xref: /llvm-project/llvm/test/Transforms/LoopUnroll/AArch64/full-unroll-trip-count-upper-bound.ll (revision ef992b60798b6cd2c50b25351bfc392e319896b7)
1; RUN: opt -passes=loop-unroll -S -mtriple aarch64 -mcpu=cortex-a57 %s | FileCheck %s -check-prefix=UNROLL
2; RUN: opt -passes=loop-unroll -unroll-max-upperbound=0 -S -mtriple aarch64 -mcpu=cortex-a57 %s | FileCheck %s -check-prefix=NOUNROLL
3
4; This IR comes from this C code:
5;
6;   for (int i = 0; i < 4; i++) {
7;     if (src[i] == 1) {
8;       *dst = i;
9;       break;
10;     }
11;   }
12;
13; This test is meant to check that this loop is unrolled into four iterations.
14; Note that the load on the last iteration is dead and thus doesn't appear in
15; the output.
16
17; UNROLL-LABEL: @test
18; UNROLL: load i32, ptr
19; UNROLL: load i32, ptr
20; UNROLL: load i32, ptr
21; UNROLL-NOT: load i32, ptr
22; NOUNROLL-LABEL: @test
23; NOUNROLL: load i32, ptr
24; NOUNROLL-NOT: load i32, ptr
25
26define void @test(ptr %dst, ptr %src) {
27entry:
28  br label %for.body
29
30for.body:                                         ; preds = %entry, %for.body
31  %i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
32  %0 = sext i32 %i to i64
33  %1 = getelementptr inbounds i32, ptr %src, i64 %0
34  %2 = load i32, ptr %1
35  %inc = add nsw i32 %i, 1
36  %cmp1 = icmp slt i32 %inc, 4
37  %cmp3 = icmp eq i32 %2, 1
38  %or.cond = and i1 %cmp3, %cmp1
39  br i1 %or.cond, label %for.body, label %exit
40
41exit:                                          ; preds = %for.body
42  store i32 %i, ptr %dst
43  ret void
44}
45