Method replace_lane_op

winch/codegen/src/codegen/context.rs:593–626

Prepares arguments for emitting a replace lane operation.

(
        &mut self,
        masm: &mut M,
        kind: ReplaceLaneKind,
        emit: F,
    )

    /// Prepares arguments for emitting a replace lane operation.
    pub fn replace_lane_op<F, M>(
        &mut self,
        masm: &mut M,
        kind: ReplaceLaneKind,
        emit: F,
    ) -> Result<()>
    where
        F: FnOnce(&mut M, RegImm, WritableReg, ReplaceLaneKind) -> Result<()>,
        M: MacroAssembler,
    {
        let src = match kind {
            ReplaceLaneKind::I8x16 | ReplaceLaneKind::I16x8 | ReplaceLaneKind::I32x4 => {
                self.pop_i32_const().map(RegImm::i32)
            }
            ReplaceLaneKind::I64x2 => self.pop_i64_const().map(RegImm::i64),
            ReplaceLaneKind::F32x4 => self.pop_f32_const().map(|v| RegImm::f32(v.bits())),
            ReplaceLaneKind::F64x2 => self.pop_f64_const().map(|v| RegImm::f64(v.bits())),
        }
        .map_or_else(
            || Ok(RegImm::reg(self.pop_to_reg(masm, None)?.into())),
            Ok::<_, crate::Error>,
        )?;

        let dst = self.pop_to_reg(masm, None)?;

        emit(masm, src, writable!(dst.into()), kind)?;

        if let RegImm::Reg(reg) = src {
            self.free_reg(reg);
        }
        self.stack.push(dst.into());

        Ok(())
    }

    /// Drops the last `n` elements of the stack, calling the provided
    /// function for each `n` stack value.