The Veryl team has published a new release of Veryl, 0.12.0. Veryl is a new hardware description language as an alternate to SystemVerilog.

The latest version of Veryl can be downloaded from release page.

Breaking Changes

Forbid continuous casting #887

Until Veryl 0.12.0, casting by as could be continuous, but it is forbidden by Veryl 0.12.0. If continuous casting is required, it can be achieved by inserting ().

// Syntax error
assign a = x as u32 as i32;
// OK
assign a = (x as u32) as i32;

Change symbol of clock domain annotation #883

Until Veryl 0.12.0, clock domain annotation used single quotation mark like 'x. Veryl 0.12.0 changes it to backtick mark like `x.

// Syntax error
var a: 'x clock;
// OK
var a: `x clock;

New Features

Expand inside operation #873

Some EDA tools doesn't support inside operation. For these tools, expand_inside_operation configuration of Veryl.toml can be used like below:

[build]
expand_inside_operation = true

If the configuration is enabled, inside operations in the generated SystemVerilog are expanded like below:

• Default

assign a = ((1 + 2 / 3) inside {0, 0..10, 1..=10});

• Expand

assign a = ((1 + 2 / 3) ==? 0) ||
           ((1 + 2 / 3) >= 0 && (1 + 2 / 3) < 10) ||
           ((1 + 2 / 3) >= 0 && (1 + 2 / 3) <= 10);

Waveform dump support through veryl test --wave #898

Waveform dump in integrated test is supported. If --wave option is specified at veryl test, [test name].vcd files are generated. The generation place is the same as generated SystemVerilog code by default. It can be configured through waveform_target in Veryl.toml.

[test]
waveform_target = {type = "directory", path = "[dst dir]"}

Cocotb support for integrated test #899

As the way of embed and language specifier, cocotb and py are supported now. If cocotb is specified, the embeded code are interpreted as cocotb code and executed through external Python3 environment. cocotb requires to specify the name of top module, so it should be specified through the second argument of #[test] attribute.

To use this feature, python3 environment in which cocotb 1.9.0 is installed is required.

#[test(test1, ModuleA)]
embed (cocotb) py{{{
import cocotb

@cocotb.test()
async def test(dut):
    dut.i_d.value = 0
}}}

Embed standard library into compiler #878

Standard library is embeded into Veryl compiler, and it can be used through std namespace. For example, std::fifo is FIFO module in standard library, and can be used without adding dependency like below. All list and documentation is https://std.veryl-lang.org.

module ModuleA {
    inst u: std::fifo (
        i_clk        : _,
        i_rst        : _,
        i_clear      : _,
        o_empty      : _,
        o_almost_full: _,
        o_full       : _,
        o_word_count : _,
        i_push       : _,
        i_data       : _,
        i_pop        : _,
        o_data       : _,
    );
}

The public API of standard library is not stable until Veryl 1.0. If there is any idea or suggestion, please open issue or pull request at https://github.com/veryl-lang/std.

Other Changes

Check out everything that changed in Release v0.12.0.