xref: /aosp_15_r20/external/llvm/test/Transforms/InstCombine/invariant.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)
1*9880d681SAndroid Build Coastguard Worker; Test to make sure unused llvm.invariant.start calls are not trivially eliminated
2*9880d681SAndroid Build Coastguard Worker; RUN: opt < %s -instcombine -S | FileCheck %s
3*9880d681SAndroid Build Coastguard Worker
4*9880d681SAndroid Build Coastguard Workerdeclare void @g(i8*)
5*9880d681SAndroid Build Coastguard Worker
6*9880d681SAndroid Build Coastguard Workerdeclare {}* @llvm.invariant.start(i64, i8* nocapture) nounwind readonly
7*9880d681SAndroid Build Coastguard Worker
8*9880d681SAndroid Build Coastguard Workerdefine i8 @f() {
9*9880d681SAndroid Build Coastguard Worker  %a = alloca i8                                  ; <i8*> [#uses=4]
10*9880d681SAndroid Build Coastguard Worker  store i8 0, i8* %a
11*9880d681SAndroid Build Coastguard Worker  %i = call {}* @llvm.invariant.start(i64 1, i8* %a) ; <{}*> [#uses=0]
12*9880d681SAndroid Build Coastguard Worker  ; CHECK: call {}* @llvm.invariant.start
13*9880d681SAndroid Build Coastguard Worker  call void @g(i8* %a)
14*9880d681SAndroid Build Coastguard Worker  %r = load i8, i8* %a                                ; <i8> [#uses=1]
15*9880d681SAndroid Build Coastguard Worker  ret i8 %r
16*9880d681SAndroid Build Coastguard Worker}
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