2 ** FFI C call handling.
3 ** Copyright (C) 2005-2013 Mike Pall. See Copyright Notice in luajit.h
20 /* Target-specific handling of register arguments. */
22 /* -- x86 calling conventions --------------------------------------------- */
26 #define CCALL_HANDLE_STRUCTRET \
27 /* Return structs bigger than 8 by reference (on stack only). */ \
28 cc->retref = (sz > 8); \
29 if (cc->retref) cc->stack[nsp++] = (GPRArg)dp;
31 #define CCALL_HANDLE_COMPLEXRET CCALL_HANDLE_STRUCTRET
37 #define CCALL_HANDLE_STRUCTRET \
38 /* Return structs of size 1, 2, 4 or 8 in registers. */ \
39 cc->retref = !(sz == 1 || sz == 2 || sz == 4 || sz == 8); \
42 cc->gpr[ngpr++] = (GPRArg)dp; \
44 cc->stack[nsp++] = (GPRArg)dp; \
45 } else { /* Struct with single FP field ends up in FPR. */ \
46 cc->resx87 = ccall_classify_struct(cts, ctr); \
49 #define CCALL_HANDLE_STRUCTRET2 \
50 if (cc->resx87) sp = (uint8_t *)&cc->fpr[0]; \
51 memcpy(dp, sp, ctr->size);
55 #define CCALL_HANDLE_STRUCTRET \
56 cc->retref = 1; /* Return all structs by reference (in reg or on stack). */ \
58 cc->gpr[ngpr++] = (GPRArg)dp; \
60 cc->stack[nsp++] = (GPRArg)dp;
64 #define CCALL_HANDLE_COMPLEXRET \
65 /* Return complex float in GPRs and complex double by reference. */ \
66 cc->retref = (sz > 8); \
69 cc->gpr[ngpr++] = (GPRArg)dp; \
71 cc->stack[nsp++] = (GPRArg)dp; \
76 #define CCALL_HANDLE_COMPLEXRET2 \
78 *(int64_t *)dp = *(int64_t *)sp; /* Copy complex float from GPRs. */
80 #define CCALL_HANDLE_STRUCTARG \
81 ngpr = maxgpr; /* Pass all structs by value on the stack. */
83 #define CCALL_HANDLE_COMPLEXARG \
84 isfp = 1; /* Pass complex by value on stack. */
86 #define CCALL_HANDLE_REGARG \
87 if (!isfp) { /* Only non-FP values may be passed in registers. */ \
88 if (n > 1) { /* Anything > 32 bit is passed on the stack. */ \
89 if (!LJ_ABI_WIN) ngpr = maxgpr; /* Prevent reordering. */ \
90 } else if (ngpr + 1 <= maxgpr) { \
91 dp = &cc->gpr[ngpr]; \
97 #elif LJ_TARGET_X64 && LJ_ABI_WIN
98 /* -- Windows/x64 calling conventions ------------------------------------- */
100 #define CCALL_HANDLE_STRUCTRET \
101 /* Return structs of size 1, 2, 4 or 8 in a GPR. */ \
102 cc->retref = !(sz == 1 || sz == 2 || sz == 4 || sz == 8); \
103 if (cc->retref) cc->gpr[ngpr++] = (GPRArg)dp;
105 #define CCALL_HANDLE_COMPLEXRET CCALL_HANDLE_STRUCTRET
107 #define CCALL_HANDLE_COMPLEXRET2 \
109 *(int64_t *)dp = *(int64_t *)sp; /* Copy complex float from GPRs. */
111 #define CCALL_HANDLE_STRUCTARG \
112 /* Pass structs of size 1, 2, 4 or 8 in a GPR by value. */ \
113 if (!(sz == 1 || sz == 2 || sz == 4 || sz == 8)) { \
114 rp = cdataptr(lj_cdata_new(cts, did, sz)); \
115 sz = CTSIZE_PTR; /* Pass all other structs by reference. */ \
118 #define CCALL_HANDLE_COMPLEXARG \
119 /* Pass complex float in a GPR and complex double by reference. */ \
120 if (sz != 2*sizeof(float)) { \
121 rp = cdataptr(lj_cdata_new(cts, did, sz)); \
125 /* Windows/x64 argument registers are strictly positional (use ngpr). */
126 #define CCALL_HANDLE_REGARG \
128 if (ngpr < maxgpr) { dp = &cc->fpr[ngpr++]; nfpr = ngpr; goto done; } \
130 if (ngpr < maxgpr) { dp = &cc->gpr[ngpr++]; goto done; } \
134 /* -- POSIX/x64 calling conventions --------------------------------------- */
136 #define CCALL_HANDLE_STRUCTRET \
137 int rcl[2]; rcl[0] = rcl[1] = 0; \
138 if (ccall_classify_struct(cts, ctr, rcl, 0)) { \
139 cc->retref = 1; /* Return struct by reference. */ \
140 cc->gpr[ngpr++] = (GPRArg)dp; \
142 cc->retref = 0; /* Return small structs in registers. */ \
145 #define CCALL_HANDLE_STRUCTRET2 \
146 int rcl[2]; rcl[0] = rcl[1] = 0; \
147 ccall_classify_struct(cts, ctr, rcl, 0); \
148 ccall_struct_ret(cc, rcl, dp, ctr->size);
150 #define CCALL_HANDLE_COMPLEXRET \
151 /* Complex values are returned in one or two FPRs. */ \
154 #define CCALL_HANDLE_COMPLEXRET2 \
155 if (ctr->size == 2*sizeof(float)) { /* Copy complex float from FPR. */ \
156 *(int64_t *)dp = cc->fpr[0].l[0]; \
157 } else { /* Copy non-contiguous complex double from FPRs. */ \
158 ((int64_t *)dp)[0] = cc->fpr[0].l[0]; \
159 ((int64_t *)dp)[1] = cc->fpr[1].l[0]; \
162 #define CCALL_HANDLE_STRUCTARG \
163 int rcl[2]; rcl[0] = rcl[1] = 0; \
164 if (!ccall_classify_struct(cts, d, rcl, 0)) { \
165 cc->nsp = nsp; cc->ngpr = ngpr; cc->nfpr = nfpr; \
166 if (ccall_struct_arg(cc, cts, d, rcl, o, narg)) goto err_nyi; \
167 nsp = cc->nsp; ngpr = cc->ngpr; nfpr = cc->nfpr; \
169 } /* Pass all other structs by value on stack. */
171 #define CCALL_HANDLE_COMPLEXARG \
172 isfp = 2; /* Pass complex in FPRs or on stack. Needs postprocessing. */
174 #define CCALL_HANDLE_REGARG \
175 if (isfp) { /* Try to pass argument in FPRs. */ \
176 int n2 = ctype_isvector(d->info) ? 1 : n; \
177 if (nfpr + n2 <= CCALL_NARG_FPR) { \
178 dp = &cc->fpr[nfpr]; \
182 } else { /* Try to pass argument in GPRs. */ \
183 /* Note that reordering is explicitly allowed in the x64 ABI. */ \
184 if (n <= 2 && ngpr + n <= maxgpr) { \
185 dp = &cc->gpr[ngpr]; \
192 /* -- ARM calling conventions --------------------------------------------- */
196 #define CCALL_HANDLE_STRUCTRET \
197 /* Return structs of size <= 4 in a GPR. */ \
198 cc->retref = !(sz <= 4); \
199 if (cc->retref) cc->gpr[ngpr++] = (GPRArg)dp;
201 #define CCALL_HANDLE_COMPLEXRET \
202 cc->retref = 1; /* Return all complex values by reference. */ \
203 cc->gpr[ngpr++] = (GPRArg)dp;
205 #define CCALL_HANDLE_COMPLEXRET2 \
206 UNUSED(dp); /* Nothing to do. */
208 #define CCALL_HANDLE_STRUCTARG \
209 /* Pass all structs by value in registers and/or on the stack. */
211 #define CCALL_HANDLE_COMPLEXARG \
212 /* Pass complex by value in 2 or 4 GPRs. */
214 #define CCALL_HANDLE_REGARG_FP1
215 #define CCALL_HANDLE_REGARG_FP2
219 #define CCALL_HANDLE_STRUCTRET \
220 cc->retref = !ccall_classify_struct(cts, ctr, ct); \
221 if (cc->retref) cc->gpr[ngpr++] = (GPRArg)dp;
223 #define CCALL_HANDLE_STRUCTRET2 \
224 if (ccall_classify_struct(cts, ctr, ct) > 1) sp = (uint8_t *)&cc->fpr[0]; \
225 memcpy(dp, sp, ctr->size);
227 #define CCALL_HANDLE_COMPLEXRET \
228 if (!(ct->info & CTF_VARARG)) cc->retref = 0; /* Return complex in FPRs. */
230 #define CCALL_HANDLE_COMPLEXRET2 \
231 if (!(ct->info & CTF_VARARG)) memcpy(dp, &cc->fpr[0], ctr->size);
233 #define CCALL_HANDLE_STRUCTARG \
234 isfp = (ccall_classify_struct(cts, d, ct) > 1);
235 /* Pass all structs by value in registers and/or on the stack. */
237 #define CCALL_HANDLE_COMPLEXARG \
238 isfp = 1; /* Pass complex by value in FPRs or on stack. */
240 #define CCALL_HANDLE_REGARG_FP1 \
241 if (isfp && !(ct->info & CTF_VARARG)) { \
242 if ((d->info & CTF_ALIGN) > CTALIGN_PTR) { \
243 if (nfpr + (n >> 1) <= CCALL_NARG_FPR) { \
244 dp = &cc->fpr[nfpr]; \
249 if (sz > 1 && fprodd != nfpr) fprodd = 0; \
251 if (2*nfpr+n <= 2*CCALL_NARG_FPR+1) { \
252 dp = (void *)&cc->fpr[fprodd-1].f[1]; \
254 if ((n & 1)) fprodd = 0; else fprodd = nfpr-1; \
258 if (2*nfpr+n <= 2*CCALL_NARG_FPR) { \
259 dp = (void *)&cc->fpr[nfpr]; \
261 if ((n & 1)) fprodd = ++nfpr; else fprodd = 0; \
266 fprodd = 0; /* No reordering after the first FP value is on stack. */ \
269 #define CCALL_HANDLE_REGARG_FP2 }
273 #define CCALL_HANDLE_REGARG \
274 CCALL_HANDLE_REGARG_FP1 \
275 if ((d->info & CTF_ALIGN) > CTALIGN_PTR) { \
277 ngpr = (ngpr + 1u) & ~1u; /* Align to regpair. */ \
279 if (ngpr < maxgpr) { \
280 dp = &cc->gpr[ngpr]; \
281 if (ngpr + n > maxgpr) { \
282 nsp += ngpr + n - maxgpr; /* Assumes contiguous gpr/stack fields. */ \
283 if (nsp > CCALL_MAXSTACK) goto err_nyi; /* Too many arguments. */ \
289 } CCALL_HANDLE_REGARG_FP2
291 #define CCALL_HANDLE_RET \
292 if ((ct->info & CTF_VARARG)) sp = (uint8_t *)&cc->gpr[0];
295 /* -- PPC calling conventions --------------------------------------------- */
297 #define CCALL_HANDLE_STRUCTRET \
298 cc->retref = 1; /* Return all structs by reference. */ \
299 cc->gpr[ngpr++] = (GPRArg)dp;
301 #define CCALL_HANDLE_COMPLEXRET \
302 /* Complex values are returned in 2 or 4 GPRs. */ \
305 #define CCALL_HANDLE_COMPLEXRET2 \
306 memcpy(dp, sp, ctr->size); /* Copy complex from GPRs. */
308 #define CCALL_HANDLE_STRUCTARG \
309 rp = cdataptr(lj_cdata_new(cts, did, sz)); \
310 sz = CTSIZE_PTR; /* Pass all structs by reference. */
312 #define CCALL_HANDLE_COMPLEXARG \
313 /* Pass complex by value in 2 or 4 GPRs. */
315 #define CCALL_HANDLE_REGARG \
316 if (isfp) { /* Try to pass argument in FPRs. */ \
317 if (nfpr + 1 <= CCALL_NARG_FPR) { \
318 dp = &cc->fpr[nfpr]; \
320 d = ctype_get(cts, CTID_DOUBLE); /* FPRs always hold doubles. */ \
323 } else { /* Try to pass argument in GPRs. */ \
325 lua_assert(n == 2 || n == 4); /* int64_t or complex (float). */ \
326 if (ctype_isinteger(d->info)) \
327 ngpr = (ngpr + 1u) & ~1u; /* Align int64_t to regpair. */ \
328 else if (ngpr + n > maxgpr) \
329 ngpr = maxgpr; /* Prevent reordering. */ \
331 if (ngpr + n <= maxgpr) { \
332 dp = &cc->gpr[ngpr]; \
338 #define CCALL_HANDLE_RET \
339 if (ctype_isfp(ctr->info) && ctr->size == sizeof(float)) \
340 ctr = ctype_get(cts, CTID_DOUBLE); /* FPRs always hold doubles. */
342 #elif LJ_TARGET_PPCSPE
343 /* -- PPC/SPE calling conventions ----------------------------------------- */
345 #define CCALL_HANDLE_STRUCTRET \
346 cc->retref = 1; /* Return all structs by reference. */ \
347 cc->gpr[ngpr++] = (GPRArg)dp;
349 #define CCALL_HANDLE_COMPLEXRET \
350 /* Complex values are returned in 2 or 4 GPRs. */ \
353 #define CCALL_HANDLE_COMPLEXRET2 \
354 memcpy(dp, sp, ctr->size); /* Copy complex from GPRs. */
356 #define CCALL_HANDLE_STRUCTARG \
357 rp = cdataptr(lj_cdata_new(cts, did, sz)); \
358 sz = CTSIZE_PTR; /* Pass all structs by reference. */
360 #define CCALL_HANDLE_COMPLEXARG \
361 /* Pass complex by value in 2 or 4 GPRs. */
363 /* PPC/SPE has a softfp ABI. */
364 #define CCALL_HANDLE_REGARG \
365 if (n > 1) { /* Doesn't fit in a single GPR? */ \
366 lua_assert(n == 2 || n == 4); /* int64_t, double or complex (float). */ \
368 ngpr = (ngpr + 1u) & ~1u; /* Only align 64 bit value to regpair. */ \
369 else if (ngpr + n > maxgpr) \
370 ngpr = maxgpr; /* Prevent reordering. */ \
372 if (ngpr + n <= maxgpr) { \
373 dp = &cc->gpr[ngpr]; \
379 /* -- MIPS calling conventions -------------------------------------------- */
381 #define CCALL_HANDLE_STRUCTRET \
382 cc->retref = 1; /* Return all structs by reference. */ \
383 cc->gpr[ngpr++] = (GPRArg)dp;
385 #define CCALL_HANDLE_COMPLEXRET \
386 /* Complex values are returned in 1 or 2 FPRs. */ \
389 #define CCALL_HANDLE_COMPLEXRET2 \
390 if (ctr->size == 2*sizeof(float)) { /* Copy complex float from FPRs. */ \
391 ((float *)dp)[0] = cc->fpr[0].f; \
392 ((float *)dp)[1] = cc->fpr[1].f; \
393 } else { /* Copy complex double from FPRs. */ \
394 ((double *)dp)[0] = cc->fpr[0].d; \
395 ((double *)dp)[1] = cc->fpr[1].d; \
398 #define CCALL_HANDLE_STRUCTARG \
399 /* Pass all structs by value in registers and/or on the stack. */
401 #define CCALL_HANDLE_COMPLEXARG \
402 /* Pass complex by value in 2 or 4 GPRs. */
404 #define CCALL_HANDLE_REGARG \
405 if (isfp && nfpr < CCALL_NARG_FPR && !(ct->info & CTF_VARARG)) { \
406 /* Try to pass argument in FPRs. */ \
407 dp = n == 1 ? (void *)&cc->fpr[nfpr].f : (void *)&cc->fpr[nfpr].d; \
410 } else { /* Try to pass argument in GPRs. */ \
411 nfpr = CCALL_NARG_FPR; \
412 if ((d->info & CTF_ALIGN) > CTALIGN_PTR) \
413 ngpr = (ngpr + 1u) & ~1u; /* Align to regpair. */ \
414 if (ngpr < maxgpr) { \
415 dp = &cc->gpr[ngpr]; \
416 if (ngpr + n > maxgpr) { \
417 nsp += ngpr + n - maxgpr; /* Assumes contiguous gpr/stack fields. */ \
418 if (nsp > CCALL_MAXSTACK) goto err_nyi; /* Too many arguments. */ \
427 #define CCALL_HANDLE_RET \
428 if (ctype_isfp(ctr->info) && ctr->size == sizeof(float)) \
429 sp = (uint8_t *)&cc->fpr[0].f;
432 #error "Missing calling convention definitions for this architecture"
435 #ifndef CCALL_HANDLE_STRUCTRET2
436 #define CCALL_HANDLE_STRUCTRET2 \
437 memcpy(dp, sp, ctr->size); /* Copy struct return value from GPRs. */
440 /* -- x86 OSX ABI struct classification ----------------------------------- */
442 #if LJ_TARGET_X86 && LJ_TARGET_OSX
444 /* Check for struct with single FP field. */
445 static int ccall_classify_struct(CTState
*cts
, CType
*ct
)
447 CTSize sz
= ct
->size
;
448 if (!(sz
== sizeof(float) || sz
== sizeof(double))) return 0;
449 if ((ct
->info
& CTF_UNION
)) return 0;
451 ct
= ctype_get(cts
, ct
->sib
);
452 if (ctype_isfield(ct
->info
)) {
453 CType
*sct
= ctype_rawchild(cts
, ct
);
454 if (ctype_isfp(sct
->info
)) {
456 return (sz
>> 2); /* Return 1 for float or 2 for double. */
457 } else if (ctype_isstruct(sct
->info
)) {
459 return ccall_classify_struct(cts
, sct
);
463 } else if (ctype_isbitfield(ct
->info
)) {
465 } else if (ctype_isxattrib(ct
->info
, CTA_SUBTYPE
)) {
466 CType
*sct
= ctype_rawchild(cts
, ct
);
468 return ccall_classify_struct(cts
, sct
);
476 /* -- x64 struct classification ------------------------------------------- */
478 #if LJ_TARGET_X64 && !LJ_ABI_WIN
480 /* Register classes for x64 struct classification. */
481 #define CCALL_RCL_INT 1
482 #define CCALL_RCL_SSE 2
483 #define CCALL_RCL_MEM 4
484 /* NYI: classify vectors. */
486 static int ccall_classify_struct(CTState
*cts
, CType
*ct
, int *rcl
, CTSize ofs
);
488 /* Classify a C type. */
489 static void ccall_classify_ct(CTState
*cts
, CType
*ct
, int *rcl
, CTSize ofs
)
491 if (ctype_isarray(ct
->info
)) {
492 CType
*cct
= ctype_rawchild(cts
, ct
);
493 CTSize eofs
, esz
= cct
->size
, asz
= ct
->size
;
494 for (eofs
= 0; eofs
< asz
; eofs
+= esz
)
495 ccall_classify_ct(cts
, cct
, rcl
, ofs
+eofs
);
496 } else if (ctype_isstruct(ct
->info
)) {
497 ccall_classify_struct(cts
, ct
, rcl
, ofs
);
499 int cl
= ctype_isfp(ct
->info
) ? CCALL_RCL_SSE
: CCALL_RCL_INT
;
500 lua_assert(ctype_hassize(ct
->info
));
501 if ((ofs
& (ct
->size
-1))) cl
= CCALL_RCL_MEM
; /* Unaligned. */
502 rcl
[(ofs
>= 8)] |= cl
;
506 /* Recursively classify a struct based on its fields. */
507 static int ccall_classify_struct(CTState
*cts
, CType
*ct
, int *rcl
, CTSize ofs
)
509 if (ct
->size
> 16) return CCALL_RCL_MEM
; /* Too big, gets memory class. */
512 ct
= ctype_get(cts
, ct
->sib
);
514 if (ctype_isfield(ct
->info
))
515 ccall_classify_ct(cts
, ctype_rawchild(cts
, ct
), rcl
, fofs
);
516 else if (ctype_isbitfield(ct
->info
))
517 rcl
[(fofs
>= 8)] |= CCALL_RCL_INT
; /* NYI: unaligned bitfields? */
518 else if (ctype_isxattrib(ct
->info
, CTA_SUBTYPE
))
519 ccall_classify_struct(cts
, ctype_rawchild(cts
, ct
), rcl
, fofs
);
521 return ((rcl
[0]|rcl
[1]) & CCALL_RCL_MEM
); /* Memory class? */
524 /* Try to split up a small struct into registers. */
525 static int ccall_struct_reg(CCallState
*cc
, GPRArg
*dp
, int *rcl
)
527 MSize ngpr
= cc
->ngpr
, nfpr
= cc
->nfpr
;
529 for (i
= 0; i
< 2; i
++) {
530 lua_assert(!(rcl
[i
] & CCALL_RCL_MEM
));
531 if ((rcl
[i
] & CCALL_RCL_INT
)) { /* Integer class takes precedence. */
532 if (ngpr
>= CCALL_NARG_GPR
) return 1; /* Register overflow. */
533 cc
->gpr
[ngpr
++] = dp
[i
];
534 } else if ((rcl
[i
] & CCALL_RCL_SSE
)) {
535 if (nfpr
>= CCALL_NARG_FPR
) return 1; /* Register overflow. */
536 cc
->fpr
[nfpr
++].l
[0] = dp
[i
];
539 cc
->ngpr
= ngpr
; cc
->nfpr
= nfpr
;
543 /* Pass a small struct argument. */
544 static int ccall_struct_arg(CCallState
*cc
, CTState
*cts
, CType
*d
, int *rcl
,
549 /* Convert to temp. struct. */
550 lj_cconv_ct_tv(cts
, d
, (uint8_t *)dp
, o
, CCF_ARG(narg
));
551 if (ccall_struct_reg(cc
, dp
, rcl
)) { /* Register overflow? Pass on stack. */
552 MSize nsp
= cc
->nsp
, n
= rcl
[1] ? 2 : 1;
553 if (nsp
+ n
> CCALL_MAXSTACK
) return 1; /* Too many arguments. */
555 memcpy(&cc
->stack
[nsp
], dp
, n
*CTSIZE_PTR
);
560 /* Combine returned small struct. */
561 static void ccall_struct_ret(CCallState
*cc
, int *rcl
, uint8_t *dp
, CTSize sz
)
564 MSize ngpr
= 0, nfpr
= 0;
566 for (i
= 0; i
< 2; i
++) {
567 if ((rcl
[i
] & CCALL_RCL_INT
)) { /* Integer class takes precedence. */
568 sp
[i
] = cc
->gpr
[ngpr
++];
569 } else if ((rcl
[i
] & CCALL_RCL_SSE
)) {
570 sp
[i
] = cc
->fpr
[nfpr
++].l
[0];
577 /* -- ARM hard-float ABI struct classification ---------------------------- */
579 #if LJ_TARGET_ARM && !LJ_ABI_SOFTFP
581 /* Classify a struct based on its fields. */
582 static unsigned int ccall_classify_struct(CTState
*cts
, CType
*ct
, CType
*ctf
)
584 CTSize sz
= ct
->size
;
585 unsigned int r
= 0, n
= 0, isu
= (ct
->info
& CTF_UNION
);
586 if ((ctf
->info
& CTF_VARARG
)) goto noth
;
589 ct
= ctype_get(cts
, ct
->sib
);
590 if (ctype_isfield(ct
->info
)) {
591 sct
= ctype_rawchild(cts
, ct
);
592 if (ctype_isfp(sct
->info
)) {
594 if (!isu
) n
++; else if (n
== 0) n
= 1;
595 } else if (ctype_iscomplex(sct
->info
)) {
596 r
|= (sct
->size
>> 1);
597 if (!isu
) n
+= 2; else if (n
< 2) n
= 2;
598 } else if (ctype_isstruct(sct
->info
)) {
603 } else if (ctype_isbitfield(ct
->info
)) {
605 } else if (ctype_isxattrib(ct
->info
, CTA_SUBTYPE
)) {
606 sct
= ctype_rawchild(cts
, ct
);
609 unsigned int s
= ccall_classify_struct(cts
, sct
, ctf
);
610 if (s
<= 1) goto noth
;
612 if (!isu
) n
+= (s
>> 8); else if (n
< (s
>>8)) n
= (s
>> 8);
616 if ((r
== 4 || r
== 8) && n
<= 4)
618 noth
: /* Not a homogeneous float/double aggregate. */
619 return (sz
<= 4); /* Return structs of size <= 4 in a GPR. */
624 /* -- Common C call handling ---------------------------------------------- */
626 /* Infer the destination CTypeID for a vararg argument. */
627 CTypeID
lj_ccall_ctid_vararg(CTState
*cts
, cTValue
*o
)
631 } else if (tviscdata(o
)) {
632 CTypeID id
= cdataV(o
)->ctypeid
;
633 CType
*s
= ctype_get(cts
, id
);
634 if (ctype_isrefarray(s
->info
)) {
635 return lj_ctype_intern(cts
,
636 CTINFO(CT_PTR
, CTALIGN_PTR
|ctype_cid(s
->info
)), CTSIZE_PTR
);
637 } else if (ctype_isstruct(s
->info
) || ctype_isfunc(s
->info
)) {
638 /* NYI: how to pass a struct by value in a vararg argument? */
639 return lj_ctype_intern(cts
, CTINFO(CT_PTR
, CTALIGN_PTR
|id
), CTSIZE_PTR
);
640 } else if (ctype_isfp(s
->info
) && s
->size
== sizeof(float)) {
645 } else if (tvisstr(o
)) {
647 } else if (tvisbool(o
)) {
654 /* Setup arguments for C call. */
655 static int ccall_set_args(lua_State
*L
, CTState
*cts
, CType
*ct
,
659 TValue
*o
, *top
= L
->top
;
662 MSize maxgpr
, ngpr
= 0, nsp
= 0, narg
;
670 /* Clear unused regs to get some determinism in case of misdeclaration. */
671 memset(cc
->gpr
, 0, sizeof(cc
->gpr
));
673 memset(cc
->fpr
, 0, sizeof(cc
->fpr
));
677 /* x86 has several different calling conventions. */
679 switch (ctype_cconv(ct
->info
)) {
680 case CTCC_FASTCALL
: maxgpr
= 2; break;
681 case CTCC_THISCALL
: maxgpr
= 1; break;
682 default: maxgpr
= 0; break;
685 maxgpr
= CCALL_NARG_GPR
;
688 /* Perform required setup for some result types. */
689 ctr
= ctype_rawchild(cts
, ct
);
690 if (ctype_isvector(ctr
->info
)) {
691 if (!(CCALL_VECTOR_REG
&& (ctr
->size
== 8 || ctr
->size
== 16)))
693 } else if (ctype_iscomplex(ctr
->info
) || ctype_isstruct(ctr
->info
)) {
694 /* Preallocate cdata object and anchor it after arguments. */
695 CTSize sz
= ctr
->size
;
696 GCcdata
*cd
= lj_cdata_new(cts
, ctype_cid(ct
->info
), sz
);
697 void *dp
= cdataptr(cd
);
698 setcdataV(L
, L
->top
++, cd
);
699 if (ctype_isstruct(ctr
->info
)) {
700 CCALL_HANDLE_STRUCTRET
702 CCALL_HANDLE_COMPLEXRET
705 } else if (ctype_isfp(ctr
->info
)) {
706 cc
->resx87
= ctr
->size
== sizeof(float) ? 1 : 2;
710 /* Skip initial attributes. */
713 CType
*ctf
= ctype_get(cts
, fid
);
714 if (!ctype_isattrib(ctf
->info
)) break;
718 /* Walk through all passed arguments. */
719 for (o
= L
->base
+1, narg
= 1; o
< top
; o
++, narg
++) {
723 MSize n
, isfp
= 0, isva
= 0;
724 void *dp
, *rp
= NULL
;
726 if (fid
) { /* Get argument type from field. */
727 CType
*ctf
= ctype_get(cts
, fid
);
729 lua_assert(ctype_isfield(ctf
->info
));
730 did
= ctype_cid(ctf
->info
);
732 if (!(ct
->info
& CTF_VARARG
))
733 lj_err_caller(L
, LJ_ERR_FFI_NUMARG
); /* Too many arguments. */
734 did
= lj_ccall_ctid_vararg(cts
, o
); /* Infer vararg type. */
737 d
= ctype_raw(cts
, did
);
740 /* Find out how (by value/ref) and where (GPR/FPR) to pass an argument. */
741 if (ctype_isnum(d
->info
)) {
742 if (sz
> 8) goto err_nyi
;
743 if ((d
->info
& CTF_FP
))
745 } else if (ctype_isvector(d
->info
)) {
746 if (CCALL_VECTOR_REG
&& (sz
== 8 || sz
== 16))
750 } else if (ctype_isstruct(d
->info
)) {
751 CCALL_HANDLE_STRUCTARG
752 } else if (ctype_iscomplex(d
->info
)) {
753 CCALL_HANDLE_COMPLEXARG
757 sz
= (sz
+ CTSIZE_PTR
-1) & ~(CTSIZE_PTR
-1);
758 n
= sz
/ CTSIZE_PTR
; /* Number of GPRs or stack slots needed. */
760 CCALL_HANDLE_REGARG
/* Handle register arguments. */
762 /* Otherwise pass argument on stack. */
763 if (CCALL_ALIGN_STACKARG
&& !rp
&& (d
->info
& CTF_ALIGN
) > CTALIGN_PTR
) {
764 MSize align
= (1u << ctype_align(d
->info
-CTALIGN_PTR
)) -1;
765 nsp
= (nsp
+ align
) & ~align
; /* Align argument on stack. */
767 if (nsp
+ n
> CCALL_MAXSTACK
) { /* Too many arguments. */
769 lj_err_caller(L
, LJ_ERR_FFI_NYICALL
);
771 dp
= &cc
->stack
[nsp
];
776 if (rp
) { /* Pass by reference. */
781 lj_cconv_ct_tv(cts
, d
, (uint8_t *)dp
, o
, CCF_ARG(narg
));
782 /* Extend passed integers to 32 bits at least. */
783 if (ctype_isinteger_or_bool(d
->info
) && d
->size
< 4) {
784 if (d
->info
& CTF_UNSIGNED
)
785 *(uint32_t *)dp
= d
->size
== 1 ? (uint32_t)*(uint8_t *)dp
:
786 (uint32_t)*(uint16_t *)dp
;
788 *(int32_t *)dp
= d
->size
== 1 ? (int32_t)*(int8_t *)dp
:
789 (int32_t)*(int16_t *)dp
;
791 #if LJ_TARGET_X64 && LJ_ABI_WIN
792 if (isva
) { /* Windows/x64 mirrors varargs in both register sets. */
794 cc
->gpr
[ngpr
-1] = cc
->fpr
[ngpr
-1].l
[0];
796 cc
->fpr
[ngpr
-1].l
[0] = cc
->gpr
[ngpr
-1];
801 #if LJ_TARGET_X64 && !LJ_ABI_WIN
802 if (isfp
== 2 && n
== 2 && (uint8_t *)dp
== (uint8_t *)&cc
->fpr
[nfpr
-2]) {
803 cc
->fpr
[nfpr
-1].d
[0] = cc
->fpr
[nfpr
-2].d
[1]; /* Split complex double. */
804 cc
->fpr
[nfpr
-2].d
[1] = 0;
810 if (fid
) lj_err_caller(L
, LJ_ERR_FFI_NUMARG
); /* Too few arguments. */
812 #if LJ_TARGET_X64 || LJ_TARGET_PPC
813 cc
->nfpr
= nfpr
; /* Required for vararg functions. */
816 cc
->spadj
= (CCALL_SPS_FREE
+ CCALL_SPS_EXTRA
)*CTSIZE_PTR
;
817 if (nsp
> CCALL_SPS_FREE
)
818 cc
->spadj
+= (((nsp
-CCALL_SPS_FREE
)*CTSIZE_PTR
+ 15u) & ~15u);
822 /* Get results from C call. */
823 static int ccall_get_results(lua_State
*L
, CTState
*cts
, CType
*ct
,
824 CCallState
*cc
, int *ret
)
826 CType
*ctr
= ctype_rawchild(cts
, ct
);
827 uint8_t *sp
= (uint8_t *)&cc
->gpr
[0];
828 if (ctype_isvoid(ctr
->info
)) {
829 *ret
= 0; /* Zero results. */
830 return 0; /* No additional GC step. */
832 *ret
= 1; /* One result. */
833 if (ctype_isstruct(ctr
->info
)) {
834 /* Return cdata object which is already on top of stack. */
836 void *dp
= cdataptr(cdataV(L
->top
-1)); /* Use preallocated object. */
837 CCALL_HANDLE_STRUCTRET2
839 return 1; /* One GC step. */
841 if (ctype_iscomplex(ctr
->info
)) {
842 /* Return cdata object which is already on top of stack. */
843 void *dp
= cdataptr(cdataV(L
->top
-1)); /* Use preallocated object. */
844 CCALL_HANDLE_COMPLEXRET2
845 return 1; /* One GC step. */
847 if (LJ_BE
&& ctype_isinteger_or_bool(ctr
->info
) && ctr
->size
< CTSIZE_PTR
)
848 sp
+= (CTSIZE_PTR
- ctr
->size
);
850 if (ctype_isfp(ctr
->info
) || ctype_isvector(ctr
->info
))
851 sp
= (uint8_t *)&cc
->fpr
[0];
853 #ifdef CCALL_HANDLE_RET
856 /* No reference types end up here, so there's no need for the CTypeID. */
857 lua_assert(!(ctype_isrefarray(ctr
->info
) || ctype_isstruct(ctr
->info
)));
858 return lj_cconv_tv_ct(cts
, ctr
, 0, L
->top
-1, sp
);
861 /* Call C function. */
862 int lj_ccall_func(lua_State
*L
, GCcdata
*cd
)
864 CTState
*cts
= ctype_cts(L
);
865 CType
*ct
= ctype_raw(cts
, cd
->ctypeid
);
866 CTSize sz
= CTSIZE_PTR
;
867 if (ctype_isptr(ct
->info
)) {
869 ct
= ctype_rawchild(cts
, ct
);
871 if (ctype_isfunc(ct
->info
)) {
874 cc
.func
= (void (*)(void))cdata_getptr(cdataptr(cd
), sz
);
875 gcsteps
= ccall_set_args(L
, cts
, ct
, &cc
);
876 ct
= (CType
*)((intptr_t)ct
-(intptr_t)cts
->tab
);
879 if (cts
->cb
.slot
!= ~0u) { /* Blacklist function that called a callback. */
881 setlightudV(&tv
, (void *)cc
.func
);
882 setboolV(lj_tab_set(L
, cts
->miscmap
, &tv
), 1);
884 ct
= (CType
*)((intptr_t)ct
+(intptr_t)cts
->tab
); /* May be reallocated. */
885 gcsteps
+= ccall_get_results(L
, cts
, ct
, &cc
, &ret
);
886 #if LJ_TARGET_X86 && LJ_ABI_WIN
887 /* Automatically detect __stdcall and fix up C function declaration. */
888 if (cc
.spadj
&& ctype_cconv(ct
->info
) == CTCC_CDECL
) {
889 CTF_INSERT(ct
->info
, CCONV
, CTCC_STDCALL
);
890 lj_trace_abort(G(L
));
893 while (gcsteps
-- > 0)
897 return -1; /* Not a function. */