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 "sbcl.h"
  21 #include "runtime.h"
  22 #include "os.h"
  23 #include "alloc.h"
  24 #include "globals.h"
  25 #include "gc.h"
  26 #include "thread.h"
  27 #include "genesis/vector.h"
  28 #include "genesis/cons.h"
  29 #include "genesis/bignum.h"
  30 #include "genesis/sap.h"
  31 #include "genesis/code.h"
  32
  33 #define ALIGNED_SIZE(n) ((n) + LOWTAG_MASK) & ~LOWTAG_MASK
  34
  35 #ifdef LISP_FEATURE_GENCGC
  36 extern lispobj *alloc(long bytes);
  37 #endif
  38
  39 static lispobj *
  40 pa_alloc(int bytes)
  41 {
  42     lispobj *result;
  43 #ifdef LISP_FEATURE_GENCGC
  44     struct thread *th = arch_os_get_current_thread();
  45
  46     /* FIXME: OOAO violation: see arch_pseudo_* */
  47     clear_pseudo_atomic_interrupted(th);
  48     set_pseudo_atomic_atomic(th);
  49     result = alloc(bytes);
  50     clear_pseudo_atomic_atomic(th);
  51
  52     if (get_pseudo_atomic_interrupted(th)) {
  53         /* WARNING KLUDGE FIXME: pa_alloc() is not pseudo-atomic on
  54          * anything but x86[-64]. maybe_defer_handler doesn't defer
  55          * interrupts if foreign_function_call_active
  56          *
  57          * If the C stack is not scavenged during GC, result needs to
  58          * be protected against not being referred to by any roots, so
  59          * we push it onto the lisp control stack, and read it back
  60          * off after any potential GC has finished */
  61 #ifndef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
  62 #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
  63 #error "!C_STACK_IS_CONTROL_STACK and STACK_GROWS_DOWNWARD_NOT_UPWARD is not supported"
  64 #endif
  65         *current_control_stack_pointer = (lispobj) result;
  66         current_control_stack_pointer += 1;
  67 #endif
  68         do_pending_interrupt();
  69 #ifndef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
  70         current_control_stack_pointer -= 1;
  71         result = (lispobj *) *current_control_stack_pointer;
  72 #endif
  73     }
  74 #else
  75     /* FIXME: this is not pseudo atomic at all, but is called only from
  76      * interrupt safe places like interrupt handlers. MG - 2005-08-09 */
  77     result = dynamic_space_free_pointer;
  78
  79     /* Align up to next dual word boundary. */
  80     bytes = ALIGNED_SIZE(bytes);
  81
  82     dynamic_space_free_pointer = (lispobj *)((char *)result + bytes);
  83
  84     if (current_auto_gc_trigger
  85         && dynamic_space_free_pointer > current_auto_gc_trigger) {
  86         clear_auto_gc_trigger();
  87         set_auto_gc_trigger((char *)dynamic_space_free_pointer
  88                             - (char *)current_dynamic_space);
  89     }
  90 #endif
  91     return result;
  92 }
  93
  94
  95 lispobj *
  96 alloc_unboxed(int type, int words)
  97 {
  98     lispobj *result;
  99
 100     result = pa_alloc(ALIGNED_SIZE((1 + words) * sizeof(lispobj)));
 101     *result = (lispobj) (words << N_WIDETAG_BITS) | type;
 102     return result;
 103 }
 104
 105 static lispobj
 106 alloc_vector(int type, int length, int size)
 107 {
 108     struct vector *result;
 109
 110     result = (struct vector *)
 111       pa_alloc(ALIGNED_SIZE((2 + (length*size + 31) / 32) * sizeof(lispobj)));
 112
 113     result->header = type;
 114     result->length = make_fixnum(length);
 115
 116     return make_lispobj(result,OTHER_POINTER_LOWTAG);
 117 }
 118
 119 lispobj
 120 alloc_cons(lispobj car, lispobj cdr)
 121 {
 122     struct cons *ptr =
 123         (struct cons *)pa_alloc(ALIGNED_SIZE(sizeof(struct cons)));
 124
 125     ptr->car = car;
 126     ptr->cdr = cdr;
 127
 128     return make_lispobj(ptr, LIST_POINTER_LOWTAG);
 129 }
 130
 131 lispobj
 132 alloc_number(long n)
 133 {
 134     struct bignum *ptr;
 135
 136     if (-0x20000000 < n && n < 0x20000000)
 137         return make_fixnum(n);
 138     else {
 139         ptr = (struct bignum *)alloc_unboxed(BIGNUM_WIDETAG, 1);
 140
 141         ptr->digits[0] = n;
 142
 143         return make_lispobj(ptr, OTHER_POINTER_LOWTAG);
 144     }
 145 }
 146
 147 lispobj
 148 alloc_base_string(char *str)
 149 {
 150     int len = strlen(str);
 151     lispobj result = alloc_vector(SIMPLE_BASE_STRING_WIDETAG, len+1, 8);
 152     struct vector *vec = (struct vector *)native_pointer(result);
 153
 154     vec->length = make_fixnum(len);
 155     strcpy((char *)vec->data, str);
 156
 157     return result;
 158 }
 159
 160 lispobj
 161 alloc_sap(void *ptr)
 162 {
 163     struct sap *sap;
 164     sap=(struct sap *)
 165         alloc_unboxed((int)SAP_WIDETAG, sizeof(struct sap)/sizeof(lispobj) -1);
 166     sap->pointer = ptr;
 167     return make_lispobj(sap,OTHER_POINTER_LOWTAG);
 168 }
 169
 170 lispobj
 171 alloc_code_object (unsigned boxed, unsigned unboxed) {
 172     struct code * code;
 173     unsigned size;
 174     boxed = make_fixnum(boxed + 1 + 4); /* 4 == trace_table_offset offset in words */
 175     boxed &= ~LOWTAG_MASK;
 176
 177     unboxed += LOWTAG_MASK;
 178     unboxed &= ~LOWTAG_MASK;
 179
 180     code = (struct code *) pa_alloc(ALIGNED_SIZE((boxed + unboxed) * sizeof(lispobj)));
 181
 182     boxed = boxed << (N_WIDETAG_BITS - WORD_SHIFT);
 183     code->header = boxed | CODE_HEADER_WIDETAG;
 184     code->code_size = unboxed;
 185     code->entry_points = NIL;
 186     code->debug_info = NIL;
 187     return make_lispobj(code, OTHER_POINTER_LOWTAG);
 188 }