[wasm][R2R] crossgen2 aborts compiling HardwareIntrinsics General Vector128_1 tests for browser-wasm #134976

Description

In the browser-wasm R2R_CG2 runtime-test lane, crossgen2 aborts (exit code 134, core dumped) while compiling Vector128_1_r.dll and Vector128_1_ro.dll from JIT/HardwareIntrinsics/General/Vector128_1. Nothing is written to stdout or stderr before the abort:

Running CrossGen2:  .../crossgen2/crossgen2 @.../HardwareIntrinsics_General_r/Vector128_1_r.wasm.rsp   -r:.../HardwareIntrinsics_General_r/IL-CG2/*.dll -f wasm
[createdump] The app model does not support crash report generation
[createdump] Failure took 0ms
[createdump] Target process is alive
JIT/HardwareIntrinsics/HardwareIntrinsics_General_r/HardwareIntrinsics_General_r.sh: line 258:   300 Aborted                    (core dumped) $__Command
Crossgen2 failed with exitcode: 134

crossgen2 options:
-O --targetarch:wasm --targetos:browser --verify-type-and-field-layout --method-layout:random --codegenopt:JitWasmNyiToR2RUnsupported=1 --verify-gc-mode-transitions

The merged runner stops at the first crossgen2 failure, so no test in HardwareIntrinsics_General_r or HardwareIntrinsics_General_ro runs under R2R. The assemblies compiled before this one (NotSupported_r, ScalarConstantFoldings, SimdConstantFoldings, TestLibrary) succeeded. It is not yet known whether the remaining Vector* assemblies compile.

Both runners pass in the browser-wasm interpreter leg.

A core dump (core.1000.300) is uploaded to the HardwareIntrinsics_General_r work item.

Local investigation

Reproduced locally with a browser-wasm Checked build (osx-arm64 host crossgen2). With Vector128_1_* excluded, crossgen2 next fails on Vector128_r.dll. On macOS it does not abort; several JIT worker threads spin at the same place:

Lowering::DoPhase()                                   lower.cpp:8960
Lowering::LowerBlock(BasicBlock*)                     lower.cpp:9297
Lowering::LowerStoreLocCommon(GenTreeLclVarCommon*)
Lowering::LowerStoreLocCommon (.cold.1)               lower.cpp:5661
PAL_DispatchExceptionWrapper -> PAL_DispatchException -> PAL_DispatchExceptionInner -> RestoreCompleteContext

lower.cpp:5661 is the return LowerStoreLocCommon(lclStore); after SpillStructCallResult, on the path for a struct call result that has a single return register and can't be retyped to a primitive. The fault there is re-dispatched over and over. On Linux Helix the same fault shows up as the exit-134 abort above.

Because more than one assembly in the runner is affected, the quarantine turns off ReadyToRun for the HardwareIntrinsics_General_r/_ro runners on wasm CoreCLR. Their interpreter coverage is kept.

Configuration

• browser-wasm, CoreCLR, Checked, R2R_CG2 (crossgen2 at Helix time), Linux x64 host
• Seen in runtime-coreclr outerloop on [wasm][CoreCLR] Add browser_wasm R2R_CG2 leg to runtime-coreclr outerloop #134960: build 1618213, Helix job 470668a9-1c32-41f9-ac2c-a8a0ddd812c3, work items HardwareIntrinsics_General_r and HardwareIntrinsics_General_ro