assignShiftSat

fn assignShiftSat(gz: *GenZir, scope: *Scope, infix_node: Ast.Node.Index) InnerError!void {
    try emitDbgNode(gz, infix_node);
    const astgen = gz.astgen;
    const tree = astgen.tree;

    const lhs_node, const rhs_node = tree.nodeData(infix_node).node_and_node;
    const lhs_ptr = try lvalExpr(gz, scope, lhs_node);
    const lhs = try gz.addUnNode(.load, lhs_ptr, infix_node);
    // Saturating shift-left allows any integer type for both the LHS and RHS.
    const rhs = try expr(gz, scope, .{ .rl = .none }, rhs_node);

    const result = try gz.addPlNode(.shl_sat, infix_node, Zir.Inst.Bin{
        .lhs = lhs,
        .rhs = rhs,
    });
    _ = try gz.addPlNode(.store_node, infix_node, Zir.Inst.Bin{
        .lhs = lhs_ptr,
        .rhs = result,
    });
}