[PECOFF][Driver] Add -heap command line option.

llvm-svn: 183622
diff --git a/lld/lib/ReaderWriter/PECOFF/PECOFFTargetInfo.cpp b/lld/lib/ReaderWriter/PECOFF/PECOFFTargetInfo.cpp
index a4c3e7e..e4bdf5a 100644
--- a/lld/lib/ReaderWriter/PECOFF/PECOFFTargetInfo.cpp
+++ b/lld/lib/ReaderWriter/PECOFF/PECOFFTargetInfo.cpp
@@ -30,6 +30,13 @@
     return true;
   }
 
+  if (_heapReserve < _heapCommit) {
+    diagnostics << "Invalid heap size: reserve size must be equal to or "
+                << "greater than commit size, but got "
+                << _heapCommit << " and " << _heapReserve << ".\n";
+    return true;
+  }
+
   _reader = createReaderPECOFF(*this);
   _writer = createWriterPECOFF(*this);
   return false;