Add support for generating pointers to funclets, and calling funclets by index by davidwrighton · Pull Request #128222 · dotnet/runtime

davidwrighton · 2026-05-14T18:49:46Z

Note

This PR was created with assistance from GitHub Copilot.

Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this
Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods
Pseudo instruction i32_const_funcletptr is known to work, I have not explicitly tested pseudo-instruction call_funclet
Updates our current logic to setup the call chain with meaningful function pointers

… by index - Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this - Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods - psuedo instruction i32_const_funcletptr is known to work, I have not explicitly tested psuedo-instruction call_funclet

Copilot

Pull request overview

Adds JIT/object-writer plumbing for emitting WASM relocations that point at funclets rather than just the primary function symbol. The funclet is identified by an addend on a normal function-index / table-index relocation against the parent method's code symbol; the WasmObjectWriter is updated to honor that addend so a future change can assign sequential indices to funclets emitted alongside their parent method. A new helper, instruction format, and pseudo-instruction (i32_const_funcletptr, plus an untested call_funclet) are introduced, and codegenwasm.cpp now stores the real (0) funclet id into the frame instead of the previous 0xBBBB placeholder.

Changes:

New IF_FUNCLETPTR / IF_FUNCLETIDX formats and INS_i32_const_funcletptr / INS_call_funclet pseudo-instructions, with sizing/emit/disasm support.
New emitter::emitFuncletAddressConstant helper, used by genAllocLclFrame to store a real funclet id in the frame; funclet relocs are emitted via emitRecordRelocationWithAddlDelta carrying the funclet id as the addend.
WasmObjectWriter.ResolveRelocations now adds the in-place addend to the resolved symbol index for WASM_TABLE_INDEX_* and WASM_FUNCTION_INDEX_LEB relocs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs	Include reloc addend when writing resolved function/table indices, enabling funclet offsets from the parent method symbol.
src/coreclr/jit/instrswasm.h	Add `call_funclet` and `i32_const_funcletptr` pseudo-instruction entries.
src/coreclr/jit/emitwasm.h	Declare `emitFuncletAddressConstant` and `emitOutputConstantFunclet`.
src/coreclr/jit/emitwasm.cpp	Implement funclet address constant emission, sizing, output, and disasm; plus a small null-`emitCurIG` guard in `IF_CODE_SIZE` disasm.
src/coreclr/jit/emitfmtswasm.h	Add `IF_FUNCLETPTR` and `IF_FUNCLETIDX` instruction formats.
src/coreclr/jit/codegenwasm.cpp	Replace the `0xBBBB` placeholder stored in fp[0] with a real funclet-id reloc via the new helper.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

adamperlin

This looks good to me. I'm glad we can re-use the existing reloc addend functionality here.

dotnet-policy-service · 2026-05-14T22:01:09Z

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

davidwrighton · 2026-05-18T17:34:03Z

/ba-g known infra timeouts

> [!NOTE] > This PR was created with assistance from Github Copilot This PR adds handling to the Wasm Object Writer to extract funclets attached to a compiled method as separate Wasm functions. To do this, an `INodeWithFunclets` interface was added for ReadyToRun and NativeAOT so that we can generically access EHInfo and FrameInfo fields attached to nodes which represent managed method definitions. We lay funclets out sequentially in the object file and they are added to the Wasm table contiguously. This is required by #128222 and lets us grab the funclet index using an offset from the index of the method it is attached to, i.e., funclet `i` for method M is at `table_index(M) + i`. Follow up on #127773 and other Wasm EH work. --------- Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

davidwrighton · 2026-05-14T18:49:46Z

Note

This PR was created with assistance from GitHub Copilot.

Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this
Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods
Pseudo instruction i32_const_funcletptr is known to work, I have not explicitly tested pseudo-instruction call_funclet
Updates our current logic to setup the call chain with meaningful function pointers

… by index - Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this - Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods - psuedo instruction i32_const_funcletptr is known to work, I have not explicitly tested psuedo-instruction call_funclet

Copilot

Pull request overview

Adds JIT/object-writer plumbing for emitting WASM relocations that point at funclets rather than just the primary function symbol. The funclet is identified by an addend on a normal function-index / table-index relocation against the parent method's code symbol; the WasmObjectWriter is updated to honor that addend so a future change can assign sequential indices to funclets emitted alongside their parent method. A new helper, instruction format, and pseudo-instruction (i32_const_funcletptr, plus an untested call_funclet) are introduced, and codegenwasm.cpp now stores the real (0) funclet id into the frame instead of the previous 0xBBBB placeholder.

Changes:

New IF_FUNCLETPTR / IF_FUNCLETIDX formats and INS_i32_const_funcletptr / INS_call_funclet pseudo-instructions, with sizing/emit/disasm support.
New emitter::emitFuncletAddressConstant helper, used by genAllocLclFrame to store a real funclet id in the frame; funclet relocs are emitted via emitRecordRelocationWithAddlDelta carrying the funclet id as the addend.
WasmObjectWriter.ResolveRelocations now adds the in-place addend to the resolved symbol index for WASM_TABLE_INDEX_* and WASM_FUNCTION_INDEX_LEB relocs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs	Include reloc addend when writing resolved function/table indices, enabling funclet offsets from the parent method symbol.
src/coreclr/jit/instrswasm.h	Add `call_funclet` and `i32_const_funcletptr` pseudo-instruction entries.
src/coreclr/jit/emitwasm.h	Declare `emitFuncletAddressConstant` and `emitOutputConstantFunclet`.
src/coreclr/jit/emitwasm.cpp	Implement funclet address constant emission, sizing, output, and disasm; plus a small null-`emitCurIG` guard in `IF_CODE_SIZE` disasm.
src/coreclr/jit/emitfmtswasm.h	Add `IF_FUNCLETPTR` and `IF_FUNCLETIDX` instruction formats.
src/coreclr/jit/codegenwasm.cpp	Replace the `0xBBBB` placeholder stored in fp[0] with a real funclet-id reloc via the new helper.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

adamperlin

This looks good to me. I'm glad we can re-use the existing reloc addend functionality here.

dotnet-policy-service · 2026-05-14T22:01:09Z

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

davidwrighton · 2026-05-18T17:34:03Z

/ba-g known infra timeouts

> [!NOTE] > This PR was created with assistance from Github Copilot This PR adds handling to the Wasm Object Writer to extract funclets attached to a compiled method as separate Wasm functions. To do this, an `INodeWithFunclets` interface was added for ReadyToRun and NativeAOT so that we can generically access EHInfo and FrameInfo fields attached to nodes which represent managed method definitions. We lay funclets out sequentially in the object file and they are added to the Wasm table contiguously. This is required by #128222 and lets us grab the funclet index using an offset from the index of the method it is attached to, i.e., funclet `i` for method M is at `table_index(M) + i`. Follow up on #127773 and other Wasm EH work. --------- Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

davidwrighton · 2026-05-14T18:49:46Z

Note

This PR was created with assistance from GitHub Copilot.

Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this
Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods
Pseudo instruction i32_const_funcletptr is known to work, I have not explicitly tested pseudo-instruction call_funclet
Updates our current logic to setup the call chain with meaningful function pointers

… by index - Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this - Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods - psuedo instruction i32_const_funcletptr is known to work, I have not explicitly tested psuedo-instruction call_funclet

Copilot

Pull request overview

Adds JIT/object-writer plumbing for emitting WASM relocations that point at funclets rather than just the primary function symbol. The funclet is identified by an addend on a normal function-index / table-index relocation against the parent method's code symbol; the WasmObjectWriter is updated to honor that addend so a future change can assign sequential indices to funclets emitted alongside their parent method. A new helper, instruction format, and pseudo-instruction (i32_const_funcletptr, plus an untested call_funclet) are introduced, and codegenwasm.cpp now stores the real (0) funclet id into the frame instead of the previous 0xBBBB placeholder.

Changes:

New IF_FUNCLETPTR / IF_FUNCLETIDX formats and INS_i32_const_funcletptr / INS_call_funclet pseudo-instructions, with sizing/emit/disasm support.
New emitter::emitFuncletAddressConstant helper, used by genAllocLclFrame to store a real funclet id in the frame; funclet relocs are emitted via emitRecordRelocationWithAddlDelta carrying the funclet id as the addend.
WasmObjectWriter.ResolveRelocations now adds the in-place addend to the resolved symbol index for WASM_TABLE_INDEX_* and WASM_FUNCTION_INDEX_LEB relocs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs	Include reloc addend when writing resolved function/table indices, enabling funclet offsets from the parent method symbol.
src/coreclr/jit/instrswasm.h	Add `call_funclet` and `i32_const_funcletptr` pseudo-instruction entries.
src/coreclr/jit/emitwasm.h	Declare `emitFuncletAddressConstant` and `emitOutputConstantFunclet`.
src/coreclr/jit/emitwasm.cpp	Implement funclet address constant emission, sizing, output, and disasm; plus a small null-`emitCurIG` guard in `IF_CODE_SIZE` disasm.
src/coreclr/jit/emitfmtswasm.h	Add `IF_FUNCLETPTR` and `IF_FUNCLETIDX` instruction formats.
src/coreclr/jit/codegenwasm.cpp	Replace the `0xBBBB` placeholder stored in fp[0] with a real funclet-id reloc via the new helper.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

adamperlin

This looks good to me. I'm glad we can re-use the existing reloc addend functionality here.

dotnet-policy-service · 2026-05-14T22:01:09Z

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

davidwrighton · 2026-05-18T17:34:03Z

/ba-g known infra timeouts

> [!NOTE] > This PR was created with assistance from Github Copilot This PR adds handling to the Wasm Object Writer to extract funclets attached to a compiled method as separate Wasm functions. To do this, an `INodeWithFunclets` interface was added for ReadyToRun and NativeAOT so that we can generically access EHInfo and FrameInfo fields attached to nodes which represent managed method definitions. We lay funclets out sequentially in the object file and they are added to the Wasm table contiguously. This is required by #128222 and lets us grab the funclet index using an offset from the index of the method it is attached to, i.e., funclet `i` for method M is at `table_index(M) + i`. Follow up on #127773 and other Wasm EH work. --------- Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

davidwrighton · 2026-05-14T18:49:46Z

Note

This PR was created with assistance from GitHub Copilot.

Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this
Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods
Pseudo instruction i32_const_funcletptr is known to work, I have not explicitly tested pseudo-instruction call_funclet
Updates our current logic to setup the call chain with meaningful function pointers

… by index - Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this - Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods - psuedo instruction i32_const_funcletptr is known to work, I have not explicitly tested psuedo-instruction call_funclet

Copilot

Pull request overview

Adds JIT/object-writer plumbing for emitting WASM relocations that point at funclets rather than just the primary function symbol. The funclet is identified by an addend on a normal function-index / table-index relocation against the parent method's code symbol; the WasmObjectWriter is updated to honor that addend so a future change can assign sequential indices to funclets emitted alongside their parent method. A new helper, instruction format, and pseudo-instruction (i32_const_funcletptr, plus an untested call_funclet) are introduced, and codegenwasm.cpp now stores the real (0) funclet id into the frame instead of the previous 0xBBBB placeholder.

Changes:

New IF_FUNCLETPTR / IF_FUNCLETIDX formats and INS_i32_const_funcletptr / INS_call_funclet pseudo-instructions, with sizing/emit/disasm support.
New emitter::emitFuncletAddressConstant helper, used by genAllocLclFrame to store a real funclet id in the frame; funclet relocs are emitted via emitRecordRelocationWithAddlDelta carrying the funclet id as the addend.
WasmObjectWriter.ResolveRelocations now adds the in-place addend to the resolved symbol index for WASM_TABLE_INDEX_* and WASM_FUNCTION_INDEX_LEB relocs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs	Include reloc addend when writing resolved function/table indices, enabling funclet offsets from the parent method symbol.
src/coreclr/jit/instrswasm.h	Add `call_funclet` and `i32_const_funcletptr` pseudo-instruction entries.
src/coreclr/jit/emitwasm.h	Declare `emitFuncletAddressConstant` and `emitOutputConstantFunclet`.
src/coreclr/jit/emitwasm.cpp	Implement funclet address constant emission, sizing, output, and disasm; plus a small null-`emitCurIG` guard in `IF_CODE_SIZE` disasm.
src/coreclr/jit/emitfmtswasm.h	Add `IF_FUNCLETPTR` and `IF_FUNCLETIDX` instruction formats.
src/coreclr/jit/codegenwasm.cpp	Replace the `0xBBBB` placeholder stored in fp[0] with a real funclet-id reloc via the new helper.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

adamperlin

This looks good to me. I'm glad we can re-use the existing reloc addend functionality here.

dotnet-policy-service · 2026-05-14T22:01:09Z

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

davidwrighton · 2026-05-18T17:34:03Z

/ba-g known infra timeouts

> [!NOTE] > This PR was created with assistance from Github Copilot This PR adds handling to the Wasm Object Writer to extract funclets attached to a compiled method as separate Wasm functions. To do this, an `INodeWithFunclets` interface was added for ReadyToRun and NativeAOT so that we can generically access EHInfo and FrameInfo fields attached to nodes which represent managed method definitions. We lay funclets out sequentially in the object file and they are added to the Wasm table contiguously. This is required by #128222 and lets us grab the funclet index using an offset from the index of the method it is attached to, i.e., funclet `i` for method M is at `table_index(M) + i`. Follow up on #127773 and other Wasm EH work. --------- Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

davidwrighton · 2026-05-14T18:49:46Z

Note

This PR was created with assistance from GitHub Copilot.

Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this
Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods
Pseudo instruction i32_const_funcletptr is known to work, I have not explicitly tested pseudo-instruction call_funclet
Updates our current logic to setup the call chain with meaningful function pointers

… by index - Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this - Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods - psuedo instruction i32_const_funcletptr is known to work, I have not explicitly tested psuedo-instruction call_funclet

Copilot

Pull request overview

Adds JIT/object-writer plumbing for emitting WASM relocations that point at funclets rather than just the primary function symbol. The funclet is identified by an addend on a normal function-index / table-index relocation against the parent method's code symbol; the WasmObjectWriter is updated to honor that addend so a future change can assign sequential indices to funclets emitted alongside their parent method. A new helper, instruction format, and pseudo-instruction (i32_const_funcletptr, plus an untested call_funclet) are introduced, and codegenwasm.cpp now stores the real (0) funclet id into the frame instead of the previous 0xBBBB placeholder.

Changes:

New IF_FUNCLETPTR / IF_FUNCLETIDX formats and INS_i32_const_funcletptr / INS_call_funclet pseudo-instructions, with sizing/emit/disasm support.
New emitter::emitFuncletAddressConstant helper, used by genAllocLclFrame to store a real funclet id in the frame; funclet relocs are emitted via emitRecordRelocationWithAddlDelta carrying the funclet id as the addend.
WasmObjectWriter.ResolveRelocations now adds the in-place addend to the resolved symbol index for WASM_TABLE_INDEX_* and WASM_FUNCTION_INDEX_LEB relocs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs	Include reloc addend when writing resolved function/table indices, enabling funclet offsets from the parent method symbol.
src/coreclr/jit/instrswasm.h	Add `call_funclet` and `i32_const_funcletptr` pseudo-instruction entries.
src/coreclr/jit/emitwasm.h	Declare `emitFuncletAddressConstant` and `emitOutputConstantFunclet`.
src/coreclr/jit/emitwasm.cpp	Implement funclet address constant emission, sizing, output, and disasm; plus a small null-`emitCurIG` guard in `IF_CODE_SIZE` disasm.
src/coreclr/jit/emitfmtswasm.h	Add `IF_FUNCLETPTR` and `IF_FUNCLETIDX` instruction formats.
src/coreclr/jit/codegenwasm.cpp	Replace the `0xBBBB` placeholder stored in fp[0] with a real funclet-id reloc via the new helper.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

adamperlin

This looks good to me. I'm glad we can re-use the existing reloc addend functionality here.

dotnet-policy-service · 2026-05-14T22:01:09Z

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

davidwrighton · 2026-05-18T17:34:03Z

/ba-g known infra timeouts

> [!NOTE] > This PR was created with assistance from Github Copilot This PR adds handling to the Wasm Object Writer to extract funclets attached to a compiled method as separate Wasm functions. To do this, an `INodeWithFunclets` interface was added for ReadyToRun and NativeAOT so that we can generically access EHInfo and FrameInfo fields attached to nodes which represent managed method definitions. We lay funclets out sequentially in the object file and they are added to the Wasm table contiguously. This is required by #128222 and lets us grab the funclet index using an offset from the index of the method it is attached to, i.e., funclet `i` for method M is at `table_index(M) + i`. Follow up on #127773 and other Wasm EH work. --------- Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

davidwrighton · 2026-05-14T18:49:46Z

Note

This PR was created with assistance from GitHub Copilot.

Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this
Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods
Pseudo instruction i32_const_funcletptr is known to work, I have not explicitly tested pseudo-instruction call_funclet
Updates our current logic to setup the call chain with meaningful function pointers

… by index - Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this - Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods - psuedo instruction i32_const_funcletptr is known to work, I have not explicitly tested psuedo-instruction call_funclet

Copilot

Pull request overview

Adds JIT/object-writer plumbing for emitting WASM relocations that point at funclets rather than just the primary function symbol. The funclet is identified by an addend on a normal function-index / table-index relocation against the parent method's code symbol; the WasmObjectWriter is updated to honor that addend so a future change can assign sequential indices to funclets emitted alongside their parent method. A new helper, instruction format, and pseudo-instruction (i32_const_funcletptr, plus an untested call_funclet) are introduced, and codegenwasm.cpp now stores the real (0) funclet id into the frame instead of the previous 0xBBBB placeholder.

Changes:

New IF_FUNCLETPTR / IF_FUNCLETIDX formats and INS_i32_const_funcletptr / INS_call_funclet pseudo-instructions, with sizing/emit/disasm support.
New emitter::emitFuncletAddressConstant helper, used by genAllocLclFrame to store a real funclet id in the frame; funclet relocs are emitted via emitRecordRelocationWithAddlDelta carrying the funclet id as the addend.
WasmObjectWriter.ResolveRelocations now adds the in-place addend to the resolved symbol index for WASM_TABLE_INDEX_* and WASM_FUNCTION_INDEX_LEB relocs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs	Include reloc addend when writing resolved function/table indices, enabling funclet offsets from the parent method symbol.
src/coreclr/jit/instrswasm.h	Add `call_funclet` and `i32_const_funcletptr` pseudo-instruction entries.
src/coreclr/jit/emitwasm.h	Declare `emitFuncletAddressConstant` and `emitOutputConstantFunclet`.
src/coreclr/jit/emitwasm.cpp	Implement funclet address constant emission, sizing, output, and disasm; plus a small null-`emitCurIG` guard in `IF_CODE_SIZE` disasm.
src/coreclr/jit/emitfmtswasm.h	Add `IF_FUNCLETPTR` and `IF_FUNCLETIDX` instruction formats.
src/coreclr/jit/codegenwasm.cpp	Replace the `0xBBBB` placeholder stored in fp[0] with a real funclet-id reloc via the new helper.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

adamperlin

This looks good to me. I'm glad we can re-use the existing reloc addend functionality here.

dotnet-policy-service · 2026-05-14T22:01:09Z

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

davidwrighton · 2026-05-18T17:34:03Z

/ba-g known infra timeouts

> [!NOTE] > This PR was created with assistance from Github Copilot This PR adds handling to the Wasm Object Writer to extract funclets attached to a compiled method as separate Wasm functions. To do this, an `INodeWithFunclets` interface was added for ReadyToRun and NativeAOT so that we can generically access EHInfo and FrameInfo fields attached to nodes which represent managed method definitions. We lay funclets out sequentially in the object file and they are added to the Wasm table contiguously. This is required by #128222 and lets us grab the funclet index using an offset from the index of the method it is attached to, i.e., funclet `i` for method M is at `table_index(M) + i`. Follow up on #127773 and other Wasm EH work. --------- Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

davidwrighton · 2026-05-14T18:49:46Z

Note

This PR was created with assistance from GitHub Copilot.

Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this
Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods
Pseudo instruction i32_const_funcletptr is known to work, I have not explicitly tested pseudo-instruction call_funclet
Updates our current logic to setup the call chain with meaningful function pointers

… by index - Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this - Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods - psuedo instruction i32_const_funcletptr is known to work, I have not explicitly tested psuedo-instruction call_funclet

Copilot

Pull request overview

Adds JIT/object-writer plumbing for emitting WASM relocations that point at funclets rather than just the primary function symbol. The funclet is identified by an addend on a normal function-index / table-index relocation against the parent method's code symbol; the WasmObjectWriter is updated to honor that addend so a future change can assign sequential indices to funclets emitted alongside their parent method. A new helper, instruction format, and pseudo-instruction (i32_const_funcletptr, plus an untested call_funclet) are introduced, and codegenwasm.cpp now stores the real (0) funclet id into the frame instead of the previous 0xBBBB placeholder.

Changes:

New IF_FUNCLETPTR / IF_FUNCLETIDX formats and INS_i32_const_funcletptr / INS_call_funclet pseudo-instructions, with sizing/emit/disasm support.
New emitter::emitFuncletAddressConstant helper, used by genAllocLclFrame to store a real funclet id in the frame; funclet relocs are emitted via emitRecordRelocationWithAddlDelta carrying the funclet id as the addend.
WasmObjectWriter.ResolveRelocations now adds the in-place addend to the resolved symbol index for WASM_TABLE_INDEX_* and WASM_FUNCTION_INDEX_LEB relocs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs	Include reloc addend when writing resolved function/table indices, enabling funclet offsets from the parent method symbol.
src/coreclr/jit/instrswasm.h	Add `call_funclet` and `i32_const_funcletptr` pseudo-instruction entries.
src/coreclr/jit/emitwasm.h	Declare `emitFuncletAddressConstant` and `emitOutputConstantFunclet`.
src/coreclr/jit/emitwasm.cpp	Implement funclet address constant emission, sizing, output, and disasm; plus a small null-`emitCurIG` guard in `IF_CODE_SIZE` disasm.
src/coreclr/jit/emitfmtswasm.h	Add `IF_FUNCLETPTR` and `IF_FUNCLETIDX` instruction formats.
src/coreclr/jit/codegenwasm.cpp	Replace the `0xBBBB` placeholder stored in fp[0] with a real funclet-id reloc via the new helper.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

adamperlin

This looks good to me. I'm glad we can re-use the existing reloc addend functionality here.

dotnet-policy-service · 2026-05-14T22:01:09Z

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

davidwrighton · 2026-05-18T17:34:03Z

/ba-g known infra timeouts

> [!NOTE] > This PR was created with assistance from Github Copilot This PR adds handling to the Wasm Object Writer to extract funclets attached to a compiled method as separate Wasm functions. To do this, an `INodeWithFunclets` interface was added for ReadyToRun and NativeAOT so that we can generically access EHInfo and FrameInfo fields attached to nodes which represent managed method definitions. We lay funclets out sequentially in the object file and they are added to the Wasm table contiguously. This is required by #128222 and lets us grab the funclet index using an offset from the index of the method it is attached to, i.e., funclet `i` for method M is at `table_index(M) + i`. Follow up on #127773 and other Wasm EH work. --------- Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

davidwrighton · 2026-05-14T18:49:46Z

Note

This PR was created with assistance from GitHub Copilot.

Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this
Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods
Pseudo instruction i32_const_funcletptr is known to work, I have not explicitly tested pseudo-instruction call_funclet
Updates our current logic to setup the call chain with meaningful function pointers

… by index - Take advantage of relocation addend behavior, and pre-existing reloc logic to allow this - Requires some followon work in the WasmObjectWriter to emit the funclets along with the primary method and adjust the function indices for the primary methods - psuedo instruction i32_const_funcletptr is known to work, I have not explicitly tested psuedo-instruction call_funclet

Copilot

Pull request overview

Adds JIT/object-writer plumbing for emitting WASM relocations that point at funclets rather than just the primary function symbol. The funclet is identified by an addend on a normal function-index / table-index relocation against the parent method's code symbol; the WasmObjectWriter is updated to honor that addend so a future change can assign sequential indices to funclets emitted alongside their parent method. A new helper, instruction format, and pseudo-instruction (i32_const_funcletptr, plus an untested call_funclet) are introduced, and codegenwasm.cpp now stores the real (0) funclet id into the frame instead of the previous 0xBBBB placeholder.

Changes:

New IF_FUNCLETPTR / IF_FUNCLETIDX formats and INS_i32_const_funcletptr / INS_call_funclet pseudo-instructions, with sizing/emit/disasm support.
New emitter::emitFuncletAddressConstant helper, used by genAllocLclFrame to store a real funclet id in the frame; funclet relocs are emitted via emitRecordRelocationWithAddlDelta carrying the funclet id as the addend.
WasmObjectWriter.ResolveRelocations now adds the in-place addend to the resolved symbol index for WASM_TABLE_INDEX_* and WASM_FUNCTION_INDEX_LEB relocs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs	Include reloc addend when writing resolved function/table indices, enabling funclet offsets from the parent method symbol.
src/coreclr/jit/instrswasm.h	Add `call_funclet` and `i32_const_funcletptr` pseudo-instruction entries.
src/coreclr/jit/emitwasm.h	Declare `emitFuncletAddressConstant` and `emitOutputConstantFunclet`.
src/coreclr/jit/emitwasm.cpp	Implement funclet address constant emission, sizing, output, and disasm; plus a small null-`emitCurIG` guard in `IF_CODE_SIZE` disasm.
src/coreclr/jit/emitfmtswasm.h	Add `IF_FUNCLETPTR` and `IF_FUNCLETIDX` instruction formats.
src/coreclr/jit/codegenwasm.cpp	Replace the `0xBBBB` placeholder stored in fp[0] with a real funclet-id reloc via the new helper.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

adamperlin

This looks good to me. I'm glad we can re-use the existing reloc addend functionality here.

dotnet-policy-service · 2026-05-14T22:01:09Z

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

Copilot

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

davidwrighton · 2026-05-18T17:34:03Z

/ba-g known infra timeouts

> [!NOTE] > This PR was created with assistance from Github Copilot This PR adds handling to the Wasm Object Writer to extract funclets attached to a compiled method as separate Wasm functions. To do this, an `INodeWithFunclets` interface was added for ReadyToRun and NativeAOT so that we can generically access EHInfo and FrameInfo fields attached to nodes which represent managed method definitions. We lay funclets out sequentially in the object file and they are added to the Wasm table contiguously. This is required by #128222 and lets us grab the funclet index using an offset from the index of the method it is attached to, i.e., funclet `i` for method M is at `table_index(M) + i`. Follow up on #127773 and other Wasm EH work. --------- Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

CopilotAI review requested due to automatic review settings May 14, 2026 18:49

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github-actionsBot added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label May 14, 2026

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davidwrighton requested review from AndyAyersMS and adamperlin May 14, 2026 18:51

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davidwrighton added 2 commits May 14, 2026 12:12

Code review feedback
3151fbc

Remove change better done in another PR
e7d0ffd

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AndyAyersMS approved these changes May 14, 2026
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Merge branch 'main' into funclet_relocs_in_jit
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build-analysisBot mentioned this pull request May 17, 2026
[wasm] Tests failing with DirectoryNotFoundException trying to load test data #128293
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davidwrighton merged commit e00aafd into dotnet:mainMay 18, 2026
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dotnet-maestroBot mentioned this pull request May 19, 2026
[main] Source code updates from dotnet/runtime dotnet/dotnet#6681
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adamperlin mentioned this pull request May 29, 2026
crossgen2: Extract funclets in WasmObjectWriter #128736
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