xref: /llvm-project/llvm/test/Analysis/MemoryDependenceAnalysis/InvariantLoad.ll (revision 4e49c9da14f75f47ca5cb0b4290d9c1c30d3d060) 
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=gvn -S | FileCheck %s
3
4target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128-ni:1"
5target triple = "x86_64-unknown-linux-gnu"
6
7declare void @llvm.memset.p0.i8(ptr, i8, i32, i1)
8declare void @foo(ptr)
9
10define i8 @test(i1 %cmp) {
11; CHECK-LABEL: @test(
12; CHECK-NEXT:  entry:
13; CHECK-NEXT:    [[P:%.*]] = alloca i8
14; CHECK-NEXT:    store i8 5, ptr [[P]]
15; CHECK-NEXT:    br label [[HEADER:%.*]]
16; CHECK:       header:
17; CHECK-NEXT:    [[V:%.*]] = phi i8 [ 5, [[ENTRY:%.*]] ], [ -5, [[ALIVE:%.*]] ]
18; CHECK-NEXT:    [[I:%.*]] = phi i8 [ 0, [[ENTRY]] ], [ [[I_INC:%.*]], [[ALIVE]] ]
19; CHECK-NEXT:    br i1 [[CMP:%.*]], label [[ALIVE]], label [[DEAD:%.*]]
20; CHECK:       dead:
21; CHECK-NEXT:    call void @foo(ptr [[P]])
22; CHECK-NEXT:    [[I_1:%.*]] = add i8 [[I]], [[V]]
23; CHECK-NEXT:    br label [[ALIVE]]
24; CHECK:       alive:
25; CHECK-NEXT:    [[I_2:%.*]] = phi i8 [ [[I]], [[HEADER]] ], [ [[I_1]], [[DEAD]] ]
26; CHECK-NEXT:    store i8 -5, ptr [[P]]
27; CHECK-NEXT:    call void @llvm.memset.p0.i32(ptr align 1 [[P]], i8 0, i32 1, i1 false)
28; CHECK-NEXT:    [[I_INC]] = add i8 [[I_2]], 1
29; CHECK-NEXT:    [[CMP_LOOP:%.*]] = icmp ugt i8 [[I_INC]], 100
30; CHECK-NEXT:    br i1 [[CMP_LOOP]], label [[EXIT:%.*]], label [[HEADER]]
31; CHECK:       exit:
32; CHECK-NEXT:    ret i8 0
33;
34
35entry:
36  %p = alloca i8
37  store i8 5, ptr %p
38  br label %header
39header:
40  %i = phi i8 [0, %entry], [%i.inc, %backedge]
41  br i1 %cmp, label %alive, label %dead
42dead:
43  call void @foo(ptr %p)
44  %v = load i8, ptr %p, !invariant.load !1
45  %i.1 = add i8 %i, %v
46  br label %alive
47alive:
48  %i.2 = phi i8 [%i, %header], [%i.1, %dead]
49  store i8 -5, ptr %p
50  br label %backedge
51backedge:
52  call void @llvm.memset.p0.i8(ptr align 1 %p, i8 0, i32 1, i1 false)
53  %i.inc = add i8 %i.2, 1
54  %cmp.loop = icmp ugt i8 %i.inc, 100
55  br i1 %cmp.loop, label %exit, label %header
56exit:
57  %res = load i8, ptr %p
58  ret i8 %res
59}
60
61; Check that first two loads are not optimized out while the one marked with
62; invariant.load reuses %res1
63define i8 @test2(i1 %cmp, ptr %p) {
64; CHECK-LABEL: @test2(
65; CHECK-NEXT:  entry:
66; CHECK-NEXT:    [[RES1:%.*]] = load i8, ptr [[P:%.*]], align 1
67; CHECK-NEXT:    call void @foo(ptr [[P]])
68; CHECK-NEXT:    br i1 [[CMP:%.*]], label [[B2:%.*]], label [[B1:%.*]]
69; CHECK:       b1:
70; CHECK-NEXT:    [[RES2:%.*]] = load i8, ptr [[P]]
71; CHECK-NEXT:    [[RES3:%.*]] = add i8 [[RES1]], [[RES2]]
72; CHECK-NEXT:    br label [[ALIVE:%.*]]
73; CHECK:       b2:
74; CHECK-NEXT:    [[RES_DEAD:%.*]] = add i8 [[RES1]], [[RES1]]
75; CHECK-NEXT:    br label [[ALIVE]]
76; CHECK:       alive:
77; CHECK-NEXT:    [[RES_PHI:%.*]] = phi i8 [ [[RES3]], [[B1]] ], [ [[RES_DEAD]], [[B2]] ]
78; CHECK-NEXT:    ret i8 [[RES_PHI]]
79;
80
81entry:
82  %res1 = load i8, ptr %p
83  call void @foo(ptr %p)
84  br i1 %cmp, label %b2, label %b1
85b1:
86  %res2 = load i8, ptr %p
87  %res3 = add i8 %res1, %res2
88  br label %alive
89b2:
90  %v = load i8, ptr %p, !invariant.load !1
91  %res.dead = add i8 %v, %res1
92  br label %alive
93alive:
94  %res.phi = phi i8 [%res3, %b1], [%res.dead, %b2]
95  ret i8 %res.phi
96}
97
98; This is essentially the same test case as the above one but with %b1 and %b2
99; swapped in "br i1 %cmp, label %b1, label %b2" instruction. That helps us to
100; ensure that results doesn't depend on visiting order.
101define i8 @test3(i1 %cmp, ptr %p) {
102; CHECK-LABEL: @test3(
103; CHECK-NEXT:  entry:
104; CHECK-NEXT:    [[RES1:%.*]] = load i8, ptr [[P:%.*]], align 1
105; CHECK-NEXT:    call void @foo(ptr [[P]])
106; CHECK-NEXT:    br i1 [[CMP:%.*]], label [[B1:%.*]], label [[B2:%.*]]
107; CHECK:       b1:
108; CHECK-NEXT:    [[RES2:%.*]] = load i8, ptr [[P]]
109; CHECK-NEXT:    [[RES3:%.*]] = add i8 [[RES1]], [[RES2]]
110; CHECK-NEXT:    br label [[ALIVE:%.*]]
111; CHECK:       b2:
112; CHECK-NEXT:    [[RES_DEAD:%.*]] = add i8 [[RES1]], [[RES1]]
113; CHECK-NEXT:    br label [[ALIVE]]
114; CHECK:       alive:
115; CHECK-NEXT:    [[RES_PHI:%.*]] = phi i8 [ [[RES3]], [[B1]] ], [ [[RES_DEAD]], [[B2]] ]
116; CHECK-NEXT:    ret i8 [[RES_PHI]]
117;
118entry:
119  %res1 = load i8, ptr %p
120  call void @foo(ptr %p)
121  br i1 %cmp, label %b1, label %b2
122b1:
123  %res2 = load i8, ptr %p
124  %res3 = add i8 %res1, %res2
125  br label %alive
126b2:
127  %v = load i8, ptr %p, !invariant.load !1
128  %res.dead = add i8 %v, %res1
129  br label %alive
130alive:
131  %res.phi = phi i8 [%res3, %b1], [%res.dead, %b2]
132  ret i8 %res.phi
133}
134
135
136; This is reduced test case catching regression in the first version of the
137; fix for invariant loads (https://reviews.llvm.org/D64405).
138define void @test4() {
139; CHECK-LABEL: @test4(
140; CHECK-NEXT:  entry:
141; CHECK-NEXT:    [[TMP0:%.*]] = load float, ptr inttoptr (i64 8 to ptr), align 4
142; CHECK-NEXT:    [[TMP1:%.*]] = fmul float [[TMP0]], [[TMP0]]
143; CHECK-NEXT:    br label [[FUSION_LOOP_HEADER_DIM_1_PREHEADER:%.*]]
144; CHECK:       fusion.loop_header.dim.1.preheader:
145; CHECK-NEXT:    [[TMP2:%.*]] = phi float [ [[TMP0]], [[ENTRY:%.*]] ], [ [[DOTPRE:%.*]], [[FUSION_LOOP_HEADER_DIM_1_PREHEADER]] ]
146; CHECK-NEXT:    [[FUSION_INVAR_ADDRESS_DIM_0_03:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[INVAR_INC3:%.*]], [[FUSION_LOOP_HEADER_DIM_1_PREHEADER]] ]
147; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr inbounds [2 x [1 x [4 x float]]], ptr null, i64 0, i64 [[FUSION_INVAR_ADDRESS_DIM_0_03]], i64 0, i64 2
148; CHECK-NEXT:    [[TMP4:%.*]] = fmul float [[TMP2]], [[TMP2]]
149; CHECK-NEXT:    [[INVAR_INC3]] = add nuw nsw i64 [[FUSION_INVAR_ADDRESS_DIM_0_03]], 1
150; CHECK-NEXT:    [[DOTPHI_TRANS_INSERT:%.*]] = getelementptr inbounds [2 x [1 x [4 x float]]], ptr null, i64 0, i64 [[INVAR_INC3]], i64 0, i64 2
151; CHECK-NEXT:    [[DOTPRE]] = load float, ptr [[DOTPHI_TRANS_INSERT]], align 4, !invariant.load !0
152; CHECK-NEXT:    br label [[FUSION_LOOP_HEADER_DIM_1_PREHEADER]]
153;
154entry:
155  %0 = getelementptr inbounds [2 x [1 x [4 x float]]], ptr null, i64 0, i64 0, i64 0, i64 2
156  %1 = load float, ptr %0, align 4
157  %2 = fmul float %1, %1
158  br label %fusion.loop_header.dim.1.preheader
159
160fusion.loop_header.dim.1.preheader:               ; preds = %fusion.loop_header.dim.1.preheader, %entry
161  %fusion.invar_address.dim.0.03 = phi i64 [ 0, %entry ], [ %invar.inc3, %fusion.loop_header.dim.1.preheader ]
162  %3 = getelementptr inbounds [2 x [1 x [4 x float]]], ptr null, i64 0, i64 %fusion.invar_address.dim.0.03, i64 0, i64 2
163  %4 = load float, ptr %3, align 4, !invariant.load !1
164  %5 = fmul float %4, %4
165  %6 = getelementptr inbounds [2 x [1 x [4 x float]]], ptr null, i64 0, i64 %fusion.invar_address.dim.0.03, i64 0, i64 2
166  %7 = load float, ptr %6, align 4, !invariant.load !1
167  %8 = fmul float %7, %7
168  %invar.inc3 = add nuw nsw i64 %fusion.invar_address.dim.0.03, 1
169  br label %fusion.loop_header.dim.1.preheader
170}
171
172!1 = !{}
173