[libc-commits] [PATCH] D152459: [libc] Add Int<> type and fix (U)Int<128> compatibility issues.

[Tue Ly via Phabricator via libc-commits]

lntue added inline comments.


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Comment at: libc/test/src/math/TruncTest.h:68
     constexpr UIntType COUNT = 100'000;
-    constexpr UIntType STEP = UIntType(-1) / COUNT;
+    const UIntType STEP = UIntType(-1) / COUNT;
     for (UIntType i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
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sivachandra wrote:
> lntue wrote:
> > sivachandra wrote:
> > > I did not do a detailed review but why were these `constexpr` decls converted to `const` decls?
> > Because these use the division operator, which using `clz()` internally, which in turn calls `__builtin_clz*` that are not `constexpr`.
> We should be able to implement `cpp::is_constant_evaluated` using `__builtin_is_constant_evaluated` and use it to retain the `constexpr` nature where relevant. We should ideally do that first before adding `BigInt`.
Turns out that `__builtin_clz*` are already `constexpr`, so marking all our `clz` functions `constexpr` is enough.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D152459/new/

https://reviews.llvm.org/D152459