Jo Shields fe777c5c82 Imported Upstream version 3.8.0
Former-commit-id: 6a76a29bd07d86e57c6c8da45c65ed5447d38a61
2014-09-04 09:07:35 +01:00

1170 lines
36 KiB
C

/*
* tramp-x86.c: JIT trampoline code for x86
*
* Authors:
* Dietmar Maurer (dietmar@ximian.com)
*
* (C) 2001 Ximian, Inc.
*/
#include <config.h>
#include <glib.h>
#include <mono/metadata/abi-details.h>
#include <mono/metadata/appdomain.h>
#include <mono/metadata/metadata-internals.h>
#include <mono/metadata/marshal.h>
#include <mono/metadata/tabledefs.h>
#include <mono/metadata/mono-debug.h>
#include <mono/metadata/mono-debug-debugger.h>
#include <mono/metadata/monitor.h>
#include <mono/metadata/gc-internal.h>
#include <mono/arch/x86/x86-codegen.h>
#include <mono/utils/memcheck.h>
#include "mini.h"
#include "mini-x86.h"
#define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
/*
* mono_arch_get_unbox_trampoline:
* @m: method pointer
* @addr: pointer to native code for @m
*
* when value type methods are called through the vtable we need to unbox the
* this argument. This method returns a pointer to a trampoline which does
* unboxing before calling the method
*/
gpointer
mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
{
guint8 *code, *start;
int this_pos = 4, size = NACL_SIZE(16, 32);
MonoDomain *domain = mono_domain_get ();
start = code = mono_domain_code_reserve (domain, size);
x86_alu_membase_imm (code, X86_ADD, X86_ESP, this_pos, sizeof (MonoObject));
x86_jump_code (code, addr);
g_assert ((code - start) < size);
nacl_domain_code_validate (domain, &start, size, &code);
return start;
}
gpointer
mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
{
guint8 *code, *start;
int buf_len;
MonoDomain *domain = mono_domain_get ();
buf_len = NACL_SIZE (10, 32);
start = code = mono_domain_code_reserve (domain, buf_len);
x86_mov_reg_imm (code, MONO_ARCH_RGCTX_REG, mrgctx);
x86_jump_code (code, addr);
g_assert ((code - start) <= buf_len);
nacl_domain_code_validate (domain, &start, buf_len, &code);
mono_arch_flush_icache (start, code - start);
return start;
}
gpointer
mono_arch_get_llvm_imt_trampoline (MonoDomain *domain, MonoMethod *m, int vt_offset)
{
guint8 *code, *start;
int buf_len;
int this_offset;
buf_len = 32;
start = code = mono_domain_code_reserve (domain, buf_len);
this_offset = mono_x86_get_this_arg_offset (NULL, mono_method_signature (m));
/* Set imt arg */
x86_mov_reg_imm (code, MONO_ARCH_IMT_REG, m);
/* Load this */
x86_mov_reg_membase (code, X86_EAX, X86_ESP, this_offset + 4, 4);
/* Load vtable address */
x86_mov_reg_membase (code, X86_EAX, X86_EAX, 0, 4);
x86_jump_membase (code, X86_EAX, vt_offset);
g_assert ((code - start) < buf_len);
nacl_domain_code_validate (domain, &start, buf_len, &code);
mono_arch_flush_icache (start, code - start);
return start;
}
void
mono_arch_patch_callsite (guint8 *method_start, guint8 *orig_code, guint8 *addr)
{
#if defined(__default_codegen__)
guint8 *code;
guint8 buf [8];
gboolean can_write = mono_breakpoint_clean_code (method_start, orig_code, 8, buf, sizeof (buf));
code = buf + 8;
/* go to the start of the call instruction
*
* address_byte = (m << 6) | (o << 3) | reg
* call opcode: 0xff address_byte displacement
* 0xff m=1,o=2 imm8
* 0xff m=2,o=2 imm32
*/
code -= 6;
orig_code -= 6;
if (code [1] == 0xe8) {
if (can_write) {
InterlockedExchange ((gint32*)(orig_code + 2), (guint)addr - ((guint)orig_code + 1) - 5);
/* Tell valgrind to recompile the patched code */
VALGRIND_DISCARD_TRANSLATIONS (orig_code + 2, 4);
}
} else if (code [1] == 0xe9) {
/* A PLT entry: jmp <DISP> */
if (can_write)
InterlockedExchange ((gint32*)(orig_code + 2), (guint)addr - ((guint)orig_code + 1) - 5);
} else {
printf ("Invalid trampoline sequence: %x %x %x %x %x %x %x\n", code [0], code [1], code [2], code [3],
code [4], code [5], code [6]);
g_assert_not_reached ();
}
#elif defined(__native_client__)
/* Target must be bundle-aligned */
g_assert (((guint32)addr & kNaClAlignmentMask) == 0);
/* 0xe8 = call <DISP>, 0xe9 = jump <DISP> */
if ((orig_code [-5] == 0xe8) || orig_code [-6] == 0xe9) {
int ret;
gint32 offset = (gint32)addr - (gint32)orig_code;
guint8 buf[sizeof(gint32)];
*((gint32*)(buf)) = offset;
ret = nacl_dyncode_modify (orig_code - sizeof(gint32), buf, sizeof(gint32));
g_assert (ret == 0);
} else {
printf ("Invalid trampoline sequence %p: %02x %02x %02x %02x %02x\n", orig_code, orig_code [-5], orig_code [-4], orig_code [-3], orig_code [-2], orig_code[-1]);
g_assert_not_reached ();
}
#endif
}
void
mono_arch_patch_plt_entry (guint8 *code, gpointer *got, mgreg_t *regs, guint8 *addr)
{
guint32 offset;
/* Patch the jump table entry used by the plt entry */
#if defined(__native_client_codegen__) || defined(__native_client__)
/* for both compiler and runtime */
/* A PLT entry: */
/* mov <DISP>(%ebx), %ecx */
/* and 0xffffffe0, %ecx */
/* jmp *%ecx */
g_assert (code [0] == 0x8b);
g_assert (code [1] == 0x8b);
offset = *(guint32*)(code + 2);
#elif defined(__default_codegen__)
/* A PLT entry: jmp *<DISP>(%ebx) */
g_assert (code [0] == 0xff);
g_assert (code [1] == 0xa3);
offset = *(guint32*)(code + 2);
#endif /* __native_client_codegen__ */
if (!got)
got = (gpointer*)(gsize) regs [MONO_ARCH_GOT_REG];
*(guint8**)((guint8*)got + offset) = addr;
}
static gpointer
get_vcall_slot (guint8 *code, mgreg_t *regs, int *displacement)
{
const int kBufSize = NACL_SIZE (8, 16);
guint8 buf [64];
guint8 reg = 0;
gint32 disp = 0;
mono_breakpoint_clean_code (NULL, code, kBufSize, buf, kBufSize);
code = buf + 8;
*displacement = 0;
if ((code [0] == 0xff) && ((code [1] & 0x18) == 0x10) && ((code [1] >> 6) == 2)) {
reg = code [1] & 0x07;
disp = *((gint32*)(code + 2));
#if defined(__native_client_codegen__) || defined(__native_client__)
} else if ((code[1] == 0x83) && (code[2] == 0xe1) && (code[4] == 0xff) &&
(code[5] == 0xd1) && (code[-5] == 0x8b)) {
disp = *((gint32*)(code - 3));
reg = code[-4] & 0x07;
} else if ((code[-2] == 0x8b) && (code[1] == 0x83) && (code[4] == 0xff)) {
reg = code[-1] & 0x07;
disp = (signed char)code[0];
#endif
} else {
g_assert_not_reached ();
return NULL;
}
*displacement = disp;
return (gpointer)regs [reg];
}
static gpointer*
get_vcall_slot_addr (guint8* code, mgreg_t *regs)
{
gpointer vt;
int displacement;
vt = get_vcall_slot (code, regs, &displacement);
if (!vt)
return NULL;
return (gpointer*)((char*)vt + displacement);
}
void
mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
{
guint8 buf [16];
gboolean can_write = mono_breakpoint_clean_code (NULL, code, 6, buf, sizeof (buf));
gpointer tramp = mini_get_nullified_class_init_trampoline ();
if (!can_write)
return;
code -= 5;
if (code [0] == 0xe8) {
#if defined(__default_codegen__)
if (!mono_running_on_valgrind ()) {
guint32 ops;
/*
* Thread safe code patching using the algorithm from the paper
* 'Practicing JUDO: Java Under Dynamic Optimizations'
*/
/*
* First atomically change the the first 2 bytes of the call to a
* spinning jump.
*/
ops = 0xfeeb;
InterlockedExchange ((gint32*)code, ops);
/* Then change the other bytes to a nop */
code [2] = 0x90;
code [3] = 0x90;
code [4] = 0x90;
/* Then atomically change the first 4 bytes to a nop as well */
ops = 0x90909090;
InterlockedExchange ((gint32*)code, ops);
/* FIXME: the calltree skin trips on the self modifying code above */
/* Tell valgrind to recompile the patched code */
//VALGRIND_DISCARD_TRANSLATIONS (code, 8);
}
#elif defined(__native_client_codegen__)
mono_arch_patch_callsite (code, code + 5, tramp);
#endif
} else if (code [0] == 0x90 || code [0] == 0xeb) {
/* Already changed by another thread */
;
} else if ((code [-1] == 0xff) && (x86_modrm_reg (code [0]) == 0x2)) {
/* call *<OFFSET>(<REG>) -> Call made from AOT code */
gpointer *vtable_slot;
vtable_slot = get_vcall_slot_addr (code + 5, regs);
g_assert (vtable_slot);
*vtable_slot = tramp;
} else {
printf ("Invalid trampoline sequence: %x %x %x %x %x %x %x\n", code [0], code [1], code [2], code [3],
code [4], code [5], code [6]);
g_assert_not_reached ();
}
}
guchar*
mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
{
char *tramp_name;
guint8 *buf, *code, *tramp;
GSList *unwind_ops = NULL;
MonoJumpInfo *ji = NULL;
int i, offset, frame_size, regarray_offset, lmf_offset, caller_ip_offset, arg_offset;
unwind_ops = mono_arch_get_cie_program ();
code = buf = mono_global_codeman_reserve (256);
/* Note that there is a single argument to the trampoline
* and it is stored at: esp + pushed_args * sizeof (gpointer)
* the ret address is at: esp + (pushed_args + 1) * sizeof (gpointer)
*/
// FIXME: Unwind info
/* Compute frame offsets relative to the frame pointer %ebp */
arg_offset = sizeof (mgreg_t);
caller_ip_offset = 2 * sizeof (mgreg_t);
offset = 0;
offset += sizeof (MonoLMF);
lmf_offset = -offset;
offset += X86_NREG * sizeof (mgreg_t);
regarray_offset = -offset;
/* Argument area */
offset += 4 * sizeof (mgreg_t);
frame_size = ALIGN_TO (offset, MONO_ARCH_FRAME_ALIGNMENT);
/* Allocate frame */
x86_push_reg (code, X86_EBP);
x86_mov_reg_reg (code, X86_EBP, X86_ESP, sizeof (mgreg_t));
/* There are three words on the stack, adding + 4 aligns the stack to 16, which is needed on osx */
x86_alu_reg_imm (code, X86_SUB, X86_ESP, frame_size + sizeof (mgreg_t));
/* Save all registers */
for (i = X86_EAX; i <= X86_EDI; ++i) {
int reg = i;
if (i == X86_EBP) {
/* Save original ebp */
/* EAX is already saved */
x86_mov_reg_membase (code, X86_EAX, X86_EBP, 0, sizeof (mgreg_t));
reg = X86_EAX;
} else if (i == X86_ESP) {
/* Save original esp */
/* EAX is already saved */
x86_mov_reg_reg (code, X86_EAX, X86_EBP, sizeof (mgreg_t));
/* Saved ebp + trampoline arg + return addr */
x86_alu_reg_imm (code, X86_ADD, X86_EAX, 3 * sizeof (mgreg_t));
reg = X86_EAX;
}
x86_mov_membase_reg (code, X86_EBP, regarray_offset + (i * sizeof (mgreg_t)), reg, sizeof (mgreg_t));
}
/* Setup LMF */
/* eip */
if (tramp_type == MONO_TRAMPOLINE_JUMP) {
x86_mov_membase_imm (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, eip), 0, sizeof (mgreg_t));
} else {
x86_mov_reg_membase (code, X86_EAX, X86_EBP, caller_ip_offset, sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, eip), X86_EAX, sizeof (mgreg_t));
}
/* method */
if ((tramp_type == MONO_TRAMPOLINE_JIT) || (tramp_type == MONO_TRAMPOLINE_JUMP)) {
x86_mov_reg_membase (code, X86_EAX, X86_EBP, arg_offset, sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, method), X86_EAX, sizeof (mgreg_t));
} else {
x86_mov_membase_imm (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, method), 0, sizeof (mgreg_t));
}
/* esp */
x86_mov_reg_membase (code, X86_EAX, X86_EBP, regarray_offset + (X86_ESP * sizeof (mgreg_t)), sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, esp), X86_EAX, sizeof (mgreg_t));
/* callee save registers */
x86_mov_reg_membase (code, X86_EAX, X86_EBP, regarray_offset + (X86_EBX * sizeof (mgreg_t)), sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, ebx), X86_EAX, sizeof (mgreg_t));
x86_mov_reg_membase (code, X86_EAX, X86_EBP, regarray_offset + (X86_EDI * sizeof (mgreg_t)), sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, edi), X86_EAX, sizeof (mgreg_t));
x86_mov_reg_membase (code, X86_EAX, X86_EBP, regarray_offset + (X86_ESI * sizeof (mgreg_t)), sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, esi), X86_EAX, sizeof (mgreg_t));
x86_mov_reg_membase (code, X86_EAX, X86_EBP, regarray_offset + (X86_EBP * sizeof (mgreg_t)), sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, ebp), X86_EAX, sizeof (mgreg_t));
/* Push LMF */
/* get the address of lmf for the current thread */
if (aot) {
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_get_lmf_addr");
x86_call_reg (code, X86_EAX);
} else {
x86_call_code (code, mono_get_lmf_addr);
}
/* lmf->lmf_addr = lmf_addr (%eax) */
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, lmf_addr), X86_EAX, sizeof (mgreg_t));
/* lmf->previous_lmf = *(lmf_addr) */
x86_mov_reg_membase (code, X86_ECX, X86_EAX, 0, sizeof (mgreg_t));
/* Signal to mono_arch_find_jit_info () that this is a trampoline frame */
x86_alu_reg_imm (code, X86_ADD, X86_ECX, 1);
x86_mov_membase_reg (code, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, previous_lmf), X86_ECX, sizeof (mgreg_t));
/* *lmf_addr = lmf */
x86_lea_membase (code, X86_ECX, X86_EBP, lmf_offset);
x86_mov_membase_reg (code, X86_EAX, 0, X86_ECX, sizeof (mgreg_t));
/* Call trampoline function */
/* Arg 1 - registers */
x86_lea_membase (code, X86_EAX, X86_EBP, regarray_offset);
x86_mov_membase_reg (code, X86_ESP, (0 * sizeof (mgreg_t)), X86_EAX, sizeof (mgreg_t));
/* Arg2 - calling code */
if (tramp_type == MONO_TRAMPOLINE_JUMP) {
x86_mov_membase_imm (code, X86_ESP, (1 * sizeof (mgreg_t)), 0, sizeof (mgreg_t));
} else {
x86_mov_reg_membase (code, X86_EAX, X86_EBP, caller_ip_offset, sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_ESP, (1 * sizeof (mgreg_t)), X86_EAX, sizeof (mgreg_t));
}
/* Arg3 - trampoline argument */
x86_mov_reg_membase (code, X86_EAX, X86_EBP, arg_offset, sizeof (mgreg_t));
x86_mov_membase_reg (code, X86_ESP, (2 * sizeof (mgreg_t)), X86_EAX, sizeof (mgreg_t));
/* Arg4 - trampoline address */
// FIXME:
x86_mov_membase_imm (code, X86_ESP, (3 * sizeof (mgreg_t)), 0, sizeof (mgreg_t));
// FIXME:
#ifdef __APPLE__
/* check the stack is aligned after the ret ip is pushed */
/*x86_mov_reg_reg (buf, X86_EDX, X86_ESP, 4);
x86_alu_reg_imm (buf, X86_AND, X86_EDX, 15);
x86_alu_reg_imm (buf, X86_CMP, X86_EDX, 0);
x86_branch_disp (buf, X86_CC_Z, 3, FALSE);
x86_breakpoint (buf);*/
#endif
if (aot) {
char *icall_name = g_strdup_printf ("trampoline_func_%d", tramp_type);
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, icall_name);
x86_call_reg (code, X86_EAX);
} else {
tramp = (guint8*)mono_get_trampoline_func (tramp_type);
x86_call_code (code, tramp);
}
/*
* Overwrite the trampoline argument with the address we need to jump to,
* to free %eax.
*/
x86_mov_membase_reg (code, X86_EBP, arg_offset, X86_EAX, 4);
/* Check for interruptions */
if (aot) {
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_thread_force_interruption_checkpoint");
x86_call_reg (code, X86_EAX);
} else {
x86_call_code (code, (guint8*)mono_thread_force_interruption_checkpoint);
}
/* Restore LMF */
x86_mov_reg_membase (code, X86_EAX, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, lmf_addr), sizeof (mgreg_t));
x86_mov_reg_membase (code, X86_ECX, X86_EBP, lmf_offset + G_STRUCT_OFFSET (MonoLMF, previous_lmf), sizeof (mgreg_t));
x86_alu_reg_imm (code, X86_SUB, X86_ECX, 1);
x86_mov_membase_reg (code, X86_EAX, 0, X86_ECX, sizeof (mgreg_t));
/* Restore registers */
for (i = X86_EAX; i <= X86_EDI; ++i) {
if (i == X86_ESP || i == X86_EBP)
continue;
if (i == X86_EAX && !((tramp_type == MONO_TRAMPOLINE_RESTORE_STACK_PROT) || (tramp_type == MONO_TRAMPOLINE_AOT_PLT)))
continue;
x86_mov_reg_membase (code, i, X86_EBP, regarray_offset + (i * 4), 4);
}
/* Restore frame */
x86_leave (code);
if (MONO_TRAMPOLINE_TYPE_MUST_RETURN (tramp_type)) {
/* Load the value returned by the trampoline */
x86_mov_reg_membase (code, X86_EAX, X86_ESP, 0, 4);
/* The trampoline returns normally, pop the trampoline argument */
x86_alu_reg_imm (code, X86_ADD, X86_ESP, 4);
x86_ret (code);
} else {
/* The trampoline argument is at the top of the stack, and it contains the address we need to branch to */
if (tramp_type == MONO_TRAMPOLINE_HANDLER_BLOCK_GUARD) {
x86_pop_reg (code, X86_EAX);
x86_alu_reg_imm (code, X86_ADD, X86_ESP, 0x8);
x86_jump_reg (code, X86_EAX);
} else {
x86_ret (code);
}
}
nacl_global_codeman_validate (&buf, 256, &code);
g_assert ((code - buf) <= 256);
if (info) {
tramp_name = mono_get_generic_trampoline_name (tramp_type);
*info = mono_tramp_info_create (tramp_name, buf, code - buf, ji, unwind_ops);
g_free (tramp_name);
}
return buf;
}
gpointer
mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
{
guint8 *code, *buf;
int tramp_size = NACL_SIZE (16, kNaClAlignment);
code = buf = mono_global_codeman_reserve (tramp_size);
x86_ret (code);
nacl_global_codeman_validate (&buf, tramp_size, &code);
mono_arch_flush_icache (buf, code - buf);
if (info)
*info = mono_tramp_info_create ("nullified_class_init_trampoline", buf, code - buf, NULL, NULL);
return buf;
}
#define TRAMPOLINE_SIZE 10
gpointer
mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
{
guint8 *code, *buf, *tramp;
tramp = mono_get_trampoline_code (tramp_type);
code = buf = mono_domain_code_reserve_align (domain, TRAMPOLINE_SIZE, NACL_SIZE (4, kNaClAlignment));
x86_push_imm (buf, arg1);
x86_jump_code (buf, tramp);
g_assert ((buf - code) <= TRAMPOLINE_SIZE);
nacl_domain_code_validate (domain, &code, NACL_SIZE (4, kNaClAlignment), &buf);
mono_arch_flush_icache (code, buf - code);
if (code_len)
*code_len = buf - code;
return code;
}
gpointer
mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
{
guint8 *tramp;
guint8 *code, *buf;
guint8 **rgctx_null_jumps;
int tramp_size;
int depth, index;
int i;
gboolean mrgctx;
MonoJumpInfo *ji = NULL;
GSList *unwind_ops = NULL;
unwind_ops = mono_arch_get_cie_program ();
mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
index = MONO_RGCTX_SLOT_INDEX (slot);
if (mrgctx)
index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
for (depth = 0; ; ++depth) {
int size = mono_class_rgctx_get_array_size (depth, mrgctx);
if (index < size - 1)
break;
index -= size - 1;
}
#if defined(__default_codegen__)
tramp_size = (aot ? 64 : 36) + 6 * depth;
#elif defined(__native_client_codegen__)
tramp_size = (aot ? 64 : 36) + 2 * kNaClAlignment +
6 * (depth + kNaClAlignment);
#endif
code = buf = mono_global_codeman_reserve (tramp_size);
rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
/* load vtable/mrgctx ptr */
x86_mov_reg_membase (code, X86_EAX, X86_ESP, 4, 4);
if (!mrgctx) {
/* load rgctx ptr from vtable */
x86_mov_reg_membase (code, X86_EAX, X86_EAX, MONO_STRUCT_OFFSET (MonoVTable, runtime_generic_context), 4);
/* is the rgctx ptr null? */
x86_test_reg_reg (code, X86_EAX, X86_EAX);
/* if yes, jump to actual trampoline */
rgctx_null_jumps [0] = code;
x86_branch8 (code, X86_CC_Z, -1, 1);
}
for (i = 0; i < depth; ++i) {
/* load ptr to next array */
if (mrgctx && i == 0)
x86_mov_reg_membase (code, X86_EAX, X86_EAX, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT, 4);
else
x86_mov_reg_membase (code, X86_EAX, X86_EAX, 0, 4);
/* is the ptr null? */
x86_test_reg_reg (code, X86_EAX, X86_EAX);
/* if yes, jump to actual trampoline */
rgctx_null_jumps [i + 1] = code;
x86_branch8 (code, X86_CC_Z, -1, 1);
}
/* fetch slot */
x86_mov_reg_membase (code, X86_EAX, X86_EAX, sizeof (gpointer) * (index + 1), 4);
/* is the slot null? */
x86_test_reg_reg (code, X86_EAX, X86_EAX);
/* if yes, jump to actual trampoline */
rgctx_null_jumps [depth + 1] = code;
x86_branch8 (code, X86_CC_Z, -1, 1);
/* otherwise return */
x86_ret (code);
for (i = mrgctx ? 1 : 0; i <= depth + 1; ++i)
x86_patch (rgctx_null_jumps [i], code);
g_free (rgctx_null_jumps);
x86_mov_reg_membase (code, MONO_ARCH_VTABLE_REG, X86_ESP, 4, 4);
if (aot) {
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
x86_jump_reg (code, X86_EAX);
} else {
tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), NULL);
/* jump to the actual trampoline */
x86_jump_code (code, tramp);
}
nacl_global_codeman_validate (&buf, tramp_size, &code);
mono_arch_flush_icache (buf, code - buf);
g_assert (code - buf <= tramp_size);
if (info) {
char *name = mono_get_rgctx_fetch_trampoline_name (slot);
*info = mono_tramp_info_create (name, buf, code - buf, ji, unwind_ops);
g_free (name);
}
return buf;
}
/*
* mono_arch_create_general_rgctx_lazy_fetch_trampoline:
*
* This is a general variant of the rgctx fetch trampolines. It receives a pointer to gpointer[2] in the rgctx reg. The first entry contains the slot, the second
* the trampoline to call if the slot is not filled.
*/
gpointer
mono_arch_create_general_rgctx_lazy_fetch_trampoline (MonoTrampInfo **info, gboolean aot)
{
guint8 *code, *buf;
int tramp_size;
MonoJumpInfo *ji = NULL;
GSList *unwind_ops = NULL;
g_assert (aot);
unwind_ops = mono_arch_get_cie_program ();
tramp_size = 64;
code = buf = mono_global_codeman_reserve (tramp_size);
// FIXME: Currently, we always go to the slow path.
/* Load trampoline addr */
x86_mov_reg_membase (code, X86_EAX, MONO_ARCH_RGCTX_REG, 4, 4);
/* Load mrgctx/vtable */
x86_mov_reg_membase (code, MONO_ARCH_VTABLE_REG, X86_ESP, 4, 4);
x86_jump_reg (code, X86_EAX);
nacl_global_codeman_validate (&buf, tramp_size, &code);
mono_arch_flush_icache (buf, code - buf);
g_assert (code - buf <= tramp_size);
if (info)
*info = mono_tramp_info_create ("rgctx_fetch_trampoline_general", buf, code - buf, ji, unwind_ops);
return buf;
}
gpointer
mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
{
guint8 *tramp;
guint8 *code, *buf;
static int byte_offset = -1;
static guint8 bitmask;
guint8 *jump;
int tramp_size;
GSList *unwind_ops = NULL;
MonoJumpInfo *ji = NULL;
tramp_size = 64;
code = buf = mono_global_codeman_reserve (tramp_size);
unwind_ops = mono_arch_get_cie_program ();
if (byte_offset < 0)
mono_marshal_find_bitfield_offset (MonoVTable, initialized, &byte_offset, &bitmask);
x86_test_membase_imm (code, MONO_ARCH_VTABLE_REG, byte_offset, bitmask);
jump = code;
x86_branch8 (code, X86_CC_Z, -1, 1);
x86_ret (code);
x86_patch (jump, code);
/* Push the vtable so the stack is the same as in a specific trampoline */
x86_push_reg (code, MONO_ARCH_VTABLE_REG);
if (aot) {
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "generic_trampoline_generic_class_init");
x86_jump_reg (code, X86_EAX);
} else {
tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_GENERIC_CLASS_INIT);
/* jump to the actual trampoline */
x86_jump_code (code, tramp);
}
mono_arch_flush_icache (code, code - buf);
g_assert (code - buf <= tramp_size);
#ifdef __native_client_codegen__
g_assert (code - buf <= kNaClAlignment);
#endif
nacl_global_codeman_validate (&buf, tramp_size, &code);
if (info)
*info = mono_tramp_info_create ("generic_class_init_trampoline", buf, code - buf, ji, unwind_ops);
return buf;
}
#ifdef MONO_ARCH_MONITOR_OBJECT_REG
/*
* The code produced by this trampoline is equivalent to this:
*
* if (obj) {
* if (obj->synchronisation) {
* if (obj->synchronisation->owner == 0) {
* if (cmpxch (&obj->synchronisation->owner, TID, 0) == 0)
* return;
* }
* if (obj->synchronisation->owner == TID) {
* ++obj->synchronisation->nest;
* return;
* }
* }
* }
* return full_monitor_enter ();
*
*/
gpointer
mono_arch_create_monitor_enter_trampoline (MonoTrampInfo **info, gboolean aot)
{
guint8 *tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_MONITOR_ENTER);
guint8 *code, *buf;
guint8 *jump_obj_null, *jump_sync_null, *jump_other_owner, *jump_cmpxchg_failed, *jump_tid, *jump_sync_thin_hash = NULL;
int tramp_size;
int owner_offset, nest_offset, dummy;
MonoJumpInfo *ji = NULL;
GSList *unwind_ops = NULL;
g_assert (MONO_ARCH_MONITOR_OBJECT_REG == X86_EAX);
mono_monitor_threads_sync_members_offset (&owner_offset, &nest_offset, &dummy);
g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (owner_offset) == sizeof (gpointer));
g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (nest_offset) == sizeof (guint32));
owner_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (owner_offset);
nest_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (nest_offset);
tramp_size = NACL_SIZE (96, 128);
code = buf = mono_global_codeman_reserve (tramp_size);
if (mono_thread_get_tls_offset () != -1) {
/* MonoObject* obj is in EAX */
/* is obj null? */
x86_test_reg_reg (code, X86_EAX, X86_EAX);
/* if yes, jump to actual trampoline */
jump_obj_null = code;
x86_branch8 (code, X86_CC_Z, -1, 1);
/* load obj->synchronization to ECX */
x86_mov_reg_membase (code, X86_ECX, X86_EAX, MONO_STRUCT_OFFSET (MonoObject, synchronisation), 4);
if (mono_gc_is_moving ()) {
/*if bit zero is set it's a thin hash*/
/*FIXME use testb encoding*/
x86_test_reg_imm (code, X86_ECX, 0x01);
jump_sync_thin_hash = code;
x86_branch8 (code, X86_CC_NE, -1, 1);
/*clear bits used by the gc*/
x86_alu_reg_imm (code, X86_AND, X86_ECX, ~0x3);
}
/* is synchronization null? */
x86_test_reg_reg (code, X86_ECX, X86_ECX);
/* if yes, jump to actual trampoline */
jump_sync_null = code;
x86_branch8 (code, X86_CC_Z, -1, 1);
/* load MonoInternalThread* into EDX */
if (aot) {
/* load_aotconst () puts the result into EAX */
x86_mov_reg_reg (code, X86_EDX, X86_EAX, sizeof (mgreg_t));
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_TLS_OFFSET, GINT_TO_POINTER (TLS_KEY_THREAD));
code = mono_x86_emit_tls_get_reg (code, X86_EAX, X86_EAX);
x86_xchg_reg_reg (code, X86_EAX, X86_EDX, sizeof (mgreg_t));
} else {
code = mono_x86_emit_tls_get (code, X86_EDX, mono_thread_get_tls_offset ());
}
/* load TID into EDX */
x86_mov_reg_membase (code, X86_EDX, X86_EDX, MONO_STRUCT_OFFSET (MonoInternalThread, tid), 4);
/* is synchronization->owner null? */
x86_alu_membase_imm (code, X86_CMP, X86_ECX, owner_offset, 0);
/* if not, jump to next case */
jump_tid = code;
x86_branch8 (code, X86_CC_NZ, -1, 1);
/* if yes, try a compare-exchange with the TID */
/* free up register EAX, needed for the zero */
x86_push_reg (code, X86_EAX);
/* zero EAX */
x86_alu_reg_reg (code, X86_XOR, X86_EAX, X86_EAX);
/* compare and exchange */
x86_prefix (code, X86_LOCK_PREFIX);
x86_cmpxchg_membase_reg (code, X86_ECX, owner_offset, X86_EDX);
/* if not successful, jump to actual trampoline */
jump_cmpxchg_failed = code;
x86_branch8 (code, X86_CC_NZ, -1, 1);
/* if successful, pop and return */
x86_pop_reg (code, X86_EAX);
x86_ret (code);
/* next case: synchronization->owner is not null */
x86_patch (jump_tid, code);
/* is synchronization->owner == TID? */
x86_alu_membase_reg (code, X86_CMP, X86_ECX, owner_offset, X86_EDX);
/* if not, jump to actual trampoline */
jump_other_owner = code;
x86_branch8 (code, X86_CC_NZ, -1, 1);
/* if yes, increment nest */
x86_inc_membase (code, X86_ECX, nest_offset);
/* return */
x86_ret (code);
/* push obj */
x86_patch (jump_obj_null, code);
if (jump_sync_thin_hash)
x86_patch (jump_sync_thin_hash, code);
x86_patch (jump_sync_null, code);
x86_patch (jump_other_owner, code);
x86_push_reg (code, X86_EAX);
/* jump to the actual trampoline */
x86_patch (jump_cmpxchg_failed, code);
if (aot) {
/* We are calling the generic trampoline directly, the argument is pushed
* on the stack just like a specific trampoline.
*/
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "generic_trampoline_monitor_enter");
x86_jump_reg (code, X86_EAX);
} else {
x86_jump_code (code, tramp);
}
} else {
/* push obj and jump to the actual trampoline */
x86_push_reg (code, X86_EAX);
if (aot) {
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "generic_trampoline_monitor_enter");
x86_jump_reg (code, X86_EAX);
} else {
x86_jump_code (code, tramp);
}
}
mono_arch_flush_icache (buf, code - buf);
g_assert (code - buf <= tramp_size);
nacl_global_codeman_validate (&buf, tramp_size, &code);
if (info)
*info = mono_tramp_info_create ("monitor_enter_trampoline", buf, code - buf, ji, unwind_ops);
return buf;
}
gpointer
mono_arch_create_monitor_exit_trampoline (MonoTrampInfo **info, gboolean aot)
{
guint8 *tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_MONITOR_EXIT);
guint8 *code, *buf;
guint8 *jump_obj_null, *jump_have_waiters, *jump_sync_null, *jump_not_owned, *jump_sync_thin_hash = NULL;
guint8 *jump_next;
int tramp_size;
int owner_offset, nest_offset, entry_count_offset;
MonoJumpInfo *ji = NULL;
GSList *unwind_ops = NULL;
g_assert (MONO_ARCH_MONITOR_OBJECT_REG == X86_EAX);
mono_monitor_threads_sync_members_offset (&owner_offset, &nest_offset, &entry_count_offset);
g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (owner_offset) == sizeof (gpointer));
g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (nest_offset) == sizeof (guint32));
g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (entry_count_offset) == sizeof (gint32));
owner_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (owner_offset);
nest_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (nest_offset);
entry_count_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (entry_count_offset);
tramp_size = NACL_SIZE (96, 128);
code = buf = mono_global_codeman_reserve (tramp_size);
if (mono_thread_get_tls_offset () != -1) {
/* MonoObject* obj is in EAX */
/* is obj null? */
x86_test_reg_reg (code, X86_EAX, X86_EAX);
/* if yes, jump to actual trampoline */
jump_obj_null = code;
x86_branch8 (code, X86_CC_Z, -1, 1);
/* load obj->synchronization to ECX */
x86_mov_reg_membase (code, X86_ECX, X86_EAX, MONO_STRUCT_OFFSET (MonoObject, synchronisation), 4);
if (mono_gc_is_moving ()) {
/*if bit zero is set it's a thin hash*/
/*FIXME use testb encoding*/
x86_test_reg_imm (code, X86_ECX, 0x01);
jump_sync_thin_hash = code;
x86_branch8 (code, X86_CC_NE, -1, 1);
/*clear bits used by the gc*/
x86_alu_reg_imm (code, X86_AND, X86_ECX, ~0x3);
}
/* is synchronization null? */
x86_test_reg_reg (code, X86_ECX, X86_ECX);
/* if yes, jump to actual trampoline */
jump_sync_null = code;
x86_branch8 (code, X86_CC_Z, -1, 1);
/* next case: synchronization is not null */
/* load MonoInternalThread* into EDX */
if (aot) {
/* load_aotconst () puts the result into EAX */
x86_mov_reg_reg (code, X86_EDX, X86_EAX, sizeof (mgreg_t));
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_TLS_OFFSET, GINT_TO_POINTER (TLS_KEY_THREAD));
code = mono_x86_emit_tls_get_reg (code, X86_EAX, X86_EAX);
x86_xchg_reg_reg (code, X86_EAX, X86_EDX, sizeof (mgreg_t));
} else {
code = mono_x86_emit_tls_get (code, X86_EDX, mono_thread_get_tls_offset ());
}
/* load TID into EDX */
x86_mov_reg_membase (code, X86_EDX, X86_EDX, MONO_STRUCT_OFFSET (MonoInternalThread, tid), 4);
/* is synchronization->owner == TID */
x86_alu_membase_reg (code, X86_CMP, X86_ECX, owner_offset, X86_EDX);
/* if no, jump to actual trampoline */
jump_not_owned = code;
x86_branch8 (code, X86_CC_NZ, -1, 1);
/* next case: synchronization->owner == TID */
/* is synchronization->nest == 1 */
x86_alu_membase_imm (code, X86_CMP, X86_ECX, nest_offset, 1);
/* if not, jump to next case */
jump_next = code;
x86_branch8 (code, X86_CC_NZ, -1, 1);
/* if yes, is synchronization->entry_count zero? */
x86_alu_membase_imm (code, X86_CMP, X86_ECX, entry_count_offset, 0);
/* if not, jump to actual trampoline */
jump_have_waiters = code;
x86_branch8 (code, X86_CC_NZ, -1 , 1);
/* if yes, set synchronization->owner to null and return */
x86_mov_membase_imm (code, X86_ECX, owner_offset, 0, 4);
x86_ret (code);
/* next case: synchronization->nest is not 1 */
x86_patch (jump_next, code);
/* decrease synchronization->nest and return */
x86_dec_membase (code, X86_ECX, nest_offset);
x86_ret (code);
/* push obj and jump to the actual trampoline */
x86_patch (jump_obj_null, code);
if (jump_sync_thin_hash)
x86_patch (jump_sync_thin_hash, code);
x86_patch (jump_have_waiters, code);
x86_patch (jump_not_owned, code);
x86_patch (jump_sync_null, code);
}
/* push obj and jump to the actual trampoline */
x86_push_reg (code, X86_EAX);
if (aot) {
code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "generic_trampoline_monitor_exit");
x86_jump_reg (code, X86_EAX);
} else {
x86_jump_code (code, tramp);
}
nacl_global_codeman_validate (&buf, tramp_size, &code);
mono_arch_flush_icache (buf, code - buf);
g_assert (code - buf <= tramp_size);
if (info)
*info = mono_tramp_info_create ("monitor_exit_trampoline", buf, code - buf, ji, unwind_ops);
return buf;
}
#else
gpointer
mono_arch_create_monitor_enter_trampoline (MonoTrampInfo **info, gboolean aot)
{
g_assert_not_reached ();
return NULL;
}
gpointer
mono_arch_create_monitor_exit_trampoline (MonoTrampInfo **info, gboolean aot)
{
g_assert_not_reached ();
return NULL;
}
#endif
void
mono_arch_invalidate_method (MonoJitInfo *ji, void *func, gpointer func_arg)
{
/* FIXME: This is not thread safe */
guint8 *code = ji->code_start;
x86_push_imm (code, func_arg);
x86_call_code (code, (guint8*)func);
}
static gpointer
handler_block_trampoline_helper (void)
{
MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
return jit_tls->handler_block_return_address;
}
gpointer
mono_arch_create_handler_block_trampoline (MonoTrampInfo **info, gboolean aot)
{
guint8 *tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_HANDLER_BLOCK_GUARD);
guint8 *code, *buf;
int tramp_size = 64;
MonoJumpInfo *ji = NULL;
GSList *unwind_ops = NULL;
g_assert (!aot);
code = buf = mono_global_codeman_reserve (tramp_size);
/*
This trampoline restore the call chain of the handler block then jumps into the code that deals with it.
*/
/*
* We are in a method frame after the call emitted by OP_CALL_HANDLER.
*/
if (mono_get_jit_tls_offset () != -1) {
code = mono_x86_emit_tls_get (code, X86_EAX, mono_get_jit_tls_offset ());
x86_mov_reg_membase (code, X86_EAX, X86_EAX, MONO_STRUCT_OFFSET (MonoJitTlsData, handler_block_return_address), 4);
} else {
/*Slow path uses a c helper*/
x86_call_code (code, handler_block_trampoline_helper);
}
/* Simulate a call */
/*Fix stack alignment*/
x86_alu_reg_imm (code, X86_SUB, X86_ESP, 0x4);
/* This is the address the trampoline will return to */
x86_push_reg (code, X86_EAX);
/* Dummy trampoline argument, since we call the generic trampoline directly */
x86_push_imm (code, 0);
x86_jump_code (code, tramp);
nacl_global_codeman_validate (&buf, tramp_size, &code);
mono_arch_flush_icache (buf, code - buf);
g_assert (code - buf <= tramp_size);
if (info)
*info = mono_tramp_info_create ("handler_block_trampoline", buf, code - buf, ji, unwind_ops);
return buf;
}
guint8*
mono_arch_get_call_target (guint8 *code)
{
if (code [-5] == 0xe8) {
gint32 disp = *(gint32*)(code - 4);
guint8 *target = code + disp;
return target;
} else {
return NULL;
}
}
guint32
mono_arch_get_plt_info_offset (guint8 *plt_entry, mgreg_t *regs, guint8 *code)
{
return *(guint32*)(plt_entry + NACL_SIZE (6, 12));
}
/*
* mono_arch_get_gsharedvt_arg_trampoline:
*
* Return a trampoline which passes ARG to the gsharedvt in/out trampoline ADDR.
*/
gpointer
mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpointer addr)
{
guint8 *code, *start;
int buf_len;
buf_len = 10;
start = code = mono_domain_code_reserve (domain, buf_len);
x86_mov_reg_imm (code, X86_EAX, arg);
x86_jump_code (code, addr);
g_assert ((code - start) <= buf_len);
nacl_domain_code_validate (domain, &start, buf_len, &code);
mono_arch_flush_icache (start, code - start);
return start;
}
#if defined(ENABLE_GSHAREDVT)
#include "../../../mono-extensions/mono/mini/tramp-x86-gsharedvt.c"
#else
gpointer
mono_arch_get_gsharedvt_trampoline (MonoTrampInfo **info, gboolean aot)
{
if (info)
*info = NULL;
return NULL;
}
#endif /* !MONOTOUCH */