[Modules] Record side effect info in EvaluatedStmt #11022
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…ntain side effects (llvm#143739)" This reverts commit db18f41.
All deserialized VarDecl initializers are EvaluatedStmt, but not all EvaluatedStmt initializers are from a PCH. Calling `VarDecl::hasInitWithSideEffects` can trigger constant evaluation, but it's hard to know ahead of time whether that will trigger deserialization - even if the initializer is fully deserialized, it may contain a call to a constructor whose body is not deserialized. By caching the result of `VarDecl::hasInitWithSideEffects` and populating that cache during deserialization we can guarantee that calling it won't trigger deserialization regardless of the state of the initializer. This also reduces memory usage by removing the `InitSideEffectVars` set in `ASTReader`. rdar://154717930 (cherry picked from commit 2910c24)
EvaluateAsInitializer does not support evaluating values with dependent types. This was previously guarded with a check for the initializer expression, but it is possible for the VarDecl to have a dependent type without the initializer having a dependent type, when the initializer is a specialized template type and the VarDecl has the unspecialized type. This adds a guard checking for dependence in the VarDecl type as well. This fixes the issue raised by Google in llvm#145447 (cherry picked from commit c885005)
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All deserialized VarDecl initializers are EvaluatedStmt, but not all EvaluatedStmt initializers are from a PCH. Calling VarDecl::hasInitWithSideEffects can trigger constant evaluation, but it's hard to know ahead of time whether that will trigger deserialization - even if the initializer is fully deserialized, it may contain a call to a constructor whose body is not deserialized. By caching the result of VarDecl::hasInitWithSideEffects and populating that cache during deserialization we can guarantee that calling it won't trigger deserialization regardless of the state of the initializer. This also reduces memory usage by removing the InitSideEffectVars set in ASTReader.
rdar://154717930
(cherry picked from commit 2910c24)