X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Fdwarf2expr.h;h=2f3d2ce042d3fa5a799b2e93cc27b225c4e0f244;hb=f1f28025c3ea75d5368ddd3046461648145b89b3;hp=6b5d64988aac6546018059a1157aa650efbceefc;hpb=b64f50a1aee2274fa2ec530a8ad191ae0f27706c;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/dwarf2expr.h b/gdb/dwarf2expr.h index 6b5d64988a..2f3d2ce042 100644 --- a/gdb/dwarf2expr.h +++ b/gdb/dwarf2expr.h @@ -1,7 +1,6 @@ /* DWARF 2 Expression Evaluator. - Copyright (C) 2001-2003, 2005, 2007-2012 Free Software Foundation, - Inc. + Copyright (C) 2001-2020 Free Software Foundation, Inc. Contributed by Daniel Berlin . @@ -23,75 +22,8 @@ #if !defined (DWARF2EXPR_H) #define DWARF2EXPR_H -struct dwarf_expr_context; - -/* Offset relative to the start of its containing CU (compilation unit). */ -typedef struct -{ - unsigned int cu_off; -} cu_offset; - -/* Offset relative to the start of its .debug_info or .debug_types section. */ -typedef struct -{ - unsigned int sect_off; -} sect_offset; - -/* Virtual method table for struct dwarf_expr_context below. */ - -struct dwarf_expr_context_funcs -{ - /* Return the value of register number REGNUM. */ - CORE_ADDR (*read_reg) (void *baton, int regnum); - - /* Read LENGTH bytes at ADDR into BUF. */ - void (*read_mem) (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t length); - - /* Return the location expression for the frame base attribute, in - START and LENGTH. The result must be live until the current - expression evaluation is complete. */ - void (*get_frame_base) (void *baton, const gdb_byte **start, size_t *length); - - /* Return the CFA for the frame. */ - CORE_ADDR (*get_frame_cfa) (void *baton); - - /* Return the PC for the frame. */ - CORE_ADDR (*get_frame_pc) (void *baton); - - /* Return the thread-local storage address for - DW_OP_GNU_push_tls_address. */ - CORE_ADDR (*get_tls_address) (void *baton, CORE_ADDR offset); - - /* Execute DW_AT_location expression for the DWARF expression subroutine in - the DIE at DIE_OFFSET in the CU from CTX. Do not touch STACK while it - being passed to and returned from the called DWARF subroutine. */ - void (*dwarf_call) (struct dwarf_expr_context *ctx, cu_offset die_offset); - - /* Return the base type given by the indicated DIE. This can throw - an exception if the DIE is invalid or does not represent a base - type. If can also be NULL in the special case where the - callbacks are not performing evaluation, and thus it is - meaningful to substitute a stub type of the correct size. */ - struct type *(*get_base_type) (struct dwarf_expr_context *ctx, cu_offset die); - - /* Push on DWARF stack an entry evaluated for DW_TAG_GNU_call_site's - DWARF_REG/FB_OFFSET at the caller of specified BATON. If DWARF register - number DWARF_REG specifying the push_dwarf_reg_entry_value parameter is - not -1 FB_OFFSET is ignored. Otherwise FB_OFFSET specifies stack - parameter offset against caller's stack pointer (which equals the callee's - frame base). If DEREF_SIZE is not -1 then use - DW_AT_GNU_call_site_data_value instead of DW_AT_GNU_call_site_value. */ - void (*push_dwarf_reg_entry_value) (struct dwarf_expr_context *ctx, - int dwarf_reg, CORE_ADDR fb_offset, - int deref_size); - -#if 0 - /* Not yet implemented. */ - - /* Return the `object address' for DW_OP_push_object_address. */ - CORE_ADDR (*get_object_address) (void *baton); -#endif -}; +#include "leb128.h" +#include "gdbtypes.h" /* The location of a value. */ enum dwarf_value_location @@ -117,30 +49,85 @@ enum dwarf_value_location DWARF_VALUE_IMPLICIT_POINTER }; +/* A piece of an object, as recorded by DW_OP_piece or DW_OP_bit_piece. */ +struct dwarf_expr_piece +{ + enum dwarf_value_location location; + + union + { + struct + { + /* This piece's address, for DWARF_VALUE_MEMORY pieces. */ + CORE_ADDR addr; + /* Non-zero if the piece is known to be in memory and on + the program's stack. */ + bool in_stack_memory; + } mem; + + /* The piece's register number, for DWARF_VALUE_REGISTER pieces. */ + int regno; + + /* The piece's literal value, for DWARF_VALUE_STACK pieces. */ + struct value *value; + + struct + { + /* A pointer to the data making up this piece, + for DWARF_VALUE_LITERAL pieces. */ + const gdb_byte *data; + /* The length of the available data. */ + ULONGEST length; + } literal; + + /* Used for DWARF_VALUE_IMPLICIT_POINTER. */ + struct + { + /* The referent DIE from DW_OP_implicit_pointer. */ + sect_offset die_sect_off; + /* The byte offset into the resulting data. */ + LONGEST offset; + } ptr; + } v; + + /* The length of the piece, in bits. */ + ULONGEST size; + /* The piece offset, in bits. */ + ULONGEST offset; +}; + /* The dwarf expression stack. */ struct dwarf_stack_value { + dwarf_stack_value (struct value *value_, int in_stack_memory_) + : value (value_), in_stack_memory (in_stack_memory_) + {} + struct value *value; - /* Non-zero if the piece is in memory and is known to be - on the program's stack. It is always ok to set this to zero. - This is used, for example, to optimize memory access from the target. - It can vastly speed up backtraces on long latency connections when - "set stack-cache on". */ - int in_stack_memory; + /* True if the piece is in memory and is known to be on the program's stack. + It is always ok to set this to zero. This is used, for example, to + optimize memory access from the target. It can vastly speed up backtraces + on long latency connections when "set stack-cache on". */ + bool in_stack_memory; }; /* The expression evaluator works with a dwarf_expr_context, describing its current state and its callbacks. */ struct dwarf_expr_context { - /* The stack of values, allocated with xmalloc. */ - struct dwarf_stack_value *stack; + dwarf_expr_context (); + virtual ~dwarf_expr_context () = default; + + void push_address (CORE_ADDR value, bool in_stack_memory); + void eval (const gdb_byte *addr, size_t len); + struct value *fetch (int n); + CORE_ADDR fetch_address (int n); + bool fetch_in_stack_memory (int n); - /* The number of values currently pushed on the stack, and the - number of elements allocated to the stack. */ - int stack_len, stack_allocated; + /* The stack of values. */ + std::vector stack; /* Target architecture to use for address operations. */ struct gdbarch *gdbarch; @@ -152,16 +139,10 @@ struct dwarf_expr_context context and operations depending on DW_FORM_ref_addr are not allowed. */ int ref_addr_size; - /* Offset used to relocate DW_OP_addr argument. */ + /* Offset used to relocate DW_OP_addr, DW_OP_addrx, and + DW_OP_GNU_addr_index arguments. */ CORE_ADDR offset; - /* An opaque argument provided by the caller, which will be passed - to all of the callback functions. */ - void *baton; - - /* Callback functions. */ - const struct dwarf_expr_context_funcs *funcs; - /* The current depth of dwarf expression recursion, via DW_OP_call*, DW_OP_fbreg, DW_OP_push_object_address, etc., and the maximum depth we'll tolerate before raising an error. */ @@ -172,7 +153,7 @@ struct dwarf_expr_context /* For DWARF_VALUE_LITERAL, the current literal value's length and data. For DWARF_VALUE_IMPLICIT_POINTER, LEN is the offset of the - target DIE of cu_offset kind. */ + target DIE of sect_offset kind. */ ULONGEST len; const gdb_byte *data; @@ -180,8 +161,7 @@ struct dwarf_expr_context initialized; zero otherwise. */ int initialized; - /* An array of pieces. PIECES points to its first element; - NUM_PIECES is its length. + /* A vector of pieces. Each time DW_OP_piece is executed, we add a new element to the end of this array, recording the current top of the stack, the @@ -203,97 +183,86 @@ struct dwarf_expr_context no DW_OP_piece operations have no value to place in a piece's 'size' field; the size comes from the surrounding data. So the two cases need to be handled separately.) */ - int num_pieces; - struct dwarf_expr_piece *pieces; -}; - - -/* A piece of an object, as recorded by DW_OP_piece or DW_OP_bit_piece. */ -struct dwarf_expr_piece -{ - enum dwarf_value_location location; + std::vector pieces; - union - { - struct - { - /* This piece's address, for DWARF_VALUE_MEMORY pieces. */ - CORE_ADDR addr; - /* Non-zero if the piece is known to be in memory and on - the program's stack. */ - int in_stack_memory; - } mem; + /* Return the value of register number REGNUM (a DWARF register number), + read as an address. */ + virtual CORE_ADDR read_addr_from_reg (int regnum) = 0; - /* The piece's register number, for DWARF_VALUE_REGISTER pieces. */ - int regno; + /* Return a value of type TYPE, stored in register number REGNUM + of the frame associated to the given BATON. - /* The piece's literal value, for DWARF_VALUE_STACK pieces. */ - struct value *value; + REGNUM is a DWARF register number. */ + virtual struct value *get_reg_value (struct type *type, int regnum) = 0; - struct - { - /* A pointer to the data making up this piece, - for DWARF_VALUE_LITERAL pieces. */ - const gdb_byte *data; - /* The length of the available data. */ - ULONGEST length; - } literal; + /* Read LENGTH bytes at ADDR into BUF. */ + virtual void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t length) = 0; - /* Used for DWARF_VALUE_IMPLICIT_POINTER. */ - struct - { - /* The referent DIE from DW_OP_GNU_implicit_pointer. */ - cu_offset die; - /* The byte offset into the resulting data. */ - LONGEST offset; - } ptr; - } v; + /* Return the location expression for the frame base attribute, in + START and LENGTH. The result must be live until the current + expression evaluation is complete. */ + virtual void get_frame_base (const gdb_byte **start, size_t *length) = 0; - /* The length of the piece, in bits. */ - ULONGEST size; - /* The piece offset, in bits. */ - ULONGEST offset; -}; + /* Return the CFA for the frame. */ + virtual CORE_ADDR get_frame_cfa () = 0; -struct dwarf_expr_context *new_dwarf_expr_context (void); -void free_dwarf_expr_context (struct dwarf_expr_context *ctx); -struct cleanup * - make_cleanup_free_dwarf_expr_context (struct dwarf_expr_context *ctx); + /* Return the PC for the frame. */ + virtual CORE_ADDR get_frame_pc () + { + error (_("%s is invalid in this context"), "DW_OP_implicit_pointer"); + } -void dwarf_expr_push_address (struct dwarf_expr_context *ctx, - CORE_ADDR value, - int in_stack_memory); -void dwarf_expr_eval (struct dwarf_expr_context *ctx, const gdb_byte *addr, - size_t len); -struct value *dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n); -CORE_ADDR dwarf_expr_fetch_address (struct dwarf_expr_context *ctx, int n); -int dwarf_expr_fetch_in_stack_memory (struct dwarf_expr_context *ctx, int n); + /* Return the thread-local storage address for + DW_OP_GNU_push_tls_address or DW_OP_form_tls_address. */ + virtual CORE_ADDR get_tls_address (CORE_ADDR offset) = 0; + + /* Execute DW_AT_location expression for the DWARF expression + subroutine in the DIE at DIE_CU_OFF in the CU. Do not touch + STACK while it being passed to and returned from the called DWARF + subroutine. */ + virtual void dwarf_call (cu_offset die_cu_off) = 0; + + /* Execute "variable value" operation on the DIE at SECT_OFF. */ + virtual struct value *dwarf_variable_value (sect_offset sect_off) = 0; + + /* Return the base type given by the indicated DIE at DIE_CU_OFF. + This can throw an exception if the DIE is invalid or does not + represent a base type. SIZE is non-zero if this function should + verify that the resulting type has the correct size. */ + virtual struct type *get_base_type (cu_offset die_cu_off, int size) + { + /* Anything will do. */ + return builtin_type (this->gdbarch)->builtin_int; + } + + /* Push on DWARF stack an entry evaluated for DW_TAG_call_site's + parameter matching KIND and KIND_U at the caller of specified BATON. + If DEREF_SIZE is not -1 then use DW_AT_call_data_value instead of + DW_AT_call_value. */ + virtual void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind, + union call_site_parameter_u kind_u, + int deref_size) = 0; + + /* Return the address indexed by DW_OP_addrx or DW_OP_GNU_addr_index. + This can throw an exception if the index is out of range. */ + virtual CORE_ADDR get_addr_index (unsigned int index) = 0; + /* Return the `object address' for DW_OP_push_object_address. */ + virtual CORE_ADDR get_object_address () = 0; -const gdb_byte *read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end, - ULONGEST * r); -const gdb_byte *read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end, - LONGEST * r); +private: -const char *dwarf_stack_op_name (unsigned int); + struct type *address_type () const; + void push (struct value *value, bool in_stack_memory); + bool stack_empty_p () const; + void add_piece (ULONGEST size, ULONGEST offset); + void execute_stack_op (const gdb_byte *op_ptr, const gdb_byte *op_end); + void pop (); +}; void dwarf_expr_require_composition (const gdb_byte *, const gdb_byte *, const char *); -/* Stub dwarf_expr_context_funcs implementations. */ - -void ctx_no_get_frame_base (void *baton, const gdb_byte **start, - size_t *length); -CORE_ADDR ctx_no_get_frame_cfa (void *baton); -CORE_ADDR ctx_no_get_frame_pc (void *baton); -CORE_ADDR ctx_no_get_tls_address (void *baton, CORE_ADDR offset); -void ctx_no_dwarf_call (struct dwarf_expr_context *ctx, cu_offset die_offset); -struct type *ctx_no_get_base_type (struct dwarf_expr_context *ctx, - cu_offset die); -void ctx_no_push_dwarf_reg_entry_value (struct dwarf_expr_context *ctx, - int dwarf_reg, CORE_ADDR fb_offset, - int deref_size); - int dwarf_block_to_dwarf_reg (const gdb_byte *buf, const gdb_byte *buf_end); int dwarf_block_to_dwarf_reg_deref (const gdb_byte *buf, @@ -307,4 +276,50 @@ int dwarf_block_to_sp_offset (struct gdbarch *gdbarch, const gdb_byte *buf, const gdb_byte *buf_end, CORE_ADDR *sp_offset_return); +/* Wrappers around the leb128 reader routines to simplify them for our + purposes. */ + +static inline const gdb_byte * +gdb_read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end, + uint64_t *r) +{ + size_t bytes_read = read_uleb128_to_uint64 (buf, buf_end, r); + + if (bytes_read == 0) + return NULL; + return buf + bytes_read; +} + +static inline const gdb_byte * +gdb_read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end, + int64_t *r) +{ + size_t bytes_read = read_sleb128_to_int64 (buf, buf_end, r); + + if (bytes_read == 0) + return NULL; + return buf + bytes_read; +} + +static inline const gdb_byte * +gdb_skip_leb128 (const gdb_byte *buf, const gdb_byte *buf_end) +{ + size_t bytes_read = skip_leb128 (buf, buf_end); + + if (bytes_read == 0) + return NULL; + return buf + bytes_read; +} + +extern const gdb_byte *safe_read_uleb128 (const gdb_byte *buf, + const gdb_byte *buf_end, + uint64_t *r); + +extern const gdb_byte *safe_read_sleb128 (const gdb_byte *buf, + const gdb_byte *buf_end, + int64_t *r); + +extern const gdb_byte *safe_skip_leb128 (const gdb_byte *buf, + const gdb_byte *buf_end); + #endif /* dwarf2expr.h */