PR7884: Fix the implementations of __real__ and __imag__ on real floats.

llvm-svn: 111080

2 files changed, 27 insertions, 11 deletions

diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 3ef2a62e2d7..3b288ec8b7f 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -1842,18 +1842,30 @@ bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
 }
 
 bool FloatExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
-  ComplexValue CV;
-  if (!EvaluateComplex(E->getSubExpr(), CV, Info))
-    return false;
-  Result = CV.FloatReal;
-  return true;
+  if (E->getSubExpr()->getType()->isAnyComplexType()) {
+    ComplexValue CV;
+    if (!EvaluateComplex(E->getSubExpr(), CV, Info))
+      return false;
+    Result = CV.FloatReal;
+    return true;
+  }
+
+  return Visit(E->getSubExpr());
 }
 
 bool FloatExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
-  ComplexValue CV;
-  if (!EvaluateComplex(E->getSubExpr(), CV, Info))
-    return false;
-  Result = CV.FloatImag;
+  if (E->getSubExpr()->getType()->isAnyComplexType()) {
+    ComplexValue CV;
+    if (!EvaluateComplex(E->getSubExpr(), CV, Info))
+      return false;
+    Result = CV.FloatImag;
+    return true;
+  }
+
+  if (!E->getSubExpr()->isEvaluatable(Info.Ctx))
+    Info.EvalResult.HasSideEffects = true;
+  const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(E->getType());
+  Result = llvm::APFloat::getZero(Sem);
   return true;
 }
 
diff --git a/clang/test/Sema/const-eval.c b/clang/test/Sema/const-eval.c
index 9c537250a93..42097e75f31 100644
--- a/clang/test/Sema/const-eval.c
+++ b/clang/test/Sema/const-eval.c
@@ -74,5 +74,9 @@ const _Bool constbool = 0;
 EVAL_EXPR(35, constbool)
 EVAL_EXPR(36, constbool)
 
-EVAL_EXPR(37, (1,2.0) == 2.0)
-EVAL_EXPR(38, __builtin_expect(1,1) == 1)
+EVAL_EXPR(37, (1,2.0) == 2.0 ? 1 : -1)
+EVAL_EXPR(38, __builtin_expect(1,1) == 1 ? 1 : -1)
+
+// PR7884
+EVAL_EXPR(39, __real__(1.f) == 1 ? 1 : -1)
+EVAL_EXPR(40, __imag__(1.f) == 0 ? 1 : -1)