GhidraSleighEditor makes developing and modifying Ghidra Sleigh processor modules much more enjoyable by providing a modern day context sensitive editor with syntax highlighting, navigation, context sensitive error notation, quick fixes, and more. The editor is built with the excellent XTEXT DSL framework within Eclipse.
The information provided in this document is effective as of Ghidra Sleigh Editor 1.0.0 and is subject to change with future releases.
GhidraSleighEditor is installed manually into Eclipse and should be installed by anyone interested in working with processor module sleigh specifications. The Sleigh Editor must be manually installed in Eclipse. In the future the extension may be installed automatically along with the GhidraDev Eclipse plugin when setting up Eclipse for Ghidra scripting and plugin development.
GhidraSleighEditor can be installed into an existing installation of Eclipse the same way most Eclipse plugins are installed. From Eclipse:
To build the Sleigh Editor, follow the instructions in ghidra/DevGuide.md to setup eclipse for development. Then follow the directions in ghidra/GhidraBuild/EclipsePlugins/GhidraSleighEditor/ghidra.xtext.sleigh.feature/build_README.txt.
GhidraSleighEditor can be uninstalled as follows from Eclipse:
GhidraSleighEditor can be upgraded the same way it was initially installed.
The Ghidra Sleigh Editor provides a variety of features one would expect in any modern IDE to make viewing, modifying, debugging, and creating Sleigh processor specifications as painless as possible. Once installed, any .sinc or .slaspec file that is edited will be brought up in the sleigh editor.
The editor provides the following capabilities:
Keywords, Tokens, Sub-constructor names, Comments, Instruction Formats, Strings, Variables, and more can be colorized to make the sliegh specification more readable. In the Window → Preferences → Sleigh preferences panel, the color and font style can be changed for any sleigh file tokens.
The structure of a sleigh file while fairly simple can lend itself to errors when using a straight text editor. The editor understands the syntax and all constructs of a sleigh file. Instead of waiting for the sleigh compiler to produce an error, many but not all syntax errors can be caught and displayed with a red error marker.
The editor validates the definition of variables including locals. Though legal in the sleigh compiler, it has been found that not declaring local variables leads to errors that are not be caught by the sleigh compiler. For example, assigning to a variable 'ro' when the actual register name is 'r0' may go unnoticed. All local variables must be defined with with the 'local' keyword or with an initial ':size'.
Warnings on duplicate names of tokens is marked in yellow. Complex matching patterns such as '!=' '<' '>' are warnings as well. Using comparison matching operators can cause the generated .sla file to be much larger than necessary. Comparison matching should really never be used on any tokens that are bigger than a few bits as the number of match cases generated will be large. Their use is unavoidable in some cases.
There are some artificial enforcements in the editor that, while valid sleigh syntax, cause the syntax to be unparsable. Because the sleigh Domain Specific Language (DSL) is a context sensitive grammer, as well as using define-like pre-processing expansion, the editor only allows define $() variables at certain locations where a single token would reside. The most common flagged error is embedding a connecting '&' in a define and then using it an a match pattern:
:MOV ax, bx is t1=1 $(BadDefine) {} is not allowed, and instead should be :MOV ax, bx is t1=1 & $(GoodDefine) {}.
Some simple syntax errors can be fixed quickly with QuickFix suggestions. Pressing Crtl-1 on an error will bring up available quick-fixes.
More quick-fixes may be added in the future. Please note quickfixes can be slow on large files such as the AARCH64.
There are many constructs in a sleigh file that, when hovered over, will display additional information. This is especially useful for tokens to get their size without having to navigate to the token field definition. More hovers will be added.
If you have edited a sleigh processor specification in a regular text editor, you will appreciate the forward and backward navigation supported on various variable name use and their associated definition. Navigation is supported on sub-constructor names, field token names, registers, macros names, local variables, define names, and user define pcodeop's.
Navigate by pressing <F3> on a variable, using the forward/backward navigation arrows, or my favorite the <-* that will navigate back to the last edit location.
Instead of keyword searching, the editor provides a find all uses of a variable. Each found use is listed in a search window with the text of the line where it is used displayed. Each found location can also be navigated to by double clicking on the found reference.
Use the editor popup menu Find References action.
The name of variables can be very important, and instead of doing a search and replace on a string, the editor can refactor a name and change all other uses of that name. The name is even changed in other .sinc and .slaspec files.
Use the editor popup menu Rename Element action.
Sleigh files can get large and messy during development. Instead of paying much attention to format, or trying to format by hand you can use the Source Format action. Common constructs are lined up, for example the token definitions will find the longest token and line up all other tokens and their definition. All sub-constructors of the same name will be lined up on the 'is' keyword, the match pattern, and the semantic definitions. All constructors 'is' keywords will be generally lined up based on the longest print peice for each constructor. Statements will also be indented consistently. Multi-line attach definitions will have each entry lined up. Formatting can be restricted to a selection of lines to stop formatting from entirely re-formatting carefully formatted files. Additional formatting may be added in the future, and the formatter may become more configurable in the future.
Use the editor popup menu Source → Format action.
1.0.0: Initial release in Ghidra 9.1