Re: RFA: ia64 prologue skipping patch

[Kevin Buettner <kevinb@redhat.com>]

On May 14,  7:47pm, J. Johnston wrote:
> Subject: RFA: ia64 prologue skipping patch
> 
> The attached patch revises the ia64 prologue skipping code.  It does a number of
> things:
> 
>    1. increases the number of instructions to look at in a prologue
>    2. allows looking in leaf functions
>    3. recognizes indirect input register references (one level only)
>    4. attempts to trust the lim_pc value
> 
> Number 1 was increased to handle some testsuite cases where the number of
> parameters was quite high (e.g. 9 parameters).  No tuning was involved.
> 
> Number 4 has the biggest effect.  The line table info is more accurate except
> in the case of optimized code.
> 
> Ok to commit?

Okay  (But fix the formatting of your ChangeLog entry - the lines are too
long.)

> 2003-05-14  Jeff Johnston  <jjohnstn@redhat.com>
> 
> 	* ia64-tdep.c: Increase max_skip_non_prologue_insns to 40.
> 	(examine_prologue): Support looking through leaf functions, knowing
> 	they start with mov r2,r12.  Support skipping over indirect stores of the input
> 	registers.  Upon hitting a non-nop branch instruction or predicated instruction,
> 	bail out by setting lim_pc to the current pc value in the loop.  At the end,
> 	if the lim_pc value is still beyond our calculated value and we have trust_limit set,
> 	use the lim_pc value.

Kevin