[llvm] [libc] [libc] Move printf long double to simple calc (PR #75414)

[Guillaume Chatelet via llvm-commits]

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@@ -27,6 +27,11 @@ namespace LIBC_NAMESPACE::cpp {
 
 template <size_t Bits, bool Signed> struct BigInt {
 
+  // This being hardcoded as 64 is okay because we're using uint64_t as our
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gchatelet wrote:

Can we also add
```
using word_type = uint64_t;
LIBC_INLINE_VAR static constexpr size_t WORD_SIZE = sizeof(word_type) * CHAR_T;
...
cpp::array<word_type, WORDCOUNT> val{};
```

https://github.com/llvm/llvm-project/pull/75414