[complex] Teach the other two binary operators on complex numbers (==

and !=) to support mixed complex and real operand types.

This requires removing an assert from SemaChecking, and adding support
both to the constant evaluator and the code generator to synthesize the
imaginary part when needed. This seemed somewhat cleaner than having
just the comparison operators force real-to-complex conversions.

I've added test cases for these operations. I'm really terrified that
there were *no* tests in-tree which exercised this.

This turned up when trying to build R after my change to the complex
type lowering.

llvm-svn: 219570

5 files changed, 106 insertions, 12 deletions

diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index db300c4fec4..532720666bc 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -6780,15 +6780,27 @@ bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
   QualType LHSTy = E->getLHS()->getType();
   QualType RHSTy = E->getRHS()->getType();
 
-  if (LHSTy->isAnyComplexType()) {
-    assert(RHSTy->isAnyComplexType() && "Invalid comparison");
+  if (LHSTy->isAnyComplexType() || RHSTy->isAnyComplexType()) {
     ComplexValue LHS, RHS;
-
-    bool LHSOK = EvaluateComplex(E->getLHS(), LHS, Info);
+    bool LHSOK;
+    if (E->getLHS()->getType()->isRealFloatingType()) {
+      LHSOK = EvaluateFloat(E->getLHS(), LHS.FloatReal, Info);
+      if (LHSOK) {
+        LHS.makeComplexFloat();
+        LHS.FloatImag = APFloat(LHS.FloatReal.getSemantics());
+      }
+    } else {
+      LHSOK = EvaluateComplex(E->getLHS(), LHS, Info);
+    }
     if (!LHSOK && !Info.keepEvaluatingAfterFailure())
       return false;
 
-    if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK)
+    if (E->getRHS()->getType()->isRealFloatingType()) {
+      if (!EvaluateFloat(E->getRHS(), RHS.FloatReal, Info) || !LHSOK)
+        return false;
+      RHS.makeComplexFloat();
+      RHS.FloatImag = APFloat(RHS.FloatReal.getSemantics());
+    } else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK)
       return false;
 
     if (LHS.isComplexFloat()) {
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index abde51f29e4..ac6afe48453 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -2754,6 +2754,7 @@ Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc,
   TestAndClearIgnoreResultAssign();
   Value *Result;
   QualType LHSTy = E->getLHS()->getType();
+  QualType RHSTy = E->getRHS()->getType();
   if (const MemberPointerType *MPT = LHSTy->getAs<MemberPointerType>()) {
     assert(E->getOpcode() == BO_EQ ||
            E->getOpcode() == BO_NE);
@@ -2761,7 +2762,7 @@ Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc,
     Value *RHS = CGF.EmitScalarExpr(E->getRHS());
     Result = CGF.CGM.getCXXABI().EmitMemberPointerComparison(
                    CGF, LHS, RHS, MPT, E->getOpcode() == BO_NE);
-  } else if (!LHSTy->isAnyComplexType()) {
+  } else if (!LHSTy->isAnyComplexType() && !RHSTy->isAnyComplexType()) {
     Value *LHS = Visit(E->getLHS());
     Value *RHS = Visit(E->getRHS());
 
@@ -2849,10 +2850,27 @@ Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc,
 
   } else {
     // Complex Comparison: can only be an equality comparison.
-    CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS());
-    CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS());
-
-    QualType CETy = LHSTy->getAs<ComplexType>()->getElementType();
+    CodeGenFunction::ComplexPairTy LHS, RHS;
+    QualType CETy;
+    if (auto *CTy = LHSTy->getAs<ComplexType>()) {
+      LHS = CGF.EmitComplexExpr(E->getLHS());
+      CETy = CTy->getElementType();
+    } else {
+      LHS.first = Visit(E->getLHS());
+      LHS.second = llvm::Constant::getNullValue(LHS.first->getType());
+      CETy = LHSTy;
+    }
+    if (auto *CTy = RHSTy->getAs<ComplexType>()) {
+      RHS = CGF.EmitComplexExpr(E->getRHS());
+      assert(CGF.getContext().hasSameUnqualifiedType(CETy,
+                                                     CTy->getElementType()) &&
+             "The element types must always match.");
+    } else {
+      RHS.first = Visit(E->getRHS());
+      RHS.second = llvm::Constant::getNullValue(RHS.first->getType());
+      assert(CGF.getContext().hasSameUnqualifiedType(CETy, RHSTy) &&
+             "The element types must always match.");
+    }
 
     Value *ResultR, *ResultI;
     if (CETy->isRealFloatingType()) {
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index a856c98bf05..58c626351f9 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -5890,8 +5890,13 @@ static void AnalyzeImpConvsInComparison(Sema &S, BinaryOperator *E) {
 static void AnalyzeComparison(Sema &S, BinaryOperator *E) {
   // The type the comparison is being performed in.
   QualType T = E->getLHS()->getType();
-  assert(S.Context.hasSameUnqualifiedType(T, E->getRHS()->getType())
-         && "comparison with mismatched types");
+
+  // Only analyze comparison operators where both sides have been converted to
+  // the same type.
+  if (!S.Context.hasSameUnqualifiedType(T, E->getRHS()->getType()))
+    return AnalyzeImpConvsInComparison(S, E);
+
+  // Don't analyze value-dependent comparisons directly.
   if (E->isValueDependent())
     return AnalyzeImpConvsInComparison(S, E);
 
diff --git a/clang/test/CodeGen/complex-math.c b/clang/test/CodeGen/complex-math.c
index ca04e8d94d1..27540c78f77 100644
--- a/clang/test/CodeGen/complex-math.c
+++ b/clang/test/CodeGen/complex-math.c
@@ -367,3 +367,54 @@ long double _Complex div_long_double_cc(long double _Complex a, long double _Com
   // X86: ret
   return a / b;
 }
+
+// Comparison operators don't rely on library calls or have interseting math
+// properties, but test that mixed types work correctly here.
+_Bool eq_float_cr(float _Complex a, float b) {
+  // X86-LABEL: @eq_float_cr(
+  // X86: fcmp oeq
+  // X86: fcmp oeq
+  // X86: and i1
+  // X86: ret
+  return a == b;
+}
+_Bool eq_float_rc(float a, float _Complex b) {
+  // X86-LABEL: @eq_float_rc(
+  // X86: fcmp oeq
+  // X86: fcmp oeq
+  // X86: and i1
+  // X86: ret
+  return a == b;
+}
+_Bool eq_float_cc(float _Complex a, float _Complex b) {
+  // X86-LABEL: @eq_float_cc(
+  // X86: fcmp oeq
+  // X86: fcmp oeq
+  // X86: and i1
+  // X86: ret
+  return a == b;
+}
+_Bool ne_float_cr(float _Complex a, float b) {
+  // X86-LABEL: @ne_float_cr(
+  // X86: fcmp une
+  // X86: fcmp une
+  // X86: or i1
+  // X86: ret
+  return a != b;
+}
+_Bool ne_float_rc(float a, float _Complex b) {
+  // X86-LABEL: @ne_float_rc(
+  // X86: fcmp une
+  // X86: fcmp une
+  // X86: or i1
+  // X86: ret
+  return a != b;
+}
+_Bool ne_float_cc(float _Complex a, float _Complex b) {
+  // X86-LABEL: @ne_float_cc(
+  // X86: fcmp une
+  // X86: fcmp une
+  // X86: or i1
+  // X86: ret
+  return a != b;
+}
diff --git a/clang/test/SemaCXX/complex-folding.cpp b/clang/test/SemaCXX/complex-folding.cpp
index 6a77bfdb310..1c2f9c73eb3 100644
--- a/clang/test/SemaCXX/complex-folding.cpp
+++ b/clang/test/SemaCXX/complex-folding.cpp
@@ -3,6 +3,14 @@
 // Test the constant folding of builtin complex numbers.
 
 static_assert((0.0 + 0.0j) == (0.0 + 0.0j));
+static_assert((0.0 + 0.0j) != (0.0 + 0.0j)); // expected-error {{static_assert}}
+
+static_assert((0.0 + 0.0j) == 0.0);
+static_assert(0.0 == (0.0 + 0.0j));
+static_assert(0.0 == 0.0j);
+static_assert((0.0 + 1.0j) != 0.0);
+static_assert(1.0 != (0.0 + 0.0j));
+static_assert(0.0 != 1.0j);
 
 // Walk around the complex plane stepping between angular differences and
 // equality.