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-rw-r--r--sysdeps/generic/unwind-pe.h272
1 files changed, 272 insertions, 0 deletions
diff --git a/sysdeps/generic/unwind-pe.h b/sysdeps/generic/unwind-pe.h
new file mode 100644
index 0000000000..e4a564e3e1
--- /dev/null
+++ b/sysdeps/generic/unwind-pe.h
@@ -0,0 +1,272 @@
+/* Exception handling and frame unwind runtime interface routines.
+ Copyright (C) 2001 Free Software Foundation, Inc.
+
+ This file is part of GNU CC.
+
+ GNU CC is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ GNU CC 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNU CC; see the file COPYING. If not, write to
+ the Free Software Foundation, 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+/* @@@ 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::. */
+#if __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
+
+
+/* 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. */
+
+#ifndef _LIBC
+static
+#endif
+unsigned int
+size_of_encoded_value (unsigned char encoding)
+#if defined(_LIBC) && !defined(NO_BASE_OF_ENCODED_VALUE)
+;
+#else
+{
+ 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 ();
+}
+#endif
+
+#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
+
+/* 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. */
+
+#ifndef _LIBC
+static
+#endif
+const unsigned char *
+read_encoded_value_with_base (unsigned char encoding, _Unwind_Ptr base,
+ const unsigned char *p, _Unwind_Ptr *val)
+#if defined(_LIBC) && !defined(NO_BASE_OF_ENCODED_VALUE)
+;
+#else
+{
+ 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_Ptr result;
+
+ if (encoding == DW_EH_PE_aligned)
+ {
+ _Unwind_Ptr a = (_Unwind_Ptr)p;
+ a = (a + sizeof (void *) - 1) & - sizeof(void *);
+ result = *(_Unwind_Ptr *) a;
+ p = (const unsigned char *)(a + sizeof (void *));
+ }
+ else
+ {
+ switch (encoding & 0x0f)
+ {
+ case DW_EH_PE_absptr:
+ result = (_Unwind_Ptr) u->ptr;
+ p += sizeof (void *);
+ break;
+
+ case DW_EH_PE_uleb128:
+ {
+ unsigned int shift = 0;
+ unsigned char byte;
+
+ result = 0;
+ do
+ {
+ byte = *p++;
+ result |= (_Unwind_Ptr)(byte & 0x7f) << shift;
+ shift += 7;
+ }
+ while (byte & 0x80);
+ }
+ break;
+
+ case DW_EH_PE_sleb128:
+ {
+ unsigned int shift = 0;
+ unsigned char byte;
+
+ result = 0;
+ do
+ {
+ byte = *p++;
+ result |= (_Unwind_Ptr)(byte & 0x7f) << shift;
+ shift += 7;
+ }
+ while (byte & 0x80);
+
+ if (shift < 8 * sizeof(result) && (byte & 0x40) != 0)
+ result |= -(1L << shift);
+ }
+ 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_Ptr)u : base);
+ if (encoding & DW_EH_PE_indirect)
+ result = *(_Unwind_Ptr *)result;
+ }
+ }
+
+ *val = result;
+ return p;
+}
+#endif
+
+#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 inline 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
+
+/* Read an unsigned leb128 value from P, store the value in VAL, return
+ P incremented past the value. */
+
+static inline const unsigned char *
+read_uleb128 (const unsigned char *p, _Unwind_Ptr *val)
+{
+ return read_encoded_value_with_base (DW_EH_PE_uleb128, 0, p, val);
+}
+
+/* Similar, but read a signed leb128 value. */
+
+static inline const unsigned char *
+read_sleb128 (const unsigned char *p, _Unwind_Ptr *val)
+{
+ return read_encoded_value_with_base (DW_EH_PE_sleb128, 0, p, val);
+}