[llvm] [clang] [X86] Add "Ws" constraint and "p" modifier for symbolic address/label reference (PR #77886)

[Phoebe Wang via llvm-commits]

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@@ -5336,6 +5336,7 @@ X86:
   operand in a SSE register. If AVX is also enabled, can also be a 256-bit
   vector operand in an AVX register. If AVX-512 is also enabled, can also be a
   512-bit vector operand in an AVX512 register. Otherwise, an error.
+- ``Ws``: A symbolic reference or label reference.
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phoebewang wrote:

What's the reason to choose `Ws`?

https://github.com/llvm/llvm-project/pull/77886