xref: /aosp_15_r20/external/llvm/test/Transforms/LoopDeletion/dcetest.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)
1*9880d681SAndroid Build Coastguard Worker; This is the test case taken from Appel's book that illustrates a hard case
2*9880d681SAndroid Build Coastguard Worker; that SCCP gets right, and when followed by ADCE, is completely eliminated
3*9880d681SAndroid Build Coastguard Worker;
4*9880d681SAndroid Build Coastguard Worker; RUN: opt < %s -sccp -simplifycfg -indvars -loop-deletion -dce -simplifycfg -S | not grep br
5*9880d681SAndroid Build Coastguard Worker
6*9880d681SAndroid Build Coastguard Workerdefine i32 @"test function"(i32 %i0, i32 %j0) {
7*9880d681SAndroid Build Coastguard WorkerBB1:
8*9880d681SAndroid Build Coastguard Worker        br label %BB2
9*9880d681SAndroid Build Coastguard Worker
10*9880d681SAndroid Build Coastguard WorkerBB2:            ; preds = %BB7, %BB1
11*9880d681SAndroid Build Coastguard Worker        %j2 = phi i32 [ %j4, %BB7 ], [ 1, %BB1 ]                ; <i32> [#uses=2]
12*9880d681SAndroid Build Coastguard Worker        %k2 = phi i32 [ %k4, %BB7 ], [ 0, %BB1 ]                ; <i32> [#uses=4]
13*9880d681SAndroid Build Coastguard Worker        %kcond = icmp slt i32 %k2, 100          ; <i1> [#uses=1]
14*9880d681SAndroid Build Coastguard Worker        br i1 %kcond, label %BB3, label %BB4
15*9880d681SAndroid Build Coastguard Worker
16*9880d681SAndroid Build Coastguard WorkerBB3:            ; preds = %BB2
17*9880d681SAndroid Build Coastguard Worker        %jcond = icmp slt i32 %j2, 20           ; <i1> [#uses=1]
18*9880d681SAndroid Build Coastguard Worker        br i1 %jcond, label %BB5, label %BB6
19*9880d681SAndroid Build Coastguard Worker
20*9880d681SAndroid Build Coastguard WorkerBB4:            ; preds = %BB2
21*9880d681SAndroid Build Coastguard Worker        ret i32 %j2
22*9880d681SAndroid Build Coastguard Worker
23*9880d681SAndroid Build Coastguard WorkerBB5:            ; preds = %BB3
24*9880d681SAndroid Build Coastguard Worker        %k3 = add i32 %k2, 1            ; <i32> [#uses=1]
25*9880d681SAndroid Build Coastguard Worker        br label %BB7
26*9880d681SAndroid Build Coastguard Worker
27*9880d681SAndroid Build Coastguard WorkerBB6:            ; preds = %BB3
28*9880d681SAndroid Build Coastguard Worker        %k5 = add i32 %k2, 1            ; <i32> [#uses=1]
29*9880d681SAndroid Build Coastguard Worker        br label %BB7
30*9880d681SAndroid Build Coastguard Worker
31*9880d681SAndroid Build Coastguard WorkerBB7:            ; preds = %BB6, %BB5
32*9880d681SAndroid Build Coastguard Worker        %j4 = phi i32 [ 1, %BB5 ], [ %k2, %BB6 ]                ; <i32> [#uses=1]
33*9880d681SAndroid Build Coastguard Worker        %k4 = phi i32 [ %k3, %BB5 ], [ %k5, %BB6 ]              ; <i32> [#uses=1]
34*9880d681SAndroid Build Coastguard Worker        br label %BB2
35*9880d681SAndroid Build Coastguard Worker}
36*9880d681SAndroid Build Coastguard Worker
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