perf: avoid heap allocation in applier findPackage (#7883)

jinroh · knqyf263 · web-flow · commit 9bd6ed73e5d4 · 2024-12-09T12:28:09.000Z
Co-authored-by: knqyf263 &lt;knqyf263@gmail.com&gt;
diff --git a/pkg/fanal/applier/docker.go b/pkg/fanal/applier/docker.go
@@ -31,9 +31,10 @@ type History struct {
 }
 
 func findPackage(e ftypes.Package, s []ftypes.Package) *ftypes.Package {
-	for _, a := range s {
+	for i := range s {
+		a := &s[i] // do not range by value to avoid heap allocations
 		if a.Name == e.Name && a.Version == e.Version && a.Release == e.Release {
-			return &a
+			return a
 		}
 	}
 	return nil

Original file line number	Diff line number	Diff line change
`@@ -31,9 +31,10 @@ type History struct {`
`31`	`31`	`}`
`32`	`32`
`33`	`33`	`func findPackage(e ftypes.Package, s []ftypes.Package) *ftypes.Package {`
`34`		`- for _, a := range s {`
	`34`	`+ for i := range s {`
	`35`	`+ a := &s[i] // do not range by value to avoid heap allocations`
`35`	`36`	`if a.Name == e.Name && a.Version == e.Version && a.Release == e.Release {`
`36`		`- return &a`
	`37`	`+ return a`
`37`	`38`	`}`
`38`	`39`	`}`
`39`	`40`	`return nil`