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authorUlrich Weigand <Ulrich.Weigand@de.ibm.com>2013-12-04 06:55:03 -0600
committerAdhemerval Zanella <azanella@linux.vnet.ibm.com>2013-12-04 07:41:39 -0600
commit8b8a692cfd7d80f1ee7c8b9ab356a259367dd187 (patch)
tree7740d5d71feed939fb59df34e1f3535fb14e990f /sysdeps/powerpc/powerpc64/crtn.S
parent122b66defdb9e4ded3ccc5c2b290f0520c6fa3cd (diff)
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PowerPC64 ELFv2 ABI 4/6: Stack frame layout changes
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout.  These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.html
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html

Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.

In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.

To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets.  Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.

The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.

The second change only affected a few assembler files that used
the save area to temporarily store some registers.  In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer.  Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
Diffstat (limited to 'sysdeps/powerpc/powerpc64/crtn.S')
-rw-r--r--sysdeps/powerpc/powerpc64/crtn.S8
1 files changed, 4 insertions, 4 deletions
diff --git a/sysdeps/powerpc/powerpc64/crtn.S b/sysdeps/powerpc/powerpc64/crtn.S
index 364e53aae7..cdd3b0f340 100644
--- a/sysdeps/powerpc/powerpc64/crtn.S
+++ b/sysdeps/powerpc/powerpc64/crtn.S
@@ -39,13 +39,13 @@
 #include <sysdep.h>
 
 	.section .init,"ax",@progbits
-	addi r1, r1, 112
-	ld r0, 16(r1)
+	addi r1, r1, FRAME_MIN_SIZE_PARM
+	ld r0, FRAME_LR_SAVE(r1)
 	mtlr r0
 	blr
 
 	.section .fini,"ax",@progbits
-	addi r1, r1, 112
-	ld r0, 16(r1)
+	addi r1, r1, FRAME_MIN_SIZE_PARM
+	ld r0, FRAME_LR_SAVE(r1)
 	mtlr r0
 	blr