[OpenMP] Fix C-only clang assert on parsing use_allocator clause of target directive

[carlo.bertolli]

Summary

The parser code assumes building with C++ compiler and asserts when using clang (not clang++) on C file. I made the code dependent on input language. This shows up for amdgpu target.

[ABataev]

Tests?

[carlo.bertolli]

Ah! I forgot to add a reference to a filed bugzilla:
https://bugs.llvm.org/show_bug.cgi?id=50619

I will add a test

[carlo.bertolli]

[OpenMP] Add test for C language of target uses_allocators clause

[ABataev]

LG

[JonChesterfield]

Nice, thanks. I guess we already have an equivalent test in c++?

[carlo.bertolli]

In D103899#2817081, @JonChesterfield wrote:

Nice, thanks. I guess we already have an equivalent test in c++?

Correct: check clang/test/target_uses_allocators_{messages,codegen}.cpp

[carlo.bertolli]

@ABataev can you please merge this for me? I still have to ask for commit privileges.

clang/lib/Parse/ParseOpenMP.cpp

OMPClause *Parser::ParseOpenMPUsesAllocatorClause(OpenMPDirectiveKind DKind) {
   ConsumeAnyToken();
 
   // Parse '('.
   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
   if (T.expectAndConsume(diag::err_expected_lparen_after, "uses_allocator"))
     return nullptr;
   SmallVector<Sema::UsesAllocatorsData, 4> Data;
   do {
-    ExprResult Allocator = ParseCXXIdExpression();
+    ExprResult Allocator =
+        getLangOpts().CPlusPlus ? ParseCXXIdExpression() : ParseExpression();
     if (Allocator.isInvalid()) {
       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
                 StopBeforeMatch);
       break;
     }
     Sema::UsesAllocatorsData &D = Data.emplace_back();
     D.Allocator = Allocator.get();
     if (Tok.is(tok::l_paren)) {
       BalancedDelimiterTracker T(*this, tok::l_paren,
                                  tok::annot_pragma_openmp_end);
       T.consumeOpen();
-      ExprResult AllocatorTraits = ParseCXXIdExpression();
+      ExprResult AllocatorTraits =
+          getLangOpts().CPlusPlus ? ParseCXXIdExpression() : ParseExpression();
       T.consumeClose();
       if (AllocatorTraits.isInvalid()) {
         SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
                   StopBeforeMatch);
         break;
       }
       D.AllocatorTraits = AllocatorTraits.get();
       D.LParenLoc = T.getOpenLocation();

clang/test/OpenMP/target_uses_allocators.c

+// Test host codegen.
+// RUN: %clang_cc1 -verify -fopenmp -fopenmp-version=50  -triple powerpc64le-unknown-unknown -fopenmp-targets=powerpc64le-ibm-linux-gnu -emit-llvm %s -o - | FileCheck %s --check-prefix CHECK --check-prefix CHECK-64
+// RUN: %clang_cc1 -fopenmp -fopenmp-version=50 -x c++ -triple powerpc64le-unknown-unknown -fopenmp-targets=powerpc64le-ibm-linux-gnu -emit-pch -o %t %s
+// RUN: %clang_cc1 -fopenmp -fopenmp-version=50 -x c++ -triple powerpc64le-unknown-unknown -fopenmp-targets=powerpc64le-ibm-linux-gnu
+
+// expected-no-diagnostics
+#ifndef HEADER
+#define HEADER
+
+enum omp_allocator_handle_t {
+  omp_null_allocator = 0,
+  omp_default_mem_alloc = 1,
+  omp_large_cap_mem_alloc = 2,
+  omp_const_mem_alloc = 3,
+  omp_high_bw_mem_alloc = 4,
+  omp_low_lat_mem_alloc = 5,
+  omp_cgroup_mem_alloc = 6,
+  omp_pteam_mem_alloc = 7,
+  omp_thread_mem_alloc = 8,
+  KMP_ALLOCATOR_MAX_HANDLE = __UINTPTR_MAX__
+};
+
+// CHECK: define {{.*}}[[FIE:@.+]]()
+void fie() {
+  int x;
+  #pragma omp target uses_allocators(omp_null_allocator) allocate(omp_null_allocator: x) firstprivate(x)
+  {}
+  #pragma omp target uses_allocators(omp_default_mem_alloc) allocate(omp_default_mem_alloc: x) firstprivate(x)
+  {}
+  #pragma omp target uses_allocators(omp_large_cap_mem_alloc) allocate(omp_large_cap_mem_alloc: x) firstprivate(x)
+  {}
+  #pragma omp target uses_allocators(omp_const_mem_alloc) allocate(omp_const_mem_alloc: x) firstprivate(x)
+  {}
+  #pragma omp target uses_allocators(omp_high_bw_mem_alloc) allocate(omp_high_bw_mem_alloc: x) firstprivate(x)
+  {}
+  #pragma omp target uses_allocators(omp_low_lat_mem_alloc) allocate(omp_low_lat_mem_alloc: x) firstprivate(x)
+  {}
+  #pragma omp target uses_allocators(omp_cgroup_mem_alloc) allocate(omp_cgroup_mem_alloc: x) firstprivate(x)
+  {}
+  #pragma omp target uses_allocators(omp_pteam_mem_alloc) allocate(omp_pteam_mem_alloc: x) firstprivate(x)
+  {}
+}
+
+#endif