Sections not merged

[jorgensd]

Consider the following MWE:

import ufl
import basix.ufl

c_el = basix.ufl.element("Lagrange", "triangle", 1, shape=(2, ))
mesh = ufl.Mesh(c_el)

el = basix.ufl.element("Lagrange", "triangle", 2)

V = ufl.FunctionSpace(mesh, el)

u, v = ufl.TrialFunction(V), ufl.TestFunction(V)
a = ufl.inner(u, v) * ufl.dx

forms = [a]

which generates

// ------------------------ 
// Section: Jacobian
// Inputs: coordinate_dofs, FE1_C0_D10_Q39d
// Outputs: J_c0
double J_c0 = 0.0;
{
  for (int ic = 0; ic < 3; ++ic)
  {
    J_c0 += coordinate_dofs[(ic) * 3] * FE1_C0_D10_Q39d[0][0][0][ic];
  }
}
// ------------------------ 
// ------------------------ 
// Section: Jacobian
// Inputs: coordinate_dofs, FE1_C1_D01_Q39d
// Outputs: J_c3
double J_c3 = 0.0;
{
  for (int ic = 0; ic < 3; ++ic)
  {
    J_c3 += coordinate_dofs[(ic) * 3 + 1] * FE1_C1_D01_Q39d[0][0][0][ic];
  }
}
// ------------------------ 
// ------------------------ 
// Section: Jacobian
// Inputs: coordinate_dofs, FE1_C1_D01_Q39d
// Outputs: J_c1
double J_c1 = 0.0;
{
  for (int ic = 0; ic < 3; ++ic)
  {
    J_c1 += coordinate_dofs[(ic) * 3] * FE1_C1_D01_Q39d[0][0][0][ic];
  }
}
// ------------------------ 
// ------------------------ 
// Section: Jacobian
// Inputs: coordinate_dofs, FE1_C0_D10_Q39d
// Outputs: J_c2
double J_c2 = 0.0;
{
  for (int ic = 0; ic < 3; ++ic)
  {
    J_c2 += coordinate_dofs[(ic) * 3 + 1] * FE1_C0_D10_Q39d[0][0][0][ic];
  }
}

Some of these loops should probably be merged (even if then get unrolled by the compiler).

[jorgensd]

I guess the issue is that the scopes are not optimized for constant prepart sections.