[gcc(refs/vendors/ARM/heads/CVE-2023-4039/gcc-10)] aarch64: Simplify top of frame allocation

[gcc(refs/vendors/ARM/heads/CVE-2023-4039/gcc-10)] aarch64: Simplify top of frame allocation

[Richard Sandiford]

https://gcc.gnu.org/g:ff7193c5313d736e20aa66c33abeaf102cc6c152

commit ff7193c5313d736e20aa66c33abeaf102cc6c152
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Fri Jun 16 17:44:39 2023 +0100

    aarch64: Simplify top of frame allocation
    
    After previous patches, it no longer really makes sense to allocate
    the top of the frame in terms of varargs_and_saved_regs_size and
    saved_regs_and_above.
    
    gcc/
            * config/aarch64/aarch64.c (aarch64_layout_frame): Simplify
            the allocation of the top of the frame.

Diff:
---
 gcc/config/aarch64/aarch64.c | 23 ++++++++---------------
 1 file changed, 8 insertions(+), 15 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 1ed335f54879..70542c6e13f5 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -7010,23 +7010,16 @@ aarch64_layout_frame (void)
 
   frame.saved_regs_size = offset - frame.bytes_below_saved_regs;
 
-  poly_int64 varargs_and_saved_regs_size
-    = frame.saved_regs_size + frame.saved_varargs_size;
-
-  poly_int64 saved_regs_and_above
-    = aligned_upper_bound (varargs_and_saved_regs_size
-			   + get_frame_size (),
-			   STACK_BOUNDARY / BITS_PER_UNIT);
-
-  frame.bytes_above_hard_fp
-    = saved_regs_and_above - frame.below_hard_fp_saved_regs_size;
+  offset += get_frame_size ();
+  offset = aligned_upper_bound (offset, STACK_BOUNDARY / BITS_PER_UNIT);
+  poly_int64 top_of_locals = offset;
 
-  /* Both these values are already aligned.  */
-  gcc_assert (multiple_p (frame.bytes_below_saved_regs,
-			  STACK_BOUNDARY / BITS_PER_UNIT));
-  frame.frame_size = saved_regs_and_above + frame.bytes_below_saved_regs;
+  offset += frame.saved_varargs_size;
+  gcc_assert (multiple_p (offset, STACK_BOUNDARY / BITS_PER_UNIT));
+  frame.frame_size = offset;
 
-  frame.bytes_above_locals = frame.saved_varargs_size;
+  frame.bytes_above_hard_fp = frame.frame_size - frame.bytes_below_hard_fp;
+  frame.bytes_above_locals = frame.frame_size - top_of_locals;
 
   frame.initial_adjust = 0;
   frame.final_adjust = 0;