[PATCH 3/3] GCC 7: i386: More use reference of struct ix86_frame to avoid copy

[H.J. Lu]

When there is no need to make a copy of ix86_frame, we can use reference
of struct ix86_frame to avoid copy.

        Backport from mainline
        * config/i386/i386.c (ix86_expand_prologue): Use reference of
        struct ix86_frame.
        (ix86_expand_epilogue): Likewise.
---
 gcc/config/i386/i386.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 397ef7cac26..986e6d79584 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -13667,7 +13667,6 @@ ix86_expand_prologue (void)
 {
   struct machine_function *m = cfun->machine;
   rtx insn, t;
-  struct ix86_frame frame;
   HOST_WIDE_INT allocate;
   bool int_registers_saved;
   bool sse_registers_saved;
@@ -13691,7 +13690,7 @@ ix86_expand_prologue (void)
   m->fs.sp_valid = true;
 
   ix86_compute_frame_layout ();
-  frame = m->frame;
+  struct ix86_frame &frame = cfun->machine->frame;
 
   if (!TARGET_64BIT && ix86_function_ms_hook_prologue (current_function_decl))
     {
@@ -14354,13 +14353,12 @@ ix86_expand_epilogue (int style)
 {
   struct machine_function *m = cfun->machine;
   struct machine_frame_state frame_state_save = m->fs;
-  struct ix86_frame frame;
   bool restore_regs_via_mov;
   bool using_drap;
 
   ix86_finalize_stack_realign_flags ();
   ix86_compute_frame_layout ();
-  frame = m->frame;
+  struct ix86_frame &frame = cfun->machine->frame;
 
   m->fs.sp_valid = (!frame_pointer_needed
                    || (crtl->sp_is_unchanging
-- 
2.14.3