Invoking register's read() method compiles, but bmv2 fails to parse JSON

[vikramnathan]

In the attached p4 file, I'm invoking the register read function declared at v1model.p4:74 as follows:

register<bit<128>>(32w1024) keys;
apply {
    bit<128> k = 0;
    keys.read(k, 32w1);
}

This compiles using the p4-bm2-ss binary but fails when run on the simple switch target:

$ sudo ../behavioral-model/targets/simple_switch/simple_switch test.json
Thrift port was not specified, will use 9090
Calling target program-options parser
terminate called after throwing an instance of 'std::runtime_error'
  what():  in Json::Value::operator[](char const*)const: requires objectValue

I've also attached test.json for reference.

However, when I comment out keys.read(k, 32w1) or use keys.write(32k1, k) instead, simple_switch appears to be able to parse the JSON, getting as far as starting its thrift server.

Is this because theread capability is not supported in the behavioral model?

test.json.txt
test.p4.txt

[anirudhSK]

#145 may be a symptom of the same problem: some extern methods from v1model.p4 aren't supported by bmv2, even though they compile fine. There's a hash function call in #145, reproduced below:

hash(meta.hash.hash,
         HashAlgorithm.crc16,
         (bit<16>)0, 
         { meta.ipv4.lkp_ipv4_sa },
         (bit<32>)65536);

Both hash (https://github.com/p4lang/p4c/blob/master/p4include/v1model.p4#L99) and register.read() (https://github.com/p4lang/p4c/blob/master/p4include/v1model.p4#L74) are extern methods declared in v1model.p4

[vikramnathan]

It appears that this is fixed by a more recent commit (our guess is c3bdd1f).