Not all returns in parsers are disallowed

backends/bmv2/common/controlFlowGraph.h

@@ -50,7 +50,7 @@ class CFG final : public IHasDbPrint {
         bool checkSame(const EdgeSet& other) const;
         /// Check if this destination appears in this edgeset.
         /// Importantly, a TableNode is a destination if it points to
-        /// the same table as an existin destination (pointer equality
+        /// the same table as an existing destination (pointer equality
         /// is not enough).
         bool isDestination(const CFG::Node* destination) const;
     };

frontends/p4/methodInstance.cpp

@@ -17,6 +17,7 @@ limitations under the License.
 #include "methodInstance.h"
 #include "ir/ir.h"
 #include "frontends/p4/typeChecking/typeChecker.h"
+#include "frontends/p4/evaluator/substituteParameters.h"
 
 namespace P4 {
 
@@ -124,6 +125,12 @@ MethodInstance::resolve(const IR::MethodCallExpression* mce, DeclarationLookup*
     return nullptr;  // unreachable
 }
 
+const IR::P4Action* ActionCall::specialize(ReferenceMap* refMap) const {
+    SubstituteParameters sp(refMap, &substitution, new TypeVariableSubstitution());
+    auto result = action->apply(sp);
+    return result->to<IR::P4Action>();
+}
+
 ConstructorCall*
 ConstructorCall::resolve(const IR::ConstructorCallExpression* cce,
                          DeclarationLookup* refMap, TypeMap* typeMap) {

frontends/p4/methodInstance.h

@@ -192,6 +192,9 @@ class ActionCall final : public MethodInstance {
     friend class MethodInstance;
  public:
     const IR::P4Action* action;
+    /// Generate a version of the action where the parameters in the
+    /// substitution have been replaced with the arguments.
+    const IR::P4Action* specialize(ReferenceMap* refMap) const;
 };
 
 /**

frontends/p4/validateParsedProgram.cpp

@@ -223,10 +223,13 @@ void ValidateParsedProgram::postorder(const IR::SwitchStatement* statement) {
 
 /// Return statements are not allowed in parsers
 void ValidateParsedProgram::postorder(const IR::ReturnStatement* statement) {
-    auto inParser = findContext<IR::P4Parser>();
-    if (inParser != nullptr)
-        ::error(ErrorType::ERR_INVALID,
-                "%1%: invalid statement. 'return' statements not allowed in parsers.", statement);
+    if (!findContext<IR::Function>()) {
+        auto inParser = findContext<IR::P4Parser>();
+        if (inParser != nullptr)
+            ::error(ErrorType::ERR_INVALID,
+                    "%1%: invalid statement. 'return' statements not allowed in parsers.",
+                    statement);
+    }
 }
 
 /// Exit statements are not allowed in parsers or functions

ir/expression.def

@@ -243,7 +243,7 @@ class BoolLiteral : Literal {
 class StringLiteral : Literal {
     cstring value;
     validate{ if (value.isNull()) BUG("null StringLiteral"); }
-    toString{ return cstring("\"") + value + "\""; }
+    toString{ return cstring("\"") + value.escapeJson() + "\""; }
     StringLiteral(ID v) : Literal(v.srcInfo), value(v.name) {}
 #emit
     operator IR::ID() const { return IR::ID(srcInfo, value); }

lib/cstring.cpp

@@ -265,3 +265,9 @@ cstring cstring::toUpper() {
     return ret;
 }
 
+cstring cstring::capitalize() {
+    std::string st = str;
+    st[0] = ::toupper(st[0]);
+    cstring ret = cstring::to_cstring(st);
+    return ret;
+}

lib/cstring.h

@@ -260,6 +260,8 @@ class cstring {
 
     // convert the cstring to upper case
     cstring toUpper();
+    // capitalize the first symbol
+    cstring capitalize();
 };
 
 inline bool operator==(const char *a, cstring b) { return b == a; }

test/gtest/cstring.cpp

@@ -50,6 +50,16 @@ TEST(cstring, construct) {
     EXPECT_FALSE(c.isNull());
 }
 
+TEST(cstring, toupper) {
+    cstring c = "simple";
+    cstring c1= "";
+
+    EXPECT_EQ(c.toUpper(), "SIMPLE");
+    EXPECT_EQ(c1.toUpper(), "");
+    EXPECT_EQ(c.capitalize(), "Simple");
+    EXPECT_EQ(c1.capitalize(), "");
+}
+
 TEST(cstring, compare) {
     cstring c = "simple";
     cstring c1 = "";

testdata/p4_16_samples/issue3307.p4

@@ -0,0 +1,15 @@
+typedef bit t;
+extern e {
+  e();
+  abstract t f(in t a);
+}
+parser MyParser(t tt) {
+    e() ee = {
+      t f(in t a) {
+        return a;
+      }
+    };
+    state start {
+        transition accept;
+    }
+}

testdata/p4_16_samples_outputs/issue3307-first.p4

@@ -0,0 +1,17 @@
+typedef bit<1> t;
+extern e {
+    e();
+    abstract t f(in t a);
+}
+
+parser MyParser(t tt) {
+    e() ee = {
+        t f(in t a) {
+            return a;
+        }
+    };
+    state start {
+        transition accept;
+    }
+}
+

testdata/p4_16_samples_outputs/issue3307-frontend.p4

@@ -0,0 +1,6 @@
+typedef bit<1> t;
+extern e {
+    e();
+    abstract t f(in t a);
+}
+

testdata/p4_16_samples_outputs/issue3307.p4

@@ -0,0 +1,17 @@
+typedef bit<1> t;
+extern e {
+    e();
+    abstract t f(in t a);
+}
+
+parser MyParser(t tt) {
+    e() ee = {
+        t f(in t a) {
+            return a;
+        }
+    };
+    state start {
+        transition accept;
+    }
+}
+

testdata/p4_16_samples_outputs/issue3307.p4-stderr

@@ -0,0 +1 @@
+[--Wwarn=missing] warning: Program does not contain a `main' module

testdata/p4_16_samples_outputs/pragma-string-first.p4

@@ -1,6 +1,5 @@
 @name("original") const bit<1> b = 1w1;
-@name("string \" with \" quotes") const bit<1> c = 1w1;
-@name("string with
-newline") const bit<1> d = 1w1;
+@name("string \\\" with \\\" quotes") const bit<1> c = 1w1;
+@name("string with\nnewline") const bit<1> d = 1w1;
 @name("string with quoted newline") const bit<1> e = 1w1;
 @name("8-bit string ⟶") const bit<1> f = 1w1;

testdata/p4_16_samples_outputs/pragma-string.p4

@@ -1,6 +1,5 @@
 @name("original") const bit<1> b = 1;
-@name("string \" with \" quotes") const bit<1> c = 1;
-@name("string with
-newline") const bit<1> d = 1;
+@name("string \\\" with \\\" quotes") const bit<1> c = 1;
+@name("string with\nnewline") const bit<1> d = 1;
 @name("string with quoted newline") const bit<1> e = 1;
 @name("8-bit string ⟶") const bit<1> f = 1;

testdata/p4_16_samples_outputs/specIssue884-first.p4

@@ -34,10 +34,7 @@ struct meta_t {
 control Ingress(inout headers_t hdr, inout meta_t meta) {
     Hash<bit<32>>(algo = HashAlgorithm_t.CRC32) hash1;
     Hash<bit<32>>(poly = CRCPolynomial<bit<16>>(coeff = 16w0x107)) hash2;
-    LCGMatrix<bit<8>, bit<10>>(8w4, 10w7, "1000100
-         0100011
-         0010110
-         0001001") hamming;
+    LCGMatrix<bit<8>, bit<10>>(8w4, 10w7, "1000100\n         0100011\n         0010110\n         0001001") hamming;
     Hash<bit<32>>(matrix = hamming) hash3;
     Hash<bit<32>>(formula = "magic_formula()") hash4;
     apply {

testdata/p4_16_samples_outputs/specIssue884-frontend.p4

@@ -35,10 +35,7 @@ control Ingress(inout headers_t hdr, inout meta_t meta) {
     @name("Ingress.hash1") Hash<bit<32>>(algo = HashAlgorithm_t.CRC32) hash1_0;
     @name("Ingress.tmp") CRCPolynomial<bit<16>>(coeff = 16w0x107) tmp;
     @name("Ingress.hash2") Hash<bit<32>>(poly = tmp) hash2_0;
-    @name("Ingress.hamming") LCGMatrix<bit<8>, bit<10>>(8w4, 10w7, "1000100
-         0100011
-         0010110
-         0001001") hamming_0;
+    @name("Ingress.hamming") LCGMatrix<bit<8>, bit<10>>(8w4, 10w7, "1000100\n         0100011\n         0010110\n         0001001") hamming_0;
     @name("Ingress.hash3") Hash<bit<32>>(matrix = hamming_0) hash3_0;
     @name("Ingress.hash4") Hash<bit<32>>(formula = "magic_formula()") hash4_0;
     apply {

testdata/p4_16_samples_outputs/specIssue884-midend.p4

@@ -35,10 +35,7 @@ control Ingress(inout headers_t hdr, inout meta_t meta) {
     @name("Ingress.hash1") Hash<bit<32>>(algo = HashAlgorithm_t.CRC32) hash1_0;
     @name("Ingress.tmp") CRCPolynomial<bit<16>>(coeff = 16w0x107) tmp;
     @name("Ingress.hash2") Hash<bit<32>>(poly = tmp) hash2_0;
-    @name("Ingress.hamming") LCGMatrix<bit<8>, bit<10>>(8w4, 10w7, "1000100
-         0100011
-         0010110
-         0001001") hamming_0;
+    @name("Ingress.hamming") LCGMatrix<bit<8>, bit<10>>(8w4, 10w7, "1000100\n         0100011\n         0010110\n         0001001") hamming_0;
     @name("Ingress.hash3") Hash<bit<32>>(matrix = hamming_0) hash3_0;
     @name("Ingress.hash4") Hash<bit<32>>(formula = "magic_formula()") hash4_0;
     apply {

testdata/p4_16_samples_outputs/specIssue884.p4

@@ -34,10 +34,7 @@ struct meta_t {
 control Ingress(inout headers_t hdr, inout meta_t meta) {
     Hash<bit<32>>(algo = HashAlgorithm_t.CRC32) hash1;
     Hash<bit<32>>(poly = CRCPolynomial(coeff = 16w0x107)) hash2;
-    LCGMatrix(8w4, 10w7, "1000100
-         0100011
-         0010110
-         0001001") hamming;
+    LCGMatrix(8w4, 10w7, "1000100\n         0100011\n         0010110\n         0001001") hamming;
     Hash<bit<32>>(matrix = hamming) hash3;
     Hash<bit<32>>(formula = "magic_formula()") hash4;
     apply {

testdata/p4_16_samples_outputs/string_anno-first.p4

@@ -1,6 +1,5 @@
 @name("original") const bit<1> b = 1w1;
-@name("string \" with \" quotes") const bit<1> c = 1w1;
-@name("string with
-newline") const bit<1> d = 1w1;
+@name("string \\\" with \\\" quotes") const bit<1> c = 1w1;
+@name("string with\nnewline") const bit<1> d = 1w1;
 @name("string with quoted newline") const bit<1> e = 1w1;
 @name("8-bit string ⟶") const bit<1> f = 1w1;

testdata/p4_16_samples_outputs/string_anno.p4

@@ -1,6 +1,5 @@
 @name("original") const bit<1> b = 1;
-@name("string \" with \" quotes") const bit<1> c = 1;
-@name("string with
-newline") const bit<1> d = 1;
+@name("string \\\" with \\\" quotes") const bit<1> c = 1;
+@name("string with\nnewline") const bit<1> d = 1;
 @name("string with quoted newline") const bit<1> e = 1;
 @name("8-bit string ⟶") const bit<1> f = 1;