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Diffstat (limited to 'libs/luajit-cmake/luajit/src/lj_ccallback.c')
-rw-r--r--libs/luajit-cmake/luajit/src/lj_ccallback.c796
1 files changed, 796 insertions, 0 deletions
diff --git a/libs/luajit-cmake/luajit/src/lj_ccallback.c b/libs/luajit-cmake/luajit/src/lj_ccallback.c
new file mode 100644
index 0000000..43e4430
--- /dev/null
+++ b/libs/luajit-cmake/luajit/src/lj_ccallback.c
@@ -0,0 +1,796 @@
+/*
+** FFI C callback handling.
+** Copyright (C) 2005-2022 Mike Pall. See Copyright Notice in luajit.h
+*/
+
+#include "lj_obj.h"
+
+#if LJ_HASFFI
+
+#include "lj_gc.h"
+#include "lj_err.h"
+#include "lj_tab.h"
+#include "lj_state.h"
+#include "lj_frame.h"
+#include "lj_ctype.h"
+#include "lj_cconv.h"
+#include "lj_ccall.h"
+#include "lj_ccallback.h"
+#include "lj_target.h"
+#include "lj_mcode.h"
+#include "lj_trace.h"
+#include "lj_vm.h"
+
+/* -- Target-specific handling of callback slots -------------------------- */
+
+#define CALLBACK_MCODE_SIZE (LJ_PAGESIZE * LJ_NUM_CBPAGE)
+
+#if LJ_OS_NOJIT
+
+/* Callbacks disabled. */
+#define CALLBACK_SLOT2OFS(slot) (0*(slot))
+#define CALLBACK_OFS2SLOT(ofs) (0*(ofs))
+#define CALLBACK_MAX_SLOT 0
+
+#elif LJ_TARGET_X86ORX64
+
+#define CALLBACK_MCODE_HEAD (LJ_64 ? 8 : 0)
+#define CALLBACK_MCODE_GROUP (-2+1+2+(LJ_GC64 ? 10 : 5)+(LJ_64 ? 6 : 5))
+
+#define CALLBACK_SLOT2OFS(slot) \
+ (CALLBACK_MCODE_HEAD + CALLBACK_MCODE_GROUP*((slot)/32) + 4*(slot))
+
+static MSize CALLBACK_OFS2SLOT(MSize ofs)
+{
+ MSize group;
+ ofs -= CALLBACK_MCODE_HEAD;
+ group = ofs / (32*4 + CALLBACK_MCODE_GROUP);
+ return (ofs % (32*4 + CALLBACK_MCODE_GROUP))/4 + group*32;
+}
+
+#define CALLBACK_MAX_SLOT \
+ (((CALLBACK_MCODE_SIZE-CALLBACK_MCODE_HEAD)/(CALLBACK_MCODE_GROUP+4*32))*32)
+
+#elif LJ_TARGET_ARM
+
+#define CALLBACK_MCODE_HEAD 32
+
+#elif LJ_TARGET_ARM64
+
+#define CALLBACK_MCODE_HEAD 32
+
+#elif LJ_TARGET_PPC
+
+#define CALLBACK_MCODE_HEAD 24
+
+#elif LJ_TARGET_MIPS32
+
+#define CALLBACK_MCODE_HEAD 20
+
+#elif LJ_TARGET_MIPS64
+
+#define CALLBACK_MCODE_HEAD 52
+
+#else
+
+/* Missing support for this architecture. */
+#define CALLBACK_SLOT2OFS(slot) (0*(slot))
+#define CALLBACK_OFS2SLOT(ofs) (0*(ofs))
+#define CALLBACK_MAX_SLOT 0
+
+#endif
+
+#ifndef CALLBACK_SLOT2OFS
+#define CALLBACK_SLOT2OFS(slot) (CALLBACK_MCODE_HEAD + 8*(slot))
+#define CALLBACK_OFS2SLOT(ofs) (((ofs)-CALLBACK_MCODE_HEAD)/8)
+#define CALLBACK_MAX_SLOT (CALLBACK_OFS2SLOT(CALLBACK_MCODE_SIZE))
+#endif
+
+/* Convert callback slot number to callback function pointer. */
+static void *callback_slot2ptr(CTState *cts, MSize slot)
+{
+ return (uint8_t *)cts->cb.mcode + CALLBACK_SLOT2OFS(slot);
+}
+
+/* Convert callback function pointer to slot number. */
+MSize lj_ccallback_ptr2slot(CTState *cts, void *p)
+{
+ uintptr_t ofs = (uintptr_t)((uint8_t *)p -(uint8_t *)cts->cb.mcode);
+ if (ofs < CALLBACK_MCODE_SIZE) {
+ MSize slot = CALLBACK_OFS2SLOT((MSize)ofs);
+ if (CALLBACK_SLOT2OFS(slot) == (MSize)ofs)
+ return slot;
+ }
+ return ~0u; /* Not a known callback function pointer. */
+}
+
+/* Initialize machine code for callback function pointers. */
+#if LJ_OS_NOJIT
+/* Disabled callback support. */
+#define callback_mcode_init(g, p) (p)
+#elif LJ_TARGET_X86ORX64
+static void *callback_mcode_init(global_State *g, uint8_t *page)
+{
+ uint8_t *p = page;
+ uint8_t *target = (uint8_t *)(void *)lj_vm_ffi_callback;
+ MSize slot;
+#if LJ_64
+ *(void **)p = target; p += 8;
+#endif
+ for (slot = 0; slot < CALLBACK_MAX_SLOT; slot++) {
+ /* mov al, slot; jmp group */
+ *p++ = XI_MOVrib | RID_EAX; *p++ = (uint8_t)slot;
+ if ((slot & 31) == 31 || slot == CALLBACK_MAX_SLOT-1) {
+ /* push ebp/rbp; mov ah, slot>>8; mov ebp, &g. */
+ *p++ = XI_PUSH + RID_EBP;
+ *p++ = XI_MOVrib | (RID_EAX+4); *p++ = (uint8_t)(slot >> 8);
+#if LJ_GC64
+ *p++ = 0x48; *p++ = XI_MOVri | RID_EBP;
+ *(uint64_t *)p = (uint64_t)(g); p += 8;
+#else
+ *p++ = XI_MOVri | RID_EBP;
+ *(int32_t *)p = i32ptr(g); p += 4;
+#endif
+#if LJ_64
+ /* jmp [rip-pageofs] where lj_vm_ffi_callback is stored. */
+ *p++ = XI_GROUP5; *p++ = XM_OFS0 + (XOg_JMP<<3) + RID_EBP;
+ *(int32_t *)p = (int32_t)(page-(p+4)); p += 4;
+#else
+ /* jmp lj_vm_ffi_callback. */
+ *p++ = XI_JMP; *(int32_t *)p = target-(p+4); p += 4;
+#endif
+ } else {
+ *p++ = XI_JMPs; *p++ = (uint8_t)((2+2)*(31-(slot&31)) - 2);
+ }
+ }
+ return p;
+}
+#elif LJ_TARGET_ARM
+static void *callback_mcode_init(global_State *g, uint32_t *page)
+{
+ uint32_t *p = page;
+ void *target = (void *)lj_vm_ffi_callback;
+ MSize slot;
+ /* This must match with the saveregs macro in buildvm_arm.dasc. */
+ *p++ = ARMI_SUB|ARMF_D(RID_R12)|ARMF_N(RID_R12)|ARMF_M(RID_PC);
+ *p++ = ARMI_PUSH|ARMF_N(RID_SP)|RSET_RANGE(RID_R4,RID_R11+1)|RID2RSET(RID_LR);
+ *p++ = ARMI_SUB|ARMI_K12|ARMF_D(RID_R12)|ARMF_N(RID_R12)|CALLBACK_MCODE_HEAD;
+ *p++ = ARMI_STR|ARMI_LS_P|ARMI_LS_W|ARMF_D(RID_R12)|ARMF_N(RID_SP)|(CFRAME_SIZE-4*9);
+ *p++ = ARMI_LDR|ARMI_LS_P|ARMI_LS_U|ARMF_D(RID_R12)|ARMF_N(RID_PC);
+ *p++ = ARMI_LDR|ARMI_LS_P|ARMI_LS_U|ARMF_D(RID_PC)|ARMF_N(RID_PC);
+ *p++ = u32ptr(g);
+ *p++ = u32ptr(target);
+ for (slot = 0; slot < CALLBACK_MAX_SLOT; slot++) {
+ *p++ = ARMI_MOV|ARMF_D(RID_R12)|ARMF_M(RID_PC);
+ *p = ARMI_B | ((page-p-2) & 0x00ffffffu);
+ p++;
+ }
+ return p;
+}
+#elif LJ_TARGET_ARM64
+static void *callback_mcode_init(global_State *g, uint32_t *page)
+{
+ uint32_t *p = page;
+ void *target = (void *)lj_vm_ffi_callback;
+ MSize slot;
+ *p++ = A64I_LE(A64I_LDRLx | A64F_D(RID_X11) | A64F_S19(4));
+ *p++ = A64I_LE(A64I_LDRLx | A64F_D(RID_X10) | A64F_S19(5));
+ *p++ = A64I_LE(A64I_BR | A64F_N(RID_X11));
+ *p++ = A64I_LE(A64I_NOP);
+ ((void **)p)[0] = target;
+ ((void **)p)[1] = g;
+ p += 4;
+ for (slot = 0; slot < CALLBACK_MAX_SLOT; slot++) {
+ *p++ = A64I_LE(A64I_MOVZw | A64F_D(RID_X9) | A64F_U16(slot));
+ *p = A64I_LE(A64I_B | A64F_S26((page-p) & 0x03ffffffu));
+ p++;
+ }
+ return p;
+}
+#elif LJ_TARGET_PPC
+static void *callback_mcode_init(global_State *g, uint32_t *page)
+{
+ uint32_t *p = page;
+ void *target = (void *)lj_vm_ffi_callback;
+ MSize slot;
+ *p++ = PPCI_LIS | PPCF_T(RID_TMP) | (u32ptr(target) >> 16);
+ *p++ = PPCI_LIS | PPCF_T(RID_R12) | (u32ptr(g) >> 16);
+ *p++ = PPCI_ORI | PPCF_A(RID_TMP)|PPCF_T(RID_TMP) | (u32ptr(target) & 0xffff);
+ *p++ = PPCI_ORI | PPCF_A(RID_R12)|PPCF_T(RID_R12) | (u32ptr(g) & 0xffff);
+ *p++ = PPCI_MTCTR | PPCF_T(RID_TMP);
+ *p++ = PPCI_BCTR;
+ for (slot = 0; slot < CALLBACK_MAX_SLOT; slot++) {
+ *p++ = PPCI_LI | PPCF_T(RID_R11) | slot;
+ *p = PPCI_B | (((page-p) & 0x00ffffffu) << 2);
+ p++;
+ }
+ return p;
+}
+#elif LJ_TARGET_MIPS
+static void *callback_mcode_init(global_State *g, uint32_t *page)
+{
+ uint32_t *p = page;
+ uintptr_t target = (uintptr_t)(void *)lj_vm_ffi_callback;
+ uintptr_t ug = (uintptr_t)(void *)g;
+ MSize slot;
+#if LJ_TARGET_MIPS32
+ *p++ = MIPSI_LUI | MIPSF_T(RID_R3) | (target >> 16);
+ *p++ = MIPSI_LUI | MIPSF_T(RID_R2) | (ug >> 16);
+#else
+ *p++ = MIPSI_LUI | MIPSF_T(RID_R3) | (target >> 48);
+ *p++ = MIPSI_LUI | MIPSF_T(RID_R2) | (ug >> 48);
+ *p++ = MIPSI_ORI | MIPSF_T(RID_R3)|MIPSF_S(RID_R3) | ((target >> 32) & 0xffff);
+ *p++ = MIPSI_ORI | MIPSF_T(RID_R2)|MIPSF_S(RID_R2) | ((ug >> 32) & 0xffff);
+ *p++ = MIPSI_DSLL | MIPSF_D(RID_R3)|MIPSF_T(RID_R3) | MIPSF_A(16);
+ *p++ = MIPSI_DSLL | MIPSF_D(RID_R2)|MIPSF_T(RID_R2) | MIPSF_A(16);
+ *p++ = MIPSI_ORI | MIPSF_T(RID_R3)|MIPSF_S(RID_R3) | ((target >> 16) & 0xffff);
+ *p++ = MIPSI_ORI | MIPSF_T(RID_R2)|MIPSF_S(RID_R2) | ((ug >> 16) & 0xffff);
+ *p++ = MIPSI_DSLL | MIPSF_D(RID_R3)|MIPSF_T(RID_R3) | MIPSF_A(16);
+ *p++ = MIPSI_DSLL | MIPSF_D(RID_R2)|MIPSF_T(RID_R2) | MIPSF_A(16);
+#endif
+ *p++ = MIPSI_ORI | MIPSF_T(RID_R3)|MIPSF_S(RID_R3) | (target & 0xffff);
+ *p++ = MIPSI_JR | MIPSF_S(RID_R3);
+ *p++ = MIPSI_ORI | MIPSF_T(RID_R2)|MIPSF_S(RID_R2) | (ug & 0xffff);
+ for (slot = 0; slot < CALLBACK_MAX_SLOT; slot++) {
+ *p = MIPSI_B | ((page-p-1) & 0x0000ffffu);
+ p++;
+ *p++ = MIPSI_LI | MIPSF_T(RID_R1) | slot;
+ }
+ return p;
+}
+#else
+/* Missing support for this architecture. */
+#define callback_mcode_init(g, p) (p)
+#endif
+
+/* -- Machine code management --------------------------------------------- */
+
+#if LJ_TARGET_WINDOWS
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+#elif LJ_TARGET_POSIX
+
+#include <sys/mman.h>
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+#ifdef PROT_MPROTECT
+#define CCPROT_CREATE (PROT_MPROTECT(PROT_EXEC))
+#else
+#define CCPROT_CREATE 0
+#endif
+
+#endif
+
+/* Allocate and initialize area for callback function pointers. */
+static void callback_mcode_new(CTState *cts)
+{
+ size_t sz = (size_t)CALLBACK_MCODE_SIZE;
+ void *p, *pe;
+ if (CALLBACK_MAX_SLOT == 0)
+ lj_err_caller(cts->L, LJ_ERR_FFI_CBACKOV);
+#if LJ_TARGET_WINDOWS
+ p = LJ_WIN_VALLOC(NULL, sz, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
+ if (!p)
+ lj_err_caller(cts->L, LJ_ERR_FFI_CBACKOV);
+#elif LJ_TARGET_POSIX
+ p = mmap(NULL, sz, (PROT_READ|PROT_WRITE|CCPROT_CREATE), MAP_PRIVATE|MAP_ANONYMOUS,
+ -1, 0);
+ if (p == MAP_FAILED)
+ lj_err_caller(cts->L, LJ_ERR_FFI_CBACKOV);
+#else
+ /* Fallback allocator. Fails if memory is not executable by default. */
+ p = lj_mem_new(cts->L, sz);
+#endif
+ cts->cb.mcode = p;
+ pe = callback_mcode_init(cts->g, p);
+ UNUSED(pe);
+ lj_assertCTS((size_t)((char *)pe - (char *)p) <= sz,
+ "miscalculated CALLBACK_MAX_SLOT");
+ lj_mcode_sync(p, (char *)p + sz);
+#if LJ_TARGET_WINDOWS
+ {
+ DWORD oprot;
+ LJ_WIN_VPROTECT(p, sz, PAGE_EXECUTE_READ, &oprot);
+ }
+#elif LJ_TARGET_POSIX
+ mprotect(p, sz, (PROT_READ|PROT_EXEC));
+#endif
+}
+
+/* Free area for callback function pointers. */
+void lj_ccallback_mcode_free(CTState *cts)
+{
+ size_t sz = (size_t)CALLBACK_MCODE_SIZE;
+ void *p = cts->cb.mcode;
+ if (p == NULL) return;
+#if LJ_TARGET_WINDOWS
+ VirtualFree(p, 0, MEM_RELEASE);
+ UNUSED(sz);
+#elif LJ_TARGET_POSIX
+ munmap(p, sz);
+#else
+ lj_mem_free(cts->g, p, sz);
+#endif
+}
+
+/* -- C callback entry ---------------------------------------------------- */
+
+/* Target-specific handling of register arguments. Similar to lj_ccall.c. */
+#if LJ_TARGET_X86
+
+#define CALLBACK_HANDLE_REGARG \
+ if (!isfp) { /* Only non-FP values may be passed in registers. */ \
+ if (n > 1) { /* Anything > 32 bit is passed on the stack. */ \
+ if (!LJ_ABI_WIN) ngpr = maxgpr; /* Prevent reordering. */ \
+ } else if (ngpr + 1 <= maxgpr) { \
+ sp = &cts->cb.gpr[ngpr]; \
+ ngpr += n; \
+ goto done; \
+ } \
+ }
+
+#elif LJ_TARGET_X64 && LJ_ABI_WIN
+
+/* Windows/x64 argument registers are strictly positional (use ngpr). */
+#define CALLBACK_HANDLE_REGARG \
+ if (isfp) { \
+ if (ngpr < maxgpr) { sp = &cts->cb.fpr[ngpr++]; UNUSED(nfpr); goto done; } \
+ } else { \
+ if (ngpr < maxgpr) { sp = &cts->cb.gpr[ngpr++]; goto done; } \
+ }
+
+#elif LJ_TARGET_X64
+
+#define CALLBACK_HANDLE_REGARG \
+ if (isfp) { \
+ if (nfpr + n <= CCALL_NARG_FPR) { \
+ sp = &cts->cb.fpr[nfpr]; \
+ nfpr += n; \
+ goto done; \
+ } \
+ } else { \
+ if (ngpr + n <= maxgpr) { \
+ sp = &cts->cb.gpr[ngpr]; \
+ ngpr += n; \
+ goto done; \
+ } \
+ }
+
+#elif LJ_TARGET_ARM
+
+#if LJ_ABI_SOFTFP
+
+#define CALLBACK_HANDLE_REGARG_FP1 UNUSED(isfp);
+#define CALLBACK_HANDLE_REGARG_FP2
+
+#else
+
+#define CALLBACK_HANDLE_REGARG_FP1 \
+ if (isfp) { \
+ if (n == 1) { \
+ if (fprodd) { \
+ sp = &cts->cb.fpr[fprodd-1]; \
+ fprodd = 0; \
+ goto done; \
+ } else if (nfpr + 1 <= CCALL_NARG_FPR) { \
+ sp = &cts->cb.fpr[nfpr++]; \
+ fprodd = nfpr; \
+ goto done; \
+ } \
+ } else { \
+ if (nfpr + 1 <= CCALL_NARG_FPR) { \
+ sp = &cts->cb.fpr[nfpr++]; \
+ goto done; \
+ } \
+ } \
+ fprodd = 0; /* No reordering after the first FP value is on stack. */ \
+ } else {
+
+#define CALLBACK_HANDLE_REGARG_FP2 }
+
+#endif
+
+#define CALLBACK_HANDLE_REGARG \
+ CALLBACK_HANDLE_REGARG_FP1 \
+ if (n > 1) ngpr = (ngpr + 1u) & ~1u; /* Align to regpair. */ \
+ if (ngpr + n <= maxgpr) { \
+ sp = &cts->cb.gpr[ngpr]; \
+ ngpr += n; \
+ goto done; \
+ } CALLBACK_HANDLE_REGARG_FP2
+
+#elif LJ_TARGET_ARM64
+
+#define CALLBACK_HANDLE_REGARG \
+ if (isfp) { \
+ if (nfpr + n <= CCALL_NARG_FPR) { \
+ sp = &cts->cb.fpr[nfpr]; \
+ nfpr += n; \
+ goto done; \
+ } else { \
+ nfpr = CCALL_NARG_FPR; /* Prevent reordering. */ \
+ } \
+ } else { \
+ if (!LJ_TARGET_OSX && n > 1) \
+ ngpr = (ngpr + 1u) & ~1u; /* Align to regpair. */ \
+ if (ngpr + n <= maxgpr) { \
+ sp = &cts->cb.gpr[ngpr]; \
+ ngpr += n; \
+ goto done; \
+ } else { \
+ ngpr = CCALL_NARG_GPR; /* Prevent reordering. */ \
+ } \
+ }
+
+#elif LJ_TARGET_PPC
+
+#define CALLBACK_HANDLE_GPR \
+ if (n > 1) { \
+ lj_assertCTS(((LJ_ABI_SOFTFP && ctype_isnum(cta->info)) || /* double. */ \
+ ctype_isinteger(cta->info)) && n == 2, /* int64_t. */ \
+ "bad GPR type"); \
+ ngpr = (ngpr + 1u) & ~1u; /* Align int64_t to regpair. */ \
+ } \
+ if (ngpr + n <= maxgpr) { \
+ sp = &cts->cb.gpr[ngpr]; \
+ ngpr += n; \
+ goto done; \
+ }
+
+#if LJ_ABI_SOFTFP
+#define CALLBACK_HANDLE_REGARG \
+ CALLBACK_HANDLE_GPR \
+ UNUSED(isfp);
+#else
+#define CALLBACK_HANDLE_REGARG \
+ if (isfp) { \
+ if (nfpr + 1 <= CCALL_NARG_FPR) { \
+ sp = &cts->cb.fpr[nfpr++]; \
+ cta = ctype_get(cts, CTID_DOUBLE); /* FPRs always hold doubles. */ \
+ goto done; \
+ } \
+ } else { /* Try to pass argument in GPRs. */ \
+ CALLBACK_HANDLE_GPR \
+ }
+#endif
+
+#if !LJ_ABI_SOFTFP
+#define CALLBACK_HANDLE_RET \
+ if (ctype_isfp(ctr->info) && ctr->size == sizeof(float)) \
+ *(double *)dp = *(float *)dp; /* FPRs always hold doubles. */
+#endif
+
+#elif LJ_TARGET_MIPS32
+
+#define CALLBACK_HANDLE_GPR \
+ if (n > 1) ngpr = (ngpr + 1u) & ~1u; /* Align to regpair. */ \
+ if (ngpr + n <= maxgpr) { \
+ sp = &cts->cb.gpr[ngpr]; \
+ ngpr += n; \
+ goto done; \
+ }
+
+#if !LJ_ABI_SOFTFP /* MIPS32 hard-float */
+#define CALLBACK_HANDLE_REGARG \
+ if (isfp && nfpr < CCALL_NARG_FPR) { /* Try to pass argument in FPRs. */ \
+ sp = (void *)((uint8_t *)&cts->cb.fpr[nfpr] + ((LJ_BE && n==1) ? 4 : 0)); \
+ nfpr++; ngpr += n; \
+ goto done; \
+ } else { /* Try to pass argument in GPRs. */ \
+ nfpr = CCALL_NARG_FPR; \
+ CALLBACK_HANDLE_GPR \
+ }
+#else /* MIPS32 soft-float */
+#define CALLBACK_HANDLE_REGARG \
+ CALLBACK_HANDLE_GPR \
+ UNUSED(isfp);
+#endif
+
+#define CALLBACK_HANDLE_RET \
+ if (ctype_isfp(ctr->info) && ctr->size == sizeof(float)) \
+ ((float *)dp)[1] = *(float *)dp;
+
+#elif LJ_TARGET_MIPS64
+
+#if !LJ_ABI_SOFTFP /* MIPS64 hard-float */
+#define CALLBACK_HANDLE_REGARG \
+ if (ngpr + n <= maxgpr) { \
+ sp = isfp ? (void*) &cts->cb.fpr[ngpr] : (void*) &cts->cb.gpr[ngpr]; \
+ ngpr += n; \
+ goto done; \
+ }
+#else /* MIPS64 soft-float */
+#define CALLBACK_HANDLE_REGARG \
+ if (ngpr + n <= maxgpr) { \
+ UNUSED(isfp); \
+ sp = (void*) &cts->cb.gpr[ngpr]; \
+ ngpr += n; \
+ goto done; \
+ }
+#endif
+
+#define CALLBACK_HANDLE_RET \
+ if (ctype_isfp(ctr->info) && ctr->size == sizeof(float)) \
+ ((float *)dp)[1] = *(float *)dp;
+
+#else
+#error "Missing calling convention definitions for this architecture"
+#endif
+
+/* Convert and push callback arguments to Lua stack. */
+static void callback_conv_args(CTState *cts, lua_State *L)
+{
+ TValue *o = L->top;
+ intptr_t *stack = cts->cb.stack;
+ MSize slot = cts->cb.slot;
+ CTypeID id = 0, rid, fid;
+ int gcsteps = 0;
+ CType *ct;
+ GCfunc *fn;
+ int fntp;
+ MSize ngpr = 0, nsp = 0, maxgpr = CCALL_NARG_GPR;
+#if CCALL_NARG_FPR
+ MSize nfpr = 0;
+#if LJ_TARGET_ARM
+ MSize fprodd = 0;
+#endif
+#endif
+
+ if (slot < cts->cb.sizeid && (id = cts->cb.cbid[slot]) != 0) {
+ ct = ctype_get(cts, id);
+ rid = ctype_cid(ct->info); /* Return type. x86: +(spadj<<16). */
+ fn = funcV(lj_tab_getint(cts->miscmap, (int32_t)slot));
+ fntp = LJ_TFUNC;
+ } else { /* Must set up frame first, before throwing the error. */
+ ct = NULL;
+ rid = 0;
+ fn = (GCfunc *)L;
+ fntp = LJ_TTHREAD;
+ }
+ /* Continuation returns from callback. */
+ if (LJ_FR2) {
+ (o++)->u64 = LJ_CONT_FFI_CALLBACK;
+ (o++)->u64 = rid;
+ } else {
+ o->u32.lo = LJ_CONT_FFI_CALLBACK;
+ o->u32.hi = rid;
+ o++;
+ }
+ setframe_gc(o, obj2gco(fn), fntp);
+ if (LJ_FR2) o++;
+ setframe_ftsz(o, ((char *)(o+1) - (char *)L->base) + FRAME_CONT);
+ L->top = L->base = ++o;
+ if (!ct)
+ lj_err_caller(cts->L, LJ_ERR_FFI_BADCBACK);
+ if (isluafunc(fn))
+ setcframe_pc(L->cframe, proto_bc(funcproto(fn))+1);
+ lj_state_checkstack(L, LUA_MINSTACK); /* May throw. */
+ o = L->base; /* Might have been reallocated. */
+
+#if LJ_TARGET_X86
+ /* x86 has several different calling conventions. */
+ switch (ctype_cconv(ct->info)) {
+ case CTCC_FASTCALL: maxgpr = 2; break;
+ case CTCC_THISCALL: maxgpr = 1; break;
+ default: maxgpr = 0; break;
+ }
+#endif
+
+ fid = ct->sib;
+ while (fid) {
+ CType *ctf = ctype_get(cts, fid);
+ if (!ctype_isattrib(ctf->info)) {
+ CType *cta;
+ void *sp;
+ CTSize sz;
+ int isfp;
+ MSize n;
+ lj_assertCTS(ctype_isfield(ctf->info), "field expected");
+ cta = ctype_rawchild(cts, ctf);
+ isfp = ctype_isfp(cta->info);
+ sz = (cta->size + CTSIZE_PTR-1) & ~(CTSIZE_PTR-1);
+ n = sz / CTSIZE_PTR; /* Number of GPRs or stack slots needed. */
+
+ CALLBACK_HANDLE_REGARG /* Handle register arguments. */
+
+ /* Otherwise pass argument on stack. */
+ if (CCALL_ALIGN_STACKARG && LJ_32 && sz == 8)
+ nsp = (nsp + 1) & ~1u; /* Align 64 bit argument on stack. */
+ sp = &stack[nsp];
+ nsp += n;
+
+ done:
+ if (LJ_BE && cta->size < CTSIZE_PTR
+#if LJ_TARGET_MIPS64
+ && !(isfp && nsp)
+#endif
+ )
+ sp = (void *)((uint8_t *)sp + CTSIZE_PTR-cta->size);
+ gcsteps += lj_cconv_tv_ct(cts, cta, 0, o++, sp);
+ }
+ fid = ctf->sib;
+ }
+ L->top = o;
+#if LJ_TARGET_X86
+ /* Store stack adjustment for returns from non-cdecl callbacks. */
+ if (ctype_cconv(ct->info) != CTCC_CDECL) {
+#if LJ_FR2
+ (L->base-3)->u64 |= (nsp << (16+2));
+#else
+ (L->base-2)->u32.hi |= (nsp << (16+2));
+#endif
+ }
+#endif
+ while (gcsteps-- > 0)
+ lj_gc_check(L);
+}
+
+/* Convert Lua object to callback result. */
+static void callback_conv_result(CTState *cts, lua_State *L, TValue *o)
+{
+#if LJ_FR2
+ CType *ctr = ctype_raw(cts, (uint16_t)(L->base-3)->u64);
+#else
+ CType *ctr = ctype_raw(cts, (uint16_t)(L->base-2)->u32.hi);
+#endif
+#if LJ_TARGET_X86
+ cts->cb.gpr[2] = 0;
+#endif
+ if (!ctype_isvoid(ctr->info)) {
+ uint8_t *dp = (uint8_t *)&cts->cb.gpr[0];
+#if CCALL_NUM_FPR
+ if (ctype_isfp(ctr->info))
+ dp = (uint8_t *)&cts->cb.fpr[0];
+#endif
+#if LJ_TARGET_ARM64 && LJ_BE
+ if (ctype_isfp(ctr->info) && ctr->size == sizeof(float))
+ dp = (uint8_t *)&cts->cb.fpr[0].f[1];
+#endif
+ lj_cconv_ct_tv(cts, ctr, dp, o, 0);
+#ifdef CALLBACK_HANDLE_RET
+ CALLBACK_HANDLE_RET
+#endif
+ /* Extend returned integers to (at least) 32 bits. */
+ if (ctype_isinteger_or_bool(ctr->info) && ctr->size < 4) {
+ if (ctr->info & CTF_UNSIGNED)
+ *(uint32_t *)dp = ctr->size == 1 ? (uint32_t)*(uint8_t *)dp :
+ (uint32_t)*(uint16_t *)dp;
+ else
+ *(int32_t *)dp = ctr->size == 1 ? (int32_t)*(int8_t *)dp :
+ (int32_t)*(int16_t *)dp;
+ }
+#if LJ_TARGET_MIPS64 || (LJ_TARGET_ARM64 && LJ_BE)
+ /* Always sign-extend results to 64 bits. Even a soft-fp 'float'. */
+ if (ctr->size <= 4 &&
+ (LJ_ABI_SOFTFP || ctype_isinteger_or_bool(ctr->info)))
+ *(int64_t *)dp = (int64_t)*(int32_t *)dp;
+#endif
+#if LJ_TARGET_X86
+ if (ctype_isfp(ctr->info))
+ cts->cb.gpr[2] = ctr->size == sizeof(float) ? 1 : 2;
+#endif
+ }
+}
+
+/* Enter callback. */
+lua_State * LJ_FASTCALL lj_ccallback_enter(CTState *cts, void *cf)
+{
+ lua_State *L = cts->L;
+ global_State *g = cts->g;
+ lj_assertG(L != NULL, "uninitialized cts->L in callback");
+ if (tvref(g->jit_base)) {
+ setstrV(L, L->top++, lj_err_str(L, LJ_ERR_FFI_BADCBACK));
+ if (g->panic) g->panic(L);
+ exit(EXIT_FAILURE);
+ }
+ lj_trace_abort(g); /* Never record across callback. */
+ /* Setup C frame. */
+ cframe_prev(cf) = L->cframe;
+ setcframe_L(cf, L);
+ cframe_errfunc(cf) = -1;
+ cframe_nres(cf) = 0;
+ L->cframe = cf;
+ callback_conv_args(cts, L);
+ return L; /* Now call the function on this stack. */
+}
+
+/* Leave callback. */
+void LJ_FASTCALL lj_ccallback_leave(CTState *cts, TValue *o)
+{
+ lua_State *L = cts->L;
+ GCfunc *fn;
+ TValue *obase = L->base;
+ L->base = L->top; /* Keep continuation frame for throwing errors. */
+ if (o >= L->base) {
+ /* PC of RET* is lost. Point to last line for result conv. errors. */
+ fn = curr_func(L);
+ if (isluafunc(fn)) {
+ GCproto *pt = funcproto(fn);
+ setcframe_pc(L->cframe, proto_bc(pt)+pt->sizebc+1);
+ }
+ }
+ callback_conv_result(cts, L, o);
+ /* Finally drop C frame and continuation frame. */
+ L->top -= 2+2*LJ_FR2;
+ L->base = obase;
+ L->cframe = cframe_prev(L->cframe);
+ cts->cb.slot = 0; /* Blacklist C function that called the callback. */
+}
+
+/* -- C callback management ----------------------------------------------- */
+
+/* Get an unused slot in the callback slot table. */
+static MSize callback_slot_new(CTState *cts, CType *ct)
+{
+ CTypeID id = ctype_typeid(cts, ct);
+ CTypeID1 *cbid = cts->cb.cbid;
+ MSize top;
+ for (top = cts->cb.topid; top < cts->cb.sizeid; top++)
+ if (LJ_LIKELY(cbid[top] == 0))
+ goto found;
+#if CALLBACK_MAX_SLOT
+ if (top >= CALLBACK_MAX_SLOT)
+#endif
+ lj_err_caller(cts->L, LJ_ERR_FFI_CBACKOV);
+ if (!cts->cb.mcode)
+ callback_mcode_new(cts);
+ lj_mem_growvec(cts->L, cbid, cts->cb.sizeid, CALLBACK_MAX_SLOT, CTypeID1);
+ cts->cb.cbid = cbid;
+ memset(cbid+top, 0, (cts->cb.sizeid-top)*sizeof(CTypeID1));
+found:
+ cbid[top] = id;
+ cts->cb.topid = top+1;
+ return top;
+}
+
+/* Check for function pointer and supported argument/result types. */
+static CType *callback_checkfunc(CTState *cts, CType *ct)
+{
+ int narg = 0;
+ if (!ctype_isptr(ct->info) || (LJ_64 && ct->size != CTSIZE_PTR))
+ return NULL;
+ ct = ctype_rawchild(cts, ct);
+ if (ctype_isfunc(ct->info)) {
+ CType *ctr = ctype_rawchild(cts, ct);
+ CTypeID fid = ct->sib;
+ if (!(ctype_isvoid(ctr->info) || ctype_isenum(ctr->info) ||
+ ctype_isptr(ctr->info) || (ctype_isnum(ctr->info) && ctr->size <= 8)))
+ return NULL;
+ if ((ct->info & CTF_VARARG))
+ return NULL;
+ while (fid) {
+ CType *ctf = ctype_get(cts, fid);
+ if (!ctype_isattrib(ctf->info)) {
+ CType *cta;
+ lj_assertCTS(ctype_isfield(ctf->info), "field expected");
+ cta = ctype_rawchild(cts, ctf);
+ if (!(ctype_isenum(cta->info) || ctype_isptr(cta->info) ||
+ (ctype_isnum(cta->info) && cta->size <= 8)) ||
+ ++narg >= LUA_MINSTACK-3)
+ return NULL;
+ }
+ fid = ctf->sib;
+ }
+ return ct;
+ }
+ return NULL;
+}
+
+/* Create a new callback and return the callback function pointer. */
+void *lj_ccallback_new(CTState *cts, CType *ct, GCfunc *fn)
+{
+ ct = callback_checkfunc(cts, ct);
+ if (ct) {
+ MSize slot = callback_slot_new(cts, ct);
+ GCtab *t = cts->miscmap;
+ setfuncV(cts->L, lj_tab_setint(cts->L, t, (int32_t)slot), fn);
+ lj_gc_anybarriert(cts->L, t);
+ return callback_slot2ptr(cts, slot);
+ }
+ return NULL; /* Bad conversion. */
+}
+
+#endif