/* Subroutines for manipulating rtx's in semantically interesting ways.
Copyright (C) 1987, 1991, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
+ Free Software Foundation, Inc.
This file is part of GCC.
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. */
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA. */
#include "config.h"
#include "ggc.h"
#include "recog.h"
#include "langhooks.h"
+#include "target.h"
+#include "output.h"
static rtx break_out_memory_refs (rtx);
static void emit_stack_probe (rtx);
int width = GET_MODE_BITSIZE (mode);
/* You want to truncate to a _what_? */
- if (! SCALAR_INT_MODE_P (mode))
- abort ();
+ gcc_assert (SCALAR_INT_MODE_P (mode));
/* Canonicalize BImode to 0 and STORE_FLAG_VALUE. */
if (mode == BImode)
if (TREE_CODE (exp) == WITH_SIZE_EXPR)
size = TREE_OPERAND (exp, 1);
else
- size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (lang_hooks.expr_size (exp), exp);
+ {
+ size = lang_hooks.expr_size (exp);
+ gcc_assert (size);
+ size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, exp);
+ }
return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype), 0);
}
if (TREE_CODE (exp) == WITH_SIZE_EXPR)
size = TREE_OPERAND (exp, 1);
else
- size = lang_hooks.expr_size (exp);
+ {
+ size = lang_hooks.expr_size (exp);
+ gcc_assert (size);
+ }
if (size == 0 || !host_integerp (size, 0))
return -1;
rtx x)
{
#ifndef POINTERS_EXTEND_UNSIGNED
+ gcc_assert (GET_MODE (x) == to_mode || GET_MODE (x) == VOIDmode);
return x;
#else /* defined(POINTERS_EXTEND_UNSIGNED) */
enum machine_mode from_mode;
case MULT:
/* For addition we can safely permute the conversion and addition
operation if one operand is a constant and converting the constant
- does not change it. We can always safely permute them if we are
- making the address narrower. */
+ does not change it or if one operand is a constant and we are
+ using a ptr_extend instruction (POINTERS_EXTEND_UNSIGNED < 0).
+ We can always safely permute them if we are making the address
+ narrower. */
if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode)
|| (GET_CODE (x) == PLUS
&& GET_CODE (XEXP (x, 1)) == CONST_INT
- && XEXP (x, 1) == convert_memory_address (to_mode, XEXP (x, 1))))
+ && (XEXP (x, 1) == convert_memory_address (to_mode, XEXP (x, 1))
+ || POINTERS_EXTEND_UNSIGNED < 0)))
return gen_rtx_fmt_ee (GET_CODE (x), to_mode,
convert_memory_address (to_mode, XEXP (x, 0)),
XEXP (x, 1));
x, POINTERS_EXTEND_UNSIGNED);
#endif /* defined(POINTERS_EXTEND_UNSIGNED) */
}
-
-/* Given a memory address or facsimile X, construct a new address,
- currently equivalent, that is stable: future stores won't change it.
-
- X must be composed of constants, register and memory references
- combined with addition, subtraction and multiplication:
- in other words, just what you can get from expand_expr if sum_ok is 1.
-
- Works by making copies of all regs and memory locations used
- by X and combining them the same way X does.
- You could also stabilize the reference to this address
- by copying the address to a register with copy_to_reg;
- but then you wouldn't get indexed addressing in the reference. */
-
-rtx
-copy_all_regs (rtx x)
-{
- if (REG_P (x))
- {
- if (REGNO (x) != FRAME_POINTER_REGNUM
-#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
- && REGNO (x) != HARD_FRAME_POINTER_REGNUM
-#endif
- )
- x = copy_to_reg (x);
- }
- else if (MEM_P (x))
- x = copy_to_reg (x);
- else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS
- || GET_CODE (x) == MULT)
- {
- rtx op0 = copy_all_regs (XEXP (x, 0));
- rtx op1 = copy_all_regs (XEXP (x, 1));
- if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
- x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
- }
- return x;
-}
\f
/* Return something equivalent to X but valid as a memory address
for something of mode MODE. When X is not itself valid, this
x = break_out_memory_refs (x);
/* At this point, any valid address is accepted. */
- GO_IF_LEGITIMATE_ADDRESS (mode, x, win);
+ if (memory_address_p (mode, x))
+ goto win;
/* If it was valid before but breaking out memory refs invalidated it,
use it the old way. */
win2:
x = oldx;
win:
- if (flag_force_addr && ! cse_not_expected && !REG_P (x)
- /* Don't copy an addr via a reg if it is one of our stack slots. */
- && ! (GET_CODE (x) == PLUS
- && (XEXP (x, 0) == virtual_stack_vars_rtx
- || XEXP (x, 0) == virtual_incoming_args_rtx)))
+ if (flag_force_addr && ! cse_not_expected && !REG_P (x))
{
- if (general_operand (x, Pmode))
- x = force_reg (Pmode, x);
- else
- x = force_operand (x, NULL_RTX);
+ x = force_operand (x, NULL_RTX);
+ x = force_reg (Pmode, x);
}
}
{
if (!MEM_P (ref))
return ref;
+ ref = use_anchored_address (ref);
if (! (flag_force_addr && CONSTANT_ADDRESS_P (XEXP (ref, 0)))
&& memory_address_p (GET_MODE (ref), XEXP (ref, 0)))
return ref;
/* Don't alter REF itself, since that is probably a stack slot. */
return replace_equiv_address (ref, XEXP (ref, 0));
}
-\f
-/* Given REF, either a MEM or a REG, and T, either the type of X or
- the expression corresponding to REF, set RTX_UNCHANGING_P if
- appropriate. */
-void
-maybe_set_unchanging (rtx ref, tree t)
-{
- /* We can set RTX_UNCHANGING_P from TREE_READONLY for decls whose
- initialization is only executed once, or whose initializer always
- has the same value. Currently we simplify this to PARM_DECLs in the
- first case, and decls with TREE_CONSTANT initializers in the second.
-
- We cannot do this for non-static aggregates, because of the double
- writes that can be generated by store_constructor, depending on the
- contents of the initializer. Yes, this does eliminate a good fraction
- of the number of uses of RTX_UNCHANGING_P for a language like Ada.
- It also eliminates a good quantity of bugs. Let this be incentive to
- eliminate RTX_UNCHANGING_P entirely in favor of a more reliable
- solution, perhaps based on alias sets. */
-
- if ((TREE_READONLY (t) && DECL_P (t)
- && (TREE_STATIC (t) || ! AGGREGATE_TYPE_P (TREE_TYPE (t)))
- && (TREE_CODE (t) == PARM_DECL
- || (DECL_INITIAL (t) && TREE_CONSTANT (DECL_INITIAL (t)))))
- || TREE_CODE_CLASS (TREE_CODE (t)) == 'c')
- RTX_UNCHANGING_P (ref) = 1;
-}
-\f
-/* Return a modified copy of X with its memory address copied
- into a temporary register to protect it from side effects.
- If X is not a MEM, it is returned unchanged (and not copied).
- Perhaps even if it is a MEM, if there is no need to change it. */
+/* If X is a memory reference to a member of an object block, try rewriting
+ it to use an anchor instead. Return the new memory reference on success
+ and the old one on failure. */
rtx
-stabilize (rtx x)
+use_anchored_address (rtx x)
{
- if (!MEM_P (x)
- || ! rtx_unstable_p (XEXP (x, 0)))
+ rtx base;
+ HOST_WIDE_INT offset;
+
+ if (!flag_section_anchors)
+ return x;
+
+ if (!MEM_P (x))
+ return x;
+
+ /* Split the address into a base and offset. */
+ base = XEXP (x, 0);
+ offset = 0;
+ if (GET_CODE (base) == CONST
+ && GET_CODE (XEXP (base, 0)) == PLUS
+ && GET_CODE (XEXP (XEXP (base, 0), 1)) == CONST_INT)
+ {
+ offset += INTVAL (XEXP (XEXP (base, 0), 1));
+ base = XEXP (XEXP (base, 0), 0);
+ }
+
+ /* Check whether BASE is suitable for anchors. */
+ if (GET_CODE (base) != SYMBOL_REF
+ || !SYMBOL_REF_HAS_BLOCK_INFO_P (base)
+ || SYMBOL_REF_ANCHOR_P (base)
+ || SYMBOL_REF_BLOCK (base) == NULL
+ || !targetm.use_anchors_for_symbol_p (base))
return x;
- return
- replace_equiv_address (x, force_reg (Pmode, copy_all_regs (XEXP (x, 0))));
+ /* Decide where BASE is going to be. */
+ place_block_symbol (base);
+
+ /* Get the anchor we need to use. */
+ offset += SYMBOL_REF_BLOCK_OFFSET (base);
+ base = get_section_anchor (SYMBOL_REF_BLOCK (base), offset,
+ SYMBOL_REF_TLS_MODEL (base));
+
+ /* Work out the offset from the anchor. */
+ offset -= SYMBOL_REF_BLOCK_OFFSET (base);
+
+ /* If we're going to run a CSE pass, force the anchor into a register.
+ We will then be able to reuse registers for several accesses, if the
+ target costs say that that's worthwhile. */
+ if (!cse_not_expected)
+ base = force_reg (GET_MODE (base), base);
+
+ return replace_equiv_address (x, plus_constant (base, offset));
}
\f
/* Copy the value or contents of X to a new temp reg and return that reg. */
if (! general_operand (x, VOIDmode))
x = force_operand (x, temp);
- if (GET_MODE (x) != mode && GET_MODE (x) != VOIDmode)
- abort ();
+ gcc_assert (GET_MODE (x) == mode || GET_MODE (x) == VOIDmode);
if (x != temp)
emit_move_insn (temp, x);
return temp;
align = MIN (sa, ca);
}
+ else if (MEM_P (x) && MEM_POINTER (x))
+ align = MEM_ALIGN (x);
if (align)
mark_reg_pointer (temp, align);
{
#ifdef PROMOTE_FUNCTION_MODE
case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
- case CHAR_TYPE: case REAL_TYPE: case OFFSET_TYPE:
+ case REAL_TYPE: case OFFSET_TYPE:
#ifdef PROMOTE_MODE
if (for_call)
{
/* Round the size of a block to be pushed up to the boundary required
by this machine. SIZE is the desired size, which need not be constant. */
-rtx
+static rtx
round_push (rtx size)
{
int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
rtx seq;
start_sequence ();
+ do_pending_stack_adjust ();
/* We must validize inside the sequence, to ensure that any instructions
created by the validize call also get moved to the right place. */
if (sa != 0)
}
else
{
+ do_pending_stack_adjust ();
if (sa != 0)
sa = validize_mem (sa);
emit_insn (fcn (sa, stack_pointer_rtx));
gen_rtx_MEM (BLKmode, stack_pointer_rtx)));
}
+ discard_pending_stack_adjust ();
+
if (after)
{
rtx seq;
emit_stack_save (SAVE_NONLOCAL, &r_save, NULL_RTX);
}
\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 (void)
-{
- rtx insn;
-
- for (insn = get_insns (); insn; insn = NEXT_INSN(insn))
- {
- rtx note;
-
- if (!NONJUMP_INSN_P (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
allocate_dynamic_stack_space (rtx size, 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 dereference it. But return a reasonable
address anyway. */
avoid clobbering the reg save area. Note that the offset of
virtual_incoming_args_rtx includes the preallocated stack args space.
It would be no problem to clobber that, but it's on the wrong side
- of the old save area. */
- {
- rtx dynamic_offset
- = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx,
- stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN);
+ of the old save area.
+
+ What used to happen is that, since we did not know for sure
+ whether setjmp() was invoked until after RTL generation, we
+ would use reg notes to store the "optimized" size and fix things
+ up later. These days we know this information before we ever
+ start building RTL so the reg notes are unnecessary. */
+ if (!current_function_calls_setjmp)
+ {
+ int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
- if (!current_function_calls_setjmp)
- {
- int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
-
- /* See optimize_save_area_alloca to understand what is being
- set up here. */
-
- /* ??? Code below assumes that the save area needs maximal
- alignment. This constraint may be too strong. */
- if (PREFERRED_STACK_BOUNDARY != BIGGEST_ALIGNMENT)
- abort ();
-
- if (GET_CODE (size) == CONST_INT)
- {
- HOST_WIDE_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 (!register_operand (setjmpless_size, Pmode))
- setjmpless_size = force_reg (Pmode, setjmpless_size);
- }
+ /* ??? Code below assumes that the save area needs maximal
+ alignment. This constraint may be too strong. */
+ gcc_assert (PREFERRED_STACK_BOUNDARY == BIGGEST_ALIGNMENT);
- size = expand_binop (Pmode, add_optab, size, dynamic_offset,
- NULL_RTX, 1, OPTAB_LIB_WIDEN);
- }
+ if (GET_CODE (size) == CONST_INT)
+ {
+ HOST_WIDE_INT new = INTVAL (size) / align * align;
+
+ if (INTVAL (size) != new)
+ size = GEN_INT (new);
+ }
+ else
+ {
+ /* Since we know overflow is not possible, we avoid using
+ CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
+ size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size,
+ GEN_INT (align), NULL_RTX, 1);
+ size = expand_mult (Pmode, size,
+ GEN_INT (align), NULL_RTX, 1);
+ }
+ }
+ else
+ {
+ rtx dynamic_offset
+ = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx,
+ stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN);
+
+ size = expand_binop (Pmode, add_optab, size, dynamic_offset,
+ NULL_RTX, 1, OPTAB_LIB_WIDEN);
+ }
#endif /* SETJMP_VIA_SAVE_AREA */
/* Round the size to a multiple of the required stack alignment.
/* We ought to be called always on the toplevel and stack ought to be aligned
properly. */
- if (stack_pointer_delta % (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT))
- abort ();
+ gcc_assert (!(stack_pointer_delta
+ % (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)));
/* If needed, check that we have the required amount of stack. Take into
account what has already been checked. */
}
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);
1, OPTAB_WIDEN);
#endif
- if (temp != test_addr)
- abort ();
+ gcc_assert (temp == test_addr);
emit_label (test_lab);
emit_cmp_and_jump_insns (test_addr, last_addr, CMP_OPCODE,
/* 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.
- FUNC is a FUNCTION_DECL node if the precise function is known,
- otherwise 0.
+ FUNC is a FUNCTION_DECL, FNTYPE a FUNCTION_TYPE node if the precise
+ function is known, otherwise 0.
OUTGOING is 1 if on a machine with register windows this function
should return the register in which the function will put its result
and 0 otherwise. */
rtx
-hard_function_value (tree valtype, tree func ATTRIBUTE_UNUSED,
+hard_function_value (tree valtype, tree func, tree fntype,
int outgoing ATTRIBUTE_UNUSED)
{
rtx val;
-#ifdef FUNCTION_OUTGOING_VALUE
- if (outgoing)
- val = FUNCTION_OUTGOING_VALUE (valtype, func);
- else
-#endif
- val = FUNCTION_VALUE (valtype, func);
+ val = targetm.calls.function_value (valtype, func ? func : fntype, outgoing);
if (REG_P (val)
&& GET_MODE (val) == BLKmode)
enum machine_mode tmpmode;
/* int_size_in_bytes can return -1. We don't need a check here
- since the value of bytes will be large enough that no mode
- will match and we will abort later in this function. */
+ since the value of bytes will then be large enough that no
+ mode will match anyway. */
for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
tmpmode != VOIDmode;
}
/* No suitable mode found. */
- if (tmpmode == VOIDmode)
- abort ();
+ gcc_assert (tmpmode != VOIDmode);
PUT_MODE (val, tmpmode);
}