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.
This instruction loads a stack limit from a global variable and compares
it to the stack pointer, trapping if the stack has grown beyond the
limit.
Also add a expand_flags transform group containing legalization patterns
for ISAs with CPU flags.
Fixes#234.
The expansion of a heap_addr instruction depends on the type of heap and
its configuration, so this is handled by custom code.
Add a couple examples of heap access code to the language reference
manual.
The code to compute the address of a global variable depends on the kind
of variable, so custom legalization is required.
- Add a legalizer::globalvar module which exposes an
expand_global_addr() function. This module is likely to grow as we add
more types of global variables.
- Add a ArgumentPurpose::VMContext enumerator. This is used to represent
special 'vmctx' arguments that are used as base pointers for vmctx
globals.
