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| author | David Malcolm <dmalcolm@redhat.com> | 2015-05-05 14:21:02 +0000 |
|---|---|---|
| committer | David Malcolm <dmalcolm@gcc.gnu.org> | 2015-05-05 14:21:02 +0000 |
| commit | c87b25e6971b0ca7f8d5a28fa8775594d415d263 (patch) | |
| tree | 7c7a54c3abafff428115672634e58676508baa3c /libcpp | |
| parent | b9066f5ae8c8bb806d173238c3f77097390fa405 (diff) | |
| download | gcc-c87b25e6971b0ca7f8d5a28fa8775594d415d263.zip gcc-c87b25e6971b0ca7f8d5a28fa8775594d415d263.tar.gz gcc-c87b25e6971b0ca7f8d5a28fa8775594d415d263.tar.bz2 | |
libcpp: Improvements to comments in line-map.h/c
libcpp/ChangeLog:
* include/line-map.h: Fix comment at the top of the file.
(source_location): Rewrite and expand the comment for this
typedef, adding an ascii-art table to clarify how source_location
values are allocated.
* line-map.c: Fix comment at the top of the file.
From-SVN: r222806
Diffstat (limited to 'libcpp')
| -rw-r--r-- | libcpp/ChangeLog | 8 | ||||
| -rw-r--r-- | libcpp/include/line-map.h | 71 | ||||
| -rw-r--r-- | libcpp/line-map.c | 2 |
3 files changed, 78 insertions, 3 deletions
diff --git a/libcpp/ChangeLog b/libcpp/ChangeLog index 7f6603d..ba386de 100644 --- a/libcpp/ChangeLog +++ b/libcpp/ChangeLog @@ -1,3 +1,11 @@ +2015-05-05 David Malcolm <dmalcolm@redhat.com> + + * include/line-map.h: Fix comment at the top of the file. + (source_location): Rewrite and expand the comment for this + typedef, adding an ascii-art table to clarify how source_location + values are allocated. + * line-map.c: Fix comment at the top of the file. + 2015-04-09 Richard Biener <rguenther@suse.de> PR pch/65550 diff --git a/libcpp/include/line-map.h b/libcpp/include/line-map.h index 403d798..e1681ea 100644 --- a/libcpp/include/line-map.h +++ b/libcpp/include/line-map.h @@ -1,4 +1,4 @@ -/* Map logical line numbers to (source file, line number) pairs. +/* Map (unsigned int) keys to (source file, line, column) triples. Copyright (C) 2001-2015 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it @@ -46,7 +46,74 @@ enum lc_reason /* The type of line numbers. */ typedef unsigned int linenum_type; -/* A logical line/column number, i.e. an "index" into a line_map. */ +/* The typedef "source_location" is a key within the location database, + identifying a source location or macro expansion. + + This key only has meaning in relation to a line_maps instance. Within + gcc there is a single line_maps instance: "line_table", declared in + gcc/input.h and defined in gcc/input.c. + + The values of the keys are intended to be internal to libcpp, + but for ease-of-understanding the implementation, they are currently + assigned as follows: + + Actual | Value | Meaning + -----------+-------------------------------+------------------------------- + 0x00000000 | | Reserved for use by libcpp + 0x00000001 | RESERVED_LOCATION_COUNT - 1 | Reserved for use by libcpp + -----------+-------------------------------+------------------------------- + 0x00000002 | RESERVED_LOCATION_COUNT | The first location to be + | (also | handed out, and the + | ordmap[0]->start_location) | first line in ordmap 0 + -----------+-------------------------------+------------------------------- + | ordmap[1]->start_location | First line in ordmap 1 + | ordmap[1]->start_location+1 | First column in that line + | ordmap[1]->start_location+2 | 2nd column in that line + | | Subsequent lines are offset by + | | (1 << column_bits), + | | e.g. 128 for 7 bits, with a + | | column value of 0 representing + | | "the whole line". + | ordmap[2]->start_location-1 | Final location in ordmap 1 + -----------+-------------------------------+------------------------------- + | ordmap[2]->start_location | First line in ordmap 2 + | ordmap[3]->start_location-1 | Final location in ordmap 2 + -----------+-------------------------------+------------------------------- + | | (etc) + -----------+-------------------------------+------------------------------- + | ordmap[n-1]->start_location | First line in final ord map + | | (etc) + | set->highest_location - 1 | Final location in that ordmap + -----------+-------------------------------+------------------------------- + | set->highest_location | Location of the where the next + | | ordinary linemap would start + -----------+-------------------------------+------------------------------- + | | + | VVVVVVVVVVVVVVVVVVVVVVVVVVV + | Ordinary maps grow this way + | + | (unallocated integers) + | + | Macro maps grow this way + | ^^^^^^^^^^^^^^^^^^^^^^^^ + | | + -----------+-------------------------------+------------------------------- + | LINEMAPS_MACRO_LOWEST_LOCATION| Locations within macro maps + | macromap[m-1]->start_location | Start of last macro map + | | + -----------+-------------------------------+------------------------------- + | macromap[m-2]->start_location | Start of penultimate macro map + -----------+-------------------------------+------------------------------- + | macromap[1]->start_location | Start of macro map 1 + -----------+-------------------------------+------------------------------- + | macromap[0]->start_location | Start of macro map 0 + 0x7fffffff | MAX_SOURCE_LOCATION | + -----------+-------------------------------+------------------------------- + 0x80000000 | Start of ad-hoc values | + ... | | + 0xffffffff | UINT_MAX | + -----------+-------------------------------+------------------------------- + . */ typedef unsigned int source_location; /* Memory allocation function typedef. Works like xrealloc. */ diff --git a/libcpp/line-map.c b/libcpp/line-map.c index f9260d0..1db59a7 100644 --- a/libcpp/line-map.c +++ b/libcpp/line-map.c @@ -1,4 +1,4 @@ -/* Map logical line numbers to (source file, line number) pairs. +/* Map (unsigned int) keys to (source file, line, column) triples. Copyright (C) 2001-2015 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it |