xref: /llvm-project/llvm/test/Analysis/ScalarEvolution/2012-05-29-MulAddRec.ll (revision b9808e5660f5fe9e7414c0c0b93acd899235471c)
1; RUN: opt < %s -S -passes='loop(indvars),loop-unroll' | FileCheck %s
2;
3; loop-unroll fully unrolls the inner loop, creating an interesting
4; chain of multiplication. indvars forces SCEV to run again on the
5; outer loop. While reducing the recurrence at %mul3, unsigned integer overflow
6; causes one of the terms to reach zero. This forces all multiples in
7; the recurrence to be zero, reducing the whole thing to a constant expression.
8;
9; PR12929: cast<Ty>() argument of incompatible type
10
11target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
12
13declare void @use(i8 %x)
14
15; CHECK: @func
16; CHECK: for.cond:
17; CHECK: %inc1 = phi i8 [ 0, %entry ], [ %0, %for.body ]
18; CHECK: br label %for.body
19
20; CHECK: for.body:
21; CHECK: %inc.9 = add i8 %inc1, 10
22; CHECK: %0 = add i8 %inc1, 10
23; CHECK: br label %for.cond
24
25define void @func() noreturn nounwind uwtable ssp {
26entry:
27  br label %for.cond
28
29for.cond.loopexit:                                ; preds = %for.body
30  %mul.lcssa = phi i8 [ %mul, %for.body ]
31  %0 = add i8 %inc1, 10
32  %indvars.iv.next = add i8 %indvars.iv, 10
33  br label %for.cond
34
35for.cond:                                         ; preds = %for.cond.loopexit, %entry
36  %indvars.iv = phi i8 [ %indvars.iv.next, %for.cond.loopexit ], [ 10, %entry ]
37  %mul3 = phi i8 [ undef, %entry ], [ %mul.lcssa, %for.cond.loopexit ]
38  %inc1 = phi i8 [ 0, %entry ], [ %0, %for.cond.loopexit ]
39  call void @use(i8 %inc1)
40  br label %for.body
41
42for.body:                                         ; preds = %for.body, %for.cond
43  %inc26 = phi i8 [ %inc1, %for.cond ], [ %inc, %for.body ]
44  %mul45 = phi i8 [ %mul3, %for.cond ], [ %mul, %for.body ]
45  %inc = add i8 %inc26, 1
46  %mul = mul i8 %inc26, %mul45
47  call void @use(i8 %inc)
48  %exitcond = icmp ne i8 %inc, %indvars.iv
49  br i1 %exitcond, label %for.body, label %for.cond.loopexit
50}
51