Because of how name builders used to lazy gather namespaces on the first
requested name, the objects were self mutating. As such only non-const
references could be used to pass them around.
Since that is no longer the case, this restores most of lost const
qualifiers.
This commit moves stuff around to enforce complete information being
present by the time the "Internal" assembly output is ready.
Because of that, the "Internal" format needed to change, now it uses
tag representation close to PTML as opposed to the one close to LLVM's
used before now.
This commit introduces `BasicBlockID` as the unique identifier for a
`efa::BasicBlock` into the CFG. A `BasicBlockID` is defined by a
`MetaAddress` plus an incremental integer. This enables us to have
multiple instances of the same block in a single function, which is
particularly useful when inlining multiple times the same function.
Apart from this, the commit also does the following:
* It drops representing `MetaAddress`es a `structs` in the IR. This created
several issues related to ABI. We now represent them as strings.
* It defines more functions in `support.h`, instead of defining prototypes
by hand in `CodeGenerator.cpp` and the like. Specifically, `unknownPC`
and `raise_exception_helper`. We also introduce a C "constructor" for
`PlainMetaAddress`.
* It significantly reduces the API of `GeneratedCodeBasicInfo`, which
was supposed to be put on a diet since a long time. Specifically,
many jump target related methods have been moved to free functions in
`IRHelpers.h`. Also `GCBI::getSuccessors` has been pushed into its
only user, `PruneRetSuccessors`, to prevent further usage of a
deprecated API. In the future, it would be nice to drop it entirely.
* It introduces `efa::BasicBlock::InlinedFrom`.
* Introduce an enum to represent named argument indices for `newpc`.
This enables us to more effectively manipulate its argument list.
* It improves the verification and error reporting for
`efa::FunctionMetadata`.
* Update tests.
This commit is preliminary to another piece of work to improve the
generality of inlining beyond the simple "fake function" scenario, for
which the feature was originally conceived.
This change introduces some duplication but ensures an important
property of `tuple_tree_generate`d: data structures: all the leaves are
scalars. Previously, yield::Function was using efa::BasicBlock, making
things more difficult under certain conditions.
Specifically, we can rely on the fact that, when generating a visit to
the TupleTree, we know everything about all non-scalars.
Alessandro Di Federico