i386: Use reference of struct ix86_frame to avoid copy

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

Tested on x86-64.

	* config/i386/i386.c (ix86_can_use_return_insn_p): Use reference
	of struct ix86_frame.
	(ix86_initial_elimination_offset): Likewise.
	(ix86_expand_split_stack_prologue): Likewise.

From-SVN: r254480

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b904b17b624fe4d2a594b968176d9d5417572c1e..9353fd3586dd266388d4561f28193008d643a589 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2017-11-06  H.J. Lu  <hongjiu.lu@intel.com>
+
+       * config/i386/i386.c (ix86_can_use_return_insn_p): Use reference
+       of struct ix86_frame.
+       (ix86_initial_elimination_offset): Likewise.
+       (ix86_expand_split_stack_prologue): Likewise.
+
 2017-11-06  Marc Glisse  <marc.glisse@inria.fr>
 
        * tree-vrp.h (enum value_range_type): Update stale comment.

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 0d5e2726a33cd19de0f801023831f0b595d2e1cb..1e2709d8aec4946ce3953a6437a1200c907c6f99 100644 (file)
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -10486,8 +10486,6 @@ symbolic_reference_mentioned_p (rtx op)
 bool
 ix86_can_use_return_insn_p (void)
 {
-  struct ix86_frame frame;
-
   if (ix86_function_naked (current_function_decl))
     return false;
 
@@ -10502,7 +10500,7 @@ ix86_can_use_return_insn_p (void)
   if (crtl->args.pops_args && crtl->args.size >= 32768)
     return 0;
 
-  frame = cfun->machine->frame;
+  struct ix86_frame &frame = cfun->machine->frame;
   return (frame.stack_pointer_offset == UNITS_PER_WORD
          && (frame.nregs + frame.nsseregs) == 0);
 }
@@ -10996,7 +10994,7 @@ ix86_can_eliminate (const int from, const int to)
 HOST_WIDE_INT
 ix86_initial_elimination_offset (int from, int to)
 {
-  struct ix86_frame frame = cfun->machine->frame;
+  struct ix86_frame &frame = cfun->machine->frame;
 
   if (from == ARG_POINTER_REGNUM && to == HARD_FRAME_POINTER_REGNUM)
     return frame.hard_frame_pointer_offset;
@@ -14334,7 +14332,6 @@ ix86_split_stack_guard (void)
 void
 ix86_expand_split_stack_prologue (void)
 {
-  struct ix86_frame frame;
   HOST_WIDE_INT allocate;
   unsigned HOST_WIDE_INT args_size;
   rtx_code_label *label;
@@ -14346,7 +14343,7 @@ ix86_expand_split_stack_prologue (void)
   gcc_assert (flag_split_stack && reload_completed);
 
   ix86_finalize_stack_frame_flags ();
-  frame = cfun->machine->frame;
+  struct ix86_frame &frame = cfun->machine->frame;
   allocate = frame.stack_pointer_offset - INCOMING_FRAME_SP_OFFSET;
 
   /* This is the label we will branch to if we have enough stack