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Francisco Jerez authored
Currently the GLSL-to-TGSI translation pass assumes it can use floating point source modifiers on the UCMP instruction. See the bug report linked below for an example where an unrelated change in the GLSL built-in lowering code for atan2 (e9ffd128 ) caused the generation of floating-point ir_unop_neg instructions followed by ir_triop_csel, which is translated into UCMP with a negate modifier on back-ends with native integer support. Allowing floating-point source modifiers on an integer instruction seems like rather dubious design for a transport IR, since the same semantics could be represented as a sequence of MOV+UCMP instructions instead, but supposedly this matches the expectations of TGSI back-ends other than tgsi_exec, and the expectations of the DX10 API. I take no responsibility for future headaches caused by this inconsistency. Fixes a regression of piglit glsl-fs-tan-1 on softpipe introduced by the above-mentioned glsl front-end commit. Even though the commit that triggered the regression doesn't seem to have made it to any stable branches yet, this might be worth back-porting since I don't see any reason why the bug couldn't have been reproduced before that point. Suggested-by: Roland Scheidegger <sroland@vmware.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99817 Reviewed-by: Roland Scheidegger <sroland@vmware.com>
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