1 /*- 2 * SPDX-License-Identifier: MIT-CMU 3 * 4 * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University. 5 * All rights reserved. 6 * 7 * Author: Chris G. Demetriou 8 * 9 * Permission to use, copy, modify and distribute this software and 10 * its documentation is hereby granted, provided that both the copyright 11 * notice and this permission notice appear in all copies of the 12 * software, derivative works or modified versions, and any portions 13 * thereof, and that both notices appear in supporting documentation. 14 * 15 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 16 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 17 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 18 * 19 * Carnegie Mellon requests users of this software to return to 20 * 21 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 22 * School of Computer Science 23 * Carnegie Mellon University 24 * Pittsburgh PA 15213-3890 25 * 26 * any improvements or extensions that they make and grant Carnegie the 27 * rights to redistribute these changes. 28 * 29 * from: NetBSD: profile.h,v 1.9 1997/04/06 08:47:37 cgd Exp 30 * from: FreeBSD: src/sys/alpha/include/profile.h,v 1.4 1999/12/29 31 * $FreeBSD$ 32 */ 33 34 #ifdef __arm__ 35 #include <arm/profile.h> 36 #else /* !__arm__ */ 37 38 #ifndef _MACHINE_PROFILE_H_ 39 #define _MACHINE_PROFILE_H_ 40 41 #define FUNCTION_ALIGNMENT 32 42 43 typedef u_long fptrdiff_t; 44 45 #ifndef _KERNEL 46 47 #include <sys/cdefs.h> 48 49 typedef __uintfptr_t uintfptr_t; 50 51 #define _MCOUNT_DECL \ 52 static void _mcount(uintfptr_t frompc, uintfptr_t selfpc) __used; \ 53 static void _mcount 54 55 /* 56 * Call into _mcount. On arm64 the .mcount is a function so callers will 57 * handle caller saved registers. As we don't directly touch any callee 58 * saved registers we can just load the two arguments and use a tail call 59 * into the MI _mcount function. 60 * 61 * When building with gcc frompc will be in x0, however this is not the 62 * case on clang. As such we need to load it from the stack. As long as 63 * the caller follows the ABI this will load the correct value. 64 */ 65 #define MCOUNT __asm( \ 66 " .text \n" \ 67 " .align 6 \n" \ 68 " .type .mcount,#function \n" \ 69 " .globl .mcount \n" \ 70 " .mcount: \n" \ 71 " .cfi_startproc \n" \ 72 /* Load the caller return address as frompc */ \ 73 " ldr x0, [x29, #8] \n" \ 74 /* Use our return address as selfpc */ \ 75 " mov x1, lr \n" \ 76 " b _mcount \n" \ 77 " .cfi_endproc \n" \ 78 " .size .mcount, . - .mcount \n" \ 79 ); 80 #if 0 81 /* 82 * If clang passed frompc correctly we could implement it like this, however 83 * all clang versions we care about would need to be fixed before we could 84 * make this change. 85 */ 86 void 87 mcount(uintfptr_t frompc) 88 { 89 _mcount(frompc, __builtin_return_address(0)); 90 } 91 #endif 92 93 #endif /* !_KERNEL */ 94 95 #endif /* !_MACHINE_PROFILE_H_ */ 96 97 #endif /* !__arm__ */ 98