Commit Graph

3 Commits

Author SHA1 Message Date
Kamalesh Babulal
3ba9a145e9 gcc-plugin: Include additional header for GCC 8
plugin compilation fails on GCC 8:

In file included from gcc-plugins/gcc-common.h:100,
                 from gcc-plugins/ppc64le-plugin.c:1:
/usr/lib/gcc/powerpc64le-linux-gnu/8/plugin/include/attribs.h: In function ‘tree_node* canonicalize_attr_name(tree)’:
/usr/lib/gcc/powerpc64le-linux-gnu/8/plugin/include/attribs.h:118:11: error: ‘get_identifier_with_length’ was not declared in this scope
    return get_identifier_with_length (s + 2, l - 4);
           ^~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/powerpc64le-linux-gnu/8/plugin/include/attribs.h:118:11: note: suggested alternative: ‘get_attr_min_length’
    return get_identifier_with_length (s + 2, l - 4);
           ^~~~~~~~~~~~~~~~~~~~~~~~~~
           get_attr_min_length
Makefile:34: recipe for target 'gcc-plugins/ppc64le-plugin.so' failed

get_identifier_with_length() is defined under stringpool.h, include this
header file for GCC 8, before including attribs.h

Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
2018-05-30 19:39:48 +05:30
Josh Poimboeuf
0019e83622 gcc-plugin: run the plugin at an earlier pass
On ppc64le, building drivers/media/i2c/cx25840/cx25840.ko with GCC 4.85,
the plugin triggers the following errors:

  {standard input}: Assembler messages:
  {standard input}:1078: Error: operand out of range (0x0000000000008fd4 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:1288: Error: operand out of range (0x000000000000874c is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:3844: Error: operand out of range (0x00000000000080e8 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:4028: Error: operand out of range (0x00000000000082b4 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:4031: Error: operand out of range (0x00000000000080b4 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:6661: Error: operand out of range (0x000000000000841c is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:6664: Error: operand out of range (0x0000000000008214 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:6845: Error: operand out of range (0x00000000000089dc is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:6848: Error: operand out of range (0x00000000000087d4 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:7587: Error: operand out of range (0x0000000000008930 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:7590: Error: operand out of range (0x0000000000008728 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  {standard input}:14592: Error: operand out of range (0xffffffffffff79b8 is not between 0xffffffffffff8000 and 0x0000000000007ffc)
  make[1]: *** [drivers/media/i2c/cx25840/cx25840-core.o] Error 1

The problem is that the plugin nops were inserted too late.  GCC laid
out the code with knowledge about the distance between branches, but
then the plugin came along after that and increased the branch distances
by inserting the nops.

Fix it by inserting the nops as early as possible.  The 'vregs' pass is
where the insn codes get initialized, so run the plugin immediately
afterwards.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
2018-03-16 17:16:17 -05:00
Josh Poimboeuf
63a94b8323 gcc-plugin: create a ppc64le GCC plugin which inserts nops after local calls
This is in response to an upstream discussion for the following patch:

  https://lkml.kernel.org/r/1508217523-18885-1-git-send-email-kamalesh@linux.vnet.ibm.com

This should hopefully make it a lot easier for the ppc64le kernel module
code to support klp relocations.

The gcc-common.h and gcc-generate-rtl-pass.h header files are copied
from the upstream Linux source tree.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
2017-11-10 09:17:00 -06:00