[Mesa-dev] [Bug 83573] [swrast] piglit fs-op-not-bool-using-if regression

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=83573

Kenneth Graunke <kenneth at whitecape.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |brianp at vmware.com,
                   |                            |maraeo at gmail.com

--- Comment #1 from Kenneth Graunke <kenneth at whitecape.org> ---
I thought Marek's patch (mesa: set UniformBooleanTrue = 1.0f by default) would
fix this, but it doesn't.  Using integer 1 works.

Setting DEBUG_PROG = 1 in prog_execute.c and making ADD print values in
hexadecimal, I see:

----false case----
ADD (3f800000 3f800000 3f800000 3f800000) = (80000000 80000000 80000000
80000000
) + (3f800000 3f800000 3f800000 3f800000)
ADD (1 1 1 1) = (-0 -0 -0 -0) + (1 1 1 1)

----true case----
ADD (ce7e0000 ce7e0000 ce7e0000 ce7e0000) = (ce7e0000 ce7e0000 ce7e0000
ce7e0000) + (3f800000 3f800000 3f800000 3f800000)
ADD (-1.06535e+09 -1.06535e+09 -1.06535e+09 -1.06535e+09) = (-1.06535e+09
-1.06535e+09 -1.06535e+09 -1.06535e+09) + (1 1 1 1)

So, it looks like we're seeing 1.0f = 3f800000 numerically converted to a float
somewhere (rather than bitcast).  0x3f800000 = 1065353216 = 1.06535322E9.  The
ADD negates op[0], giving -1.06535322E9 = 0xce7e0000.

I'm not sure where that's happening yet.

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