Wasm R2R Pri0 Codegen Issues

[AndyAyersMS]

Summary

Tracking issue for Wasm R2R codegen failures found while running browser-wasm Pri0 tests with Crossgen2 enabled, after all the recent EH changes have landed.

Failure classes

• LSRA: GT_FRAME_SIZE treated as a binary node

  • Assert: m_node->OperIsBinary()
  • Phase: Linear scan register alloc
  • This is just a simple oversight, fix is trivial.

• Wasm control flow: missing EH index

  • Assert: block->hasHndIndex() == true
  • Phase: Wasm control flow
  • This is an orphaned dont-remove throw block in a try; it ends up being placed in the wrong spot in the linearized flow. Fix is to try harder to remove these hard to remove things, or find a way to tolerate them.

• Wasm transform SCCs: bitset bounds assert

  • Assert: i < BitSetTraits::GetSize(env)
  • Phase: Wasm transform sccs
  • This is an unreachable try, these are also hard to remove and cause similar problems to the unreachable blocks in a try.

• Lowering nodeinfo: local address containment assert

  • Assert: lclVarAddr->isContained() || !varDsc->lvTracked || varTypeIsStruct(varDsc)
  • Phase: Lowering nodeinfo
  • Not sure what this is yet. Perhaps we can suppress the assert, which seems to be concerned with emitter GC liveness tracking. Perhaps not.

Repro instructions below.

Note

This issue was created with assistance from GitHub Copilot.

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[AndyAyersMS]

Initial setup

Starting from a clean checkout of dotnet/runtime main on Windows:

build.cmd clr+libs -rc debug -c release -os browser
src\tests\build.cmd browser

Then run the JIT subtree with browser-wasm R2R enabled:

src\tests\run.cmd wasm runcrossgen2tests tree JIT logsdir <log-dir>

The repros below assume the browser-wasm Debug test layout exists under:

artifacts\tests\coreclr\browser.wasm.Debug

Note

This comment was created with assistance from GitHub Copilot.

[AndyAyersMS]

Repro: LSRA GT_FRAME_SIZE use-edge assert

After building browser-wasm tests, run:

set CORE_ROOT=%REPO%\artifacts\tests\coreclr\browser.wasm.Debug\Tests\Core_Root
set TEST_DIR=%REPO%\artifacts\tests\coreclr\browser.wasm.Debug\JIT\Directed\Directed_3

%CORE_ROOT%\crossgen2\crossgen2.exe ^
  @%TEST_DIR%\ExplicitTailCallNoSO.single.wasm.rsp ^
  -r:%TEST_DIR%\IL-CG2\*.dll ^
  --singlemethodtypename "ExplicitTailCallNoSO,ExplicitTailCallNoSO" ^
  --singlemethodname "CalculateSumWithTailCall" ^
  --singlemethodindex 1

Expected assert:

Assertion failed 'm_node->OperIsBinary()' ... during 'Linear scan register alloc'

Note

This comment was created with assistance from GitHub Copilot.

[AndyAyersMS]

Repro: Wasm control flow EH-index assert

set CORE_ROOT=%REPO%\artifacts\tests\coreclr\browser.wasm.Debug\Tests\Core_Root
set TEST_DIR=%REPO%\artifacts\tests\coreclr\browser.wasm.Debug\JIT\Regression\Regression_PdbOnly_r_1

%CORE_ROOT%\crossgen2\crossgen2.exe ^
  @%TEST_DIR%\Regression_PdbOnly_r_1.wasm.rsp ^
  @<rsp-containing-explicit-refs-to-each-%TEST_DIR%\IL-CG2\*.dll> ^
  --singlemethodtypename "b27824.AA,Regression_PdbOnly_r_1" ^
  --singlemethodname "TestEntryPoint" ^
  --singlemethodindex 1

Expected assert:

Assertion failed 'block->hasHndIndex() == true' ... during 'Wasm control flow'

Note

This comment was created with assistance from GitHub Copilot.

[AndyAyersMS]

Repro: Wasm transform SCCs bitset assert

set CORE_ROOT=%REPO%\artifacts\tests\coreclr\browser.wasm.Debug\Tests\Core_Root
set TEST_DIR=%REPO%\artifacts\tests\coreclr\browser.wasm.Debug\JIT\Regression\Regression_PdbOnly_r_2

%CORE_ROOT%\crossgen2\crossgen2.exe ^
  @%TEST_DIR%\Regression_PdbOnly_r_2.wasm.rsp ^
  @<rsp-containing-explicit-refs-to-each-%TEST_DIR%\IL-CG2\*.dll> ^
  --singlemethodtypename "b63183.AA,Regression_PdbOnly_r_2" ^
  --singlemethodname "TestEntryPoint" ^
  --singlemethodindex 1

Expected assert:

Assertion failed 'i < BitSetTraits::GetSize(env)' ... during 'Wasm transform sccs'

Note

This comment was created with assistance from GitHub Copilot.

[AndyAyersMS]

Repro: Lowering nodeinfo local-address containment assert

set CORE_ROOT=%REPO%\artifacts\tests\coreclr\browser.wasm.Debug\Tests\Core_Root
set TEST_DIR=%REPO%\artifacts\tests\coreclr\browser.wasm.Debug\JIT\Regression\Regression_ro_1

%CORE_ROOT%\crossgen2\crossgen2.exe ^
  @%TEST_DIR%\Regression_ro_1.wasm.rsp ^
  @<rsp-containing-explicit-refs-to-each-%TEST_DIR%\IL-CG2\*.dll> ^
  --singlemethodtypename "Runtime_45557.ObjectBinder,Regression_ro_1" ^
  --singlemethodname "GetSnapshot" ^
  --singlemethodindex 1

Expected assert:

Assertion failed 'lclVarAddr->isContained() || !varDsc->lvTracked || varTypeIsStruct(varDsc)' ... during 'Lowering nodeinfo'

Note

This comment was created with assistance from GitHub Copilot.