diff options
| -rw-r--r-- | sim/README-HACKING | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/sim/README-HACKING b/sim/README-HACKING index cc11d79..21c34f6 100644 --- a/sim/README-HACKING +++ b/sim/README-HACKING @@ -1,11 +1,13 @@ This is a loose collection of notes for people hacking on simulators. -If this document gets big enough it can be prettied it up then. +If this document gets big enough it can be prettied up then. Contents - The "common" directory - Common Makefile Support +- TAGS support - Generating "configure" files +- tconfig.in The "common" directory ====================== @@ -70,9 +72,13 @@ The Makefile.in of a simulator using the common framework should look like: # These variables are given default values in COMMON_PRE_CONFIG_FRAG. # We override the ones we need to here. # Not all of these need to be mentioned, only the necessary ones. +# In fact it is better to *not* mention ones if the value is the default. # List of object files, less common parts. SIM_OBJS = +# List of extra dependencies. +# Generally this consists of simulator specific files included by sim-main.h. +SIM_EXTRA_DEPS = # List of flags to always pass to $(CC). SIM_EXTRA_CFLAGS = # List of extra libraries to link with. @@ -101,6 +107,22 @@ The resulting Makefile is created by doing autoconf substitions on both the target's Makefile.in and Make-common.in, and inserting the two pieces of Make-common.in into the target's Makefile.in at COMMON_{PRE,POST}_CONFIG_FRAG. + +Note that SIM_EXTRA_{INSTALL,CLEAN} could be removed and "::" targets +could be used instead. However, it's not clear yet whether "::" targets +are portable enough. + +TAGS support +============ + +Many files generate program symbols at compile time. +Such symbols can't be found with grep nor do they normally appear in +the TAGS file. To get around this, source files can add the comment + +/* TAGS: foo1 foo2 */ + +where foo1, foo2 are program symbols. Symbols found in such comments +are greppable and appear in the TAGS file. Generating "configure" files ============================ @@ -130,4 +152,13 @@ updated using the sequence: $ make -f Makefile.in autoheader-changelog $ more */new-ChangeLog $ make -f Makefile.in autoheader-install - + +tconfig.in +========== + +File tconfig.in defines one or more target configuration macros +(e.g. a tm.h file). There are very few that need defining. +For a list of all of them, see common/tconfig.in. +It contains them all, commented out. +The intent is that a new port can just copy this file and +define the ones it needs. |