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From: Richard Henderson <rth@twiddle.net>
To: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] tcg: try sti when moving a constant into a dead memory temp
Date: Tue, 20 Sep 2016 13:41:08 -0700	[thread overview]
Message-ID: <98a4be9e-8e90-b2b9-9b66-ab673c94e2c6@twiddle.net> (raw)
In-Reply-To: <1473945360-13663-1-git-send-email-pbonzini@redhat.com>

On 09/15/2016 06:16 AM, Paolo Bonzini wrote:
> This comes from free from unifying tcg_reg_alloc_mov and
> tcg_reg_alloc_movi's handling of TEMP_VAL_CONST.  It triggers
> often on moves to cc_dst, such as the following translation
> of "sub $0x3c,%esp":
> 
>   before:                          after:
>   subl   $0x3c,%ebp                subl   $0x3c,%ebp
>   movl   %ebp,0x10(%r14)           movl   %ebp,0x10(%r14)
>   movl   $0x3c,%ebx                movl   $0x3c,0x2c(%r14)
>   movl   %ebx,0x2c(%r14)

What's the input here?  From just this snippet it looks as if we should have
converted both of them to an immediate store.


r~

  reply	other threads:[~2016-09-20 20:41 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-15 13:16 [Qemu-devel] [PATCH] tcg: try sti when moving a constant into a dead memory temp Paolo Bonzini
2016-09-20 20:41 ` Richard Henderson [this message]
2016-09-21 13:37   ` Paolo Bonzini
2016-09-22 21:09 ` Richard Henderson

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