/* * Meta dynamic resolver * * Copyright (C) 2013 Imagination Technologies Ltd. * * Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball. * * This function is _not_ called directly. It is jumped to (so no return * address is on the stack) when attempting to use a symbol that has not yet * been resolved. The first time a jump symbol (such as a function call inside * a shared library) is used (before it gets resolved) it will jump here to * _dl_linux_resolve. When we get called the stack looks like this: * reloc_entry * tpnt * * This function saves all the registers then makes the function call * _dl_linux_resolver(tpnt, reloc_entry). _dl_linux_resolver() figures out * where the jump symbol is _really_ supposed to have jumped to and returns * that to us. Once we have that, we overwrite tpnt with this fixed up * address. We then clean up after ourselves, put all the registers back how we * found them, then we jump to the fixed up address, which is where the jump * symbol that got us here really wanted to jump to in the first place. * -Erik Andersen */ .text .global __dl_linux_resolve .type __dl_linux_resolve,@function __dl_linux_resolve: !! Save registers on the stack. Do we need to save any more here? MSETL [A0StP++],D0Ar6,D0Ar4,D0Ar2,D0FrT SETL [A0StP++],A0FrP,A1LbP !! Get the args for _dl_linux_resolver off the stack GETL D0Re0,D1Re0,[A0StP+#-(6*8)] GETD D1Ar1,[D0Re0] MOV D0Ar2,D1Re0 !! Multiply plt_index by sizeof(Elf32_Rela) MULW D0Ar2,D0Ar2,#12 !! Call the resolver CALLR D1RtP,__dl_linux_resolver !! Restore the registers from the stack SUB A0.2,A0StP,#(1*8) GETL A0FrP,A1LbP,[A0.2] SUB A0.2,A0.2,#(4*8) MGETL D0Ar6,D0Ar4,D0Ar2,D0FrT,[A0.2] !! Also take into account args pushed by PLT SUB A0StP,A0StP,#(6*8) !! Jump to the resolved address MOV PC,D0Re0 .size __dl_linux_resolve, .-__dl_linux_resolve