1 /* -----------------------------------------------------------------------------
2 * $Id: Regs.h,v 1.7 1999/11/09 15:57:39 simonmar Exp $
4 * (c) The GHC Team, 1998-1999
6 * Registers used in STG code. Might or might not correspond to
7 * actual machine registers.
9 * ---------------------------------------------------------------------------*/
15 * This file should do the right thing if we have no machine-registers
16 * defined, i.e. everything lives in the RegTable.
20 * This is the table that holds shadow-locations for all the STG
21 * registers. The shadow locations are used when:
23 * 1) the particular register isn't mapped to a real machine
24 * register, probably because there's a shortage of real registers.
25 * 2) caller-saves registers are saved across a CCall
28 typedef struct StgRegTable_ {
37 StgUnion rR9; /* used occasionally by heap/stack checks */
38 StgUnion rR10; /* used occasionally by heap/stack checks */
52 struct _bdescr *rNursery;
53 struct _bdescr *rCurrentNursery;
55 struct StgRegTable_ *link;
59 /* No such thing as a MainRegTable under SMP - each thread must
60 * have its own MainRegTable.
63 extern DLL_IMPORT_RTS StgRegTable MainRegTable;
69 * Registers Hp and HpLim are global across the entire system, and are
70 * copied into the RegTable before executing a thread.
72 * Registers Sp, Su, and SpLim are saved in the TSO for the
73 * thread, but are copied into the RegTable before executing a thread.
75 * All other registers are "general purpose", and are used for passing
76 * arguments to functions, and returning values. The code generator
77 * knows how many of these are in real registers, and avoids
78 * generating code that uses non-real registers. General purpose
79 * registers are never saved when returning to the scheduler, instead
80 * we save whatever is live at the time on the stack, and restore it
81 * later. This should reduce the context switch time, amongst other
84 * For argument passing, the stack will be used in preference to
85 * pseudo-registers if the architecture has too few general purpose
88 * Some special RTS functions like newArray and the Integer primitives
89 * expect their arguments to be in registers R1-Rn, so we use these
90 * (pseudo-)registers in those cases.
94 * Locations for saving per-thread registers.
97 #define SAVE_Sp (CurrentTSO->sp)
98 #define SAVE_Su (CurrentTSO->su)
99 #define SAVE_SpLim (CurrentTSO->splim)
101 #define SAVE_Hp (BaseReg->rHp)
102 #define SAVE_HpLim (BaseReg->rHpLim)
104 #define SAVE_CurrentTSO (BaseReg->rCurrentTSO)
105 #define SAVE_CurrentNursery (BaseReg->rCurrentNursery)
107 /* We sometimes need to save registers across a C-call, eg. if they
108 * are clobbered in the standard calling convention. We define the
109 * save locations for all registers in the register table.
112 #define SAVE_R1 (BaseReg->rR1)
113 #define SAVE_R2 (BaseReg->rR2)
114 #define SAVE_R3 (BaseReg->rR3)
115 #define SAVE_R4 (BaseReg->rR4)
116 #define SAVE_R5 (BaseReg->rR5)
117 #define SAVE_R6 (BaseReg->rR6)
118 #define SAVE_R7 (BaseReg->rR7)
119 #define SAVE_R8 (BaseReg->rR8)
121 #define SAVE_F1 (BaseReg->rF1)
122 #define SAVE_F2 (BaseReg->rF2)
123 #define SAVE_F3 (BaseReg->rF3)
124 #define SAVE_F4 (BaseReg->rF4)
126 #define SAVE_D1 (BaseReg->rD1)
127 #define SAVE_D2 (BaseReg->rD2)
129 #define SAVE_L1 (BaseReg->rL1)
131 /* -----------------------------------------------------------------------------
132 * Emit the GCC-specific register declarations for each machine
133 * register being used. If any STG register isn't mapped to a machine
134 * register, then map it to an offset from BaseReg.
136 * First, the general purpose registers. The idea is, if a particular
137 * general-purpose STG register can't be mapped to a real machine
138 * register, it won't be used at all. Instead, we'll use the stack.
140 * This is an improvement on the way things used to be done, when all
141 * registers were mapped to locations in the register table, and stuff
142 * was being shifted from the stack to the register table and back
143 * again for no good reason (on register-poor architectures).
146 #define GLOBAL_REG_DECL(type,name,reg) register type name REG(reg);
149 GLOBAL_REG_DECL(StgUnion,R1,REG_R1)
151 #define R1 (BaseReg->rR1)
155 GLOBAL_REG_DECL(StgUnion,R2,REG_R2)
157 #define R2 (BaseReg->rR2)
161 GLOBAL_REG_DECL(StgUnion,R3,REG_R3)
163 # define R3 (BaseReg->rR3)
167 GLOBAL_REG_DECL(StgUnion,R4,REG_R4)
169 # define R4 (BaseReg->rR4)
173 GLOBAL_REG_DECL(StgUnion,R5,REG_R5)
175 # define R5 (BaseReg->rR5)
179 GLOBAL_REG_DECL(StgUnion,R6,REG_R6)
181 # define R6 (BaseReg->rR6)
185 GLOBAL_REG_DECL(StgUnion,R7,REG_R7)
187 # define R7 (BaseReg->rR7)
191 GLOBAL_REG_DECL(StgUnion,R8,REG_R8)
193 # define R8 (BaseReg->rR8)
197 GLOBAL_REG_DECL(StgUnion,R9,REG_R9)
199 # define R9 (BaseReg->rR9)
203 GLOBAL_REG_DECL(StgUnion,R10,REG_R10)
205 # define R10 (BaseReg->rR10)
209 GLOBAL_REG_DECL(StgFloat,F1,REG_F1)
211 #define F1 (BaseReg->rF1)
215 GLOBAL_REG_DECL(StgFloat,F2,REG_F2)
217 #define F2 (BaseReg->rF2)
221 GLOBAL_REG_DECL(StgFloat,F3,REG_F3)
223 #define F3 (BaseReg->rF3)
227 GLOBAL_REG_DECL(StgFloat,F4,REG_F4)
229 #define F4 (BaseReg->rF4)
233 GLOBAL_REG_DECL(StgDouble,D1,REG_D1)
235 #define D1 (BaseReg->rD1)
239 GLOBAL_REG_DECL(StgDouble,D2,REG_D2)
241 #define D2 (BaseReg->rD2)
245 GLOBAL_REG_DECL(StgWord64,L1,REG_L1)
247 #define L1 (BaseReg->rL1)
251 * If BaseReg isn't mapped to a machine register, just use the global
252 * address of the current register table (CurrentRegTable in
253 * concurrent Haskell, MainRegTable otherwise).
257 GLOBAL_REG_DECL(StgRegTable *,BaseReg,REG_Base)
260 #error BaseReg must be in a register for SMP
262 #define BaseReg (&MainRegTable)
266 GLOBAL_REG_DECL(P_,Sp,REG_Sp)
268 #define Sp (BaseReg->rSp)
272 GLOBAL_REG_DECL(StgUpdateFrame *,Su,REG_Su)
274 #define Su (BaseReg->rSu)
278 GLOBAL_REG_DECL(P_,SpLim,REG_SpLim)
280 #define SpLim (BaseReg->rSpLim)
284 GLOBAL_REG_DECL(P_,Hp,REG_Hp)
286 #define Hp (BaseReg->rHp)
290 GLOBAL_REG_DECL(P_,HpLim,REG_HpLim)
292 #define HpLim (BaseReg->rHpLim)
295 #ifdef REG_CurrentTSO
296 GLOBAL_REG_DECL(StgTSO *,CurrentTSO,REG_CurrentTSO)
298 #define CurrentTSO (BaseReg->rCurrentTSO)
301 #ifdef REG_CurrentNursery
302 GLOBAL_REG_DECL(bdescr *,CurrentNursery,REG_CurrentNursery)
304 #define CurrentNursery (BaseReg->rCurrentNursery)
307 /* -----------------------------------------------------------------------------
308 For any registers which are denoted "caller-saves" by the C calling
309 convention, we have to emit code to save and restore them across C
311 -------------------------------------------------------------------------- */
313 #ifdef CALLER_SAVES_R1
314 #define CALLER_SAVE_R1 SAVE_R1 = R1;
315 #define CALLER_RESTORE_R1 R1 = SAVE_R1;
317 #define CALLER_SAVE_R1 /* nothing */
318 #define CALLER_RESTORE_R1 /* nothing */
321 #ifdef CALLER_SAVES_R2
322 #define CALLER_SAVE_R2 SAVE_R2 = R2;
323 #define CALLER_RESTORE_R2 R2 = SAVE_R2;
325 #define CALLER_SAVE_R2 /* nothing */
326 #define CALLER_RESTORE_R2 /* nothing */
329 #ifdef CALLER_SAVES_R3
330 #define CALLER_SAVE_R3 SAVE_R3 = R3;
331 #define CALLER_RESTORE_R3 R3 = SAVE_R3;
333 #define CALLER_SAVE_R3 /* nothing */
334 #define CALLER_RESTORE_R3 /* nothing */
337 #ifdef CALLER_SAVES_R4
338 #define CALLER_SAVE_R4 SAVE_R4 = R4;
339 #define CALLER_RESTORE_R4 R4 = SAVE_R4;
341 #define CALLER_SAVE_R4 /* nothing */
342 #define CALLER_RESTORE_R4 /* nothing */
345 #ifdef CALLER_SAVES_R5
346 #define CALLER_SAVE_R5 SAVE_R5 = R5;
347 #define CALLER_RESTORE_R5 R5 = SAVE_R5;
349 #define CALLER_SAVE_R5 /* nothing */
350 #define CALLER_RESTORE_R5 /* nothing */
353 #ifdef CALLER_SAVES_R6
354 #define CALLER_SAVE_R6 SAVE_R6 = R6;
355 #define CALLER_RESTORE_R6 R6 = SAVE_R6;
357 #define CALLER_SAVE_R6 /* nothing */
358 #define CALLER_RESTORE_R6 /* nothing */
361 #ifdef CALLER_SAVES_R7
362 #define CALLER_SAVE_R7 SAVE_R7 = R7;
363 #define CALLER_RESTORE_R7 R7 = SAVE_R7;
365 #define CALLER_SAVE_R7 /* nothing */
366 #define CALLER_RESTORE_R7 /* nothing */
369 #ifdef CALLER_SAVES_R8
370 #define CALLER_SAVE_R8 SAVE_R8 = R8;
371 #define CALLER_RESTORE_R8 R8 = SAVE_R8;
373 #define CALLER_SAVE_R8 /* nothing */
374 #define CALLER_RESTORE_R8 /* nothing */
377 #ifdef CALLER_SAVES_R9
378 #define CALLER_SAVE_R9 SAVE_R9 = R9;
379 #define CALLER_RESTORE_R9 R9 = SAVE_R9;
381 #define CALLER_SAVE_R9 /* nothing */
382 #define CALLER_RESTORE_R9 /* nothing */
385 #ifdef CALLER_SAVES_R10
386 #define CALLER_SAVE_R10 SAVE_R10 = R10;
387 #define CALLER_RESTORE_R10 R10 = SAVE_R10;
389 #define CALLER_SAVE_R10 /* nothing */
390 #define CALLER_RESTORE_R10 /* nothing */
393 #ifdef CALLER_SAVES_F1
394 #define CALLER_SAVE_F1 SAVE_F1 = F1;
395 #define CALLER_RESTORE_F1 F1 = SAVE_F1;
397 #define CALLER_SAVE_F1 /* nothing */
398 #define CALLER_RESTORE_F1 /* nothing */
401 #ifdef CALLER_SAVES_F2
402 #define CALLER_SAVE_F2 SAVE_F2 = F2;
403 #define CALLER_RESTORE_F2 F2 = SAVE_F2;
405 #define CALLER_SAVE_F2 /* nothing */
406 #define CALLER_RESTORE_F2 /* nothing */
409 #ifdef CALLER_SAVES_F3
410 #define CALLER_SAVE_F3 SAVE_F3 = F3;
411 #define CALLER_RESTORE_F3 F3 = SAVE_F3;
413 #define CALLER_SAVE_F3 /* nothing */
414 #define CALLER_RESTORE_F3 /* nothing */
417 #ifdef CALLER_SAVES_F4
418 #define CALLER_SAVE_F4 SAVE_F4 = F4;
419 #define CALLER_RESTORE_F4 F4 = SAVE_F4;
421 #define CALLER_SAVE_F4 /* nothing */
422 #define CALLER_RESTORE_F4 /* nothing */
425 #ifdef CALLER_SAVES_D1
426 #define CALLER_SAVE_D1 SAVE_D1 = D1;
427 #define CALLER_RESTORE_D1 D1 = SAVE_D1;
429 #define CALLER_SAVE_D1 /* nothing */
430 #define CALLER_RESTORE_D1 /* nothing */
433 #ifdef CALLER_SAVES_D2
434 #define CALLER_SAVE_D2 SAVE_D2 = D2;
435 #define CALLER_RESTORE_D2 D2 = SAVE_D2;
437 #define CALLER_SAVE_D2 /* nothing */
438 #define CALLER_RESTORE_D2 /* nothing */
441 #ifdef CALLER_SAVES_L1
442 #define CALLER_SAVE_L1 SAVE_L1 = L1;
443 #define CALLER_RESTORE_L1 L1 = SAVE_L1;
445 #define CALLER_SAVE_L1 /* nothing */
446 #define CALLER_RESTORE_L1 /* nothing */
449 #ifdef CALLER_SAVES_Sp
450 #define CALLER_SAVE_Sp SAVE_Sp = Sp;
451 #define CALLER_RESTORE_Sp Sp = SAVE_Sp;
453 #define CALLER_SAVE_Sp /* nothing */
454 #define CALLER_RESTORE_Sp /* nothing */
457 #ifdef CALLER_SAVES_Su
458 #define CALLER_SAVE_Su SAVE_Su = Su;
459 #define CALLER_RESTORE_Su Su = SAVE_Su;
461 #define CALLER_SAVE_Su /* nothing */
462 #define CALLER_RESTORE_Su /* nothing */
465 #ifdef CALLER_SAVES_SpLim
466 #define CALLER_SAVE_SpLim SAVE_SpLim = SpLim;
467 #define CALLER_RESTORE_SpLim SpLim = SAVE_SpLim;
469 #define CALLER_SAVE_SpLim /* nothing */
470 #define CALLER_RESTORE_SpLim /* nothing */
473 #ifdef CALLER_SAVES_Hp
474 #define CALLER_SAVE_Hp SAVE_Hp = Hp;
475 #define CALLER_RESTORE_Hp Hp = SAVE_Hp;
477 #define CALLER_SAVE_Hp /* nothing */
478 #define CALLER_RESTORE_Hp /* nothing */
481 #ifdef CALLER_SAVES_HpLim
482 #define CALLER_SAVE_HpLim SAVE_HpLim = HpLim;
483 #define CALLER_RESTORE_HpLim HpLim = SAVE_HpLim;
485 #define CALLER_SAVE_HpLim /* nothing */
486 #define CALLER_RESTORE_HpLim /* nothing */
489 #ifdef CALLER_SAVES_Base
491 #error "Can't have caller-saved BaseReg with SMP"
493 #define CALLER_SAVE_Base /* nothing */
494 #define CALLER_RESTORE_Base BaseReg = &MainRegTable;
496 #define CALLER_SAVE_Base /* nothing */
497 #define CALLER_RESTORE_Base /* nothing */
500 #ifdef CALLER_SAVES_CurrentTSO
501 #define CALLER_SAVE_CurrentTSO SAVE_CurrentTSO = CurrentTSO;
502 #define CALLER_RESTORE_CurrentTSO CurrentTSO = SAVE_CurrentTSO;
504 #define CALLER_SAVE_CurrentTSO /* nothing */
505 #define CALLER_RESTORE_CurrentTSO /* nothing */
508 #ifdef CALLER_SAVES_CurrentNursery
509 #define CALLER_SAVE_CurrentNursery SAVE_CurrentNursery = CurrentNursery;
510 #define CALLER_RESTORE_CurrentNursery CurrentNursery = SAVE_CurrentNursery;
512 #define CALLER_SAVE_CurrentNursery /* nothing */
513 #define CALLER_RESTORE_CurrentNursery /* nothing */
516 #endif /* IN_STG_CODE */
518 /* ----------------------------------------------------------------------------
519 Handy bunches of saves/restores
520 ------------------------------------------------------------------------ */
524 #define CALLER_SAVE_USER \
541 #define CALLER_SAVE_SYSTEM \
547 CALLER_SAVE_CurrentTSO \
548 CALLER_SAVE_CurrentNursery
550 #define CALLER_RESTORE_USER \
567 #define CALLER_RESTORE_SYSTEM \
568 CALLER_RESTORE_Base \
571 CALLER_RESTORE_SpLim \
573 CALLER_RESTORE_HpLim \
574 CALLER_RESTORE_CurrentTSO \
575 CALLER_RESTORE_CurrentNursery
577 #else /* not IN_STG_CODE */
579 #define CALLER_SAVE_USER /* nothing */
580 #define CALLER_SAVE_SYSTEM /* nothing */
581 #define CALLER_RESTORE_USER /* nothing */
582 #define CALLER_RESTORE_SYSTEM /* nothing */
584 #endif /* IN_STG_CODE */
586 #define CALLER_SAVE_ALL \
590 #define CALLER_RESTORE_ALL \
591 CALLER_RESTORE_SYSTEM \