1) Claiming support for "dispatch" construct.

2) Changed comments in transformDispatchDirective() in SemaOpenMP.cpp
3) Adding checks in clang/test/OpenMP/dispatch_messages.cpp for
        a) depend clause
        b) nocontext, novariants & depend clauses occuring in the same line of dispatch construct.
4) Removing debugging statements (kept under #if 0 and #endif) in OMPContext.h.

Author: Sunil Kuravinakop

clang/docs/OpenMPSupport.rst

@@ -314,6 +314,8 @@ implementation.
 +------------------------------+--------------------------------------------------------------+--------------------------+-----------------------------------------------------------------------+
 | misc                         | dispatch construct and function variant argument adjustment  | :part:`worked on`        | D99537, D99679                                                        |
 +------------------------------+--------------------------------------------------------------+--------------------------+-----------------------------------------------------------------------+
+| misc                         | dispatch construct   | :part:`worked on`        |  |
++------------------------------+--------------------------------------------------------------+--------------------------+-----------------------------------------------------------------------+
 | misc                         | assumes directives                                           | :part:`worked on`        |                                                                       |
 +------------------------------+--------------------------------------------------------------+--------------------------+-----------------------------------------------------------------------+
 | misc                         | assume directive                                             | :good:`done`             |                                                                       |

clang/lib/Sema/SemaOpenMP.cpp

@@ -6142,6 +6142,8 @@ StmtResult SemaOpenMP::transformDispatchDirective(
 
     const OMPNovariantsClause *NoVariantsC =
         OMPExecutableDirective::getSingleClause<OMPNovariantsClause>(Clauses);
+    // The following example explains the code transformation in the code
+    //
     // #pragma omp dispatch novariants(c2) depend(out: x)
     // foo();
     // becomes:
@@ -6150,7 +6152,7 @@ StmtResult SemaOpenMP::transformDispatchDirective(
     //    foo();
     // } else {
     //    #pragma omp dispatch
-    //    foo(); <--- foo() is replaced with foo_variant() in CodeGen
+    //    foo();
     // }
     Expr *Cond = getInitialExprFromCapturedExpr(NoVariantsC->getCondition());
     StmtResult ThenStmt =
@@ -6179,12 +6181,15 @@ StmtResult SemaOpenMP::transformDispatchDirective(
     const OMPNocontextClause *NoContextC =
         OMPExecutableDirective::getSingleClause<OMPNocontextClause>(Clauses);
     Expr *Cond = getInitialExprFromCapturedExpr(NoContextC->getCondition());
+    // The following example explains the code transformation in the code
+    //
     // #pragma omp dispatch depend(out: x) nocontext(c2)
     // foo();
     // becomes:
     // #pragma omp taskwait depend(out: x)
     // if (c2) {
-    //    foo();
+    //    foo(); <=== transformation explained clearly in
+    //    	         replaceWithNewTraitsOrDirectCall()
     // } else {
     //    #pragma omp dispatch
     //    foo();
@@ -6215,7 +6220,7 @@ StmtResult SemaOpenMP::transformDispatchDirective(
     // Only:
     // #pragma omp dispatch depend(out: x)
     // foo();
-    // to
+    // becomes:
     // #pragma omp taskwait depend(out: x)
     // foo();
     StmtResult FinalStmts =

clang/test/OpenMP/dispatch_messages.cpp

@@ -64,6 +64,48 @@ void testit_one(int dnum) {
   // expected-error@+1 {{use of undeclared identifier 'x'}}
   #pragma omp dispatch nocontext(x)
   disp_call();
+
+  bool c1 = false;
+  bool c2 = true;
+  int a = 3, b=4;
+  int output;
+ 
+  // expected-error@+1 {{expected '(' after 'depend'}}
+  #pragma omp dispatch depend
+  disp_call();
+
+  // expected-error@+4 {{expected ')'}}
+  // expected-note@+3 {{to match this '('}}
+  // expected-error@+2 {{expected depend modifier(iterator) or 'in', 'out', 'inout', 'mutexinoutset', 'depobj' or 'inoutset' in OpenMP clause 'depend'}}
+  // expected-warning@+1 {{missing ':' after dependency type}}
+  #pragma omp dispatch depend(
+  disp_call();
+
+  // expected-error@+4 {{expected ')'}}
+  // expected-note@+3 {{to match this '('}}
+  // expected-error@+2 {{expected depend modifier(iterator) or 'in', 'out', 'inout', 'mutexinoutset', 'depobj' or 'inoutset' in OpenMP clause 'depend'}}
+  // expected-warning@+1 {{missing ':' after dependency type}}
+  #pragma omp dispatch depend(a
+  disp_call();
+
+  // expected-error@+2 {{expected depend modifier(iterator) or 'in', 'out', 'inout', 'mutexinoutset', 'depobj' or 'inoutset' in OpenMP clause 'depend'}}
+  // expected-warning@+1 {{missing ':' after dependency type}}
+  #pragma omp dispatch depend(a)
+  disp_call();
+
+  // expected-error@+1 {{use of undeclared identifier 'z'}}
+  #pragma omp dispatch depend(in:z)
+  disp_call();
+
+  #pragma omp dispatch depend(in:b)
+  output = disp_call();
+
+  #pragma omp dispatch depend(in:b) depend(in:a)
+  output = disp_call();
+
+  // expected-warning@+1 {{only 'novariants' clause is supported when 'novariants' & 'nocontext' clauses occur on the same dispatch construct}}
+  #pragma omp dispatch nocontext(c1) novariants(c2) depend(inout:a)
+  disp_call();
 }
 
 void testit_two() {

llvm/include/llvm/Frontend/OpenMP/OMPContext.h

@@ -141,12 +141,6 @@ struct VariantMatchInfo {
       ISATraits.push_back(RawString);
 
     RequiredTraits.set(unsigned(Property));
-#if 0
-    unsigned int i = 0;
-    for (unsigned Bit : RequiredTraits.set_bits()) {
-	i++;
-    }
-#endif
     if (Set == TraitSet::construct)
       ConstructTraits.push_back(Property);
   }