#ifndef CONFIG←H # define CONFIG←H /* Machine dependent parameters. Some tuning parameters can be found */ /* near the top of gc←private.h. */ /* Machine specific parts contributed by various people. See README file. */ /* Determine the machine type: */ # if defined(sun) && defined(mc68000) # define M68K # define SUNOS # define mach←type←known # endif # if defined(hp9000s300) # define M68K # define HP # define mach←type←known # endif # if defined(vax) # define VAX # ifdef ultrix # define ULTRIX # else # define BSD # endif # define mach←type←known # endif # if defined(mips) # define MIPS # ifdef ultrix # define ULTRIX # else # define RISCOS # endif # define mach←type←known # endif # if defined(sequent) && defined(i386) # define I386 # define SEQUENT # define mach←type←known # endif # if defined(sun) && defined(i386) # define I386 # define SUNOS5 # define mach←type←known # endif # if defined(←←OS2←←) && defined(←←32BIT←←) # define I386 # define OS2 # define mach←type←known # endif # if defined(ibm032) # define RT # define mach←type←known # endif # if defined(sun) && defined(sparc) # define SPARC /* Test for SunOS 5.x */ # include <errno.h> # ifdef ECHRNG # define SUNOS5 # else # define SUNOS4 # endif # define mach←type←known # endif # if defined(←IBMR2) # define IBMRS6000 # define mach←type←known # endif # if defined(SCO) # define I386 # define SCO # define mach←type←known /* --> incompletely implemented */ # endif # if defined(←AUX←SOURCE) # define M68K # define SYSV # define mach←type←known # endif # if defined(←PA←RISC1←0) || defined(←PA←RISC1←1) # define HP←PA # define mach←type←known # endif # if defined(linux) && defined(i386) # define I386 # define LINUX # define mach←type←known # endif /* Feel free to add more clauses here */ /* Or manually define the machine type here. A machine type is */ /* characterized by the architecture. Some */ /* machine types are further subdivided by OS. */ /* the macros ULTRIX, RISCOS, and BSD to distinguish. */ /* Note that SGI IRIX is treated identically to RISCOS. */ /* SYSV on an M68K actually means A/UX. */ /* The distinction in these cases is usually the stack starting address */ # ifndef mach←type←known --> unknown machine type # endif /* Mapping is: M68K ==> Motorola 680X0 */ /* (SUNOS, HP, and SYSV (A/UX) variants)*/ /* M68K←HP ==> HP9000/300 */ /* M68K←SYSV ==> A/UX, maybe others */ /* I386 ==> Intel 386 */ /* (SEQUENT, OS2, SCO, LINUX variants) */ /* SCO is incomplete. */ /* NS32K ==> Encore Multimax */ /* MIPS ==> R2000 or R3000 */ /* (RISCOS, ULTRIX variants) */ /* VAX ==> DEC VAX */ /* (BSD, ULTRIX variants) */ /* RS6000 ==> IBM RS/6000 AIX3.1 */ /* RT ==> IBM PC/RT */ /* HP←PA ==> HP9000/700 & /800 */ /* HP/UX */ /* SPARC ==> SPARC under SunOS */ /* (SUNOS4, SUNOS5 variants) /* * For each architecture and OS, the following need to be defined: * * CPP←WORD←SZ is a simple integer constant representing the word size. * in bits. We assume byte addressibility, where a byte has 8 bits. * We also assume CPP←WORD←SZ is either 32 or 64. Only 32 is completely * implemented. (We care about the length of pointers, not hardware * bus widths. Thus a 64 bit processor with a C compiler that uses * 32 bit pointers should use CPP←WORD←SZ of 32, not 64.) * * MACH←TYPE is a string representation of the machine type. * OS←TYPE is analogous for the OS. * * ALIGNMENT is the largest N, such that * all pointer are guaranteed to be aligned on N byte boundaries. * defining it to be 1 will always work, but perform poorly. * * DATASTART is the beginning of the data segment. * On UNIX systems, the collector will scan the area between DATASTART * and &end for root pointers. * * STACKBOTTOM is the cool end of the stack, which is usually the * highest address in the stack. * Under PCR or OS/2, we have other ways of finding thread stacks. * For each machine, the following should: * 1) define STACK←GROWS←UP if the stack grows toward higher addresses, and * 2) define exactly one of * STACKBOTTOM (should be defined to be an expression) * HEURISTIC1 * HEURISTIC2 * If either of the last two macros are defined, then STACKBOTTOM is computed * during collector startup using one of the following two heuristics: * HEURISTIC1: Take an address inside GC←init's frame, and round it up to * the next multiple of 16 MB. * HEURISTIC2: Take an address inside GC←init's frame, increment it repeatedly * in small steps (decrement if STACK←GROWS←UP), and read the value * at each location. Remember the value when the first * Segmentation violation or Bus error is signalled. Round that * to the nearest plausible page boundary, and use that instead * of STACKBOTTOM. * * If no expression for STACKBOTTOM can be found, and neither of the above * heuristics are usable, the collector can still be used with all of the above * undefined, provided one of the following is done: * 1) GC←mark←roots can be changed to somehow mark from the correct stack(s) * without reference to STACKBOTTOM. This is appropriate for use in * conjunction with thread packages, since there will be multiple stacks. * (Allocating thread stacks in the heap, and treating them as ordinary * heap data objects is also possible as a last resort. However, this is * likely to introduce significant amounts of excess storage retention * unless the dead parts of the thread stacks are periodically cleared.) * 2) Client code may set GC←stackbottom before calling any GC← routines. * If the author of the client code controls the main program, this is * easily accomplished by introducing a new main program, setting * GC←stackbottom to the address of a local variable, and then calling * the original main program. The new main program would read something * like: * * # include "gc←private.h" * * main(argc, argv, envp) * int argc; * char **argv, **envp; * { * int dummy; * * GC←stackbottom = (ptr←t)(&dummy); * return(real←main(argc, argv, envp)); * } */ # ifdef M68K # define MACH←TYPE "M68K" # define ALIGNMENT 2 # ifdef SUNOS # define OS←TYPE "SUNOS" extern char etext; # define DATASTART ((ptr←t)((((word) (&etext)) + 0x1ffff) & ~0x1ffff)) # define HEURISTIC1 /* differs */ # endif # ifdef HP # define OS←TYPE "HP" extern char etext; # define DATASTART ((ptr←t)((((word) (&etext)) + 0xfff) & ~0xfff)) # define STACKBOTTOM ((ptr←t) 0xffeffffc) /* empirically determined. seems to work. */ # endif # ifdef SYSV # define OS←TYPE "SYSV" extern etext; # define DATASTART ((ptr←t)((((word) (&etext)) + 0x3fffff) \ & ~0x3fffff) \ +((word)&etext & 0x1fff)) /* This only works for shared-text binaries with magic number 0413. The other sorts of SysV binaries put the data at the end of the text, in which case the default of &etext would work. Unfortunately, handling both would require having the magic-number available. -- Parag */ # define STACKBOTTOM ((ptr←t)0xFFFFFFFE) /* The stack starts at the top of memory, but */ /* 0x0 cannot be used as setjump←test complains */ /* that the stack direction is incorrect. Two */ /* bytes down from 0x0 should be safe enough. */ /* --Parag */ # endif # endif # ifdef VAX # define MACH←TYPE "VAX" # define ALIGNMENT 4 /* Pointers are longword aligned by 4.2 C compiler */ extern char etext; # define DATASTART ((ptr←t)(&etext)) # ifdef BSD # define OS←TYPE "BSD" # define HEURISTIC1 /* HEURISTIC2 may be OK, but it's hard to test. */ # endif # ifdef ULTRIX # define OS←TYPE "ULTRIX" # define STACKBOTTOM ((ptr←t) 0x7fffc800) # endif # endif # ifdef RT # define MACH←TYPE "RT" # define ALIGNMENT 4 # define DATASTART ((ptr←t) 0x10000000) # define STACKBOTTOM ((ptr←t) 0x1fffd800) # endif # ifdef SPARC # define MACH←TYPE "SPARC" # define ALIGNMENT 4 /* Required by hardware */ extern int etext; # ifdef SUNOS5 # define OS←TYPE "SUNOS5" # define DATASTART ((ptr←t)((((word) (&etext)) + 0x10003) & ~0x3)) /* Experimentally determined. */ /* Inconsistent with man a.out, which appears */ /* to be wrong. */ # endif # ifdef SUNOS4 # define OS←TYPE "SUNOS4" # define DATASTART ((ptr←t)((((word) (&etext)) + 0xfff) & ~0xfff)) /* On very old SPARCs this is too conservative. */ # endif # define HEURISTIC1 # endif # ifdef I386 # define MACH←TYPE "I386" # define ALIGNMENT 4 /* 32-bit compilers align pointers */ # ifdef SEQUENT # define OS←TYPE "SEQUENT" extern int etext; # define DATASTART ((ptr←t)((((word) (&etext)) + 0xfff) & ~0xfff)) # define STACKBOTTOM ((ptr←t) 0x3ffff000) # endif # ifdef SUNOS5 # define OS←TYPE "SUNOS5" extern int etext; # define DATASTART ((ptr←t)((((word) (&etext)) + 0x1003) & ~0x3)) extern int ←start(); # define STACKBOTTOM ((ptr←t)(&←start)) # endif # ifdef SCO # define OS←TYPE "SCO" # define DATASTART ((ptr←t)((((word) (&etext)) + 0x3fffff) \ & ~0x3fffff) \ +((word)&etext & 0xfff)) # define STACKBOTTOM ((ptr←t) 0x7ffffffc) # endif # ifdef LINUX # define OS←TYPE "LINUX" extern int etext; # define DATASTART ((ptr←t)((((word) (&etext)) + 0xfff) & ~0xfff)) # define STACKBOTTOM ((ptr←t)0xc0000000) # endif # ifdef OS2 # define OS←TYPE "OS2" # define DATASTART ((ptr←t)((((word) (&etext)) + 0x3fffff) \ & ~0x3fffff) \ +((word)&etext & 0xfff)) /* STACKBOTTOM is handled specially in GC←init←inner. */ /* OS2 actually has the right system call! */ # endif # endif # ifdef NS32K # define MACH←TYPE "NS32K" # define ALIGNMENT 4 extern char **environ; # define DATASTART ((ptr←t)(&environ)) /* hideous kludge: environ is the first */ /* word in crt0.o, and delimits the start */ /* of the data segment, no matter which */ /* ld options were passed through. */ # define STACKBOTTOM ((ptr←t) 0xfffff000) /* for Encore */ # endif # ifdef MIPS # define MACH←TYPE "MIPS" # define ALIGNMENT 4 /* Required by hardware */ # define DATASTART 0x10000000 /* Could probably be slightly higher since */ /* startup code allocates lots of junk */ # define HEURISTIC2 # endif # ifdef RS6000 # define MACH←TYPE "RS6000" # define ALIGNMENT 4 # define DATASTART ((ptr←t)0x20000000) # define STACKBOTTOM ((ptr←t)0x2ff80000) # endif # ifdef HP←PA # define MACH←TYPE "HP←PA" # define ALIGNMENT 4 extern int ←←data←start; # define DATASTART ((ptr←t)(&←←data←start)) # define HEURISTIC2 # define STACK←GROWS←UP # endif # ifndef STACK←GROWS←UP # define STACK←GROWS←DOWN # endif # ifndef CPP←WORDSZ # define CPP←WORDSZ 32 # endif # ifndef OS←TYPE # define OS←TYPE "" # endif # if CPP←WORDSZ != 32 && CPP←WORDSZ != 64 -> bad word size # endif # ifdef PCR # undef STACKBOTTOM # undef HEURISTIC1 # undef HEURISTIC2 # endif # endif