void (*arm_lang_output_object_attributes_hook)(void);
/* Forward function declarations. */
+static int arm_compute_static_chain_stack_bytes (void);
static arm_stack_offsets *arm_get_frame_offsets (void);
static void arm_add_gc_roots (void);
static int arm_gen_constant (enum rtx_code, enum machine_mode, rtx,
}
+/* Compute the number of bytes used to store the static chain register on the
+ stack, above the stack frame. We need to know this accurately to get the
+ alignment of the rest of the stack frame correct. */
+
+static int arm_compute_static_chain_stack_bytes (void)
+{
+ unsigned long func_type = arm_current_func_type ();
+ int static_chain_stack_bytes = 0;
+
+ if (TARGET_APCS_FRAME && frame_pointer_needed && TARGET_ARM &&
+ IS_NESTED (func_type) &&
+ df_regs_ever_live_p (3) && crtl->args.pretend_args_size == 0)
+ static_chain_stack_bytes = 4;
+
+ return static_chain_stack_bytes;
+}
+
+
/* Compute a bit mask of which registers need to be
saved on the stack for the current function.
This is used by arm_get_frame_offsets, which may add extra registers. */
if (TARGET_REALLY_IWMMXT
&& ((bit_count (save_reg_mask)
- + ARM_NUM_INTS (crtl->args.pretend_args_size)) % 2) != 0)
+ + ARM_NUM_INTS (crtl->args.pretend_args_size +
+ arm_compute_static_chain_stack_bytes())
+ ) % 2) != 0)
{
/* The total number of registers that are going to be pushed
onto the stack is odd. We need to ensure that the stack
mask |= 1 << reg;
}
+ /* The 504 below is 8 bytes less than 512 because there are two possible
+ alignment words. We can't tell here if they will be present or not so we
+ have to play it safe and assume that they are. */
+ if ((CALLER_INTERWORKING_SLOT_SIZE +
+ ROUND_UP_WORD (get_frame_size ()) +
+ crtl->outgoing_args_size) >= 504)
+ {
+ /* This is the same as the code in thumb1_expand_prologue() which
+ determines which register to use for stack decrement. */
+ for (reg = LAST_ARG_REGNUM + 1; reg <= LAST_LO_REGNUM; reg++)
+ if (mask & (1 << reg))
+ break;
+
+ if (reg > LAST_LO_REGNUM)
+ {
+ /* Make sure we have a register available for stack decrement. */
+ mask |= 1 << LAST_LO_REGNUM;
+ }
+ }
+
return mask;
}
offsets->saved_args = crtl->args.pretend_args_size;
/* In Thumb mode this is incorrect, but never used. */
- offsets->frame = offsets->saved_args + (frame_pointer_needed ? 4 : 0);
+ offsets->frame = offsets->saved_args + (frame_pointer_needed ? 4 : 0) +
+ arm_compute_static_chain_stack_bytes();
if (TARGET_32BIT)
{
}
/* Saved registers include the stack frame. */
- offsets->saved_regs = offsets->saved_args + saved;
+ offsets->saved_regs = offsets->saved_args + saved +
+ arm_compute_static_chain_stack_bytes();
offsets->soft_frame = offsets->saved_regs + CALLER_INTERWORKING_SLOT_SIZE;
/* A leaf function does not need any stack alignment if it has nothing
on the stack. */
return offsets->soft_frame - offsets->saved_args;
case ARM_HARD_FRAME_POINTER_REGNUM:
- /* If there is no stack frame then the hard
- frame pointer and the arg pointer coincide. */
- if (offsets->frame == offsets->saved_regs)
- return 0;
- /* FIXME: Not sure about this. Maybe we should always return 0 ? */
- return (frame_pointer_needed
- && cfun->static_chain_decl != NULL
- && ! cfun->machine->uses_anonymous_args) ? 4 : 0;
+ /* This is only non-zero in the case where the static chain register
+ is stored above the frame. */
+ return offsets->frame - offsets->saved_args - 4;
case STACK_POINTER_REGNUM:
/* If nothing has been pushed on the stack at all
insn = emit_set_insn (gen_rtx_REG (SImode, 3), ip_rtx);
else if (args_to_push == 0)
{
+ gcc_assert(arm_compute_static_chain_stack_bytes() == 4);
+ saved_regs += 4;
+
rtx dwarf;
insn = gen_rtx_PRE_DEC (SImode, stack_pointer_rtx);
been pushed at the start of the prologue and so we can corrupt
it now. */
for (regno = LAST_ARG_REGNUM + 1; regno <= LAST_LO_REGNUM; regno++)
- if (live_regs_mask & (1 << regno)
- && !(frame_pointer_needed
- && (regno == THUMB_HARD_FRAME_POINTER_REGNUM)))
+ if (live_regs_mask & (1 << regno))
break;
- if (regno > LAST_LO_REGNUM) /* Very unlikely. */
- {
- rtx spare = gen_rtx_REG (SImode, IP_REGNUM);
-
- /* Choose an arbitrary, non-argument low register. */
- reg = gen_rtx_REG (SImode, LAST_LO_REGNUM);
-
- /* Save it by copying it into a high, scratch register. */
- emit_insn (gen_movsi (spare, reg));
- /* Add a USE to stop propagate_one_insn() from barfing. */
- emit_insn (gen_prologue_use (spare));
+ gcc_assert(regno <= LAST_LO_REGNUM);
- /* Decrement the stack. */
- emit_insn (gen_movsi (reg, GEN_INT (- amount)));
- insn = emit_insn (gen_addsi3 (stack_pointer_rtx,
- stack_pointer_rtx, reg));
- RTX_FRAME_RELATED_P (insn) = 1;
- dwarf = gen_rtx_SET (VOIDmode, stack_pointer_rtx,
- plus_constant (stack_pointer_rtx,
- -amount));
- RTX_FRAME_RELATED_P (dwarf) = 1;
- REG_NOTES (insn)
- = gen_rtx_EXPR_LIST (REG_FRAME_RELATED_EXPR, dwarf,
- REG_NOTES (insn));
-
- /* Restore the low register's original value. */
- emit_insn (gen_movsi (reg, spare));
-
- /* Emit a USE of the restored scratch register, so that flow
- analysis will not consider the restore redundant. The
- register won't be used again in this function and isn't
- restored by the epilogue. */
- emit_insn (gen_prologue_use (reg));
- }
- else
- {
- reg = gen_rtx_REG (SImode, regno);
+ reg = gen_rtx_REG (SImode, regno);
- emit_insn (gen_movsi (reg, GEN_INT (- amount)));
+ emit_insn (gen_movsi (reg, GEN_INT (- amount)));
- insn = emit_insn (gen_addsi3 (stack_pointer_rtx,
- stack_pointer_rtx, reg));
- RTX_FRAME_RELATED_P (insn) = 1;
- dwarf = gen_rtx_SET (VOIDmode, stack_pointer_rtx,
- plus_constant (stack_pointer_rtx,
- -amount));
- RTX_FRAME_RELATED_P (dwarf) = 1;
- REG_NOTES (insn)
- = gen_rtx_EXPR_LIST (REG_FRAME_RELATED_EXPR, dwarf,
- REG_NOTES (insn));
- }
+ insn = emit_insn (gen_addsi3 (stack_pointer_rtx,
+ stack_pointer_rtx, reg));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ dwarf = gen_rtx_SET (VOIDmode, stack_pointer_rtx,
+ plus_constant (stack_pointer_rtx,
+ -amount));
+ RTX_FRAME_RELATED_P (dwarf) = 1;
+ REG_NOTES (insn)
+ = gen_rtx_EXPR_LIST (REG_FRAME_RELATED_EXPR, dwarf,
+ REG_NOTES (insn));
}
}
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