Comparisons of list expressions, structure-valued expressions, tuples…

… and structs #3057 * I corrected the code so that the compiler bug does not occur when comparing structures of unknown type, but to report an error * I enabled a comparison between the structure/list expression so that the cast can be put on either side. Before this change, if the cast was on the right side of the comparison operator error was reported. * Added tests which verify the above
p4lang · mihaibudiu · Mar 17, 2022 · Mar 10, 2022 · Mar 15, 2022 · e054f2b691affbec14f65e10f0f5d1b9a416e23a
commit e054f2b691affbec14f65e10f0f5d1b9a416e23a
diff --git a/frontends/p4/typeChecking/typeChecker.cpp b/frontends/p4/typeChecking/typeChecker.cpp
@@ -1653,7 +1653,8 @@ bool TypeInference::compare(const IR::Node* errorPosition,
 
     bool defined = false;
     if (typeMap->equivalent(ltype, rtype) &&
-        (!ltype->is<IR::Type_Void>() && !ltype->is<IR::Type_Varbits>())) {
+        (!ltype->is<IR::Type_Void>() && !ltype->is<IR::Type_Varbits>())
+         && !ltype->to<IR::Type_UnknownStruct>()) {
         defined = true;
     } else if (ltype->is<IR::Type_Base>() && rtype->is<IR::Type_Base>() &&
                typeMap->equivalent(ltype, rtype)) {
@@ -1673,14 +1674,19 @@ bool TypeInference::compare(const IR::Node* errorPosition,
         auto rs = rtype->to<IR::Type_UnknownStruct>();
         if (ls != nullptr || rs != nullptr) {
             if (ls != nullptr && rs != nullptr) {
-                typeError("%1%: cannot compare initializers with unknown types", errorPosition);
+                typeError("%1%: cannot compare structure-valued expressions with unknown types",
+                          errorPosition);
                 return false;
             }
 
             bool lcst = isCompileTimeConstant(compare->left);
             bool rcst = isCompileTimeConstant(compare->right);
-
-            auto tvs = unify(errorPosition, ltype, rtype);
+            TypeVariableSubstitution* tvs;
+            if (ls == nullptr) {
+                tvs = unify(errorPosition, ltype, rtype);
+            } else {
+                tvs = unify(errorPosition, rtype, ltype);
+            }
             if (tvs == nullptr)
                 return false;
             if (!tvs->isIdentity()) {

diff --git a/testdata/p4_16_errors/issue3057-1.p4 b/testdata/p4_16_errors/issue3057-1.p4
@@ -0,0 +1,17 @@
+struct S {
+    bit<32> a;
+    bit<32> b;
+}
+
+control proto();
+package top(proto _p);
+control c() {
+    apply {
+        bool b1 = { 1, 2 } == { 1, 2 };
+        bool b2 = {a = 32w1,b = 32w2} == {a = 32w1,b = 32w2};
+        bool b2_ = {a = 1,b = 2} == {a = 1,b = 2};
+    }
+}
+
+top(c()) main;
+
diff --git a/testdata/p4_16_errors_outputs/issue3057-1.p4 b/testdata/p4_16_errors_outputs/issue3057-1.p4
@@ -0,0 +1,17 @@
+struct S {
+    bit<32> a;
+    bit<32> b;
+}
+
+control proto();
+package top(proto _p);
+control c() {
+    apply {
+        bool b1 = { 1, 2 } == { 1, 2 };
+        bool b2 = {a = 32w1,b = 32w2} == {a = 32w1,b = 32w2};
+        bool b2_ = {a = 1,b = 2} == {a = 1,b = 2};
+    }
+}
+
+top(c()) main;
+
diff --git a/testdata/p4_16_errors_outputs/issue3057-1.p4-stderr b/testdata/p4_16_errors_outputs/issue3057-1.p4-stderr
@@ -0,0 +1,6 @@
+issue3057-1.p4(11): [--Werror=type-error] error: ==: cannot compare structure-valued expressions with unknown types
+        bool b2 = {a = 32w1,b = 32w2} == {a = 32w1,b = 32w2};
+                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+issue3057-1.p4(12): [--Werror=type-error] error: ==: cannot compare structure-valued expressions with unknown types
+        bool b2_ = {a = 1,b = 2} == {a = 1,b = 2};
+                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/testdata/p4_16_samples/issue3057-2.p4 b/testdata/p4_16_samples/issue3057-2.p4
@@ -0,0 +1,35 @@
+/*
+Copyright 2016 VMware, Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+struct S {
+    bit<32> a;
+    bit<32> b;
+}
+
+
+control proto();
+package top(proto _p);
+
+control c() {
+    apply {
+
+        bool b5 = (S) { a = 1, b = 2 } == { a = 1, b = 2 };
+        bool b5_ = { a = 1, b = 2 } == (S) { a = 1, b = 2 };
+
+    }
+}
+
+top(c()) main;
diff --git a/testdata/p4_16_samples_outputs/issue3057-2-first.p4 b/testdata/p4_16_samples_outputs/issue3057-2-first.p4
@@ -0,0 +1,16 @@
+struct S {
+    bit<32> a;
+    bit<32> b;
+}
+
+control proto();
+package top(proto _p);
+control c() {
+    apply {
+        bool b5 = (S){a = 32w1,b = 32w2} == (S){a = 32w1,b = 32w2};
+        bool b5_ = (S){a = 32w1,b = 32w2} == (S){a = 32w1,b = 32w2};
+    }
+}
+
+top(c()) main;
+
diff --git a/testdata/p4_16_samples_outputs/issue3057-2-frontend.p4 b/testdata/p4_16_samples_outputs/issue3057-2-frontend.p4
@@ -0,0 +1,14 @@
+struct S {
+    bit<32> a;
+    bit<32> b;
+}
+
+control proto();
+package top(proto _p);
+control c() {
+    apply {
+    }
+}
+
+top(c()) main;
+
diff --git a/testdata/p4_16_samples_outputs/issue3057-2-midend.p4 b/testdata/p4_16_samples_outputs/issue3057-2-midend.p4
@@ -0,0 +1,14 @@
+struct S {
+    bit<32> a;
+    bit<32> b;
+}
+
+control proto();
+package top(proto _p);
+control c() {
+    apply {
+    }
+}
+
+top(c()) main;
+
diff --git a/testdata/p4_16_samples_outputs/issue3057-2.p4 b/testdata/p4_16_samples_outputs/issue3057-2.p4
@@ -0,0 +1,16 @@
+struct S {
+    bit<32> a;
+    bit<32> b;
+}
+
+control proto();
+package top(proto _p);
+control c() {
+    apply {
+        bool b5 = (S){a = 1,b = 2} == {a = 1,b = 2};
+        bool b5_ = {a = 1,b = 2} == (S){a = 1,b = 2};
+    }
+}
+
+top(c()) main;
+
diff --git a/testdata/p4_16_samples_outputs/issue3057-2.p4-stderr b/testdata/p4_16_samples_outputs/issue3057-2.p4-stderr
diff --git a/testdata/p4_16_samples_outputs/issue3057-2.p4.entries.txt b/testdata/p4_16_samples_outputs/issue3057-2.p4.entries.txt
diff --git a/testdata/p4_16_samples_outputs/issue3057-2.p4.p4info.txt b/testdata/p4_16_samples_outputs/issue3057-2.p4.p4info.txt
@@ -0,0 +1,3 @@
+pkg_info {
+  arch: "v1model"
+}