xref: /llvm-project/llvm/test/CodeGen/Thumb/branch-to-return.ll (revision b31fffbc7f1e0491bf599e82b7195e320d26e140)
1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
2; RUN: llc -mtriple=thumbv7 %s -o - | FileCheck %s
3
4; Test the branch to return in BB4 is converted to return.
5
6define i32 @foo(ptr %x, i32 %n) {
7; CHECK-LABEL: foo:
8; CHECK:       @ %bb.0: @ %entry
9; CHECK-NEXT:    cmp r1, #1
10; CHECK-NEXT:    blt .LBB0_4
11; CHECK-NEXT:  @ %bb.1: @ %for.body.preheader
12; CHECK-NEXT:    bic r3, r1, #3
13; CHECK-NEXT:    mov r12, r0
14; CHECK-NEXT:    cmp r1, #4
15; CHECK-NEXT:    bhs .LBB0_3
16; CHECK-NEXT:  @ %bb.2:
17; CHECK-NEXT:    movs r0, #0
18; CHECK-NEXT:    b .LBB0_6
19; CHECK-NEXT:  .LBB0_3: @ %middle.block
20; CHECK-NEXT:    cmp r1, r3
21; CHECK-NEXT:    bne .LBB0_5
22; CHECK-NEXT:  .LBB0_4:
23; CHECK-NEXT:    movs r0, #0
24; CHECK-NEXT:    bx lr
25; CHECK-NEXT:  .LBB0_5:
26; CHECK-NEXT:    ldr.w r0, [r12]
27; CHECK-NEXT:  .LBB0_6: @ %for.body.preheader1
28; CHECK-NEXT:    subs r3, r1, r3
29; CHECK-NEXT:    mvn r2, #12
30; CHECK-NEXT:    and.w r1, r2, r1, lsl #2
31; CHECK-NEXT:    add r1, r12
32; CHECK-NEXT:  .LBB0_7: @ %for.body
33; CHECK-NEXT:    @ =>This Inner Loop Header: Depth=1
34; CHECK-NEXT:    ldr r2, [r1], #4
35; CHECK-NEXT:    subs r3, #1
36; CHECK-NEXT:    add r0, r2
37; CHECK-NEXT:    bne .LBB0_7
38; CHECK-NEXT:  @ %bb.8: @ %for.cond.cleanup
39; CHECK-NEXT:    bx lr
40entry:
41  %n.vec = and i32 %n, -4
42  %cmp6 = icmp sgt i32 %n, 0
43  br i1 %cmp6, label %for.body.preheader, label %for.cond.cleanup
44
45for.body.preheader:                               ; preds = %entry
46  %min.iters.check = icmp ult i32 %n, 4
47  br i1 %min.iters.check, label %for.body.preheader1, label %middle.block
48
49middle.block:
50  %x3 = load i32, ptr %x, align 4
51  %cmp.n = icmp eq i32 %n.vec, %n
52  br i1 %cmp.n, label %for.cond.cleanup, label %for.body.preheader1
53
54for.body.preheader1:                              ; preds = %middle.block, %for.body.preheader
55  %r.07.ph = phi i32 [ 0, %for.body.preheader ], [ %x3, %middle.block ]
56  br label %for.body
57
58for.body:                                         ; preds = %for.body.preheader1, %for.body
59  %i.08 = phi i32 [ %inc, %for.body ], [ %n.vec, %for.body.preheader1 ]
60  %r.07 = phi i32 [ %add, %for.body ], [ %r.07.ph, %for.body.preheader1 ]
61  %arrayidx = getelementptr inbounds i32, ptr %x, i32 %i.08
62  %v5 = load i32, ptr %arrayidx, align 4
63  %add = add nsw i32 %v5, %r.07
64  %inc = add nuw nsw i32 %i.08, 1
65  %exitcond = icmp eq i32 %inc, %n
66  br i1 %exitcond, label %for.cond.cleanup, label %for.body
67
68for.cond.cleanup:                                 ; preds = %for.body, %middle.block, %entry
69  %r.0.lcssa = phi i32 [ 0, %entry ], [ 0, %middle.block ], [ %add, %for.body ]
70  ret i32 %r.0.lcssa
71}
72