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riscv-gcc-1
Commit ddc6e7d6 by Richard Henderson Committed by Richard Henderson
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arm: Use REG_CFA_REGISTER instead of UNSPEC_STACK_ALIGN. 

This requires a bit of extra preparation in arm_unwind_emit, in
order to handle the change for ARM unwinding.

        * config/arm/arm.c (arm_dwarf_handle_frame_unspec): Remove.
        (TARGET_DWARF_HANDLE_FRAME_UNSPEC): Remove.
        (arm_expand_prologue): Use REG_CFA_REGISTER to mark the
        stack pointer save.
        (arm_unwind_emit_set): Don't recognize UNSPEC_STACK_ALIGN.
        (arm_unwind_emit): Walk REG_NOTES for unwinding notes.  Emit
        proper unwind info for a REG_CFA_REGISTER save of stack pointer.
        * config/arm/arm.md (UNSPEC_STACK_ALIGN): Remove.

From-SVN: r175870
parent a3515605
Showing with 73 additions and 54 deletions
gcc/ChangeLog
2011-07-05 Richard Henderson <rth@redhat.com>
* config/arm/arm.c (arm_dwarf_handle_frame_unspec): Remove.
(TARGET_DWARF_HANDLE_FRAME_UNSPEC): Remove.
(arm_expand_prologue): Use REG_CFA_REGISTER to mark the
stack pointer save.
(arm_unwind_emit_set): Don't recognize UNSPEC_STACK_ALIGN.
(arm_unwind_emit): Walk REG_NOTES for unwinding notes. Emit
proper unwind info for a REG_CFA_REGISTER save of stack pointer.
* config/arm/arm.md (UNSPEC_STACK_ALIGN): Remove.
2011-07-05 Richard Henderson <rth@redhat.com>
* config/vax/vax.md (define_c_enum unspecv): New. Define the
VUNSPEC_* constants here instead of via define_constants.
(VUNSPEC_PEM): New constant.
......
gcc/config/arm/arm.c
......@@ -203,7 +203,6 @@ static bool arm_output_ttype (rtx);
static void arm_asm_emit_except_personality (rtx);
static void arm_asm_init_sections (void);
#endif
static void arm_dwarf_handle_frame_unspec (const char *, rtx, int);
static rtx arm_dwarf_register_span (rtx);
static tree arm_cxx_guard_type (void);
......@@ -501,9 +500,6 @@ static const struct attribute_spec arm_attribute_table[] =
#define TARGET_ASM_INIT_SECTIONS arm_asm_init_sections
#endif /* ARM_UNWIND_INFO */
#undef TARGET_DWARF_HANDLE_FRAME_UNSPEC
#define TARGET_DWARF_HANDLE_FRAME_UNSPEC arm_dwarf_handle_frame_unspec
#undef TARGET_DWARF_REGISTER_SPAN
#define TARGET_DWARF_REGISTER_SPAN arm_dwarf_register_span
......@@ -15830,9 +15826,8 @@ arm_expand_prologue (void)
if (IS_STACKALIGN (func_type))
{
rtx dwarf;
rtx r0;
rtx r1;
rtx r0, r1;
/* Handle a word-aligned stack pointer. We generate the following:
mov r0, sp
......@@ -15848,15 +15843,18 @@ arm_expand_prologue (void)
r0 = gen_rtx_REG (SImode, 0);
r1 = gen_rtx_REG (SImode, 1);
/* Use a real rtvec rather than NULL_RTVEC so the rest of the
compiler won't choke. */
dwarf = gen_rtx_UNSPEC (SImode, rtvec_alloc (0), UNSPEC_STACK_ALIGN);
dwarf = gen_rtx_SET (VOIDmode, r0, dwarf);
insn = gen_movsi (r0, stack_pointer_rtx);
insn = emit_insn (gen_movsi (r0, stack_pointer_rtx));
RTX_FRAME_RELATED_P (insn) = 1;
add_reg_note (insn, REG_FRAME_RELATED_EXPR, dwarf);
emit_insn (insn);
add_reg_note (insn, REG_CFA_REGISTER, NULL);
emit_insn (gen_andsi3 (r1, r0, GEN_INT (~(HOST_WIDE_INT)7)));
/* ??? The CFA changes here, which may cause GDB to conclude that it
has entered a different function. That said, the unwind info is
correct, individually, before and after this instruction because
we've described the save of SP, which will override the default
handling of SP as restoring from the CFA. */
emit_insn (gen_movsi (stack_pointer_rtx, r1));
}
......@@ -22880,13 +22878,6 @@ arm_unwind_emit_set (FILE * asm_out_file, rtx p)
asm_fprintf (asm_out_file, "\t.movsp %r, #%d\n",
REGNO (e0), (int)INTVAL(XEXP (e1, 1)));
}
else if (GET_CODE (e1) == UNSPEC && XINT (e1, 1) == UNSPEC_STACK_ALIGN)
{
/* Stack pointer save before alignment. */
reg = REGNO (e0);
asm_fprintf (asm_out_file, "\t.unwind_raw 0, 0x%x @ vsp = r%d\n",
reg + 0x90, reg);
}
else
abort ();
break;
......@@ -22902,7 +22893,8 @@ arm_unwind_emit_set (FILE * asm_out_file, rtx p)
static void
arm_unwind_emit (FILE * asm_out_file, rtx insn)
{
rtx pat;
rtx note, pat;
bool handled_one = false;
if (arm_except_unwind_info (&global_options) != UI_TARGET)
return;
......@@ -22912,14 +22904,56 @@ arm_unwind_emit (FILE * asm_out_file, rtx insn)
|| crtl->all_throwers_are_sibcalls))
return;
if (GET_CODE (insn) == NOTE || !RTX_FRAME_RELATED_P (insn))
if (NOTE_P (insn) || !RTX_FRAME_RELATED_P (insn))
return;
pat = find_reg_note (insn, REG_FRAME_RELATED_EXPR, NULL_RTX);
if (pat)
pat = XEXP (pat, 0);
else
pat = PATTERN (insn);
for (note = REG_NOTES (insn); note ; note = XEXP (note, 1))
{
pat = XEXP (note, 0);
switch (REG_NOTE_KIND (note))
{
case REG_FRAME_RELATED_EXPR:
goto found;
case REG_CFA_REGISTER:
if (pat == NULL)
{
pat = PATTERN (insn);
if (GET_CODE (pat) == PARALLEL)
pat = XVECEXP (pat, 0, 0);
}
/* Only emitted for IS_STACKALIGN re-alignment. */
{
rtx dest, src;
unsigned reg;
src = SET_SRC (pat);
dest = SET_DEST (pat);
gcc_assert (src == stack_pointer_rtx);
reg = REGNO (dest);
asm_fprintf (asm_out_file, "\t.unwind_raw 0, 0x%x @ vsp = r%d\n",
reg + 0x90, reg);
}
handled_one = true;
break;
case REG_CFA_DEF_CFA:
case REG_CFA_EXPRESSION:
case REG_CFA_ADJUST_CFA:
case REG_CFA_OFFSET:
/* ??? Only handling here what we actually emit. */
gcc_unreachable ();
default:
break;
}
}
if (handled_one)
return;
pat = PATTERN (insn);
found:
switch (GET_CODE (pat))
{
......@@ -22975,30 +23009,6 @@ arm_asm_init_sections (void)
}
#endif /* ARM_UNWIND_INFO */
/* Handle UNSPEC DWARF call frame instructions. These are needed for dynamic
stack alignment. */
static void
arm_dwarf_handle_frame_unspec (const char *label, rtx pattern, int index)
{
rtx unspec = SET_SRC (pattern);
gcc_assert (GET_CODE (unspec) == UNSPEC);
switch (index)
{
case UNSPEC_STACK_ALIGN:
/* ??? We should set the CFA = (SP & ~7). At this point we haven't
put anything on the stack, so hopefully it won't matter.
CFA = SP will be correct after alignment. */
dwarf2out_reg_save_reg (label, stack_pointer_rtx,
SET_DEST (pattern));
break;
default:
gcc_unreachable ();
}
}
/* Output unwind directives for the start/end of a function. */
void
......
gcc/config/arm/arm.md
......@@ -94,8 +94,6 @@
UNSPEC_TLS ; A symbol that has been treated properly for TLS usage.
UNSPEC_PIC_LABEL ; A label used for PIC access that does not appear in the
; instruction stream.
UNSPEC_STACK_ALIGN ; Doubleword aligned stack pointer. Used to
; generate correct unwind information.
UNSPEC_PIC_OFFSET ; A symbolic 12-bit OFFSET that has been treated
; correctly for PIC usage.
UNSPEC_GOTSYM_OFF ; The offset of the start of the GOT from a
......
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