CMakeLists.txt: fix misleading logical_target_for_zephyr_elf comment

The comment for:

  set_target_properties(${logical_target_for_zephyr_elf} PROPERTIES
     OUTPUT_NAME ${KERNEL_NAME})

was completely off-topic and making something relatively simple
incredibly puzzling and time-consuming to understand.

Re-order the if(GKSF OR GKOF) clauses so the two initializations of
logical_target_for_zephyr_elf are close to each other and so the very
short clause is not buried at the bottom of the long one.

Other minor logical_target_for_zephyr_elf comment fixes.

Signed-off-by: Marc Herbert <[email protected]>

Author: marc-hb

CMakeLists.txt

@@ -1298,7 +1298,12 @@ set_property(TARGET   ${ZEPHYR_PREBUILT_EXECUTABLE} PROPERTY LINK_DEPENDS ${PROJ
 add_dependencies(     ${ZEPHYR_PREBUILT_EXECUTABLE} ${ALIGN_SIZING_DEP} ${PRIV_STACK_DEP} ${LINKER_SCRIPT_TARGET} ${OFFSETS_LIB})
 
 
-if(GKOF OR GKSF)
+set(generated_kernel_files ${GKSF} ${GKOF})
+if(NOT generated_kernel_files)
+  # Use the prebuilt elf as the final elf since we don't have a
+  # generation stage.
+  set(logical_target_for_zephyr_elf ${ZEPHYR_PREBUILT_EXECUTABLE})
+else()
   set(KERNEL_ELF kernel_elf)
   set(logical_target_for_zephyr_elf ${KERNEL_ELF})
 
@@ -1334,18 +1339,16 @@ if(GKOF OR GKSF)
   target_link_libraries(${KERNEL_ELF} ${GKOF} ${TOPT} ${PROJECT_BINARY_DIR}/linker_pass_final.cmd ${zephyr_lnk} ${CODE_RELOCATION_DEP})
   set_property(TARGET   ${KERNEL_ELF} PROPERTY LINK_DEPENDS ${PROJECT_BINARY_DIR}/linker_pass_final.cmd)
   add_dependencies(     ${KERNEL_ELF} ${ALIGN_SIZING_DEP} ${PRIV_STACK_DEP} ${LINKER_PASS_FINAL_SCRIPT_TARGET})
-else()
-  set(logical_target_for_zephyr_elf ${ZEPHYR_PREBUILT_EXECUTABLE})
-  # Use the prebuilt elf as the final elf since we don't have a
-  # generation stage.
 endif()
 
 # Export the variable to the application's scope to allow the
 # application to know what the name of the final elf target is.
 set(logical_target_for_zephyr_elf ${logical_target_for_zephyr_elf} PARENT_SCOPE)
 
-# To avoid having the same logical target name for the zephyr lib and
-# the zephyr elf, we set the kernel_elf file name to zephyr.elf.
+# Override the base name of final .elf so:
+# 1. it doesn't depend on the number of passes above and the
+#    post_build_commands below can always find it no matter which is it;
+# 2. it can be defined in Kconfig
 set_target_properties(${logical_target_for_zephyr_elf} PROPERTIES OUTPUT_NAME ${KERNEL_NAME})
 
 set(post_build_commands "")
@@ -1412,11 +1415,14 @@ list(APPEND
   ${extra_post_build_commands}
   )
 
+# Add post_build_commands to post-process the final .elf file produced by
+# either the ZEPHYR_PREBUILT_EXECUTABLE or the KERNEL_ELF executable
+# targets above.
 add_custom_command(
   TARGET ${logical_target_for_zephyr_elf}
   POST_BUILD
   ${post_build_commands}
-  COMMENT "Generating files from zephyr.elf for board: ${BOARD}"
+  COMMENT "Generating files from ${KERNEL_ELF_NAME} for board: ${BOARD}"
   # NB: COMMENT only works for some CMake-Generators
   )