Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libdw/cfi.h b/libdw/cfi.h
new file mode 100644
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+++ b/libdw/cfi.h
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+/* Internal definitions for libdw CFI interpreter.
+ Copyright (C) 2009-2010, 2013, 2015 Red Hat, Inc.
+ This file is part of elfutils.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * the GNU General Public License as published by the Free
+ Software Foundation; either version 2 of the License, or (at
+ your option) any later version
+
+ or both in parallel, as here.
+
+ elfutils 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 copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef _UNWINDP_H
+#define _UNWINDP_H 1
+
+#include "libdwP.h"
+#include "libelfP.h"
+struct ebl;
+
+/* Cached CIE representation. */
+struct dwarf_cie
+{
+ Dwarf_Off offset; /* Our position, as seen in FDEs' CIE_pointer. */
+
+ Dwarf_Word code_alignment_factor;
+ Dwarf_Sword data_alignment_factor;
+ Dwarf_Word return_address_register;
+
+ size_t fde_augmentation_data_size;
+
+ // play out to initial state
+ const uint8_t *initial_instructions;
+ const uint8_t *initial_instructions_end;
+
+ const Dwarf_Frame *initial_state;
+
+ uint8_t fde_encoding; /* DW_EH_PE_* for addresses in FDEs. */
+ uint8_t lsda_encoding; /* DW_EH_PE_* for LSDA in FDE augmentation. */
+
+ bool sized_augmentation_data; /* Saw 'z': FDEs have self-sized data. */
+ bool signal_frame; /* Saw 'S': FDE is for a signal frame. */
+};
+
+/* Cached FDE representation. */
+struct dwarf_fde
+{
+ struct dwarf_cie *cie;
+
+ /* This FDE describes PC values in [start, end). */
+ Dwarf_Addr start;
+ Dwarf_Addr end;
+
+ const uint8_t *instructions;
+ const uint8_t *instructions_end;
+};
+
+/* This holds everything we cache about the CFI from each ELF file's
+ .debug_frame or .eh_frame section. */
+struct Dwarf_CFI_s
+{
+ /* Dwarf handle we came from. If null, this is .eh_frame data. */
+ Dwarf *dbg;
+#define CFI_IS_EH(cfi) ((cfi)->dbg == NULL)
+
+ /* Data of the .debug_frame or .eh_frame section. */
+ Elf_Data_Scn *data;
+ const unsigned char *e_ident; /* For EI_DATA and EI_CLASS. */
+
+ Dwarf_Addr frame_vaddr; /* DW_EH_PE_pcrel, address of frame section. */
+ Dwarf_Addr textrel; /* DW_EH_PE_textrel base address. */
+ Dwarf_Addr datarel; /* DW_EH_PE_datarel base address. */
+
+ /* Location of next unread entry in the section. */
+ Dwarf_Off next_offset;
+
+ /* Search tree for the CIEs, indexed by CIE_pointer (section offset). */
+ void *cie_tree;
+
+ /* Search tree for the FDEs, indexed by PC address. */
+ void *fde_tree;
+
+ /* Search tree for parsed DWARF expressions, indexed by raw pointer. */
+ void *expr_tree;
+
+ /* Backend hook. */
+ struct ebl *ebl;
+
+ /* Binary search table in .eh_frame_hdr section. */
+ const uint8_t *search_table;
+ size_t search_table_len;
+ Dwarf_Addr search_table_vaddr;
+ size_t search_table_entries;
+ uint8_t search_table_encoding;
+
+ /* True if the file has a byte order different from the host. */
+ bool other_byte_order;
+
+ /* Default rule for registers not previously mentioned
+ is same_value, not undefined. */
+ bool default_same_value;
+};
+
+
+enum dwarf_frame_rule
+ {
+ reg_unspecified, /* Uninitialized state. */
+ reg_undefined, /* DW_CFA_undefined */
+ reg_same_value, /* DW_CFA_same_value */
+ reg_offset, /* DW_CFA_offset_extended et al */
+ reg_val_offset, /* DW_CFA_val_offset et al */
+ reg_register, /* DW_CFA_register */
+ reg_expression, /* DW_CFA_expression */
+ reg_val_expression, /* DW_CFA_val_expression */
+ };
+
+/* This describes what we know about an individual register. */
+struct dwarf_frame_register
+{
+ enum dwarf_frame_rule rule:3;
+
+ /* The meaning of the value bits depends on the rule:
+
+ Rule Value
+ ---- -----
+ undefined unused
+ same_value unused
+ offset(N) N (register saved at CFA + value)
+ val_offset(N) N (register = CFA + value)
+ register(R) R (register = register #value)
+ expression(E) section offset of DW_FORM_block containing E
+ (register saved at address E computes)
+ val_expression(E) section offset of DW_FORM_block containing E
+ (register = value E computes)
+ */
+ Dwarf_Sword value:(sizeof (Dwarf_Sword) * 8 - 3);
+};
+
+/* This holds instructions for unwinding frame at a particular PC location
+ described by an FDE. */
+struct Dwarf_Frame_s
+{
+ /* This frame description covers PC values in [start, end). */
+ Dwarf_Addr start;
+ Dwarf_Addr end;
+
+ Dwarf_CFI *cache;
+
+ /* Previous state saved by DW_CFA_remember_state, or .cie->initial_state,
+ or NULL in an initial_state pseudo-frame. */
+ Dwarf_Frame *prev;
+
+ /* The FDE that generated this frame state. This points to its CIE,
+ which has the return_address_register and signal_frame flag. */
+ struct dwarf_fde *fde;
+
+ /* The CFA is unknown, is R+N, or is computed by a DWARF expression.
+ A bogon in the CFI can indicate an invalid/incalculable rule.
+ We store that as cfa_invalid rather than barfing when processing it,
+ so callers can ignore the bogon unless they really need that CFA. */
+ enum { cfa_undefined, cfa_offset, cfa_expr, cfa_invalid } cfa_rule;
+ union
+ {
+ Dwarf_Op offset;
+ Dwarf_Block expr;
+ } cfa_data;
+ /* We store an offset rule as a DW_OP_bregx operation. */
+#define cfa_val_reg cfa_data.offset.number
+#define cfa_val_offset cfa_data.offset.number2
+
+ size_t nregs;
+ struct dwarf_frame_register regs[];
+};
+
+
+/* Clean up the data structure and all it points to. */
+extern void __libdw_destroy_frame_cache (Dwarf_CFI *cache)
+ __nonnull_attribute__ (1) internal_function;
+
+/* Enter a CIE encountered while reading through for FDEs. */
+extern void __libdw_intern_cie (Dwarf_CFI *cache, Dwarf_Off offset,
+ const Dwarf_CIE *info)
+ __nonnull_attribute__ (1, 3) internal_function;
+
+/* Look up a CIE_pointer for random access. */
+extern struct dwarf_cie *__libdw_find_cie (Dwarf_CFI *cache, Dwarf_Off offset)
+ __nonnull_attribute__ (1) internal_function;
+
+
+/* Look for an FDE covering the given PC address. */
+extern struct dwarf_fde *__libdw_find_fde (Dwarf_CFI *cache,
+ Dwarf_Addr address)
+ __nonnull_attribute__ (1) internal_function;
+
+/* Look for an FDE by its offset in the section. */
+extern struct dwarf_fde *__libdw_fde_by_offset (Dwarf_CFI *cache,
+ Dwarf_Off offset)
+ __nonnull_attribute__ (1) internal_function;
+
+/* Process the FDE that contains the given PC address,
+ to yield the frame state when stopped there.
+ The return value is a DWARF_E_* error code. */
+extern int __libdw_frame_at_address (Dwarf_CFI *cache, struct dwarf_fde *fde,
+ Dwarf_Addr address, Dwarf_Frame **frame)
+ __nonnull_attribute__ (1, 2, 4) internal_function;
+
+
+/* Dummy struct for memory-access.h macros. */
+#define BYTE_ORDER_DUMMY(var, e_ident) \
+ const struct { bool other_byte_order; } var = \
+ { ((BYTE_ORDER == LITTLE_ENDIAN && e_ident[EI_DATA] == ELFDATA2MSB) \
+ || (BYTE_ORDER == BIG_ENDIAN && e_ident[EI_DATA] == ELFDATA2LSB)) }
+
+
+INTDECL (dwarf_next_cfi)
+INTDECL (dwarf_getcfi)
+INTDECL (dwarf_getcfi_elf)
+INTDECL (dwarf_cfi_end)
+INTDECL (dwarf_cfi_addrframe)
+
+#endif /* unwindP.h */