|
223
|
1 Call may contain unknown parallel regions. Use `__attribute__((assume("omp_no_parallelism")))` to override. [OMP133]
|
|
|
2 ====================================================================================================================
|
|
|
3
|
|
|
4 .. _omp133:
|
|
|
5
|
|
|
6 This analysis remark identifies calls that prevented :ref:`OMP131 <omp131>` from
|
|
|
7 providing the generic-mode kernel with a fully specialized state machine. This
|
|
|
8 remark will identify each call that may contain unknown parallel regions that
|
|
|
9 caused the kernel to require a fallback.
|
|
|
10
|
|
|
11 Examples
|
|
|
12 --------
|
|
|
13
|
|
|
14 This will occur for any generic-mode kernel that may contain unknown parallel
|
|
|
15 regions. This is typically coupled with the :ref:`OMP132 <omp132>` remark.
|
|
|
16
|
|
|
17 .. code-block:: c++
|
|
|
18
|
|
|
19 extern void setup();
|
|
|
20
|
|
|
21 void foo() {
|
|
|
22 #pragma omp target
|
|
|
23 {
|
|
|
24 setup();
|
|
|
25 #pragma omp parallel
|
|
|
26 {
|
|
|
27 work();
|
|
|
28 }
|
|
|
29 }
|
|
|
30 }
|
|
|
31
|
|
|
32 .. code-block:: console
|
|
|
33
|
|
|
34 $ clang++ -fopenmp -fopenmp-targets=nvptx64 -O2 -Rpass-analysis=openmp-opt omp133.cpp
|
|
236
|
35 omp133.cpp:6:5: remark: Call may contain unknown parallel regions. Use
|
|
223
|
36 `__attribute__((assume("omp_no_parallelism")))` to override. [OMP133]
|
|
|
37 setup();
|
|
|
38 ^
|
|
|
39
|
|
|
40 The remark suggests marking the function with the assumption that it contains no
|
|
|
41 parallel regions. If this is done then the kernel will be rewritten with a fully
|
|
|
42 specialized state machine.
|
|
|
43
|
|
|
44 .. code-block:: c++
|
|
|
45
|
|
|
46 __attribute__((assume("omp_no_parallelism"))) extern void setup();
|
|
|
47
|
|
|
48
|
|
|
49 void foo() {
|
|
|
50 #pragma omp target
|
|
|
51 {
|
|
|
52 setup();
|
|
|
53 #pragma omp parallel
|
|
|
54 {
|
|
|
55 work();
|
|
|
56 }
|
|
|
57 }
|
|
|
58 }
|
|
|
59
|
|
|
60 .. code-block:: console
|
|
|
61
|
|
|
62 $ clang++ -fopenmp -fopenmp-targets=nvptx64 -O2 -Rpass=openmp-opt omp133.cpp
|
|
|
63 omp133.cpp:4:1: remark: Rewriting generic-mode kernel with a customized state machine. [OMP131]
|
|
|
64 #pragma omp target
|
|
|
65 ^
|
|
|
66
|
|
|
67 Diagnostic Scope
|
|
|
68 ----------------
|
|
|
69
|
|
|
70 OpenMP target offloading analysis remark.
|
