Add a calling-convention setting to the `Flags` used as part of the
`TargetIsa`. This allows Cretonne code that generates calls to use the
correct convention, such as when emitting libcalls during legalization
or when the wasm frontend is decoding functions. This setting can be
overridden per-function.
This also adds "fast", "cold", and "fastcall" conventions, with "fast"
as the new default. Note that "fast" and "cold" are not intended to be
ABI-compatible across Cretonne versions.
This will also ensure Windows users will get an `unimplemented!` rather
than silent calling-convention mismatches, which reflects the fact that
Windows calling conventions are not yet implemented.
This also renames SpiderWASM, which isn't camel-case, to Baldrdash,
which is, and which is also a more relevant name.
This adds a "colocated" flag to function and symbolic global variables which
indicates that they are defined along with the current function, so they can
use PC-relative addressing.
This also changes the function decl syntax; the name now always precedes the
signature, and the "function" keyword is no longer included.
To keep cross-compiling straightforward, Cretonne shouldn't have any
behavior that depends on the host. This renames the "Native" calling
convention to "SystemV", which has a defined meaning for each target,
so that it's clear that the calling convention doesn't change
depending on what host Cretonne is running on.
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.
