[clang] [Clang] [Parser] Support [[omp::assume]] (PR #84582)

[via cfe-commits]

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@@ -12,3 +14,18 @@ void f9(void) __attribute__((assume("omp_no_openmp", "omp_no_openmp"))); // expe
 
 int g1 __attribute__((assume(0))); // expected-error {{expected string literal as argument of 'assume' attribute}}
 int g2 __attribute__((assume("omp_no_openmp"))); // expected-warning {{'assume' attribute only applies to functions and Objective-C methods}}
+
+#else
+[[omp::assume(3)]] void f1(); // expected-error {{expected string literal as argument of 'assume' attribute}}
+[[omp::assume(int)]] void f2(); // expected-error {{expected string literal as argument of 'assume' attribute}}
+[[omp::assume(for)]] void f3(); // expected-error {{expected string literal as argument of 'assume' attribute}}
+[[omp::assume("QQQQ")]] void f4(); // expected-warning {{unknown assumption string 'QQQQ'; attribute is potentially ignored}}
+[[omp::assume("omp_no_openmp")]] void f5();
+[[omp::assume("omp_noopenmp")]] void f6(); // expected-warning {{unknown assumption string 'omp_noopenmp' may be misspelled; attribute is potentially ignored, did you mean 'omp_no_openmp'?}}
+[[omp::assume("omp_no_openmp_routine")]] void f7(); // expected-warning {{unknown assumption string 'omp_no_openmp_routine' may be misspelled; attribute is potentially ignored, did you mean 'omp_no_openmp_routines'?}}
+[[omp::assume("omp_no_openmp1")]] void f8(); // expected-warning {{unknown assumption string 'omp_no_openmp1' may be misspelled; attribute is potentially ignored, did you mean 'omp_no_openmp'?}}
+[[omp::assume("omp_no_openmp", "omp_no_openmp")]] void f9(); // expected-error {{'assume' attribute takes one argument}}
+
+[[omp::assume(3)]] int g1; // expected-error {{expected string literal as argument of 'assume' attribute}}
+[[omp::assume("omp_no_openmp")]] int g2; // expected-warning {{'assume' attribute only applies to functions and Objective-C methods}}
+#endif
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Sirraide wrote:

My intent here was that we’d eventually remove `__attribute__((assume))` and with it the other branch of the `#if`, but we haven’t really come to a decision as to how to handle that yet, and it probably does make more sense to put it there, so I’ll move it to the omp tests.

https://github.com/llvm/llvm-project/pull/84582