[clang] [llvm] [SPIRV] Add support for the `SPV_EXT_long_vector` extension (PR #210279)

[Marcos Maronas via cfe-commits]

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@@ -6578,6 +6633,7 @@ bool SPIRVInstructionSelector::selectFirstBitSet64(
   // algoritm below converts i64 -> i32x2 and i64x4 -> i32x8 it can only
   // operate on vectors with 2 or less components. When largers vectors are
   // seen. Split them, recurse, then recombine them.
+  // TODO: handle the case where SPV_EXT_long_vector is enabled.
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maarquitos14 wrote:

Are we planning to do this on this PR? Otherwise, should we open an issue?

https://github.com/llvm/llvm-project/pull/210279