SVLangserver

A language server for systemverilog that has been tested to work with coc.nvim, VSCode, Sublime Text 4 and emacs

Features

• Auto completion (no need for ctags or other such mechanisms)
• Go to symbol in document
• Go to symbol in workspace folder (indexed modules/interfaces/packages)
• Go to definition (works for module/interface/package names and for ports too!)
• Hover over help
• Signature help
• Fast indexing
• Verilator/Icarus linting on the fly
• Report hierarchy of a module
• Code snippets for many common blocks
• Code formatting with verible-verilog-format
• Elaborate syntax highlighting (for VSCode)

Versions

The code has been tested to work with below tool versions

• vim 8.2
  • coc.nvim 0.0.80-0b5130ea38
• VSCode 1.52.0
• Sublime Text Build 4126
• emacs 29.0.50
  • lsp-mode lsp-mode-20220328.1429
• Neovim 0.7.0
• Verilator 4.110
• Icarus Verilog Compiler 10.2
• Verible v0.0-1114-ged89c1b

Installation

• For coc.nvim
  • npm install -g @imc-trading/svlangserver
  • Update .vim/coc-settings.json
• For VSCode
  • Install the extension from the marketplace.
  • Update the settings
• For Sublime Text 3
  • Install the systemverilog package in sublime text
  • npm install -g @imc-trading/svlangserver
  • Update the LSP settings (Preferences -> Package Settings -> LSP -> settings) and the sublime-project files
• For emacs
  • Install lsp-mode
  • npm install -g @imc-trading/svlangserver
  • Update .emacs/init.el
• For neovim
  • Install nvim-lspconfig
  • npm install -g @imc-trading/svlangserver
  • Add following setting in your init.lua

  require'lspconfig'.svlangserver.setup{}

  • Update .nvim/lspconfig.json

To get the snippets, git clone this repo and copy the snippets directory wherever applicable

For installing from source (not applicable for VSCode)

• git clone https://github.com/imc-trading/svlangserver.git
• cd svlangserver && npm install
  • Update the settings with the correct command (e.g. /git/repo/path/svlangserver/bin/main.js)

NOTE: This has been tested with npm version 6.14.13 and node version 14.17.1

Settings

• systemverilog.includeIndexing: Array, Globs defining files to be indexed
• systemverilog.libraryIndexing: Array, Globs defining library files to be added to linting. It's useful when module name is not equal to filename.
• systemverilog.excludeIndexing: Array, Exclude files from indexing based on glob
• systemverilog.linter: String, Select linter
  • Default: 'verilator'
• systemverilog.launchConfiguration: String, Command to run for launching linting
  • Default: verilator --sv --lint-only --Wall
  • If not in path, replace verilator with the appropriate command
• systemverilog.lintOnUnsaved: Boolean, Lint even unsaved files
  • Default: true
• systemverilog.defines: Array, Defines for the project. Used by the language server as well as linting
  • Default: empty
• systemverilog.formatCommand: String, verible-verilog-format command for code formatting
  • Default: verible-verilog-format
  • If not in path, replace verible-verilog-format with the appropriate command
• systemverilog.disableCompletionProvider: Boolean, Disable auto completion provided by the language server
  • Default: false
• systemverilog.disableHoverProvider: Boolean, Disable hover over help provided by the language server
  • Default: false
• systemverilog.disableSignatureHelpProvider: Boolean, Disable signature help provided by the language server
  • Default: false
• systemverilog.disableLinting: Boolean, Disable linting
  • Default: false
• Example coc.nvim settings file

  {
      "languageserver": {
          "svlangserver": {
              "command": "svlangserver",
              "filetypes": ["systemverilog"],
              "settings": {
                  "systemverilog.includeIndexing": ["**/*.{sv,svh}"],
                  "systemverilog.excludeIndexing": ["test/**/*.sv*"],
                  "systemverilog.defines" : [],
                  "systemverilog.launchConfiguration": "/tools/verilator -sv -Wall --lint-only",
                  "systemverilog.formatCommand": "/tools/verible-verilog-format"
              }
          }
      }
  }

  For project specific settings this file should be at <WORKSPACE PATH>/.vim/coc-settings.json
• Example coc.nvim settings file (for windows)

  {
      "languageserver": {
          "svlangserver": {
              "module": "/usr/lib/node_modules/@imc-trading/svlangserver/bin/main.js",
              "args": ["--node-ipc"],
              "filetypes": ["systemverilog"],
              "settings": {
                  "systemverilog.includeIndexing": ["**/*.{sv,svh}"],
                  "systemverilog.excludeIndexing": ["test/**/*.sv*"],
                  "systemverilog.defines" : [],
                  "systemverilog.launchConfiguration": "/tools/verilator -sv -Wall --lint-only",
                  "systemverilog.formatCommand": "/tools/verible-verilog-format"
              }
          }
      }
  }

  For project specific settings this file should be at <WORKSPACE PATH>\.vim\coc-settings.json
• Example vscode settings file

  {
      "systemverilog.includeIndexing": ["**/*.{sv,svh}"],
      "systemverilog.excludeIndexing": ["test/**/*.sv*"],
      "systemverilog.defines" : [],
      "systemverilog.launchConfiguration": "/tools/verilator -sv -Wall --lint-only",
      "systemverilog.formatCommand": "/tools/verible-verilog-format"
  }

  For project specific settings this file should be at <WORKSPACE PATH>/.vscode/settings.json
• Example Sublime Text 3 settings files
  • The global LSP settings file: LSP.sublime-settings

    {
        "clients": {
            "svlangserver": {
                "enabled": true,
                "command": ["svlangserver"],
                "languageId": "systemverilog",
                "scopes": ["source.systemverilog"],
                "syntaxes": ["Packages/SystemVerilog/SystemVerilog.sublime-syntax"],
                "settings": {
                    "systemverilog.disableHoverProvider": true,
                    "systemverilog.launchConfiguration": "/tools/verilator -sv --lint-only -Wall",
                    "systemverilog.formatCommand" : "/tools/verible-verilog-format"
                }
            }
        }
    }

  • The project specific settings go in <PROJECT>.sublime-project

    {
        "folders":
        [
            {
                "path": "."
            }
        ],
        "settings": {
            "LSP": {
                "svlangserver": {
                    "settings": {
                        "systemverilog.includeIndexing": [ "**/*.{sv,svh}", ],
                        "systemverilog.excludeIndexing": ["test/**/*.sv*"],
                        "systemverilog.defines": [],
                    }
                }
            }
        }
    }

• Example settings for emacs
  • Below content goes in .emacs or init.el

    (require 'lsp-verilog)
    
    (custom-set-variables
      '(lsp-clients-svlangserver-launchConfiguration "/tools/verilator -sv --lint-only -Wall")
      '(lsp-clients-svlangserver-formatCommand "/tools/verible-verilog-format"))
    
    (add-hook 'verilog-mode-hook #'lsp-deferred)

  • The project specific settings go in .dir-locals.el

    ((verilog-mode (lsp-clients-svlangserver-workspace-additional-dirs . ("/some/lib/path"))
                   (lsp-clients-svlangserver-includeIndexing . ("src/**/*.{sv,svh}"))
                   (lsp-clients-svlangserver-excludeIndexing . ("src/test/**/*.{sv,svh}"))))

• Example neovim settings file

  {
      "languageserver": {
          "svlangserver": {
              "command": "svlangserver",
              "filetypes": ["systemverilog"],
              "settings": {
                  "systemverilog.includeIndexing": ["**/*.{sv,svh}"],
                  "systemverilog.excludeIndexing": ["test/**/*.sv*"],
                  "systemverilog.defines" : [],
                  "systemverilog.launchConfiguration": "/tools/verilator -sv -Wall --lint-only",
                  "systemverilog.formatCommand": "/tools/verible-verilog-format"
              }
          }
      }
  }

  For project specific settings this file should be at <WORKSPACE PATH>/.nvim/lspconfig.json

Commands

• systemverilog.build_index: Instructs language server to rerun indexing
• systemverilog.report_hierarchy: Generates hierarchy for the given module

coc.nvim usage

• The commands should be executed using CocRequest function. An example vim command would be:

command! SvBuildIndex call CocRequest("svlangserver", 'workspace/executeCommand', {'command': 'systemverilog.build_index'})
command! -range SvReportHierarchy call CocRequest("svlangserver", 'workspace/executeCommand', {'command': 'systemverilog.report_hierarchy', 'arguments': [input('Module/interface: ', <range> == 0 ? "" : expand("<cword>"))]})

If the above SvReportHierarchy command is called with visual selection, then the module name is pre-filled with the selection. Also depending on the coc.nvim version, the generated rpt.json file might not have the focus and user will have to switch buffer manually.

VSCode usage

• Typing build index in the command palette should invoke the build index command.
• Typing get hierarchy in the command palette should invoke the report hierarchy command. If invoked with an active slection, the module name is pre-filled with the selection.

Sublime usage

• A sublime-commands file needs to be created with the below content

[
  {
    "caption": "SvLangserver Build Index",
    "command": "lsp_execute",
    "args": {
      "session_name": "svlangserver",
      "command_name": "systemverilog.build_index",
      "command_args": []
    }
  },
  {
    "caption": "Svlangserver Report Hierarchy",
    "command": "lsp_execute",
    "args": {
      "session_name": "svlangserver",
      "command_name": "systemverilog.report_hierarchy",
      "command_args": ["${selection}"]
    }
  }
]

This should make the commands available in the command palette. For the report hierarchy command, the module name should be selected before invoking the command.

Emacs usage

• lsp-clients-svlangserver-build-index command should rerun the indexing.
• lsp-clients-svlangserver-report-hierarchy command should do the job. If invoked with an active slection, the module name is pre-filled with the selection.

Neovim usage

• :SvlangserverBuildIndex command should rerun the indexing.
• :SvlangserverReportHierarchy command will generate hierarchy file of the word under the cursor in normal mode.

Troubleshooting

• Editor is not able to find language server binary.
  • Make sure the binary is in the system path as exposed to the editor. If the binary is installed in custom directory, expose that path to your editor
• Not getting any diagnostics
  • Make sure the launchConfiguration setting has been properly set to use verilator from the correct installation path
• Diagnostics show Cannot find file containing module 'module_name'
  • Make sure all submodules can be found by includeIndexing
  • If the issue still remains, it may due to different naming of module and file, or a file containing multiple modules. Make sure these files can be found by libraryIndexing.
• Check settings used by the language server
  • for coc.nvim: Use the command :CocCommand workspace.showOutput and then select svlangserver
  • for vscode: Check the SVLangServer output channel
  • for sublime: Open the command palette in the tools menu and select LSP: Toggle Log Panel
  • for emacs: Check the *lsp-log* buffer
  • for neovim: Add vim.lsp.set_log_level("info") in your init.lua then check ~/.cache/nvim/lsp.log

Known Issues

• Language server doesn't understand most verification specific concepts (e.g. classes).

Future

Rewrite parser to make it much more robust

Acknowledgements

Although most of the code is written from scratch, this VSCode-SystemVerilog extension was what I started with and developed on.

Release Notes

See the changelog for more details

0.4.1

• Support for Neovim client with nvim-lspconfig
• Updated settings for faster indexing
• Bug fixes

0.4.0

• Icarus as linting alternative
• Command for reporting hierarchy
• Improved hover over formatting
• Improved symbol resolution
• Bug fixes

0.3.5

• Improvements to auto-completion and jump to definition
• Bug fixes

0.3.4

• Bug fixes

0.3.3

• Updated instructions to use published packages

0.3.1

• Add support for Sublime LSP and Emacs

0.3.0

• Initial release