[clang] [APINotes][BoundsSafety] Upstream API notes format for bounds-safety function parameters (PR #186960)

[Saleem Abdulrasool via cfe-commits]

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@@ -1074,14 +1071,45 @@ void APINotesWriter::Implementation::writeGlobalVariableBlock(
 }
 
 namespace {
+void emitBoundsSafetyInfo(raw_ostream &OS, const BoundsSafetyInfo &BSI) {
+  llvm::support::endian::Writer writer(OS, llvm::endianness::little);
+  uint8_t flags = 0;
+  if (auto kind = BSI.getKind()) {
+    assert((uint8_t)*kind < (1 << 3));
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compnerd wrote:

I'm not sure I like the cast here - it would silently truncate the value.

https://github.com/llvm/llvm-project/pull/186960