Make IgnoreParens() look through ChooseExprs.

This is the same way GenericSelectionExpr works, and it's generally a
more consistent approach.

A large part of this patch is devoted to caching the value of the condition
of a ChooseExpr; it's needed to avoid threading an ASTContext into
IgnoreParens().

Fixes <rdar://problem/14438917>.

llvm-svn: 186738

3 files changed, 24 insertions, 3 deletions

diff --git a/clang/lib/Sema/SemaExceptionSpec.cpp b/clang/lib/Sema/SemaExceptionSpec.cpp
index 0385c7783e3..0d662c8f393 100644
--- a/clang/lib/Sema/SemaExceptionSpec.cpp
+++ b/clang/lib/Sema/SemaExceptionSpec.cpp
@@ -1025,7 +1025,7 @@ CanThrowResult Sema::canThrow(const Expr *E) {
   case Expr::ChooseExprClass:
     if (E->isTypeDependent() || E->isValueDependent())
       return CT_Dependent;
-    return canThrow(cast<ChooseExpr>(E)->getChosenSubExpr(Context));
+    return canThrow(cast<ChooseExpr>(E)->getChosenSubExpr());
 
   case Expr::GenericSelectionExprClass:
     if (cast<GenericSelectionExpr>(E)->isResultDependent())
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index f397c5bb2ef..2c933147f44 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -9868,6 +9868,7 @@ ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
   ExprObjectKind OK = OK_Ordinary;
   QualType resType;
   bool ValueDependent = false;
+  bool CondIsTrue = false;
   if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) {
     resType = Context.DependentTy;
     ValueDependent = true;
@@ -9880,9 +9881,10 @@ ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
     if (CondICE.isInvalid())
       return ExprError();
     CondExpr = CondICE.take();
+    CondIsTrue = condEval.getZExtValue();
 
     // If the condition is > zero, then the AST type is the same as the LSHExpr.
-    Expr *ActiveExpr = condEval.getZExtValue() ? LHSExpr : RHSExpr;
+    Expr *ActiveExpr = CondIsTrue ? LHSExpr : RHSExpr;
 
     resType = ActiveExpr->getType();
     ValueDependent = ActiveExpr->isValueDependent();
@@ -9891,7 +9893,7 @@ ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
   }
 
   return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr,
-                                        resType, VK, OK, RPLoc,
+                                        resType, VK, OK, RPLoc, CondIsTrue,
                                         resType->isDependentType(),
                                         ValueDependent));
 }
diff --git a/clang/lib/Sema/SemaPseudoObject.cpp b/clang/lib/Sema/SemaPseudoObject.cpp
index a10612a8b07..106250fe0f5 100644
--- a/clang/lib/Sema/SemaPseudoObject.cpp
+++ b/clang/lib/Sema/SemaPseudoObject.cpp
@@ -101,6 +101,25 @@ namespace {
                                                     resultIndex);
       }
 
+      if (ChooseExpr *ce = dyn_cast<ChooseExpr>(e)) {
+        assert(!ce->isConditionDependent());
+
+        Expr *LHS = ce->getLHS(), *RHS = ce->getRHS();
+        Expr *&rebuiltExpr = ce->isConditionTrue() ? LHS : RHS;
+        rebuiltExpr = rebuild(rebuiltExpr);
+
+        return new (S.Context) ChooseExpr(ce->getBuiltinLoc(),
+                                          ce->getCond(),
+                                          LHS, RHS,
+                                          rebuiltExpr->getType(),
+                                          rebuiltExpr->getValueKind(),
+                                          rebuiltExpr->getObjectKind(),
+                                          ce->getRParenLoc(),
+                                          ce->isConditionTrue(),
+                                          rebuiltExpr->isTypeDependent(),
+                                          rebuiltExpr->isValueDependent());
+      }
+
       llvm_unreachable("bad expression to rebuild!");
     }
   };