xref: /llvm-project/llvm/test/Transforms/LICM/promote-unknown-load.ll (revision 88419a30a02de3a35db990399315b0b3e329627e)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -S -passes=licm < %s | FileCheck %s
3
4; The %val.ptr load might alias the %pos.ptr load/stores, but it's still
5; fine to promote the load as long as the store is retained.
6define i32 @test(ptr %ary, i64 %len) {
7; CHECK-LABEL: @test(
8; CHECK-NEXT:  entry:
9; CHECK-NEXT:    [[POS_PTR:%.*]] = getelementptr i8, ptr [[ARY:%.*]], i64 32
10; CHECK-NEXT:    [[POS_PTR_PROMOTED:%.*]] = load i64, ptr [[POS_PTR]], align 4
11; CHECK-NEXT:    br label [[LOOP:%.*]]
12; CHECK:       loop:
13; CHECK-NEXT:    [[POS_NEXT1:%.*]] = phi i64 [ [[POS_PTR_PROMOTED]], [[ENTRY:%.*]] ], [ [[POS_NEXT:%.*]], [[LOOP]] ]
14; CHECK-NEXT:    [[ACCUM:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[ACCUM_NEXT:%.*]], [[LOOP]] ]
15; CHECK-NEXT:    [[POS_NEXT]] = add i64 [[POS_NEXT1]], 1
16; CHECK-NEXT:    store i64 [[POS_NEXT]], ptr [[POS_PTR]], align 4
17; CHECK-NEXT:    [[VAL_PTR:%.*]] = getelementptr i32, ptr [[ARY]], i64 [[POS_NEXT1]]
18; CHECK-NEXT:    [[VAL:%.*]] = load i32, ptr [[VAL_PTR]], align 4
19; CHECK-NEXT:    [[ACCUM_NEXT]] = add i32 [[ACCUM]], [[VAL]]
20; CHECK-NEXT:    [[EXIT_COND:%.*]] = icmp ult i64 [[POS_NEXT1]], [[LEN:%.*]]
21; CHECK-NEXT:    br i1 [[EXIT_COND]], label [[LOOP]], label [[EXIT:%.*]]
22; CHECK:       exit:
23; CHECK-NEXT:    [[ACCUM_LCSSA:%.*]] = phi i32 [ [[ACCUM]], [[LOOP]] ]
24; CHECK-NEXT:    ret i32 [[ACCUM_LCSSA]]
25;
26entry:
27  %pos.ptr = getelementptr i8, ptr %ary, i64 32
28  br label %loop
29
30loop:
31  %accum = phi i32 [ 0, %entry ], [ %accum.next, %loop ]
32  %pos = load i64, ptr %pos.ptr
33  %pos.next = add i64 %pos, 1
34  store i64 %pos.next, ptr %pos.ptr
35  %val.ptr = getelementptr i32, ptr %ary, i64 %pos
36  %val = load i32, ptr %val.ptr
37  %accum.next = add i32 %accum, %val
38  %exit.cond = icmp ult i64 %pos, %len
39  br i1 %exit.cond, label %loop, label %exit
40
41exit:
42  ret i32 %accum
43}
44