[OpenMP][FIX] Do not crash trying to print a missing (demangled) user condition

[ABataev]

clang/lib/AST/OpenMPClause.cpp

2204–2208

Why it can be nullptr if it is required to be set?

clang/test/AST/ast-dump-openmp-begin-declare-variant_13.c

28–30

Does this comment match the test?

[jdoerfert]

clang/lib/AST/OpenMPClause.cpp

2204–2208

It took me a while to realize why it is OK. This can only happen when we pretty print the name after we demangled it from the function. We could consider annotating the variant with the TI somehow but we never needed to so far.

clang/test/AST/ast-dump-openmp-begin-declare-variant_13.c

28–30

Leftover, good catch.

[jdoerfert]

Remove leftover comment

[JonChesterfield]

Seems OK to me as a local fix. I'm not sure about encoding 'missing condition' as 0, but that's a preexisting choice.

clang/lib/AST/OpenMPClause.cpp

for (const OMPTraitSelector &Selector : Set.Selectors) {
       isValidTraitSelectorForTraitSet(
           Selector.Kind, Set.Kind, AllowsTraitScore, RequiresProperty);
 
       if (!RequiresProperty)
         continue;
 
       OS << "(";
       if (Selector.Kind == TraitSelector::user_condition) {
+        if (Selector.ScoreOrCondition)
           Selector.ScoreOrCondition->printPretty(OS, nullptr, Policy);
+        else
+          OS << "...";
       } else {
 
         if (Selector.ScoreOrCondition) {
           OS << "score(";
           Selector.ScoreOrCondition->printPretty(OS, nullptr, Policy);
           OS << "): ";
         }
 
         bool FirstProperty = true;

clang/test/AST/ast-dump-openmp-begin-declare-variant_13.c

+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fopenmp -verify -ast-dump %s       | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fopenmp -verify -ast-dump %s -x c++| FileCheck %s
+// expected-no-diagnostics
+
+int also_before(void) {
+  return 1;
+}
+
+#pragma omp begin declare variant match(user = {condition(1)})
+int also_after(void) {
+  return 0;
+}
+int also_before(void) {
+  return 0;
+}
+#pragma omp end declare variant
+
+int also_after(void) {
+  return 2;
+}
+
+int test() {
+  // Should return 0.
+  return also_after() + also_before();
+}
+
+// CHECK:      |-FunctionDecl [[ADDR_0:0x[a-z0-9]*]] <{{.*}}, line:7:1> line:5:5 used also_before 'int ({{.*}})'
+// CHECK-NEXT: | |-CompoundStmt [[ADDR_1:0x[a-z0-9]*]] <col:23, line:7:1>
+// CHECK-NEXT: | | `-ReturnStmt [[ADDR_2:0x[a-z0-9]*]] <line:6:3, col:10>
+// CHECK-NEXT: | |   `-IntegerLiteral [[ADDR_3:0x[a-z0-9]*]] <col:10> 'int' 1
+// CHECK-NEXT: | `-OMPDeclareVariantAttr [[ADDR_4:0x[a-z0-9]*]] <<invalid sloc>> Implicit user={condition(1)}
+// CHECK-NEXT: |   `-DeclRefExpr [[ADDR_5:0x[a-z0-9]*]] <line:13:1> 'int ({{.*}})' {{.*}}Function [[ADDR_6:0x[a-z0-9]*]] 'also_before[user={condition(...)}]' 'int ({{.*}})'
+// CHECK-NEXT: |-FunctionDecl [[ADDR_7:0x[a-z0-9]*]] <line:10:1, col:20> col:5 implicit used also_after 'int ({{.*}})'
+// CHECK-NEXT: | `-OMPDeclareVariantAttr [[ADDR_8:0x[a-z0-9]*]] <<invalid sloc>> Implicit user={condition(1)}
+// CHECK-NEXT: |   `-DeclRefExpr [[ADDR_9:0x[a-z0-9]*]] <col:1> 'int ({{.*}})' {{.*}}Function [[ADDR_10:0x[a-z0-9]*]] 'also_after[user={condition(...)}]' 'int ({{.*}})'
+// CHECK-NEXT: |-FunctionDecl [[ADDR_10]] <col:1, line:12:1> line:10:1 also_after[user={condition(...)}] 'int ({{.*}})'
+// CHECK-NEXT: | `-CompoundStmt [[ADDR_11:0x[a-z0-9]*]] <col:22, line:12:1>
+// CHECK-NEXT: |   `-ReturnStmt [[ADDR_12:0x[a-z0-9]*]] <line:11:3, col:10>
+// CHECK-NEXT: |     `-IntegerLiteral [[ADDR_13:0x[a-z0-9]*]] <col:10> 'int' 0
+// CHECK-NEXT: |-FunctionDecl [[ADDR_6]] <line:13:1, line:15:1> line:13:1 also_before[user={condition(...)}] 'int ({{.*}})'
+// CHECK-NEXT: | `-CompoundStmt [[ADDR_14:0x[a-z0-9]*]] <col:23, line:15:1>
+// CHECK-NEXT: |   `-ReturnStmt [[ADDR_15:0x[a-z0-9]*]] <line:14:3, col:10>
+// CHECK-NEXT: |     `-IntegerLiteral [[ADDR_16:0x[a-z0-9]*]] <col:10> 'int' 0
+// CHECK-NEXT: |-FunctionDecl [[ADDR_17:0x[a-z0-9]*]] prev [[ADDR_7]] <line:18:1, line:20:1> line:18:5 used also_after 'int ({{.*}})'
+// CHECK-NEXT: | |-CompoundStmt [[ADDR_18:0x[a-z0-9]*]] <col:22, line:20:1>
+// CHECK-NEXT: | | `-ReturnStmt [[ADDR_19:0x[a-z0-9]*]] <line:19:3, col:10>
+// CHECK-NEXT: | |   `-IntegerLiteral [[ADDR_20:0x[a-z0-9]*]] <col:10> 'int' 2
+// CHECK-NEXT: | `-OMPDeclareVariantAttr [[ADDR_21:0x[a-z0-9]*]] <<invalid sloc>> Inherited Implicit user={condition(1)}
+// CHECK-NEXT: |   `-DeclRefExpr [[ADDR_9]] <line:10:1> 'int ({{.*}})' {{.*}}Function [[ADDR_10]] 'also_after[user={condition(...)}]' 'int ({{.*}})'
+// CHECK-NEXT: `-FunctionDecl [[ADDR_22:0x[a-z0-9]*]] <line:22:1, line:25:1> line:22:5 test 'int ({{.*}})'
+// CHECK-NEXT:   `-CompoundStmt [[ADDR_23:0x[a-z0-9]*]] <col:12, line:25:1>
+// CHECK-NEXT:     `-ReturnStmt [[ADDR_24:0x[a-z0-9]*]] <line:24:3, col:37>
+// CHECK-NEXT:       `-BinaryOperator [[ADDR_25:0x[a-z0-9]*]] <col:10, col:37> 'int' '+'
+// CHECK-NEXT:         |-PseudoObjectExpr [[ADDR_26:0x[a-z0-9]*]] <col:10, col:21> 'int'
+// CHECK-NEXT:         | |-CallExpr [[ADDR_27:0x[a-z0-9]*]] <col:10, col:21> 'int'
+// CHECK-NEXT:         | | `-ImplicitCastExpr [[ADDR_28:0x[a-z0-9]*]] <col:10> 'int (*)({{.*}})' <FunctionToPointerDecay>
+// CHECK-NEXT:         | |   `-DeclRefExpr [[ADDR_29:0x[a-z0-9]*]] <col:10> 'int ({{.*}})' {{.*}}Function [[ADDR_17]] 'also_after' 'int ({{.*}})'
+// CHECK-NEXT:         | `-CallExpr [[ADDR_30:0x[a-z0-9]*]] <line:10:1, line:24:21> 'int'
+// CHECK-NEXT:         |   `-ImplicitCastExpr [[ADDR_31:0x[a-z0-9]*]] <line:10:1> 'int (*)({{.*}})' <FunctionToPointerDecay>
+// CHECK-NEXT:         |     `-DeclRefExpr [[ADDR_9]] <col:1> 'int ({{.*}})' {{.*}}Function [[ADDR_10]] 'also_after[user={condition(...)}]' 'int ({{.*}})'
+// CHECK-NEXT:         `-PseudoObjectExpr [[ADDR_32:0x[a-z0-9]*]] <line:24:25, col:37> 'int'
+// CHECK-NEXT:           |-CallExpr [[ADDR_33:0x[a-z0-9]*]] <col:25, col:37> 'int'
+// CHECK-NEXT:           | `-ImplicitCastExpr [[ADDR_34:0x[a-z0-9]*]] <col:25> 'int (*)({{.*}})' <FunctionToPointerDecay>
+// CHECK-NEXT:           |   `-DeclRefExpr [[ADDR_35:0x[a-z0-9]*]] <col:25> 'int ({{.*}})' {{.*}}Function [[ADDR_0]] 'also_before' 'int ({{.*}})'
+// CHECK-NEXT:           `-CallExpr [[ADDR_36:0x[a-z0-9]*]] <line:13:1, line:24:37> 'int'
+// CHECK-NEXT:             `-ImplicitCastExpr [[ADDR_37:0x[a-z0-9]*]] <line:13:1> 'int (*)({{.*}})' <FunctionToPointerDecay>
+// CHECK-NEXT:               `-DeclRefExpr [[ADDR_5]] <col:1> 'int ({{.*}})' {{.*}}Function [[ADDR_6]] 'also_before[user={condition(...)}]' 'int ({{.*}})'