[clang] [OpenACC] Implement 'num_workers' clause for compute constructs (PR #89151)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,133 @@
+// RUN: %clang_cc1 %s -fopenacc -verify
+
+struct NotConvertible{} NC;
+struct Incomplete *SomeIncomplete; // #INCOMPLETE
+enum E{} SomeE;
+enum class E2{} SomeE2;
+
+struct CorrectConvert {
+  operator int();
+} Convert;
+
+struct ExplicitConvertOnly {
+  explicit operator int() const; // #EXPL_CONV
+} Explicit;
+
+struct AmbiguousConvert{
+  operator int(); // #AMBIG_INT
+  operator short(); // #AMBIG_SHORT
+  operator float();
+} Ambiguous;
+
+void Test() {
+#pragma acc parallel num_workers(1)
+  while(1);
+#pragma acc kernels num_workers(1)
+  while(1);
+
+  // expected-error at +1{{OpenACC clause 'num_workers' requires expression of integer type ('struct NotConvertible' invalid}}
+#pragma acc parallel num_workers(NC)
+  while(1);
+
+  // expected-error at +2{{OpenACC integer expression has incomplete class type 'struct Incomplete'}}
+  // expected-note@#INCOMPLETE{{forward declaration of 'Incomplete'}}
+#pragma acc kernels num_workers(*SomeIncomplete)
+  while(1);
+
+#pragma acc parallel num_workers(SomeE)
+  while(1);
+
+  // expected-error at +1{{OpenACC clause 'num_workers' requires expression of integer type ('enum E2' invalid}}
+#pragma acc kernels num_workers(SomeE2)
+  while(1);
+
+#pragma acc parallel num_workers(Convert)
+  while(1);
+
+  // expected-error at +2{{OpenACC integer expression type 'struct ExplicitConvertOnly' requires explicit conversion to 'int'}}
+  // expected-note@#EXPL_CONV{{conversion to integral type 'int'}}
+#pragma acc kernels num_workers(Explicit)
+  while(1);
+
+  // expected-error at +3{{multiple conversions from expression type 'struct AmbiguousConvert' to an integral type}}
+  // expected-note@#AMBIG_INT{{conversion to integral type 'int'}}
+  // expected-note@#AMBIG_SHORT{{conversion to integral type 'short'}}
+#pragma acc parallel num_workers(Ambiguous)
+  while(1);
+}
+
+struct HasInt {
+  using IntTy = int;
+  using ShortTy = short;
+  static constexpr int value = 1;
+  static constexpr AmbiguousConvert ACValue;
+  static constexpr ExplicitConvertOnly EXValue;
+
+  operator char();
+};
+
+template<typename T>
+void TestInst() {
+
+  // expected-error at +1{{no member named 'Invalid' in 'HasInt'}}
+#pragma acc parallel num_workers(HasInt::Invalid)
+  while (1);
+
+  // expected-error at +2{{no member named 'Invalid' in 'HasInt'}}
+  // expected-note@#INST{{in instantiation of function template specialization 'TestInst<HasInt>' requested here}}
+#pragma acc kernels num_workers(T::Invalid)
+  while (1);
+
+  // expected-error at +3{{multiple conversions from expression type 'const AmbiguousConvert' to an integral type}}
+  // expected-note@#AMBIG_INT{{conversion to integral type 'int'}}
+  // expected-note@#AMBIG_SHORT{{conversion to integral type 'short'}}
+#pragma acc parallel num_workers(HasInt::ACValue)
+  while (1);
+
+  // expected-error at +3{{multiple conversions from expression type 'const AmbiguousConvert' to an integral type}}
+  // expected-note@#AMBIG_INT{{conversion to integral type 'int'}}
+  // expected-note@#AMBIG_SHORT{{conversion to integral type 'short'}}
+#pragma acc kernels num_workers(T::ACValue)
+  while (1);
+
+  // expected-error at +2{{OpenACC integer expression type 'const ExplicitConvertOnly' requires explicit conversion to 'int'}}
+  // expected-note@#EXPL_CONV{{conversion to integral type 'int'}}
+#pragma acc parallel num_workers(HasInt::EXValue)
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erichkeane wrote:

Note: this is expected to diagnose the above error/note 2x until this patch is committed: https://github.com/llvm/llvm-project/pull/89142

as it uses the same infrastructure.  I'll ensure these are committed in the correct order.

https://github.com/llvm/llvm-project/pull/89151