Differential D2534 Diff 5438 head/contrib/gdb/gdb/dwarf2expr.h

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head/contrib/gdb/gdb/dwarf2expr.h

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/* The current depth of dwarf expression recursion, via DW_OP_call*,		/* The current depth of dwarf expression recursion, via DW_OP_call*,
DW_OP_fbreg, DW_OP_push_object_address, etc., and the maximum		DW_OP_fbreg, DW_OP_push_object_address, etc., and the maximum
depth we'll tolerate before raising an error. */		depth we'll tolerate before raising an error. */
int recursion_depth, max_recursion_depth;		int recursion_depth, max_recursion_depth;

/* Non-zero if the result is in a register. The register number		/* Non-zero if the result is in a register. The register number
will be on the expression stack. */		will be on the expression stack. */
int in_reg;		int in_reg;
		/* Initialization status of variable: Non-zero if variable has been
		initialized; zero otherwise. */
		int initialized;

		/* An array of pieces. PIECES points to its first element;
		NUM_PIECES is its length.

		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
		current in_reg flag, and the size given as the operand to
		DW_OP_piece. We then pop the top value from the stack, clear the
		in_reg flag, and resume evaluation.

		The Dwarf spec doesn't say whether DW_OP_piece pops the top value
		from the stack. We do, ensuring that clients of this interface
		expecting to see a value left on the top of the stack (say, code
		evaluating frame base expressions or CFA's specified with
		DW_CFA_def_cfa_expression) will get an error if the expression
		actually marks all the values it computes as pieces.

		If an expression never uses DW_OP_piece, num_pieces will be zero.
		(It would be nice to present these cases as expressions yielding
		a single piece, with in_reg clear, so that callers need not
		distinguish between the no-DW_OP_piece and one-DW_OP_piece cases.
		But expressions with 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
		{
		/* If IN_REG is zero, then the piece is in memory, and VALUE is its address.
		If IN_REG is non-zero, then the piece is in a register, and VALUE
		is the register number. */
		int in_reg;

		/* This piece's address or register number. */
		CORE_ADDR value;

		/* The length of the piece, in bytes. */
		ULONGEST size;
};		};

struct dwarf_expr_context *new_dwarf_expr_context (void);		struct dwarf_expr_context *new_dwarf_expr_context (void);
void free_dwarf_expr_context (struct dwarf_expr_context *ctx);		void free_dwarf_expr_context (struct dwarf_expr_context *ctx);

void dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value);		void dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value);
void dwarf_expr_pop (struct dwarf_expr_context *ctx);		void dwarf_expr_pop (struct dwarf_expr_context *ctx);
void dwarf_expr_eval (struct dwarf_expr_context ctx, unsigned char addr,		void dwarf_expr_eval (struct dwarf_expr_context ctx, unsigned char addr,
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