[release/8.0-rc2] JIT: Fix invalid containment of vector broadcasts #92371
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The containment checks for vector broadcasts were missing a size check, meaning that a uint broadcast could contain a ubyte/ushort indirection. That would lead to out-of-bounds reads. Fix #83387
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Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch Issue DetailsBackport of #92333 to release/8.0-rc2 /cc @jakobbotsch Customer ImpactTestingRiskIMPORTANT: If this backport is for a servicing release, please verify that:
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The issue here might be related to #92357, so I am waiting a bit to continue with this backport until we figure out exactly how they relate. Edit: nope, that issue seems related to embedded broadcasts instead. |
jeffschwMSFT
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tannergooding
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Backport of #92333 to release/8.0-rc2
/cc @jakobbotsch
Customer Impact
The JIT may generate bad code for
VectorXYZ<T>.Create(x)wherexis a memory location of smaller size thanT. In that case the JIT may incorrectly read the memory location using the larger typeT.For example,
Vector128<int>.Create(x.ShortField)may generate bad code reading 4 bytes fromShortFieldinstead of just 2. Customer reported in #83387.Testing
Regression test included.
Risk
Low, disables the JIT's containment optimization in the affected cases.