JIT: properly update trees in optOptimizeBoolsGcStress

[AndyAyersMS]

Under jit stress, optOptimizeBoolsGcStress will modify trees. Since this now happens in a phase that runs after fgSetBlockOrder, it must also recost and rethread the trees.

Fixes#75944.

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Issue Details

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Under jit stress, optOptimizeBoolsGcStress will modify trees. Since this now happens in a phase that runs after fgSetBlockOrder, it must also recost and rethread the trees.

Fixes #75944.

Author:	AndyAyersMS
Assignees:	-
Labels:	area-CodeGen-coreclr
Milestone:	-

[AndyAyersMS]

@jakobbotsch PTAL
cc @dotnet/jit-contrib

Likely also fixes #75942 and #75941.

[AndyAyersMS]

/azp run runtime-coreclr jitstress

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[AndyAyersMS]

Still seeing some failures so will need to revise this.

[AndyAyersMS]

We are ending up with out of order threading, despite calling fgSetStmtSeq. Seems like we are recosting part of the tree after this call, which leads to operand swapping after threading. Since OOB runs later now than it once did, there is no need to recost.

[AndyAyersMS]

Not the first time I've been surprised by gtPrepareCost's operand swapping, and probably not the last.

[AndyAyersMS]

/azp run runtime-coreclr jitstress

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[AndyAyersMS]

Another segfault from msbuild during restore:

/__w/1/s/.dotnet/sdk/7.0.100-preview.7.22377.5/MSBuild.dll /nologo -maxcpucount /m -verbosity:m /v:minimal /bl:/__w/1/s/artifacts/log/Checked/ToolsetRestore.binlog /clp:Summary /clp:ErrorsOnly;NoSummary /nr:false /p:TreatWarningsAsErrors=true /p:ContinuousIntegrationBuild=true /p:__ToolsetLocationOutputFile=/__w/1/s/artifacts/toolset/8.0.0-beta.22469.1.txt /t:__WriteToolsetLocation /warnaserror /__w/1/s/artifacts/toolset/restore.proj
/__w/1/s/eng/common/tools.sh: line 474: 503 Segmentation fault (core dumped) "$_InitializeBuildTool" "$@"

[AndyAyersMS]

Arm64 SPMI is lack of MCH, perhaps I'm too close to a GUID update or collections are broken?

No Azure Storage MCH files to download from 11b4ea58-c400-4c3d-995e-4e2f0676f6e8/linux/arm64/

[AndyAyersMS]

x86 failure is in CriticalFinalizer which is supposedly fixed by #75952.

[AndyAyersMS]

More critical finalizer failures in the jitstress legs. So far, no other failures there.