1 /* -----------------------------------------------------------------------------
2 * $Id: Regs.h,v 1.3 1999/02/05 16:02:26 simonm 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
37 StgUnion rR9; /* used occasionally by heap/stack checks */
38 StgUnion rR10; /* used occasionally by heap/stack checks */
53 extern StgRegTable MainRegTable;
56 * Registers Hp and HpLim are global across the entire system, and are
57 * copied into the RegTable before executing a thread.
59 * Registers Sp, Su, and SpLim are saved in the TSO for the
60 * thread, but are copied into the RegTable before executing a thread.
62 * All other registers are "general purpose", and are used for passing
63 * arguments to functions, and returning values. The code generator
64 * knows how many of these are in real registers, and avoids
65 * generating code that uses non-real registers. General purpose
66 * registers are never saved when returning to the scheduler, instead
67 * we save whatever is live at the time on the stack, and restore it
68 * later. This should reduce the context switch time, amongst other
71 * For argument passing, the stack will be used in preference to
72 * pseudo-registers if the architecture has too few general purpose
75 * Some special RTS functions like newArray and the Integer primitives
76 * expect their arguments to be in registers R1-Rn, so we use these
77 * (pseudo-)registers in those cases.
81 * Locations for saving per-thread registers.
84 #define SAVE_Sp (CurrentTSO->sp)
85 #define SAVE_Su (CurrentTSO->su)
86 #define SAVE_SpLim (CurrentTSO->splim)
88 #define SAVE_Hp (MainRegTable.rHp)
89 #define SAVE_HpLim (MainRegTable.rHpLim)
91 /* We sometimes need to save registers across a C-call, eg. if they
92 * are clobbered in the standard calling convention. We define the
93 * save locations for all registers in the register table.
96 #define SAVE_R1 (MainRegTable.rR1)
97 #define SAVE_R2 (MainRegTable.rR2)
98 #define SAVE_R3 (MainRegTable.rR3)
99 #define SAVE_R4 (MainRegTable.rR4)
100 #define SAVE_R5 (MainRegTable.rR5)
101 #define SAVE_R6 (MainRegTable.rR6)
102 #define SAVE_R7 (MainRegTable.rR7)
103 #define SAVE_R8 (MainRegTable.rR8)
105 #define SAVE_F1 (MainRegTable.rF1)
106 #define SAVE_F2 (MainRegTable.rF2)
107 #define SAVE_F3 (MainRegTable.rF3)
108 #define SAVE_F4 (MainRegTable.rF4)
110 #define SAVE_D1 (MainRegTable.rD1)
111 #define SAVE_D2 (MainRegTable.rD2)
113 #define SAVE_L1 (MainRegTable.rL1)
115 /* -----------------------------------------------------------------------------
116 * Emit the GCC-specific register declarations for each machine
117 * register being used. If any STG register isn't mapped to a machine
118 * register, then map it to an offset from BaseReg.
120 * First, the general purpose registers. The idea is, if a particular
121 * general-purpose STG register can't be mapped to a real machine
122 * register, it won't be used at all. Instead, we'll use the stack.
124 * This is an improvement on the way things used to be done, when all
125 * registers were mapped to locations in the register table, and stuff
126 * was being shifted from the stack to the register table and back
127 * again for no good reason (on register-poor architectures).
130 #define GLOBAL_REG_DECL(type,name,reg) register type name REG(reg);
133 GLOBAL_REG_DECL(StgUnion,R1,REG_R1)
135 #define R1 (BaseReg->rR1)
139 GLOBAL_REG_DECL(StgUnion,R2,REG_R2)
141 #define R2 (BaseReg->rR2)
145 GLOBAL_REG_DECL(StgUnion,R3,REG_R3)
147 # define R3 (BaseReg->rR3)
151 GLOBAL_REG_DECL(StgUnion,R4,REG_R4)
153 # define R4 (BaseReg->rR4)
157 GLOBAL_REG_DECL(StgUnion,R5,REG_R5)
159 # define R5 (BaseReg->rR5)
163 GLOBAL_REG_DECL(StgUnion,R6,REG_R6)
165 # define R6 (BaseReg->rR6)
169 GLOBAL_REG_DECL(StgUnion,R7,REG_R7)
171 # define R7 (BaseReg->rR7)
175 GLOBAL_REG_DECL(StgUnion,R8,REG_R8)
177 # define R8 (BaseReg->rR8)
181 GLOBAL_REG_DECL(StgUnion,R9,REG_R9)
183 # define R9 (BaseReg->rR9)
187 GLOBAL_REG_DECL(StgUnion,R10,REG_R10)
189 # define R10 (BaseReg->rR10)
193 GLOBAL_REG_DECL(StgFloat,F1,REG_F1)
195 #define F1 (BaseReg->rF1)
199 GLOBAL_REG_DECL(StgFloat,F2,REG_F2)
201 #define F2 (BaseReg->rF2)
205 GLOBAL_REG_DECL(StgFloat,F3,REG_F3)
207 #define F3 (BaseReg->rF3)
211 GLOBAL_REG_DECL(StgFloat,F4,REG_F4)
213 #define F4 (BaseReg->rF4)
217 GLOBAL_REG_DECL(StgDouble,D1,REG_D1)
219 #define D1 (BaseReg->rD1)
223 GLOBAL_REG_DECL(StgDouble,D2,REG_D2)
225 #define D2 (BaseReg->rD2)
229 GLOBAL_REG_DECL(StgNat64,L1,REG_L1)
231 #define L1 (BaseReg->rL1)
235 * If BaseReg isn't mapped to a machine register, just use the global
236 * address of the current register table (CurrentRegTable in
237 * concurrent Haskell, MainRegTable otherwise).
241 GLOBAL_REG_DECL(StgRegTable *,BaseReg,REG_Base)
243 #define BaseReg (&MainRegTable)
247 GLOBAL_REG_DECL(P_,Sp,REG_Sp)
249 #define Sp (BaseReg->rSp)
253 GLOBAL_REG_DECL(StgUpdateFrame *,Su,REG_Su)
255 #define Su (BaseReg->rSu)
259 GLOBAL_REG_DECL(P_,SpLim,REG_SpLim)
261 #define SpLim (BaseReg->rSpLim)
265 GLOBAL_REG_DECL(P_,Hp,REG_Hp)
267 #define Hp (BaseReg->rHp)
271 GLOBAL_REG_DECL(P_,HpLim,REG_HpLim)
273 #define HpLim (BaseReg->rHpLim)
276 /* -----------------------------------------------------------------------------
277 For any registers which are denoted "caller-saves" by the C calling
278 convention, we have to emit code to save and restore them across C
280 -------------------------------------------------------------------------- */
282 #ifdef CALLER_SAVES_R1
283 #define CALLER_SAVE_R1 SAVE_R1 = R1;
284 #define CALLER_RESTORE_R1 R1 = SAVE_R1;
286 #define CALLER_SAVE_R1 /* nothing */
287 #define CALLER_RESTORE_R1 /* nothing */
290 #ifdef CALLER_SAVES_R2
291 #define CALLER_SAVE_R2 SAVE_R2 = R2;
292 #define CALLER_RESTORE_R2 R2 = SAVE_R2;
294 #define CALLER_SAVE_R2 /* nothing */
295 #define CALLER_RESTORE_R2 /* nothing */
298 #ifdef CALLER_SAVES_R3
299 #define CALLER_SAVE_R3 SAVE_R3 = R3;
300 #define CALLER_RESTORE_R3 R3 = SAVE_R3;
302 #define CALLER_SAVE_R3 /* nothing */
303 #define CALLER_RESTORE_R3 /* nothing */
306 #ifdef CALLER_SAVES_R4
307 #define CALLER_SAVE_R4 SAVE_R4 = R4;
308 #define CALLER_RESTORE_R4 R4 = SAVE_R4;
310 #define CALLER_SAVE_R4 /* nothing */
311 #define CALLER_RESTORE_R4 /* nothing */
314 #ifdef CALLER_SAVES_R5
315 #define CALLER_SAVE_R5 SAVE_R5 = R5;
316 #define CALLER_RESTORE_R5 R5 = SAVE_R5;
318 #define CALLER_SAVE_R5 /* nothing */
319 #define CALLER_RESTORE_R5 /* nothing */
322 #ifdef CALLER_SAVES_R6
323 #define CALLER_SAVE_R6 SAVE_R6 = R6;
324 #define CALLER_RESTORE_R6 R6 = SAVE_R6;
326 #define CALLER_SAVE_R6 /* nothing */
327 #define CALLER_RESTORE_R6 /* nothing */
330 #ifdef CALLER_SAVES_R7
331 #define CALLER_SAVE_R7 SAVE_R7 = R7;
332 #define CALLER_RESTORE_R7 R7 = SAVE_R7;
334 #define CALLER_SAVE_R7 /* nothing */
335 #define CALLER_RESTORE_R7 /* nothing */
338 #ifdef CALLER_SAVES_R8
339 #define CALLER_SAVE_R8 SAVE_R8 = R8;
340 #define CALLER_RESTORE_R8 R8 = SAVE_R8;
342 #define CALLER_SAVE_R8 /* nothing */
343 #define CALLER_RESTORE_R8 /* nothing */
346 #ifdef CALLER_SAVES_R9
347 #define CALLER_SAVE_R9 SAVE_R9 = R9;
348 #define CALLER_RESTORE_R9 R9 = SAVE_R9;
350 #define CALLER_SAVE_R9 /* nothing */
351 #define CALLER_RESTORE_R9 /* nothing */
354 #ifdef CALLER_SAVES_R10
355 #define CALLER_SAVE_R10 SAVE_R10 = R10;
356 #define CALLER_RESTORE_R10 R10 = SAVE_R10;
358 #define CALLER_SAVE_R10 /* nothing */
359 #define CALLER_RESTORE_R10 /* nothing */
362 #ifdef CALLER_SAVES_F1
363 #define CALLER_SAVE_F1 SAVE_F1 = F1;
364 #define CALLER_RESTORE_F1 F1 = SAVE_F1;
366 #define CALLER_SAVE_F1 /* nothing */
367 #define CALLER_RESTORE_F1 /* nothing */
370 #ifdef CALLER_SAVES_F2
371 #define CALLER_SAVE_F2 SAVE_F2 = F2;
372 #define CALLER_RESTORE_F2 F2 = SAVE_F2;
374 #define CALLER_SAVE_F2 /* nothing */
375 #define CALLER_RESTORE_F2 /* nothing */
378 #ifdef CALLER_SAVES_F3
379 #define CALLER_SAVE_F3 SAVE_F3 = F3;
380 #define CALLER_RESTORE_F3 F3 = SAVE_F3;
382 #define CALLER_SAVE_F3 /* nothing */
383 #define CALLER_RESTORE_F3 /* nothing */
386 #ifdef CALLER_SAVES_F4
387 #define CALLER_SAVE_F4 SAVE_F4 = F4;
388 #define CALLER_RESTORE_F4 F4 = SAVE_F4;
390 #define CALLER_SAVE_F4 /* nothing */
391 #define CALLER_RESTORE_F4 /* nothing */
394 #ifdef CALLER_SAVES_D1
395 #define CALLER_SAVE_D1 SAVE_D1 = D1;
396 #define CALLER_RESTORE_D1 D1 = SAVE_D1;
398 #define CALLER_SAVE_D1 /* nothing */
399 #define CALLER_RESTORE_D1 /* nothing */
402 #ifdef CALLER_SAVES_D2
403 #define CALLER_SAVE_D2 SAVE_D2 = D2;
404 #define CALLER_RESTORE_D2 D2 = SAVE_D2;
406 #define CALLER_SAVE_D2 /* nothing */
407 #define CALLER_RESTORE_D2 /* nothing */
410 #ifdef CALLER_SAVES_L1
411 #define CALLER_SAVE_L1 SAVE_L1 = L1;
412 #define CALLER_RESTORE_L1 L1 = SAVE_L1;
414 #define CALLER_SAVE_L1 /* nothing */
415 #define CALLER_RESTORE_L1 /* nothing */
418 #ifdef CALLER_SAVES_Sp
419 #define CALLER_SAVE_Sp SAVE_Sp = Sp;
420 #define CALLER_RESTORE_Sp Sp = SAVE_Sp;
422 #define CALLER_SAVE_Sp /* nothing */
423 #define CALLER_RESTORE_Sp /* nothing */
426 #ifdef CALLER_SAVES_Su
427 #define CALLER_SAVE_Su SAVE_Su = Su;
428 #define CALLER_RESTORE_Su Su = SAVE_Su;
430 #define CALLER_SAVE_Su /* nothing */
431 #define CALLER_RESTORE_Su /* nothing */
434 #ifdef CALLER_SAVES_SpLim
435 #define CALLER_SAVE_SpLim SAVE_SpLim = SpLim;
436 #define CALLER_RESTORE_SpLim SpLim = SAVE_SpLim;
438 #define CALLER_SAVE_SpLim /* nothing */
439 #define CALLER_RESTORE_SpLim /* nothing */
442 #ifdef CALLER_SAVES_Hp
443 #define CALLER_SAVE_Hp SAVE_Hp = Hp;
444 #define CALLER_RESTORE_Hp Hp = SAVE_Hp;
446 #define CALLER_SAVE_Hp /* nothing */
447 #define CALLER_RESTORE_Hp /* nothing */
450 #ifdef CALLER_SAVES_HpLim
451 #define CALLER_SAVE_HpLim SAVE_HpLim = HpLim;
452 #define CALLER_RESTORE_HpLim HpLim = SAVE_HpLim;
454 #define CALLER_SAVE_HpLim /* nothing */
455 #define CALLER_RESTORE_HpLim /* nothing */
458 #ifdef CALLER_SAVES_Base
459 #define CALLER_SAVE_Base /* nothing */
460 #define CALLER_RESTORE_Base BaseReg = &MainRegTable;
462 #define CALLER_SAVE_Base /* nothing */
463 #define CALLER_RESTORE_Base /* nothing */
466 /* ----------------------------------------------------------------------------
467 Handy bunches of saves/restores
468 ------------------------------------------------------------------------ */
470 #define CALLER_SAVE_USER \
487 #define CALLER_SAVE_SYSTEM \
494 #define CALLER_RESTORE_USER \
511 #define CALLER_RESTORE_SYSTEM \
512 CALLER_RESTORE_Base \
515 CALLER_RESTORE_SpLim \
519 #define CALLER_SAVE_ALL \
523 #define CALLER_RESTORE_ALL \
524 CALLER_RESTORE_SYSTEM \