Fix typo.

Implement |const| keyword.

Add weak hashtable to manage qual types.

More const preparation: allow type casts to follow qualification.

Preparatory refactoring for const types.

Don't allow declaring void variables.

Re-implement array assignment.

Move PrimitiveType_String to a dedicated string type.

Get string literals working again.

Re-add enum support.

Re-introduce definite return analysis.

Remove duplicate test.

Re-add LIFO stack optimizations.

Add divide-by-zero test.

Add preinc-ref test.

Add postinc-ref test.

Add ref-var test.

Add ref-expr test.

Fix indentation.

Add msvc filters file.

Re-added support for reference arguments.

Re-add line and column information to bytecode.

Re-added parameter support.

Moved another test case.

Re-add postinc support.

Get preinc working again.

More GCC bogosity.

Get load-store assign ops working again.

Fix timeout handling in the test harness.

Fix GCC retardedness.

Added array support back.

Prep for ceval.

Added missing file.

Split ArrayType from Type.

Re-add support for |if|, |continue|, |break|.

Add test for bitops and fix a bug in >>>

Add test for |do|.

Fix test harness name printing.

Added missing tests.

Add |while| and |do-while| support back.

Trigger build.

Trigger a build.

Fix OS X build.

Fix Linux 64-bit build again.

Fix Linux 64-bit build.

Bump version to clobber.

Fix Linux build problems.

Massive SemA/BC refactoring to support better type systems. Read on for more.

The previous compiler had a simple pipeline, best outlined as:
(1) Parsing and name binding -> AST
(2) Storage allocation -> AST
(3) Semantic Analysis (SemA) -> AST
(4) Bytecode Compilation (BC) -> Code

This pipeline, unfortunately, had two problems. First, name binding cannot be performed in one pass if we wish to have multi-file support in the form of modules. Name binding must be two-pass.

Second, because SemA was only capable of annotating AST nodes with a single type, most coercion work had to be duplicated in the BC phase, as coercion was not explicit in the SemA output. This made introducing new type rules extremely difficult, and all but precluded concepts like operator overloading (or overloading at all).

This patch rewrites most of Keima's backend. Of interest are the following changes:
(1) CompileContext has been refactored around future multi-file support.
(2) Parsing no longer performs any name binding.
(3) The grammar for type-and-name has been changed from:
(Label | Identifier)? Identifier
to:
Type? Identifier
where:
Type ::= OldType | NewType
OldType ::= Label
NewType ::= Identifier (. NewType)*


Although we do not implement the full production for Type yet, this
distinction is important. A type identifier is now affixed to the AST
as an Expression (right now, always a NameProxy), so it can fully
participate in name binding.

(4) Immediately after parsing, the AST goes through a NamePopulation phase.
This phase creates Scope objects for every scope which declares a name,
and if those names are declaring types or functions, a Symbol is created
and entered into the scope. Symbols entirely replace the old BoundName
classes.

(5) After NamePopulation comes NameBinding. This phase performs three steps:
(a) Links Scope objects together, to form a tree.
(b) Binds any free name to an existing name in the scope chain.
(c) Creates and registers any Symbols for names which have not yet been
added to the scope (for example, local variables).

In accordance, all "allocation" and "binding" concepts have been removed
from Scopes, which are now lightweight container classes.

(6) SemA now generates bytecode for each statement in the AST. Expression
compilation is performed via a separate mechanism called HIR (High-level
Intermediate Representation). To analyze an expression, SemA will walk
the AST, and produce a HIR object for each node. HIR is typed, and SemA
may insert coercion nodes, or even expand an AST node into multiple HIR
nodes. The result of evaluating an expression in SemA is therefore the
the root of a HIR tree, which SemA then sends to the HIRTranslator, which
performs bytecode generation.

As before, SemA still performs full semantic analysis. However, not it
also produces each function's bytecode.

This split allows us to decompose potentially complex semantics into
a more fine-grained, AST-like structure, which can have very simple
code-generation logic. For example, (1.0 + 5) might look like:

HAdd(HFloat(1.0), HConvert(HInteger(5), <Float>))

As part of this decomposition, many opcodes have been removed. Rather than
using typed jumps, we now expand jumps into longer tests. For example:
jge.f <label>
becomes:
ge.f
cvt.f2b
jt <label>

This simplifies the pipeline, and JITs should be able to melt the added
work away.

HIR is not used at a statement level, and HIR does not have any concept
of control-flow.

(7) The old BytecodeCompiler has been removed, as its work is now split
between SemA and HIRTranslator.


In addition, some minor refactorings have taken place:

(1) Opcodes.tbl no longer hardcodes numbers (aaah).
(2) Type has been split into smaller, typed structs.
(3) BytecodeEmitter no longer relies on Pools or RootScopes.
(4) SemA is now responsible for variable/storage allocation.
(5) Native table are now global, rather than per-module. As such, native
declarations now result in a Native object (which still requires a
CALLNATIVE opcode), which is an index into the global table. Natives
must be bound globally. This is in preparation for module support.
(6) Publics are no longer tracked, but rather registered via a global
callback upon module load. This callback can be set by embedders. This
is in preparation for multi-file support.
(7) The BytecodeEmitter now performs Symbol allocations itself, and it
also generates Code objects itself, which removes a good deal of
complexity.

Finally, a test harness has been added. This harness is a python script which finds *.test files, recursively, in the tests folder. For each file it runs the corresponding .sp. The contents of the .test file must match stdout+stderr.

Implement sizeof operator.

Fix bug where assigning string literals to references would not create copies.

Allow structs to contain arrays.

Allow returning arrays from functions.

Enable dynamic array declarations.

Fix bugs where "new x[x]" or "new x = x" would compile.

Restructure Array so the elements vector can be replaced.

Add support for SP1-style fixed array initializers.

Allow more empty array creation.

Added support for declaring empty-length arrays.

Add support for array reference semantics.

Fix bug in error reporting for array assignment dimension mismatches.