xref: /llvm-project/mlir/test/Transforms/inlining-dce.mlir (revision cda6aa78f8e7346382a204306c4d86ffbab99785)
1// RUN: mlir-opt -allow-unregistered-dialect %s -inline -split-input-file | FileCheck %s
2
3// This file tests the callgraph dead code elimination performed by the inliner.
4
5// Function is already dead.
6// CHECK-NOT: func private @dead_function
7func.func private @dead_function() {
8  return
9}
10
11// Function becomes dead after inlining.
12// CHECK-NOT: func private @dead_function_b
13func.func @dead_function_b() {
14  return
15}
16
17// CHECK: func @live_function()
18func.func @live_function() {
19  call @dead_function_b() : () -> ()
20  return
21}
22
23// Same as above, but a transitive example.
24
25// CHECK: func @live_function_b
26func.func @live_function_b() {
27  return
28}
29// CHECK-NOT: func private @dead_function_c
30func.func private @dead_function_c() {
31  call @live_function_b() : () -> ()
32  return
33}
34// CHECK-NOT: func private @dead_function_d
35func.func private @dead_function_d() {
36  call @dead_function_c() : () -> ()
37  call @dead_function_c() : () -> ()
38  return
39}
40// CHECK: func @live_function_c
41func.func @live_function_c() {
42  call @dead_function_c() : () -> ()
43  call @dead_function_d() : () -> ()
44  return
45}
46
47// Function is referenced by non-callable top-level user.
48// CHECK: func private @live_function_d
49func.func private @live_function_d() {
50  return
51}
52
53"live.user"() {use = @live_function_d} : () -> ()
54
55// -----
56
57// This test checks that the inliner can properly handle the deletion of
58// functions in different SCCs that are referenced by calls materialized during
59// canonicalization.
60// CHECK: func @live_function_e
61func.func @live_function_e() {
62  call @dead_function_e() : () -> ()
63  return
64}
65// CHECK-NOT: func @dead_function_e
66func.func private @dead_function_e() -> () {
67  "test.fold_to_call_op"() {callee=@dead_function_f} : () -> ()
68  return
69}
70// CHECK-NOT: func private @dead_function_f
71func.func private @dead_function_f() {
72  return
73}
74