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Avoid infer_rex() and w() on the same x86 encoding template, resolves #1342

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In cranelift x86 encodings, it seemed unintuitive to specialize Templates with both `infer_rex()`` and `w()`: if `w()` is specified, the REX.W bit must be set so a REX prefix is alway required--no need to infer it. This change forces us to write `rex().w()``--it's more explicit and shows more clearly what cranelift will emit. This change also modifies the tests that expected DynRex recipes.
This commit is contained in:
Andrew Brown
2020-03-31 08:43:17 -07:00
parent a325b62ade
commit d0daef6f60
6 changed files with 18 additions and 17 deletions
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4
cranelift/codegen/meta/src/isa/x86/encodings.rs
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@@ -156,7 +156,7 @@ impl PerCpuModeEncodings {
self.enc64(inst.bind(I32), template.infer_rex());
// I64 on x86_64: REX.W set; REX.RXB determined at runtime from registers.
self.enc64(inst.bind(I64), template.infer_rex().w());
self.enc64(inst.bind(I64), template.rex().w());
}
/// Adds I32/I64 encodings as appropriate for a typed instruction.
@@ -192,7 +192,7 @@ impl PerCpuModeEncodings {
self.enc64(inst.bind(B32), template.infer_rex());
// B64 on x86_64: REX.W set; REX.RXB determined at runtime from registers.
self.enc64(inst.bind(B64), template.infer_rex().w());
self.enc64(inst.bind(B64), template.rex().w());
}
/// Add encodings for `inst.i32` to X86_32.