/* 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, 2006, 2007, 2008, 2009, 2010
+ 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
Free Software Foundation, Inc.
This file is part of GCC.
#include "function.h"
#include "expr.h"
#include "diagnostic-core.h"
-#include "toplev.h"
#include "tm_p.h"
#include "addresses.h"
#include "output.h"
if (cached_reg_save_code[reg][mode])
return cached_reg_save_code[reg][mode];
if (!HARD_REGNO_MODE_OK (reg, mode))
- {
- cached_reg_save_code[reg][mode] = -1;
- cached_reg_restore_code[reg][mode] = -1;
- return -1;
- }
+ {
+ /* Depending on how HARD_REGNO_MODE_OK is defined, range propagation
+ might deduce here that reg >= FIRST_PSEUDO_REGISTER. So the assert
+ below silences a warning. */
+ gcc_assert (reg < FIRST_PSEUDO_REGISTER);
+ cached_reg_save_code[reg][mode] = -1;
+ cached_reg_restore_code[reg][mode] = -1;
+ return -1;
+ }
/* Update the register number and modes of the register
and memory operand. */
void
setup_save_areas (void)
{
- int i, j, k;
- unsigned int r;
+ int i, j, k, freq;
HARD_REG_SET hard_regs_used;
+ struct saved_hard_reg *saved_reg;
+ rtx insn;
+ struct insn_chain *chain, *next;
+ unsigned int regno;
+ HARD_REG_SET hard_regs_to_save, used_regs, this_insn_sets;
+ reg_set_iterator rsi;
- /* 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
- = end_hard_regno (GET_MODE (regno_reg_rtx[i]), regno);
- for (r = regno; r < endregno; r++)
- if (call_used_regs[r])
- SET_HARD_REG_BIT (hard_regs_used, r);
- }
- if (optimize && flag_ira_share_save_slots)
+ /* Find every CALL_INSN and record which hard regs are live across the
+ call into HARD_REG_MAP and HARD_REGS_USED. */
+ initiate_saved_hard_regs ();
+ /* Create hard reg saved regs. */
+ for (chain = reload_insn_chain; chain != 0; chain = next)
{
- rtx insn, slot;
- struct insn_chain *chain, *next;
- char *saved_reg_conflicts;
- unsigned int regno;
- int next_k, freq;
- struct saved_hard_reg *saved_reg, *saved_reg2, *saved_reg3;
- int call_saved_regs_num;
- struct saved_hard_reg *call_saved_regs[FIRST_PSEUDO_REGISTER];
- HARD_REG_SET hard_regs_to_save, used_regs, this_insn_sets;
- reg_set_iterator rsi;
- int best_slot_num;
- int prev_save_slots_num;
- rtx prev_save_slots[FIRST_PSEUDO_REGISTER];
-
- initiate_saved_hard_regs ();
- /* Create hard reg saved regs. */
- for (chain = reload_insn_chain; chain != 0; chain = next)
+ insn = chain->insn;
+ next = chain->next;
+ if (!CALL_P (insn)
+ || find_reg_note (insn, REG_NORETURN, NULL))
+ continue;
+ freq = REG_FREQ_FROM_BB (BLOCK_FOR_INSN (insn));
+ REG_SET_TO_HARD_REG_SET (hard_regs_to_save,
+ &chain->live_throughout);
+ COPY_HARD_REG_SET (used_regs, call_used_reg_set);
+
+ /* 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. */
+ if (SIBLING_CALL_P (insn) && crtl->return_rtx)
+ mark_set_regs (crtl->return_rtx, NULL_RTX, &this_insn_sets);
+
+ AND_COMPL_HARD_REG_SET (used_regs, call_fixed_reg_set);
+ AND_COMPL_HARD_REG_SET (used_regs, this_insn_sets);
+ AND_HARD_REG_SET (hard_regs_to_save, used_regs);
+ for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
+ if (TEST_HARD_REG_BIT (hard_regs_to_save, regno))
+ {
+ if (hard_reg_map[regno] != NULL)
+ hard_reg_map[regno]->call_freq += freq;
+ else
+ saved_reg = new_saved_hard_reg (regno, freq);
+ SET_HARD_REG_BIT (hard_regs_used, regno);
+ }
+ /* Look through all live pseudos, mark their hard registers. */
+ EXECUTE_IF_SET_IN_REG_SET
+ (&chain->live_throughout, FIRST_PSEUDO_REGISTER, regno, rsi)
{
- insn = chain->insn;
- next = chain->next;
- if (!CALL_P (insn)
- || find_reg_note (insn, REG_NORETURN, NULL))
- continue;
- freq = REG_FREQ_FROM_BB (BLOCK_FOR_INSN (insn));
- REG_SET_TO_HARD_REG_SET (hard_regs_to_save,
- &chain->live_throughout);
- COPY_HARD_REG_SET (used_regs, call_used_reg_set);
+ int r = reg_renumber[regno];
+ int bound;
- /* 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. */
- if (SIBLING_CALL_P (insn) && crtl->return_rtx)
- mark_set_regs (crtl->return_rtx, NULL_RTX, &this_insn_sets);
+ if (r < 0)
+ continue;
- AND_COMPL_HARD_REG_SET (used_regs, call_fixed_reg_set);
- AND_COMPL_HARD_REG_SET (used_regs, this_insn_sets);
- AND_HARD_REG_SET (hard_regs_to_save, used_regs);
- for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
- if (TEST_HARD_REG_BIT (hard_regs_to_save, regno))
+ bound = r + hard_regno_nregs[r][PSEUDO_REGNO_MODE (regno)];
+ for (; r < bound; r++)
+ if (TEST_HARD_REG_BIT (used_regs, r))
{
- if (hard_reg_map[regno] != NULL)
- hard_reg_map[regno]->call_freq += freq;
+ if (hard_reg_map[r] != NULL)
+ hard_reg_map[r]->call_freq += freq;
else
- saved_reg = new_saved_hard_reg (regno, freq);
+ saved_reg = new_saved_hard_reg (r, freq);
+ SET_HARD_REG_BIT (hard_regs_to_save, r);
+ SET_HARD_REG_BIT (hard_regs_used, r);
}
- /* Look through all live pseudos, mark their hard registers. */
- EXECUTE_IF_SET_IN_REG_SET
- (&chain->live_throughout, FIRST_PSEUDO_REGISTER, regno, rsi)
- {
- int r = reg_renumber[regno];
- int bound;
+ }
+ }
- if (r < 0)
- continue;
+ /* If requested, figure out which hard regs can share save slots. */
+ if (optimize && flag_ira_share_save_slots)
+ {
+ rtx slot;
+ char *saved_reg_conflicts;
+ int next_k;
+ struct saved_hard_reg *saved_reg2, *saved_reg3;
+ int call_saved_regs_num;
+ struct saved_hard_reg *call_saved_regs[FIRST_PSEUDO_REGISTER];
+ int best_slot_num;
+ int prev_save_slots_num;
+ rtx prev_save_slots[FIRST_PSEUDO_REGISTER];
- bound = r + hard_regno_nregs[r][PSEUDO_REGNO_MODE (regno)];
- for (; r < bound; r++)
- if (TEST_HARD_REG_BIT (used_regs, r))
- {
- if (hard_reg_map[r] != NULL)
- hard_reg_map[r]->call_freq += freq;
- else
- saved_reg = new_saved_hard_reg (r, freq);
- SET_HARD_REG_BIT (hard_regs_to_save, r);
- }
- }
- }
/* Find saved hard register conflicts. */
saved_reg_conflicts = (char *) xmalloc (saved_regs_num * saved_regs_num);
memset (saved_reg_conflicts, 0, saved_regs_num * saved_regs_num);
}
else
{
- /* Now run through all the call-used hard-registers and allocate
- space for them in the caller-save area. Try to allocate space
+ /* We are not sharing slots.
+
+ Run through all the call-used hard-registers and allocate
+ space for each 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++)
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