[clang] [clang-tools-extra] [clang] Improved canonicalization for template specialization types (PR #135119)

[Erich Keane via cfe-commits]

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@@ -168,6 +168,8 @@ class TemplateArgument {
     LLVM_PREFERRED_TYPE(bool)
     unsigned IsDefaulted : 1;
     uintptr_t V;
+    LLVM_PREFERRED_TYPE(bool)
+    unsigned IsCanonicalExpr : 1;
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erichkeane wrote:

Can we put this ABOVE the `V` here?  `uintptr_t` on some platforms has a 64 bit alignment, so there is potentially a ton of padding above `V`.

https://github.com/llvm/llvm-project/pull/135119