Switch to APFloat constructor taking fltSemantics.

This change also makes the serialisation store the required semantics,
fixing an issue where PPC128 was always assumed when re-reading a
128-bit value.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173139 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Serialization/ASTReaderStmt.cpp b/lib/Serialization/ASTReaderStmt.cpp
index 6735c3c..7f26a17 100644
--- a/lib/Serialization/ASTReaderStmt.cpp
+++ b/lib/Serialization/ASTReaderStmt.cpp
@@ -378,8 +378,10 @@
 
 void ASTStmtReader::VisitFloatingLiteral(FloatingLiteral *E) {
   VisitExpr(E);
-  E->setValue(Reader.getContext(), Reader.ReadAPFloat(Record, Idx));
+  E->setRawSemantics(static_cast<Stmt::APFloatSemantics>(Record[Idx++]));
   E->setExact(Record[Idx++]);
+  E->setValue(Reader.getContext(),
+              Reader.ReadAPFloat(Record, E->getSemantics(), Idx));
   E->setLocation(ReadSourceLocation(Record, Idx));
 }