xref: /llvm-project/llvm/test/CodeGen/Thumb2/ifcvt-rescan-diamonds.ll (revision b5b663aac17415625340eb29c8010832bfc4c21c)
1; RUN: llc -O2 -arm-atomic-cfg-tidy=0 -o - %s | FileCheck %s
2target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
3target triple = "thumbv8-unknown-linux-gnueabihf"
4
5; This is a tricky test case.
6; The point of it is to create a diamond where both the true block and the
7; false block clobber the predicate when viewed as a whole, but only one of them
8; clobbers the predicate when considering the instructions they share.
9
10; Function Attrs: nounwind
11define void @BN_kronecker(i1 %a, i32 %b) #0 {
12entry:
13  br label %while.cond38
14
15while.cond38:                                     ; preds = %if.end111, %entry
16  %cmp79 = icmp eq i32 0, 0
17  br i1 %a, label %cond.true77, label %cond.false87
18
19; CHECK: %cond.true77
20; CHECK-NEXT: @ in Loop
21; CHECK-NEXT: cmp.w {{r[0-9]+}}, #0
22; CHECK-NEXT: ite eq
23; CHECK-NEXT: ldreq
24  ; N.b. 16-bit mov instruction in IT block does not set flags.
25; CHECK-NEXT: movne
26; CHECK-NEXT: mvns
27; CHECK-NEXT: b
28cond.true77:                                      ; preds = %while.cond38
29  br i1 %cmp79, label %cond.end84, label %cond.false81
30
31cond.false81:                                     ; preds = %cond.true77
32  %0 = load i32, ptr null, align 4
33  br label %cond.end84
34
35cond.end84:                                       ; preds = %cond.false81, %cond.true77
36  %cond85 = phi i32 [ %0, %cond.false81 ], [ 0, %cond.true77 ]
37  %neg86 = xor i32 %cond85, -1
38  br label %cond.false101
39
40cond.false87:                                     ; preds = %while.cond38
41  br i1 %cmp79, label %cond.false101, label %cond.false91
42
43cond.false91:                                     ; preds = %cond.false87
44  br label %cond.false101
45
46cond.false101:                                    ; preds = %cond.false91, %cond.false87, %cond.end84
47  %cond97 = phi i32 [ %neg86, %cond.end84 ], [ %b, %cond.false91 ], [ 0, %cond.false87 ]
48  %1 = load i32, ptr null, align 4
49  %and106 = and i32 %cond97, %1
50  %and107 = and i32 %and106, 2
51  %tobool108 = icmp ne i32 %and107, 0
52  br i1 %tobool108, label %if.then109, label %if.end111
53
54if.then109:                                       ; preds = %cond.false101
55  store i32 0, ptr undef, align 4
56  br label %if.end111
57
58if.end111:                                        ; preds = %if.then109, %cond.false101
59  %tobool113 = icmp ne i32 0, 0
60  br i1 %tobool113, label %while.cond38, label %end
61
62end:                                              ; preds = %if.end111
63  ret void
64}
65
66attributes #0 = { nounwind }
67