mono/utils/mach-support-amd64.c

   1 /*
   2  * mach-support-x86.c: mach support for x86
   3  *
   4  * Authors:
   5  *   Geoff Norton (gnorton@novell.com)
   6  *   Rodrigo Kumpera (kumpera@gmail.com)
   7  *
   8  * (C) 2010 Novell, Inc.
   9  * (C) 2013 Xamarin, Inc.
  10  */
  11
  12 #include <config.h>
  13
  14 #if defined(__MACH__)
  15 #include <stdint.h>
  16 #include <glib.h>
  17 #include <pthread.h>
  18 #include "utils/mono-sigcontext.h"
  19 #include "mach-support.h"
  20
  21 //For reg numbers
  22 #include <mono/arch/amd64/amd64-codegen.h>
  23
  24 /* Known offsets used for TLS storage*/
  25
  26 /* All OSX versions up to 10.8 */
  27 #define TLS_VECTOR_OFFSET_CATS 0x60
  28 #define TLS_VECTOR_OFFSET_10_9 0xe0
  29 #define TLS_VECTOR_OFFSET_10_11 0x100
  30
  31 /* This is 2 slots less than the known low */
  32 #define TLS_PROBE_LOW_WATERMARK 0x50
  33 /* This is 28 slots above the know high, which is more than the known high-low*/
  34 #define TLS_PROBE_HIGH_WATERMARK 0x200
  35
  36
  37 static int tls_vector_offset;
  38
  39 void *
  40 mono_mach_arch_get_ip (thread_state_t state)
  41 {
  42         x86_thread_state64_t *arch_state = (x86_thread_state64_t *) state;
  43
  44         return (void *) arch_state->__rip;
  45 }
  46
  47 void *
  48 mono_mach_arch_get_sp (thread_state_t state)
  49 {
  50         x86_thread_state64_t *arch_state = (x86_thread_state64_t *) state;
  51
  52         return (void *) arch_state->__rsp;
  53 }
  54
  55 int
  56 mono_mach_arch_get_mcontext_size ()
  57 {
  58         return sizeof (struct __darwin_mcontext64);
  59 }
  60
  61 void
  62 mono_mach_arch_thread_state_to_mcontext (thread_state_t state, void *context)
  63 {
  64         x86_thread_state64_t *arch_state = (x86_thread_state64_t *) state;
  65         struct __darwin_mcontext64 *ctx = (struct __darwin_mcontext64 *) context;
  66
  67         ctx->__ss = *arch_state;
  68 }
  69
  70 void
  71 mono_mach_arch_mcontext_to_thread_state (void *context, thread_state_t state)
  72 {
  73         x86_thread_state64_t *arch_state = (x86_thread_state64_t *) state;
  74         struct __darwin_mcontext64 *ctx = (struct __darwin_mcontext64 *) context;
  75
  76         *arch_state = ctx->__ss;
  77 }
  78
  79 void
  80 mono_mach_arch_thread_state_to_mono_context (thread_state_t state, MonoContext *context)
  81 {
  82         x86_thread_state64_t *arch_state = (x86_thread_state64_t *) state;
  83         context->gregs [AMD64_RAX] = arch_state->__rax;
  84         context->gregs [AMD64_RBX] = arch_state->__rbx;
  85         context->gregs [AMD64_RCX] = arch_state->__rcx;
  86         context->gregs [AMD64_RDX] = arch_state->__rdx;
  87         context->gregs [AMD64_RDI] = arch_state->__rdi;
  88         context->gregs [AMD64_RBP] = arch_state->__rbp;
  89         context->gregs [AMD64_RSP] = arch_state->__rsp;
  90         context->gregs [AMD64_R8] = arch_state->__r8;
  91         context->gregs [AMD64_R9] = arch_state->__r9;
  92         context->gregs [AMD64_R10] = arch_state->__r10;
  93         context->gregs [AMD64_R11] = arch_state->__r11;
  94         context->gregs [AMD64_R12] = arch_state->__r12;
  95         context->gregs [AMD64_R13] = arch_state->__r13;
  96         context->gregs [AMD64_R14] = arch_state->__r14;
  97         context->gregs [AMD64_R15] = arch_state->__r15;
  98         context->gregs [AMD64_RIP] = arch_state->__rip;
  99 }
 100
 101 int
 102 mono_mach_arch_get_thread_state_size ()
 103 {
 104         return sizeof (x86_thread_state64_t);
 105 }
 106
 107 kern_return_t
 108 mono_mach_arch_get_thread_state (thread_port_t thread, thread_state_t state, mach_msg_type_number_t *count)
 109 {
 110         x86_thread_state64_t *arch_state = (x86_thread_state64_t *) state;
 111         kern_return_t ret;
 112
 113         *count = x86_THREAD_STATE64_COUNT;
 114
 115         ret = thread_get_state (thread, x86_THREAD_STATE64, (thread_state_t) arch_state, count);
 116
 117         return ret;
 118 }
 119
 120 kern_return_t
 121 mono_mach_arch_set_thread_state (thread_port_t thread, thread_state_t state, mach_msg_type_number_t count)
 122 {
 123         return thread_set_state (thread, x86_THREAD_STATE64, state, count);
 124 }
 125
 126 void *
 127 mono_mach_get_tls_address_from_thread (pthread_t thread, pthread_key_t key)
 128 {
 129         /* OSX stores TLS values in a hidden array inside the pthread_t structure
 130          * They are keyed off a giant array from a known offset into the pointer.  This value
 131          * is baked into their pthread_getspecific implementation
 132          */
 133         intptr_t *p = (intptr_t *)thread;
 134         intptr_t **tsd = (intptr_t **) ((char*)p + tls_vector_offset);
 135         g_assert (tls_vector_offset != -1);
 136
 137         return (void *) &tsd [key];
 138 }
 139
 140 void *
 141 mono_mach_arch_get_tls_value_from_thread (pthread_t thread, guint32 key)
 142 {
 143         return *(void**)mono_mach_get_tls_address_from_thread (thread, key);
 144 }
 145
 146 void
 147 mono_mach_init (pthread_key_t key)
 148 {
 149         int i;
 150         void *old_value = pthread_getspecific (key);
 151         void *canary = (void*)0xDEADBEEFu;
 152
 153         pthread_key_create (&key, NULL);
 154         g_assert (old_value != canary);
 155
 156         pthread_setspecific (key, canary);
 157
 158         /*First we probe for cats*/
 159         tls_vector_offset = TLS_VECTOR_OFFSET_CATS;
 160         if (mono_mach_arch_get_tls_value_from_thread (pthread_self (), key) == canary)
 161                 goto ok;
 162
 163         tls_vector_offset = TLS_VECTOR_OFFSET_10_9;
 164         if (mono_mach_arch_get_tls_value_from_thread (pthread_self (), key) == canary)
 165                 goto ok;
 166
 167         tls_vector_offset = TLS_VECTOR_OFFSET_10_11;
 168         if (mono_mach_arch_get_tls_value_from_thread (pthread_self (), key) == canary)
 169                 goto ok;
 170
 171         /*Fallback to scanning a large range of offsets*/
 172         for (i = TLS_PROBE_LOW_WATERMARK; i <= TLS_PROBE_HIGH_WATERMARK; i += 4) {
 173                 tls_vector_offset = i;
 174                 if (mono_mach_arch_get_tls_value_from_thread (pthread_self (), key) == canary) {
 175                         g_warning ("Found new TLS offset at %d", i);
 176                         goto ok;
 177                 }
 178         }
 179
 180         tls_vector_offset = -1;
 181         g_warning ("could not discover the mach TLS offset");
 182 ok:
 183         pthread_setspecific (key, old_value);
 184 }
 185
 186 #endif