Skip to content

Add debug emit docs #12411

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
KevinRansom merged 7 commits into from
Nov 17, 2021
Merged

Add debug emit docs #12411

Changes from 1 commit
Commits
Show all changes
7 commits
Select commit Hold shift + click to select a range
83823ee
add debug emit docs
dsyme Nov 16, 2021
b5a2e0d
add debug emit docs
dsyme Nov 16, 2021
14da032
add debug emit docs
dsyme Nov 16, 2021
412fb3e
add debug emit docs
dsyme Nov 16, 2021
c8a71a2
add debug emit docs
dsyme Nov 16, 2021
c9b8fd7
add debug emit docs
dsyme Nov 16, 2021
f6c854c
add debug emit docs
dsyme Nov 16, 2021
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Prev Previous commit
Next Next commit
add debug emit docs
  • Loading branch information
@dsyme
dsyme committed Nov 16, 2021
commit c9b8fd79e71c7d97ad7b6d5ac54885aecf03d436
55 changes: 27 additions & 28 deletions docs/debug-emit.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -325,17 +325,17 @@ These all get `CompilerGeneratedAttribute`, and `DebuggerNonUserCodeAttribute`,

### Generated closures for lambdas

The codegen involved in closures is as follows:

| Source | Construct | Debug Points | Attributes | Notes |
|:----------------|:------------------|:-------------|:-------------|:------|
| (fun x -> ...) | Closure class | | | |
| | `.ctor` method | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/ilx/EraseClosures.fs#L584) | CompilerGenerated, DebuggerNonUserCode | |
| | `Invoke` method | from body of closure | | |
| generic local defn | Closure class | | | |
| | `.ctor` method | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/ilx/EraseClosures.fs#L486) | CompilerGenerated, DebuggerNonUserCode | |
| | `Specialize` method | from body of closure | | |
| Intermediate closure classes | | See [here](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/ilx/EraseClosures.fs#L459) and [here](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/ilx/EraseClosures.fs#L543). | CompilerGenerated, DebuggerNonUserCode | These are for long curried closures `fun a b c d e f -> ...`. |
The debug codegen involved in closures is as follows:

| Source | Construct | Debug Points | Attributes |
|:----------------|:------------------|:-------------|:-------------|
| (fun x -> ...) | Closure class | | |
| | `.ctor` method | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/ilx/EraseClosures.fs#L584) | CompilerGenerated, DebuggerNonUserCode |
| | `Invoke` method | from body of closure | |
| generic local defn | Closure class | | |
| | `.ctor` method | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/ilx/EraseClosures.fs#L486) | CompilerGenerated, DebuggerNonUserCode |
| | `Specialize` method | from body of closure | |
| Intermediate closure classes | For long curried closures `fun a b c d e f -> ...`. | See [here](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/ilx/EraseClosures.fs#L459) and [here](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/ilx/EraseClosures.fs#L543). | CompilerGenerated, DebuggerNonUserCode |

> TODO: generating debug points for the intermediate closures appears wrong, this is being assessed at time of writing

Expand All @@ -347,19 +347,19 @@ Sequence expressions generate class implementations which resemble closures.

The debug points recovered for the generated state machine code for `seq { ... }` is covered up above. The other codegen is as follows:

| Source | Construct | Debug Points | Attributes | Notes |
|:----------------|:------------------|:-------------|:-------------|:------|
| seq { ... } | State machine class | | "Closure" | |
| | `.ctor` method | none? | [none?](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5150) | |
| | `GetFreshEnumerator` | [none?](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5108) | CompilerGenerated, DebuggerNonUserCode | |
| | `LastGenerated` | [none?](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5146-L5148) | CompilerGenerated, DebuggerNonUserCode | |
| | `Close` | [none?](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5124-L5127) | none!? | |
| | `get_CheckClose` | [none?](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5130-L5133) | none!? | |
| | `GenerateNext` | from desugaring, and [here](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5136-L5143) | none | |
| Source | Construct | Debug Points | Attributes |
|:----------------|:------------------|:-------------|:-------------|
| seq { ... } | State machine class | | "Closure" |
| | `.ctor` method | none | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5150) |
| | `GetFreshEnumerator` | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5108) | CompilerGenerated, DebuggerNonUserCode |
| | `LastGenerated` | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5146-L5148) | CompilerGenerated, DebuggerNonUserCode |
| | `Close` | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5124-L5127) | none |
| | `get_CheckClose` | [none](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5130-L5133) | none |
| | `GenerateNext` | from desugaring, and [here](https://github.com/dotnet/fsharp/blob/db2c9da8d1e76d11217d6da53a64253fd0df0246/src/fsharp/IlxGen.fs#L5136-L5143) | none |

> NOTE: it appears from the code that extraneous debug points are not being generated, which is good, though should be checked

> TODO: we should likely be generating attributes for the "Close" and other methods
> TODO: we should likely be generating attributes for the `Close` and `get_CheckClose` and `.ctor` methods

> TODO: we should also consider emitting `ExcludeFromCodeCoverageAttribute`, being assessed at time of writing

Expand All @@ -372,7 +372,7 @@ The debug points recovered for the generated state machine code for `seq { ... }
| Source | Construct | Debug Points | Attributes | Notes |
|:----------------|:------------------|:-------------|:-------------|:------|
| task { ... } | State machine struct | | "Closure" | |
| | `.ctor` method | none? | none? | |
| | `.ctor` method | none | none | |
| | TBD | | | |

> TODO: we should be generating attributes for some of these
Expand All @@ -381,23 +381,23 @@ The debug points recovered for the generated state machine code for `seq { ... }

### Generated code for delegate constructions `Func<int,int>(fun x y -> x + y)`

TBD. A closure class is generated.
A closure class is generated.

### Generated code for constant-sized array and list expressions

TBD. These are not generally problematic for debug.
These are not generally problematic for debug.

### Generated code for large constant arrays

TBD
These are not generally problematic for debug.

### Generated code for pattern matching

TBD
The implementation is a little gnarly and complicated and has historically had glitches.

### Generated code for conditionals and boolean logic

See for example [this proposed feature improvement](https://github.com/dotnet/fsharp/issues/11980)
Generally straight-forward. See for example [this proposed feature improvement](https://github.com/dotnet/fsharp/issues/11980)

### Capture and closures

Expand Down Expand Up @@ -484,4 +484,3 @@ These are major holes in the F# experience and should be implemented.
### Missing debug emit for F# Interactive

For F# Interactive [we do not currently emit debug information for script code](https://github.com/dotnet/fsharp/issues/5457). This is because of a missing piece of functionality in the Reflection.Emit APIs, and means we have to change our approach to emitting code fragments in F# Interactive to no longer use dynamic assemblies.