  When scale symmetry is implemented into hidden local symmetry in low-energy
strong interactions to arrive at a scale-invariant hidden local symmetric (HLS)
theory, the scalar $f_0(500)$ may be interpreted as pseudo-Nambu-Goldstone
(pNG) boson, i.e., dilaton, of spontaneously broken scale invariance, joining
the pseudo-scalar pNG bosons $\pi$ and the matter fields $V=(\rho,\omega)$ as
relevant degrees of freedom. Implementing the skyrmion-half-skyrmion transition
predicted at large $N_c$ in QCD at a density roughly twice the nuclear matter
density found in the crystal simulation of dense skyrmion matter, we determine
the intrinsically density-dependent (IDD) "bare parameters" of the
scale-invariant HLS Lagrangian matched to QCD at a matching scale $\Lambda_M$.
The resulting effective Lagrangian, with the parameters scaling with the
density of the system, is applied to nuclear matter and dense baryonic matter
relevant to massive compact stars by means of the double-decimation
renormalization-group $V_{lowk}$ formalism. We satisfactorily post-dict the
properties of normal nuclear matter and more significantly {\it predict} the
EoS of dense compact-star matter that quantitatively accounts for the presently
available data coming from both the terrestrial and space laboratories. We
interpret the resulting structure of compact-star matter as revealing how the
combination of hidden-scale symmetry and hidden local symmetry manifests itself
in compressed baryonic matter.
