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maksyuki
3b6a925a51
- Created documentation for , , , and modules, detailing their functionality, parameters, and usage examples. - Implemented a script to ensure required headings and content are present in documentation files. - Developed to generate and update documentation pages from SystemVerilog declarations, ensuring consistency and completeness.
70 lines
1.9 KiB
Markdown
70 lines
1.9 KiB
Markdown
# bit_count
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| Property | Value |
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| --- | --- |
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| Kind | `module` |
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| RTL source | [`rtl/base/bit_ops.sv`](../../../rtl/base/bit_ops.sv) |
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| Availability | Synthesizable RTL |
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## Summary
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Combinational population-count primitive.
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## Functional Behavior
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Combinational population-count primitive. It is a self-contained base primitive with the behavior and parameter checks implemented in the linked RTL source.
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## Suitable Applications
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Use as a structured building block for control, encoding, ECC, hashing, masking, replacement, or observability logic.
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## Parameters
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The declaration below is canonical; retain the RTL-enforced parameter range.
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| Parameter | Declaration |
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| --- | --- |
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| `WIDTH` | `parameter int WIDTH = 32` |
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| `COUNT_WIDTH` | `parameter int COUNT_WIDTH = $clog2(WIDTH + 1)` |
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## Interface Definition
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```systemverilog
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module bit_count #(
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parameter int WIDTH = 32,
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parameter int COUNT_WIDTH = $clog2(WIDTH + 1)
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) (
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input logic [ WIDTH-1:0] value_i,
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output logic [COUNT_WIDTH-1:0] count_o
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);
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```
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### Port Summary
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| Signal | Direction | Declaration |
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| --- | --- | --- |
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| `value_i` | `input` | `input logic [ WIDTH-1:0] value_i` |
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| `count_o` | `output` | `output logic [COUNT_WIDTH-1:0] count_o` |
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## Integration and Use
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Honor validity/error outputs and parameter constraints. Combinational cells do not provide timing isolation or CDC protection.
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```systemverilog
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bit_count #(
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.WIDTH(WIDTH),
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.COUNT_WIDTH(COUNT_WIDTH)
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) u_bit_count (
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.value_i(value_i),
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.count_o(count_o)
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);
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```
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## Dependencies and Verification
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The linked RTL source is the implementation authority and contains local assertions for unsupported
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parameter combinations. See [`docs/design.md`](../../design.md) for repository-wide CDC, reset,
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stream, and storage contracts, and [`docs/verification.md`](../../verification.md) for the
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verification matrix.
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