[clang] [analyzer] Retain address space information in getElementRegion (PR #151370)

[Donát Nagy via cfe-commits]

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@@ -1219,6 +1219,16 @@ MemRegionManager::getElementRegion(QualType elementType, NonLoc Idx,
                                    const ASTContext &Ctx) {
   QualType T = Ctx.getCanonicalType(elementType).getUnqualifiedType();
 
+  // The address space must be preserved because some target-specific address
+  // spaces influence the size of the pointer value which is represented by the
+  // element region.
+  LangAS AS = elementType.getAddressSpace();
+  if (AS != LangAS::Default) {
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NagyDonat wrote:

I would prefer keeping the initialization before the `if`, because I feel that limiting the scope of `AS` does not help too much (because this address space handling is clearly separated from the rest of the method + the whole method is not too long), while squeezing the initialization and the `!= LangAS::Default` onto a single line would make it overcrowded and IMO ugly. (There are some cases where limiting the scope is really helpful, but by default I prefer not using init-if.)

However, this is just a bikeshed, so I can recolor it if you want.

https://github.com/llvm/llvm-project/pull/151370