objtool: Support GCC 9 cold subfunction naming scheme
authorJosh Poimboeuf <jpoimboe@redhat.com>
Thu, 1 Nov 2018 02:57:30 +0000 (21:57 -0500)
committerThomas Gleixner <tglx@linutronix.de>
Thu, 1 Nov 2018 08:55:38 +0000 (09:55 +0100)
commitbcb6fb5da77c2a228adf07cc9cb1a0c2aa2001c6
treec7e4dc982c044c5758ec2e2f25ade68fb64e9d67
parent5b7449810ae6d652629c550d3974c8453836d229
objtool: Support GCC 9 cold subfunction naming scheme

Starting with GCC 8, a lot of unlikely code was moved out of line to
"cold" subfunctions in .text.unlikely.

For example, the unlikely bits of:

  irq_do_set_affinity()

are moved out to the following subfunction:

  irq_do_set_affinity.cold.49()

Starting with GCC 9, the numbered suffix has been removed.  So in the
above example, the cold subfunction is instead:

  irq_do_set_affinity.cold()

Tweak the objtool subfunction detection logic so that it detects both
GCC 8 and GCC 9 naming schemes.

Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/015e9544b1f188d36a7f02fa31e9e95629aa5f50.1541040800.git.jpoimboe@redhat.com
tools/objtool/elf.c