xref: /llvm-project/llvm/test/Transforms/NaryReassociate/pr24301.ll (revision 63691eef9ba7f0e54448ec7ccdd27ef23fea4ddd)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=nary-reassociate -S | FileCheck %s
3; RUN: opt < %s -passes='nary-reassociate' -S | FileCheck %s
4
5define i32 @foo(i32 %t4) {
6; CHECK-LABEL: @foo(
7; CHECK-NEXT:  entry:
8; CHECK-NEXT:    [[T13:%.*]] = add i32 [[T4:%.*]], -128
9; CHECK-NEXT:    [[T14:%.*]] = add i32 [[T13]], 8
10; CHECK-NEXT:    [[T23:%.*]] = add i32 [[T13]], 119
11; CHECK-NEXT:    ret i32 [[T23]]
12;
13entry:
14  %t5 = add i32 %t4, 8
15  %t13 = add i32 %t4, -128  ; deleted
16  %t14 = add i32 %t13, 8    ; => %t5 + -128
17  %t21 = add i32 119, %t4
18  ; do not rewrite %t23 against %t13 because %t13 is already deleted
19  %t23 = add i32 %t21, -128
20  ret i32 %t23
21}
22
23; This is essentially the same test as the previous one but intermidiate result (t14) has a use.
24define i32 @foo2(i32 %t4) {
25; CHECK-LABEL: @foo2(
26; CHECK-NEXT:  entry:
27; CHECK-NEXT:    [[T13:%.*]] = add i32 [[T4:%.*]], -128
28; CHECK-NEXT:    [[T14:%.*]] = add i32 [[T13]], 8
29; CHECK-NEXT:    [[T23:%.*]] = add i32 [[T13]], 119
30; CHECK-NEXT:    [[RES:%.*]] = add i32 [[T14]], [[T23]]
31; CHECK-NEXT:    ret i32 [[RES]]
32;
33entry:
34  %t5 = add i32 %t4, 8     ; initially dead
35  %t13 = add i32 %t4, -128
36  %t14 = add i32 %t13, 8
37  %t21 = add i32 119, %t4  ; => dead after reassociation
38  %t23 = add i32 %t21, -128; => reassociated to t13 + 119
39  %res = add i32 %t14, %t23
40  ret i32 %res
41}
42