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Date: Fri, 21 Mar 2014 23:35:12 +0000
From: Stuart Brady <sdb@zubnet.me.uk>
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Subject: Re: [Qemu-devel] [PATCH 02/14] tcg: Add INDEX_op_trunc_i32
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To: qemu-devel@nongnu.org

On Mon, Mar 17, 2014 at 11:37:44AM -0700, Richard Henderson wrote:
> diff --git a/tcg/README b/tcg/README
> index f178212..160cbe8 100644
> --- a/tcg/README
> +++ b/tcg/README
> @@ -306,6 +306,11 @@ This operation would be equivalent to
>  
>    dest = (t1 & ~0x0f00) | ((t2 << 8) & 0x0f00)
>  
> +* trunc_i32 t0, t1, pos
> +
> +For 64-bit hosts only, right shift the 64-bit input T1 by POS and
> +truncate to 32-bit output T0.  Depending on the host, this may be
> +a simple mov/shift, or may require additional canonicalization.

Surely trunc_rshift_i64_i32, which is used elsewhere in this patch?

... or trunc_shr_i64_i32 as we use 'shr' for the existing shift-right op.

Cheers,
Stuart