diff --git a/llvm/cmake/modules/TableGen.cmake b/llvm/cmake/modules/TableGen.cmake
--- a/llvm/cmake/modules/TableGen.cmake
+++ b/llvm/cmake/modules/TableGen.cmake
@@ -53,15 +53,6 @@
       list(APPEND LLVM_TABLEGEN_FLAGS "-gisel-coverage-file=${LLVM_GISEL_COV_PREFIX}all")
     endif()
   endif()
-  # Comments are only useful for Debug builds. Omit them if the backend
-  # supports it.
-  if (NOT (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" OR
-           uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO"))
-    list(FIND ARGN "-gen-dag-isel" idx)
-    if (NOT idx EQUAL -1)
-      list(APPEND LLVM_TABLEGEN_FLAGS "-omit-comments")
-    endif()
-  endif()
 
   # MSVC can't support long string literals ("long" > 65534 bytes)[1], so if there's
   # a possibility of generated tables being consumed by MSVC, generate arrays of
diff --git a/llvm/utils/TableGen/DAGISelMatcherEmitter.cpp b/llvm/utils/TableGen/DAGISelMatcherEmitter.cpp
--- a/llvm/utils/TableGen/DAGISelMatcherEmitter.cpp
+++ b/llvm/utils/TableGen/DAGISelMatcherEmitter.cpp
@@ -37,7 +37,12 @@
 // To reduce generated source code size.
 static cl::opt<bool> OmitComments("omit-comments",
                                   cl::desc("Do not generate comments"),
-                                  cl::init(false), cl::cat(DAGISelCat));
+#ifdef NDEBUG
+                                  cl::init(true),
+#else
+                                  cl::init(false),
+#endif
+                                  cl::cat(DAGISelCat));
 
 static cl::opt<bool> InstrumentCoverage(
     "instrument-coverage",