/* Frame unwinder for frames with DWARF Call Frame Information.
- Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010
- Free Software Foundation, Inc.
+ Copyright (C) 2003-2020 Free Software Foundation, Inc.
Contributed by Mark Kettenis.
struct gdbarch;
struct objfile;
struct frame_info;
+struct dwarf2_per_cu_data;
+struct agent_expr;
+struct axs_value;
/* Register rule. */
DWARF2_FRAME_REG_UNSPECIFIED = 0,
/* The term "undefined" comes from the DWARF2 CFI spec which this
- code is moddeling; it indicates that the register's value is
+ code is modeling; it indicates that the register's value is
"undefined". GCC uses the less formal term "unsaved". Its
definition is a combination of REG_UNDEFINED and REG_UNSPECIFIED.
The failure to differentiate the two helps explain a few problems
union {
LONGEST offset;
ULONGEST reg;
- unsigned char *exp;
+ struct
+ {
+ const gdb_byte *start;
+ ULONGEST len;
+ } exp;
struct value *(*fn) (struct frame_info *this_frame, void **this_cache,
int regnum);
} loc;
- ULONGEST exp_len;
enum dwarf2_frame_reg_rule how;
};
+enum cfa_how_kind
+{
+ CFA_UNSET,
+ CFA_REG_OFFSET,
+ CFA_EXP
+};
+
+struct dwarf2_frame_state_reg_info
+{
+ dwarf2_frame_state_reg_info () = default;
+ ~dwarf2_frame_state_reg_info ()
+ {
+ delete prev;
+ }
+
+ /* Copy constructor. */
+ dwarf2_frame_state_reg_info (const dwarf2_frame_state_reg_info &src)
+ : reg (src.reg), cfa_offset (src.cfa_offset),
+ cfa_reg (src.cfa_reg), cfa_how (src.cfa_how), cfa_exp (src.cfa_exp),
+ prev (src.prev)
+ {
+ }
+
+ /* Assignment operator for both move-assignment and copy-assignment. */
+ dwarf2_frame_state_reg_info&
+ operator= (dwarf2_frame_state_reg_info rhs)
+ {
+ swap (*this, rhs);
+ return *this;
+ }
+
+ /* Move constructor. */
+ dwarf2_frame_state_reg_info (dwarf2_frame_state_reg_info &&rhs) noexcept
+ : reg (std::move (rhs.reg)), cfa_offset (rhs.cfa_offset),
+ cfa_reg (rhs.cfa_reg), cfa_how (rhs.cfa_how), cfa_exp (rhs.cfa_exp),
+ prev (rhs.prev)
+ {
+ rhs.prev = nullptr;
+ }
+
+ /* If necessary, enlarge the register set to hold NUM_REGS_REQUESTED
+ registers. */
+ void alloc_regs (int num_regs_requested)
+ {
+ gdb_assert (num_regs_requested > 0);
+
+ if (num_regs_requested <= reg.size ())
+ return;
+
+ reg.resize (num_regs_requested);
+ }
+
+ std::vector<struct dwarf2_frame_state_reg> reg;
+
+ LONGEST cfa_offset = 0;
+ ULONGEST cfa_reg = 0;
+ enum cfa_how_kind cfa_how = CFA_UNSET;
+ const gdb_byte *cfa_exp = NULL;
+
+ /* Used to implement DW_CFA_remember_state. */
+ struct dwarf2_frame_state_reg_info *prev = NULL;
+
+private:
+ friend void swap (dwarf2_frame_state_reg_info& lhs,
+ dwarf2_frame_state_reg_info& rhs)
+ {
+ using std::swap;
+
+ swap (lhs.reg, rhs.reg);
+ swap (lhs.cfa_offset, rhs.cfa_offset);
+ swap (lhs.cfa_reg, rhs.cfa_reg);
+ swap (lhs.cfa_how, rhs.cfa_how);
+ swap (lhs.cfa_exp, rhs.cfa_exp);
+ swap (lhs.prev, rhs.prev);
+ }
+};
+
+struct dwarf2_cie;
+
+/* Structure describing a frame state. */
+
+struct dwarf2_frame_state
+{
+ dwarf2_frame_state (CORE_ADDR pc, struct dwarf2_cie *cie);
+
+ /* Each register save state can be described in terms of a CFA slot,
+ another register, or a location expression. */
+ struct dwarf2_frame_state_reg_info regs {};
+
+ /* The PC described by the current frame state. */
+ CORE_ADDR pc;
+
+ /* Initial register set from the CIE.
+ Used to implement DW_CFA_restore. */
+ struct dwarf2_frame_state_reg_info initial {};
+
+ /* The information we care about from the CIE. */
+ const LONGEST data_align;
+ const ULONGEST code_align;
+ const ULONGEST retaddr_column;
+
+ /* Flags for known producer quirks. */
+
+ /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa
+ and DW_CFA_def_cfa_offset takes a factored offset. */
+ bool armcc_cfa_offsets_sf = false;
+
+ /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that
+ the CFA is defined as REG - OFFSET rather than REG + OFFSET. */
+ bool armcc_cfa_offsets_reversed = false;
+};
+
+/* When this is true the DWARF frame unwinders can be used if they are
+ registered with the gdbarch. Not all architectures can or do use the
+ DWARF unwinders. Setting this to true on a target that does not
+ otherwise support the DWARF unwinders has no effect. */
+extern bool dwarf2_frame_unwinders_enabled_p;
+
/* Set the architecture-specific register state initialization
function for GDBARCH to INIT_REG. */
extern const struct frame_base *
dwarf2_frame_base_sniffer (struct frame_info *this_frame);
-/* Register the DWARF CFI for OBJFILE. */
-
-void dwarf2_frame_build_info (struct objfile *objfile);
-
/* Compute the DWARF CFA for a frame. */
CORE_ADDR dwarf2_frame_cfa (struct frame_info *this_frame);
+/* Find the CFA information for PC.
+
+ Return 1 if a register is used for the CFA, or 0 if another
+ expression is used. Throw an exception on error.
+
+ GDBARCH is the architecture to use.
+ DATA is the per-CU data.
+
+ REGNUM_OUT is an out parameter that is set to the register number.
+ OFFSET_OUT is the offset to use from this register.
+ These are only filled in when 1 is returned.
+
+ TEXT_OFFSET_OUT, CFA_START_OUT, and CFA_END_OUT describe the CFA
+ in other cases. These are only used when 0 is returned. */
+
+extern int dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc,
+ struct dwarf2_per_cu_data *data,
+ int *regnum_out, LONGEST *offset_out,
+ CORE_ADDR *text_offset_out,
+ const gdb_byte **cfa_start_out,
+ const gdb_byte **cfa_end_out);
+
#endif /* dwarf2-frame.h */
projects / deliverable / binutils-gdb.git / blobdiff