[clang] [X86][Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - allow SSE/AVX COMI/UCOMI/CMPS/CMPP fp comparison intrinsics to be used in constexpr (PR #182589)

[Simon Pilgrim via cfe-commits]

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@@ -15,22 +15,71 @@
 #define LLVM_CLANG_LIB_AST_EXPRCONSTSHARED_H
 
 #include "clang/Basic/BuiltinTraits.h"
+#include "llvm/ADT/APFloat.h"
 #include <cstdint>
 #include <optional>
 
 namespace llvm {
 class APFloat;
 class APSInt;
 class APInt;
-}
+} // namespace llvm
+
 namespace clang {
 class QualType;
 class LangOptions;
 class ASTContext;
 class CharUnits;
 class Expr;
+
+// SSE/AVX floating-point comparison immediates
+namespace X86CmpImm {
+constexpr uint32_t CMP_EQ_OQ = 0x00; // Equal (ordered, quiet)
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RKSimon wrote:

would an enum be better?

https://github.com/llvm/llvm-project/pull/182589