Merge pull request #409 from Alkarex/patch-1

[mono.git] / mono / mini / unwind.c

diff --git a/mono/mini/unwind.c b/mono/mini/unwind.c
index dba0ed7155597773d801c2147d3424234117566e..2377e0dd009b5e970a01d2732dc2584f943e4458 100644 (file)
--- a/mono/mini/unwind.c
+++ b/mono/mini/unwind.c
@@ -12,6 +12,7 @@
 
 #include <mono/utils/mono-counters.h>
 #include <mono/utils/freebsd-dwarf.h>
+#include <mono/utils/hazard-pointer.h>
 #include <mono/metadata/threads-types.h>
 #include <mono/metadata/mono-endian.h>
 
@@ -34,6 +35,7 @@ static CRITICAL_SECTION unwind_mutex;
 
 static MonoUnwindInfo **cached_info;
 static int cached_info_next, cached_info_size;
+static GSList *cached_info_list;
 /* Statistics */
 static int unwind_info_size;
 
@@ -52,7 +54,16 @@ static int map_hw_reg_to_dwarf_reg [] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
 #define DWARF_DATA_ALIGN (-4)
 #define DWARF_PC_REG (mono_hw_reg_to_dwarf_reg (ARMREG_LR))
 #elif defined (TARGET_X86)
+#ifdef __APPLE__
+/*
+ * LLVM seems to generate unwind info where esp is encoded as 5, and ebp as 4, ie see this line:
+ *   def ESP : RegisterWithSubRegs<"esp", [SP]>, DwarfRegNum<[-2, 5, 4]>;
+ * in lib/Target/X86/X86RegisterInfo.td in the llvm sources.
+ */
+static int map_hw_reg_to_dwarf_reg [] = { 0, 1, 2, 3, 5, 4, 6, 7, 8 };
+#else
 static int map_hw_reg_to_dwarf_reg [] = { 0, 1, 2, 3, 4, 5, 6, 7, 8 };
+#endif
 /* + 1 is for IP */
 #define NUM_REGS X86_NREG + 1
 #define DWARF_DATA_ALIGN (-4)
@@ -71,6 +82,17 @@ static int map_hw_reg_to_dwarf_reg [] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
 #define NUM_REGS 16
 #define DWARF_DATA_ALIGN (-8)
 #define DWARF_PC_REG (mono_hw_reg_to_dwarf_reg (14))
+#elif defined (TARGET_MIPS)
+/* FIXME: */
+static int map_hw_reg_to_dwarf_reg [32] = {
+       0, 1, 2, 3, 4, 5, 6, 7,
+       8, 9, 10, 11, 12, 13, 14, 15,
+       16, 17, 18, 19, 20, 21, 22, 23,
+       24, 25, 26, 27, 28, 29, 30, 31
+};
+#define NUM_REGS 32
+#define DWARF_DATA_ALIGN (-(gint32)sizeof (mgreg_t))
+#define DWARF_PC_REG (mono_hw_reg_to_dwarf_reg (mips_ra))
 #else
 static int map_hw_reg_to_dwarf_reg [16];
 #define NUM_REGS 16
@@ -481,8 +503,8 @@ mono_cache_unwind_info (guint8 *unwind_info, guint32 unwind_info_len)
                MonoUnwindInfo **old_table, **new_table;
 
                /*
-                * Have to resize the table, while synchronizing with 
-                * mono_get_cached_unwind_info () using hazard pointers.
+                * Avoid freeing the old table so mono_get_cached_unwind_info ()
+                * doesn't need locks/hazard pointers.
                 */
 
                old_table = cached_info;
@@ -494,9 +516,7 @@ mono_cache_unwind_info (guint8 *unwind_info, guint32 unwind_info_len)
 
                cached_info = new_table;
 
-               mono_memory_barrier ();
-
-               mono_thread_hazardous_free_or_queue (old_table, g_free);
+               cached_info_list = g_slist_prepend (cached_info_list, cached_info);
 
                cached_info_size *= 2;
        }
@@ -509,32 +529,6 @@ mono_cache_unwind_info (guint8 *unwind_info, guint32 unwind_info_len)
        return i;
 }
 
-static gpointer
-get_hazardous_pointer (gpointer volatile *pp, MonoThreadHazardPointers *hp, int hazard_index)
-{
-       gpointer p;
-
-       for (;;) {
-               /* Get the pointer */
-               p = *pp;
-               /* If we don't have hazard pointers just return the
-                  pointer. */
-               if (!hp)
-                       return p;
-               /* Make it hazardous */
-               mono_hazard_pointer_set (hp, hazard_index, p);
-               /* Check that it's still the same.  If not, try
-                  again. */
-               if (*pp != p) {
-                       mono_hazard_pointer_clear (hp, hazard_index);
-                       continue;
-               }
-               break;
-       }
-
-       return p;
-}
-
 /*
  * This function is signal safe.
  */
@@ -544,17 +538,18 @@ mono_get_cached_unwind_info (guint32 index, guint32 *unwind_info_len)
        MonoUnwindInfo **table;
        MonoUnwindInfo *info;
        guint8 *data;
-       MonoThreadHazardPointers *hp = mono_hazard_pointer_get ();
 
-       table = get_hazardous_pointer ((gpointer volatile*)&cached_info, hp, 0);
+       /*
+        * This doesn't need any locks/hazard pointers,
+        * since new tables are copies of the old ones.
+        */
+       table = cached_info;
 
        info = table [index];
 
        *unwind_info_len = info->len;
        data = info->info;
 
-       mono_hazard_pointer_clear (hp, 0);
-
        return data;
 }
 
@@ -611,6 +606,10 @@ decode_cie_op (guint8 *p, guint8 **endp)
                case DW_CFA_advance_loc4:
                        p += 4;
                        break;
+               case DW_CFA_offset_extended_sf:
+                       decode_uleb128 (p, &p);
+                       decode_uleb128 (p, &p);
+                       break;
                default:
                        g_assert_not_reached ();
                }
@@ -623,24 +622,6 @@ decode_cie_op (guint8 *p, guint8 **endp)
        *endp = p;
 }
 
-/* Pointer Encoding in the .eh_frame */
-enum {
-       DW_EH_PE_absptr = 0x00,
-       DW_EH_PE_omit = 0xff,
-
-       DW_EH_PE_udata4 = 0x03,
-       DW_EH_PE_sdata4 = 0x0b,
-       DW_EH_PE_sdata8 = 0x0c,
-
-       DW_EH_PE_pcrel = 0x10,
-       DW_EH_PE_textrel = 0x20,
-       DW_EH_PE_datarel = 0x30,
-       DW_EH_PE_funcrel = 0x40,
-       DW_EH_PE_aligned = 0x50,
-
-       DW_EH_PE_indirect = 0x80
-};
-
 static gint64
 read_encoded_val (guint32 encoding, guint8 *p, guint8 **endp)
 {
@@ -767,6 +748,9 @@ decode_lsda (guint8 *lsda, guint8 *code, MonoJitExceptionInfo **ex_info, guint32
                p += sizeof (gint32);
                action_offset = decode_uleb128 (p, &p);
 
+               if (!action_offset)
+                       continue;
+
                action = action_table + action_offset - 1;
 
                type_offset = decode_sleb128 (action, &action);