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x86: Use -maccumulate-outgoing-args for sane mcount prologues

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commit 746357d (x86: Prevent GCC 4.4.x (pentium-mmx et al) function
prologue wreckage) uses -mtune=generic to work around the function
prologue problem with mcount on -march=pentium-mmx and others.

Jakub pointed out that we can use -maccumulate-outgoing-args instead
which is selected by -mtune=generic and prevents the problem without
losing the -march specific optimizations.

Pointed-out-by: Jakub Jelinek <jakub@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@kernel.org
This commit is contained in:
Thomas Gleixner 2009-11-28 15:03:03 +01:00
parent 746357d6a5
commit b8b7d791a8
1 changed files with 3 additions and 2 deletions
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arch/x86/Makefile_32.cpu
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@ -49,8 +49,9 @@ cflags-$(CONFIG_X86_GENERIC) += $(call tune,generic,$(call tune,i686))
# Work around the pentium-mmx code generator madness of gcc4.4.x which
# does stack alignment by generating horrible code _before_ the mcount
# prologue (push %ebp, mov %esp, %ebp) which breaks the function graph
# tracer assumptions
cflags-$(CONFIG_FUNCTION_GRAPH_TRACER) += $(call cc-option,-mtune=generic)
# tracer assumptions. For i686, generic, core2 this is set by the
# compiler anyway
cflags-$(CONFIG_FUNCTION_GRAPH_TRACER) += $(call cc-option,-maccumulate-outgoing-args)
# Bug fix for binutils: this option is required in order to keep
# binutils from generating NOPL instructions against our will.