No clang-analyzer-* checks by default for generated files

Test: make with WITH_TIDY=1 CLANG_ANALYZER_CHECKS=1

Bug: 198098397
Change-Id: I386be0b4ee0fcc1785b2eeb8d1eb26ced68246d7

cc/builder.go

@@ -646,7 +646,7 @@ func transformSourceToObj(ctx android.ModuleContext, subdir string, srcFiles and
 				OrderOnly: pathDeps,
 				Args: map[string]string{
 					"cFlags":    moduleToolingFlags,
-					"tidyFlags": flags.tidyFlags,
+					"tidyFlags": config.TidyFlagsForSrcFile(srcFile, flags.tidyFlags),
 				},
 			})
 		}

cc/config/tidy.go

@@ -106,6 +106,7 @@ type PathBasedTidyCheck struct {
 
 const tidyDefault = "${config.TidyDefaultGlobalChecks}"
 const tidyExternalVendor = "${config.TidyExternalVendorChecks}"
+const tidyDefaultNoAnalyzer = "${config.TidyDefaultGlobalChecks},-clang-analyzer-*"
 
 // This is a map of local path prefixes to the set of default clang-tidy checks
 // to be used.
@@ -139,3 +140,17 @@ func TidyChecksForDir(dir string) string {
 	}
 	return tidyDefault
 }
+
+func TidyFlagsForSrcFile(srcFile android.Path, flags string) string {
+	// Disable clang-analyzer-* checks globally for generated source files
+	// because some of them are too huge. Local .bp files can add wanted
+	// clang-analyzer checks through the tidy_checks property.
+	// Need to do this patch per source file, because some modules
+	// have both generated and organic source files.
+	if _, ok := srcFile.(android.WritablePath); ok {
+		if strings.Contains(flags, tidyDefault) {
+			return strings.ReplaceAll(flags, tidyDefault, tidyDefaultNoAnalyzer)
+		}
+	}
+	return flags
+}