https://bugs.freedesktop.org/show_bug.cgi?id=93447
--- Comment #3 from Ilia Mirkin imirkin@alum.mit.edu --- (In reply to Grazvydas Ignotas from comment #2)
I believe this bug can also be triggered by radeonsi though, as it also calls radeon_llvm_emit_prepare_cube_coords(). When target == TGSI_TEXTURE_CUBE and opcode == TGSI_OPCODE_TXF, si_shader.c will take and use garbage value from that function.
You can't texelFetch() on a samplerCube.