I changed a little bit of the code, but mainly the tests. Several of the remaining failures are actually real failures, so I need to dig through the rest carefully. A lot are failing because the C++ backend is broken.
Fixes#37. The change itself was very easy, but the main problem was to then go and change everything in GenerateCTest that had been written using A.Int as a test type.
I'm pretty sure this test used to fail and got fixed, but I think the
test was fixed to match the incorrect code rather than the other way
around. What it's testing is the abbreviation of a channel end as an
identically-typed channel end, which (since they're both pointers)
should look something like:
Channel *c;
Channel *d = c;
Instead it was generating "d = &c", which broke cgtest87.
The change made to GenerateC to fix this feels a bit awkward to me --
it's very simple, but it's yet another special case in genVariableAM.
All of the genVariable code could really use reworking (again),
perhaps to use some internal representation of the C expression...
NameType is only really needed in the parser, so this takes it out of
NameDef, meaning that later passes defining names no longer need to
set an arbitrary NameType for them. The parser gets slightly more
complicated (because some productions now have to return a SpecType
and a NameType too), but lots of other code gets simpler.
The code that removed free names was the only thing outside the parser
using NameType, and it now makes a more sensible decision based on the
SpecType. Since unscoped names previously didn't have a SpecType at
all, I've added an Unscoped constructor to it and arranged matters
such that unscoped names now get a proper entry in csNames.
Fixes#61.
This makes it possible to mark a slice as not needing runtime
checking, which is immediately useful for _sizes arrays.
This fixes cgtest03, which was previously failing to compile because
the _sizes array for one of the constants in it contained a runtime
check and thus wasn't itself constant. I've added a testcase file for
the relevant bit of code.
It's redundant, since you can always compute them from the variable, and it
makes the code that deals with actuals rather cleaner.
On the other hand, it slightly complicates some of the tests, because any names
you use in an Actual need to be defined...
This touches an awful lot of code, but cgtest07/17 (arrays and retyping) pass.
This is useful because there are going to be places in the future where we'll
want to represent dimensions that are known at runtime but not at compile time
-- for example, mobile allocations, or dynamically-sized arrays. It simplifies
the code in a number of places.
However, we do now need to be careful that expressions containing variables do
not leak into the State, since they won't be affected by later passes.
Two caveats (marked as FIXMEs in the source):
- Retypes checking in the occam parser is disabled, since the plan is to move
it out to a pass anyway.
- There's some (now very obvious) duplication, particularly in the backend, of
bits of code that construct expressions for the total size of an array
(either in bytes or elements); this should be moved to a couple of helper
functions that everything can use.
This is for two reasons: first, the C++CSP backend still needs them, and
second, the way I'd done the removal wasn't correct; since you can have arrays
of them, abbreviate them, etc., they need to be stripped out by an earlier
pass so that other passes don't try to operate upon them.
Most of this is mechanical: changing function names, and carrying the "wptr"
argument around. I've made the code for computing Expressions from Structureds
a bit more generic too.
The only complex bit is the handling of PAR processes, which I'm not very happy
with at the moment; they used to use the normal C calling convention, but now
you need to pack the arguments into the workspace. I'm handling this at the
moment by generating wrapper functions that do the unpacking, but it would be
better in the future to make the wrapper PROCs that we already generate have
the right interface.
This won't work for programs that use any of the top-level channels yet, since
there are no handlers for them.
