diff --git a/llvm/utils/gn/secondary/llvm/lib/Target/AArch64/BUILD.gn b/llvm/utils/gn/secondary/llvm/lib/Target/AArch64/BUILD.gn
index 1b21d97ee2d8..fda5320e5925 100644
--- a/llvm/utils/gn/secondary/llvm/lib/Target/AArch64/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/lib/Target/AArch64/BUILD.gn
@@ -18,6 +18,15 @@ tablegen("AArch64GenFastISel") {
   td_file = "AArch64.td"
 }
 
+tablegen("AArch64GenO0PreLegalizeGICombiner") {
+  visibility = [ ":LLVMAArch64CodeGen" ]
+  args = [
+    "-gen-global-isel-combiner",
+    "-combiners=AArch64O0PreLegalizerCombinerHelper",
+  ]
+  td_file = "AArch64.td"
+}
+
 tablegen("AArch64GenGlobalISel") {
   visibility = [ ":LLVMAArch64CodeGen" ]
   args = [ "-gen-global-isel" ]
@@ -70,6 +79,7 @@ static_library("LLVMAArch64CodeGen") {
     ":AArch64GenFastISel",
     ":AArch64GenGlobalISel",
     ":AArch64GenMCPseudoLowering",
+    ":AArch64GenO0PreLegalizeGICombiner",
     ":AArch64GenPostLegalizeGICombiner",
     ":AArch64GenPostLegalizeGILowering",
     ":AArch64GenPreLegalizeGICombiner",
@@ -140,6 +150,7 @@ static_library("LLVMAArch64CodeGen") {
     "GISel/AArch64GlobalISelUtils.cpp",
     "GISel/AArch64InstructionSelector.cpp",
     "GISel/AArch64LegalizerInfo.cpp",
+    "GISel/AArch64O0PreLegalizerCombiner.cpp",
     "GISel/AArch64PostLegalizerCombiner.cpp",
     "GISel/AArch64PostLegalizerLowering.cpp",
     "GISel/AArch64PostSelectOptimize.cpp",