xref: /llvm-project/llvm/test/CodeGen/BPF/remove_truncate_2.ll (revision c5037db4acd95790a0ca5061c8fa79c5c291607e)
1; RUN: llc < %s -mtriple=bpf -mcpu=v1 -verify-machineinstrs | FileCheck %s
2
3; Source code:
4; struct xdp_md {
5;   unsigned data;
6;   unsigned data_end;
7; };
8;
9; int gbl;
10; int xdp_dummy(struct xdp_md *xdp)
11; {
12;   char addr = *(char *)(long)xdp->data;
13;   if (gbl) {
14;     if (gbl == 1)
15;       return 1;
16;     if (addr == 1)
17;       return 3;
18;   } else if (addr == 0)
19;     return 2;
20;   return 0;
21; }
22
23%struct.xdp_md = type { i32, i32 }
24
25@gbl = common local_unnamed_addr global i32 0, align 4
26
27; Function Attrs: norecurse nounwind readonly
28define i32 @xdp_dummy(ptr nocapture readonly %xdp) local_unnamed_addr #0 {
29entry:
30  %0 = load i32, ptr %xdp, align 4
31  %conv = zext i32 %0 to i64
32  %1 = inttoptr i64 %conv to ptr
33  %2 = load i8, ptr %1, align 1
34; CHECK:  r1 = *(u32 *)(r1 + 0)
35; CHECK:  r1 = *(u8 *)(r1 + 0)
36  %3 = load i32, ptr @gbl, align 4
37  switch i32 %3, label %if.end [
38    i32 0, label %if.else
39    i32 1, label %cleanup
40  ]
41
42if.end:                                           ; preds = %entry
43  %cmp4 = icmp eq i8 %2, 1
44; CHECK:  r0 = 3
45; CHECK-NOT:  r1 &= 255
46; CHECK:  if r1 == 1 goto
47  br i1 %cmp4, label %cleanup, label %if.end13
48
49if.else:                                          ; preds = %entry
50  %cmp9 = icmp eq i8 %2, 0
51; CHECK:  r0 = 2
52; CHECK-NOT:  r1 &= 255
53; CHECK:  if r1 == 0 goto
54  br i1 %cmp9, label %cleanup, label %if.end13
55
56if.end13:                                         ; preds = %if.else, %if.end
57  br label %cleanup
58
59cleanup:                                          ; preds = %if.else, %if.end, %entry, %if.end13
60  %retval.0 = phi i32 [ 0, %if.end13 ], [ 1, %entry ], [ 3, %if.end ], [ 2, %if.else ]
61  ret i32 %retval.0
62}
63
64attributes #0 = { norecurse nounwind readonly }
65