/* Subroutines for manipulating rtx's in semantically interesting ways.
- Copyright (C) 1987, 1991, 1994 Free Software Foundation, Inc.
+ Copyright (C) 1987, 91, 94-97, 1998 Free Software Foundation, Inc.
This file is part of GNU CC.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
#include "config.h"
+#include "system.h"
#include "rtl.h"
#include "tree.h"
#include "flags.h"
#include "insn-flags.h"
#include "insn-codes.h"
+static rtx break_out_memory_refs PROTO((rtx));
+static void emit_stack_probe PROTO((rtx));
/* Return an rtx for the sum of X and the integer C.
This function should be used via the `plus_constant' macro. */
if (GET_CODE (XEXP (x, 0)) == SYMBOL_REF
&& CONSTANT_POOL_ADDRESS_P (XEXP (x, 0)))
{
+ /* Any rtl we create here must go in a saveable obstack, since
+ we might have been called from within combine. */
+ push_obstacks_nochange ();
+ rtl_in_saveable_obstack ();
tem
= force_const_mem (GET_MODE (x),
plus_constant (get_pool_constant (XEXP (x, 0)),
c));
+ pop_obstacks ();
if (memory_address_p (GET_MODE (tem), XEXP (tem, 0)))
return tem;
}
if (GET_CODE (XEXP (x, 1)) == CONST_INT)
return plus_constant (XEXP (x, 0), c + INTVAL (XEXP (x, 1)));
else if (CONSTANT_P (XEXP (x, 0)))
- return gen_rtx (PLUS, mode,
- plus_constant (XEXP (x, 0), c),
- XEXP (x, 1));
+ return gen_rtx_PLUS (mode,
+ plus_constant (XEXP (x, 0), c),
+ XEXP (x, 1));
else if (CONSTANT_P (XEXP (x, 1)))
- return gen_rtx (PLUS, mode,
- XEXP (x, 0),
- plus_constant (XEXP (x, 1), c));
+ return gen_rtx_PLUS (mode,
+ XEXP (x, 0),
+ plus_constant (XEXP (x, 1), c));
+ break;
+
+ default:
+ break;
}
if (c != 0)
- x = gen_rtx (PLUS, mode, x, GEN_INT (c));
+ x = gen_rtx_PLUS (mode, x, GEN_INT (c));
if (GET_CODE (x) == SYMBOL_REF || GET_CODE (x) == LABEL_REF)
return x;
else if (all_constant)
- return gen_rtx (CONST, mode, x);
+ return gen_rtx_CONST (mode, x);
else
return x;
}
register rtx x;
register HOST_WIDE_INT c;
{
- register RTX_CODE code = GET_CODE (x);
register enum machine_mode mode = GET_MODE (x);
- int all_constant = 0;
if (GET_CODE (x) == LO_SUM)
- return gen_rtx (LO_SUM, mode, XEXP (x, 0),
+ return gen_rtx_LO_SUM (mode, XEXP (x, 0),
plus_constant_for_output (XEXP (x, 1), c));
else
&& GET_CODE (tem) == CONST_INT)
{
*constptr = tem;
- return gen_rtx (PLUS, GET_MODE (x), x0, x1);
+ return gen_rtx_PLUS (GET_MODE (x), x0, x1);
}
return x;
&& contains_placeholder_p (size))
size = build (WITH_RECORD_EXPR, sizetype, size, exp);
- return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype), 0);
+ return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype),
+ EXPAND_MEMORY_USE_BAD);
}
\f
/* Return a copy of X in which all memory references
register rtx op1 = break_out_memory_refs (XEXP (x, 1));
if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
- x = gen_rtx (GET_CODE (x), Pmode, op0, op1);
+ x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
}
return x;
}
+#ifdef POINTERS_EXTEND_UNSIGNED
+
+/* Given X, a memory address in ptr_mode, convert it to an address
+ in Pmode, or vice versa (TO_MODE says which way). We take advantage of
+ the fact that pointers are not allowed to overflow by commuting arithmetic
+ operations over conversions so that address arithmetic insns can be
+ used. */
+
+rtx
+convert_memory_address (to_mode, x)
+ enum machine_mode to_mode;
+ rtx x;
+{
+ enum machine_mode from_mode = to_mode == ptr_mode ? Pmode : ptr_mode;
+ rtx temp;
+
+ /* Here we handle some special cases. If none of them apply, fall through
+ to the default case. */
+ switch (GET_CODE (x))
+ {
+ case CONST_INT:
+ case CONST_DOUBLE:
+ return x;
+
+ case LABEL_REF:
+ temp = gen_rtx_LABEL_REF (to_mode, XEXP (x, 0));
+ LABEL_REF_NONLOCAL_P (temp) = LABEL_REF_NONLOCAL_P (x);
+ return temp;
+
+ case SYMBOL_REF:
+ temp = gen_rtx_SYMBOL_REF (to_mode, XSTR (x, 0));
+ SYMBOL_REF_FLAG (temp) = SYMBOL_REF_FLAG (x);
+ CONSTANT_POOL_ADDRESS_P (temp) = CONSTANT_POOL_ADDRESS_P (x);
+ return temp;
+
+ case CONST:
+ return gen_rtx_CONST (to_mode,
+ convert_memory_address (to_mode, XEXP (x, 0)));
+
+ case PLUS:
+ case MULT:
+ /* For addition the second operand is a small constant, we can safely
+ permute the conversion and addition operation. We can always safely
+ permute them if we are making the address narrower. In addition,
+ always permute the operations if this is a constant. */
+ if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode)
+ || (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT
+ && (INTVAL (XEXP (x, 1)) + 20000 < 40000
+ || CONSTANT_P (XEXP (x, 0)))))
+ return gen_rtx_fmt_ee (GET_CODE (x), to_mode,
+ convert_memory_address (to_mode, XEXP (x, 0)),
+ convert_memory_address (to_mode, XEXP (x, 1)));
+ break;
+
+ default:
+ break;
+ }
+
+ return convert_modes (to_mode, from_mode,
+ x, POINTERS_EXTEND_UNSIGNED);
+}
+#endif
+
/* Given a memory address or facsimile X, construct a new address,
currently equivalent, that is stable: future stores won't change it.
register rtx op0 = copy_all_regs (XEXP (x, 0));
register rtx op1 = copy_all_regs (XEXP (x, 1));
if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
- x = gen_rtx (GET_CODE (x), Pmode, op0, op1);
+ x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
}
return x;
}
{
register rtx oldx = x;
+ if (GET_CODE (x) == ADDRESSOF)
+ return x;
+
+#ifdef POINTERS_EXTEND_UNSIGNED
+ if (GET_MODE (x) == ptr_mode)
+ x = convert_memory_address (Pmode, x);
+#endif
+
/* By passing constant addresses thru registers
we get a chance to cse them. */
if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x))
x = force_operand (x, NULL_RTX);
else
{
- y = gen_rtx (PLUS, GET_MODE (x), copy_to_reg (y), constant_term);
+ y = gen_rtx_PLUS (GET_MODE (x), copy_to_reg (y), constant_term);
if (! memory_address_p (mode, y))
x = force_operand (x, NULL_RTX);
else
}
}
- if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS)
+ else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS)
x = force_operand (x, NULL_RTX);
/* If we have a register that's an invalid address,
if (oldx == x)
return x;
else if (GET_CODE (x) == REG)
- mark_reg_pointer (x);
+ mark_reg_pointer (x, 1);
else if (GET_CODE (x) == PLUS
&& GET_CODE (XEXP (x, 0)) == REG
&& GET_CODE (XEXP (x, 1)) == CONST_INT)
- mark_reg_pointer (XEXP (x, 0));
+ mark_reg_pointer (XEXP (x, 0), 1);
/* OLDX may have been the address on a temporary. Update the address
to indicate that X is now used. */
rtx mem;
if (GET_CODE (temp) != REG)
temp = copy_to_reg (temp);
- mem = gen_rtx (MEM, GET_MODE (x), temp);
+ mem = gen_rtx_MEM (GET_MODE (x), temp);
/* Mark returned memref with in_struct if it's in an array or
structure. Copy const and volatile from original memref. */
if (note)
XEXP (note, 0) = x;
else
- REG_NOTES (insn) = gen_rtx (EXPR_LIST, REG_EQUAL, x, REG_NOTES (insn));
+ REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_EQUAL, x, REG_NOTES (insn));
}
return temp;
}
break;
#endif
+#ifdef POINTERS_EXTEND_UNSIGNED
+ case REFERENCE_TYPE:
case POINTER_TYPE:
+ mode = Pmode;
+ unsignedp = POINTERS_EXTEND_UNSIGNED;
+ break;
+#endif
+
+ default:
break;
}
else
{
/* CEIL_DIV_EXPR needs to worry about the addition overflowing,
- but we know it can't. So add ourselves and then do TRUNC_DIV_EXPR. */
+ but we know it can't. So add ourselves and then do
+ TRUNC_DIV_EXPR. */
size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1),
NULL_RTX, 1, OPTAB_LIB_WIDEN);
size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align),
rtx sa = *psave;
/* The default is that we use a move insn and save in a Pmode object. */
rtx (*fcn) () = gen_move_insn;
- enum machine_mode mode = Pmode;
+ enum machine_mode mode = STACK_SAVEAREA_MODE (save_level);
/* See if this machine has anything special to do for this kind of save. */
switch (save_level)
#ifdef HAVE_save_stack_block
case SAVE_BLOCK:
if (HAVE_save_stack_block)
- {
- fcn = gen_save_stack_block;
- mode = insn_operand_mode[CODE_FOR_save_stack_block][0];
- }
+ fcn = gen_save_stack_block;
break;
#endif
#ifdef HAVE_save_stack_function
case SAVE_FUNCTION:
if (HAVE_save_stack_function)
- {
- fcn = gen_save_stack_function;
- mode = insn_operand_mode[CODE_FOR_save_stack_function][0];
- }
+ fcn = gen_save_stack_function;
break;
#endif
#ifdef HAVE_save_stack_nonlocal
case SAVE_NONLOCAL:
if (HAVE_save_stack_nonlocal)
- {
- fcn = gen_save_stack_nonlocal;
- mode = insn_operand_mode[(int) CODE_FOR_save_stack_nonlocal][0];
- }
+ fcn = gen_save_stack_nonlocal;
break;
#endif
+ default:
+ break;
}
/* If there is no save area and we have to allocate one, do so. Otherwise
break;
#endif
#ifdef HAVE_restore_stack_nonlocal
-
case SAVE_NONLOCAL:
if (HAVE_restore_stack_nonlocal)
fcn = gen_restore_stack_nonlocal;
break;
#endif
+ default:
+ break;
}
if (sa != 0)
emit_insn (fcn (stack_pointer_rtx, sa));
}
\f
+#ifdef SETJMP_VIA_SAVE_AREA
+/* Optimize RTL generated by allocate_dynamic_stack_space for targets
+ where SETJMP_VIA_SAVE_AREA is true. The problem is that on these
+ platforms, the dynamic stack space used can corrupt the original
+ frame, thus causing a crash if a longjmp unwinds to it. */
+
+void
+optimize_save_area_alloca (insns)
+ rtx insns;
+{
+ rtx insn;
+
+ for (insn = insns; insn; insn = NEXT_INSN(insn))
+ {
+ rtx note;
+
+ if (GET_CODE (insn) != INSN)
+ continue;
+
+ for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
+ {
+ if (REG_NOTE_KIND (note) != REG_SAVE_AREA)
+ continue;
+
+ if (!current_function_calls_setjmp)
+ {
+ rtx pat = PATTERN (insn);
+
+ /* If we do not see the note in a pattern matching
+ these precise characteristics, we did something
+ entirely wrong in allocate_dynamic_stack_space.
+
+ Note, one way this could happen is if SETJMP_VIA_SAVE_AREA
+ was defined on a machine where stacks grow towards higher
+ addresses.
+
+ Right now only supported port with stack that grow upward
+ is the HPPA and it does not define SETJMP_VIA_SAVE_AREA. */
+ if (GET_CODE (pat) != SET
+ || SET_DEST (pat) != stack_pointer_rtx
+ || GET_CODE (SET_SRC (pat)) != MINUS
+ || XEXP (SET_SRC (pat), 0) != stack_pointer_rtx)
+ abort ();
+
+ /* This will now be transformed into a (set REG REG)
+ so we can just blow away all the other notes. */
+ XEXP (SET_SRC (pat), 1) = XEXP (note, 0);
+ REG_NOTES (insn) = NULL_RTX;
+ }
+ else
+ {
+ /* setjmp was called, we must remove the REG_SAVE_AREA
+ note so that later passes do not get confused by its
+ presence. */
+ if (note == REG_NOTES (insn))
+ {
+ REG_NOTES (insn) = XEXP (note, 1);
+ }
+ else
+ {
+ rtx srch;
+
+ for (srch = REG_NOTES (insn); srch; srch = XEXP (srch, 1))
+ if (XEXP (srch, 1) == note)
+ break;
+
+ if (srch == NULL_RTX)
+ abort();
+
+ XEXP (srch, 1) = XEXP (note, 1);
+ }
+ }
+ /* Once we've seen the note of interest, we need not look at
+ the rest of them. */
+ break;
+ }
+ }
+}
+#endif /* SETJMP_VIA_SAVE_AREA */
+
/* Return an rtx representing the address of an area of memory dynamically
pushed on the stack. This region of memory is always aligned to
a multiple of BIGGEST_ALIGNMENT.
rtx target;
int known_align;
{
+#ifdef SETJMP_VIA_SAVE_AREA
+ rtx setjmpless_size = NULL_RTX;
+#endif
+
/* If we're asking for zero bytes, it doesn't matter what we point
- to since we can't derefference it. But return a reasonable
+ to since we can't dereference it. But return a reasonable
address anyway. */
if (size == const0_rtx)
return virtual_stack_dynamic_rtx;
If we have to align, we must leave space in SIZE for the hole
that might result from the alignment operation. */
-#if defined (STACK_DYNAMIC_OFFSET) || defined(STACK_POINTER_OFFSET) || defined (ALLOCATE_OUTGOING_ARGS)
-#define MUST_ALIGN
-#endif
-
-#if ! defined (MUST_ALIGN) && (!defined(STACK_BOUNDARY) || STACK_BOUNDARY < BIGGEST_ALIGNMENT)
-#define MUST_ALIGN
+#if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || ! defined (STACK_BOUNDARY)
+#define MUST_ALIGN 1
+#else
+#define MUST_ALIGN (STACK_BOUNDARY < BIGGEST_ALIGNMENT)
#endif
-#ifdef MUST_ALIGN
-
-#if 0 /* It turns out we must always make extra space, if MUST_ALIGN
- because we must always round the address up at the end,
- because we don't know whether the dynamic offset
- will mess up the desired alignment. */
- /* If we have to round the address up regardless of known_align,
- make extra space regardless, also. */
- if (known_align % BIGGEST_ALIGNMENT != 0)
-#endif
+ if (MUST_ALIGN)
{
if (GET_CODE (size) == CONST_INT)
size = GEN_INT (INTVAL (size)
NULL_RTX, 1, OPTAB_LIB_WIDEN);
}
-#endif
-
#ifdef SETJMP_VIA_SAVE_AREA
/* If setjmp restores regs from a save area in the stack frame,
avoid clobbering the reg save area. Note that the offset of
rtx dynamic_offset
= expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx,
stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN);
+
+ if (!current_function_calls_setjmp)
+ {
+ int align = STACK_BOUNDARY / BITS_PER_UNIT;
+
+ /* See optimize_save_area_alloca to understand what is being
+ set up here. */
+
+#if !defined(STACK_BOUNDARY) || !defined(MUST_ALIGN) || (STACK_BOUNDARY != BIGGEST_ALIGNMENT)
+ /* If anyone creates a target with these characteristics, let them
+ know that our optimization cannot work correctly in such a case. */
+ abort();
+#endif
+
+ if (GET_CODE (size) == CONST_INT)
+ {
+ int new = INTVAL (size) / align * align;
+
+ if (INTVAL (size) != new)
+ setjmpless_size = GEN_INT (new);
+ else
+ setjmpless_size = size;
+ }
+ else
+ {
+ /* Since we know overflow is not possible, we avoid using
+ CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
+ setjmpless_size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size,
+ GEN_INT (align), NULL_RTX, 1);
+ setjmpless_size = expand_mult (Pmode, setjmpless_size,
+ GEN_INT (align), NULL_RTX, 1);
+ }
+ /* Our optimization works based upon being able to perform a simple
+ transformation of this RTL into a (set REG REG) so make sure things
+ did in fact end up in a REG. */
+ if (!arith_operand (setjmpless_size, Pmode))
+ setjmpless_size = force_reg (Pmode, setjmpless_size);
+ }
+
size = expand_binop (Pmode, add_optab, size, dynamic_offset,
NULL_RTX, 1, OPTAB_LIB_WIDEN);
}
#ifdef STACK_BOUNDARY
/* If we added a variable amount to SIZE,
we can no longer assume it is aligned. */
-#if !defined (SETJMP_VIA_SAVE_AREA) && !defined (MUST_ALIGN)
- if (known_align % STACK_BOUNDARY != 0)
+#if !defined (SETJMP_VIA_SAVE_AREA)
+ if (MUST_ALIGN || known_align % STACK_BOUNDARY != 0)
#endif
size = round_push (size);
#endif
do_pending_stack_adjust ();
+ /* If needed, check that we have the required amount of stack. Take into
+ account what has already been checked. */
+ if (flag_stack_check && ! STACK_CHECK_BUILTIN)
+ probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE + STACK_CHECK_PROTECT, size);
+
/* Don't use a TARGET that isn't a pseudo. */
if (target == 0 || GET_CODE (target) != REG
|| REGNO (target) < FIRST_PSEUDO_REGISTER)
target = gen_reg_rtx (Pmode);
- mark_reg_pointer (target);
-
-#ifndef STACK_GROWS_DOWNWARD
- emit_move_insn (target, virtual_stack_dynamic_rtx);
-#endif
+ mark_reg_pointer (target, known_align / BITS_PER_UNIT);
/* Perform the required allocation from the stack. Some systems do
this differently than simply incrementing/decrementing from the
- stack pointer. */
+ stack pointer, such as acquiring the space by calling malloc(). */
#ifdef HAVE_allocate_stack
if (HAVE_allocate_stack)
{
- enum machine_mode mode
- = insn_operand_mode[(int) CODE_FOR_allocate_stack][0];
-
if (insn_operand_predicate[(int) CODE_FOR_allocate_stack][0]
&& ! ((*insn_operand_predicate[(int) CODE_FOR_allocate_stack][0])
- (size, mode)))
- size = copy_to_mode_reg (mode, size);
-
- emit_insn (gen_allocate_stack (size));
+ (target, Pmode)))
+ target = copy_to_mode_reg (Pmode, target);
+ size = convert_modes (Pmode, ptr_mode, size, 1);
+ if (insn_operand_predicate[(int) CODE_FOR_allocate_stack][1]
+ && ! ((*insn_operand_predicate[(int) CODE_FOR_allocate_stack][1])
+ (size, Pmode)))
+ size = copy_to_mode_reg (Pmode, size);
+
+ emit_insn (gen_allocate_stack (target, size));
}
else
#endif
- anti_adjust_stack (size);
+ {
+#ifndef STACK_GROWS_DOWNWARD
+ emit_move_insn (target, virtual_stack_dynamic_rtx);
+#endif
+ size = convert_modes (Pmode, ptr_mode, size, 1);
+ anti_adjust_stack (size);
+#ifdef SETJMP_VIA_SAVE_AREA
+ if (setjmpless_size != NULL_RTX)
+ {
+ rtx note_target = get_last_insn ();
+ REG_NOTES (note_target) = gen_rtx (EXPR_LIST, REG_SAVE_AREA,
+ setjmpless_size,
+ REG_NOTES (note_target));
+ }
+#endif /* SETJMP_VIA_SAVE_AREA */
#ifdef STACK_GROWS_DOWNWARD
emit_move_insn (target, virtual_stack_dynamic_rtx);
#endif
+ }
-#ifdef MUST_ALIGN
-#if 0 /* Even if we know the stack pointer has enough alignment,
- there's no way to tell whether virtual_stack_dynamic_rtx shares that
- alignment, so we still need to round the address up. */
- if (known_align % BIGGEST_ALIGNMENT != 0)
-#endif
+ if (MUST_ALIGN)
{
/* CEIL_DIV_EXPR needs to worry about the addition overflowing,
- but we know it can't. So add ourselves and then do TRUNC_DIV_EXPR. */
+ but we know it can't. So add ourselves and then do
+ TRUNC_DIV_EXPR. */
target = expand_binop (Pmode, add_optab, target,
GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
NULL_RTX, 1, OPTAB_LIB_WIDEN);
GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
NULL_RTX, 1);
}
-#endif
/* Some systems require a particular insn to refer to the stack
to make the pages exist. */
return target;
}
\f
+/* Emit one stack probe at ADDRESS, an address within the stack. */
+
+static void
+emit_stack_probe (address)
+ rtx address;
+{
+ rtx memref = gen_rtx_MEM (word_mode, address);
+
+ MEM_VOLATILE_P (memref) = 1;
+
+ if (STACK_CHECK_PROBE_LOAD)
+ emit_move_insn (gen_reg_rtx (word_mode), memref);
+ else
+ emit_move_insn (memref, const0_rtx);
+}
+
+/* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
+ FIRST is a constant and size is a Pmode RTX. These are offsets from the
+ current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
+ subtract from the stack. If SIZE is constant, this is done
+ with a fixed number of probes. Otherwise, we must make a loop. */
+
+#ifdef STACK_GROWS_DOWNWARD
+#define STACK_GROW_OP MINUS
+#else
+#define STACK_GROW_OP PLUS
+#endif
+
+void
+probe_stack_range (first, size)
+ HOST_WIDE_INT first;
+ rtx size;
+{
+ /* First see if we have an insn to check the stack. Use it if so. */
+#ifdef HAVE_check_stack
+ if (HAVE_check_stack)
+ {
+ rtx last_addr
+ = force_operand (gen_rtx_STACK_GROW_OP (Pmode,
+ stack_pointer_rtx,
+ plus_constant (size, first)),
+ NULL_RTX);
+
+ if (insn_operand_predicate[(int) CODE_FOR_check_stack][0]
+ && ! ((*insn_operand_predicate[(int) CODE_FOR_check_stack][0])
+ (last_address, Pmode)))
+ last_address = copy_to_mode_reg (Pmode, last_address);
+
+ emit_insn (gen_check_stack (last_address));
+ return;
+ }
+#endif
+
+ /* If we have to generate explicit probes, see if we have a constant
+ small number of them to generate. If so, that's the easy case. */
+ if (GET_CODE (size) == CONST_INT
+ && INTVAL (size) < 10 * STACK_CHECK_PROBE_INTERVAL)
+ {
+ HOST_WIDE_INT offset;
+
+ /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL
+ for values of N from 1 until it exceeds LAST. If only one
+ probe is needed, this will not generate any code. Then probe
+ at LAST. */
+ for (offset = first + STACK_CHECK_PROBE_INTERVAL;
+ offset < INTVAL (size);
+ offset = offset + STACK_CHECK_PROBE_INTERVAL)
+ emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
+ stack_pointer_rtx,
+ GEN_INT (offset)));
+
+ emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
+ stack_pointer_rtx,
+ plus_constant (size, first)));
+ }
+
+ /* In the variable case, do the same as above, but in a loop. We emit loop
+ notes so that loop optimization can be done. */
+ else
+ {
+ rtx test_addr
+ = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
+ stack_pointer_rtx,
+ GEN_INT (first + STACK_CHECK_PROBE_INTERVAL)),
+ NULL_RTX);
+ rtx last_addr
+ = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
+ stack_pointer_rtx,
+ plus_constant (size, first)),
+ NULL_RTX);
+ rtx incr = GEN_INT (STACK_CHECK_PROBE_INTERVAL);
+ rtx loop_lab = gen_label_rtx ();
+ rtx test_lab = gen_label_rtx ();
+ rtx end_lab = gen_label_rtx ();
+ rtx temp;
+
+ if (GET_CODE (test_addr) != REG
+ || REGNO (test_addr) < FIRST_PSEUDO_REGISTER)
+ test_addr = force_reg (Pmode, test_addr);
+
+ emit_note (NULL_PTR, NOTE_INSN_LOOP_BEG);
+ emit_jump (test_lab);
+
+ emit_label (loop_lab);
+ emit_stack_probe (test_addr);
+
+ emit_note (NULL_PTR, NOTE_INSN_LOOP_CONT);
+
+#ifdef STACK_GROWS_DOWNWARD
+#define CMP_OPCODE GTU
+ temp = expand_binop (Pmode, sub_optab, test_addr, incr, test_addr,
+ 1, OPTAB_WIDEN);
+#else
+#define CMP_OPCODE LTU
+ temp = expand_binop (Pmode, add_optab, test_addr, incr, test_addr,
+ 1, OPTAB_WIDEN);
+#endif
+
+ if (temp != test_addr)
+ abort ();
+
+ emit_label (test_lab);
+ emit_cmp_insn (test_addr, last_addr, CMP_OPCODE, NULL_RTX, Pmode, 1, 0);
+ emit_jump_insn ((*bcc_gen_fctn[(int) CMP_OPCODE]) (loop_lab));
+ emit_jump (end_lab);
+ emit_note (NULL_PTR, NOTE_INSN_LOOP_END);
+ emit_label (end_lab);
+
+ /* If will be doing stupid optimization, show test_addr is still live. */
+ if (obey_regdecls)
+ emit_insn (gen_rtx_USE (VOIDmode, test_addr));
+
+ emit_stack_probe (last_addr);
+ }
+}
+\f
/* Return an rtx representing the register or memory location
in which a scalar value of data type VALTYPE
was returned by a function call to function FUNC.
tree valtype;
tree func;
{
- return FUNCTION_VALUE (valtype, func);
+ rtx val = FUNCTION_VALUE (valtype, func);
+ if (GET_CODE (val) == REG
+ && GET_MODE (val) == BLKmode)
+ {
+ int bytes = int_size_in_bytes (valtype);
+ enum machine_mode tmpmode;
+ for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
+ tmpmode != MAX_MACHINE_MODE;
+ tmpmode = GET_MODE_WIDER_MODE (tmpmode))
+ {
+ /* Have we found a large enough mode? */
+ if (GET_MODE_SIZE (tmpmode) >= bytes)
+ break;
+ }
+
+ /* No suitable mode found. */
+ if (tmpmode == MAX_MACHINE_MODE)
+ abort ();
+
+ PUT_MODE (val, tmpmode);
+ }
+ return val;
}
/* Return an rtx representing the register or memory location
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