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Re: patch to improve i386 epilogue (version 5)


On Fri, Oct 09, 1998 at 01:52:25AM -0400, John Wehle wrote:
> Fri Oct  9 01:10:08 EDT 1998  John Wehle  (john@feith.com)
> 
> 	* flow.c: Update comment.
> 	(life_analysis_1): Set current_function_stack_pointer_is_stable.
> 	* function.c: Define it.
> 	(init_function_start): Initialize it.
> 	* output.h: Declare it.
> 	* i386.c (ix86_epilogue): Optimize the restoring
> 	of the stack pointer.

Am I missing something, or are you working way too hard for this?

/* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
   the stack pointer does not matter.  The value is tested only in
   functions that have frame pointers.
   No definition is equivalent to always zero.  */
/* Note on the 386 it might be more efficient not to define this since 
   we have to restore it ourselves from the frame pointer, in order to
   use pop */

#define EXIT_IGNORE_STACK 1



r~


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