Add a "cfg_postorder:" printout to the "test domtree" file tests and use
that to check the computed CFG post-order instead of doing it manually
with Rust code.
`stack_addr` and unrestricted loads and stores *can* be used with entirely
defined behavior. The sense in which they're not "safe" is only that it's
possible to misuse them. This subtlety wasn't captured in the definition
of "safe" here, so for now, just remove the definition so that it doesn't
cause confusion.
* Clarify undefined behavior and notrap.
Remove the "No undefined behavior" paragraph from the README. The other
paragraphs, specifically "Portable semantics" and
"Fast sandbox verification", describe Cretonne's goals in this area.
Define *addressable* and *accessible* memory, so that trapping remains a fully defined part of the semantics, and we have a clear boundary around undefined behavior, and use these terms to describe related constructs.
Add EBB parameter and EBB argument to the langref glossary to clarify
the distinction between formal EBB parameter values and arguments passed
to branches.
- Replace "ebb_arg" with "ebb_param" in function names that deal with
EBB parameters.
- Rename the ValueDef variants to Result and Param.
- A bunch of other small langref fixes.
No functional changes intended.
Add integer and floating comparison instructions that return CPU flags:
ifcmp, ifcmp_imm, and ffcmp.
Add conditional branch instructions that check CPU flags: brif, brff
Add instructions that check a condition in the CPU flags and return a
b1: trueif, trueff.
These two value types represent the state of CPU flags after an integer
comparison and a floating point comparison respectively.
Instructions using these types TBD.
The value types are now classified into three groups:
1. Lane types are scalar types that can also be used to form vectors.
2. Vector types 2-256 copies of a lane type.
3. Special types. This is where the CPU flag types will go.
The special types can't be used to form vectors.
Change the numbering scheme for value types to make room for the special
types and add `is_lane()` and `is_special()` classification methods.
The VOID type still has number 0, but it can no longer appear as a
vector lane. It classifies as special now.
The word "scalar" is a bit vague and tends to mean "non-vector". Since
we are about to add new CPU flag value types that can't appear as vector
lanes, make the distinction clear: LaneType represents value types that
can appear as a vector lane.
Also replace the Type::is_scalar() method with an is_vector() method.
These are parallels to the existing regmove instruction, but the divert
the value to and from a stack slot.
Like regmove diversions, this is a temporary diversion that must be
local to the EBB.
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.
Add preamble syntax for declaring static and dynamic heaps, and update
the langref section on heaps. Add IR support for heap references.
Remove the heap_load and heap_store as discussed in #144. We will use
heap_addr along with native load and store instructions in their place.
Add the heap_addr instruction and document its bounds checking
semantics.
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.
See #144 for discussion.
- Add a new GlobalVar entity type both in Python and Rust.
- Define a UnaryGlobalVar instruction format containing a GlobalVar
reference.
- Add a globalvar.rs module defining the GlobalVarData with support for
'vmctx' and 'deref' global variable kinds.
Langref:
Add a section about global variables and the global_addr
instruction.
Parser:
Add support for the UnaryGlobalVar instruction format as well as
global variable declarations in the preamble.
Also move the extending loads and truncating stores into the bulkier
"Operations" section to improve the flow of the "Memory" section in the
language reference.
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.
ARM has all of these as scalar integer instructions. Intel has band_not
in SSE and as a scalar in BMI1.
Add the trivial legalization patterns that use a bnot instruction.
Add instructions representing Intel's division instructions which use a
numerator that is twice as wide as the denominator and produce both the
quotient and remainder.
Add encodings for the x86_[su]divmodx instructions.
* Clarify that extended basic blocks are abbreviated as EBB.
* Fix typo.
* Fix a typo.
* Fix typos.
* Use the same phrase to indicate scalar-only as other places in the doc.
* Mention that `band_imm` and friends are scalar-only.
And mention that they're equivalent to their respective
non-immediate-form counterparts.
Add a StackSlotKind enumeration to help keep track of the different
kinds of stack slots supported:
- Incoming and outgoing function arguments on the stack.
- Spill slots and locals.
Change the text format syntax for declaring a stack slot to use a kind
keyword rather than just 'stack_slot'.
* 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
* Skeleton simple_gvn pass.
* Basic testing infrastructure for simple-gvn.
* Add can_load and can_store flags to instructions.
* Move the replace_values function into the DataFlowGraph.
* Make InstructionData derive from Hash, PartialEq, and Eq.
* Make EntityList's hash and eq functions panic.
* Change Ieee32 and Ieee64 to store u32 and u64, respectively.
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.
All values are now references into the value table, so drop the
distinction between direct and table values. Direct values don't exist
any more.
Also remove the parser support for the 'vxNN' syntax. Only 'vNN' values
can be parsed now.
Any *.cton files in the docs directory are now included when running the
test-all.sh script. This is to ensure that the examples are in fact
correct IL.
Always print NaN and Inf floats with a sign. Print the positive ones as
+NaN and +Inf to make them easier to parse.
This instruction behaves like icmp fused with brnz, and it can be used
to represent fused compare+branch instruction on Intel when optimizing
for macro-op fusion.
RISC-V provides compare-and-branch instructions directly, and it is
needed there too.
The meaning of format.typevar_operand changes recently to be relative to
value operands only instead of all operands. The Sphinx cton domain
wasn't updated.
