xref: /llvm-project/llvm/test/CodeGen/AArch64/func-argpassing.ll (revision 5ddce70ef0e5a641d7fea95e31fc5e2439cb98cb)
1; RUN: llc -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu -disable-post-ra | FileCheck %s
2; RUN: llc -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu -mattr=-fp-armv8 -disable-post-ra | FileCheck --check-prefix=CHECK-NOFP %s
3
4%myStruct = type { i64 , i8, i32 }
5
6@var8 = dso_local global i8 0
7@var32 = dso_local global i32 0
8@var64 = dso_local global i64 0
9@var128 = dso_local global i128 0
10@varfloat = dso_local global float 0.0
11@vardouble = dso_local global double 0.0
12@varstruct = dso_local global %myStruct zeroinitializer
13
14define dso_local void @take_i8s(i8 %val1, i8 %val2) {
15; CHECK-LABEL: take_i8s:
16    store i8 %val2, ptr @var8
17    ; Not using w1 may be technically allowed, but it would indicate a
18    ; problem in itself.
19;  CHECK: strb w1, [{{x[0-9]+}}, {{#?}}:lo12:var8]
20    ret void
21}
22
23define dso_local void @add_floats(float %val1, float %val2) {
24; CHECK-LABEL: add_floats:
25    %newval = fadd float %val1, %val2
26; CHECK: fadd [[ADDRES:s[0-9]+]], s0, s1
27; CHECK-NOFP-NOT: fadd
28    store float %newval, ptr @varfloat
29; CHECK: str [[ADDRES]], [{{x[0-9]+}}, {{#?}}:lo12:varfloat]
30    ret void
31}
32
33; byval pointers should be allocated to the stack and copied as if
34; with memcpy.
35define dso_local void @take_struct(ptr byval(%myStruct) %structval) {
36; CHECK-LABEL: take_struct:
37    %addr0 = getelementptr %myStruct, ptr %structval, i64 0, i32 2
38
39    %val0 = load volatile i32, ptr %addr0
40    ; Some weird move means x0 is used for one access
41; CHECK: ldr [[REG32:w[0-9]+]], [{{x[0-9]+|sp}}, #12]
42    store volatile i32 %val0, ptr @var32
43; CHECK: str [[REG32]], [{{x[0-9]+}}, {{#?}}:lo12:var32]
44
45    %val1 = load volatile i64, ptr %structval
46; CHECK: ldr [[REG64:x[0-9]+]], [{{x[0-9]+|sp}}]
47    store volatile i64 %val1, ptr @var64
48; CHECK: str [[REG64]], [{{x[0-9]+}}, {{#?}}:lo12:var64]
49
50    ret void
51}
52
53; %structval should be at sp + 16
54define dso_local void @check_byval_align(ptr byval(i32) %ignore, ptr byval(%myStruct) align 16 %structval) {
55; CHECK-LABEL: check_byval_align:
56
57    %addr0 = getelementptr %myStruct, ptr %structval, i64 0, i32 2
58
59    %val0 = load volatile i32, ptr %addr0
60    ; Some weird move means x0 is used for one access
61; CHECK: ldr [[REG32:w[0-9]+]], [sp, #28]
62    store i32 %val0, ptr @var32
63; CHECK: str [[REG32]], [{{x[0-9]+}}, {{#?}}:lo12:var32]
64
65    %val1 = load volatile i64, ptr %structval
66; CHECK: ldr [[REG64:x[0-9]+]], [sp, #16]
67    store i64 %val1, ptr @var64
68; CHECK: str [[REG64]], [{{x[0-9]+}}, {{#?}}:lo12:var64]
69
70    ret void
71}
72
73define dso_local i32 @return_int() {
74; CHECK-LABEL: return_int:
75    %val = load i32, ptr @var32
76    ret i32 %val
77; CHECK: ldr w0, [{{x[0-9]+}}, {{#?}}:lo12:var32]
78    ; Make sure epilogue follows
79; CHECK-NEXT: ret
80}
81
82define dso_local double @return_double() {
83; CHECK-LABEL: return_double:
84    ret double 3.14
85; CHECK: ldr d0, [{{x[0-9]+}}, {{#?}}:lo12:.LCPI
86; CHECK-NOFP-NOT: ldr d0,
87}
88
89; This is the kind of IR clang will produce for returning a struct
90; small enough to go into registers. Not all that pretty, but it
91; works.
92define [2 x i64] @return_struct() {
93; CHECK-LABEL: return_struct:
94    %val = load [2 x i64], ptr @varstruct
95    ret [2 x i64] %val
96; CHECK: add x[[VARSTRUCT:[0-9]+]], {{x[0-9]+}}, :lo12:varstruct
97; CHECK: ldp x0, x1, [x[[VARSTRUCT]]]
98    ; Make sure epilogue immediately follows
99; CHECK-NEXT: ret
100}
101
102; Large structs are passed by reference (storage allocated by caller
103; to preserve value semantics) in x8. Strictly this only applies to
104; structs larger than 16 bytes, but C semantics can still be provided
105; if LLVM does it to %myStruct too. So this is the simplest check
106define dso_local void @return_large_struct(ptr sret(%myStruct) %retval) {
107; CHECK-LABEL: return_large_struct:
108    %addr1 = getelementptr %myStruct, ptr %retval, i64 0, i32 1
109    %addr2 = getelementptr %myStruct, ptr %retval, i64 0, i32 2
110
111    store i64 42, ptr %retval
112    store i8 2, ptr %addr1
113    store i32 9, ptr %addr2
114; CHECK: str {{x[0-9]+}}, [x8]
115; CHECK: strb {{w[0-9]+}}, [x8, #8]
116; CHECK: str {{w[0-9]+}}, [x8, #12]
117
118    ret void
119}
120
121; This struct is just too far along to go into registers: (only x7 is
122; available, but it needs two). Also make sure that %stacked doesn't
123; sneak into x7 behind.
124define dso_local i32 @struct_on_stack(i8 %var0, i16 %var1, i32 %var2, i64 %var3, i128 %var45,
125                          ptr %var6, ptr byval(%myStruct) %struct, ptr byval(i32) %stacked,
126                          double %notstacked) {
127; CHECK-LABEL: struct_on_stack:
128    %val64 = load volatile i64, ptr %struct
129    store volatile i64 %val64, ptr @var64
130    ; Currently nothing on local stack, so struct should be at sp
131; CHECK: ldr [[VAL64:x[0-9]+]], [sp]
132; CHECK: str [[VAL64]], [{{x[0-9]+}}, {{#?}}:lo12:var64]
133
134    store volatile double %notstacked, ptr @vardouble
135; CHECK-NOT: ldr d0
136; CHECK: str d0, [{{x[0-9]+}}, {{#?}}:lo12:vardouble
137; CHECK-NOFP-NOT: str d0,
138
139    %retval = load volatile i32, ptr %stacked
140    ret i32 %retval
141; CHECK-LE: ldr w0, [sp, #16]
142}
143
144define dso_local void @stacked_fpu(float %var0, double %var1, float %var2, float %var3,
145                         float %var4, float %var5, float %var6, float %var7,
146                         float %var8) {
147; CHECK-LABEL: stacked_fpu:
148    store float %var8, ptr @varfloat
149    ; Beware as above: the offset would be different on big-endian
150    ; machines if the first ldr were changed to use s-registers.
151; CHECK: ldr {{[ds]}}[[VALFLOAT:[0-9]+]], [sp]
152; CHECK: str s[[VALFLOAT]], [{{x[0-9]+}}, {{#?}}:lo12:varfloat]
153
154    ret void
155}
156
157; 128-bit integer types should be passed in xEVEN, xODD rather than
158; the reverse. In this case x2 and x3. Nothing should use x1.
159define dso_local i64 @check_i128_regalign(i32 %val0, i128 %val1, i64 %val2) {
160; CHECK-LABEL: check_i128_regalign
161    store i128 %val1, ptr @var128
162; CHECK-DAG: add x[[VAR128:[0-9]+]], {{x[0-9]+}}, :lo12:var128
163; CHECK-DAG: stp x2, x3, [x[[VAR128]]]
164
165    ret i64 %val2
166; CHECK-DAG: mov x0, x4
167}
168
169define dso_local void @check_i128_stackalign(i32 %val0, i32 %val1, i32 %val2, i32 %val3,
170                                   i32 %val4, i32 %val5, i32 %val6, i32 %val7,
171                                   i32 %stack1, i128 %stack2) {
172; CHECK-LABEL: check_i128_stackalign
173    store i128 %stack2, ptr @var128
174    ; Nothing local on stack in current codegen, so first stack is 16 away
175; CHECK-LE: add     x[[REG:[0-9]+]], sp, #16
176; CHECK-LE: ldr {{x[0-9]+}}, [x[[REG]], #8]
177
178    ; Important point is that we address sp+24 for second dword
179
180; CHECK: ldp {{x[0-9]+}}, {{x[0-9]+}}, [sp, #16]
181    ret void
182}
183
184declare void @llvm.memcpy.p0.p0.i32(ptr, ptr, i32, i1)
185
186define dso_local i32 @test_extern() {
187; CHECK-LABEL: test_extern:
188  call void @llvm.memcpy.p0.p0.i32(ptr align 4 undef, ptr align 4 undef, i32 undef, i1 0)
189; CHECK: bl memcpy
190  ret i32 0
191}
192
193
194; A sub-i32 stack argument must be loaded on big endian with ldr{h,b}, not just
195; implicitly extended to a 32-bit load.
196define dso_local i16 @stacked_i16(i32 %val0, i32 %val1, i32 %val2, i32 %val3,
197                        i32 %val4, i32 %val5, i32 %val6, i32 %val7,
198                        i16 %stack1) {
199; CHECK-LABEL: stacked_i16
200  ret i16 %stack1
201}
202