1 ;;;; This file contains some parameterizations of various VM
2 ;;;; attributes for the x86. This file is separate from other stuff so
3 ;;;; that it can be compiled and loaded earlier.
5 ;;;; This software is part of the SBCL system. See the README file for
8 ;;;; This software is derived from the CMU CL system, which was
9 ;;;; written at Carnegie Mellon University and released into the
10 ;;;; public domain. The software is in the public domain and is
11 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
12 ;;;; files for more information.
16 ;;; ### Note: we simultaneously use ``word'' to mean a 32 bit quantity
17 ;;; and a 16 bit quantity depending on context. This is because Intel
18 ;;; insists on calling 16 bit things words and 32 bit things
19 ;;; double-words (or dwords). Therefore, in the instruction definition
20 ;;; and register specs, we use the Intel convention. But whenever we
21 ;;; are talking about stuff the rest of the lisp system might be
22 ;;; interested in, we use ``word'' to mean the size of a descriptor
23 ;;; object, which is 32 bits.
25 ;;;; machine architecture parameters
27 ;;; the number of bits per word, where a word holds one lisp descriptor
28 (def!constant n-word-bits 32)
30 ;;; the natural width of a machine word (as seen in e.g. register width,
32 (def!constant n-machine-word-bits 32)
34 ;;; the number of bits per byte, where a byte is the smallest
35 ;;; addressable object
36 (def!constant n-byte-bits 8)
38 ;;; The size in bytes of the GENCGC pages. Should be a multiple of the
39 ;;; architecture code size.
40 (def!constant gencgc-page-size 4096)
42 (def!constant float-sign-shift 31)
44 ;;; comment from CMU CL:
45 ;;; These values were taken from the alpha code. The values for
46 ;;; bias and exponent min/max are not the same as shown in the 486 book.
47 ;;; They may be correct for how Python uses them.
48 (def!constant single-float-bias 126) ; Intel says 127.
49 (defconstant-eqx single-float-exponent-byte (byte 8 23) #'equalp)
50 (defconstant-eqx single-float-significand-byte (byte 23 0) #'equalp)
51 ;;; comment from CMU CL:
52 ;;; The 486 book shows the exponent range -126 to +127. The Lisp
53 ;;; code that uses these values seems to want already biased numbers.
54 (def!constant single-float-normal-exponent-min 1)
55 (def!constant single-float-normal-exponent-max 254)
56 (def!constant single-float-hidden-bit (ash 1 23))
57 (def!constant single-float-trapping-nan-bit (ash 1 22))
59 (def!constant double-float-bias 1022)
60 (defconstant-eqx double-float-exponent-byte (byte 11 20) #'equalp)
61 (defconstant-eqx double-float-significand-byte (byte 20 0) #'equalp)
62 (def!constant double-float-normal-exponent-min 1)
63 (def!constant double-float-normal-exponent-max #x7FE)
64 (def!constant double-float-hidden-bit (ash 1 20))
65 (def!constant double-float-trapping-nan-bit (ash 1 19))
67 (def!constant long-float-bias 16382)
68 (defconstant-eqx long-float-exponent-byte (byte 15 0) #'equalp)
69 (defconstant-eqx long-float-significand-byte (byte 31 0) #'equalp)
70 (def!constant long-float-normal-exponent-min 1)
71 (def!constant long-float-normal-exponent-max #x7FFE)
72 (def!constant long-float-hidden-bit (ash 1 31)) ; actually not hidden
73 (def!constant long-float-trapping-nan-bit (ash 1 30))
75 (def!constant single-float-digits
76 (+ (byte-size single-float-significand-byte) 1))
78 (def!constant double-float-digits
79 (+ (byte-size double-float-significand-byte) n-word-bits 1))
81 (def!constant long-float-digits
82 (+ (byte-size long-float-significand-byte) n-word-bits 1))
84 ;;; pfw -- from i486 microprocessor programmer's reference manual
85 (def!constant float-invalid-trap-bit (ash 1 0))
86 (def!constant float-denormal-trap-bit (ash 1 1))
87 (def!constant float-divide-by-zero-trap-bit (ash 1 2))
88 (def!constant float-overflow-trap-bit (ash 1 3))
89 (def!constant float-underflow-trap-bit (ash 1 4))
90 (def!constant float-inexact-trap-bit (ash 1 5))
92 (def!constant float-round-to-nearest 0)
93 (def!constant float-round-to-negative 1)
94 (def!constant float-round-to-positive 2)
95 (def!constant float-round-to-zero 3)
97 (def!constant float-precision-24-bit 0)
98 (def!constant float-precision-53-bit 2)
99 (def!constant float-precision-64-bit 3)
101 (defconstant-eqx float-rounding-mode (byte 2 10) #'equalp)
102 (defconstant-eqx float-sticky-bits (byte 6 16) #'equalp)
103 (defconstant-eqx float-traps-byte (byte 6 0) #'equalp)
104 (defconstant-eqx float-exceptions-byte (byte 6 16) #'equalp)
105 (defconstant-eqx float-precision-control (byte 2 8) #'equalp)
106 (def!constant float-fast-bit 0) ; no fast mode on x86
108 ;;;; description of the target address space
110 ;;; where to put the different spaces
112 ;;; Note: Mostly these values are black magic, inherited from CMU CL
113 ;;; without any documentation. However, there were a few explanatory
114 ;;; comments in the CMU CL sources:
116 ;;; ** The space 0x08000000-0x10000000 is "C program and memory allocation".
117 ;;; ** The space 0x40000000-0x48000000 is reserved for shared libs.
118 ;;; ** The space >0xE0000000 is "C stack - Alien stack".
120 ;;; ** The space 0x0E000000-0x10000000 is "Foreign segment".
121 ;;; ** The space 0x20000000-0x30000000 is reserved for shared libs.
122 ;;; And there have been some changes since the fork from CMU CL:
123 ;;; * The OpenBSD port is new since the fork. We started with
124 ;;; the FreeBSD address map, which actually worked until the
125 ;;; Alpha port patches, for reasons which in retrospect are rather
126 ;;; mysterious. After the Alpha port patches were added, the
127 ;;; OpenBSD port suffered memory corruption problems. While
128 ;;; debugging those, it was discovered that src/runtime/trymap
129 ;;; failed for the control stack region #x40000000-#x47fff000.
130 ;;; After the control stack was moved upward out of this region
131 ;;; (stealing some bytes from dynamic space) the problems went
133 ;;; * The FreeBSD STATIC-SPACE-START value was bumped up from
134 ;;; #x28000000 to #x30000000 when FreeBSD ld.so dynamic linking
135 ;;; support was added for FreeBSD ca. 20000910. This was to keep from
136 ;;; stomping on an address range that the dynamic libraries want to
137 ;;; use. (They want to use this address range even if we try to
138 ;;; reserve it with a call to validate() as the first operation in
140 ;;; * For NetBSD 2.0, the following ranges are used by normal
141 ;;; executables and mmap:
142 ;;; ** Executables are (by default) loaded at 0x08048000.
143 ;;; ** The break for the sbcl runtime seems to end around 0x08400000
144 ;;; We set read only space around 0x20000000, static
145 ;;; space around 0x30000000, all ending below 0x37fff000
146 ;;; ** ld.so and other mmap'ed stuff like shared libs start around
148 ;;; We set dynamic space between 0x60000000 and 0x98000000
149 ;;; ** Bottom of the stack is typically not below 0xb0000000
150 ;;; FYI, this can be looked at with the "pmap" program, and if you
151 ;;; set the top-down mmap allocation option in the kernel (not yet
152 ;;; the default), all bets are totally off!
157 (def!constant read-only-space-start #x01000000)
158 (def!constant read-only-space-end #x037ff000)
160 (def!constant static-space-start #x05000000)
161 (def!constant static-space-end #x07fff000)
163 (def!constant dynamic-space-start #x09000000)
164 (def!constant dynamic-space-end #x29000000))
168 (def!constant read-only-space-start #x01000000)
169 (def!constant read-only-space-end #x037ff000)
171 (def!constant static-space-start #x05000000)
172 (def!constant static-space-end #x07fff000)
174 (def!constant dynamic-space-start #x09000000)
175 (def!constant dynamic-space-end #x29000000)
177 (def!constant linkage-table-space-start #x70000000)
178 (def!constant linkage-table-space-end #x7ffff000))
182 (def!constant read-only-space-start #x20000000)
183 (def!constant read-only-space-end #x2ffff000)
185 (def!constant static-space-start #x40000000)
186 (def!constant static-space-end #x42fff000)
188 (def!constant dynamic-space-start #x48000000)
189 (def!constant dynamic-space-end #xA0000000)
191 (def!constant linkage-table-space-start #xA2000000)
192 (def!constant linkage-table-space-end #xA3000000))
196 (def!constant read-only-space-start #x10000000)
197 (def!constant read-only-space-end #x1ffff000)
199 (def!constant static-space-start #x30000000)
200 (def!constant static-space-end #x37fff000)
202 (def!constant dynamic-space-start #x48000000)
203 (def!constant dynamic-space-end #x88000000)
205 ;; In CMUCL: 0xB0000000->0xB1000000
206 (def!constant linkage-table-space-start #x90000000)
207 (def!constant linkage-table-space-end #x91000000))
211 (def!constant read-only-space-start #x40000000)
212 (def!constant read-only-space-end #x47fff000)
214 (def!constant static-space-start #x50000000)
215 (def!constant static-space-end #x5ffff000)
217 (def!constant dynamic-space-start #x80000000)
218 (def!constant dynamic-space-end #xA0000000)
220 ;; In CMUCL: 0xB0000000->0xB1000000
221 (def!constant linkage-table-space-start #xA0000000)
222 (def!constant linkage-table-space-end #xA1000000))
226 (def!constant read-only-space-start #x20000000)
227 (def!constant read-only-space-end #x2ffff000)
229 (def!constant static-space-start #x30000000)
230 (def!constant static-space-end #x37fff000)
232 (def!constant dynamic-space-start #x60000000)
233 (def!constant dynamic-space-end #x98000000)
235 ;; In CMUCL: 0xB0000000->0xB1000000
236 (def!constant linkage-table-space-start #xA0000000)
237 (def!constant linkage-table-space-end #xA1000000))
239 ;;; Size of one linkage-table entry in bytes.
240 (def!constant linkage-table-entry-size 8)
242 ;;; Given that NIL is the first thing allocated in static space, we
243 ;;; know its value at compile time:
244 (def!constant nil-value (+ static-space-start #xb))
246 ;;;; other miscellaneous constants
248 (defenum (:suffix -trap :start 8)
255 single-step-breakpoint
256 #!+win32 context-restore) ;; HACK: The Win32 exception handling system does wrong things with this.
257 ;;; FIXME: It'd be nice to replace all the DEFENUMs with something like
258 ;;; (WITH-DEF-ENUM (:START 8)
259 ;;; (DEF-ENUM HALT-TRAP)
260 ;;; (DEF-ENUM PENDING-INTERRUPT-TRAP)
262 ;;; for the benefit of anyone doing a lexical search for definitions
263 ;;; of these symbols.
265 (defenum (:prefix object-not- :suffix -trap :start 16)
269 (defenum (:prefix trace-table-)
277 ;;; These symbols are loaded into static space directly after NIL so
278 ;;; that the system can compute their address by adding a constant
281 ;;; The fdefn objects for the static functions are loaded into static
282 ;;; space directly after the static symbols. That way, the raw-addr
283 ;;; can be loaded directly out of them by indirecting relative to NIL.
285 ;;; pfw X86 doesn't have enough registers to keep these things there.
286 ;;; Note these spaces grow from low to high addresses.
287 (defvar *allocation-pointer*)
288 (defvar *binding-stack-pointer*)
290 ;;; FIXME: !COLD-INIT probably doesn't need
291 ;;; to be in the static symbols table any more.
292 (defparameter *static-symbols*
295 ;; The C startup code must fill these in.
298 ;; functions that the C code needs to call. When adding to this list,
299 ;; also add a `frob' form in genesis.lisp finish-symbols.
301 sb!kernel::internal-error
302 sb!kernel::control-stack-exhausted-error
303 sb!kernel::undefined-alien-variable-error
304 sb!kernel::undefined-alien-function-error
305 sb!kernel::memory-fault-error
306 sb!di::handle-breakpoint
308 #!+win32 sb!kernel::handle-win32-exception
312 ;; Note that these are FIXNUM word counts, not (as one might
313 ;; expect) byte counts or SAPs. The reason seems to be that by
314 ;; representing them this way, we can avoid consing bignums.
316 *read-only-space-free-pointer*
317 *static-space-free-pointer*
318 *initial-dynamic-space-free-pointer*
320 ;; things needed for non-local exit
321 *current-catch-block*
322 *current-unwind-protect-block*
325 ;; interrupt handling
326 *pseudo-atomic-atomic*
327 *pseudo-atomic-interrupted*
328 sb!unix::*interrupts-enabled*
329 sb!unix::*interrupt-pending*
330 *free-interrupt-context-index*
332 #!+sb-thread *stop-for-gc-pending*
334 #!+sb-thread sb!thread::run-interruption
340 *binding-stack-pointer*
341 *binding-stack-start*
342 *control-stack-start*
345 ;; the floating point constants
350 ;; The following are all long-floats.
360 *restart-lisp-function*
362 ;; Needed for callbacks to work across saving cores. see
363 ;; ALIEN-CALLBACK-ASSEMBLER-WRAPPER in c-call.lisp for gory details.
364 sb!alien::*enter-alien-callback*
366 ;; The ..SLOT-UNBOUND.. symbol is static in order to optimise the
367 ;; common slot unbound check.
369 ;; FIXME: In SBCL, the CLOS code has become sufficiently tightly
370 ;; integrated into the system that it'd probably make sense to use
371 ;; the ordinary unbound marker for this.
372 sb!pcl::..slot-unbound..
375 (defparameter *static-funs*
386 sb!kernel:two-arg-and
387 sb!kernel:two-arg-ior
388 sb!kernel:two-arg-xor
389 sb!kernel:two-arg-gcd
390 sb!kernel:two-arg-lcm))
392 ;;;; stuff added by jrd
394 ;;; FIXME: Is this used? Delete it or document it.
395 ;;; cf the sparc PARMS.LISP
396 (defparameter *assembly-unit-length* 8)