We are subtract an extra "cfun->machine->frame.fp_lr_offset" which is
wrong, but the AARCH64_ROUND_UP below happen to compensate that, thus hiding
this bug.
The offset from FRAME_POINTER_REGNUM to STACK_POINTER_REGNUM is
exactly the sum of outgoing argument size, callee saved reg size
and local variable size. Just as what commented in aarch64 target file:
+-------------------------------+ <-- arg_pointer_rtx
| |
| callee-allocated save area |
| for register varargs |
| |
+-------------------------------+ <-- frame_pointer_rtx (A)
| |
| local variables |
| |
+-------------------------------+
| padding0 | \
+-------------------------------+ |
| | |
| | |
| callee-saved registers | | frame.saved_regs_size
| | |
+-------------------------------+ |
| LR' | |
+-------------------------------+ |
| FP' | /
P +-------------------------------+ <-- hard_frame_pointer_rtx
| dynamic allocation |
+-------------------------------+
| |
| outgoing stack arguments |
| |
+-------------------------------+ <-- stack_pointer_rtx (B)
When alloca invoked, frame pointer is always required, no elimination
from FRAME_POINTER_REGNUM to STACK_POINTER_REGNUM.
OK for stage 1?
2014-04-22 Renlin <renlin...@arm.com>
2014-04-22 Jiong Wang <jiong.w...@arm.com>
gcc/
* config/aarch64/aarch64.h (aarch64_frame): Delete "fp_lr_offset".
* config/aarch64/aarch64.c (aarch64_layout_frame): Likewise.
* config/aarch64/aarch64.c (aarch64_initial_elimination_offset): Likewise.
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index ebd58c0..ee49bbe 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -1719,8 +1719,6 @@ aarch64_layout_frame (void)
if (reload_completed && cfun->machine->frame.laid_out)
return;
- cfun->machine->frame.fp_lr_offset = 0;
-
/* First mark all the registers that really need to be saved... */
for (regno = R0_REGNUM; regno <= R30_REGNUM; regno++)
cfun->machine->frame.reg_offset[regno] = -1;
@@ -1770,14 +1768,12 @@ aarch64_layout_frame (void)
{
cfun->machine->frame.reg_offset[R29_REGNUM] = offset;
offset += UNITS_PER_WORD;
- cfun->machine->frame.fp_lr_offset = UNITS_PER_WORD;
}
if (cfun->machine->frame.reg_offset[R30_REGNUM] != -1)
{
cfun->machine->frame.reg_offset[R30_REGNUM] = offset;
offset += UNITS_PER_WORD;
- cfun->machine->frame.fp_lr_offset += UNITS_PER_WORD;
}
cfun->machine->frame.padding0 =
@@ -4183,8 +4179,7 @@ aarch64_initial_elimination_offset (unsigned from, unsigned to)
{
HOST_WIDE_INT elim = crtl->outgoing_args_size
+ cfun->machine->frame.saved_regs_size
- + get_frame_size ()
- - cfun->machine->frame.fp_lr_offset;
+ + get_frame_size ();
elim = AARCH64_ROUND_UP (elim, STACK_BOUNDARY / BITS_PER_UNIT);
return elim;
}
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index 1f71ee5..aa38f9f 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -520,7 +520,6 @@ struct GTY (()) aarch64_frame
been saved. */
HOST_WIDE_INT padding0;
HOST_WIDE_INT hardfp_offset; /* HARD_FRAME_POINTER_REGNUM */
- HOST_WIDE_INT fp_lr_offset; /* Space needed for saving fp and/or lr */
bool laid_out;
};
