Pragmas Syntax - 2020.2 English

Allocation

• The Syntax of the allocation pragma must be followed..

  Example:

  #pragma HLS allocation instances=mul limit=1 operation // Invalid format
  #pragma HLS allocation operation instances=mul limit=1 // Valid format
  #pragma HLS allocation instances=foo limit=2 function // Invalid format
  #pragma HLS allocation function instances=foo limit=2 // Valid format
  
  IMPORTANT: If the referenced function/operation is not located after "allocation", it will be ignored with a warning message:
  WARNING: [HLS 207-1604] unexpected pragma argument 'instances', expects function/operation.

• When Using Template functions, the allocation pragma syntax has to be adhered as shown below.

  template <typename DT>
  void foo(DT a, DT b){
  }
  
  
  
  Invalid syntax 
  // Below is invalid
  #pragma HLS ALLOCATION function instances = foo
  Valid syntax 
  
  // Below is valid
  #pragma HLS ALLOCATION function instances = foo<DT>