This allows the assertions to be disabled in release builds, so that
the code is faster and smaller, at the expense of not performing the
checks. Assertions can be re-enabled in release builds with the
debug-assertions flag in Cargo.toml, as the top-level Cargo.toml
file does.
Changes:
* Adds a new generic instruction, SELECTIF, that does value selection (a la
conditional move) similarly to existing SELECT, except that it is
controlled by condition code input and flags-register inputs.
* Adds a new Intel x86_64 variant, 'baseline', that supports SSE2 and
nothing else.
* Adds new Intel x86_64 instructions BSR and BSF.
* Implements generic CLZ, CTZ and POPCOUNT on x86_64 'baseline' targets
using the new BSR, BSF and SELECTIF instructions.
* Implements SELECTIF on x86_64 targets using conditional-moves.
* new test filetests/isa/intel/baseline_clz_ctz_popcount.cton
(for legalization)
* new test filetests/isa/intel/baseline_clz_ctz_popcount_encoding.cton
(for encoding)
* Allow lib/cretonne/meta/gen_legalizer.py to generate non-snake-caseified
Rust without rustc complaining.
Fixes#238.
Also make sure we generate type checks for the controlling type variable
in legalization patterns. This is not needed for encodings since the
encoding tables are already keyed on the controlling type variable.
Not all floating point condition codes are directly supported by the
ucimiss/ucomisd instructions. Some inequalities need to be reversed and
eq+ne require two separate tests.
A cursor now also remembers a current source location which will be
assigned to all new instructions created with the cursor.
The old layout::Cursor can't support source locations because it doesn't
have a reference to the full ir::Function.
The custom_legalize() method on XFormGroup can be used to call a
custom function to legalize specific opcodes.
This will be used shortly to expand global_addr which has an expansion
that depends on the details of the global variable being referenced.
Stop passing Cursor references to legalizer functions. Give them the
whole &mut Function instead. Given the whole Function reference, these
functions can create their own cursors.
This lets legalizer actions access other Function data structures like
the global variables.
* Add Atom and Literal base classes to CDSL Ast. Change substitution() and copy() on Def/Apply/Rtl to support substituting Var->Union[Var, Literal]. Check in Apply() constructor kinds of passed in Literals respect instruction signature
* Change verify_semantics to check all possible instantiations of enumerated immediates (needed to descrive icmp). Add all bitvector comparison primitives and bvite; Change set_semantics to optionally accept XForms; Add semantics for icmp; Fix typing errors in semantics/{smtlib, elaborate, __init__}.py after the change of VarMap->VarAtomMap
* Forgot macros.py
* Nit obscured by testing with mypy enabled present.
* Typo
The Cursor navigation methods all just depend on the cursor's position
and layout reference. Make a CursorBase trait that provides access to
this information with methods and implement the navigation methods on
top of that.
This makes it possible to have multiple types implement the cursor
interface.
The generated legalization code needs to evaluate any instruction
patterns on the input pattern being matched.
Emit predicate checking code inside the InstructionFormat pattern match
where all the instruction's immediate fields are available to the
predicate code.
Also make sure an `args` array is available for any type predicates to
evaluate correctly.
Each input pattern can have a predicate in addition to an opcode being
matched. When an opcode has multiple patterns, execute the first pattern
with a true predicate.
The predicates can be type checks or instruction predicates checking
immediate fields.
Replace the isa::Legalize enumeration with a function pointer. This
allows an ISA to define its own specific legalization actions instead of
relying on the default two.
Generate a LEGALIZE_ACTIONS table for each ISA which contains
legalization function pointers indexed by the legalization codes that
are already in the encoding tables. Include this table in
isa/*/enc_tables.rs.
Give the `Encodings` iterator a reference to the action table and change
its `legalize()` method to return a function pointer instead of an
ISA-specific code.
The Result<> returned from TargetIsa::encode() no longer implements
Debug, so eliminate uses of unwrap and expect on that type.
* Reduce code duplication in TypeConstraint subclasses; Add ConstrainWiderOrEqual to ti and to ireduce,{s,u}extend and f{promote,demote}; Fix bug in emitting constraint edges in TypeEnv.dot(); Modify runtime constraint checks to reject match when they encounter overflow
* Rename Constrain types to something shorter; Move lane_bits/lane_counts in subclasses of ValueType; Add wider_or_eq function in rust and python;
Now that we can detach and reuse all values, there is no longer a need
to create a lot of alias values during pattern expansion. Instead, reuse
the values from the source pattern when emitting instructions in the
destination pattern.
If a destination instruction produces the exact same values as a source
instruction, simply leave the values attached and replace the
instruction it. Otherwise, detach the source values, reuse them in the
expansion, and remove the source instruction afterwards.
Since results are in a value list, they don't need to form a linked
list any longer.
- Simplify make_inst_results() to create values in the natural order.
- Eliminate the last use of next_secondary_value().
- Delete unused result manipulation methods.
Compute an instruction predicate from any constant values given as
arguments for the immediate operands in an instruction pattern.
Allows for patterns like icmp.i32(intcc.ugt, x, y) or iadd_imm.i32(x, 1)
Trap these predicates in the legalizer code generator since we can't
actually handle them yet.
Consolidate the imm_members and imm_kinds into this list so the
FormatField is the single definition of these properties.
This makes it easier to access the precomputed FormatFields
parametrically, avoiding going through getattr().
This is better for type checking too.
Legalizing some instructions may require modifications to the control
flow graph, and some operations need to use the CFG analysis.
The CFG reference is threaded through all the legalization functions to
reach the generated expansion functions as well as the legalizer::split
module where it will be used first.
The legalizer often splits values into parts with the vsplit and
isplit_lohi instructions. Avoid doing that for values that are already
defined by the corresponding concatenation instructions.
This reduces the number of instructions created during legalization, and
it simplifies later optimizations. A number of dead concatenation
instructions are left behind. They can be trivially cleaned up by a dead
code elimination pass.
Instead, just return the first of the detached values, and provide a
next_secondary_result() method for traversing the list.
This is equivalent to how detach_ebb_args() works, and it allows the
data flow graph to be modified while traversing the list of results.
The value_list flag can be inferred from the presence of VARIABLE_ARGS
in the operand list.
The boxed_storage flag is obsolete. We don't need boxed storage anywhere
no that we have value lists instead.
Allow some flexibility in the signature matching for instruction
formats. In particular, look for a value list format as a second chance
option.
The Return, ReturnReg, and TernaryOverflow formats all fit the single
MultiAry catch-all format for instructions without immediate operands.
Make some changes that will make it easier to get rid of the
'value_operands' and 'members' fields in the Python InstructionFormat
class. This is necessary to be able to combine instruction formats that
all use a value list representation, but with different fixed value
operands. The goal is to eventually identify formats by a new signature:
(multiple_results, imm_kinds, num_value_operands)
Start by adding new fields:
- imm_members and imm_kinds are lists describing the format operands,
excluding any values and variable_args operands.
- num_value_operands is the number of fixed value operands, or None in a
has_value-list format.
Use these new members in preference to the old ones where possible.
Use the inferred type variables to construct a type argument for builder
methods. This is for those instructions where the result types cannot be
computed from the result types.
Add an assertion for the value placements that we don't support yet.
1. A primary result in the source pattern becomes a secondary result in
the destination.
2. A secondary result becomes a secondary result, and the destination
instruction is not exactly matching the source.
Since we're deconstructing an instruction anyway, go ahead and resolve
any value aliases on its arguments before we construct the replacement
instructions.
If a secondary value in the source pattern becomes a primary value in
the destination pattern, it is not possible to overwrite the definition
of the source value.
Instead, change the original source value to an alias to the new promary
value.
When expanding iadd_cout, the original instruction is replaced with an
iadd, and an icmp is inserted after the iadd.
Make sure we advance the insertion position after replacing iadd_cout so
the icmp gets inserted *after* iadd.
When an illegal instruction is replaced with other instructions, back up
and revisit the expanded instructions. The new instructions need to have
encodings assigned too.
This also allows for expansions to contain illegal instructions that
need to be legalized themselves.
Begin emitting legalization patterns in the form of two functions,
'expand' and 'narrow' that are included in legalizer.rs.
The generated code compiles, but it is not fully working yet. We need to
deal with the special cases of instructions producing multiple results.
There's 4 classes of variables, depending on whether they have defs in
the source and destination patterns.
Add more XForm verification: In a legalize XForm, all source defs must
be outputs.
Fix a legalize pattern bug caught by this.
This is a work in progress. The 'legalizer.rs' file generated by
gen_legalizer.py is not used for anything yet.
Add PEP 484 type annotations to a bunch of Python code.
