[Wasm RyuJIT] Packed Simd Encodings - #128229

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adamperlin merged 25 commits into
dotnet:mainfrom
adamperlin:adamperlin/wasm-simd-encodings
May 22, 2026
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[Wasm RyuJIT] Packed Simd Encodings#128229
adamperlin merged 25 commits into
dotnet:mainfrom
adamperlin:adamperlin/wasm-simd-encodings

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This PR adds emitter support for the Wasm Packed Simd v128 extension, including new instruction formats and instrDesc definitions. It also enables basic emitter unit testing support for these SIMD instructions, since we are not yet utilizing these instructions in codegen and so we aren't exercising the encoding paths.

Adam Perlinand others added 6 commits May 8, 2026 16:10
Adam Perlin
Add Wasm packed SIMD instruction encodings to JIT emitter
53bb222
Add instruction definitions and emitter infrastructure for the WebAssembly
packed SIMD (128-bit) instruction set:
- Add ~200 INST2 entries in instrswasm.h for all SIMD opcodes (0xFD prefix)
- Add 4 new instruction formats: IF_V128_CONST, IF_LANE, IF_MEMARG_LANE,
IF_SHUFFLE in emitfmtswasm.h
- Add instrDesc subclasses in emit.h for SIMD-specific payloads:
instrDescV128Const, instrDescShuffle, instrDescLane, instrDescMemargLane
- Increase TARGET_WASM instruction bit-field to 9 bits (512 max) in emit.h
- Add emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) with size calculation and output encoding in emitwasm.cpp
- Declare new emit functions in emitwasm.h
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Add debug emitter unit tests for Wasm packed SIMD encodings
21f74bc
Add genWasmEmitterUnitTestsSimd() to exercise the new SIMD instruction
emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) and representative plain-opcode SIMD instructions.
Activated via DOTNET_JitEmitUnitTests=* and
DOTNET_JitEmitUnitTestsSections=simd (or all).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Merge branch 'main' of github.com:dotnet/runtime into adamperlin/wasm…
5e5de0f
…-simd-encodings
Adam Perlin
Add temp emitter unit test block to wasm control flow stack and set o…
93d4d06
…rdering number for appropriate branching
Adam Perlin
Use the same instrDesc for v128.const and v128.shuffle
f4c1844
Update emitDispIns to support new SIMD instructions
Properly emit block ... end in emitter unit tests for Wasm
Adam Perlin
Properly emit branch to skip over emitter unit test instructions, and…
917d763
… fix IF_MEMARG_LANE instruction format
CopilotAI review requested due to automatic review settings May 14, 2026 21:32
@github-actionsgithub-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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Pull request overview

This PR wires up emitter-level support for the WebAssembly Packed SIMD (v128 / 0xFD-prefix) instruction set in the experimental Wasm RyuJIT back end. It adds the full SIMD instruction table, new instrDesc shapes and insFormats for the encodings that don't fit existing categories (v128 immediate, lane index, memarg+lane), and a debug-only emitter unit test that exercises the new encoding paths since no real codegen consumes them yet.

Changes:

  • Add the SIMD opcode table (instrswasm.h) and new IF_V128 / IF_LANE / IF_MEMARG_LANE formats with corresponding instrDescV128Imm and instrDescMemargLane descriptor types.
  • Implement emitIns_V128Imm, emitIns_Lane, emitIns_MemargLane, plus matching size/encode/display paths in emitwasm.cpp, and expand _idIns to 9 bits on WASM to fit the larger instruction count.
  • Add genWasmEmitterUnitTestsSimd (DEBUG-only) and hook the Wasm simd test section into genEmitterUnitTests, including a Wasm-specific skip-label scheme using INS_block / INS_br.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.

Show a summary per file
FileDescription
src/coreclr/jit/instrswasm.hAdds full v128 SIMD instruction list with IF_OPCODE/IF_MEMARG/IF_V128/IF_LANE/IF_MEMARG_LANE formats and 0xFD prefix.
src/coreclr/jit/emitfmtswasm.hDefines the three new SIMD encoding formats.
src/coreclr/jit/emit.hWidens _idIns to 9 bits on Wasm; adds idIsV128Imm/idIsMemargLaneImm; declares instrDescV128Imm/instrDescMemargLane.
src/coreclr/jit/emitwasm.hDeclares new emit helpers and accessors for the SIMD descriptors.
src/coreclr/jit/emitwasm.cppImplements emit/size/output/display paths for the new formats; also disables IF_CODE_SIZE display with #if FALSE (unrelated to SIMD).
src/coreclr/jit/codegen.hDeclares genWasmEmitterUnitTestsSimd.
src/coreclr/jit/codegenwasm.cppAdds the SIMD emitter unit test with representative coverage across all new formats.
src/coreclr/jit/codegenlinear.cppRoutes the simd unit-test section on Wasm and uses block/br instead of a direct jump to skip over the tests.

Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/codegenwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.h
@adamperlin
Potential fix for pull request finding
98f0ffe
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.

Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/codegenwasm.cpp Outdated
Comment threadsrc/coreclr/jit/codegenlinear.cpp Outdated
Comment threadsrc/coreclr/jit/instrswasm.h
@am11am11 added the arch-wasm WebAssembly architecture label May 14, 2026
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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
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Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.

Comment threadsrc/coreclr/jit/codegenlinear.cpp Outdated
Comment threadsrc/coreclr/jit/codegenlinear.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.cpp
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LGTM, comments and copilot feedback aside

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Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.

Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/codegeninterface.h Outdated
Comment threadsrc/coreclr/jit/instr.cpp
@adamperlin
Potential fix for pull request finding
35b8b7c
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
CopilotAI review requested due to automatic review settings May 21, 2026 22:07
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Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.

Comment threadsrc/coreclr/jit/codegeninterface.h
Comment threadsrc/coreclr/jit/instr.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
Comment threadsrc/coreclr/jit/emitwasm.h
Comment threadsrc/coreclr/jit/codegenwasm.cpp
CopilotAI review requested due to automatic review settings May 21, 2026 22:29
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Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

Comment threadsrc/coreclr/jit/codegenlinear.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
CopilotAI review requested due to automatic review settings May 22, 2026 00:29
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Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.

Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp Outdated
@adamperlin
adamperlin merged commit 18c8c26 into dotnet:mainMay 22, 2026
137 of 139 checks passed
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adamperlin deleted the adamperlin/wasm-simd-encodings branch May 22, 2026 21:06
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
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}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

Skip to content
[Wasm RyuJIT] Packed Simd Encodings - #128229
Merged
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
May 22, 2026
Merged
[Wasm RyuJIT] Packed Simd Encodings#128229
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
Conversation
@adamperlin
@adamperlinadamperlin
commented
May 14, 2026

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This PR adds emitter support for the Wasm Packed Simd v128 extension, including new instruction formats and instrDesc definitions. It also enables basic emitter unit testing support for these SIMD instructions, since we are not yet utilizing these instructions in codegen and so we aren't exercising the encoding paths.
Adam Perlinand others
added 6 commits
May 8, 2026 16:10
Adam Perlin
Add Wasm packed SIMD instruction encodings to JIT emitter
53bb222
Add instruction definitions and emitter infrastructure for the WebAssembly
packed SIMD (128-bit) instruction set:
- Add ~200 INST2 entries in instrswasm.h for all SIMD opcodes (0xFD prefix)
- Add 4 new instruction formats: IF_V128_CONST, IF_LANE, IF_MEMARG_LANE,
IF_SHUFFLE in emitfmtswasm.h
- Add instrDesc subclasses in emit.h for SIMD-specific payloads:
instrDescV128Const, instrDescShuffle, instrDescLane, instrDescMemargLane
- Increase TARGET_WASM instruction bit-field to 9 bits (512 max) in emit.h
- Add emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) with size calculation and output encoding in emitwasm.cpp
- Declare new emit functions in emitwasm.h
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Add debug emitter unit tests for Wasm packed SIMD encodings
21f74bc
Add genWasmEmitterUnitTestsSimd() to exercise the new SIMD instruction
emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) and representative plain-opcode SIMD instructions.
Activated via DOTNET_JitEmitUnitTests=* and
DOTNET_JitEmitUnitTestsSections=simd (or all).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Merge branch 'main' of github.com:dotnet/runtime into adamperlin/wasm…
5e5de0f
…-simd-encodings
Adam Perlin
Add temp emitter unit test block to wasm control flow stack and set o…
93d4d06
…rdering number for appropriate branching
Adam Perlin
Use the same instrDesc for v128.const and v128.shuffle
f4c1844
Update emitDispIns to support new SIMD instructions
Properly emit block ... end in emitter unit tests for Wasm
Adam Perlin
Properly emit branch to skip over emitter unit test instructions, and…
917d763
… fix IF_MEMARG_LANE instruction format
CopilotAI
review requested due to automatic review settings
May 14, 2026 21:32
@github-actionsgithub-actionsBot
added
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area-CodeGen-coreclr
CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
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Pull request overview
This PR wires up emitter-level support for the WebAssembly Packed SIMD (v128 / 0xFD-prefix) instruction set in the experimental Wasm RyuJIT back end. It adds the full SIMD instruction table, new instrDesc shapes and insFormats for the encodings that don't fit existing categories (v128 immediate, lane index, memarg+lane), and a debug-only emitter unit test that exercises the new encoding paths since no real codegen consumes them yet.
Changes:
  • Add the SIMD opcode table (instrswasm.h) and new IF_V128 / IF_LANE / IF_MEMARG_LANE formats with corresponding instrDescV128Imm and instrDescMemargLane descriptor types.
  • Implement emitIns_V128Imm, emitIns_Lane, emitIns_MemargLane, plus matching size/encode/display paths in emitwasm.cpp, and expand _idIns to 9 bits on WASM to fit the larger instruction count.
  • Add genWasmEmitterUnitTestsSimd (DEBUG-only) and hook the Wasm simd test section into genEmitterUnitTests, including a Wasm-specific skip-label scheme using INS_block / INS_br.
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Show a summary per file
FileDescription
src/coreclr/jit/instrswasm.hAdds full v128 SIMD instruction list with IF_OPCODE/IF_MEMARG/IF_V128/IF_LANE/IF_MEMARG_LANE formats and 0xFD prefix.
src/coreclr/jit/emitfmtswasm.hDefines the three new SIMD encoding formats.
src/coreclr/jit/emit.hWidens _idIns to 9 bits on Wasm; adds idIsV128Imm/idIsMemargLaneImm; declares instrDescV128Imm/instrDescMemargLane.
src/coreclr/jit/emitwasm.hDeclares new emit helpers and accessors for the SIMD descriptors.
src/coreclr/jit/emitwasm.cppImplements emit/size/output/display paths for the new formats; also disables IF_CODE_SIZE display with #if FALSE (unrelated to SIMD).
src/coreclr/jit/codegen.hDeclares genWasmEmitterUnitTestsSimd.
src/coreclr/jit/codegenwasm.cppAdds the SIMD emitter unit test with representative coverage across all new formats.
src/coreclr/jit/codegenlinear.cppRoutes the simd unit-test section on Wasm and uses block/br instead of a direct jump to skip over the tests.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.h
@adamperlin
Potential fix for pull request finding
98f0ffe
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/instrswasm.h
@am11am11
added
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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara

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This was referenced May 15, 2026

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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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LGTM, comments and copilot feedback aside
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/codegeninterface.h
Outdated

Comment threadsrc/coreclr/jit/instr.cpp
@adamperlin
Potential fix for pull request finding
35b8b7c
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegeninterface.h
Comment threadsrc/coreclr/jit/instr.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.h
Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

@adamperlin
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merged commit 18c8c26
into
dotnet:mainMay 22, 2026

137 of 139 checks passed

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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
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[Wasm RyuJIT] Packed Simd Encodings - #128229
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adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
May 22, 2026
Merged
[Wasm RyuJIT] Packed Simd Encodings#128229
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
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This PR adds emitter support for the Wasm Packed Simd v128 extension, including new instruction formats and instrDesc definitions. It also enables basic emitter unit testing support for these SIMD instructions, since we are not yet utilizing these instructions in codegen and so we aren't exercising the encoding paths.
Adam Perlinand others
added 6 commits
May 8, 2026 16:10
Adam Perlin
Add Wasm packed SIMD instruction encodings to JIT emitter
53bb222
Add instruction definitions and emitter infrastructure for the WebAssembly
packed SIMD (128-bit) instruction set:
- Add ~200 INST2 entries in instrswasm.h for all SIMD opcodes (0xFD prefix)
- Add 4 new instruction formats: IF_V128_CONST, IF_LANE, IF_MEMARG_LANE,
IF_SHUFFLE in emitfmtswasm.h
- Add instrDesc subclasses in emit.h for SIMD-specific payloads:
instrDescV128Const, instrDescShuffle, instrDescLane, instrDescMemargLane
- Increase TARGET_WASM instruction bit-field to 9 bits (512 max) in emit.h
- Add emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) with size calculation and output encoding in emitwasm.cpp
- Declare new emit functions in emitwasm.h
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Add debug emitter unit tests for Wasm packed SIMD encodings
21f74bc
Add genWasmEmitterUnitTestsSimd() to exercise the new SIMD instruction
emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) and representative plain-opcode SIMD instructions.
Activated via DOTNET_JitEmitUnitTests=* and
DOTNET_JitEmitUnitTestsSections=simd (or all).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Merge branch 'main' of github.com:dotnet/runtime into adamperlin/wasm…
5e5de0f
…-simd-encodings
Adam Perlin
Add temp emitter unit test block to wasm control flow stack and set o…
93d4d06
…rdering number for appropriate branching
Adam Perlin
Use the same instrDesc for v128.const and v128.shuffle
f4c1844
Update emitDispIns to support new SIMD instructions
Properly emit block ... end in emitter unit tests for Wasm
Adam Perlin
Properly emit branch to skip over emitter unit test instructions, and…
917d763
… fix IF_MEMARG_LANE instruction format
CopilotAI
review requested due to automatic review settings
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Pull request overview
This PR wires up emitter-level support for the WebAssembly Packed SIMD (v128 / 0xFD-prefix) instruction set in the experimental Wasm RyuJIT back end. It adds the full SIMD instruction table, new instrDesc shapes and insFormats for the encodings that don't fit existing categories (v128 immediate, lane index, memarg+lane), and a debug-only emitter unit test that exercises the new encoding paths since no real codegen consumes them yet.
Changes:
  • Add the SIMD opcode table (instrswasm.h) and new IF_V128 / IF_LANE / IF_MEMARG_LANE formats with corresponding instrDescV128Imm and instrDescMemargLane descriptor types.
  • Implement emitIns_V128Imm, emitIns_Lane, emitIns_MemargLane, plus matching size/encode/display paths in emitwasm.cpp, and expand _idIns to 9 bits on WASM to fit the larger instruction count.
  • Add genWasmEmitterUnitTestsSimd (DEBUG-only) and hook the Wasm simd test section into genEmitterUnitTests, including a Wasm-specific skip-label scheme using INS_block / INS_br.
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Show a summary per file
FileDescription
src/coreclr/jit/instrswasm.hAdds full v128 SIMD instruction list with IF_OPCODE/IF_MEMARG/IF_V128/IF_LANE/IF_MEMARG_LANE formats and 0xFD prefix.
src/coreclr/jit/emitfmtswasm.hDefines the three new SIMD encoding formats.
src/coreclr/jit/emit.hWidens _idIns to 9 bits on Wasm; adds idIsV128Imm/idIsMemargLaneImm; declares instrDescV128Imm/instrDescMemargLane.
src/coreclr/jit/emitwasm.hDeclares new emit helpers and accessors for the SIMD descriptors.
src/coreclr/jit/emitwasm.cppImplements emit/size/output/display paths for the new formats; also disables IF_CODE_SIZE display with #if FALSE (unrelated to SIMD).
src/coreclr/jit/codegen.hDeclares genWasmEmitterUnitTestsSimd.
src/coreclr/jit/codegenwasm.cppAdds the SIMD emitter unit test with representative coverage across all new formats.
src/coreclr/jit/codegenlinear.cppRoutes the simd unit-test section on Wasm and uses block/br instead of a direct jump to skip over the tests.
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.h
@adamperlin
Potential fix for pull request finding
98f0ffe
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/instrswasm.h
@am11am11
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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara

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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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LGTM, comments and copilot feedback aside
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/codegeninterface.h
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Comment threadsrc/coreclr/jit/instr.cpp
@adamperlin
Potential fix for pull request finding
35b8b7c
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegeninterface.h
Comment threadsrc/coreclr/jit/instr.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.h
Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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@adamperlin
adamperlin
merged commit 18c8c26
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@AndyAyersMSAndyAyersMSAwaiting requested review from AndyAyersMS
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@kgkgkg approved these changes
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Labels

arch-wasmWebAssembly architecturearea-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI

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4 participants

@adamperlin@kg@am11

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
[Wasm RyuJIT] Packed Simd Encodings - #128229
Merged
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
May 22, 2026
Merged
[Wasm RyuJIT] Packed Simd Encodings#128229
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
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@adamperlin
@adamperlinadamperlin
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May 14, 2026

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This PR adds emitter support for the Wasm Packed Simd v128 extension, including new instruction formats and instrDesc definitions. It also enables basic emitter unit testing support for these SIMD instructions, since we are not yet utilizing these instructions in codegen and so we aren't exercising the encoding paths.
Adam Perlinand others
added 6 commits
May 8, 2026 16:10
Adam Perlin
Add Wasm packed SIMD instruction encodings to JIT emitter
53bb222
Add instruction definitions and emitter infrastructure for the WebAssembly
packed SIMD (128-bit) instruction set:
- Add ~200 INST2 entries in instrswasm.h for all SIMD opcodes (0xFD prefix)
- Add 4 new instruction formats: IF_V128_CONST, IF_LANE, IF_MEMARG_LANE,
IF_SHUFFLE in emitfmtswasm.h
- Add instrDesc subclasses in emit.h for SIMD-specific payloads:
instrDescV128Const, instrDescShuffle, instrDescLane, instrDescMemargLane
- Increase TARGET_WASM instruction bit-field to 9 bits (512 max) in emit.h
- Add emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) with size calculation and output encoding in emitwasm.cpp
- Declare new emit functions in emitwasm.h
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Add debug emitter unit tests for Wasm packed SIMD encodings
21f74bc
Add genWasmEmitterUnitTestsSimd() to exercise the new SIMD instruction
emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) and representative plain-opcode SIMD instructions.
Activated via DOTNET_JitEmitUnitTests=* and
DOTNET_JitEmitUnitTestsSections=simd (or all).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Merge branch 'main' of github.com:dotnet/runtime into adamperlin/wasm…
5e5de0f
…-simd-encodings
Adam Perlin
Add temp emitter unit test block to wasm control flow stack and set o…
93d4d06
…rdering number for appropriate branching
Adam Perlin
Use the same instrDesc for v128.const and v128.shuffle
f4c1844
Update emitDispIns to support new SIMD instructions
Properly emit block ... end in emitter unit tests for Wasm
Adam Perlin
Properly emit branch to skip over emitter unit test instructions, and…
917d763
… fix IF_MEMARG_LANE instruction format
CopilotAI
review requested due to automatic review settings
May 14, 2026 21:32
@github-actionsgithub-actionsBot
added
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area-CodeGen-coreclr
CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
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Pull request overview
This PR wires up emitter-level support for the WebAssembly Packed SIMD (v128 / 0xFD-prefix) instruction set in the experimental Wasm RyuJIT back end. It adds the full SIMD instruction table, new instrDesc shapes and insFormats for the encodings that don't fit existing categories (v128 immediate, lane index, memarg+lane), and a debug-only emitter unit test that exercises the new encoding paths since no real codegen consumes them yet.
Changes:
  • Add the SIMD opcode table (instrswasm.h) and new IF_V128 / IF_LANE / IF_MEMARG_LANE formats with corresponding instrDescV128Imm and instrDescMemargLane descriptor types.
  • Implement emitIns_V128Imm, emitIns_Lane, emitIns_MemargLane, plus matching size/encode/display paths in emitwasm.cpp, and expand _idIns to 9 bits on WASM to fit the larger instruction count.
  • Add genWasmEmitterUnitTestsSimd (DEBUG-only) and hook the Wasm simd test section into genEmitterUnitTests, including a Wasm-specific skip-label scheme using INS_block / INS_br.
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Show a summary per file
FileDescription
src/coreclr/jit/instrswasm.hAdds full v128 SIMD instruction list with IF_OPCODE/IF_MEMARG/IF_V128/IF_LANE/IF_MEMARG_LANE formats and 0xFD prefix.
src/coreclr/jit/emitfmtswasm.hDefines the three new SIMD encoding formats.
src/coreclr/jit/emit.hWidens _idIns to 9 bits on Wasm; adds idIsV128Imm/idIsMemargLaneImm; declares instrDescV128Imm/instrDescMemargLane.
src/coreclr/jit/emitwasm.hDeclares new emit helpers and accessors for the SIMD descriptors.
src/coreclr/jit/emitwasm.cppImplements emit/size/output/display paths for the new formats; also disables IF_CODE_SIZE display with #if FALSE (unrelated to SIMD).
src/coreclr/jit/codegen.hDeclares genWasmEmitterUnitTestsSimd.
src/coreclr/jit/codegenwasm.cppAdds the SIMD emitter unit test with representative coverage across all new formats.
src/coreclr/jit/codegenlinear.cppRoutes the simd unit-test section on Wasm and uses block/br instead of a direct jump to skip over the tests.
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.h
@adamperlin
Potential fix for pull request finding
98f0ffe
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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review requested due to automatic review settings
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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/instrswasm.h
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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara

See info in area-owners.md if you want to be subscribed.

This was referenced May 15, 2026

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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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LGTM, comments and copilot feedback aside
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/codegeninterface.h
Outdated

Comment threadsrc/coreclr/jit/instr.cpp
@adamperlin
Potential fix for pull request finding
35b8b7c
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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review requested due to automatic review settings
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegeninterface.h
Comment threadsrc/coreclr/jit/instr.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.h
Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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review requested due to automatic review settings
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

@adamperlin
adamperlin
merged commit 18c8c26
into
dotnet:mainMay 22, 2026

137 of 139 checks passed

@adamperlin
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deleted the

adamperlin/wasm-simd-encodings

branch
May 22, 2026 21:06
@dotnet-maestrodotnet-maestroBot
mentioned this pull request
May 23, 2026
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added this to the 11.0-preview6 milestone
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
[Wasm RyuJIT] Packed Simd Encodings - #128229
Merged
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
May 22, 2026
Merged
[Wasm RyuJIT] Packed Simd Encodings#128229
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
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This PR adds emitter support for the Wasm Packed Simd v128 extension, including new instruction formats and instrDesc definitions. It also enables basic emitter unit testing support for these SIMD instructions, since we are not yet utilizing these instructions in codegen and so we aren't exercising the encoding paths.
Adam Perlinand others
added 6 commits
May 8, 2026 16:10
Adam Perlin
Add Wasm packed SIMD instruction encodings to JIT emitter
53bb222
Add instruction definitions and emitter infrastructure for the WebAssembly
packed SIMD (128-bit) instruction set:
- Add ~200 INST2 entries in instrswasm.h for all SIMD opcodes (0xFD prefix)
- Add 4 new instruction formats: IF_V128_CONST, IF_LANE, IF_MEMARG_LANE,
IF_SHUFFLE in emitfmtswasm.h
- Add instrDesc subclasses in emit.h for SIMD-specific payloads:
instrDescV128Const, instrDescShuffle, instrDescLane, instrDescMemargLane
- Increase TARGET_WASM instruction bit-field to 9 bits (512 max) in emit.h
- Add emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) with size calculation and output encoding in emitwasm.cpp
- Declare new emit functions in emitwasm.h
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Add debug emitter unit tests for Wasm packed SIMD encodings
21f74bc
Add genWasmEmitterUnitTestsSimd() to exercise the new SIMD instruction
emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) and representative plain-opcode SIMD instructions.
Activated via DOTNET_JitEmitUnitTests=* and
DOTNET_JitEmitUnitTestsSections=simd (or all).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Merge branch 'main' of github.com:dotnet/runtime into adamperlin/wasm…
5e5de0f
…-simd-encodings
Adam Perlin
Add temp emitter unit test block to wasm control flow stack and set o…
93d4d06
…rdering number for appropriate branching
Adam Perlin
Use the same instrDesc for v128.const and v128.shuffle
f4c1844
Update emitDispIns to support new SIMD instructions
Properly emit block ... end in emitter unit tests for Wasm
Adam Perlin
Properly emit branch to skip over emitter unit test instructions, and…
917d763
… fix IF_MEMARG_LANE instruction format
CopilotAI
review requested due to automatic review settings
May 14, 2026 21:32
@github-actionsgithub-actionsBot
added
the 
area-CodeGen-coreclr
CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
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Pull request overview
This PR wires up emitter-level support for the WebAssembly Packed SIMD (v128 / 0xFD-prefix) instruction set in the experimental Wasm RyuJIT back end. It adds the full SIMD instruction table, new instrDesc shapes and insFormats for the encodings that don't fit existing categories (v128 immediate, lane index, memarg+lane), and a debug-only emitter unit test that exercises the new encoding paths since no real codegen consumes them yet.
Changes:
  • Add the SIMD opcode table (instrswasm.h) and new IF_V128 / IF_LANE / IF_MEMARG_LANE formats with corresponding instrDescV128Imm and instrDescMemargLane descriptor types.
  • Implement emitIns_V128Imm, emitIns_Lane, emitIns_MemargLane, plus matching size/encode/display paths in emitwasm.cpp, and expand _idIns to 9 bits on WASM to fit the larger instruction count.
  • Add genWasmEmitterUnitTestsSimd (DEBUG-only) and hook the Wasm simd test section into genEmitterUnitTests, including a Wasm-specific skip-label scheme using INS_block / INS_br.
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Show a summary per file
FileDescription
src/coreclr/jit/instrswasm.hAdds full v128 SIMD instruction list with IF_OPCODE/IF_MEMARG/IF_V128/IF_LANE/IF_MEMARG_LANE formats and 0xFD prefix.
src/coreclr/jit/emitfmtswasm.hDefines the three new SIMD encoding formats.
src/coreclr/jit/emit.hWidens _idIns to 9 bits on Wasm; adds idIsV128Imm/idIsMemargLaneImm; declares instrDescV128Imm/instrDescMemargLane.
src/coreclr/jit/emitwasm.hDeclares new emit helpers and accessors for the SIMD descriptors.
src/coreclr/jit/emitwasm.cppImplements emit/size/output/display paths for the new formats; also disables IF_CODE_SIZE display with #if FALSE (unrelated to SIMD).
src/coreclr/jit/codegen.hDeclares genWasmEmitterUnitTestsSimd.
src/coreclr/jit/codegenwasm.cppAdds the SIMD emitter unit test with representative coverage across all new formats.
src/coreclr/jit/codegenlinear.cppRoutes the simd unit-test section on Wasm and uses block/br instead of a direct jump to skip over the tests.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/codegenwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.h
@adamperlin
Potential fix for pull request finding
98f0ffe
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/codegenwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/codegenlinear.cpp
Outdated

Comment threadsrc/coreclr/jit/instrswasm.h
@am11am11
added
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arch-wasm
WebAssembly architecture
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May 14, 2026
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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara

See info in area-owners.md if you want to be subscribed.

This was referenced May 15, 2026

Open


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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Outdated

Comment threadsrc/coreclr/jit/codegenlinear.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
kg
kg
reviewed
May 21, 2026
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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LGTM, comments and copilot feedback aside
@build-analysisbuild-analysisBot
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/codegeninterface.h
Outdated

Comment threadsrc/coreclr/jit/instr.cpp
@adamperlin
Potential fix for pull request finding
35b8b7c
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
May 21, 2026 22:07
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegeninterface.h
Comment threadsrc/coreclr/jit/instr.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.h
Comment threadsrc/coreclr/jit/codegenwasm.cpp
CopilotAI
review requested due to automatic review settings
May 21, 2026 22:29
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
CopilotAI
review requested due to automatic review settings
May 22, 2026 00:29
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

@adamperlin
adamperlin
merged commit 18c8c26
into
dotnet:mainMay 22, 2026

137 of 139 checks passed

@adamperlin
adamperlin
deleted the

adamperlin/wasm-simd-encodings

branch
May 22, 2026 21:06
@dotnet-maestrodotnet-maestroBot
mentioned this pull request
May 23, 2026
 Merged

@dotnet-milestone-botdotnet-milestone-botBot
added this to the 11.0-preview6 milestone
May 23, 2026
@adamperlinadamperlin
mentioned this pull request
May 29, 2026

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Copilot code reviewCopilot
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Copilot left review comments
@AndyAyersMSAndyAyersMSAwaiting requested review from AndyAyersMS
@tannergoodingtannergoodingAwaiting requested review from tannergooding

+1 more reviewer

@kgkgkg approved these changes
Reviewers whose approvals may not affect merge requirements

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Labels

arch-wasmWebAssembly architecturearea-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI

Projects


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Milestone

11.0-preview6

Development

Successfully merging this pull request may close these issues.

4 participants

@adamperlin@kg@am11

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
[Wasm RyuJIT] Packed Simd Encodings - #128229
Merged
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
May 22, 2026
Merged
[Wasm RyuJIT] Packed Simd Encodings#128229
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
Conversation
@adamperlin
@adamperlinadamperlin
commented
May 14, 2026

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This PR adds emitter support for the Wasm Packed Simd v128 extension, including new instruction formats and instrDesc definitions. It also enables basic emitter unit testing support for these SIMD instructions, since we are not yet utilizing these instructions in codegen and so we aren't exercising the encoding paths.
Adam Perlinand others
added 6 commits
May 8, 2026 16:10
Adam Perlin
Add Wasm packed SIMD instruction encodings to JIT emitter
53bb222
Add instruction definitions and emitter infrastructure for the WebAssembly
packed SIMD (128-bit) instruction set:
- Add ~200 INST2 entries in instrswasm.h for all SIMD opcodes (0xFD prefix)
- Add 4 new instruction formats: IF_V128_CONST, IF_LANE, IF_MEMARG_LANE,
IF_SHUFFLE in emitfmtswasm.h
- Add instrDesc subclasses in emit.h for SIMD-specific payloads:
instrDescV128Const, instrDescShuffle, instrDescLane, instrDescMemargLane
- Increase TARGET_WASM instruction bit-field to 9 bits (512 max) in emit.h
- Add emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) with size calculation and output encoding in emitwasm.cpp
- Declare new emit functions in emitwasm.h
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Add debug emitter unit tests for Wasm packed SIMD encodings
21f74bc
Add genWasmEmitterUnitTestsSimd() to exercise the new SIMD instruction
emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) and representative plain-opcode SIMD instructions.
Activated via DOTNET_JitEmitUnitTests=* and
DOTNET_JitEmitUnitTestsSections=simd (or all).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Merge branch 'main' of github.com:dotnet/runtime into adamperlin/wasm…
5e5de0f
…-simd-encodings
Adam Perlin
Add temp emitter unit test block to wasm control flow stack and set o…
93d4d06
…rdering number for appropriate branching
Adam Perlin
Use the same instrDesc for v128.const and v128.shuffle
f4c1844
Update emitDispIns to support new SIMD instructions
Properly emit block ... end in emitter unit tests for Wasm
Adam Perlin
Properly emit branch to skip over emitter unit test instructions, and…
917d763
… fix IF_MEMARG_LANE instruction format
CopilotAI
review requested due to automatic review settings
May 14, 2026 21:32
@github-actionsgithub-actionsBot
added
the 
area-CodeGen-coreclr
CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
label
May 14, 2026
CopilotAI
reviewed
May 14, 2026
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Pull request overview
This PR wires up emitter-level support for the WebAssembly Packed SIMD (v128 / 0xFD-prefix) instruction set in the experimental Wasm RyuJIT back end. It adds the full SIMD instruction table, new instrDesc shapes and insFormats for the encodings that don't fit existing categories (v128 immediate, lane index, memarg+lane), and a debug-only emitter unit test that exercises the new encoding paths since no real codegen consumes them yet.
Changes:
  • Add the SIMD opcode table (instrswasm.h) and new IF_V128 / IF_LANE / IF_MEMARG_LANE formats with corresponding instrDescV128Imm and instrDescMemargLane descriptor types.
  • Implement emitIns_V128Imm, emitIns_Lane, emitIns_MemargLane, plus matching size/encode/display paths in emitwasm.cpp, and expand _idIns to 9 bits on WASM to fit the larger instruction count.
  • Add genWasmEmitterUnitTestsSimd (DEBUG-only) and hook the Wasm simd test section into genEmitterUnitTests, including a Wasm-specific skip-label scheme using INS_block / INS_br.
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Show a summary per file
FileDescription
src/coreclr/jit/instrswasm.hAdds full v128 SIMD instruction list with IF_OPCODE/IF_MEMARG/IF_V128/IF_LANE/IF_MEMARG_LANE formats and 0xFD prefix.
src/coreclr/jit/emitfmtswasm.hDefines the three new SIMD encoding formats.
src/coreclr/jit/emit.hWidens _idIns to 9 bits on Wasm; adds idIsV128Imm/idIsMemargLaneImm; declares instrDescV128Imm/instrDescMemargLane.
src/coreclr/jit/emitwasm.hDeclares new emit helpers and accessors for the SIMD descriptors.
src/coreclr/jit/emitwasm.cppImplements emit/size/output/display paths for the new formats; also disables IF_CODE_SIZE display with #if FALSE (unrelated to SIMD).
src/coreclr/jit/codegen.hDeclares genWasmEmitterUnitTestsSimd.
src/coreclr/jit/codegenwasm.cppAdds the SIMD emitter unit test with representative coverage across all new formats.
src/coreclr/jit/codegenlinear.cppRoutes the simd unit-test section on Wasm and uses block/br instead of a direct jump to skip over the tests.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/codegenwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.h
@adamperlin
Potential fix for pull request finding
98f0ffe
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 21:43
CopilotAI
reviewed
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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/codegenwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/codegenlinear.cpp
Outdated

Comment threadsrc/coreclr/jit/instrswasm.h
@am11am11
added
the 
arch-wasm
WebAssembly architecture
label
May 14, 2026
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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara

See info in area-owners.md if you want to be subscribed.

This was referenced May 15, 2026

Open


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Open

CopilotAI
review requested due to automatic review settings
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reviewed
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Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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LGTM, comments and copilot feedback aside
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/codegeninterface.h
Outdated

Comment threadsrc/coreclr/jit/instr.cpp
@adamperlin
Potential fix for pull request finding
35b8b7c
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegeninterface.h
Comment threadsrc/coreclr/jit/instr.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.h
Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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review requested due to automatic review settings
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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@adamperlin
adamperlin
merged commit 18c8c26
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@AndyAyersMSAndyAyersMSAwaiting requested review from AndyAyersMS
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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[Wasm RyuJIT] Packed Simd Encodings - #128229
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adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
May 22, 2026
Merged
[Wasm RyuJIT] Packed Simd Encodings#128229
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
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This PR adds emitter support for the Wasm Packed Simd v128 extension, including new instruction formats and instrDesc definitions. It also enables basic emitter unit testing support for these SIMD instructions, since we are not yet utilizing these instructions in codegen and so we aren't exercising the encoding paths.
Adam Perlinand others
added 6 commits
May 8, 2026 16:10
Adam Perlin
Add Wasm packed SIMD instruction encodings to JIT emitter
53bb222
Add instruction definitions and emitter infrastructure for the WebAssembly
packed SIMD (128-bit) instruction set:
- Add ~200 INST2 entries in instrswasm.h for all SIMD opcodes (0xFD prefix)
- Add 4 new instruction formats: IF_V128_CONST, IF_LANE, IF_MEMARG_LANE,
IF_SHUFFLE in emitfmtswasm.h
- Add instrDesc subclasses in emit.h for SIMD-specific payloads:
instrDescV128Const, instrDescShuffle, instrDescLane, instrDescMemargLane
- Increase TARGET_WASM instruction bit-field to 9 bits (512 max) in emit.h
- Add emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) with size calculation and output encoding in emitwasm.cpp
- Declare new emit functions in emitwasm.h
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Add debug emitter unit tests for Wasm packed SIMD encodings
21f74bc
Add genWasmEmitterUnitTestsSimd() to exercise the new SIMD instruction
emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) and representative plain-opcode SIMD instructions.
Activated via DOTNET_JitEmitUnitTests=* and
DOTNET_JitEmitUnitTestsSections=simd (or all).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Merge branch 'main' of github.com:dotnet/runtime into adamperlin/wasm…
5e5de0f
…-simd-encodings
Adam Perlin
Add temp emitter unit test block to wasm control flow stack and set o…
93d4d06
…rdering number for appropriate branching
Adam Perlin
Use the same instrDesc for v128.const and v128.shuffle
f4c1844
Update emitDispIns to support new SIMD instructions
Properly emit block ... end in emitter unit tests for Wasm
Adam Perlin
Properly emit branch to skip over emitter unit test instructions, and…
917d763
… fix IF_MEMARG_LANE instruction format
CopilotAI
review requested due to automatic review settings
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added
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area-CodeGen-coreclr
CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
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Pull request overview
This PR wires up emitter-level support for the WebAssembly Packed SIMD (v128 / 0xFD-prefix) instruction set in the experimental Wasm RyuJIT back end. It adds the full SIMD instruction table, new instrDesc shapes and insFormats for the encodings that don't fit existing categories (v128 immediate, lane index, memarg+lane), and a debug-only emitter unit test that exercises the new encoding paths since no real codegen consumes them yet.
Changes:
  • Add the SIMD opcode table (instrswasm.h) and new IF_V128 / IF_LANE / IF_MEMARG_LANE formats with corresponding instrDescV128Imm and instrDescMemargLane descriptor types.
  • Implement emitIns_V128Imm, emitIns_Lane, emitIns_MemargLane, plus matching size/encode/display paths in emitwasm.cpp, and expand _idIns to 9 bits on WASM to fit the larger instruction count.
  • Add genWasmEmitterUnitTestsSimd (DEBUG-only) and hook the Wasm simd test section into genEmitterUnitTests, including a Wasm-specific skip-label scheme using INS_block / INS_br.
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Show a summary per file
FileDescription
src/coreclr/jit/instrswasm.hAdds full v128 SIMD instruction list with IF_OPCODE/IF_MEMARG/IF_V128/IF_LANE/IF_MEMARG_LANE formats and 0xFD prefix.
src/coreclr/jit/emitfmtswasm.hDefines the three new SIMD encoding formats.
src/coreclr/jit/emit.hWidens _idIns to 9 bits on Wasm; adds idIsV128Imm/idIsMemargLaneImm; declares instrDescV128Imm/instrDescMemargLane.
src/coreclr/jit/emitwasm.hDeclares new emit helpers and accessors for the SIMD descriptors.
src/coreclr/jit/emitwasm.cppImplements emit/size/output/display paths for the new formats; also disables IF_CODE_SIZE display with #if FALSE (unrelated to SIMD).
src/coreclr/jit/codegen.hDeclares genWasmEmitterUnitTestsSimd.
src/coreclr/jit/codegenwasm.cppAdds the SIMD emitter unit test with representative coverage across all new formats.
src/coreclr/jit/codegenlinear.cppRoutes the simd unit-test section on Wasm and uses block/br instead of a direct jump to skip over the tests.
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.h
@adamperlin
Potential fix for pull request finding
98f0ffe
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/instrswasm.h
@am11am11
added
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May 14, 2026
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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara

See info in area-owners.md if you want to be subscribed.

This was referenced May 15, 2026

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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Outdated

Comment threadsrc/coreclr/jit/codegenlinear.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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May 21, 2026
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LGTM, comments and copilot feedback aside
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/codegeninterface.h
Outdated

Comment threadsrc/coreclr/jit/instr.cpp
@adamperlin
Potential fix for pull request finding
35b8b7c
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegeninterface.h
Comment threadsrc/coreclr/jit/instr.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

Comment threadsrc/coreclr/jit/emitwasm.h
Comment threadsrc/coreclr/jit/codegenwasm.cpp
CopilotAI
review requested due to automatic review settings
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
CopilotAI
review requested due to automatic review settings
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Outdated

@adamperlin
adamperlin
merged commit 18c8c26
into
dotnet:mainMay 22, 2026

137 of 139 checks passed

@adamperlin
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deleted the

adamperlin/wasm-simd-encodings

branch
May 22, 2026 21:06
@dotnet-maestrodotnet-maestroBot
mentioned this pull request
May 23, 2026
 Merged

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added this to the 11.0-preview6 milestone
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@AndyAyersMSAndyAyersMSAwaiting requested review from AndyAyersMS
@tannergoodingtannergoodingAwaiting requested review from tannergooding

+1 more reviewer

@kgkgkg approved these changes
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11.0-preview6

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@adamperlin@kg@am11

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

Skip to content
[Wasm RyuJIT] Packed Simd Encodings - #128229
Merged
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
May 22, 2026
Merged
[Wasm RyuJIT] Packed Simd Encodings#128229
adamperlin merged 25 commits into
dotnet:mainfrom 
adamperlin:adamperlin/wasm-simd-encodings
Conversation
@adamperlin
@adamperlinadamperlin
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This PR adds emitter support for the Wasm Packed Simd v128 extension, including new instruction formats and instrDesc definitions. It also enables basic emitter unit testing support for these SIMD instructions, since we are not yet utilizing these instructions in codegen and so we aren't exercising the encoding paths.
Adam Perlinand others
added 6 commits
May 8, 2026 16:10
Adam Perlin
Add Wasm packed SIMD instruction encodings to JIT emitter
53bb222
Add instruction definitions and emitter infrastructure for the WebAssembly
packed SIMD (128-bit) instruction set:
- Add ~200 INST2 entries in instrswasm.h for all SIMD opcodes (0xFD prefix)
- Add 4 new instruction formats: IF_V128_CONST, IF_LANE, IF_MEMARG_LANE,
IF_SHUFFLE in emitfmtswasm.h
- Add instrDesc subclasses in emit.h for SIMD-specific payloads:
instrDescV128Const, instrDescShuffle, instrDescLane, instrDescMemargLane
- Increase TARGET_WASM instruction bit-field to 9 bits (512 max) in emit.h
- Add emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) with size calculation and output encoding in emitwasm.cpp
- Declare new emit functions in emitwasm.h
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Add debug emitter unit tests for Wasm packed SIMD encodings
21f74bc
Add genWasmEmitterUnitTestsSimd() to exercise the new SIMD instruction
emit functions (emitIns_V128Const, emitIns_Lane, emitIns_MemargLane,
emitIns_Shuffle) and representative plain-opcode SIMD instructions.
Activated via DOTNET_JitEmitUnitTests=* and
DOTNET_JitEmitUnitTestsSections=simd (or all).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adam Perlin
Merge branch 'main' of github.com:dotnet/runtime into adamperlin/wasm…
5e5de0f
…-simd-encodings
Adam Perlin
Add temp emitter unit test block to wasm control flow stack and set o…
93d4d06
…rdering number for appropriate branching
Adam Perlin
Use the same instrDesc for v128.const and v128.shuffle
f4c1844
Update emitDispIns to support new SIMD instructions
Properly emit block ... end in emitter unit tests for Wasm
Adam Perlin
Properly emit branch to skip over emitter unit test instructions, and…
917d763
… fix IF_MEMARG_LANE instruction format
CopilotAI
review requested due to automatic review settings
May 14, 2026 21:32
@github-actionsgithub-actionsBot
added
the 
area-CodeGen-coreclr
CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
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Pull request overview
This PR wires up emitter-level support for the WebAssembly Packed SIMD (v128 / 0xFD-prefix) instruction set in the experimental Wasm RyuJIT back end. It adds the full SIMD instruction table, new instrDesc shapes and insFormats for the encodings that don't fit existing categories (v128 immediate, lane index, memarg+lane), and a debug-only emitter unit test that exercises the new encoding paths since no real codegen consumes them yet.
Changes:
  • Add the SIMD opcode table (instrswasm.h) and new IF_V128 / IF_LANE / IF_MEMARG_LANE formats with corresponding instrDescV128Imm and instrDescMemargLane descriptor types.
  • Implement emitIns_V128Imm, emitIns_Lane, emitIns_MemargLane, plus matching size/encode/display paths in emitwasm.cpp, and expand _idIns to 9 bits on WASM to fit the larger instruction count.
  • Add genWasmEmitterUnitTestsSimd (DEBUG-only) and hook the Wasm simd test section into genEmitterUnitTests, including a Wasm-specific skip-label scheme using INS_block / INS_br.
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
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src/coreclr/jit/instrswasm.hAdds full v128 SIMD instruction list with IF_OPCODE/IF_MEMARG/IF_V128/IF_LANE/IF_MEMARG_LANE formats and 0xFD prefix.
src/coreclr/jit/emitfmtswasm.hDefines the three new SIMD encoding formats.
src/coreclr/jit/emit.hWidens _idIns to 9 bits on Wasm; adds idIsV128Imm/idIsMemargLaneImm; declares instrDescV128Imm/instrDescMemargLane.
src/coreclr/jit/emitwasm.hDeclares new emit helpers and accessors for the SIMD descriptors.
src/coreclr/jit/emitwasm.cppImplements emit/size/output/display paths for the new formats; also disables IF_CODE_SIZE display with #if FALSE (unrelated to SIMD).
src/coreclr/jit/codegen.hDeclares genWasmEmitterUnitTestsSimd.
src/coreclr/jit/codegenwasm.cppAdds the SIMD emitter unit test with representative coverage across all new formats.
src/coreclr/jit/codegenlinear.cppRoutes the simd unit-test section on Wasm and uses block/br instead of a direct jump to skip over the tests.
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/codegenwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.h
@adamperlin
Potential fix for pull request finding
98f0ffe
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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 8 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/instrswasm.h
@am11am11
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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara

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This was referenced May 15, 2026

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Pull request overview
Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/codegenlinear.cpp
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Comment threadsrc/coreclr/jit/emitwasm.cpp
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LGTM, comments and copilot feedback aside
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/codegeninterface.h
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Comment threadsrc/coreclr/jit/instr.cpp
@adamperlin
Potential fix for pull request finding
35b8b7c
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 5 comments.
Comment threadsrc/coreclr/jit/codegeninterface.h
Comment threadsrc/coreclr/jit/instr.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Comment threadsrc/coreclr/jit/emitwasm.h
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.
Comment threadsrc/coreclr/jit/codegenlinear.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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Pull request overview
Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.
Comment threadsrc/coreclr/jit/emitwasm.cpp
Comment threadsrc/coreclr/jit/emitwasm.cpp
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@adamperlin
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@AndyAyersMSAndyAyersMSAwaiting requested review from AndyAyersMS
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arch-wasmWebAssembly architecturearea-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI

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