Some REX-less encodings require an ABCD input because they are looking
at 8-bit registers. This constraint doesn't apply with a REX prefix
where the low 8 bits of all registers are addressable.
It can happen that the currently live registers are blocking a smaller
register class completely, so the only way of solving the allocation
problem is to turn some of the live-through registers into solver
variables.
When the quick_solve attempt fails, try to free up registers in the
critical register class by turning live-through values into solver
variables.
The brz and brnz instructions get support for 32-bit jump displacements
for long range branches.
Also change the way branch ranges are specified on tail recipes for the
Intel instructions. All branch displacements are relative to the end of
the instruction, so just compute the branch range origin as the
instruction size instead of trying to specify it in the tail recipe
definitions.
When the return value from a call has been spilled, the reload pass
needs to insert a spill instruction right after the call instruction
which returns its results in registers.
The x86_divmodx traps on integer overflow, but the srem instruction is
not supposed to trap with a -1 divisor.
Generate a legalization expansion for srem that special-cases the -1
divisor to simply return 0.
The extend and reduce instructions have additional type constraints.
Stop inserting sextend instructions after ctz, clz, and popcnt when
translating from WebAssembly. The Cretonne instructions have the same
signature as the WebAssembly equivalents.
An f64 can represent multiple values in the range INT_MIN-1 < x <=
INT_MIN which all truncate to INT_MIN, so comparing the input value
against INT_MIN is not good enough.
Instead, detect overflow on x <= INT_MIN-1 when INT_MIN-1 is an exact
floating point value.
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.
The cton-util executable is used in --release mode to run the file
tests. We want assertions enabled for that.
This doesn't affect the compiler flags used to build the Cretonne crate
when it is used as a dependency in another project.
In 32-bit mode, all function arguments are passed on the stack, not in
registers.
This ABI support is not complete or properly tested, but at least it
doesn't try to pass arguments in r8.
The native x86_fmin and x86_fmax instructions don't behave correctly for
NaN inputs and when comparing +0.0 to -0.0, so we need separate branches
for those cases.
These Intel-specific instructions represent the semantics of the minss /
maxss Intel instructions which behave more like a C ternary operator
than the WebAssembly fmin and fmax instructions.
They will be used as building blocks for implementing the WebAssembly
semantics.
This is used to represent the non-trapping semantics of the cvttss2si and
cvttsd2si instructions (and their vectorized counterparts).
The overflow behavior of this instruction is specific to the Intel ISAs.
There is no float-to-i64 instruction on the 32-bit Intel ISA.
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.
These sign bit manipulations need to use a -0.0 floating point constant
which we didn't have a way of materializing previously.
Add a ieee32.bits(0x...) syntax to the Python AST nodes that creates am
f32 immediate value with the exact requested bitwise representation.
To begin with, these are catch-all encodings with a SIB byte and a
32-bit displacement, so they can access any stack slot via both the
stack pointer and the frame pointer.
In the future, we will add encodings for 8-bit displacements as well as
EBP-relative references without a SIB byte.
This contains encoding details for a stack reference: The base register
and offset to use in the specific instruction encoding.
Generate StackRef objects called in_stk0 etc for the binemit recipe
code. All binemit recipes need to compute base pointer offsets for stack
references, so have the automatically generated code do it.
