X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;f=mono%2Fmini%2Funwind.c;h=72f5d0d59e0b959373fcb1cb00dee5b86b4b601d;hb=HEAD;hp=2dc04322dc6b22a1f64feac6342fa85d39e5f334;hpb=a3304910e9e08ec965fb06ef6fa4a19257dddf8c;p=mono.git

diff --git a/mono/mini/unwind.c b/mono/mini/unwind.c
index 2dc04322dc6..72f5d0d59e0 100644
--- a/mono/mini/unwind.c
+++ b/mono/mini/unwind.c
@@ -867,9 +867,10 @@ read_encoded_val (guint32 encoding, guint8 *p, guint8 **endp)
  * decode_lsda:
  *
  *   Decode the Mono specific Language Specific Data Area generated by LLVM.
+ * This function is async safe.
  */
 static void
-decode_lsda (guint8 *lsda, guint8 *code, MonoJitExceptionInfo **ex_info, guint32 *ex_info_len, gpointer **type_info, int *this_reg, int *this_offset)
+decode_lsda (guint8 *lsda, guint8 *code, MonoJitExceptionInfo *ex_info, gpointer *type_info, guint32 *ex_info_len, int *this_reg, int *this_offset)
 {
 	guint8 *p;
 	int i, ncall_sites, this_encoding;
@@ -905,12 +906,8 @@ decode_lsda (guint8 *lsda, guint8 *code, MonoJitExceptionInfo **ex_info, guint32
 	ncall_sites = decode_uleb128 (p, &p);
 	p = (guint8*)ALIGN_TO ((mgreg_t)p, 4);
 
-	if (ex_info) {
-		*ex_info = (MonoJitExceptionInfo *)g_malloc0 (ncall_sites * sizeof (MonoJitExceptionInfo));
+	if (ex_info_len)
 		*ex_info_len = ncall_sites;
-	}
-	if (type_info)
-		*type_info = (gpointer *)g_malloc0 (ncall_sites * sizeof (gpointer));
 
 	for (i = 0; i < ncall_sites; ++i) {
 		int block_start_offset, block_size, landing_pad;
@@ -930,11 +927,11 @@ decode_lsda (guint8 *lsda, guint8 *code, MonoJitExceptionInfo **ex_info, guint32
 		//printf ("X: %p %d\n", landing_pad, *(int*)tinfo);
 
 		if (ex_info) {
-			if (*type_info)
-				(*type_info) [i] = tinfo;
-			(*ex_info)[i].try_start = code + block_start_offset;
-			(*ex_info)[i].try_end = code + block_start_offset + block_size;
-			(*ex_info)[i].handler_start = code + landing_pad;
+			if (type_info)
+				type_info [i] = tinfo;
+			ex_info[i].try_start = code + block_start_offset;
+			ex_info[i].try_end = code + block_start_offset + block_size;
+			ex_info[i].handler_start = code + landing_pad;
 		}
 	}
 }
@@ -1073,7 +1070,16 @@ mono_unwind_decode_fde (guint8 *fde, guint32 *out_len, guint32 *code_len, MonoJi
 		if (lsda_offset != 0) {
 			lsda = fde_aug + lsda_offset;
 
-			decode_lsda (lsda, code, ex_info, ex_info_len, type_info, this_reg, this_offset);
+			/* Get the lengths first */
+			guint32 len;
+			decode_lsda (lsda, code, NULL, NULL, &len, this_reg, this_offset);
+
+			if (ex_info)
+				*ex_info = (MonoJitExceptionInfo *)g_malloc0 (len * sizeof (MonoJitExceptionInfo));
+			if (type_info)
+				*type_info = (gpointer *)g_malloc0 (len * sizeof (gpointer));
+
+			decode_lsda (lsda, code, ex_info ? *ex_info : NULL, type_info ? *type_info : NULL, ex_info_len, this_reg, this_offset);
 		}
 	}
 
@@ -1116,13 +1122,15 @@ mono_unwind_decode_fde (guint8 *fde, guint32 *out_len, guint32 *code_len, MonoJi
  * mono_unwind_decode_mono_fde:
  *
  *   Decode an FDE entry in the LLVM emitted mono EH frame.
- * info->ex_info is set to a malloc-ed array of MonoJitExceptionInfo structures,
- * only try_start, try_end and handler_start is set.
- * info->type_info is set to a malloc-ed array containing the ttype table from the
- * LSDA.
+ * If EI/TYPE_INFO/UNW_INFO are NULL, compute only the value of the scalar fields in INFO.
+ * Otherwise:
+ * - Fill out EX_INFO with try_start, try_end and handler_start.
+ * - Fill out TYPE_INFO with the ttype table from the LSDA.
+ * - Fill out UNW_INFO with the unwind info.
+ * This function is async safe.
  */
 void
-mono_unwind_decode_llvm_mono_fde (guint8 *fde, int fde_len, guint8 *cie, guint8 *code, MonoLLVMFDEInfo *res)
+mono_unwind_decode_llvm_mono_fde (guint8 *fde, int fde_len, guint8 *cie, guint8 *code, MonoLLVMFDEInfo *res, MonoJitExceptionInfo *ex_info, gpointer *type_info, guint8 *unw_info)
 {
 	guint8 *p, *fde_aug, *cie_cfi, *fde_cfi, *buf;
 	int has_aug, aug_len, cie_cfi_len, fde_cfi_len;
@@ -1152,7 +1160,10 @@ mono_unwind_decode_llvm_mono_fde (guint8 *fde, int fde_len, guint8 *cie, guint8
 		/* The LSDA is embedded directly into the FDE */
 		lsda = fde_aug;
 
-		decode_lsda (lsda, code, &res->ex_info, &res->ex_info_len, &res->type_info, &res->this_reg, &res->this_offset);
+		/* Get the lengths first */
+		decode_lsda (lsda, code, NULL, NULL, &res->ex_info_len, &res->this_reg, &res->this_offset);
+
+		decode_lsda (lsda, code, ex_info, type_info, NULL, &res->this_reg, &res->this_offset);
 	}
 
 	/* Decode CIE */
@@ -1183,12 +1194,13 @@ mono_unwind_decode_llvm_mono_fde (guint8 *fde, int fde_len, guint8 *cie, guint8
 	cie_cfi_len = p - cie_cfi;
 	fde_cfi_len = (fde + fde_len - fde_cfi);
 
-	buf = (guint8 *)g_malloc0 (cie_cfi_len + fde_cfi_len);
-	memcpy (buf, cie_cfi, cie_cfi_len);
-	memcpy (buf + cie_cfi_len, fde_cfi, fde_cfi_len);
+	buf = unw_info;
+	if (buf) {
+		memcpy (buf, cie_cfi, cie_cfi_len);
+		memcpy (buf + cie_cfi_len, fde_cfi, fde_cfi_len);
+	}
 
 	res->unw_info_len = cie_cfi_len + fde_cfi_len;
-	res->unw_info = buf;
 }
 
 /*