Re: [Qemu-devel] [PATCH 10/17] tcg/optimize: do not remember garbage high bits for 32-bit ops

[Aurelien Jarno]

On 2015-08-17 12:38, Richard Henderson wrote:
> From: Aurelien Jarno <address@hidden>
> 
> Now that we have real size changing ops, we don't need to mark high
> bits of the destination as garbage. The goal of the optimizer is to
> predict the value of the temps (and not of the registers) and do
> simplifications when possible. The problem there is therefore not the
> fact that those bits are not counted as garbage, but that a size
> changing op is replaced by a move.
> 
> This patch is basically a revert of 24666baf, including the changes that
> have been made since then.
> 
> Cc: Richard Henderson <address@hidden>
> Signed-off-by: Aurelien Jarno <address@hidden>
> ---
>  tcg/optimize.c | 41 +++++++++++------------------------------
>  1 file changed, 11 insertions(+), 30 deletions(-)

Self NACK. This patch breaks things given !(def->flags & TCG_OPF_64BIT)
doesn't necessary means 32-bit result, at least in the case of the call
opcode.

I'll try to send an updated patch which handles that correctly in the
next days (and catch up on other QEMU things), I am currently busy with
other free software stuff.

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
address@hidden                 http://www.aurel32.net