Support for 64-bit location_t: Activate 64-bit location_t

Change location_t to be a 64-bit integer instead of a 32-bit integer in
libcpp.

Also included in this change are the two other patches in the original
series which depended on this one; I am committing them all at once in case
it needs to be reverted later:

-Support for 64-bit location_t: gimple parts

The size of struct gimple increased by 8 bytes with the change in size of
location_t from 32- to 64-bit; adjust the WORD markings in the comments
accordingly. It seems that most of the WORD markings were off by one already,
probably not having been updated after a previous reduction in the size of a
gimple, so they have become retroactively correct again, and only a couple
needed adjustment actually.

Also add a comment that there is now 32 bits of unused padding available in
struct gimple for 64-bit hosts.

-Support for 64-bit location_t: Remove -flarge-source-files

The option -flarge-source-files became unnecessary with 64-bit location_t
and harms performance compared to the new default setting, so silently
ignore it.

libcpp/ChangeLog:

	* include/cpplib.h (struct cpp_token): Adjust comment about the
	struct size.
	* include/line-map.h (location_t): Change typedef from 32-bit to 64-bit
	integer.
	(LINE_MAP_MAX_COLUMN_NUMBER): Increase size to be appropriate for
	64-bit location_t.
	(LINE_MAP_MAX_LOCATION_WITH_PACKED_RANGES): Likewise.
	(LINE_MAP_MAX_LOCATION_WITH_COLS): Likewise.
	(LINE_MAP_MAX_LOCATION): Likewise.
	(MAX_LOCATION_T): Likewise.
	(line_map_suggested_range_bits): Likewise.
	(struct line_map): Adjust comment about the struct size.
	(struct line_map_macro): Likewise.
	(struct line_map_ordinary): Likewise. Rearrange fields to optimize
	padding.

gcc/testsuite/ChangeLog:

	* g++.dg/diagnostic/pr77949.C: Adapt the test for 64-bit location_t,
	when the previously expected failure doesn't actually happen.
	* g++.dg/modules/loc-prune-4.C: Adjust the expected output for the
	64-bit location_t case.
	* gcc.dg/plugin/expensive_selftests_plugin.cc: Don't try to test
	the maximum supported column number in 64-bit location_t mode.
	* gcc.dg/plugin/location_overflow_plugin.cc: Adjust the base_location
	so it can effectively test 64-bit location_t.

gcc/ChangeLog:

	* gimple.h (struct gphi): Update word marking comments to reflect
	the new size of location_t.
	(struct gimple): Likewise. Add a comment about padding.
	* common.opt: Mark -flarge-source-files as Ignored.
	* common.opt.urls: Regenerate.
	* doc/invoke.texi: Remove -flarge-source-files.
	* toplev.cc (process_options): Remove support for
	-flarge-source-files.

1 files changed, 4 insertions, 2 deletions

diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index 298b434..10f0725 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -255,8 +255,10 @@ struct GTY(()) cpp_identifier {
        spelling;
 };
 
-/* A preprocessing token.  This has been carefully packed and should
-   occupy 16 bytes on 32-bit hosts and 24 bytes on 64-bit hosts.  */
+/* A preprocessing token.  This occupies 32 bytes on a 64-bit host.  On a
+   32-bit host it occupies 20 or 24 bytes, depending whether a uint64_t
+   requires 4- or 8-byte alignment.  */
+
 struct GTY(()) cpp_token {
 
   /* Location of first char of token, together with range of full token.  */