--- /dev/null
+; RUN: opt -passes=argpromotion -mtriple=bpf-pc-linux -S %s | FileCheck %s
+; Source:
+; struct t {
+; int a, b, c, d, e, f, g;
+; };
+; __attribute__((noinline)) static int foo1(struct t *p1, struct t *p2, struct t *p3) {
+; return p1->a + p1->b + p2->c + p2->e + p3->f + p3->g;
+; }
+; __attribute__((noinline)) static int foo2(struct t *p1, struct t *p2, struct t *p3) {
+; return p1->a + p1->b + p2->c + p2->e + p3->f;
+; }
+; void init(void *);
+; int bar(void) {
+; struct t v1, v2, v3;
+; init(&v1); init(&v2); init(&v3);
+; return foo1(&v1, &v2, &v3) + foo2(&v1, &v2, &v3);
+; }
+; Compilation flag:
+; clang -target bpf -O2 -S t.c -mllvm -print-before=argpromotion -mllvm -print-module-scope
+; and then do some manual tailoring to remove some attributes/metadata which is not used
+; by argpromotion pass.
+
+%struct.t = type { i32, i32, i32, i32, i32, i32, i32 }
+
+define i32 @bar() {
+entry:
+ %v1 = alloca %struct.t, align 4
+ %v2 = alloca %struct.t, align 4
+ %v3 = alloca %struct.t, align 4
+ call void @init(ptr noundef nonnull %v1)
+ call void @init(ptr noundef nonnull %v2)
+ call void @init(ptr noundef nonnull %v3)
+ %call = call fastcc i32 @foo1(ptr noundef nonnull %v1, ptr noundef nonnull %v2, ptr noundef nonnull %v3)
+ %call1 = call fastcc i32 @foo2(ptr noundef nonnull %v1, ptr noundef nonnull %v2, ptr noundef nonnull %v3)
+ %add = add nsw i32 %call, %call1
+ ret i32 %add
+}
+
+declare void @init(ptr noundef)
+
+define internal i32 @foo1(ptr nocapture noundef readonly %p1, ptr nocapture noundef readonly %p2, ptr nocapture noundef readonly %p3) {
+entry:
+ %0 = load i32, ptr %p1, align 4
+ %b = getelementptr inbounds %struct.t, ptr %p1, i64 0, i32 1
+ %1 = load i32, ptr %b, align 4
+ %add = add nsw i32 %1, %0
+ %c = getelementptr inbounds %struct.t, ptr %p2, i64 0, i32 2
+ %2 = load i32, ptr %c, align 4
+ %add1 = add nsw i32 %add, %2
+ %e = getelementptr inbounds %struct.t, ptr %p2, i64 0, i32 4
+ %3 = load i32, ptr %e, align 4
+ %add2 = add nsw i32 %add1, %3
+ %f = getelementptr inbounds %struct.t, ptr %p3, i64 0, i32 5
+ %4 = load i32, ptr %f, align 4
+ %add3 = add nsw i32 %add2, %4
+ %g = getelementptr inbounds %struct.t, ptr %p3, i64 0, i32 6
+ %5 = load i32, ptr %g, align 4
+ %add4 = add nsw i32 %add3, %5
+ ret i32 %add4
+}
+
+; Without number-of-argument constraint, argpromotion will create a function signature with 6 arguments. Since
+; bpf target only supports maximum 5 arguments, so no argpromotion here.
+;
+; CHECK: i32 @foo1(ptr nocapture noundef readonly %p1, ptr nocapture noundef readonly %p2, ptr nocapture noundef readonly %p3)
+
+define internal i32 @foo2(ptr noundef %p1, ptr noundef %p2, ptr noundef %p3) {
+entry:
+ %0 = load i32, ptr %p1, align 4
+ %b = getelementptr inbounds %struct.t, ptr %p1, i64 0, i32 1
+ %1 = load i32, ptr %b, align 4
+ %add = add nsw i32 %0, %1
+ %c = getelementptr inbounds %struct.t, ptr %p2, i64 0, i32 2
+ %2 = load i32, ptr %c, align 4
+ %add1 = add nsw i32 %add, %2
+ %e = getelementptr inbounds %struct.t, ptr %p2, i64 0, i32 4
+ %3 = load i32, ptr %e, align 4
+ %add2 = add nsw i32 %add1, %3
+ %f = getelementptr inbounds %struct.t, ptr %p3, i64 0, i32 5
+ %4 = load i32, ptr %f, align 4
+ %add3 = add nsw i32 %add2, %4
+ ret i32 %add3
+}
+
+; Without number-of-argument constraint, argpromotion will create a function signature with 5 arguments, which equals
+; the maximum number of argument permitted by bpf backend, so argpromotion result code does work.
+;
+; CHECK: i32 @foo2(i32 %p1.0.val, i32 %p1.4.val, i32 %p2.8.val, i32 %p2.16.val, i32 %p3.20.val)