xref: /aosp_15_r20/external/llvm/test/CodeGen/AArch64/tail-call.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)
1; RUN: llc -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu -tailcallopt | FileCheck %s
2
3declare fastcc void @callee_stack0()
4declare fastcc void @callee_stack8([8 x i32], i64)
5declare fastcc void @callee_stack16([8 x i32], i64, i64)
6declare extern_weak fastcc void @callee_weak()
7
8define fastcc void @caller_to0_from0() nounwind {
9; CHECK-LABEL: caller_to0_from0:
10; CHECK-NEXT: // BB
11
12  tail call fastcc void @callee_stack0()
13  ret void
14
15; CHECK-NEXT: b callee_stack0
16}
17
18define fastcc void @caller_to0_from8([8 x i32], i64) {
19; CHECK-LABEL: caller_to0_from8:
20
21  tail call fastcc void @callee_stack0()
22  ret void
23
24; CHECK: add sp, sp, #16
25; CHECK-NEXT: b callee_stack0
26}
27
28define fastcc void @caller_to8_from0() {
29; CHECK-LABEL: caller_to8_from0:
30; CHECK: sub sp, sp, #32
31
32; Key point is that the "42" should go #16 below incoming stack
33; pointer (we didn't have arg space to reuse).
34  tail call fastcc void @callee_stack8([8 x i32] undef, i64 42)
35  ret void
36
37; CHECK: str {{x[0-9]+}}, [sp, #16]!
38; CHECK-NEXT: b callee_stack8
39}
40
41define fastcc void @caller_to8_from8([8 x i32], i64 %a) {
42; CHECK-LABEL: caller_to8_from8:
43; CHECK: sub sp, sp, #16
44
45; Key point is that the "%a" should go where at SP on entry.
46  tail call fastcc void @callee_stack8([8 x i32] undef, i64 42)
47  ret void
48
49; CHECK: str {{x[0-9]+}}, [sp, #16]!
50; CHECK-NEXT: b callee_stack8
51}
52
53define fastcc void @caller_to16_from8([8 x i32], i64 %a) {
54; CHECK-LABEL: caller_to16_from8:
55; CHECK: sub sp, sp, #16
56
57; Important point is that the call reuses the "dead" argument space
58; above %a on the stack. If it tries to go below incoming-SP then the
59; callee will not deallocate the space, even in fastcc.
60  tail call fastcc void @callee_stack16([8 x i32] undef, i64 42, i64 2)
61
62; CHECK: stp {{x[0-9]+}}, {{x[0-9]+}}, [sp, #16]!
63; CHECK-NEXT: b callee_stack16
64  ret void
65}
66
67
68define fastcc void @caller_to8_from24([8 x i32], i64 %a, i64 %b, i64 %c) {
69; CHECK-LABEL: caller_to8_from24:
70; CHECK: sub sp, sp, #16
71
72; Key point is that the "%a" should go where at #16 above SP on entry.
73  tail call fastcc void @callee_stack8([8 x i32] undef, i64 42)
74  ret void
75
76; CHECK: str {{x[0-9]+}}, [sp, #32]!
77; CHECK-NEXT: b callee_stack8
78}
79
80
81define fastcc void @caller_to16_from16([8 x i32], i64 %a, i64 %b) {
82; CHECK-LABEL: caller_to16_from16:
83; CHECK: sub sp, sp, #16
84
85; Here we want to make sure that both loads happen before the stores:
86; otherwise either %a or %b will be wrongly clobbered.
87  tail call fastcc void @callee_stack16([8 x i32] undef, i64 %b, i64 %a)
88  ret void
89
90; CHECK: ldp {{x[0-9]+}}, {{x[0-9]+}}, [sp, #16]
91; CHECK: stp {{x[0-9]+}}, {{x[0-9]+}}, [sp, #16]!
92; CHECK-NEXT: b callee_stack16
93}
94
95
96; Weakly-referenced extern functions cannot be tail-called, as AAELF does
97; not define the behaviour of branch instructions to undefined weak symbols.
98define fastcc void @caller_weak() {
99; CHECK-LABEL: caller_weak:
100; CHECK: bl callee_weak
101  tail call void @callee_weak()
102  ret void
103}
104
105declare { [2 x float] } @get_vec2()
106
107define { [3 x float] } @test_add_elem() {
108; CHECK-LABEL: test_add_elem:
109; CHECK: bl get_vec2
110; CHECK: fmov s2, #1.0
111; CHECK: ret
112
113  %call = tail call { [2 x float] } @get_vec2()
114  %arr = extractvalue { [2 x float] } %call, 0
115  %arr.0 = extractvalue [2 x float] %arr, 0
116  %arr.1 = extractvalue [2 x float] %arr, 1
117
118  %res.0 = insertvalue { [3 x float] } undef, float %arr.0, 0, 0
119  %res.01 = insertvalue { [3 x float] } %res.0, float %arr.1, 0, 1
120  %res.012 = insertvalue { [3 x float] } %res.01, float 1.000000e+00, 0, 2
121  ret { [3 x float] } %res.012
122}
123
124declare double @get_double()
125define { double, [2 x double] } @test_mismatched_insert() {
126; CHECK-LABEL: test_mismatched_insert:
127; CHECK: bl get_double
128; CHECK: bl get_double
129; CHECK: bl get_double
130; CHECK: ret
131
132  %val0 = call double @get_double()
133  %val1 = call double @get_double()
134  %val2 = tail call double @get_double()
135
136  %res.0 = insertvalue { double, [2 x double] } undef, double %val0, 0
137  %res.01 = insertvalue { double, [2 x double] } %res.0, double %val1, 1, 0
138  %res.012 = insertvalue { double, [2 x double] } %res.01, double %val2, 1, 1
139
140  ret { double, [2 x double] } %res.012
141}
142