src/runtime/alloc.c

   1 /*
   2  * allocation routines for C code.  For allocation done by Lisp look
   3  * instead at src/compiler/target/alloc.lisp and .../macros.lisp
   4  */
   5
   6 /*
   7  * This software is part of the SBCL system. See the README file for
   8  * more information.
   9  *
  10  * This software is derived from the CMU CL system, which was
  11  * written at Carnegie Mellon University and released into the
  12  * public domain. The software is in the public domain and is
  13  * provided with absolutely no warranty. See the COPYING and CREDITS
  14  * files for more information.
  15  */
  16
  17 #include <stdio.h>
  18 #include <string.h>
  19
  20 #include "runtime.h"
  21 #include "os.h"
  22 #include "sbcl.h"
  23 #include "alloc.h"
  24 #include "globals.h"
  25 #include "gc.h"
  26 #include "genesis/static-symbols.h"
  27 #include "genesis/vector.h"
  28 #include "genesis/cons.h"
  29 #include "genesis/bignum.h"
  30 #include "genesis/sap.h"
  31 #include "genesis/symbol.h"
  32
  33 #define GET_FREE_POINTER() dynamic_space_free_pointer
  34 #define SET_FREE_POINTER(new_value) \
  35     (dynamic_space_free_pointer = (new_value))
  36 #define GET_GC_TRIGGER() current_auto_gc_trigger
  37 #define SET_GC_TRIGGER(new_value) \
  38     clear_auto_gc_trigger(); set_auto_gc_trigger(new_value);
  39
  40 #define ALIGNED_SIZE(n) (n+LOWTAG_MASK) & ~LOWTAG_MASK
  41
  42 #if defined LISP_FEATURE_GENCGC
  43 extern lispobj *alloc(int bytes);
  44 lispobj *
  45 pa_alloc(int bytes)
  46 {
  47     lispobj *result=0;
  48     SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED, make_fixnum(0));
  49     SetSymbolValue(PSEUDO_ATOMIC_ATOMIC, make_fixnum(1));
  50     result=alloc(bytes);
  51     SetSymbolValue(PSEUDO_ATOMIC_ATOMIC, make_fixnum(0));
  52     if (SymbolValue(PSEUDO_ATOMIC_INTERRUPTED))
  53         /* even if we gc at this point, the new allocation will be
  54          * protected from being moved, because result is on the c stack
  55          * and points to it */
  56         do_pending_interrupt();
  57     return result;
  58 }
  59
  60 #else
  61 static lispobj *
  62 pa_alloc(int bytes)
  63 {
  64     char *result;
  65
  66     /* Round to dual word boundary. */
  67     bytes = (bytes + LOWTAG_MASK) & ~LOWTAG_MASK;
  68
  69     result = (char *)GET_FREE_POINTER();
  70
  71     SET_FREE_POINTER((lispobj *)(result + bytes));
  72
  73     if (GET_GC_TRIGGER() && GET_FREE_POINTER() > GET_GC_TRIGGER()) {
  74         SET_GC_TRIGGER((char *)GET_FREE_POINTER()
  75                        - (char *)current_dynamic_space);
  76     }
  77     return (lispobj *) result;
  78 }
  79 #endif
  80
  81
  82 lispobj *
  83 alloc_unboxed(int type, int words)
  84 {
  85     lispobj *result;
  86
  87     result = pa_alloc(ALIGNED_SIZE((1 + words) * sizeof(lispobj)));
  88     *result = (lispobj) (words << N_WIDETAG_BITS) | type;
  89     return result;
  90 }
  91
  92 static lispobj
  93 alloc_vector(int type, int length, int size)
  94 {
  95     struct vector *result;
  96
  97     result = (struct vector *)
  98       pa_alloc(ALIGNED_SIZE((2 + (length*size + 31) / 32) * sizeof(lispobj)));
  99
 100     result->header = type;
 101     result->length = make_fixnum(length);
 102
 103     return make_lispobj(result,OTHER_POINTER_LOWTAG);
 104 }
 105
 106 lispobj
 107 alloc_cons(lispobj car, lispobj cdr)
 108 {
 109     struct cons *ptr = (struct cons *)pa_alloc(ALIGNED_SIZE(sizeof(struct cons)));
 110
 111     ptr->car = car;
 112     ptr->cdr = cdr;
 113
 114     return make_lispobj(ptr, LIST_POINTER_LOWTAG);
 115 }
 116
 117 lispobj
 118 alloc_number(long n)
 119 {
 120     struct bignum *ptr;
 121
 122     if (-0x20000000 < n && n < 0x20000000)
 123         return make_fixnum(n);
 124     else {
 125         ptr = (struct bignum *)alloc_unboxed(BIGNUM_WIDETAG, 1);
 126
 127         ptr->digits[0] = n;
 128
 129         return make_lispobj(ptr, OTHER_POINTER_LOWTAG);
 130     }
 131 }
 132
 133 lispobj
 134 alloc_string(char *str)
 135 {
 136     int len = strlen(str);
 137     lispobj result = alloc_vector(SIMPLE_STRING_WIDETAG, len+1, 8);
 138     struct vector *vec = (struct vector *)native_pointer(result);
 139
 140     vec->length = make_fixnum(len);
 141     strcpy((char *)vec->data, str);
 142
 143     return result;
 144 }
 145
 146 lispobj
 147 alloc_sap(void *ptr)
 148 {
 149     struct sap *sap;
 150     sap=(struct sap *)
 151         alloc_unboxed((int)SAP_WIDETAG, sizeof(struct sap)/sizeof(lispobj) -1);
 152     sap->pointer = ptr;
 153     return make_lispobj(sap,OTHER_POINTER_LOWTAG);
 154 }