[clang] [clang] CTAD: implement the missing IsDeducible constraint for alias templates (PR #89358)

[via cfe-commits]

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@@ -3307,6 +3341,58 @@ Sema::DeduceTemplateArguments(VarTemplatePartialSpecializationDecl *Partial,
   return ::DeduceTemplateArguments(*this, Partial, TemplateArgs, Info);
 }
 
+TemplateDeductionResult
+Sema::DeduceTemplateArgumentsFromType(TemplateDecl *TD, QualType FromType,
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cor3ntin wrote:

We have a lot of `DeduceTemplateArguments` function so I think we want to add a comment here describing what that function does / when it is used.

https://github.com/llvm/llvm-project/pull/89358