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authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/sysdeps/generic/unwind-pe.h
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
downloadglibc-zack/build-layout-experiment.tar.gz
glibc-zack/build-layout-experiment.tar.xz
glibc-zack/build-layout-experiment.zip
Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/sysdeps/generic/unwind-pe.h')
-rw-r--r--REORG.TODO/sysdeps/generic/unwind-pe.h305
1 files changed, 305 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/generic/unwind-pe.h b/REORG.TODO/sysdeps/generic/unwind-pe.h
new file mode 100644
index 0000000000..4e2aa12074
--- /dev/null
+++ b/REORG.TODO/sysdeps/generic/unwind-pe.h
@@ -0,0 +1,305 @@
+/* Exception handling and frame unwind runtime interface routines.
+   Copyright (C) 2001-2017 Free Software Foundation, Inc.
+
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* @@@ Really this should be out of line, but this also causes link
+   compatibility problems with the base ABI.  This is slightly better
+   than duplicating code, however.  */
+
+/* If using C++, references to abort have to be qualified with std::.  */
+#ifdef __cplusplus
+#define __gxx_abort std::abort
+#else
+#define __gxx_abort abort
+#endif
+
+/* Pointer encodings, from dwarf2.h.  */
+#define DW_EH_PE_absptr         0x00
+#define DW_EH_PE_omit           0xff
+
+#define DW_EH_PE_uleb128        0x01
+#define DW_EH_PE_udata2         0x02
+#define DW_EH_PE_udata4         0x03
+#define DW_EH_PE_udata8         0x04
+#define DW_EH_PE_sleb128        0x09
+#define DW_EH_PE_sdata2         0x0A
+#define DW_EH_PE_sdata4         0x0B
+#define DW_EH_PE_sdata8         0x0C
+#define DW_EH_PE_signed         0x08
+
+#define DW_EH_PE_pcrel          0x10
+#define DW_EH_PE_textrel        0x20
+#define DW_EH_PE_datarel        0x30
+#define DW_EH_PE_funcrel        0x40
+#define DW_EH_PE_aligned        0x50
+
+#define DW_EH_PE_indirect	0x80
+
+
+#if defined(_LIBC)
+
+/* Prototypes.  */
+extern unsigned int size_of_encoded_value (unsigned char encoding)
+  attribute_hidden;
+
+extern const unsigned char *read_encoded_value_with_base
+  (unsigned char encoding, _Unwind_Ptr base,
+   const unsigned char *p, _Unwind_Ptr *val)
+  attribute_hidden;
+
+extern const unsigned char * read_encoded_value
+  (struct _Unwind_Context *context, unsigned char encoding,
+   const unsigned char *p, _Unwind_Ptr *val)
+  attribute_hidden;
+
+extern const unsigned char * read_uleb128 (const unsigned char *p,
+					   _Unwind_Word *val)
+  attribute_hidden;
+extern const unsigned char * read_sleb128 (const unsigned char *p,
+					   _Unwind_Sword *val)
+  attribute_hidden;
+
+#endif
+#if defined(_LIBC) && defined(_LIBC_DEFINITIONS)
+
+#ifdef _LIBC
+#define STATIC
+#else
+#define STATIC static
+#endif
+
+/* Given an encoding, return the number of bytes the format occupies.
+   This is only defined for fixed-size encodings, and so does not
+   include leb128.  */
+
+STATIC unsigned int
+size_of_encoded_value (unsigned char encoding)
+{
+  if (encoding == DW_EH_PE_omit)
+    return 0;
+
+  switch (encoding & 0x07)
+    {
+    case DW_EH_PE_absptr:
+      return sizeof (void *);
+    case DW_EH_PE_udata2:
+      return 2;
+    case DW_EH_PE_udata4:
+      return 4;
+    case DW_EH_PE_udata8:
+      return 8;
+    }
+  __gxx_abort ();
+}
+
+#ifndef NO_BASE_OF_ENCODED_VALUE
+
+/* Given an encoding and an _Unwind_Context, return the base to which
+   the encoding is relative.  This base may then be passed to
+   read_encoded_value_with_base for use when the _Unwind_Context is
+   not available.  */
+
+STATIC _Unwind_Ptr
+base_of_encoded_value (unsigned char encoding, struct _Unwind_Context *context)
+{
+  if (encoding == DW_EH_PE_omit)
+    return 0;
+
+  switch (encoding & 0x70)
+    {
+    case DW_EH_PE_absptr:
+    case DW_EH_PE_pcrel:
+    case DW_EH_PE_aligned:
+      return 0;
+
+    case DW_EH_PE_textrel:
+      return _Unwind_GetTextRelBase (context);
+    case DW_EH_PE_datarel:
+      return _Unwind_GetDataRelBase (context);
+    case DW_EH_PE_funcrel:
+      return _Unwind_GetRegionStart (context);
+    }
+  __gxx_abort ();
+}
+
+#endif
+
+/* Read an unsigned leb128 value from P, store the value in VAL, return
+   P incremented past the value.  We assume that a word is large enough to
+   hold any value so encoded; if it is smaller than a pointer on some target,
+   pointers should not be leb128 encoded on that target.  */
+
+STATIC const unsigned char *
+read_uleb128 (const unsigned char *p, _Unwind_Word *val)
+{
+  unsigned int shift = 0;
+  unsigned char byte;
+  _Unwind_Word result;
+
+  result = 0;
+  do
+    {
+      byte = *p++;
+      result |= (byte & 0x7f) << shift;
+      shift += 7;
+    }
+  while (byte & 0x80);
+
+  *val = result;
+  return p;
+}
+
+/* Similar, but read a signed leb128 value.  */
+
+STATIC const unsigned char *
+read_sleb128 (const unsigned char *p, _Unwind_Sword *val)
+{
+  unsigned int shift = 0;
+  unsigned char byte;
+  _Unwind_Word result;
+
+  result = 0;
+  do
+    {
+      byte = *p++;
+      result |= (byte & 0x7f) << shift;
+      shift += 7;
+    }
+  while (byte & 0x80);
+
+  /* Sign-extend a negative value.  */
+  if (shift < 8 * sizeof(result) && (byte & 0x40) != 0)
+    result |= -(1L << shift);
+
+  *val = (_Unwind_Sword) result;
+  return p;
+}
+
+/* Load an encoded value from memory at P.  The value is returned in VAL;
+   The function returns P incremented past the value.  BASE is as given
+   by base_of_encoded_value for this encoding in the appropriate context.  */
+
+STATIC const unsigned char *
+read_encoded_value_with_base (unsigned char encoding, _Unwind_Ptr base,
+			      const unsigned char *p, _Unwind_Ptr *val)
+{
+  union unaligned
+    {
+      void *ptr;
+      unsigned u2 __attribute__ ((mode (HI)));
+      unsigned u4 __attribute__ ((mode (SI)));
+      unsigned u8 __attribute__ ((mode (DI)));
+      signed s2 __attribute__ ((mode (HI)));
+      signed s4 __attribute__ ((mode (SI)));
+      signed s8 __attribute__ ((mode (DI)));
+    } __attribute__((__packed__));
+
+  union unaligned *u = (union unaligned *) p;
+  _Unwind_Internal_Ptr result;
+
+  if (encoding == DW_EH_PE_aligned)
+    {
+      _Unwind_Internal_Ptr a = (_Unwind_Internal_Ptr) p;
+      a = (a + sizeof (void *) - 1) & - sizeof(void *);
+      result = *(_Unwind_Internal_Ptr *) a;
+      p = (const unsigned char *) (a + sizeof (void *));
+    }
+  else
+    {
+      switch (encoding & 0x0f)
+	{
+	case DW_EH_PE_absptr:
+	  result = (_Unwind_Internal_Ptr) u->ptr;
+	  p += sizeof (void *);
+	  break;
+
+	case DW_EH_PE_uleb128:
+	  {
+	    _Unwind_Word tmp;
+	    p = read_uleb128 (p, &tmp);
+	    result = (_Unwind_Internal_Ptr) tmp;
+	  }
+	  break;
+
+	case DW_EH_PE_sleb128:
+	  {
+	    _Unwind_Sword tmp;
+	    p = read_sleb128 (p, &tmp);
+	    result = (_Unwind_Internal_Ptr) tmp;
+	  }
+	  break;
+
+	case DW_EH_PE_udata2:
+	  result = u->u2;
+	  p += 2;
+	  break;
+	case DW_EH_PE_udata4:
+	  result = u->u4;
+	  p += 4;
+	  break;
+	case DW_EH_PE_udata8:
+	  result = u->u8;
+	  p += 8;
+	  break;
+
+	case DW_EH_PE_sdata2:
+	  result = u->s2;
+	  p += 2;
+	  break;
+	case DW_EH_PE_sdata4:
+	  result = u->s4;
+	  p += 4;
+	  break;
+	case DW_EH_PE_sdata8:
+	  result = u->s8;
+	  p += 8;
+	  break;
+
+	default:
+	  __gxx_abort ();
+	}
+
+      if (result != 0)
+	{
+	  result += ((encoding & 0x70) == DW_EH_PE_pcrel
+		     ? (_Unwind_Internal_Ptr) u : base);
+	  if (encoding & DW_EH_PE_indirect)
+	    result = *(_Unwind_Internal_Ptr *) result;
+	}
+    }
+
+  *val = result;
+  return p;
+}
+
+#ifndef NO_BASE_OF_ENCODED_VALUE
+
+/* Like read_encoded_value_with_base, but get the base from the context
+   rather than providing it directly.  */
+
+STATIC const unsigned char *
+read_encoded_value (struct _Unwind_Context *context, unsigned char encoding,
+		    const unsigned char *p, _Unwind_Ptr *val)
+{
+  return read_encoded_value_with_base (encoding,
+		base_of_encoded_value (encoding, context),
+		p, val);
+}
+
+#endif
+#endif /* _LIBC */