xref: /aosp_15_r20/external/clang/test/SemaCUDA/function-overload.cu (revision 67e74705e28f6214e480b399dd47ea732279e315)
1 // REQUIRES: x86-registered-target
2 // REQUIRES: nvptx-registered-target
3 
4 // RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fsyntax-only -verify %s
5 // RUN: %clang_cc1 -triple nvptx64-nvidia-cuda -fsyntax-only -fcuda-is-device -verify %s
6 
7 #include "Inputs/cuda.h"
8 
9 // Opaque return types used to check that we pick the right overloads.
10 struct HostReturnTy {};
11 struct HostReturnTy2 {};
12 struct DeviceReturnTy {};
13 struct DeviceReturnTy2 {};
14 struct HostDeviceReturnTy {};
15 struct TemplateReturnTy {};
16 
17 typedef HostReturnTy (*HostFnPtr)();
18 typedef DeviceReturnTy (*DeviceFnPtr)();
19 typedef HostDeviceReturnTy (*HostDeviceFnPtr)();
20 typedef void (*GlobalFnPtr)();  // __global__ functions must return void.
21 
22 // CurrentReturnTy is {HostReturnTy,DeviceReturnTy} during {host,device}
23 // compilation.
24 #ifdef __CUDA_ARCH__
25 typedef DeviceReturnTy CurrentReturnTy;
26 #else
27 typedef HostReturnTy CurrentReturnTy;
28 #endif
29 
30 // CurrentFnPtr is a function pointer to a {host,device} function during
31 // {host,device} compilation.
32 typedef CurrentReturnTy (*CurrentFnPtr)();
33 
34 // Host and unattributed functions can't be overloaded.
hh()35 __host__ void hh() {} // expected-note {{previous definition is here}}
hh()36 void hh() {} // expected-error {{redefinition of 'hh'}}
37 
38 // H/D overloading is OK.
dh()39 __host__ HostReturnTy dh() { return HostReturnTy(); }
dh()40 __device__ DeviceReturnTy dh() { return DeviceReturnTy(); }
41 
42 // H/HD and D/HD are not allowed.
hdh()43 __host__ __device__ int hdh() { return 0; } // expected-note {{previous definition is here}}
hdh()44 __host__ int hdh() { return 0; }            // expected-error {{redefinition of 'hdh'}}
45 
hhd()46 __host__ int hhd() { return 0; }            // expected-note {{previous definition is here}}
hhd()47 __host__ __device__ int hhd() { return 0; } // expected-error {{redefinition of 'hhd'}}
48 // expected-warning@-1 {{attribute declaration must precede definition}}
49 // expected-note@-3 {{previous definition is here}}
50 
hdd()51 __host__ __device__ int hdd() { return 0; } // expected-note {{previous definition is here}}
hdd()52 __device__ int hdd() { return 0; }          // expected-error {{redefinition of 'hdd'}}
53 
dhd()54 __device__ int dhd() { return 0; }          // expected-note {{previous definition is here}}
dhd()55 __host__ __device__ int dhd() { return 0; } // expected-error {{redefinition of 'dhd'}}
56 // expected-warning@-1 {{attribute declaration must precede definition}}
57 // expected-note@-3 {{previous definition is here}}
58 
59 // Same tests for extern "C" functions.
chh()60 extern "C" __host__ int chh() { return 0; } // expected-note {{previous definition is here}}
chh()61 extern "C" int chh() { return 0; }          // expected-error {{redefinition of 'chh'}}
62 
63 // H/D overloading is OK.
cdh()64 extern "C" __device__ DeviceReturnTy cdh() { return DeviceReturnTy(); }
cdh()65 extern "C" __host__ HostReturnTy cdh() { return HostReturnTy(); }
66 
67 // H/HD and D/HD overloading is not allowed.
chhd1()68 extern "C" __host__ __device__ int chhd1() { return 0; } // expected-note {{previous definition is here}}
chhd1()69 extern "C" __host__ int chhd1() { return 0; }            // expected-error {{redefinition of 'chhd1'}}
70 
chhd2()71 extern "C" __host__ int chhd2() { return 0; }            // expected-note {{previous definition is here}}
chhd2()72 extern "C" __host__ __device__ int chhd2() { return 0; } // expected-error {{redefinition of 'chhd2'}}
73 // expected-warning@-1 {{attribute declaration must precede definition}}
74 // expected-note@-3 {{previous definition is here}}
75 
76 // Helper functions to verify calling restrictions.
d()77 __device__ DeviceReturnTy d() { return DeviceReturnTy(); }
78 // expected-note@-1 1+ {{'d' declared here}}
79 // expected-note@-2 1+ {{candidate function not viable: call to __device__ function from __host__ function}}
80 // expected-note@-3 0+ {{candidate function not viable: call to __device__ function from __host__ __device__ function}}
81 
h()82 __host__ HostReturnTy h() { return HostReturnTy(); }
83 // expected-note@-1 1+ {{'h' declared here}}
84 // expected-note@-2 1+ {{candidate function not viable: call to __host__ function from __device__ function}}
85 // expected-note@-3 0+ {{candidate function not viable: call to __host__ function from __host__ __device__ function}}
86 // expected-note@-4 1+ {{candidate function not viable: call to __host__ function from __global__ function}}
87 
g()88 __global__ void g() {}
89 // expected-note@-1 1+ {{'g' declared here}}
90 // expected-note@-2 1+ {{candidate function not viable: call to __global__ function from __device__ function}}
91 // expected-note@-3 0+ {{candidate function not viable: call to __global__ function from __host__ __device__ function}}
92 // expected-note@-4 1+ {{candidate function not viable: call to __global__ function from __global__ function}}
93 
cd()94 extern "C" __device__ DeviceReturnTy cd() { return DeviceReturnTy(); }
95 // expected-note@-1 1+ {{'cd' declared here}}
96 // expected-note@-2 1+ {{candidate function not viable: call to __device__ function from __host__ function}}
97 // expected-note@-3 0+ {{candidate function not viable: call to __device__ function from __host__ __device__ function}}
98 
ch()99 extern "C" __host__ HostReturnTy ch() { return HostReturnTy(); }
100 // expected-note@-1 1+ {{'ch' declared here}}
101 // expected-note@-2 1+ {{candidate function not viable: call to __host__ function from __device__ function}}
102 // expected-note@-3 0+ {{candidate function not viable: call to __host__ function from __host__ __device__ function}}
103 // expected-note@-4 1+ {{candidate function not viable: call to __host__ function from __global__ function}}
104 
hostf()105 __host__ void hostf() {
106   DeviceFnPtr fp_d = d;         // expected-error {{reference to __device__ function 'd' in __host__ function}}
107   DeviceReturnTy ret_d = d();   // expected-error {{no matching function for call to 'd'}}
108   DeviceFnPtr fp_cd = cd;       // expected-error {{reference to __device__ function 'cd' in __host__ function}}
109   DeviceReturnTy ret_cd = cd(); // expected-error {{no matching function for call to 'cd'}}
110 
111   HostFnPtr fp_h = h;
112   HostReturnTy ret_h = h();
113   HostFnPtr fp_ch = ch;
114   HostReturnTy ret_ch = ch();
115 
116   HostFnPtr fp_dh = dh;
117   HostReturnTy ret_dh = dh();
118   HostFnPtr fp_cdh = cdh;
119   HostReturnTy ret_cdh = cdh();
120 
121   GlobalFnPtr fp_g = g;
122   g(); // expected-error {{call to global function g not configured}}
123   g<<<0, 0>>>();
124 }
125 
devicef()126 __device__ void devicef() {
127   DeviceFnPtr fp_d = d;
128   DeviceReturnTy ret_d = d();
129   DeviceFnPtr fp_cd = cd;
130   DeviceReturnTy ret_cd = cd();
131 
132   HostFnPtr fp_h = h;         // expected-error {{reference to __host__ function 'h' in __device__ function}}
133   HostReturnTy ret_h = h();   // expected-error {{no matching function for call to 'h'}}
134   HostFnPtr fp_ch = ch;       // expected-error {{reference to __host__ function 'ch' in __device__ function}}
135   HostReturnTy ret_ch = ch(); // expected-error {{no matching function for call to 'ch'}}
136 
137   DeviceFnPtr fp_dh = dh;
138   DeviceReturnTy ret_dh = dh();
139   DeviceFnPtr fp_cdh = cdh;
140   DeviceReturnTy ret_cdh = cdh();
141 
142   GlobalFnPtr fp_g = g; // expected-error {{reference to __global__ function 'g' in __device__ function}}
143   g(); // expected-error {{no matching function for call to 'g'}}
144   g<<<0,0>>>(); // expected-error {{reference to __global__ function 'g' in __device__ function}}
145 }
146 
globalf()147 __global__ void globalf() {
148   DeviceFnPtr fp_d = d;
149   DeviceReturnTy ret_d = d();
150   DeviceFnPtr fp_cd = cd;
151   DeviceReturnTy ret_cd = cd();
152 
153   HostFnPtr fp_h = h;         // expected-error {{reference to __host__ function 'h' in __global__ function}}
154   HostReturnTy ret_h = h();   // expected-error {{no matching function for call to 'h'}}
155   HostFnPtr fp_ch = ch;       // expected-error {{reference to __host__ function 'ch' in __global__ function}}
156   HostReturnTy ret_ch = ch(); // expected-error {{no matching function for call to 'ch'}}
157 
158   DeviceFnPtr fp_dh = dh;
159   DeviceReturnTy ret_dh = dh();
160   DeviceFnPtr fp_cdh = cdh;
161   DeviceReturnTy ret_cdh = cdh();
162 
163   GlobalFnPtr fp_g = g; // expected-error {{reference to __global__ function 'g' in __global__ function}}
164   g(); // expected-error {{no matching function for call to 'g'}}
165   g<<<0,0>>>(); // expected-error {{reference to __global__ function 'g' in __global__ function}}
166 }
167 
hostdevicef()168 __host__ __device__ void hostdevicef() {
169   DeviceFnPtr fp_d = d;
170   DeviceReturnTy ret_d = d();
171   DeviceFnPtr fp_cd = cd;
172   DeviceReturnTy ret_cd = cd();
173 
174   HostFnPtr fp_h = h;
175   HostReturnTy ret_h = h();
176   HostFnPtr fp_ch = ch;
177   HostReturnTy ret_ch = ch();
178 
179   CurrentFnPtr fp_dh = dh;
180   CurrentReturnTy ret_dh = dh();
181   CurrentFnPtr fp_cdh = cdh;
182   CurrentReturnTy ret_cdh = cdh();
183 
184   GlobalFnPtr fp_g = g;
185 #if defined(__CUDA_ARCH__)
186   // expected-error@-2 {{reference to __global__ function 'g' in __host__ __device__ function}}
187 #endif
188   g();
189   g<<<0,0>>>();
190 #if !defined(__CUDA_ARCH__)
191   // expected-error@-3 {{call to global function g not configured}}
192 #else
193   // expected-error@-5 {{no matching function for call to 'g'}}
194   // expected-error@-5 {{reference to __global__ function 'g' in __host__ __device__ function}}
195 #endif  // __CUDA_ARCH__
196 }
197 
198 // Test for address of overloaded function resolution in the global context.
199 HostFnPtr fp_h = h;
200 HostFnPtr fp_ch = ch;
201 CurrentFnPtr fp_dh = dh;
202 CurrentFnPtr fp_cdh = cdh;
203 GlobalFnPtr fp_g = g;
204 
205 
206 // Test overloading of destructors
207 // Can't mix H and unattributed destructors
208 struct d_h {
~d_hd_h209   ~d_h() {} // expected-note {{previous declaration is here}}
~d_hd_h210   __host__ ~d_h() {} // expected-error {{destructor cannot be redeclared}}
211 };
212 
213 // H/D overloading is OK
214 struct d_dh {
~d_dhd_dh215   __device__ ~d_dh() {}
~d_dhd_dh216   __host__ ~d_dh() {}
217 };
218 
219 // HD is OK
220 struct d_hd {
~d_hdd_hd221   __host__ __device__ ~d_hd() {}
222 };
223 
224 // Mixing H/D and HD is not allowed.
225 struct d_dhhd {
~d_dhhdd_dhhd226   __device__ ~d_dhhd() {}
~d_dhhdd_dhhd227   __host__ ~d_dhhd() {} // expected-note {{previous declaration is here}}
~d_dhhdd_dhhd228   __host__ __device__ ~d_dhhd() {} // expected-error {{destructor cannot be redeclared}}
229 };
230 
231 struct d_hhd {
~d_hhdd_hhd232   __host__ ~d_hhd() {} // expected-note {{previous declaration is here}}
~d_hhdd_hhd233   __host__ __device__ ~d_hhd() {} // expected-error {{destructor cannot be redeclared}}
234 };
235 
236 struct d_hdh {
~d_hdhd_hdh237   __host__ __device__ ~d_hdh() {} // expected-note {{previous declaration is here}}
~d_hdhd_hdh238   __host__ ~d_hdh() {} // expected-error {{destructor cannot be redeclared}}
239 };
240 
241 struct d_dhd {
~d_dhdd_dhd242   __device__ ~d_dhd() {} // expected-note {{previous declaration is here}}
~d_dhdd_dhd243   __host__ __device__ ~d_dhd() {} // expected-error {{destructor cannot be redeclared}}
244 };
245 
246 struct d_hdd {
~d_hddd_hdd247   __host__ __device__ ~d_hdd() {} // expected-note {{previous declaration is here}}
~d_hddd_hdd248   __device__ ~d_hdd() {} // expected-error {{destructor cannot be redeclared}}
249 };
250 
251 // Test overloading of member functions
252 struct m_h {
253   void operator delete(void *ptr); // expected-note {{previous declaration is here}}
254   __host__ void operator delete(void *ptr); // expected-error {{class member cannot be redeclared}}
255 };
256 
257 // D/H overloading is OK
258 struct m_dh {
259   __device__ void operator delete(void *ptr);
260   __host__ void operator delete(void *ptr);
261 };
262 
263 // HD by itself is OK
264 struct m_hd {
265   __device__ __host__ void operator delete(void *ptr);
266 };
267 
268 struct m_hhd {
operator deletem_hhd269   __host__ void operator delete(void *ptr) {} // expected-note {{previous declaration is here}}
operator deletem_hhd270   __host__ __device__ void operator delete(void *ptr) {} // expected-error {{class member cannot be redeclared}}
271 };
272 
273 struct m_hdh {
operator deletem_hdh274   __host__ __device__ void operator delete(void *ptr) {} // expected-note {{previous declaration is here}}
operator deletem_hdh275   __host__ void operator delete(void *ptr) {} // expected-error {{class member cannot be redeclared}}
276 };
277 
278 struct m_dhd {
operator deletem_dhd279   __device__ void operator delete(void *ptr) {} // expected-note {{previous declaration is here}}
operator deletem_dhd280   __host__ __device__ void operator delete(void *ptr) {} // expected-error {{class member cannot be redeclared}}
281 };
282 
283 struct m_hdd {
operator deletem_hdd284   __host__ __device__ void operator delete(void *ptr) {} // expected-note {{previous declaration is here}}
operator deletem_hdd285   __device__ void operator delete(void *ptr) {} // expected-error {{class member cannot be redeclared}}
286 };
287 
288 // __global__ functions can't be overloaded based on attribute
289 // difference.
290 struct G {
291   friend void friend_of_g(G &arg);
292 private:
293   int x;
294 };
friend_of_g(G & arg)295 __global__ void friend_of_g(G &arg) { int x = arg.x; } // expected-note {{previous definition is here}}
friend_of_g(G & arg)296 void friend_of_g(G &arg) { int x = arg.x; } // expected-error {{redefinition of 'friend_of_g'}}
297 
298 // HD functions are sometimes allowed to call H or D functions -- this
299 // is an artifact of the source-to-source splitting performed by nvcc
300 // that we need to mimic. During device mode compilation in nvcc, host
301 // functions aren't present at all, so don't participate in
302 // overloading. But in clang, H and D functions are present in both
303 // compilation modes. Clang normally uses the target attribute as a
304 // tiebreaker between overloads with otherwise identical priority, but
305 // in order to match nvcc's behavior, we sometimes need to wholly
306 // discard overloads that would not be present during compilation
307 // under nvcc.
308 
template_vs_function(T arg)309 template <typename T> TemplateReturnTy template_vs_function(T arg) {
310   return TemplateReturnTy();
311 }
template_vs_function(float arg)312 __device__ DeviceReturnTy template_vs_function(float arg) {
313   return DeviceReturnTy();
314 }
315 
316 // Here we expect to call the templated function during host compilation, even
317 // if -fcuda-disable-target-call-checks is passed, and even though C++ overload
318 // rules prefer the non-templated function.
test_host_device_calls_template(void)319 __host__ __device__ void test_host_device_calls_template(void) {
320 #ifdef __CUDA_ARCH__
321   typedef DeviceReturnTy ExpectedReturnTy;
322 #else
323   typedef TemplateReturnTy ExpectedReturnTy;
324 #endif
325 
326   ExpectedReturnTy ret1 = template_vs_function(1.0f);
327   ExpectedReturnTy ret2 = template_vs_function(2.0);
328 }
329 
330 // Calls from __host__ and __device__ functions should always call the
331 // overloaded function that matches their mode.
test_host_calls_template_fn()332 __host__ void test_host_calls_template_fn() {
333   TemplateReturnTy ret1 = template_vs_function(1.0f);
334   TemplateReturnTy ret2 = template_vs_function(2.0);
335 }
336 
test_device_calls_template_fn()337 __device__ void test_device_calls_template_fn() {
338   DeviceReturnTy ret1 = template_vs_function(1.0f);
339   DeviceReturnTy ret2 = template_vs_function(2.0);
340 }
341 
342 // If we have a mix of HD and H-only or D-only candidates in the overload set,
343 // normal C++ overload resolution rules apply first.
template_vs_hd_function(T arg)344 template <typename T> TemplateReturnTy template_vs_hd_function(T arg) {
345   return TemplateReturnTy();
346 }
template_vs_hd_function(float arg)347 __host__ __device__ HostDeviceReturnTy template_vs_hd_function(float arg) {
348   return HostDeviceReturnTy();
349 }
350 
test_host_device_calls_hd_template()351 __host__ __device__ void test_host_device_calls_hd_template() {
352   HostDeviceReturnTy ret1 = template_vs_hd_function(1.0f);
353   TemplateReturnTy ret2 = template_vs_hd_function(1);
354 }
355 
test_host_calls_hd_template()356 __host__ void test_host_calls_hd_template() {
357   HostDeviceReturnTy ret1 = template_vs_hd_function(1.0f);
358   TemplateReturnTy ret2 = template_vs_hd_function(1);
359 }
360 
test_device_calls_hd_template()361 __device__ void test_device_calls_hd_template() {
362   HostDeviceReturnTy ret1 = template_vs_hd_function(1.0f);
363   // Host-only function template is not callable with strict call checks,
364   // so for device side HD function will be the only choice.
365   HostDeviceReturnTy ret2 = template_vs_hd_function(1);
366 }
367 
368 // Check that overloads still work the same way on both host and
369 // device side when the overload set contains only functions from one
370 // side of compilation.
device_only_function(int arg)371 __device__ DeviceReturnTy device_only_function(int arg) { return DeviceReturnTy(); }
device_only_function(float arg)372 __device__ DeviceReturnTy2 device_only_function(float arg) { return DeviceReturnTy2(); }
host_only_function(int arg)373 __host__ HostReturnTy host_only_function(int arg) { return HostReturnTy(); }
host_only_function(float arg)374 __host__ HostReturnTy2 host_only_function(float arg) { return HostReturnTy2(); }
375 
test_host_device_single_side_overloading()376 __host__ __device__ void test_host_device_single_side_overloading() {
377   DeviceReturnTy ret1 = device_only_function(1);
378   DeviceReturnTy2 ret2 = device_only_function(1.0f);
379   HostReturnTy ret3 = host_only_function(1);
380   HostReturnTy2 ret4 = host_only_function(1.0f);
381 }
382