26 lines
702 B
Systemverilog
26 lines
702 B
Systemverilog
/* CSE141L
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possible lookup table for PC target
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leverage a few-bit pointer to a wider number
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Lookup table acts like a function: here Target = f(Addr);
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in general, Output = f(Input); lots of potential applications
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*/
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module Immediate_LUT #(PC_width = 10)(
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input [ 2:0] addr,
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output logic[PC_width-1:0] datOut
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);
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always_comb begin
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datOut = 'h001; // default to 1 (or PC+1 for relative)
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case(addr)
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2'b00: datOut = 'hfc; // -4, i.e., move back 16 lines of machine code
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2'b01: datOut = 'h03;
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2'b10: datOut = 'h07;
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endcase
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end
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endmodule
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// 3fc = 1111111100 -4
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// PC 0000001000 8
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// 0000000100 4
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