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Subject: Re: [Qemu-devel] [PATCH v2] sparc32 : Signed integer division
	overflow
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To: Olivier Danet <odanet@caramail.com>, qemu-devel <qemu-devel@nongnu.org>, Blue Swirl <blauwirbel@gmail.com>, Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

On 03/19/2014 03:29 PM, Olivier Danet wrote:
> +        if ((int32_t) x0 != x0) {
> +            x0 = x0 < 0 ? 0x80000000 : 0x7fffffff;
> +            overflow = 1;
> +        }

Actually, there's an existing bug here that we might as well fix.

  ## ... the 32-bit result is sign-extended to 64 bits and
  ## written into register R[rd].

That 0x80000000 is not going to promote properly to 64-bits.  We might as well
go ahead and use INT32_MIN and INT32_MAX here at the same time.



r~