59c36f97db
spotted assignments to volatile variables which were neither placed
inside the mmapped ROM area nor were they counters.
Due to the use of accessor functions, volatile usage can be reduced
significantly because the accessor functions take care of actually
performing the reads/writes correctly.
The following semantic patch spotted them (linebreak in python string
for readability reasons, please remove before usage):
@r exists@
expression b;
typedef uint8_t;
volatile uint8_t a;
position p1;
@@
a@p1 = readb(b);
@script:python@
p1 << r.p1;
a << r.a;
b << r.b;
@@
print "* file: %s line %s has assignment to unnecessarily volatile
variable: %s = readb(%s);" % (p1[0].file, p1[0].line, a, b)
Result was:
HANDLING: sst28sf040.c
* file: sst28sf040.c line 44 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 43 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 42 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 41 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 40 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 39 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 38 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 58 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 57 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 56 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 55 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 54 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 53 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
* file: sst28sf040.c line 52 has assignment to unnecessarily volatile
variable: tmp = readb(TODO: Binary);
The following semantic patch uses the spatch builtin match printing
functionality by prepending a "*" to the line with the pattern:
@@
expression b;
typedef uint8_t;
volatile uint8_t a;
@@
* a = readb(b);
Result is:
HANDLING: sst28sf040.c
diff =
--- sst28sf040.c 2009-03-06 01:04:49.000000000 +0100
@@ -35,13 +35,6 @@ static __inline__ void protect_28sf040(v
/* ask compiler not to optimize this */
volatile uint8_t tmp;
- tmp = readb(bios + 0x1823);
- tmp = readb(bios + 0x1820);
- tmp = readb(bios + 0x1822);
- tmp = readb(bios + 0x0418);
- tmp = readb(bios + 0x041B);
- tmp = readb(bios + 0x0419);
- tmp = readb(bios + 0x040A);
}
static __inline__ void unprotect_28sf040(volatile uint8_t *bios)
@@ -49,13 +42,6 @@ static __inline__ void unprotect_28sf040
/* ask compiler not to optimize this */
volatile uint8_t tmp;
- tmp = readb(bios + 0x1823);
- tmp = readb(bios + 0x1820);
- tmp = readb(bios + 0x1822);
- tmp = readb(bios + 0x0418);
- tmp = readb(bios + 0x041B);
- tmp = readb(bios + 0x0419);
- tmp = readb(bios + 0x041A);
}
static __inline__ int erase_sector_28sf040(volatile uint8_t *bios,
It's arguably a bit easier to read if you get used to the leading "-"
for matching lines.
This patch was enabled by Coccinelle:
http://www.emn.fr/x-info/coccinelle/
Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Joseph Smith <joe@settoplinux.org>
--
http://www.hailfinger.org/
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@3973 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
|
||
|---|---|---|
| documentation | ||
| payloads | ||
| src | ||
| targets | ||
| util | ||
| COPYING | ||
| NEWS | ||
| README | ||
README
------------------------------------------------------------------------------- Coreboot README ------------------------------------------------------------------------------- Coreboot is a Free Software project aimed at replacing the proprietary BIOS you can find in most of today's computers. It performs just a little bit of hardware initialization and then executes one of many possible payloads, e.g. a Linux kernel. Payloads -------- After the basic initialization of the hardware has been performed, any desired "payload" can be started by coreboot. Examples include: * A Linux kernel * FILO (a simple bootloader with filesystem support) * GRUB2 (a free bootloader; support is in development) * OpenBIOS (a free IEEE1275-1994 Open Firmware implementation) * Open Firmware (a free IEEE1275-1994 Open Firmware implementation) * SmartFirmware (a free IEEE1275-1994 Open Firmware implementation) * GNUFI (a free, UEFI-compatible firmware) * Etherboot (for network booting and booting from raw IDE or FILO) * ADLO (for booting Windows 2000 or OpenBSD) * Plan 9 (a distributed operating system) * memtest86 (for testing your RAM) Supported Hardware ------------------ Coreboot supports a wide range of chipsets, devices, and mainboards. For details please consult: * http://www.coreboot.org/Supported_Motherboards * http://www.coreboot.org/Supported_Chipsets_and_Devices Website and Mailing List ------------------------ Further details on the project, a FAQ, many HOWTOs, news, development guidelines and more can be found on the coreboot website: http://www.coreboot.org You can contact us directly on the coreboot mailing list: http://www.coreboot.org/Mailinglist Copyright and License --------------------- The copyright on coreboot is owned by quite a large number of individual developers and companies. Please check the individual source files for details. Coreboot is licensed under the terms of the GNU General Public License (GPL). Some files are licensed under the "GPL (version 2, or any later version)", and some files (mostly those derived from the Linux kernel) are licensed under the "GPL, version 2". For some parts, which were derived from other projects, other (GPL-compatible) licenses may apply. Please check the individual source files for details. This makes the resulting coreboot images licensed under the GPL, version 2.