diff --git a/SPIRV/GlslangToSpv.cpp b/SPIRV/GlslangToSpv.cpp
index 37ee52f..3dffceb 100755
--- a/SPIRV/GlslangToSpv.cpp
+++ b/SPIRV/GlslangToSpv.cpp
@@ -2526,14 +2526,21 @@
     // Sort out the operands
     //  - mapping from glslang -> SPV
     //  - there are extra SPV operands with no glslang source
+    //  - compare-exchange swaps the value and comparator
+    //  - compare-exchange has an extra memory semantics
     std::vector<spv::Id> spvAtomicOperands;  // hold the spv operands
     auto opIt = operands.begin();            // walk the glslang operands
     spvAtomicOperands.push_back(*(opIt++));
     spvAtomicOperands.push_back(builder.makeUintConstant(spv::ScopeDevice));     // TBD: what is the correct scope?
     spvAtomicOperands.push_back(builder.makeUintConstant(spv::MemorySemanticsMaskNone)); // TBD: what are the correct memory semantics?
+    if (opCode == spv::OpAtomicCompareExchange) {
+        spvAtomicOperands.push_back(builder.makeUintConstant(spv::MemorySemanticsMaskNone)); // TBD: what are the correct memory semantics?
+        spvAtomicOperands.push_back(*(opIt + 1));
+        spvAtomicOperands.push_back(*opIt);
+        opIt += 2;
+    }
 
-    // Add the rest of the operands, skipping the first one, which was dealt with above.
-    // For some ops, there are none, for some 1, for compare-exchange, 2.
+    // Add the rest of the operands, skipping any that were dealt with above.
     for (; opIt != operands.end(); ++opIt)
         spvAtomicOperands.push_back(*opIt);