[PATCH] libcpp: Replace some macro usage with C++ constructs
David Malcolm
dmalcolm@redhat.com
Wed May 14 14:27:00 GMT 2014
libcpp makes extensive use of the C preprocessor. Whilst this has a
pleasingly self-referential quality, I find the code hard-to-read;
implementing source location support in my JIT branch was much harder than
I hoped it would be.
In an attempt at making the code easier to follow, the following patch
converts some of these macros to C++ equivalents: using "const" for
compile-time constants, and inline functions where macros aren't used as
lvalues.
This effectively documents the expected types of the params, and makes
them available from the debugger e.g.:
(gdb) p LINEMAP_FILE ($3)
$4 = 0x13b8b37 "<command-line>"
Successfully bootstrapped®rtested on x86_64-unknown-linux-gnu
(Fedora 20).
Caveats:
* I didn't mark the inline functions as "static"; should they be?
* I didn't run performance testing on the parser; is there
a recommended way to do this for this kind of change?
OK for trunk?
libcpp/
* include/line-map.h (MAX_SOURCE_LOCATION): Convert from a macro
to a const source_location.
(RESERVED_LOCATION_COUNT): Convert from a macro to a const int.
(LINEMAPS_MAP_INFO): Convert from a macro to a pair of inline
functions, for const/non-const arguments.
(linemap_check_ordinary): Likewise.
(IS_ADHOC_LOC): Convert from a macro to an inline function.
(COMBINE_LOCATION_DATA): Likewise.
(SOURCE_LINE): Likewise.
(SOURCE_COLUMN): Likewise.
(LAST_SOURCE_LINE_LOCATION): Likewise.
(LAST_SOURCE_LINE): Likewise.
(LAST_SOURCE_COLUMN): Likewise.
(INCLUDED_FROM): Likewise.
(MAIN_FILE_P): Likewise.
(source_location): Likewise.
(LINEMAP_FILE): Likewise.
(LINEMAP_LINE): Likewise.
(LINEMAP_SYSP): Likewise.
(linemap_location_before_p): Likewise.
* line-map.c (linemap_check_files_exited): Make local "map" const.
---
libcpp/include/line-map.h | 177 ++++++++++++++++++++++++++++++----------------
libcpp/line-map.c | 2 +-
2 files changed, 118 insertions(+), 61 deletions(-)
diff --git a/libcpp/include/line-map.h b/libcpp/include/line-map.h
index 9886314..4dfb0ae 100644
--- a/libcpp/include/line-map.h
+++ b/libcpp/include/line-map.h
@@ -88,7 +88,7 @@ struct GTY(()) line_map_ordinary {
/* This is the highest possible source location encoded within an
ordinary or macro map. */
-#define MAX_SOURCE_LOCATION 0x7FFFFFFF
+const source_location MAX_SOURCE_LOCATION = 0x7FFFFFFF;
struct cpp_hashnode;
@@ -320,10 +320,21 @@ struct GTY(()) line_maps {
/* Returns the pointer to the memory region where information about
maps are stored in the line table SET. MACRO_MAP_P is a flag
telling if we want macro or ordinary maps. */
-#define LINEMAPS_MAP_INFO(SET, MACRO_MAP_P) \
- ((MACRO_MAP_P) \
- ? &((SET)->info_macro) \
- : &((SET)->info_ordinary))
+inline struct maps_info *
+LINEMAPS_MAP_INFO (line_maps *set, bool macro_map_p)
+{
+ return (macro_map_p
+ ? &(set->info_macro)
+ : &(set->info_ordinary));
+}
+
+inline const struct maps_info *
+LINEMAPS_MAP_INFO (const line_maps *set, bool macro_map_p)
+{
+ return (macro_map_p
+ ? &(set->info_macro)
+ : &(set->info_ordinary));
+}
/* Returns the pointer to the memory region where maps are stored in
the line table SET. MAP_KIND shall be TRUE if we are interested in
@@ -441,9 +452,18 @@ extern void *get_data_from_adhoc_loc (struct line_maps *, source_location);
extern source_location get_location_from_adhoc_loc (struct line_maps *,
source_location);
-#define IS_ADHOC_LOC(LOC) (((LOC) & MAX_SOURCE_LOCATION) != (LOC))
-#define COMBINE_LOCATION_DATA(SET, LOC, BLOCK) \
- get_combined_adhoc_loc ((SET), (LOC), (BLOCK))
+inline bool IS_ADHOC_LOC (source_location loc)
+{
+ return (loc & MAX_SOURCE_LOCATION) != loc;
+}
+
+inline source_location
+COMBINE_LOCATION_DATA (struct line_maps *set,
+ source_location loc,
+ void *block)
+{
+ return get_combined_adhoc_loc (set, loc, block);
+}
extern void rebuild_location_adhoc_htab (struct line_maps *);
@@ -521,66 +541,93 @@ bool linemap_location_from_macro_expansion_p (struct line_maps *,
/* source_location values from 0 to RESERVED_LOCATION_COUNT-1 will
be reserved for libcpp user as special values, no token from libcpp
will contain any of those locations. */
-#define RESERVED_LOCATION_COUNT 2
+const int RESERVED_LOCATION_COUNT = 2;
+
+#if defined ENABLE_CHECKING && (GCC_VERSION >= 2007)
+
+/* Assertion macro to be used in line-map code. */
+#define linemap_assert(EXPR) \
+ do { \
+ if (! (EXPR)) \
+ abort (); \
+ } while (0)
+#else
+#define linemap_assert(EXPR)
+#endif
+
+/* Assert that MAP encodes locations of tokens that are not part of
+ the replacement-list of a macro expansion. */
+inline struct line_map *linemap_check_ordinary (struct line_map *map)
+{
+ linemap_assert (!linemap_macro_expansion_map_p (map));
+ return map;
+}
+
+inline const struct line_map *
+linemap_check_ordinary (const struct line_map *map)
+{
+ linemap_assert (!linemap_macro_expansion_map_p (map));
+ return map;
+}
/* Converts a map and a source_location to source line. */
-#define SOURCE_LINE(MAP, LOC) \
- (((((LOC) - linemap_check_ordinary (MAP)->start_location) \
- >> (MAP)->d.ordinary.column_bits) + (MAP)->d.ordinary.to_line))
+inline linenum_type
+SOURCE_LINE (const struct line_map *map, source_location loc)
+{
+ return ((loc - linemap_check_ordinary (map)->start_location)
+ >> map->d.ordinary.column_bits) + map->d.ordinary.to_line;
+}
/* Convert a map and source_location to source column number. */
-#define SOURCE_COLUMN(MAP, LOC) \
- ((((LOC) - linemap_check_ordinary (MAP)->start_location) \
- & ((1 << (MAP)->d.ordinary.column_bits) - 1)))
+inline linenum_type
+SOURCE_COLUMN (const struct line_map *map, source_location loc)
+{
+ return ((loc - linemap_check_ordinary (map)->start_location)
+ & ((1 << map->d.ordinary.column_bits) - 1));
+}
+
+/* Return the location of the last source line within an ordinary
+ map. */
+inline source_location
+LAST_SOURCE_LINE_LOCATION (const struct line_map *map)
+{
+ return (((linemap_check_ordinary (map)[1].start_location - 1
+ - map->start_location)
+ & ~((1 << map->d.ordinary.column_bits) - 1))
+ + map->start_location);
+}
/* Returns the last source line number within an ordinary map. This
is the (last) line of the #include, or other directive, that caused
a map change. */
-#define LAST_SOURCE_LINE(MAP) \
- SOURCE_LINE (MAP, LAST_SOURCE_LINE_LOCATION (MAP))
+inline linenum_type LAST_SOURCE_LINE (const struct line_map *map)
+{
+ return SOURCE_LINE (map, LAST_SOURCE_LINE_LOCATION (map));
+}
/* Return the last column number within an ordinary map. */
-#define LAST_SOURCE_COLUMN(MAP) \
- SOURCE_COLUMN (MAP, LAST_SOURCE_LINE_LOCATION (MAP))
-/* Return the location of the last source line within an ordinary
- map. */
-#define LAST_SOURCE_LINE_LOCATION(MAP) \
- ((((linemap_check_ordinary (MAP)[1].start_location - 1 \
- - (MAP)->start_location) \
- & ~((1 << (MAP)->d.ordinary.column_bits) - 1)) \
- + (MAP)->start_location))
+inline linenum_type LAST_SOURCE_COLUMN (const struct line_map *map)
+{
+ return SOURCE_COLUMN (map, LAST_SOURCE_LINE_LOCATION (map));
+}
/* Returns the map a given map was included from, or NULL if the map
belongs to the main file, i.e, a file that wasn't included by
another one. */
-#define INCLUDED_FROM(SET, MAP) \
- ((linemap_check_ordinary (MAP)->d.ordinary.included_from == -1) \
- ? NULL \
- : (&LINEMAPS_ORDINARY_MAPS (SET)[(MAP)->d.ordinary.included_from]))
-
-/* Nonzero if the map is at the bottom of the include stack. */
-#define MAIN_FILE_P(MAP) \
- ((linemap_check_ordinary (MAP)->d.ordinary.included_from < 0))
-
-#if defined ENABLE_CHECKING && (GCC_VERSION >= 2007)
-
-/* Assertion macro to be used in line-map code. */
-#define linemap_assert(EXPR) \
- do { \
- if (! (EXPR)) \
- abort (); \
- } while (0)
+inline struct line_map *
+INCLUDED_FROM (struct line_maps *set, const struct line_map *map)
+{
+ return ((linemap_check_ordinary (map)->d.ordinary.included_from == -1)
+ ? NULL
+ : (&LINEMAPS_ORDINARY_MAPS (set)[(map)->d.ordinary.included_from]));
+}
-/* Assert that MAP encodes locations of tokens that are not part of
- the replacement-list of a macro expansion. */
-#define linemap_check_ordinary(LINE_MAP) __extension__ \
- ({linemap_assert (!linemap_macro_expansion_map_p (LINE_MAP)); \
- (LINE_MAP);})
-#else
-#define linemap_assert(EXPR)
-#define linemap_check_ordinary(LINE_MAP) (LINE_MAP)
-#endif
+/* True if the map is at the bottom of the include stack. */
+inline bool MAIN_FILE_P (const struct line_map *map)
+{
+ return linemap_check_ordinary (map)->d.ordinary.included_from < 0;
+}
/* Encode and return a source_location from a column number. The
source line considered is the last source line used to call
@@ -595,19 +642,25 @@ source_location linemap_position_for_line_and_column (struct line_map *,
linenum_type,
unsigned int);
/* Return the file this map is for. */
-#define LINEMAP_FILE(MAP) \
- (linemap_check_ordinary (MAP)->d.ordinary.to_file)
+inline const char * LINEMAP_FILE (const struct line_map *map)
+{
+ return linemap_check_ordinary (map)->d.ordinary.to_file;
+}
/* Return the line number this map started encoding location from. */
-#define LINEMAP_LINE(MAP) \
- (linemap_check_ordinary (MAP)->d.ordinary.to_line)
+inline linenum_type LINEMAP_LINE (const struct line_map *map)
+{
+ return linemap_check_ordinary (map)->d.ordinary.to_line;
+}
/* Return a positive value if map encodes locations from a system
header, 0 otherwise. Returns 1 if MAP encodes locations in a
system header and 2 if it encodes locations in a C system header
that therefore needs to be extern "C" protected in C++. */
-#define LINEMAP_SYSP(MAP) \
- (linemap_check_ordinary (MAP)->d.ordinary.sysp)
+inline unsigned char LINEMAP_SYSP (const struct line_map *map)
+{
+ return linemap_check_ordinary (map)->d.ordinary.sysp;
+}
/* Return a positive value if PRE denotes the location of a token that
comes before the token of POST, 0 if PRE denotes the location of
@@ -620,8 +673,12 @@ int linemap_compare_locations (struct line_maps *set,
/* Return TRUE if LOC_A denotes the location a token that comes
topogically before the token denoted by location LOC_B, or if they
are equal. */
-#define linemap_location_before_p(SET, LOC_A, LOC_B) \
- (linemap_compare_locations ((SET), (LOC_A), (LOC_B)) >= 0)
+inline bool linemap_location_before_p (struct line_maps *set,
+ source_location loc_a,
+ source_location loc_b)
+{
+ return linemap_compare_locations (set, loc_a, loc_b) >= 0;
+}
typedef struct
{
diff --git a/libcpp/line-map.c b/libcpp/line-map.c
index f9a7658..4902fb1 100644
--- a/libcpp/line-map.c
+++ b/libcpp/line-map.c
@@ -189,7 +189,7 @@ linemap_init (struct line_maps *set)
void
linemap_check_files_exited (struct line_maps *set)
{
- struct line_map *map;
+ const struct line_map *map;
/* Depending upon whether we are handling preprocessed input or
not, this can be a user error or an ICE. */
for (map = LINEMAPS_LAST_ORDINARY_MAP (set);
--
1.8.5.3
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