoids
- problems that would occur if we tried to save the MQ register of some
- machines directly into memory. */
-
-void
-init_caller_save (void)
-{
- rtx addr_reg;
- int offset;
- rtx address;
- int i, j;
- enum machine_mode mode;
- rtx savepat, restpat;
- rtx test_reg, test_mem;
- rtx saveinsn, restinsn;
-
- /* First find all the registers that we need to deal with and all
- the modes that they can have. If we can't find a mode to use,
- we can't have the register live over calls. */
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- {
- if (call_used_regs[i] && ! call_fixed_regs[i])
- {
- for (j = 1; j <= MOVE_MAX_WORDS; j++)
- {
- regno_save_mode[i][j] = HARD_REGNO_CALLER_SAVE_MODE (i, j,
- VOIDmode);
- if (regno_save_mode[i][j] == VOIDmode && j == 1)
- {
- call_fixed_regs[i] = 1;
- SET_HARD_REG_BIT (call_fixed_reg_set, i);
- }
- }
- }
- else
- regno_save_mode[i][1] = VOIDmode;
- }
-
- /* The following code tries to approximate the conditions under which
- we can easily save and restore a register without scratch registers or
- other complexities. It will usually work, except under conditions where
- the validity of an insn operand is dependent on the address offset.
- No such cases are currently known.
-
- We first find a typical offset from some BASE_REG_CLASS register.
- This address is chosen by finding the first register in the class
- and by finding the smallest power of two that is a valid offset from
- that register in every mode we will use to save registers. */
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (TEST_HARD_REG_BIT
- (reg_class_contents
- [(int) base_reg_class (regno_save_mode [i][1], PLUS, CONST_INT)], i))
- break;
-
- gcc_assert (i < FIRST_PSEUDO_REGISTER);
-
- addr_reg = gen_rtx_REG (Pmode, i);
-
- for (offset = 1 << (HOST_BITS_PER_INT / 2); offset; offset >>= 1)
- {
- address = gen_rtx_PLUS (Pmode, addr_reg, GEN_INT (offset));
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (regno_save_mode[i][1] != VOIDmode
- && ! strict_memory_address_p (regno_save_mode[i][1], address))
- break;
-
- if (i == FIRST_PSEUDO_REGISTER)
- break;
- }
-
- /* If we didn't find a valid address, we must use register indirect. */
- if (offset == 0)
- address = addr_reg;
-
- /* Next we try to form an insn to save and restore the register. We
- see if such an insn is recognized and meets its constraints.
-
- To avoid lots of unnecessary RTL allocation, we construct all the RTL
- once, then modify the memory and register operands in-place. */
-
- test_reg = gen_rtx_REG (VOIDmode, 0);
- test_mem = gen_rtx_MEM (VOIDmode, address);
- savepat = gen_rtx_SET (VOIDmode, test_mem, test_reg);
- restpat = gen_rtx_SET (VOIDmode, test_reg, test_mem);
-
- saveinsn = gen_rtx_INSN (VOIDmode, 0, 0, 0, 0, 0, savepat, -1, 0, 0);
- restinsn = gen_rtx_INSN (VOIDmode, 0, 0, 0, 0, 0, restpat, -1, 0, 0);
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- for (mode = 0 ; mode < MAX_MACHINE_MODE; mode++)
- if (HARD_REGNO_MODE_OK (i, mode))
- {
- int ok;
-
- /* Update the register number and modes of the register
- and memory operand. */
- REGNO (test_reg) = i;
- PUT_MODE (test_reg, mode);
- PUT_MODE (test_mem, mode);
-
- /* Force re-recognition of the modified insns. */
- INSN_CODE (saveinsn) = -1;
- INSN_CODE (restinsn) = -1;
-
- reg_save_code[i][mode] = recog_memoized (saveinsn);
- reg_restore_code[i][mode] = recog_memoized (restinsn);
-
- /* Now extract both insns and see if we can meet their
- constraints. */
- ok = (reg_save_code[i][mode] != -1
- && reg_restore_code[i][mode] != -1);
- if (ok)
- {
- extract_insn (saveinsn);
- ok = constrain_operands (1);
- extract_insn (restinsn);
- ok &= constrain_operands (1);
- }
-
- if (! ok)
- {
- reg_save_code[i][mode] = -1;
- reg_restore_code[i][mode] = -1;
- }
- }
- else
- {
- reg_save_code[i][mode] = -1;
- reg_restore_code[i][mode] = -1;
- }
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- for (j = 1; j <= MOVE_MAX_WORDS; j++)
- if (reg_save_code [i][regno_save_mode[i][j]] == -1)
- {
- regno_save_mode[i][j] = VOIDmode;
- if (j == 1)
- {
- call_fixed_regs[i] = 1;
- SET_HARD_REG_BIT (call_fixed_reg_set, i);
- }
- }
-}
-
-/* Initialize save areas by showing that we haven't allocated any yet. */
-
-void
-init_save_areas (void)
-{
- int i, j;
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- for (j = 1; j <= MOVE_MAX_WORDS; j++)
- regno_save_mem[i][j] = 0;
-}
-
-/* Allocate save areas for any hard registers that might need saving.
- We take a conservative approach here and look for call-clobbered hard
- registers that are assigned to pseudos that cross calls. This may
- overestimate slightly (especially if some of these registers are later
- used as spill registers), but it should not be significant.
-
- Future work:
-
- In the fallback case we should iterate backwards across all possible
- modes for the save, choosing the largest available one instead of
- falling back to the smallest mode immediately. (eg TF -> DF -> SF).
-
- We do not try to use "move multiple" instructions that exist
- on some machines (such as the 68k moveml). It could be a win to try
- and use them when possible. The hard part is doing it in a way that is
- machine independent since they might be saving non-consecutive
- registers. (imagine caller-saving d0,d1,a0,a1 on the 68k) */
-
-void
-setup_save_areas (void)
-{
- int i, j, k;
- unsigned int r;
- HARD_REG_SET hard_regs_used;
-
- /* Allocate space in the save area for the largest multi-register
- pseudos first, then work backwards to single register
- pseudos. */
-
- /* Find and record all call-used hard-registers in this function. */
- CLEAR_HARD_REG_SET (hard_regs_used);
- for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
- if (reg_renumber[i] >= 0 && REG_N_CALLS_CROSSED (i) > 0)
- {
- unsigned int regno = reg_renumber[i];
- unsigned int endregno
- = regno + hard_regno_nregs[regno][GET_MODE (regno_reg_rtx[i])];
-
- for (r = regno; r < endregno; r++)
- if (call_used_regs[r])
- SET_HARD_REG_BIT (hard_regs_used, r);
- }
-
- /* Now run through all the call-used hard-registers and allocate
- space for them in the caller-save area. Try to allocate space
- in a manner which allows multi-register saves/restores to be done. */
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- for (j = MOVE_MAX_WORDS; j > 0; j--)
- {
- int do_save = 1;
-
- /* If no mode exists for this size, try another. Also break out
- if we have already saved this hard register. */
- if (regno_save_mode[i][j] == VOIDmode || regno_save_mem[i][1] != 0)
- continue;
-
- /* See if any register in this group has been saved. */
- for (k = 0; k < j; k++)
- if (regno_save_mem[i + k][1])
- {
- do_save = 0;
- break;
- }
- if (! do_save)
- continue;
-
- for (k = 0; k < j; k++)
- if (! TEST_HARD_REG_BIT (hard_regs_used, i + k))
- {
- do_save = 0;
- break;
- }
- if (! do_save)
- continue;
-
- /* We have found an acceptable mode to store in. */
- regno_save_mem[i][j]
- = assign_stack_local (regno_save_mode[i][j],
- GET_MODE_SIZE (regno_save_mode[i][j]), 0);
-
- /* Setup single word save area just in case... */
- for (k = 0; k < j; k++)
- /* This should not depend on WORDS_BIG_ENDIAN.
- The order of words in regs is the same as in memory. */
- regno_save_mem[i + k][1]
- = adjust_address_nv (regno_save_mem[i][j],
- regno_save_mode[i + k][1],
- k * UNITS_PER_WORD);
- }
-
- /* Now loop again and set the alias set of any save areas we made to
- the alias set used to represent frame objects. */
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- for (j = MOVE_MAX_WORDS; j > 0; j--)
- if (regno_save_mem[i][j] != 0)
- set_mem_alias_set (regno_save_mem[i][j], get_frame_alias_set ());
-}
-
-/* Find the places where hard regs are live across calls and save them. */
-
-void
-save_call_clobbered_regs (void)
-{
- struct insn_chain *chain, *next;
- enum machine_mode save_mode [FIRST_PSEUDO_REGISTER];
-
- /* Computed in mark_set_regs, holds all registers set by the current
- instruction. */
- HARD_REG_SET this_insn_sets;
-
- CLEAR_HARD_REG_SET (hard_regs_saved);
- n_regs_saved = 0;
-
- for (chain = reload_insn_chain; chain != 0; chain = next)
- {
- rtx insn = chain->insn;
- enum rtx_code code = GET_CODE (insn);
-
- next = chain->next;
-
- gcc_assert (!chain->is_caller_save_insn);
-
- if (INSN_P (insn))
- {
- /* If some registers have been saved, see if INSN references
- any of them. We must restore them before the insn if so. */
-
- if (n_regs_saved)
- {
- int regno;
-
- if (code == JUMP_INSN)
- /* Restore all registers if this is a JUMP_INSN. */
- COPY_HARD_REG_SET (referenced_regs, hard_regs_saved);
- else
- {
- CLEAR_HARD_REG_SET (referenced_regs);
- mark_referenced_regs (PATTERN (insn));
- AND_HARD_REG_SET (referenced_regs, hard_regs_saved);
- }
-
- for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
- if (TEST_HARD_REG_BIT (referenced_regs, regno))
- regno += insert_restore (chain, 1, regno, MOVE_MAX_WORDS, save_mode);
- }
-
- if (code == CALL_INSN && ! find_reg_note (insn, REG_NORETURN, NULL))
- {
- unsigned regno;
- HARD_REG_SET hard_regs_to_save;
- reg_set_iterator rsi;
-
- /* Use the register life information in CHAIN to compute which
- regs are live during the call. */
- REG_SET_TO_HARD_REG_SET (hard_regs_to_save,
- &chain->live_throughout);
- /* Save hard registers always in the widest mode available. */
- for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
- if (TEST_HARD_REG_BIT (hard_regs_to_save, regno))
- save_mode [regno] = regno_save_mode [regno][1];
- else
- save_mode [regno] = VOIDmode;
-
- /* Look through all live pseudos, mark their hard registers
- and choose proper mode for saving. */
- EXECUTE_IF_SET_IN_REG_SET
- (&chain->live_throughout, FIRST_PSEUDO_REGISTER, regno, rsi)
- {
- int r = reg_renumber[regno];
- int nregs;
- enum machine_mode mode;
-
- gcc_assert (r >= 0);
- nregs = hard_regno_nregs[r][PSEUDO_REGNO_MODE (regno)];
- mode = HARD_REGNO_CALLER_SAVE_MODE
- (r, nregs, PSEUDO_REGNO_MODE (regno));
- if (GET_MODE_BITSIZE (mode)
- > GET_MODE_BITSIZE (save_mode[r]))
- save_mode[r] = mode;
- while (nregs-- > 0)
- SET_HARD_REG_BIT (hard_regs_to_save, r + nregs);
- }
-
- /* Record all registers set in this call insn. These don't need
- to be saved. N.B. the call insn might set a subreg of a
- multi-hard-reg pseudo; then the pseudo is considered live
- during the call, but the subreg that is set isn't. */
- CLEAR_HARD_REG_SET (this_insn_sets);
- note_stores (PATTERN (insn), mark_set_regs, &this_insn_sets);
- /* Sibcalls are considered to set the return value,
- compare flow.c:propagate_one_insn. */
- if (SIBLING_CALL_P (insn) && current_function_return_rtx)
- mark_set_regs (current_function_return_rtx, NULL_RTX,
- &this_insn_sets);
-
- /* Compute which hard regs must be saved before this call. */
- AND_COMPL_HARD_REG_SET (hard_regs_to_save, call_fixed_reg_set);
- AND_COMPL_HARD_REG_SET (hard_regs_to_save, this_insn_sets);
- AND_COMPL_HARD_REG_SET (hard_regs_to_save, hard_regs_saved);
- AND_HARD_REG_SET (hard_regs_to_save, call_used_reg_set);
-
- for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
- if (TEST_HARD_REG_BIT (hard_regs_to_save, regno))
- regno += insert_save (chain, 1, regno, &hard_regs_to_save, save_mode);
-
- /* Must recompute n_regs_saved. */
- n_regs_saved = 0;
- for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
- if (TEST_HARD_REG_BIT (hard_regs_saved, regno))
- n_regs_saved++;
- }
- }
-
- if (chain->next == 0 || chain->next->block > chain->block)
- {
- int regno;
- /* At the end of the basic block, we must restore any registers that
- remain saved. If the last insn in the block is a JUMP_INSN, put
- the restore before the insn, otherwise, put it after the insn. */
-
- if (n_regs_saved)
- for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
- if (TEST_HARD_REG_BIT (hard_regs_saved, regno))
- regno += insert_restore (chain, JUMP_P (insn),
- regno, MOVE_MAX_WORDS, save_mode);
- }
- }
-}
-
-/* Here from note_stores, or directly from save_call_clobbered_regs, when
- an insn stores a value in a register.
- Set the proper bit or bits in this_insn_sets. All pseudos that have
- been assigned hard regs have had their register number changed already,
- so we can ignore pseudos. */
-static void
-mark_set_regs (rtx reg, rtx setter ATTRIBUTE_UNUSED, void *data)
-{
- int regno, endregno, i;
- enum machine_mode mode = GET_MODE (reg);
- HARD_REG_SET *this_insn_sets = data;
-
- if (GET_CODE (reg) == SUBREG)
- {
- rtx inner = SUBREG_REG (reg);
- if (!REG_P (inner) || REGNO (inner) >= FIRST_PSEUDO_REGISTER)
- return;
- regno = subreg_regno (reg);
- }
- else if (REG_P (reg)
- && REGNO (reg) < FIRST_PSEUDO_REGISTER)
- regno = REGNO (reg);
- else
- return;
-
- endregno = regno + hard_regno_nregs[regno][mode];
-
- for (i = regno; i < endregno; i++)
- SET_HARD_REG_BIT (*this_insn_sets, i);
-}
-
-/* Here from note_stores when an insn stores a value in a register.
- Set the proper bit or bits in the passed regset. All pseudos that have
- been assigned hard regs have had their register number changed already,
- so we can ignore pseudos. */
-static void
-add_stored_regs (rtx reg, rtx setter, void *data)
-{
- int regno, endregno, i;
- enum machine_mode mode = GET_MODE (reg);
- int offset = 0;
-
- if (GET_CODE (setter) == CLOBBER)
- return;
-
- if (GET_CODE (reg) == SUBREG && REG_P (SUBREG_REG (reg)))
- {
- offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
- GET_MODE (SUBREG_REG (reg)),
- SUBREG_BYTE (reg),
- GET_MODE (reg));
- reg = SUBREG_REG (reg);
- }
-
- if (!REG_P (reg) || REGNO (reg) >= FIRST_PSEUDO_REGISTER)
- return;
-
- regno = REGNO (reg) + offset;
- endregno = regno + hard_regno_nregs[regno][mode];
-
- for (i = regno; i < endregno; i++)
- SET_REGNO_REG_SET ((regset) data, i);
-}
-
-/* Walk X and record all referenced registers in REFERENCED_REGS. */
-static void
-mark_referenced_regs (rtx x)
-{
- enum rtx_code code = GET_CODE (x);
- const char *fmt;
- int i, j;
-
- if (code == SET)
- mark_referenced_regs (SET_SRC (x));
- if (code == SET || code == CLOBBER)
- {
- x = SET_DEST (x);
- code = GET_CODE (x);
- if ((code == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
- || code == PC || code == CC0
- || (code == SUBREG && REG_P (SUBREG_REG (x))
- && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER
- /* If we're setting only part of a multi-word register,
- we shall mark it as referenced, because the words
- that are not being set should be restored. */
- && ((GET_MODE_SIZE (GET_MODE (x))
- >= GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
- || (GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
- <= UNITS_PER_WORD))))
- return;
- }
- if (code == MEM || code == SUBREG)
- {
- x = XEXP (x, 0);
- code = GET_CODE (x);
- }
-
- if (code == REG)
- {
- int regno = REGNO (x);
- int hardregno = (regno < FIRST_PSEUDO_REGISTER ? regno
- : reg_renumber[regno]);
-
- if (hardregno >= 0)
- {
- int nregs = hard_regno_nregs[hardregno][GET_MODE (x)];
- while (nregs-- > 0)
- SET_HARD_REG_BIT (referenced_regs, hardregno + nregs);
- }
- /* If this is a pseudo that did not get a hard register, scan its
- memory location, since it might involve the use of another
- register, which might be saved. */
- else if (reg_equiv_mem[regno] != 0)
- mark_referenced_regs (XEXP (reg_equiv_mem[regno], 0));
- else if (reg_equiv_address[regno] != 0)
- mark_referenced_regs (reg_equiv_address[regno]);
- return;
- }
-
- fmt = GET_RTX_FORMAT (code);
- for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
- {
- if (fmt[i] == 'e')
- mark_referenced_regs (XEXP (x, i));
- else if (fmt[i] == 'E')
- for (j = XVECLEN (x, i) - 1; j >= 0; j--)
- mark_referenced_regs (XVECEXP (x, i, j));
- }
-}
-
-/* Insert a sequence of insns to restore. Place these insns in front of
- CHAIN if BEFORE_P is nonzero, behind the insn otherwise. MAXRESTORE is
- the maximum number of registers which should be restored during this call.
- It should never be less than 1 since we only work with entire registers.
-
- Note that we have verified in init_caller_save that we can do this
- with a simple SET, so use it. Set INSN_CODE to what we save there
- since the address might not be valid so the insn might not be recognized.
- These insns will be reloaded and have register elimination done by
- find_reload, so we need not worry about that here.
-
- Return the extra number of registers saved. */
-
-static int
-insert_restore (struct insn_chain *chain, int before_p, int regno,
- int maxrestore, enum machine_mode *save_mode)
-{
- int i, k;
- rtx pat = NULL_RTX;
- int code;
- unsigned int numregs = 0;
- struct insn_chain *new;
- rtx mem;
-
- /* A common failure mode if register status is not correct in the
- RTL is for this routine to be called with a REGNO we didn't
- expect to save. That will cause us to write an insn with a (nil)
- SET_DEST or SET_SRC. Instead of doing so and causing a crash
- later, check for this common case here instead. This will remove
- one step in debugging such problems. */
- gcc_assert (regno_save_mem[regno][1]);
-
- /* Get the pattern to emit and update our status.
-
- See if we can restore `maxrestore' registers at once. Work
- backwards to the single register case. */
- for (i = maxrestore; i > 0; i--)
- {
- int j;
- int ok = 1;
-
- if (regno_save_mem[regno][i] == 0)
- continue;
-
- for (j = 0; j < i; j++)
- if (! TEST_HARD_REG_BIT (hard_regs_saved, regno + j))
- {
- ok = 0;
- break;
- }
- /* Must do this one restore at a time. */
- if (! ok)
- continue;
-
- numregs = i;
- break;
- }
-
- mem = regno_save_mem [regno][numregs];
- if (save_mode [regno] != VOIDmode
- && save_mode [regno] != GET_MODE (mem)
- && numregs == (unsigned int) hard_regno_nregs[regno][save_mode [regno]])
- mem = adjust_address (mem, save_mode[regno], 0);
- else
- mem = copy_rtx (mem);
- pat = gen_rtx_SET (VOIDmode,
- gen_rtx_REG (GET_MODE (mem),
- regno), mem);
- code = reg_restore_code[regno][GET_MODE (mem)];
- new = insert_one_insn (chain, before_p, code, pat);
-
- /* Clear status for all registers we restored. */
- for (k = 0; k < i; k++)
- {
- CLEAR_HARD_REG_BIT (hard_regs_saved, regno + k);
- SET_REGNO_REG_SET (&new->dead_or_set, regno + k);
- n_regs_saved--;
- }
-
- /* Tell our callers how many extra registers we saved/restored. */
- return numregs - 1;
-}
-
-/* Like insert_restore above, but save registers instead. */
-
-static int
-insert_save (struct insn_chain *chain, int before_p, int regno,
- HARD_REG_SET (*to_save), enum machine_mode *save_mode)
-{
- int i;
- unsigned int k;
- rtx pat = NULL_RTX;
- int code;
- unsigned int numregs = 0;
- struct insn_chain *new;
- rtx mem;
-
- /* A common failure mode if register status is not correct in the
- RTL is for this routine to be called with a REGNO we didn't
- expect to save. That will cause us to write an insn with a (nil)
- SET_DEST or SET_SRC. Instead of doing so and causing a crash
- later, check for this common case here. This will remove one
- step in debugging such problems. */
- gcc_assert (regno_save_mem[regno][1]);
-
- /* Get the pattern to emit and update our status.
-
- See if we can save several registers with a single instruction.
- Work backwards to the single register case. */
- for (i = MOVE_MAX_WORDS; i > 0; i--)
- {
- int j;
- int ok = 1;
- if (regno_save_mem[regno][i] == 0)
- continue;
-
- for (j = 0; j < i; j++)
- if (! TEST_HARD_REG_BIT (*to_save, regno + j))
- {
- ok = 0;
- break;
- }
- /* Must do this one save at a time. */
- if (! ok)
- continue;
-
- numregs = i;
- break;
- }
-
- mem = regno_save_mem [regno][numregs];
- if (save_mode [regno] != VOIDmode
- && save_mode [regno] != GET_MODE (mem)
- && numregs == (unsigned int) hard_regno_nregs[regno][save_mode [regno]])
- mem = adjust_address (mem, save_mode[regno], 0);
- else
- mem = copy_rtx (mem);
- pat = gen_rtx_SET (VOIDmode, mem,
- gen_rtx_REG (GET_MODE (mem),
- regno));
- code = reg_save_code[regno][GET_MODE (mem)];
- new = insert_one_insn (chain, before_p, code, pat);
-
- /* Set hard_regs_saved and dead_or_set for all the registers we saved. */
- for (k = 0; k < numregs; k++)
- {
- SET_HARD_REG_BIT (hard_regs_saved, regno + k);
- SET_REGNO_REG_SET (&new->dead_or_set, regno + k);
- n_regs_saved++;
- }
-
- /* Tell our callers how many extra registers we saved/restored. */
- return numregs - 1;
-}
-
-/* Emit a new caller-save insn and set the code. */
-static struct insn_chain *
-insert_one_insn (struct insn_chain *chain, int before_p, int code, rtx pat)
-{
- rtx insn = chain->insn;
- struct insn_chain *new;
-
-#ifdef HAVE_cc0
- /* If INSN references CC0, put our insns in front of the insn that sets
- CC0. This is always safe, since the only way we could be passed an
- insn that references CC0 is for a restore, and doing a restore earlier
- isn't a problem. We do, however, assume here that CALL_INSNs don't
- reference CC0. Guard against non-INSN's like CODE_LABEL. */
-
- if ((NONJUMP_INSN_P (insn) || JUMP_P (insn))
- && before_p
- && reg_referenced_p (cc0_rtx, PATTERN (insn)))
- chain = chain->prev, insn = chain->insn;
-#endif
-
- new = new_insn_chain ();
- if (before_p)
- {
- rtx link;
-
- new->prev = chain->prev;
- if (new->prev != 0)
- new->prev->next = new;
- else
- reload_insn_chain = new;
-
- chain->prev = new;
- new->next = chain;
- new->insn = emit_insn_before (pat, insn);
- /* ??? It would be nice if we could exclude the already / still saved
- registers from the live sets. */
- COPY_REG_SET (&new->live_throughout, &chain->live_throughout);
- /* Registers that die in CHAIN->INSN still live in the new insn. */
- for (link = REG_NOTES (chain->insn); link; link = XEXP (link, 1))
- {
- if (REG_NOTE_KIND (link) == REG_DEAD)
- {
- rtx reg = XEXP (link, 0);
- int regno, i;
-
- gcc_assert (REG_P (reg));
- regno = REGNO (reg);
- if (regno >= FIRST_PSEUDO_REGISTER)
- regno = reg_renumber[regno];
- if (regno < 0)
- continue;
- for (i = hard_regno_nregs[regno][GET_MODE (reg)] - 1;
- i >= 0; i--)
- SET_REGNO_REG_SET (&new->live_throughout, regno + i);
- }
- }
- CLEAR_REG_SET (&new->dead_or_set);
- if (chain->insn == BB_HEAD (BASIC_BLOCK (chain->block)))
- BB_HEAD (BASIC_BLOCK (chain->block)) = new->insn;
- }
- else
- {
- new->next = chain->next;
- if (new->next != 0)
- new->next->prev = new;
- chain->next = new;
- new->prev = chain;
- new->insn = emit_insn_after (pat, insn);
- /* ??? It would be nice if we could exclude the already / still saved
- registers from the live sets, and observe REG_UNUSED notes. */
- COPY_REG_SET (&new->live_throughout, &chain->live_throughout);
- /* Registers that are set in CHAIN->INSN live in the new insn.
- (Unless there is a REG_UNUSED note for them, but we don't
- look for them here.) */
- note_stores (PATTERN (chain->insn), add_stored_regs,
- &new->live_throughout);
- CLEAR_REG_SET (&new->dead_or_set);
- if (chain->insn == BB_END (BASIC_BLOCK (chain->block)))
- BB_END (BASIC_BLOCK (chain->block)) = new->insn;
- }
- new->block = chain->block;
- new->is_caller_save_insn = 1;
-
- INSN_CODE (new->insn) = code;
- return new;
-}