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/* Machine-specific calling sequence for `mcount' profiling function. ia64
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Copyright (C) 2000 Free Software Foundation, Inc.
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Contributed by David Mosberger <davidm@hpl.hp.com>
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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/* Assembly stub to invoke _mcount(). Compiler generated code calls
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this stub before executing a function's prologue and without saving
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any registers. It is therefore necessary to preserve the input
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registers as they may contain function arguments. To work
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correctly with frame-less functions, it is also necessary to
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preserve the return pointer (b0 aka rp).
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State upon entering _mcount:
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r8 address of return value structure (used only when called
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function returns a large structure)
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r15 static link (used only for nested functions)
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in0 ar.pfs to restore before returning to the function that
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in1 gp value to restore before returning to the function that
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in2 return address in the function that invoked the caller
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in3 address of the global-offset table entry that holds the
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profile count dword allocated by the compiler; to get
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the address of this dword, use "ld8 in2=[in2]; this
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dword can be used in any way by _mcount (including
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not at all, as is the case with the current implementation)
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b0 address to return to after _mcount is done
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.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(4)
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alloc loc1 = ar.pfs, 4, 4, 3, 0
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mov loc2 = r8 // gcc uses r8 to pass pointer to return structure
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mov loc3 = r15 // gcc uses r15 to pass the static link to nested functions
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br.call.sptk.few rp = __mcount
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adds r2 = _mcount_ret_helper - .here, r2
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LOCAL_LEAF(_mcount_ret_helper)
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alloc r2 = ar.pfs, 0, 0, 8, 0
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END(_mcount_ret_helper)
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weak_alias (_mcount, mcount)