Fix AltJit and VectorT ISA specification #113901
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When running as an AltJit when the generated code will not be used (either because of a mismatched VM, or because RunAltJitCode=0), the JIT overwrites the passed in ISAs. When it does so, it zeros out the VectorT* ISA flags. Instead of this, carry over the existing ISA flags. This should work for same-architecture SPMI replays. I'm not sure if additional logic for specifically setting the VectorT* ISA is required for other scenarios, or if incorporating similar logic to `EEJitManager::SetCpuInfo()` into `Compiler::compCompile()` is required. Adds new JIT debugging helpers `dIsa()` and `dIsaFlags()` to dump out string representations of `CORINFO_InstructionSet` and `CORINFO_InstructionSetFlags`. Fixes dotnet#113869
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/azp run runtime-coreclr superpmi-replay-apx |
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/azp run runtime-coreclr superpmi-replay-apx |
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@kunalspathak @dotnet/jit-contrib PTAL |
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/azp run runtime-coreclr superpmi-replay-apx |
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This looks reasonable to me, provided it solves the apx related failures highlighted in the original issue, but still might not handle cases that I mentioned in #113869 (comment)
True. I think you need to find the JIT-EE call(s) that lead to failures and implement some kind of altjit-specific cross-arch logic for the mismatched VM case. This change won't help the cross-arch case. Actually, it might be completely broken because a number like "41" might have a completely different interpretation. I guess I should check for mismatched VM for this PR. |
That is, AltJit on same architecture (matching VM) with RunAltJitCode=0.
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ok, I fixed the PR to only apply to same-architecture cases. Cross-arch cases still need a fix. |
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/azp run runtime-coreclr superpmi-replay-apx |
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Azure Pipelines successfully started running 1 pipeline(s). |
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/ba-g unrelated failures |
When running as an AltJit when the generated code will not be used (either because of a mismatched VM, or because RunAltJitCode=0), the JIT overwrites the passed in ISAs. When it does so, it zeros out the VectorT* ISA flags.
Instead of this, carry over the existing ISA flags. This should work for same-architecture SPMI replays.
I'm not sure if additional logic for specifically setting the VectorT* ISA is required for other scenarios, or if incorporating similar logic to
EEJitManager::SetCpuInfo()intoCompiler::compCompile()is required.Adds new JIT debugging helpers
dIsa()anddIsaFlags()to dump out string representations ofCORINFO_InstructionSetandCORINFO_InstructionSetFlags.Fixes #113869