/* Machine-specific calling sequence for `mcount' profiling function. ia64 Copyright (C) 2000 Free Software Foundation, Inc. Contributed by David Mosberger <davidm@hpl.hp.com> 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. */ /* Assembly stub to invoke _mcount(). Compiler generated code calls this stub before executing a function's prologue and without saving any registers. It is therefore necessary to preserve the input registers as they may contain function arguments. To work correctly with frame-less functions, it is also necessary to preserve the return pointer (b0 aka rp). State upon entering _mcount: r8 address of return value structure (used only when called function returns a large structure) r15 static link (used only for nested functions) in0 ar.pfs to restore before returning to the function that called _mcount in1 gp value to restore before returning to the function that called _mcount in2 return address in the function that invoked the caller of _mcount (frompc) in3 address of the global-offset table entry that holds the profile count dword allocated by the compiler; to get the address of this dword, use "ld8 in2=[in2]; this dword can be used in any way by _mcount (including not at all, as is the case with the current implementation) b0 address to return to after _mcount is done */ #include <sysdep.h> #undef ret LEAF(_mcount) .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(4) alloc loc1 = ar.pfs, 4, 4, 3, 0 mov loc0 = rp .body mov loc2 = r8 // gcc uses r8 to pass pointer to return structure ;; mov loc3 = r15 // gcc uses r15 to pass the static link to nested functions mov out0 = in2 mov out1 = rp br.call.sptk.few rp = __mcount ;; .here: { .mii mov gp = in1 mov r2 = ip mov ar.pfs = loc1 } ;; adds r2 = _mcount_ret_helper - .here, r2 mov b7 = loc0 mov rp = in2 ;; mov r8 = loc2 mov r15 = loc3 mov b6 = r2 br.ret.sptk.few b6 END(_mcount) LOCAL_LEAF(_mcount_ret_helper) .prologue .altrp b7 .save ar.pfs, r40 .body alloc r2 = ar.pfs, 0, 0, 9, 0 mov ar.pfs = r40 br b7 END(_mcount_ret_helper) weak_alias (_mcount, mcount)