MSP430: Add new methods of finding external MCU data file

MCU data file can now be specified with an environment variable or installed
into a toolchain subdirectory.

2019-11-04  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

gcc/
	* config/msp430/driver-msp430.c
	(msp430_get_linker_devices_include_path): New spec function.
	* config/msp430/msp430-devices.c (msp430_dirname): New function.
	(extract_devices_dir_from_exec_prefix): New function.
	(extract_devices_dir_from_collect_gcc): New function.
	(msp430_check_env_var_for_devices): New function.
	(msp430_check_path_for_devices): Use xstrdup instead of ASTRDUP.
	(parse_devices_csv): Call msp430_check_env_var_for_devices if
	devices.csv was not found using other methods.
	* config/msp430/msp430-devices.h (msp430_check_env_var_for_devices):
	New prototype.
	(msp430_dirname): Likewise.
	* config/msp430/msp430.c (msp430_register_pre_includes): New function.
	* config/msp430/msp430.h (EXTRA_SPEC_FUNCTIONS): Add
	msp430_get_linker_devices_include_path.
	(TARGET_EXTRA_PRE_INCLUDES): Define.
	* doc/invoke.texi: Document new ways of searching for support files.

gcc/testsuite/
	* gcc.target/msp430/devices/csv-using-env-var.c: New test.
	* gcc.target/msp430/devices/csv-using-installed.c: New test.
	* gcc.target/msp430/devices/csv-using-option.c: New test.
	* gcc.target/msp430/devices/devices-main.c: New test source file.
	* gcc.target/msp430/devices/msp430-devices.h: New test.
	* gcc.target/msp430/msp430.exp (msp430_device_permutations_runtest):
	Add special cases for csv-using* tests.
	Define TESTING_HARD_DATA when running tests that use hard-coded device
	data.
	(get_installed_device_data_path): New.
	(msp430_hide_installed_devices_data): New.
	(msp430_restore_installed_devices_data): New.
	(msp430_test_installed_device_data): New.
	(msp430_install_device_data): New.

From-SVN: r277772

1 files changed, 27 insertions, 2 deletions

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index faa7fa9..122a23e 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -23231,8 +23231,33 @@ The ISA and hardware multiply supported for the different MCUs is hard-coded
 into GCC.  However, an external @samp{devices.csv} file can be used to
 extend device support beyond those that have been hard-coded.
 
-GCC searches for the @samp{devices.csv} file on the paths specified
-with the @code{-I} and @code{-L} options.
+GCC searches for the @samp{devices.csv} file using the following methods in the
+given precedence order, where the first method takes precendence over the
+second which takes precedence over the third.
+
+@table @asis
+@item Include path specified with @code{-I} and @code{-L}
+@samp{devices.csv} will be searched for in each of the directories specified by
+include paths and linker library search paths.
+@item Path specified by the environment variable @samp{MSP430_GCC_INCLUDE_DIR}
+Define the value of the global environment variable
+@samp{MSP430_GCC_INCLUDE_DIR}
+to the full path to the directory containing devices.csv, and GCC will search
+this directory for devices.csv.  If devices.csv is found, this directory will
+also be registered as an include path, and linker library path.  Header files
+and linker scripts in this directory can therefore be used without manually
+specifying @code{-I} and @code{-L} on the command line.
+@item The @samp{msp430-elf/include/devices} directory
+Finally, GCC will examine @samp{msp430-elf/include/devices} from the
+toolchain root directory.  This directory does not exist in a default
+installation, but if the user has created it and copied @samp{devices.csv}
+there, then the MCU data will be read.  As above, this directory will
+also be registered as an include path, and linker library path.
+
+@end table
+If none of the above search methods find @samp{devices.csv}, then the
+hard-coded MCU data is used.
+
 
 @item -mwarn-mcu
 @itemx -mno-warn-mcu