[clang] [X86] Allow PSHUFD/PSHUFLW/PSHUFW intrinsics in constexpr. (PR #161210)

[Timm Baeder via cfe-commits]

================
@@ -3417,6 +3629,39 @@ bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const CallExpr *Call,
     return interp__builtin_elementwise_int_binop(S, OpPC, Call,
                                                  llvm::APIntOps::mulhs);
 
+  case clang::X86::BI__builtin_ia32_pshuflw:
+  case clang::X86::BI__builtin_ia32_pshuflw256:
+  case clang::X86::BI__builtin_ia32_pshuflw512:
+  case clang::X86::BI__builtin_ia32_pshuflw128_mask:
+  case clang::X86::BI__builtin_ia32_pshuflw256_mask:
+  case clang::X86::BI__builtin_ia32_pshuflw512_mask:
+  case clang::X86::BI__builtin_ia32_pshuflw128_maskz:
+  case clang::X86::BI__builtin_ia32_pshuflw256_maskz:
+  case clang::X86::BI__builtin_ia32_pshuflw512_maskz:
+    return interp__builtin_ia32_pshuflw_common(S, OpPC, Call);
----------------
tbaederr wrote:

What is "common" about these three functions?

https://github.com/llvm/llvm-project/pull/161210