Fix for issue #425

Author: mbudiu-vmw

ir/base.def

@@ -174,7 +174,11 @@ class Annotation {
     Annotation(ID n, intmax_t v) : name(n) {
         expr.push_back(new IR::Constant(v)); }
     /// Predefined annotations used by the compiler
-    static const cstring nameAnnotation;
+    static const cstring nameAnnotation;  /// indicates the control-plane name
+    static const cstring tableOnlyAnnotation;  /// action cannot be a default_action
+    static const cstring defaultOnlyAnnotation;  /// action can only be a default_action
+    static const cstring atomicAnnotation;  /// code should be executed atomically
+    static const cstring hiddenAnnotation;  /// object should not be exposed to the control-plane
     toString{ return cstring("@") + name; }
     validate{ BUG_CHECK(!name.name.isNullOrEmpty(), "empty annotation name"); }
 }

ir/type.cpp

@@ -32,6 +32,10 @@ const IR::ID IR::Type_Table::hit = ID("hit");
 const IR::ID IR::Type_Table::action_run = ID("action_run");
 
 const cstring IR::Annotation::nameAnnotation = "name";
+const cstring IR::Annotation::tableOnlyAnnotation = "tableonly";
+const cstring IR::Annotation::defaultOnlyAnnotation = "defaultonly";
+const cstring IR::Annotation::atomicAnnotation = "atomic";
+const cstring IR::Annotation::hiddenAnnotation = "hidden";
 
 std::map<int, const IR::Type_Bits*> *Type_Bits::signedTypes = nullptr;
 std::map<int, const IR::Type_Bits*> *Type_Bits::unsignedTypes = nullptr;

midend/actionSynthesis.cpp

@@ -75,7 +75,11 @@ const IR::Node* DoMoveActionsToTables::postorder(IR::MethodCallStatement* statem
     auto props = new IR::TableProperties(nm);
     // Synthesize a new table
     cstring tblName = IR::ID(refMap->newName(cstring("tbl_") + ac->action->name.name), nullptr);
-    auto tbl = new IR::P4Table(tblName, props);
+
+    auto annos = new IR::Annotations();
+    annos->add(new IR::Annotation(IR::Annotation::hiddenAnnotation,
+                                  IR::Vector<IR::Expression>()));
+    auto tbl = new IR::P4Table(tblName, annos, props);
     tables.push_back(tbl);
 
     // Table invocation statement
@@ -197,7 +201,11 @@ const IR::Statement* DoSynthesizeActions::createAction(const IR::Statement* toAd
         b->push_back(toAdd);
         body = new IR::BlockStatement(toAdd->srcInfo, b);
     }
-    auto action = new IR::P4Action(name, new IR::ParameterList(), body);
+
+    auto annos = new IR::Annotations();
+    annos->add(new IR::Annotation(IR::Annotation::hiddenAnnotation,
+                                  IR::Vector<IR::Expression>()));
+    auto action = new IR::P4Action(name, annos, new IR::ParameterList(), body);
     actions.push_back(action);
     auto actpath = new IR::PathExpression(name);
     auto repl = new IR::MethodCallExpression(actpath);

midend/actionSynthesis.h

@@ -22,31 +22,41 @@ limitations under the License.
 
 namespace P4 {
 
-// Policy which selects the control blocks where action
-// synthesis is applied.
+/**
+Policy which selects the control blocks where action
+synthesis is applied.
+*/
 class ActionSynthesisPolicy {
  public:
     virtual ~ActionSynthesisPolicy() {}
-    // If the policy returns true the control block is processed,
-    // otherwise it is left unchanged.
+    /**
+       If the policy returns true the control block is processed,
+       otherwise it is left unchanged.
+    */
     virtual bool convert(const IR::P4Control* control) const = 0;
 };
 
-// Convert direct action calls to table invocations.
-// control c() {
-//   action x(in bit b) { ... }
-//   apply { x(e); }
-// }
-// turns into
-// control c() {
-//   action x(in bit b) { ... }
-//   table _tmp() {
-//     actions = { x(e); }
-//     const default_action = x();
-//   }
-//   apply { _tmp.apply(); }
-// }
-// For this to work all variable declarations must have been moved to the beginning.
+/**
+Convert direct action calls to table invocations.
+
+control c() {
+  action x(in bit b) { ... }
+  apply { x(e); }
+}
+
+turns into
+
+control c() {
+  action x(in bit b) { ... }
+  table _tmp() {
+    actions = { x(e); }
+    const default_action = x();
+  }
+  apply { _tmp.apply(); }
+}
+
+For this to work all variable declarations must have been moved to the beginning.
+*/
 class DoMoveActionsToTables : public Transform {
     ReferenceMap* refMap;
     TypeMap*      typeMap;
@@ -66,17 +76,23 @@ class DoMoveActionsToTables : public Transform {
     const IR::Node* postorder(IR::MethodCallStatement* statement) override;
 };
 
-// Convert some statements into action invocations by synthesizing new actions.
-// E.g.
-// control c(inout bit x) {
-//    apply { x = 1; }
-// }
-// is converted to:
-// control c(inout bit x) {
-//    action act() { x = 1; }
-//    apply { act(); }
-// }
-// For this to work all variable declarations must have been moved to the beginning.
+/**
+Convert some statements into action invocations by synthesizing new actions.
+E.g.
+
+control c(inout bit x) {
+   apply { x = 1; }
+}
+
+is converted to:
+
+control c(inout bit x) {
+   action act() { x = 1; }
+   apply { act(); }
+}
+
+For this to work all variable declarations must have been moved to the beginning.
+*/
 class DoSynthesizeActions : public Transform {
     ReferenceMap* refMap;
     TypeMap*      typeMap;

testdata/p4_14_samples_outputs/exact_match_mask1-midend.p4

@@ -45,10 +45,10 @@ control ingress(inout headers hdr, inout metadata meta, inout standard_metadata_
         }
         default_action = NoAction_0();
     }
-    action act() {
+    @hidden action act() {
         key_0 = hdr.data.f1 & 32w0xff00ff;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }

testdata/p4_14_samples_outputs/hit-midend.p4

@@ -77,19 +77,19 @@ control ingress(inout headers hdr, inout metadata meta, inout standard_metadata_
         }
         default_action = NoAction_5();
     }
-    action act() {
+    @hidden action act() {
         tmp_0 = true;
     }
-    action act_0() {
+    @hidden action act_0() {
         tmp_0 = false;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }
         const default_action = act();
     }
-    table tbl_act_0 {
+    @hidden table tbl_act_0 {
         actions = {
             act_0();
         }

testdata/p4_14_samples_outputs/hitmiss-midend.p4

@@ -85,19 +85,19 @@ control ingress(inout headers hdr, inout metadata meta, inout standard_metadata_
         }
         default_action = NoAction_5();
     }
-    action act() {
+    @hidden action act() {
         tmp_0 = true;
     }
-    action act_0() {
+    @hidden action act_0() {
         tmp_0 = false;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }
         const default_action = act();
     }
-    table tbl_act_0 {
+    @hidden table tbl_act_0 {
         actions = {
             act_0();
         }

testdata/p4_14_samples_outputs/miss-midend.p4

@@ -77,19 +77,19 @@ control ingress(inout headers hdr, inout metadata meta, inout standard_metadata_
         }
         default_action = NoAction_5();
     }
-    action act() {
+    @hidden action act() {
         tmp_0 = true;
     }
-    action act_0() {
+    @hidden action act_0() {
         tmp_0 = false;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }
         const default_action = act();
     }
-    table tbl_act_0 {
+    @hidden table tbl_act_0 {
         actions = {
             act_0();
         }

testdata/p4_16_samples_outputs/action-synth-midend.p4

@@ -16,7 +16,7 @@ parser ParserI(packet_in pk, out H hdr, inout M meta, inout standard_metadata_t
 control IngressI(inout H hdr, inout M meta, inout standard_metadata_t smeta) {
     @name("aux.a") action aux_a() {
     }
-    table tbl_aux_a {
+    @hidden table tbl_aux_a {
         actions = {
             aux_a();
         }

testdata/p4_16_samples_outputs/action_call_ebpf-midend.p4

@@ -15,16 +15,16 @@ control pipe(inout Headers_t headers, out bool pass) {
     @name("Reject") action Reject_0() {
         pass = x;
     }
-    action act() {
+    @hidden action act() {
         x = true;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }
         const default_action = act();
     }
-    table tbl_Reject {
+    @hidden table tbl_Reject {
         actions = {
             Reject_0();
         }

testdata/p4_16_samples_outputs/action_param1-midend.p4

@@ -2,7 +2,7 @@ control c(inout bit<32> x) {
     @name("a") action a_0() {
         x = 32w15;
     }
-    table tbl_a {
+    @hidden table tbl_a {
         actions = {
             a_0();
         }

testdata/p4_16_samples_outputs/arith-inline-bmv2-midend.p4

@@ -52,10 +52,10 @@ control ingress(inout Headers h, inout Meta m, inout standard_metadata_t sm) {
         }
         const default_action = c_add();
     }
-    action act() {
+    @hidden action act() {
         sm.egress_spec = 9w0;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }

testdata/p4_16_samples_outputs/arith2-inline-bmv2-midend.p4

@@ -43,37 +43,37 @@ control deparser(packet_out b, in Headers h) {
 }
 
 control ingress(inout Headers h, inout Meta m, inout standard_metadata_t sm) {
-    action act() {
+    @hidden action act() {
         h.h.c = 8w0;
     }
-    action act_0() {
+    @hidden action act_0() {
         h.h.c = 8w1;
     }
-    action act_1() {
+    @hidden action act_1() {
         sm.egress_spec = 9w0;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }
         const default_action = act();
     }
-    table tbl_act_0 {
+    @hidden table tbl_act_0 {
         actions = {
             act_0();
         }
         const default_action = act_0();
     }
-    table tbl_act_1 {
+    @hidden table tbl_act_1 {
         actions = {
             act_1();
         }
         const default_action = act_1();
     }
     apply {
-        if (h.h.a < h.h.b)
+        if (h.h.a < h.h.b) 
             tbl_act.apply();
-        else
+        else 
             tbl_act_0.apply();
         tbl_act_1.apply();
     }

testdata/p4_16_samples_outputs/array_field-midend.p4

@@ -7,12 +7,12 @@ control c(out H[2] h);
 package top(c _c);
 control my(out H[2] s) {
     bit<1> tmp_1;
-    action act() {
+    @hidden action act() {
         s[32w0].z = 1w1;
         s[32w1].z = 1w0;
         tmp_1 = f(s[32w0].z, 1w0);
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }

testdata/p4_16_samples_outputs/clone-bmv2-midend.p4

@@ -14,10 +14,10 @@ parser ParserI(packet_in pk, out H hdr, inout M meta, inout standard_metadata_t
 }
 
 control IngressI(inout H hdr, inout M meta, inout standard_metadata_t smeta) {
-    action act() {
+    @hidden action act() {
         clone(CloneType.I2E, smeta.clone_spec);
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }

testdata/p4_16_samples_outputs/complex-midend.p4

@@ -2,12 +2,12 @@ extern bit<32> f(in bit<32> x);
 control c(inout bit<32> r) {
     bit<32> tmp_2;
     bit<32> tmp_4;
-    action act() {
+    @hidden action act() {
         tmp_2 = f(32w5);
         tmp_4 = f(tmp_2);
         r = tmp_4;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }

testdata/p4_16_samples_outputs/complex1-midend.p4

@@ -4,14 +4,14 @@ control c(inout bit<32> r) {
     bit<32> tmp_8;
     bit<32> tmp_10;
     bit<32> tmp_12;
-    action act() {
+    @hidden action act() {
         tmp_6 = f(32w5, 32w2);
         tmp_8 = f(32w2, 32w3);
         tmp_10 = f(32w6, tmp_8);
         tmp_12 = f(tmp_6, tmp_10);
         r = tmp_12;
     }
-    table tbl_act {
+    @hidden table tbl_act {
         actions = {
             act();
         }