[clang] [CLANG] Full support of complex multiplication and division. (PR #81514)

[Andy Kaylor via cfe-commits]

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@@ -986,13 +1028,17 @@ ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
     llvm::Value *OrigLHSi = LHSi;
     if (!LHSi)
       LHSi = llvm::Constant::getNullValue(RHSi->getType());
-    if (Op.FPFeatures.getComplexRange() == LangOptions::CX_Fortran)
+    QualType ComplexElementTy = Op.Ty->castAs<ComplexType>()->getElementType();
+    if (Op.FPFeatures.getComplexRange() == LangOptions::CX_Improved ||
+        (Op.FPFeatures.getComplexRange() == LangOptions::CX_Promoted &&
+         FPHasBeenPromoted == LangOptions::CX_Improved))
       return EmitRangeReductionDiv(LHSr, LHSi, RHSr, RHSi);
-    else if (Op.FPFeatures.getComplexRange() == LangOptions::CX_Limited)
+    else if (Op.FPFeatures.getComplexRange() == LangOptions::CX_Basic ||
+             Op.FPFeatures.getComplexRange() == LangOptions::CX_Promoted)
       return EmitAlgebraicDiv(LHSr, LHSi, RHSr, RHSi);
     else if (!CGF.getLangOpts().FastMath ||
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andykaylor wrote:

I think we should remove the fast-math check here. The driver handling of fast-math sets the complex arithmetic option. This check has always been problematic because disabling just one component of fast-math (such as enabling signed zeros) causes this to be false.

https://github.com/llvm/llvm-project/pull/81514