diff --git a/http_test.go b/http_test.go
index 370e9aa9e5..37b8ce11b8 100644
--- a/http_test.go
+++ b/http_test.go
@@ -7,7 +7,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"math"
 	"mime/multipart"
 	"net/http"
 	"net/http/httptest"
@@ -16,7 +15,6 @@ import (
 	"strings"
 	"testing"
 	"time"
-	"unsafe"
 
 	"github.com/valyala/bytebufferpool"
 )
@@ -1968,34 +1966,6 @@ func testSetResponseBodyStreamChunked(t *testing.T, body string, trailer map[str
 	}
 }
 
-func TestRound2ForSliceCap(t *testing.T) {
-	t.Parallel()
-
-	testRound2ForSliceCap(t, 0, 0)
-	testRound2ForSliceCap(t, 1, 1)
-	testRound2ForSliceCap(t, 2, 2)
-	testRound2ForSliceCap(t, 3, 4)
-	testRound2ForSliceCap(t, 4, 4)
-	testRound2ForSliceCap(t, 5, 8)
-	testRound2ForSliceCap(t, 7, 8)
-	testRound2ForSliceCap(t, 8, 8)
-	testRound2ForSliceCap(t, 9, 16)
-	testRound2ForSliceCap(t, 0x10001, 0x20000)
-
-	if unsafe.Sizeof(int(0)) == 4 {
-		testRound2ForSliceCap(t, math.MaxInt32-1, math.MaxInt32)
-	} else {
-		testRound2ForSliceCap(t, math.MaxInt32, math.MaxInt32)
-		testRound2ForSliceCap(t, math.MaxInt64-1, math.MaxInt64-1)
-	}
-}
-
-func testRound2ForSliceCap(t *testing.T, n, expectedRound2 int) {
-	if roundUpForSliceCap(n) != expectedRound2 {
-		t.Fatalf("Unexpected round2(%d)=%d. Expected %d", n, roundUpForSliceCap(n), expectedRound2)
-	}
-}
-
 func TestRequestReadChunked(t *testing.T) {
 	t.Parallel()
 
diff --git a/round2_32.go b/round2_32.go
index 541b85e216..2990e4211d 100644
--- a/round2_32.go
+++ b/round2_32.go
@@ -3,6 +3,8 @@
 
 package fasthttp
 
+import "math"
+
 func roundUpForSliceCap(n int) int {
 	if n <= 0 {
 		return 0
diff --git a/round2_32_test.go b/round2_32_test.go
new file mode 100644
index 0000000000..1bb2c0dbe7
--- /dev/null
+++ b/round2_32_test.go
@@ -0,0 +1,32 @@
+//go:build !amd64 && !arm64 && !ppc64 && !ppc64le && !s390x
+// +build !amd64,!arm64,!ppc64,!ppc64le,!s390x
+
+package fasthttp
+
+import (
+	"math"
+	"testing"
+)
+
+func TestRound2ForSliceCap(t *testing.T) {
+	t.Parallel()
+
+	testRound2ForSliceCap(t, 0, 0)
+	testRound2ForSliceCap(t, 1, 1)
+	testRound2ForSliceCap(t, 2, 2)
+	testRound2ForSliceCap(t, 3, 4)
+	testRound2ForSliceCap(t, 4, 4)
+	testRound2ForSliceCap(t, 5, 8)
+	testRound2ForSliceCap(t, 7, 8)
+	testRound2ForSliceCap(t, 8, 8)
+	testRound2ForSliceCap(t, 9, 16)
+	testRound2ForSliceCap(t, 0x10001, 0x20000)
+
+	testRound2ForSliceCap(t, math.MaxInt32-1, math.MaxInt32-1)
+}
+
+func testRound2ForSliceCap(t *testing.T, n, expectedRound2 int) {
+	if roundUpForSliceCap(n) != expectedRound2 {
+		t.Fatalf("Unexpected round2(%d)=%d. Expected %d", n, roundUpForSliceCap(n), expectedRound2)
+	}
+}
diff --git a/round2_64_test.go b/round2_64_test.go
new file mode 100644
index 0000000000..d805802ef7
--- /dev/null
+++ b/round2_64_test.go
@@ -0,0 +1,33 @@
+//go:build amd64 || arm64 || ppc64 || ppc64le || s390x
+// +build amd64 arm64 ppc64 ppc64le s390x
+
+package fasthttp
+
+import (
+	"math"
+	"testing"
+)
+
+func TestRound2ForSliceCap(t *testing.T) {
+	t.Parallel()
+
+	testRound2ForSliceCap(t, 0, 0)
+	testRound2ForSliceCap(t, 1, 1)
+	testRound2ForSliceCap(t, 2, 2)
+	testRound2ForSliceCap(t, 3, 4)
+	testRound2ForSliceCap(t, 4, 4)
+	testRound2ForSliceCap(t, 5, 8)
+	testRound2ForSliceCap(t, 7, 8)
+	testRound2ForSliceCap(t, 8, 8)
+	testRound2ForSliceCap(t, 9, 16)
+	testRound2ForSliceCap(t, 0x10001, 0x20000)
+
+	testRound2ForSliceCap(t, math.MaxInt32, math.MaxInt32)
+	testRound2ForSliceCap(t, math.MaxInt64-1, math.MaxInt64-1)
+}
+
+func testRound2ForSliceCap(t *testing.T, n, expectedRound2 int) {
+	if roundUpForSliceCap(n) != expectedRound2 {
+		t.Fatalf("Unexpected round2(%d)=%d. Expected %d", n, roundUpForSliceCap(n), expectedRound2)
+	}
+}