[clang] [Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - allow MMX/SSE/AVX2 PSIGN intrinsics to be used in constexpr (PR #163685)

[Simon Pilgrim via cfe-commits]

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@@ -12245,6 +12245,36 @@ bool VectorExprEvaluator::VisitCallExpr(const CallExpr *E) {
     return Success(APValue(ResultElements.data(), ResultElements.size()), E);
   }
 
+  case X86::BI__builtin_ia32_psignb128:
+  case X86::BI__builtin_ia32_psignb256:
+  case X86::BI__builtin_ia32_psignw128:
+  case X86::BI__builtin_ia32_psignw256:
+  case X86::BI__builtin_ia32_psignd128:
+  case X86::BI__builtin_ia32_psignd256: {
+    APValue ASource, BSource;
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RKSimon wrote:

use EvaluateBinOpExpr with callback?

https://github.com/llvm/llvm-project/pull/163685