SDF to VHDL generic matching

An SDF file contains delay and timing constraint data for cell instances in the design. The annotator must locate the cell instances and the placeholders (VHDL generics) for the timing data. Each type of SDF timing construct is mapped to the name of a generic as specified by the VITAL modeling specification. The annotator locates the generic and updates it with the timing value from the SDF file. It is an error if the annotator fails to find the cell instance or the named generic. The following are examples of SDF constructs and their associated generic names:

SDF construct	Matching VHDL generic name
(IOPATH a y (3))	tpd_a_y
(IOPATH (posedge clk) q (1) (2))	tpd_clk_q_posedge
(INTERCONNECT u1/y u2/a (5))	tipd_a
(SETUP d (posedge clk) (5))	tsetup_d_clk_noedge_posedge
(HOLD (negedge d) (posedge clk) (5))	thold_d_clk_negedge_posedge
(SETUPHOLD d clk (5) (5))	tsetup_d_clk & thold_d_clk
(WIDTH (COND (reset==1'b0) clk) (5))	tpw_clk_reset_eq_0

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