1  from amaranth import *
 2  from amaranth_types import ValueLike
 3  
 4  from coreblocks.params import GenParams
 5  
 6  __all__ = ["FrontendParams"]
 7  
 8  
 9  class FrontendParams:
10      def __init__(self, gen_params: GenParams):
11          self.gp = gen_params
12  
13      def fb_addr(self, pc: ValueLike) -> Value:
14          """Returns the fetch block address of a given PC."""
15          return Value.cast(pc)[self.gp.fetch_block_bytes_log :]
16  
17      def fb_instr_idx(self, pc: ValueLike) -> Value:
18          """Returns the index of an instruction in a fetch block for a given instruction PC."""
19          return Value.cast(pc)[self.gp.min_instr_width_bytes_log : self.gp.fetch_block_bytes_log]
20  
21      def pc_from_fb(self, fb_addr: ValueLike, fb_instr_idx: int | Value) -> Value:
22          """For a given fetch block address and an instruction index, returns the instruction's PC."""
23          if isinstance(fb_instr_idx, int):
24              fb_instr_idx = C(fb_instr_idx, self.gp.fetch_width_log)
25          assert len(fb_instr_idx) == self.gp.fetch_width_log
26          return Cat(C(0, self.gp.min_instr_width_bytes_log), fb_instr_idx, fb_addr)