xref: /llvm-project/llvm/test/Transforms/LoopStrengthReduce/lsr-rewrite-to-add-one.ll (revision 7019624ee124c0560567923ecd808c2d36c40f14)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -passes=loop-reduce -S %s | FileCheck %s
3
4target datalayout = "e-p:64:64-p1:64:64-p2:32:32-p3:32:32-p4:64:64-p5:32:32-p6:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64-S32-A5-G1-ni:7"
5
6define i32 @test(i1 %c.1, ptr %src) {
7; CHECK-LABEL: @test(
8; CHECK-NEXT:  entry:
9; CHECK-NEXT:    br label [[LOOP_HEADER:%.*]]
10; CHECK:       loop.header:
11; CHECK-NEXT:    [[LSR_IV:%.*]] = phi i32 [ [[LSR_IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ], [ 0, [[ENTRY:%.*]] ]
12; CHECK-NEXT:    br i1 [[C_1:%.*]], label [[LOOP_LATCH]], label [[LOOP_THEN:%.*]]
13; CHECK:       loop.then:
14; CHECK-NEXT:    [[L:%.*]] = load i32, ptr [[SRC:%.*]], align 4
15; CHECK-NEXT:    [[C_2:%.*]] = icmp eq i32 [[L]], 0
16; CHECK-NEXT:    br label [[LOOP_LATCH]]
17; CHECK:       loop.latch:
18; CHECK-NEXT:    [[P:%.*]] = phi i1 [ [[C_2]], [[LOOP_THEN]] ], [ false, [[LOOP_HEADER]] ]
19; CHECK-NEXT:    [[T:%.*]] = icmp sgt i32 [[LSR_IV]], -1050
20; CHECK-NEXT:    [[OR:%.*]] = or i1 [[P]], [[T]]
21; CHECK-NEXT:    [[ZEXT_OR:%.*]] = zext i1 [[OR]] to i32
22; CHECK-NEXT:    [[LSR_IV_NEXT]] = add nuw i32 [[LSR_IV]], 1
23; CHECK-NEXT:    [[TMP0:%.*]] = add i32 [[LSR_IV_NEXT]], -1
24; CHECK-NEXT:    [[LOOP_HEADER_TERMCOND:%.*]] = icmp sgt i32 [[TMP0]], -1050
25; CHECK-NEXT:    br i1 [[LOOP_HEADER_TERMCOND]], label [[LOOP_HEADER]], label [[EXIT:%.*]]
26; CHECK:       exit:
27; CHECK-NEXT:    [[ZEXT_OR_LCSSA:%.*]] = phi i32 [ [[ZEXT_OR]], [[LOOP_LATCH]] ]
28; CHECK-NEXT:    ret i32 [[ZEXT_OR_LCSSA]]
29;
30entry:
31  br label %loop.header
32
33loop.header:
34  %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ]
35  br i1 %c.1, label %loop.latch, label %loop.then
36
37loop.then:
38  %l = load i32, ptr %src
39  %c.2 = icmp eq i32 %l, 0
40  br label %loop.latch
41
42loop.latch:
43  %p = phi i1 [ %c.2, %loop.then ], [ 0, %loop.header ]
44  %t = icmp sgt i32 %iv, -1050
45  %or = or i1 %p, %t
46  %zext.or = zext i1 %or to i32
47  %iv.next = add i32 %iv, %zext.or
48  br i1 %t, label %loop.header, label %exit
49
50exit:
51  ret i32 %zext.or
52}
53