[llvm] [Arm64EC] Copy import descriptors to the EC Map (PR #84834)

[Eli Friedman via llvm-commits]

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@@ -677,6 +677,16 @@ static bool isECObject(object::SymbolicFile &Obj) {
   return false;
 }
 
+bool isImportDescriptor(const std::string_view Name) {
+  return Name.substr(0, ImportDescriptorPrefix.size()) ==
+             ImportDescriptorPrefix ||
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efriedma-quic wrote:

llvm::StringRef, the LLVM equivalent to string_view, is used widely all over LLVM, has various convenient methods here, like starts_with()/ends_with().  I don't think it's worth switching to the std version at the cost of readability.  (Maybe LLVM will revisit the general usage of StringRef at some point, but likely not soon.)

https://github.com/llvm/llvm-project/pull/84834