xref: /aosp_15_r20/external/llvm/test/Transforms/SimplifyCFG/PhiEliminate.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)
1*9880d681SAndroid Build Coastguard Worker; Test a bunch of cases where the cfg simplification code should
2*9880d681SAndroid Build Coastguard Worker; be able to fold PHI nodes into computation in common cases.  Folding the PHI
3*9880d681SAndroid Build Coastguard Worker; nodes away allows the branches to be eliminated, performing a simple form of
4*9880d681SAndroid Build Coastguard Worker; 'if conversion'.
5*9880d681SAndroid Build Coastguard Worker
6*9880d681SAndroid Build Coastguard Worker; RUN: opt < %s -simplifycfg -S > %t.xform
7*9880d681SAndroid Build Coastguard Worker; RUN:   not grep phi %t.xform
8*9880d681SAndroid Build Coastguard Worker; RUN:   grep ret %t.xform
9*9880d681SAndroid Build Coastguard Worker
10*9880d681SAndroid Build Coastguard Workerdeclare void @use(i1)
11*9880d681SAndroid Build Coastguard Worker
12*9880d681SAndroid Build Coastguard Workerdeclare void @use.upgrd.1(i32)
13*9880d681SAndroid Build Coastguard Worker
14*9880d681SAndroid Build Coastguard Worker
15*9880d681SAndroid Build Coastguard Workerdefine void @test(i1 %c, i32 %V, i32 %V2) {
16*9880d681SAndroid Build Coastguard Worker; <label>:0
17*9880d681SAndroid Build Coastguard Worker        br i1 %c, label %T, label %F
18*9880d681SAndroid Build Coastguard WorkerT:              ; preds = %0
19*9880d681SAndroid Build Coastguard Worker        br label %F
20*9880d681SAndroid Build Coastguard WorkerF:              ; preds = %T, %0
21*9880d681SAndroid Build Coastguard Worker        %B1 = phi i1 [ true, %0 ], [ false, %T ]                ; <i1> [#uses=1]
22*9880d681SAndroid Build Coastguard Worker        %I6 = phi i32 [ %V, %0 ], [ 0, %T ]             ; <i32> [#uses=1]
23*9880d681SAndroid Build Coastguard Worker        call void @use( i1 %B1 )
24*9880d681SAndroid Build Coastguard Worker        call void @use.upgrd.1( i32 %I6 )
25*9880d681SAndroid Build Coastguard Worker        ret void
26*9880d681SAndroid Build Coastguard Worker}
27*9880d681SAndroid Build Coastguard Worker
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