diff options
Diffstat (limited to 'gnulib/import/alloca.c')
| -rw-r--r-- | gnulib/import/alloca.c | 286 |
1 files changed, 4 insertions, 282 deletions
diff --git a/gnulib/import/alloca.c b/gnulib/import/alloca.c index d0476d53e6c..91b9ec38916 100644 --- a/gnulib/import/alloca.c +++ b/gnulib/import/alloca.c @@ -39,8 +39,8 @@ # define memory_full() abort () #endif -/* If compiling with GCC 2, this file's not needed. */ -#if !defined (__GNUC__) || __GNUC__ < 2 +/* If compiling with GCC or clang, this file is not needed. */ +#if !(defined __GNUC__ || defined __clang__) /* If someone has defined alloca as a macro, there must be some other way alloca is supposed to work. */ @@ -62,16 +62,6 @@ lose # endif /* static */ # endif /* emacs */ -/* If your stack is a linked list of frames, you have to - provide an "address metric" ADDRESS_FUNCTION macro. */ - -# if defined (CRAY) && defined (CRAY_STACKSEG_END) -long i00afunc (); -# define ADDRESS_FUNCTION(arg) (char *) i00afunc (&(arg)) -# else -# define ADDRESS_FUNCTION(arg) &(arg) -# endif - /* Define STACK_DIRECTION if you know the direction of stack growth for your system; otherwise it will be automatically deduced at run-time. @@ -140,7 +130,7 @@ void * alloca (size_t size) { auto char probe; /* Probes stack depth: */ - register char *depth = ADDRESS_FUNCTION (probe); + register char *depth = &probe; # if STACK_DIRECTION == 0 if (STACK_DIR == 0) /* Unknown growth direction. */ @@ -206,273 +196,5 @@ alloca (size_t size) } } -# if defined (CRAY) && defined (CRAY_STACKSEG_END) - -# ifdef DEBUG_I00AFUNC -# include <stdio.h> -# endif - -# ifndef CRAY_STACK -# define CRAY_STACK -# ifndef CRAY2 -/* Stack structures for CRAY-1, CRAY X-MP, and CRAY Y-MP */ -struct stack_control_header - { - long shgrow:32; /* Number of times stack has grown. */ - long shaseg:32; /* Size of increments to stack. */ - long shhwm:32; /* High water mark of stack. */ - long shsize:32; /* Current size of stack (all segments). */ - }; - -/* The stack segment linkage control information occurs at - the high-address end of a stack segment. (The stack - grows from low addresses to high addresses.) The initial - part of the stack segment linkage control information is - 0200 (octal) words. This provides for register storage - for the routine which overflows the stack. */ - -struct stack_segment_linkage - { - long ss[0200]; /* 0200 overflow words. */ - long sssize:32; /* Number of words in this segment. */ - long ssbase:32; /* Offset to stack base. */ - long:32; - long sspseg:32; /* Offset to linkage control of previous - segment of stack. */ - long:32; - long sstcpt:32; /* Pointer to task common address block. */ - long sscsnm; /* Private control structure number for - microtasking. */ - long ssusr1; /* Reserved for user. */ - long ssusr2; /* Reserved for user. */ - long sstpid; /* Process ID for pid based multi-tasking. */ - long ssgvup; /* Pointer to multitasking thread giveup. */ - long sscray[7]; /* Reserved for Cray Research. */ - long ssa0; - long ssa1; - long ssa2; - long ssa3; - long ssa4; - long ssa5; - long ssa6; - long ssa7; - long sss0; - long sss1; - long sss2; - long sss3; - long sss4; - long sss5; - long sss6; - long sss7; - }; - -# else /* CRAY2 */ -/* The following structure defines the vector of words - returned by the STKSTAT library routine. */ -struct stk_stat - { - long now; /* Current total stack size. */ - long maxc; /* Amount of contiguous space which would - be required to satisfy the maximum - stack demand to date. */ - long high_water; /* Stack high-water mark. */ - long overflows; /* Number of stack overflow ($STKOFEN) calls. */ - long hits; /* Number of internal buffer hits. */ - long extends; /* Number of block extensions. */ - long stko_mallocs; /* Block allocations by $STKOFEN. */ - long underflows; /* Number of stack underflow calls ($STKRETN). */ - long stko_free; /* Number of deallocations by $STKRETN. */ - long stkm_free; /* Number of deallocations by $STKMRET. */ - long segments; /* Current number of stack segments. */ - long maxs; /* Maximum number of stack segments so far. */ - long pad_size; /* Stack pad size. */ - long current_address; /* Current stack segment address. */ - long current_size; /* Current stack segment size. This - number is actually corrupted by STKSTAT to - include the fifteen word trailer area. */ - long initial_address; /* Address of initial segment. */ - long initial_size; /* Size of initial segment. */ - }; - -/* The following structure describes the data structure which trails - any stack segment. I think that the description in 'asdef' is - out of date. I only describe the parts that I am sure about. */ - -struct stk_trailer - { - long this_address; /* Address of this block. */ - long this_size; /* Size of this block (does not include - this trailer). */ - long unknown2; - long unknown3; - long link; /* Address of trailer block of previous - segment. */ - long unknown5; - long unknown6; - long unknown7; - long unknown8; - long unknown9; - long unknown10; - long unknown11; - long unknown12; - long unknown13; - long unknown14; - }; - -# endif /* CRAY2 */ -# endif /* not CRAY_STACK */ - -# ifdef CRAY2 -/* Determine a "stack measure" for an arbitrary ADDRESS. - I doubt that "lint" will like this much. */ - -static long -i00afunc (long *address) -{ - struct stk_stat status; - struct stk_trailer *trailer; - long *block, size; - long result = 0; - - /* We want to iterate through all of the segments. The first - step is to get the stack status structure. We could do this - more quickly and more directly, perhaps, by referencing the - $LM00 common block, but I know that this works. */ - - STKSTAT (&status); - - /* Set up the iteration. */ - - trailer = (struct stk_trailer *) (status.current_address - + status.current_size - - 15); - - /* There must be at least one stack segment. Therefore it is - a fatal error if "trailer" is null. */ - - if (trailer == NULL) - abort (); - - /* Discard segments that do not contain our argument address. */ - - while (trailer != NULL) - { - block = (long *) trailer->this_address; - size = trailer->this_size; - if (block == NULL || size == 0) - abort (); - trailer = (struct stk_trailer *) trailer->link; - if ((block <= address) && (address < (block + size))) - break; - } - - /* Set the result to the offset in this segment and add the sizes - of all predecessor segments. */ - - result = address - block; - - if (trailer == NULL) - { - return result; - } - - do - { - if (trailer->this_size <= 0) - abort (); - result += trailer->this_size; - trailer = (struct stk_trailer *) trailer->link; - } - while (trailer != NULL); - - /* We are done. Note that if you present a bogus address (one - not in any segment), you will get a different number back, formed - from subtracting the address of the first block. This is probably - not what you want. */ - - return (result); -} - -# else /* not CRAY2 */ -/* Stack address function for a CRAY-1, CRAY X-MP, or CRAY Y-MP. - Determine the number of the cell within the stack, - given the address of the cell. The purpose of this - routine is to linearize, in some sense, stack addresses - for alloca. */ - -static long -i00afunc (long address) -{ - long stkl = 0; - - long size, pseg, this_segment, stack; - long result = 0; - - struct stack_segment_linkage *ssptr; - - /* Register B67 contains the address of the end of the - current stack segment. If you (as a subprogram) store - your registers on the stack and find that you are past - the contents of B67, you have overflowed the segment. - - B67 also points to the stack segment linkage control - area, which is what we are really interested in. */ - - stkl = CRAY_STACKSEG_END (); - ssptr = (struct stack_segment_linkage *) stkl; - - /* If one subtracts 'size' from the end of the segment, - one has the address of the first word of the segment. - - If this is not the first segment, 'pseg' will be - nonzero. */ - - pseg = ssptr->sspseg; - size = ssptr->sssize; - - this_segment = stkl - size; - - /* It is possible that calling this routine itself caused - a stack overflow. Discard stack segments which do not - contain the target address. */ - - while (!(this_segment <= address && address <= stkl)) - { -# ifdef DEBUG_I00AFUNC - fprintf (stderr, "%011o %011o %011o\n", this_segment, address, stkl); -# endif - if (pseg == 0) - break; - stkl = stkl - pseg; - ssptr = (struct stack_segment_linkage *) stkl; - size = ssptr->sssize; - pseg = ssptr->sspseg; - this_segment = stkl - size; - } - - result = address - this_segment; - - /* If you subtract pseg from the current end of the stack, - you get the address of the previous stack segment's end. - This seems a little convoluted to me, but I'll bet you save - a cycle somewhere. */ - - while (pseg != 0) - { -# ifdef DEBUG_I00AFUNC - fprintf (stderr, "%011o %011o\n", pseg, size); -# endif - stkl = stkl - pseg; - ssptr = (struct stack_segment_linkage *) stkl; - size = ssptr->sssize; - pseg = ssptr->sspseg; - result += size; - } - return (result); -} - -# endif /* not CRAY2 */ -# endif /* CRAY */ - # endif /* no alloca */ -#endif /* not GCC 2 */ +#endif /* not GCC || clang */ |