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diff --git a/libc/sysdeps/linux/powerpc/mcount.S b/libc/sysdeps/linux/powerpc/mcount.S
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+/* PowerPC-specific implementation of profiling support.
+ Copyright (C) 1997, 1999 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <features.h>
+#include "ppc_asm.h"
+
+/* This would be bad. */
+#ifdef PROF
+#undef PROF
+#endif
+
+
+/* We do profiling as described in the SYSV ELF ABI, _mcount is called
+ with the address of a data word in r0 (that is different for every
+ routine, initialised to 0, and otherwise unused). The caller has put
+ the address the caller will return to in the usual place on the stack,
+ 4(r1). _mcount is responsible for ensuring that when it returns no
+ argument-passing registers are disturbed, and that the LR is set back
+ to (what the caller sees as) 4(r1).
+
+ This is intended so that the following code can be inserted at the
+ front of any routine without changing the routine:
+
+ .data
+ .align 2
+ 0: .long 0
+ .previous
+ mflr r0
+ lis r11,0b@ha
+ stw r0,4(r1)
+ addi r0,r11,0b@l
+ bl _mcount
+*/
+
+
+.globl _mcount;
+.type _mcount, @function;
+.align 2;
+
+_mcount:
+ stwu r1,-48(r1)
+/* We need to save the parameter-passing registers. */
+ stw r3, 12(r1)
+ stw r4, 16(r1)
+ stw r5, 20(r1)
+ stw r6, 24(r1)
+ mflr r4
+ lwz r3, 52(r1)
+ mfcr r5
+ stw r7, 28(r1)
+ stw r8, 32(r1)
+ stw r9, 36(r1)
+ stw r10,40(r1)
+ stw r4, 44(r1)
+ stw r5, 8(r1)
+#ifdef PIC
+ bl __mcount_internal@plt
+#else
+ bl __mcount_internal
+#endif
+ nop
+ /* Restore the registers... */
+ lwz r6, 8(r1)
+ lwz r0, 44(r1)
+ lwz r3, 12(r1)
+ mtctr r0
+ lwz r4, 16(r1)
+ mtcrf 0xff,r6
+ lwz r5, 20(r1)
+ lwz r6, 24(r1)
+ lwz r0, 52(r1)
+ lwz r7, 28(r1)
+ lwz r8, 32(r1)
+ mtlr r0
+ lwz r9, 36(r1)
+ lwz r10,40(r1)
+ /* ...unwind the stack frame, and return to your usual programming. */
+ addi r1,r1,48
+ bctr
+ .size _mcount,.-_mcount;
+
+#undef mcount
+.weak mcount ; mcount = _mcount
+