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[PATCH] ppc64: remove -fno-omit-frame-pointer

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During some code inspection using gcc 4.0 I noticed a stack frame was being
created for a number of functions that didnt require it.  For example:

c0000000000df944 <._spin_unlock>:
c0000000000df944:       fb e1 ff f0     std     r31,-16(r1)
c0000000000df948:       f8 21 ff c1     stdu    r1,-64(r1)
c0000000000df94c:       7c 3f 0b 78     mr      r31,r1
c0000000000df950:       7c 20 04 ac     lwsync
c0000000000df954:       e8 21 00 00     ld      r1,0(r1)
c0000000000df958:       38 00 00 00     li      r0,0
c0000000000df95c:       90 03 00 00     stw     r0,0(r3)
c0000000000df960:       eb e1 ff f0     ld      r31,-16(r1)
c0000000000df964:       4e 80 00 20     blr

It turns out we are adding -fno-omit-frame-pointer to ppc64 which is
causing the above behaviour.  Removing that flag results in much better
code:

c0000000000d5b30 <._spin_unlock>:
c0000000000d5b30:       7c 20 04 ac     lwsync
c0000000000d5b34:       38 00 00 00     li      r0,0
c0000000000d5b38:       90 03 00 00     stw     r0,0(r3)
c0000000000d5b3c:       4e 80 00 20     blr

We dont require a frame pointer to debug on ppc64, so remove it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Anton Blanchard 2005-04-16 15:24:37 -07:00 committed by Linus Torvalds
parent 50bfb2e032
commit 89e09f5ebb
1 changed files with 0 additions and 4 deletions
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arch/ppc64/Kconfig
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@ -40,10 +40,6 @@ config COMPAT
bool
default y
config FRAME_POINTER
bool
default y
# We optimistically allocate largepages from the VM, so make the limit
# large enough (16MB). This badly named config option is actually
# max order + 1