With the change to the parser to preserve indices, it now inserts
placeholders to pad out index spaces as needed. Placeholder functions
use reserved signature indices, so skip them when writing them out,
to avoid writing them out as "sig4294967295".
This makes it easier to debug testcases:
- the entity numbers in a .cton file match the entity numbers used
within Cretonne.
- serializing and deserializing doesn't cause indices to change.
One disadvantage is that if a .cton file uses sparse entity numbers,
deserializing to the in-memory form doesn't compact it. However, the
text format is not intended to be performance-critical, so this isn't
expected to be a big burden.
A CallConv enum on every function signature makes it possible to
generate calls to functions with different calling conventions within
the same ISA / within a single function.
The calling conventions also serve as a way of customizing Cretonne's
behavior when embedded inside a VM. As an example, the SpiderWASM
calling convention is used to compile WebAssembly functions that run
inside the SpiderMonkey virtual machine.
All function signatures must have a calling convention at the end, so
this changes the textual IL syntax.
Before:
sig1 = signature(i32, f64) -> f64
After
sig1 = (i32, f64) -> f64 native
sig2 = (i32) spiderwasm
When printing functions, the signature goes after the return types:
function %r1() -> i32, f32 spiderwasm {
ebb1:
...
}
In the parser, this calling convention is optional and defaults to
"native". This is mostly to avoid updating all the existing test cases
under filetests/. When printing a function, the calling convention is
always included, including for "native" functions.
* Function names should start with %
* Create FunctionName from string
* Implement displaying of FunctionName as %nnnn with fallback to #xxxx
* Run rustfmt and fix FunctionName::with_string in parser
* Implement FunctionName::new as a generic function
* Binary function names should start with #
* Implement NameRepr for function name
* Fix examples in docs to reflect that function names start with %
* Rebase and fix filecheck tests
Enumerate a set of special purposes for function arguments that general
purpose code needs to know about. Some of these argument purposes will
only appear in the signature of the current function, representing
things the prologue and epilogues need to know about like the link
register and callee-saved registers.
Get rid of the 'inreg' argument flag. Arguments can be pre-assigned to a
specific register instead.
Create a new directory hierarchy under 'filetests' for all the tests
that are run by 'cton-util test'.
Convert the parser tests under 'tests/parser' to use 'test cat' and
filecheck directives.
