[clang][modules] Strip LLVM options (llvm#75405)

Currently, the dep scanner does not remove LLVM options from the
argument list.
Since LLVM options shouldn't affect the AST, it is safe to remove them
all.

(cherry picked from commit e007551)

Conflicts:
	clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp

Author: ributzka

clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp

@@ -128,6 +128,8 @@ makeCommonInvocationForModuleBuild(CompilerInvocation CI) {
   CI.getFrontendOpts().OutputFile = "-";
   // FIXME: a build system may want to provide a new path.
   CI.getFrontendOpts().IndexUnitOutputPath.clear();
+  // LLVM options are not going to affect the AST
+  CI.getFrontendOpts().LLVMArgs.clear();
 
   // TODO: Figure out better way to set options to their default value.
   CI.getCodeGenOpts().MainFileName.clear();

clang/test/ClangScanDeps/strip-llvm-args.m

@@ -0,0 +1,46 @@
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: sed -e "s|DIR|%/t|g" %t/cdb1.json.template > %t/cdb1.json
+
+// RUN: clang-scan-deps -compilation-database %t/cdb1.json -format experimental-full > %t/result1.txt
+// RUN: FileCheck %s -input-file %t/result1.txt
+
+// CHECK:        "modules": [
+// CHECK-NEXT:     {
+// CHECK:            "command-line": [
+// CHECK-NOT:          "-mllvm"
+// CHECK:            ]
+// CHECK:            "name": "A"
+// CHECK:          }
+// CHECK-NOT:        "name": "A"
+// CHECK:        "translation-units"
+
+//--- cdb1.json.template
+[
+  {
+    "directory": "DIR",
+    "command": "clang -Imodules/A -fmodules -fmodules-cache-path=DIR/module-cache -fimplicit-modules -fimplicit-module-maps -fsyntax-only DIR/t1.m",
+    "file": "DIR/t1.m"
+  },
+  {
+    "directory": "DIR",
+    "command": "clang -Imodules/A -fmodules -fmodules-cache-path=DIR/module-cache -fimplicit-modules -fimplicit-module-maps -mllvm -stackmap-version=2 -fsyntax-only DIR/t2.m",
+    "file": "DIR/t2.m"
+  }
+]
+
+//--- modules/A/module.modulemap
+
+module A {
+  umbrella header "A.h"
+}
+
+//--- modules/A/A.h
+
+typedef int A_t;
+
+//--- t1.m
+@import A;
+
+//--- t2.m
+@import A;