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

[Nagraj Gaonkar via cfe-commits]

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@@ -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);
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NagrajMG wrote:

I thought the low word was common, but since we have to combined all the instrinsics under single function, I will change it.
Thanks!

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