[OpenMP] Initial parsing/sema for the 'omp loop' constructomp-loop

Adds basic parsing/sema/serialization support for the #pragma omp loop
directive.

Differential Revision: https://reviews.llvm.org/D112499

2 files changed, 274 insertions, 0 deletions

diff --git a/clang/test/OpenMP/generic_loop_ast_print.cpp b/clang/test/OpenMP/generic_loop_ast_print.cpp
new file mode 100644
index 000000000000..7f5f53003e40
--- /dev/null
+++ b/clang/test/OpenMP/generic_loop_ast_print.cpp
@@ -0,0 +1,141 @@
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -fopenmp -fopenmp-version=51 \
+// RUN:   -fsyntax-only -verify %s
+
+// expected-no-diagnostics
+
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -fopenmp -fopenmp-version=51 \
+// RUN:   -ast-print %s | FileCheck %s --check-prefix=PRINT
+
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -fopenmp -fopenmp-version=51 \
+// RUN:   -ast-dump  %s | FileCheck %s --check-prefix=DUMP
+
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -fopenmp -fopenmp-version=51 \
+// RUN:   -emit-pch -o %t %s
+
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -fopenmp -fopenmp-version=51 \
+// RUN:   -include-pch %t -ast-dump-all %s | FileCheck %s --check-prefix=DUMP
+
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -fopenmp -fopenmp-version=51 \
+// RUN:   -include-pch %t -ast-print %s | FileCheck %s --check-prefix=PRINT
+
+#ifndef HEADER
+#define HEADER
+
+//PRINT: template <typename T, int C> void templ_foo(T t) {
+//PRINT:   T j, z;
+//PRINT:   #pragma omp loop collapse(C) reduction(+: z) lastprivate(j)
+//PRINT:   for (T i = 0; i < t; ++i)
+//PRINT:       for (j = 0; j < t; ++j)
+//PRINT:           z += i + j;
+//PRINT: }
+//DUMP: FunctionTemplateDecl{{.*}}templ_foo
+//DUMP: TemplateTypeParmDecl{{.*}}T
+//DUMP: NonTypeTemplateParmDecl{{.*}}C
+//DUMP: OMPGenericLoopDirective
+//DUMP: OMPCollapseClause
+//DUMP: DeclRefExpr{{.*}}'C' 'int'
+//DUMP: OMPReductionClause
+//DUMP: DeclRefExpr{{.*}}'z' 'T'
+//DUMP: OMPLastprivateClause
+//DUMP: DeclRefExpr{{.*}}'j' 'T'
+//DUMP: ForStmt
+//DUMP: ForStmt
+
+//PRINT: template<> void templ_foo<int, 2>(int t) {
+//PRINT:     int j, z;
+//PRINT:     #pragma omp loop collapse(2) reduction(+: z) lastprivate(j)
+//PRINT:         for (int i = 0; i < t; ++i)
+//PRINT:             for (j = 0; j < t; ++j)
+//PRINT:                 z += i + j;
+//PRINT: }
+//DUMP: FunctionDecl{{.*}}templ_foo 'void (int)'
+//DUMP: TemplateArgument type 'int'
+//DUMP: TemplateArgument integral 2
+//DUMP: ParmVarDecl{{.*}}'int':'int'
+//DUMP: OMPGenericLoopDirective
+//DUMP: OMPCollapseClause
+//DUMP: ConstantExpr{{.*}}'int'
+//DUMP: value: Int 2
+//DUMP: OMPReductionClause
+//DUMP: DeclRefExpr{{.*}}'z' 'int':'int'
+//DUMP: OMPLastprivateClause
+//DUMP: DeclRefExpr{{.*}}'j' 'int':'int'
+//DUMP: ForStmt
+template <typename T, int C>
+void templ_foo(T t) {
+
+  T j,z;
+  #pragma omp loop collapse(C) reduction(+:z) lastprivate(j)
+  for (T i = 0; i<t; ++i)
+    for (j = 0; j<t; ++j)
+      z += i+j;
+}
+
+
+//PRINT: void test() {
+//DUMP: FunctionDecl {{.*}}test 'void ()'
+void test() {
+  constexpr int N = 100;
+  float MTX[N][N];
+  int aaa[1000];
+
+  //PRINT: #pragma omp target teams distribute parallel for map(tofrom: MTX)
+  //PRINT: #pragma omp loop
+  //DUMP: OMPTargetTeamsDistributeParallelForDirective
+  //DUMP: CapturedStmt
+  //DUMP: ForStmt
+  //DUMP: CompoundStmt
+  //DUMP: OMPGenericLoopDirective
+  #pragma omp target teams distribute parallel for map(MTX)
+  for (auto i = 0; i < N; ++i) {
+    #pragma omp loop
+    for (auto j = 0; j < N; ++j) {
+      MTX[i][j] = 0;
+    }
+  }
+
+  //PRINT: #pragma omp target teams
+  //PRINT: #pragma omp loop
+  //DUMP: OMPTargetTeamsDirective
+  //DUMP: CapturedStmt
+  //DUMP: ForStmt
+  //DUMP: OMPGenericLoopDirective
+  #pragma omp target teams
+  for (int i=0; i<1000; ++i) {
+    #pragma omp loop
+    for (int j=0; j<100; j++) {
+      aaa[i] += i + j;
+    }
+  }
+
+  int j, z, z1;
+  //PRINT: #pragma omp loop collapse(2) private(z) lastprivate(j) order(concurrent) reduction(+: z1)
+  //DUMP: OMPGenericLoopDirective
+  //DUMP: OMPCollapseClause
+  //DUMP: IntegerLiteral{{.*}}2
+  //DUMP: OMPPrivateClause
+  //DUMP-NEXT: DeclRefExpr{{.*}}'z'
+  //DUMP: OMPLastprivateClause
+  //DUMP-NEXT: DeclRefExpr{{.*}}'j'
+  //DUMP: OMPOrderClause
+  //DUMP: OMPReductionClause
+  //DUMP-NEXT: DeclRefExpr{{.*}}'z1'
+  //DUMP: ForStmt
+  //DUMP: ForStmt
+  #pragma omp loop collapse(2) private(z) lastprivate(j) order(concurrent) \
+                   reduction(+:z1)
+  for (auto i = 0; i < N; ++i) {
+    for (j = 0; j < N; ++j) {
+      z = i+j;
+      MTX[i][j] = z;
+      z1 += z;
+    }
+  }
+}
+
+void bar()
+{
+  templ_foo<int,2>(8);
+}
+
+#endif // HEADER
diff --git a/clang/test/OpenMP/generic_loop_messages.cpp b/clang/test/OpenMP/generic_loop_messages.cpp
new file mode 100644
index 000000000000..01838a921330
--- /dev/null
+++ b/clang/test/OpenMP/generic_loop_messages.cpp
@@ -0,0 +1,133 @@
+// RUN: %clang_cc1 -verify -fopenmp -fopenmp-version=51 -Wuninitialized %s
+
+void foo()
+{
+  int i,j,k;
+  int z;
+
+  // expected-error@+2 {{statement after '#pragma omp loop' must be a for loop}}
+  #pragma omp loop
+  i = 0;
+
+  // OpenMP 5.1 [2.22 Nesting of regions]
+  //
+  // A barrier region may not be closely nested inside a worksharing, loop,
+  // task, taskloop, critical, ordered, atomic, or masked region.
+
+  // expected-error@+3 {{region cannot be closely nested inside 'loop' region}}
+  #pragma omp loop
+  for (i=0; i<1000; ++i) {
+    #pragma omp barrier
+  }
+
+  // A masked region may not be closely nested inside a worksharing, loop,
+  // atomic, task, or taskloop region.
+
+  // expected-error@+3 {{region cannot be closely nested inside 'loop' region}}
+  #pragma omp loop
+  for (i=0; i<1000; ++i) {
+    #pragma omp masked filter(2)
+    { }
+  }
+
+  // An ordered region that corresponds to an ordered construct without any
+  // clause or with the threads or depend clause may not be closely nested
+  // inside a critical, ordered, loop, atomic, task, or taskloop region.
+
+  // expected-error@+3 {{region cannot be closely nested inside 'loop' region; perhaps you forget to enclose 'omp ordered' directive into a for or a parallel for region with 'ordered' clause?}}
+  #pragma omp loop
+  for (i=0; i<1000; ++i) {
+    #pragma omp ordered
+    { }
+  }
+
+  // expected-error@+3 {{region cannot be closely nested inside 'loop' region; perhaps you forget to enclose 'omp ordered' directive into a for or a parallel for region with 'ordered' clause?}}
+  #pragma omp loop
+  for (i=0; i<1000; ++i) {
+    #pragma omp ordered threads
+    { }
+  }
+
+  // expected-error@+3 {{region cannot be closely nested inside 'loop' region; perhaps you forget to enclose 'omp ordered' directive into a for or a parallel for region with 'ordered' clause?}}
+  #pragma omp loop
+  for (i=0; i<1000; ++i) {
+    #pragma omp ordered depend(source)
+  }
+
+  // bind clause (not yet implemented)
+
+  // collapse clause
+
+  // expected-error@+4 {{expected 2 for loops after '#pragma omp loop', but found only 1}}
+  // expected-note@+1 {{as specified in 'collapse' clause}}
+  #pragma omp loop collapse(2)
+  for (i=0; i<1000; ++i)
+    z = i+11;
+
+  // expected-error@+1 {{directive '#pragma omp loop' cannot contain more than one 'collapse' clause}}
+  #pragma omp loop collapse(2) collapse(2)
+  for (i=0; i<1000; ++i)
+    for (j=0; j<1000; ++j)
+      z = i+j+11;
+
+  // order clause
+
+  // expected-error@+1 {{expected 'concurrent' in OpenMP clause 'order'}}
+  #pragma omp loop order(foo)
+  for (i=0; i<1000; ++i)
+    z = i+11;
+
+  // private clause
+
+  // expected-error@+1 {{use of undeclared identifier 'undef_var'}}
+  #pragma omp loop private(undef_var)
+  for (i=0; i<1000; ++i)
+    z = i+11;
+
+  // lastprivate
+
+  // A list item may not appear in a lastprivate clause unless it is the loop
+  // iteration variable of a loop that is associated with the construct.
+
+  // expected-error@+1 {{only loop iteration variables are allowed in 'lastprivate' clause in 'omp loop' directives}}
+  #pragma omp loop lastprivate(z)
+  for (i=0; i<1000; ++i) {
+    z = i+11;
+  }
+
+  // expected-error@+1 {{only loop iteration variables are allowed in 'lastprivate' clause in 'omp loop' directives}}
+  #pragma omp loop lastprivate(k) collapse(2)
+  for (i=0; i<1000; ++i)
+    for (j=0; j<1000; ++j)
+      for (k=0; k<1000; ++k)
+        z = i+j+k+11;
+
+  // reduction
+
+  // expected-error@+1 {{use of undeclared identifier 'undef_var'}}
+  #pragma omp loop reduction(+:undef_var)
+  for (i=0; i<1000; ++i)
+    z = i+11;
+}
+
+template <typename T, int C>
+void templ_test(T t) {
+  T i,z;
+
+  // expected-error@+4 {{expected 2 for loops after '#pragma omp loop', but found only 1}}
+  // expected-note@+1 {{as specified in 'collapse' clause}}
+  #pragma omp loop collapse(C)
+  for (i=0; i<1000; ++i)
+    z = i+11;
+
+  // expected-error@+1 {{only loop iteration variables are allowed in 'lastprivate' clause in 'omp loop' directives}}
+  #pragma omp loop lastprivate(z)
+  for (i=0; i<1000; ++i) {
+    z = i+11;
+  }
+}
+
+void bar()
+{
+  templ_test<int, 2>(16); // expected-note {{in instantiation of function template specialization 'templ_test<int, 2>' requested here}}
+}