[gcc(refs/vendors/ARM/heads/CVE-2023-4039/gcc-9)] aarch64: Rename hard_fp_offset to bytes_above_hard_fp

[gcc(refs/vendors/ARM/heads/CVE-2023-4039/gcc-9)] aarch64: Rename hard_fp_offset to bytes_above_hard_fp

[Richard Sandiford]

https://gcc.gnu.org/g:16016465ff28a75f5e0540cbaeb4eb102fdc3230

commit 16016465ff28a75f5e0540cbaeb4eb102fdc3230
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Tue Jun 27 11:28:11 2023 +0100

    aarch64: Rename hard_fp_offset to bytes_above_hard_fp
    
    Similarly to the previous locals_offset patch, hard_fp_offset
    was described as:
    
      /* Offset from the base of the frame (incomming SP) to the
         hard_frame_pointer.  This value is always a multiple of
         STACK_BOUNDARY.  */
      poly_int64 hard_fp_offset;
    
    which again took an “upside-down” view: higher offsets meant lower
    addresses.  This patch renames the field to bytes_above_hard_fp instead.
    
    gcc/
            * config/aarch64/aarch64.h (aarch64_frame::hard_fp_offset): Rename
            to...
            (aarch64_frame::bytes_above_hard_fp): ...this.
            * config/aarch64/aarch64.c (aarch64_layout_frame)
            (aarch64_expand_prologue): Update accordingly.
            (aarch64_initial_elimination_offset): Likewise.

Diff:
---
 gcc/config/aarch64/aarch64.c | 21 +++++++++++----------
 gcc/config/aarch64/aarch64.h |  6 +++---
 2 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index dcaf491af428..2681e0c2bb90 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -4747,7 +4747,7 @@ aarch64_layout_frame (void)
   HOST_WIDE_INT varargs_and_saved_regs_size
     = offset + cfun->machine->frame.saved_varargs_size;
 
-  cfun->machine->frame.hard_fp_offset
+  cfun->machine->frame.bytes_above_hard_fp
     = aligned_upper_bound (varargs_and_saved_regs_size
 			   + get_frame_size (),
 			   STACK_BOUNDARY / BITS_PER_UNIT);
@@ -4756,7 +4756,7 @@ aarch64_layout_frame (void)
   gcc_assert (multiple_p (cfun->machine->frame.bytes_below_hard_fp,
 			  STACK_BOUNDARY / BITS_PER_UNIT));
   cfun->machine->frame.frame_size
-    = (cfun->machine->frame.hard_fp_offset
+    = (cfun->machine->frame.bytes_above_hard_fp
        + cfun->machine->frame.bytes_below_hard_fp);
 
   cfun->machine->frame.bytes_above_locals
@@ -4788,7 +4788,7 @@ aarch64_layout_frame (void)
   else if (known_lt (cfun->machine->frame.bytes_below_hard_fp
 		     + cfun->machine->frame.saved_regs_size, 512)
 	   && !(cfun->calls_alloca
-		&& known_lt (cfun->machine->frame.hard_fp_offset,
+		&& known_lt (cfun->machine->frame.bytes_above_hard_fp,
 			     max_push_offset)))
     {
       /* Frame with small area below the saved registers:
@@ -4797,14 +4797,14 @@ aarch64_layout_frame (void)
 	 stp reg3, reg4, [sp, bytes_below_hard_fp + 16]  */
       cfun->machine->frame.initial_adjust = cfun->machine->frame.frame_size;
       cfun->machine->frame.callee_offset
-	= cfun->machine->frame.frame_size - cfun->machine->frame.hard_fp_offset;
+	= cfun->machine->frame.frame_size - cfun->machine->frame.bytes_above_hard_fp;
     }
-  else if (cfun->machine->frame.hard_fp_offset.is_constant (&const_fp_offset)
+  else if (cfun->machine->frame.bytes_above_hard_fp.is_constant (&const_fp_offset)
 	   && const_fp_offset < max_push_offset)
     {
       /* Frame with large area below the saved registers, but with a
 	 small area above:
-	 stp reg1, reg2, [sp, -hard_fp_offset]!
+	 stp reg1, reg2, [sp, -bytes_above_hard_fp]!
 	 stp reg3, reg4, [sp, 16]
 	 sub sp, sp, bytes_below_hard_fp  */
       cfun->machine->frame.callee_adjust = const_fp_offset;
@@ -4814,12 +4814,13 @@ aarch64_layout_frame (void)
   else
     {
       /* General case:
-	 sub sp, sp, hard_fp_offset
+	 sub sp, sp, bytes_above_hard_fp
 	 stp x29, x30, [sp, 0]
 	 add x29, sp, 0
 	 stp reg3, reg4, [sp, 16]
 	 sub sp, sp, bytes_below_hard_fp  */
-      cfun->machine->frame.initial_adjust = cfun->machine->frame.hard_fp_offset;
+      cfun->machine->frame.initial_adjust
+	= cfun->machine->frame.bytes_above_hard_fp;
       cfun->machine->frame.final_adjust
 	= cfun->machine->frame.frame_size - cfun->machine->frame.initial_adjust;
     }
@@ -8563,10 +8564,10 @@ aarch64_initial_elimination_offset (unsigned from, unsigned to)
   if (to == HARD_FRAME_POINTER_REGNUM)
     {
       if (from == ARG_POINTER_REGNUM)
-	return cfun->machine->frame.hard_fp_offset;
+	return cfun->machine->frame.bytes_above_hard_fp;
 
       if (from == FRAME_POINTER_REGNUM)
-	return cfun->machine->frame.hard_fp_offset
+	return cfun->machine->frame.bytes_above_hard_fp
 	       - cfun->machine->frame.bytes_above_locals;
     }
 
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index a079a88b4f46..eab6da84a02e 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -724,10 +724,10 @@ struct GTY (()) aarch64_frame
      STACK_BOUNDARY.  */
   poly_int64 bytes_above_locals;
 
-  /* Offset from the base of the frame (incomming SP) to the
-     hard_frame_pointer.  This value is always a multiple of
+  /* The number of bytes between the hard_frame_pointer and the top of
+     the frame (the incomming SP).  This value is always a multiple of
      STACK_BOUNDARY.  */
-  poly_int64 hard_fp_offset;
+  poly_int64 bytes_above_hard_fp;
 
   /* The size of the frame.  This value is the offset from base of the
      frame (incomming SP) to the stack_pointer.  This value is always