xref: /llvm-project/llvm/test/Transforms/InstCombine/invariant.ll (revision 4ab40eca080965c65802710e39adbb78c4ce7bde)
1; Test to make sure unused llvm.invariant.start calls are not trivially eliminated
2; RUN: opt < %s -passes=instcombine -S | FileCheck %s
3
4declare void @g(ptr)
5declare void @g_addr1(ptr addrspace(1))
6
7declare ptr @llvm.invariant.start.p0(i64, ptr nocapture) nounwind readonly
8declare ptr @llvm.invariant.start.p1(i64, ptr addrspace(1) nocapture) nounwind readonly
9
10define i8 @f() {
11  %a = alloca i8                                  ; <ptr> [#uses=4]
12  store i8 0, ptr %a
13  %i = call ptr @llvm.invariant.start.p0(i64 1, ptr %a) ; <ptr> [#uses=0]
14  ; CHECK: call ptr @llvm.invariant.start.p0
15  call void @g(ptr %a)
16  %r = load i8, ptr %a                                ; <i8> [#uses=1]
17  ret i8 %r
18}
19
20; make sure llvm.invariant.call in non-default addrspace are also not eliminated.
21define i8 @f_addrspace1(ptr addrspace(1) %a) {
22  store i8 0, ptr addrspace(1) %a
23  %i = call ptr @llvm.invariant.start.p1(i64 1, ptr addrspace(1) %a) ; <ptr> [#uses=0]
24  ; CHECK: call ptr @llvm.invariant.start.p1
25  call void @g_addr1(ptr addrspace(1) %a)
26  %r = load i8, ptr addrspace(1) %a                                ; <i8> [#uses=1]
27  ret i8 %r
28}
29