Vivado HLS: Is it Xilinx specific?
According to the Xilinx End User License agreement, section 4.a titled "Special Use Restrictions"...


  
  Restrictions
  
  (a) Special Use Restrictions. No right is granted hereunder to use 
  the Software or any Bitstream
  generated by use of the Software to program or develop designs for
  non-Xilinx Devices... 
  
  
  [source: Xilinx EULA (March 14, 2014)]


So I would say, no, you cannot use Xilinx Vivado HLS to even attempt to generate code for another vendor's device.