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Subject: Re: [Qemu-devel] [PATCH 7/7] tcg-i386: Perform tail call to
	qemu_ret_ld*_mmu
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To: Aurelien Jarno <aurelien@aurel32.net>
Cc: qemu-devel@nongnu.org

On 08/29/2013 10:06 AM, Aurelien Jarno wrote:
> On Tue, Aug 27, 2013 at 02:46:31PM -0700, Richard Henderson wrote:
>> This does require the fast path always load to the function return
>> value register, but apparently the loaded value usually needs to be
>> spilled back to its memory slot anyway so the change in register
>> does not really change much.
> 
> My suggestion was to only do that for the store, not for the load.

Ah, ok.  Fair enough.

Shall I include the tail-call for store only if it saves code space,
due any possible concern for call-return stack?

I'm thinking here of PPC, which is 100% space neutral on this,
exchanging one B for one MTLR in order to implement the tail call.


r~