This change is a pure refactoring--no change to functionality. It removes `use crate::ir::types::*` imports and uses instead `types::I32`, e.g., throughout the x64 code. Though it increases code verbosity, this change makes it more clear where the type identifiers come from (they are generated by `cranelif-codegen-meta` so without a prefix it is difficult to find their origin), avoids IDE confusion (e.g. CLion flags the un-prefixed identifiers as errors), and avoids importing unwanted identifiers into the namespace.
This change is a pure refactoring--no change to functionality. It removes newlines between the `use ...` statements in the x64 backend so that rustfmt can format them according to its convention. I noticed some files had followed a manual convention but subsequent additions did not seem to fit; this change fixes that and lightly coalesces some of the occurrences of `use a::b; use a::c;` into `use::{b, c}`.
In the Baldrdash (SpiderMonkey) embedding, we must take care to
zero-extend all function arguments to callees in integer registers when
the types are narrower than 64 bits. This is because, unlike the native
SysV ABI, the Baldrdash ABI expects high bits to be cleared. Not doing
so leads to difficult-to-trace errors where high bits falsely tag an
int32 as e.g. an object pointer, leading to potential security issues.
The jump table offset that's loaded out of the jump table could be
signed (if it's an offset to before the jump table itself), so we should
use a signed extension there, not an unsigned extension.
Using an input register that doesn't belong to the ABCD family (al,
etc.) as the source of movsx/movzx requires a redundant REX prefix, that
was not emitted.
We have to emit both checks against the parity bit (for unordered) and
non-equality bit (for equality), otherwise this returns false when
comparing NaN against itself.
This is tricky: the control flow implicitly implied by the operand makes
it so that the output register may be undefined, if we mark it only as a
"def". Make it a "mod" instead, which matches our usage in the codebase,
and will make it crash if the output operand isn't unconditionally
defined before the instruction.
