/* Subroutines for manipulating rtx's in semantically interesting ways.
- Copyright (C) 1987, 1991, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ Copyright (C) 1987, 1991, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
+ 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
Free Software Foundation, Inc.
This file is part of GCC.
#include "recog.h"
#include "langhooks.h"
#include "target.h"
+#include "common/common-target.h"
#include "output.h"
static rtx break_out_memory_refs (rtx);
HOST_WIDE_INT
trunc_int_for_mode (HOST_WIDE_INT c, enum machine_mode mode)
{
- int width = GET_MODE_BITSIZE (mode);
+ int width = GET_MODE_PRECISION (mode);
/* You want to truncate to a _what_? */
gcc_assert (SCALAR_INT_MODE_P (mode));
case PLUS:
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 or if one operand is a constant and we are
- using a ptr_extend instruction (POINTERS_EXTEND_UNSIGNED < 0).
+ /* FIXME: For addition, we used to permute the conversion and
+ addition operation only if one operand is a constant and
+ converting the constant does not change it or if one operand
+ is a constant and we are using a ptr_extend instruction
+ (POINTERS_EXTEND_UNSIGNED < 0) even if the resulting address
+ may overflow/underflow. We relax the condition to include
+ zero-extend (POINTERS_EXTEND_UNSIGNED > 0) since the other
+ parts of the compiler depend on it. See PR 49721.
+
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
&& CONST_INT_P (XEXP (x, 1))
- && (XEXP (x, 1) == convert_memory_address_addr_space
- (to_mode, XEXP (x, 1), as)
- || POINTERS_EXTEND_UNSIGNED < 0)))
+ && (POINTERS_EXTEND_UNSIGNED != 0
+ || XEXP (x, 1) == convert_memory_address_addr_space
+ (to_mode, XEXP (x, 1), as))))
return gen_rtx_fmt_ee (GET_CODE (x), to_mode,
convert_memory_address_addr_space
(to_mode, XEXP (x, 0), as),
}
\f
+/* Controls the behaviour of {anti_,}adjust_stack. */
+static bool suppress_reg_args_size;
+
+/* A helper for adjust_stack and anti_adjust_stack. */
+
+static void
+adjust_stack_1 (rtx adjust, bool anti_p)
+{
+ rtx temp, insn;
+
+#ifndef STACK_GROWS_DOWNWARD
+ /* Hereafter anti_p means subtract_p. */
+ anti_p = !anti_p;
+#endif
+
+ temp = expand_binop (Pmode,
+ anti_p ? sub_optab : add_optab,
+ stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
+ OPTAB_LIB_WIDEN);
+
+ if (temp != stack_pointer_rtx)
+ insn = emit_move_insn (stack_pointer_rtx, temp);
+ else
+ {
+ insn = get_last_insn ();
+ temp = single_set (insn);
+ gcc_assert (temp != NULL && SET_DEST (temp) == stack_pointer_rtx);
+ }
+
+ if (!suppress_reg_args_size)
+ add_reg_note (insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
+}
+
/* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
This pops when ADJUST is positive. ADJUST need not be constant. */
void
adjust_stack (rtx adjust)
{
- rtx temp;
-
if (adjust == const0_rtx)
return;
if (CONST_INT_P (adjust))
stack_pointer_delta -= INTVAL (adjust);
- temp = expand_binop (Pmode,
-#ifdef STACK_GROWS_DOWNWARD
- add_optab,
-#else
- sub_optab,
-#endif
- stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
- OPTAB_LIB_WIDEN);
-
- if (temp != stack_pointer_rtx)
- emit_move_insn (stack_pointer_rtx, temp);
+ adjust_stack_1 (adjust, false);
}
/* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
void
anti_adjust_stack (rtx adjust)
{
- rtx temp;
-
if (adjust == const0_rtx)
return;
if (CONST_INT_P (adjust))
stack_pointer_delta += INTVAL (adjust);
- temp = expand_binop (Pmode,
-#ifdef STACK_GROWS_DOWNWARD
- sub_optab,
-#else
- add_optab,
-#endif
- stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
- OPTAB_LIB_WIDEN);
-
- if (temp != stack_pointer_rtx)
- emit_move_insn (stack_pointer_rtx, temp);
+ adjust_stack_1 (adjust, true);
}
/* Round the size of a block to be pushed up to the boundary required
/* The default is that we use a move insn. */
rtx (*fcn) (rtx, rtx) = gen_move_insn;
+ /* If stack_realign_drap, the x86 backend emits a prologue that aligns both
+ STACK_POINTER and HARD_FRAME_POINTER.
+ If stack_realign_fp, the x86 backend emits a prologue that aligns only
+ STACK_POINTER. This renders the HARD_FRAME_POINTER unusable for accessing
+ aligned variables, which is reflected in ix86_can_eliminate.
+ We normally still have the realigned STACK_POINTER that we can use.
+ But if there is a stack restore still present at reload, it can trigger
+ mark_not_eliminable for the STACK_POINTER, leaving no way to eliminate
+ FRAME_POINTER into a hard reg.
+ To prevent this situation, we force need_drap if we emit a stack
+ restore. */
+ if (SUPPORTS_STACK_ALIGNMENT)
+ crtl->need_drap = true;
+
/* See if this machine has anything special to do for this kind of save. */
switch (save_level)
{
first one is used for the frame pointer save; the rest are sized by
STACK_SAVEAREA_MODE. Create a reference to array index 1, the first
of the stack save area slots. */
- t_save = build4 (ARRAY_REF, ptr_type_node, cfun->nonlocal_goto_save_area,
+ t_save = build4 (ARRAY_REF,
+ TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
+ cfun->nonlocal_goto_save_area,
integer_one_node, NULL_TREE, NULL_TREE);
r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
size_align = extra_align;
}
-#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
- 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.
-
- 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 (cfun->calls_setjmp)
- {
- 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);
-
- /* The above dynamic offset cannot be computed statically at this
- point, but it will be possible to do so after RTL expansion is
- done. Record how many times we will need to add it. */
- if (flag_stack_usage_info)
- current_function_dynamic_alloc_count++;
-
- /* ??? Can we infer a minimum of STACK_BOUNDARY here? */
- size_align = BITS_PER_UNIT;
- }
-#endif /* SETJMP_VIA_SAVE_AREA */
-
/* Round the size to a multiple of the required stack alignment.
Since the stack if presumed to be rounded before this allocation,
this will maintain the required alignment.
else if (flag_stack_check == STATIC_BUILTIN_STACK_CHECK)
probe_stack_range (STACK_CHECK_PROTECT, size);
+ /* Don't let anti_adjust_stack emit notes. */
+ suppress_reg_args_size = true;
+
/* Perform the required allocation from the stack. Some systems do
this differently than simply incrementing/decrementing from the
stack pointer, such as acquiring the space by calling malloc(). */
}
saved_stack_pointer_delta = stack_pointer_delta;
+
if (flag_stack_check && STACK_CHECK_MOVING_SP)
anti_adjust_stack_and_probe (size, false);
else
anti_adjust_stack (size);
+
/* Even if size is constant, don't modify stack_pointer_delta.
The constant size alloca should preserve
crtl->preferred_stack_boundary alignment. */
#endif
}
+ suppress_reg_args_size = false;
+
/* Finish up the split stack handling. */
if (final_label != NULL_RTX)
{
plus_constant (size, first)));
emit_library_call (stack_check_libfunc, LCT_NORMAL, VOIDmode, 1, addr,
Pmode);
- return;
}
/* Next see if we have an insn to check the stack. */
#ifdef HAVE_check_stack
- if (HAVE_check_stack)
+ else if (HAVE_check_stack)
{
struct expand_operand ops[1];
rtx addr = memory_address (Pmode,
gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
stack_pointer_rtx,
plus_constant (size, first)));
-
+ bool success;
create_input_operand (&ops[0], addr, Pmode);
- if (maybe_expand_insn (CODE_FOR_check_stack, 1, ops))
- return;
+ success = maybe_expand_insn (CODE_FOR_check_stack, 1, ops);
+ gcc_assert (success);
}
#endif