Managed Code Generation Utilities - mcgutils

This repo holds a collection of utilites used by the Managed CodeGen team to automate tasks when working on CoreCLR. Initial utilies are around producing diffs of codegen changes.

Summary

To prepare the tools for use, from the root of the cloned mcgutils repo, do the following:

1. Download required package dependencies: dotnet restore
   • NOTE: On Mac, you need to first use ulimit -n 2048 or the dotnet restore will fail.
2. Build and publish the tools: build.{cmd|sh} -f -p

This will create the following directories in the repo root:

1. bin - contains one directory for each built tool.
2. fx - contains a set of frameworks assemblies that can be used for asm diffs.

Add each tool subdirectory to your path so you can easily invoke them, e.g.:

set mcgutils=<path to root of mcgutils clone>
set PATH=%PATH%;%mcgutils%\bin\mcgdiff;%mcgutils%\bin\corediff;%mcgutils%\bin\analyze

For a more complete introduction look at the getting started guide.

mcgdiff

This is a general tool to produce diffs for compiled MSIL assemblies. The tool relies on a base and diff crossgen.exe as inputs, either by using a prebuilt base from the CI builds and a local experimental build, or building both a base and diff locally.

Sample help commandline:

    $ mcgdiff --help

    usage: mcgdiff [-b <arg>] [-d <arg>] [-o <arg>] [-t <arg>] [-f <arg>]
                   [-r] [-p <arg>] [--] <assembly>...
        -b, --base <arg>        The base compiler exe.
        -d, --diff <arg>        The diff compiler exe.
        -o, --output <arg>      The output path.
        -t, --tag <arg>         Name of root in output directory.  Allows
                                for many sets of output.
        -f, --file <arg>        Name of file to take list of assemblies
                                from. Both a file and assembly list can be
                                used.
        -r, --recursive         Scan directories recursively.
        -p, --platform <arg>    Path to platform assemblies
        <assembly>...           The list of assemblies or directories to
                                scan for assemblies.

corediff

Corediff is a tool specifically targeting CoreCLR. It has a prebaked list of interesting assemblies to use for generating assembly diffs and understands enough of the structure to make it more streamlined. Corediff uses mcgdiff under the covers to produce the diffs so for other projects a new utility could be produced that works in a similar way.

Sample help commandline:

    $ corediff --help

    usage: corediff [-b <arg>] [-d <arg>] [-o <arg>] [-t <arg>]
                    [--core_root <arg>] [--test_root <arg>]
        -b, --base <arg>      The base compiler exe.
        -d, --diff <arg>      The diff compiler exe.
        -o, --output <arg>    The output path.
        -t, --tag <arg>       Name of root in output directory.  Allows for
                              many sets of output.
        --core_root <arg>     Path to test CORE_ROOT.
        --test_root <arg>     Path to test tree

analyze

The analyze tool understand the format of the *.dasm files in a diff and can extract this data to produce a summary and/or dump the info to a unified data file (CSV, JSON) The common usage of the tool is to extract interesting diffs, if any, from a diff run as part of the development progresses.

Sample help commandline:

    $ analyze --help
    usage: analyze [-b <arg>] [-d <arg>] [-r] [-f] [-c <arg>] [-w]
                [--json <arg>] [--csv <arg>]

        -b, --base <arg>     Base file or directory.
        -d, --diff <arg>     Diff file or directory.
        -r, --recursive      Search directories recursively.
        -f, --full           Output full analysis to stdout (rather than a
                             summary).
        -c, --count <arg>    Count of files and methods (at most) to output
                             in the symmary. (count) improvements and
                             (count) regressions of each will be included.
                             (default 5)
        -w, --warn           Generate warning output for files/methods that
                             only exists in one dataset or the other (only
                             in base or only in diff).
        --json <arg>         Dump analysis data to specified file in JSON
                             format.
        --csv <arg>          Dump analysis data to specified file in CSV
                             format.

packages

This is a skeleton project that exists to pull down a predictable set of framework assemblies and publish them in the root in the subdirectory './fx'. Today this is set to the RC2 version of the NetCoreApp1.0 frameworks. When this package is installed via the build.{cmd|sh} script this set can be used on any supported platform for diffing. Note: The RC2 mscorlib.dll is removed, as this assembly should be updated from the selected base runtime that is under test for consistency. To add particular packages to the set you diff, add their dependencies to the project.json in this project and they will be pulled in and published in the standalone directory './fx'.