diff --git a/clang/lib/CIR/CodeGen/CIRGenModule.cpp b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
index eef23a0ebda7f..c977ff9f06de6 100644
--- a/clang/lib/CIR/CodeGen/CIRGenModule.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
@@ -119,6 +119,19 @@ CIRGenModule::CIRGenModule(mlir::MLIRContext &mlirContext,
                        cir::OptInfoAttr::get(&mlirContext,
                                              cgo.OptimizationLevel,
                                              cgo.OptimizeSize));
+  // Set the module name to be the name of the main file. TranslationUnitDecl
+  // often contains invalid source locations and isn't a reliable source for the
+  // module location.
+  FileID mainFileId = astContext.getSourceManager().getMainFileID();
+  const FileEntry &mainFile =
+      *astContext.getSourceManager().getFileEntryForID(mainFileId);
+  StringRef path = mainFile.tryGetRealPathName();
+  if (!path.empty()) {
+    theModule.setSymName(path);
+    theModule->setLoc(mlir::FileLineColLoc::get(&mlirContext, path,
+                                                /*line=*/0,
+                                                /*column=*/0));
+  }
 }
 
 CIRGenModule::~CIRGenModule() = default;
diff --git a/clang/test/CIR/CodeGen/lang-c-cpp.cpp b/clang/test/CIR/CodeGen/lang-c-cpp.cpp
index e126932104de2..893178384b472 100644
--- a/clang/test/CIR/CodeGen/lang-c-cpp.cpp
+++ b/clang/test/CIR/CodeGen/lang-c-cpp.cpp
@@ -3,8 +3,8 @@
 // RUN: %clang_cc1 -x c -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o %t.c.cir
 // RUN: FileCheck --check-prefix=CIR-C --input-file=%t.c.cir %s
 
-// CIR-CPP: module attributes {{{.*}}cir.lang = #cir.lang<cxx>{{.*}}}
-// CIR-C: module attributes {{{.*}}cir.lang = #cir.lang<c>{{.*}}}
+// CIR-CPP: module{{.*}} attributes {{{.*}}cir.lang = #cir.lang<cxx>{{.*}}}
+// CIR-C: module{{.*}} attributes {{{.*}}cir.lang = #cir.lang<c>{{.*}}}
 
 int main() {
   return 0;
diff --git a/clang/test/CIR/CodeGen/module-filename.cpp b/clang/test/CIR/CodeGen/module-filename.cpp
new file mode 100644
index 0000000000000..05e2e929e3238
--- /dev/null
+++ b/clang/test/CIR/CodeGen/module-filename.cpp
@@ -0,0 +1,11 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o %t.cir
+// RUN: FileCheck --check-prefix=CIR --input-file=%t.cir %s
+
+// Normally, we try to avoid checking the filename of a test, but that's the
+// entire point of this test, so we use a wildcard for the path but check the
+// filename.
+// CIR: module @"{{.*}}module-filename.cpp"
+
+int main() {
+  return 0;
+}
diff --git a/clang/test/CIR/CodeGen/opt-info-attr.cpp b/clang/test/CIR/CodeGen/opt-info-attr.cpp
index 444286b8db8a9..97071d7ac2b2b 100644
--- a/clang/test/CIR/CodeGen/opt-info-attr.cpp
+++ b/clang/test/CIR/CodeGen/opt-info-attr.cpp
@@ -13,10 +13,10 @@
 
 void f() {}
 
-// CHECK-O0: module attributes
+// CHECK-O0: module{{.*}} attributes
 // CHECK-O0-NOT: cir.opt_info
-// CHECK-O1: module attributes {{.+}}cir.opt_info = #cir.opt_info<level = 1, size = 0>{{.+}}
-// CHECK-O2: module attributes {{.+}}cir.opt_info = #cir.opt_info<level = 2, size = 0>{{.+}}
-// CHECK-O3: module attributes {{.+}}cir.opt_info = #cir.opt_info<level = 3, size = 0>{{.+}}
-// CHECK-Os: module attributes {{.+}}cir.opt_info = #cir.opt_info<level = 2, size = 1>{{.+}}
-// CHECK-Oz: module attributes {{.+}}cir.opt_info = #cir.opt_info<level = 2, size = 2>{{.+}}
+// CHECK-O1: module{{.*}} attributes {{.+}}cir.opt_info = #cir.opt_info<level = 1, size = 0>{{.+}}
+// CHECK-O2: module{{.*}} attributes {{.+}}cir.opt_info = #cir.opt_info<level = 2, size = 0>{{.+}}
+// CHECK-O3: module{{.*}} attributes {{.+}}cir.opt_info = #cir.opt_info<level = 3, size = 0>{{.+}}
+// CHECK-Os: module{{.*}} attributes {{.+}}cir.opt_info = #cir.opt_info<level = 2, size = 1>{{.+}}
+// CHECK-Oz: module{{.*}} attributes {{.+}}cir.opt_info = #cir.opt_info<level = 2, size = 2>{{.+}}