gimple
     |    layout: GSS_BASE
     |    used for 4 codes: GIMPLE_ERROR_MARK
     |                      GIMPLE_NOP
     |                      GIMPLE_OMP_SECTIONS_SWITCH
     |                      GIMPLE_PREDICT
     |
     + gimple_statement_with_ops_base
     |   |    (no GSS layout)
     |   |
     |   + gimple_statement_with_ops
     |   |   |    layout: GSS_WITH_OPS
     |   |   |
     |   |   + gcond
     |   |   |     code: GIMPLE_COND
     |   |   |
     |   |   + gdebug
     |   |   |     code: GIMPLE_DEBUG
     |   |   |
     |   |   + ggoto
     |   |   |     code: GIMPLE_GOTO
     |   |   |
     |   |   + glabel
     |   |   |     code: GIMPLE_LABEL
     |   |   |
     |   |   + gswitch
     |   |         code: GIMPLE_SWITCH
     |   |
     |   + gimple_statement_with_memory_ops_base
     |       |    layout: GSS_WITH_MEM_OPS_BASE
     |       |
     |       + gimple_statement_with_memory_ops
     |       |   |    layout: GSS_WITH_MEM_OPS
     |       |   |
     |       |   + gassign
     |       |   |    code GIMPLE_ASSIGN
     |       |   |
     |       |   + greturn
     |       |        code GIMPLE_RETURN
     |       |
     |       + gcall
     |       |        layout: GSS_CALL, code: GIMPLE_CALL
     |       |
     |       + gasm
     |       |        layout: GSS_ASM, code: GIMPLE_ASM
     |       |
     |       + gtransaction
     |                layout: GSS_TRANSACTION, code: GIMPLE_TRANSACTION
     |
     + gimple_statement_omp
     |   |    layout: GSS_OMP.  Used for code GIMPLE_OMP_SECTION
     |   |
     |   + gomp_critical
     |   |        layout: GSS_OMP_CRITICAL, code: GIMPLE_OMP_CRITICAL
     |   |
     |   + gomp_for
     |   |        layout: GSS_OMP_FOR, code: GIMPLE_OMP_FOR
     |   |
     |   + gomp_parallel_layout
     |   |   |    layout: GSS_OMP_PARALLEL_LAYOUT
     |   |   |
     |   |   + gimple_statement_omp_taskreg
     |   |   |   |
     |   |   |   + gomp_parallel
     |   |   |   |        code: GIMPLE_OMP_PARALLEL
     |   |   |   |
     |   |   |   + gomp_task
     |   |   |            code: GIMPLE_OMP_TASK
     |   |   |
     |   |   + gimple_statement_omp_target
     |   |            code: GIMPLE_OMP_TARGET
     |   |
     |   + gomp_sections
     |   |        layout: GSS_OMP_SECTIONS, code: GIMPLE_OMP_SECTIONS
     |   |
     |   + gimple_statement_omp_single_layout
     |       |    layout: GSS_OMP_SINGLE_LAYOUT
     |       |
     |       + gomp_single
     |       |        code: GIMPLE_OMP_SINGLE
     |       |
     |       + gomp_teams
     |                code: GIMPLE_OMP_TEAMS
     |
     + gbind
     |        layout: GSS_BIND, code: GIMPLE_BIND
     |
     + gcatch
     |        layout: GSS_CATCH, code: GIMPLE_CATCH
     |
     + geh_filter
     |        layout: GSS_EH_FILTER, code: GIMPLE_EH_FILTER
     |
     + geh_else
     |        layout: GSS_EH_ELSE, code: GIMPLE_EH_ELSE
     |
     + geh_mnt
     |        layout: GSS_EH_MNT, code: GIMPLE_EH_MUST_NOT_THROW
     |
     + gphi
     |        layout: GSS_PHI, code: GIMPLE_PHI
     |
     + gimple_statement_eh_ctrl
     |   |    layout: GSS_EH_CTRL
     |   |
     |   + gresx
     |   |        code: GIMPLE_RESX
     |   |
     |   + geh_dispatch
     |            code: GIMPLE_EH_DISPATCH
     |
     + gtry
     |        layout: GSS_TRY, code: GIMPLE_TRY
     |
     + gimple_statement_wce
     |        layout: GSS_WCE, code: GIMPLE_WITH_CLEANUP_EXPR
     |
     + gomp_continue
     |        layout: GSS_OMP_CONTINUE, code: GIMPLE_OMP_CONTINUE
     |
     + gomp_atomic_load
     |        layout: GSS_OMP_ATOMIC_LOAD, code: GIMPLE_OMP_ATOMIC_LOAD
     |
     + gimple_statement_omp_atomic_store_layout
         |    layout: GSS_OMP_ATOMIC_STORE_LAYOUT,
         |    code: GIMPLE_OMP_ATOMIC_STORE
         |
         + gomp_atomic_store
         |        code: GIMPLE_OMP_ATOMIC_STORE
         |
         + gomp_return
                  code: GIMPLE_OMP_RETURN