ssa: makeSlice fit int size and check

cl/_testgo/makeslice/in.go

@@ -0,0 +1,56 @@
+package main
+
+func main() {
+}
+
+func init() {
+	var n int = 2
+	buf := make([]int, n, n*2)
+	if len(buf) != 2 || cap(buf) != 4 {
+		panic("error")
+	}
+}
+
+func init() {
+	var n int32 = 2
+	buf := make([]int, n, n*2)
+	if len(buf) != 2 || cap(buf) != 4 {
+		panic("error")
+	}
+}
+
+func init() {
+	defer func() {
+		r := recover()
+		if r == nil {
+			println("must error")
+		}
+	}()
+	var n int = -1
+	buf := make([]int, n)
+	_ = buf
+}
+
+func init() {
+	defer func() {
+		r := recover()
+		if r == nil {
+			println("must error")
+		}
+	}()
+	var n int = 2
+	buf := make([]int, n, n-1)
+	_ = buf
+}
+
+func init() {
+	defer func() {
+		r := recover()
+		if r == nil {
+			println("must error")
+		}
+	}()
+	var n int64 = 1<<63 - 1
+	buf := make([]int, n)
+	_ = buf
+}