/* * Coyright (c) 2005-2008 Apple Computer, Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* * Syscall argument mungers. * * The data to be munged has been explicitly copied in to the argument area, * and will be munged in place in the uu_arg[] array. Because of this, the * functions all take the same arguments as their PPC equivalents, but the * first argument is ignored. These mungers are for 32-bit app's syscalls, * since 64-bit args are stored into the save area (which overlays the * uu_args) in the order the syscall ABI calls for. * * The issue is that the incoming args are 32-bit, but we must expand * them in place into 64-bit args, as if they were from a 64-bit process. * * There are several functions in this file. Each takes two parameters: * * void munge_XXXX(const void *regs, // %rdi * void *uu_args); // %rsi * * The name of the function encodes the number and type of the parameters, * as follows: * * w = a 32-bit value such as an int or a 32-bit ptr, that does not * require sign extension. These are handled by zeroing a word * of output, and copying a word from input to output. * * s = a 32-bit value such as a long, which must be sign-extended to * a 64-bit long-long in the uu_args. These are handled by * loading a word of input and sign extending it to a double, * and storing two words of output. * * l = a 64-bit long-long. These are handled by copying two words * of input to the output. * * For example, "munge_wls" takes a word, a long-long, and a word. This * takes four words in the uu_arg[] area: the first word is in one, the * long-long takes two, and the final word is in the fourth. We store six * words: the low word is left in place, followed by a 0, followed by the * two words of the long-long, followed by the low word and the sign extended * high word of the preceeding low word. * * Because this is an in-place modification, we actually start at the end * of uu_arg[] and work our way back to the beginning of the array. * * As you can see, we save a lot of code by collapsing mungers that are * prefixes or suffixes of each other. */ #include ENTRY(munge_w) movl $0,4(%rsi) ret ENTRY(munge_ww) xorl %edx,%edx jmp Lw2 ENTRY(munge_www) xorl %edx,%edx jmp Lw3 ENTRY(munge_wwww) xorl %edx,%edx jmp Lw4 ENTRY(munge_wwwww) xorl %edx,%edx jmp Lw5 ENTRY(munge_wwwwww) xorl %edx,%edx jmp Lw6 ENTRY(munge_wwwwwww) xorl %edx,%edx jmp Lw7 ENTRY(munge_wwwwwwww) xorl %edx,%edx movl 28(%rsi),%eax movl %eax,56(%rsi) movl %edx,60(%rsi) Lw7: movl 24(%rsi),%eax movl %eax,48(%rsi) movl %edx,52(%rsi) Lw6: movl 20(%rsi),%eax movl %eax,40(%rsi) movl %edx,44(%rsi) Lw5: movl 16(%rsi),%eax movl %eax,32(%rsi) movl %edx,36(%rsi) Lw4: movl 12(%rsi),%eax movl %eax,24(%rsi) movl %edx,28(%rsi) Lw3: movl 8(%rsi),%eax movl %eax,16(%rsi) movl %edx,20(%rsi) Lw2: movl 4(%rsi),%eax movl %eax,8(%rsi) movl %edx,12(%rsi) movl %edx,4(%rsi) ret Entry(munge_wl) /* Costs an extra w move to do this */ ENTRY(munge_wlw) xorl %edx,%edx movl 12(%rsi),%eax movl %eax,16(%rsi) movl %edx,20(%rsi) movl 8(%rsi),%eax movl %eax,12(%rsi) movl 4(%rsi),%eax movl %eax,8(%rsi) movl %edx,4(%rsi) ret Entry(munge_wwwlw) xorl %edx,%edx movl 20(%rsi),%eax movl %eax,32(%rsi) movl %edx,36(%rsi) jmp Lwwwl ENTRY(munge_wwwl) xorl %edx,%edx Lwwwl: movl 12(%rsi),%eax movl %eax,24(%rsi) movl 16(%rsi),%eax movl %eax,28(%rsi) jmp Lw3 ENTRY(munge_wwwwlw) xorl %edx,%edx movl 24(%rsi),%eax movl %eax,40(%rsi) movl %edx,44(%rsi) jmp Lwwwwl ENTRY(munge_wwwwl) xorl %edx,%edx Lwwwwl: movl 16(%rsi),%eax movl %eax,32(%rsi) movl 20(%rsi),%eax movl %eax,36(%rsi) jmp Lw4 ENTRY(munge_wwwwwl) xorl %edx,%edx movl 20(%rsi),%eax movl %eax,40(%rsi) movl 24(%rsi),%eax movl %eax,44(%rsi) jmp Lw5 ENTRY(munge_wwwwwwlw) xorl %edx,%edx movl 32(%rsi),%eax movl %eax,56(%rsi) movl %edx,60(%rsi) movl 24(%rsi),%eax movl %eax,48(%rsi) movl 28(%rsi),%eax movl %eax,52(%rsi) jmp Lw6 ENTRY(munge_wwwwwwll) xorl %edx,%edx movl 32(%rsi),%eax movl %eax,56(%rsi) movl 36(%rsi),%eax movl %eax,60(%rsi) movl 24(%rsi),%eax movl %eax,48(%rsi) movl 28(%rsi),%eax movl %eax,52(%rsi) jmp Lw6 ENTRY(munge_wsw) movl 8(%rsi),%eax movl %eax,16(%rsi) movl $0,20(%rsi) movl 4(%rsi),%eax cltd movl %eax,8(%rsi) movl %edx,12(%rsi) movl $0,4(%rsi) ret ENTRY(munge_wws) movl 8(%rsi),%eax cltd movl %eax,16(%rsi) movl %edx,20(%rsi) xorl %edx,%edx jmp Lw2 ENTRY(munge_wwwsw) movl 16(%rsi),%eax movl %eax,32(%rsi) movl $0,36(%rsi) movl 12(%rsi),%eax cltd movl %eax,24(%rsi) movl %edx,28(%rsi) xorl %edx,%edx jmp Lw3 ENTRY(munge_llllll) ret // nothing to do here, either - all args are already // 64-bit and do not require sign/zero extension // also, there is no mixing in of shorter args that // do need extension