xref: /llvm-project/llvm/test/CodeGen/AArch64/aarch64-gep-opt.ll (revision 78f2eb8d0f9cf5e8a79b64f6d64deeb487502e38)
1; RUN: llc -O3 -aarch64-enable-gep-opt=true -verify-machineinstrs %s -o - | FileCheck %s
2; RUN: llc -O3 -aarch64-enable-gep-opt=true -print-after=codegenprepare < %s 2>&1 | FileCheck --check-prefix=CHECK-UseAA %s
3; RUN: llc -O3 -aarch64-enable-gep-opt=true -aarch64-use-aa=false -print-after=codegenprepare < %s 2>&1 | FileCheck --check-prefix=CHECK-NoAA %s
4; RUN: llc -O3 -aarch64-enable-gep-opt=true -print-after=codegenprepare -mcpu=cyclone < %s 2>&1 | FileCheck --check-prefix=CHECK-UseAA %s
5; RUN: llc -O3 -aarch64-enable-gep-opt=true -print-after=codegenprepare -mcpu=cortex-a53 < %s 2>&1 | FileCheck --check-prefix=CHECK-UseAA %s
6
7target datalayout = "e-m:e-i64:64-i128:128-n32:64-S128"
8target triple = "aarch64"
9
10; Following test cases test enabling SeparateConstOffsetFromGEP pass in AArch64
11; backend. If useAA() returns true, it will lower a GEP with multiple indices
12; into GEPs with a single index, otherwise it will lower it into a
13; "ptrtoint+arithmetics+inttoptr" form.
14
15%struct = type { i32, i32, i32, i32, [20 x i32] }
16
17; Check that when two complex GEPs are used in two basic blocks, LLVM can
18; eliminate the common subexpression for the second use.
19define void @test_GEP_CSE(ptr %string, ptr %adj, i32 %lib, i64 %idxprom) {
20  %liberties = getelementptr [240 x %struct], ptr %string, i64 1, i64 %idxprom, i32 3
21  %1 = load i32, ptr %liberties, align 4
22  %cmp = icmp eq i32 %1, %lib
23  br i1 %cmp, label %if.then, label %if.end
24
25if.then:                                          ; preds = %entry
26  %origin = getelementptr [240 x %struct], ptr %string, i64 1, i64 %idxprom, i32 2
27  %2 = load i32, ptr %origin, align 4
28  store i32 %2, ptr %adj, align 4
29  br label %if.end
30
31if.end:                                           ; preds = %if.then, %entry
32  ret void
33}
34
35; CHECK-LABEL: test_GEP_CSE:
36; CHECK: madd
37; CHECK: ldr
38; CHECK-NOT: madd
39; CHECK:ldr
40
41; CHECK-NoAA-LABEL: @test_GEP_CSE(
42; CHECK-NoAA: [[PTR0:%[a-zA-Z0-9]+]] = ptrtoint ptr %string to i64
43; CHECK-NoAA: [[PTR1:%[a-zA-Z0-9]+]] = mul i64 %idxprom, 96
44; CHECK-NoAA: [[PTR2:%[a-zA-Z0-9]+]] = add i64 [[PTR0]], [[PTR1]]
45; CHECK-NoAA: add i64 [[PTR2]], 23052
46; CHECK-NoAA: inttoptr
47; CHECK-NoAA: if.then:
48; CHECK-NoAA-NOT: ptrtoint
49; CHECK-NoAA-NOT: mul
50; CHECK-NoAA: add i64 [[PTR2]], 23048
51; CHECK-NoAA: inttoptr
52
53; CHECK-UseAA-LABEL: @test_GEP_CSE(
54; CHECK-UseAA: [[IDX:%[a-zA-Z0-9]+]] = mul i64 %idxprom, 96
55; CHECK-UseAA: [[PTR1:%[a-zA-Z0-9]+]] = getelementptr i8, ptr %string, i64 [[IDX]]
56; CHECK-UseAA: getelementptr i8, ptr [[PTR1]], i64 23052
57; CHECK-UseAA: if.then:
58; CHECK-UseAA: getelementptr i8, ptr [[PTR1]], i64 23048
59
60%class.my = type { i32, [128 x i32], i32, [256 x %struct.pt]}
61%struct.pt = type { ptr, i32, i32 }
62%struct.point = type { i32, i32 }
63
64; Check when a GEP is used across two basic block, LLVM can sink the address
65; calculation and code gen can generate a better addressing mode for the second
66; use.
67define void @test_GEP_across_BB(ptr %this, i64 %idx) {
68  %1 = getelementptr %class.my, ptr %this, i64 0, i32 3, i64 %idx, i32 1
69  %2 = load i32, ptr %1, align 4
70  %3 = getelementptr %class.my, ptr %this, i64 0, i32 3, i64 %idx, i32 2
71  %4 = load i32, ptr %3, align 4
72  %5 = icmp eq i32 %2, %4
73  br i1 %5, label %if.true, label %exit
74
75if.true:
76  %6 = shl i32 %4, 1
77  store i32 %6, ptr %3, align 4
78  br label %exit
79
80exit:
81  %7 = add nsw i32 %4, 1
82  store i32 %7, ptr %1, align 4
83  ret void
84}
85; CHECK-LABEL: test_GEP_across_BB:
86; CHECK: ldr {{w[0-9]+}}, [{{x[0-9]+}}, #528]
87; CHECK: ldr {{w[0-9]+}}, [{{x[0-9]+}}, #532]
88; CHECK-NOT: add
89; CHECK: str {{w[0-9]+}}, [{{x[0-9]+}}, #532]
90; CHECK: str {{w[0-9]+}}, [{{x[0-9]+}}, #528]
91
92; CHECK-NoAA-LABEL: test_GEP_across_BB(
93; CHECK-NoAA: add i64 [[TMP:%[a-zA-Z0-9]+]], 528
94; CHECK-NoAA: add i64 [[TMP]], 532
95; CHECK-NoAA: if.true:
96; CHECK-NoAA: inttoptr
97; CHECK-NoAA: {{%sunk[a-zA-Z0-9]+}} = getelementptr i8, {{.*}}, i64 532
98; CHECK-NoAA: exit:
99; CHECK-NoAA: inttoptr
100; CHECK-NoAA: {{%sunk[a-zA-Z0-9]+}} = getelementptr i8, {{.*}}, i64 528
101
102; CHECK-UseAA-LABEL: test_GEP_across_BB(
103; CHECK-UseAA: [[PTR0:%[a-zA-Z0-9]+]] = getelementptr
104; CHECK-UseAA: getelementptr i8, ptr [[PTR0]], i64 528
105; CHECK-UseAA: getelementptr i8, ptr [[PTR0]], i64 532
106; CHECK-UseAA: if.true:
107; CHECK-UseAA: {{%sunk[a-zA-Z0-9]+}} = getelementptr i8, ptr [[PTR0]], i64 532
108; CHECK-UseAA: exit:
109; CHECK-UseAA: {{%sunk[a-zA-Z0-9]+}} = getelementptr i8, ptr [[PTR0]], i64 528
110
111%struct.S = type { float, double }
112@struct_array = global [1024 x %struct.S] zeroinitializer, align 16
113
114; The following two test cases check we can extract constant from indices of
115; struct type.
116; The constant offsets are from indices "i64 %idxprom" and "i32 1". As the
117; alloca size of %struct.S is 16, and "i32 1" is the 2rd element whose field
118; offset is 8, the total constant offset is (5 * 16 + 8) = 88.
119define ptr @test-struct_1(i32 %i) {
120entry:
121  %add = add nsw i32 %i, 5
122  %idxprom = sext i32 %add to i64
123  %p = getelementptr [1024 x %struct.S], ptr @struct_array, i64 0, i64 %idxprom, i32 1
124  ret ptr %p
125}
126; CHECK-NoAA-LABEL: @test-struct_1(
127; CHECK-NoAA-NOT: getelementptr
128; CHECK-NoAA: add i64 %{{[a-zA-Z0-9]+}}, 88
129
130; CHECK-UseAA-LABEL: @test-struct_1(
131; CHECK-UseAA: getelementptr i8, ptr %{{[a-zA-Z0-9]+}}, i64 88
132
133%struct3 = type { i64, i32 }
134%struct2 = type { %struct3, i32 }
135%struct1 = type { i64, %struct2 }
136%struct0 = type { i32, i32, ptr, [100 x %struct1] }
137
138; The constant offsets are from indices "i32 3", "i64 %arrayidx" and "i32 1".
139; "i32 3" is the 4th element whose field offset is 16. The alloca size of
140; %struct1 is 32. "i32 1" is the 2rd element whose field offset is 8. So the
141; total constant offset is 16 + (-2 * 32) + 8 = -40
142define ptr @test-struct_2(ptr %ptr, i64 %idx) {
143entry:
144  %arrayidx = add nsw i64 %idx, -2
145  %ptr2 = getelementptr %struct0, ptr %ptr, i64 0, i32 3, i64 %arrayidx, i32 1
146  ret ptr %ptr2
147}
148; CHECK-NoAA-LABEL: @test-struct_2(
149; CHECK-NoAA-NOT: = getelementptr
150; CHECK-NoAA: add i64 %{{[a-zA-Z0-9]+}}, -40
151
152; CHECK-UseAA-LABEL: @test-struct_2(
153; CHECK-UseAA: getelementptr i8, ptr %{{[a-zA-Z0-9]+}}, i64 -40
154
155; Test that when a index is added from two constant, SeparateConstOffsetFromGEP
156; pass does not generate incorrect result.
157define void @test_const_add(ptr %in) {
158  %inc = add nsw i32 2, 1
159  %idxprom = sext i32 %inc to i64
160  %arrayidx = getelementptr [3 x i32], ptr %in, i64 %idxprom, i64 2
161  store i32 0, ptr %arrayidx, align 4
162  ret void
163}
164; CHECK-LABEL: test_const_add:
165; CHECK: str wzr, [x0, #44]
166