xref: /llvm-project/llvm/test/Transforms/LoopFusion/hoist_load.ll (revision 055fb7795aa219a3d274d280ec9129784f169f56)
1; RUN: opt -S -passes=loop-simplify,loop-fusion -debug-only=loop-fusion < %s 2>&1 | FileCheck %s
2; REQUIRES: asserts
3; CHECK: Safe to hoist.
4
5@A = common global [100 x i32] zeroinitializer, align 16
6define void @hoist_preheader(i32 %N) {
7; CHECK-LABEL: @hoist_preheader(
8; CHECK-NEXT:  pre1:
9; CHECK-NEXT:    [[PTR:%.*]] = alloca i32, align 4
10; CHECK-NEXT:    [[B:%.*]] = load i32, ptr [[PTR]], align 4
11; CHECK-NEXT:    br label [[BODY1:%.*]]
12; CHECK:       body1:
13; CHECK-NEXT:    [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[BODY1]] ], [ 0, [[PRE1:%.*]] ]
14; CHECK-NEXT:    [[I2:%.*]] = phi i32 [ [[I_NEXT2:%.*]], [[BODY1]] ], [ 0, [[PRE1]] ]
15; CHECK-NEXT:    [[I_NEXT]] = add i32 1, [[I]]
16; CHECK-NEXT:    [[COND:%.*]] = icmp ne i32 [[I]], [[N:%.*]]
17; CHECK-NEXT:    [[I_NEXT2]] = add i32 1, [[I2]]
18; CHECK-NEXT:    [[COND2:%.*]] = icmp ne i32 [[I2]], [[N]]
19; CHECK-NEXT:    br i1 [[COND2]], label [[BODY1]], label [[EXIT:%.*]]
20; CHECK:       exit:
21; CHECK-NEXT:    ret void
22;
23pre1:
24  %ptr = alloca i32
25  br label %body1
26
27body1:  ; preds = %pre1, %body1
28  %i = phi i32 [%i_next, %body1], [0, %pre1]
29  %i_next = add i32 1, %i
30  %cond = icmp ne i32 %i, %N
31  br i1 %cond, label %body1, label %pre2
32
33pre2:
34  %b = load i32, ptr %ptr
35  br label %body2
36
37body2:  ; preds = %pre2, %body2
38  %i2 = phi i32 [%i_next2, %body2], [0, %pre2]
39  %i_next2 = add i32 1, %i2
40  %cond2 = icmp ne i32 %i2, %N
41  br i1 %cond2, label %body2, label %exit
42
43exit:
44  ret void
45}
46