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-rw-r--r--gnu/usr.bin/gdb/gdb/parse.c827
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diff --git a/gnu/usr.bin/gdb/gdb/parse.c b/gnu/usr.bin/gdb/gdb/parse.c
new file mode 100644
index 000000000000..08f2b7e67484
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+++ b/gnu/usr.bin/gdb/gdb/parse.c
@@ -0,0 +1,827 @@
+/* Parse expressions for GDB.
+ Copyright (C) 1986, 1989, 1990, 1991 Free Software Foundation, Inc.
+ Modified from expread.y by the Department of Computer Science at the
+ State University of New York at Buffalo, 1991.
+
+This file is part of GDB.
+
+This program 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 of the License, or
+(at your option) any later version.
+
+This program 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 this program; if not, write to the Free Software
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+/* Parse an expression from text in a string,
+ and return the result as a struct expression pointer.
+ That structure contains arithmetic operations in reverse polish,
+ with constants represented by operations that are followed by special data.
+ See expression.h for the details of the format.
+ What is important here is that it can be built up sequentially
+ during the process of parsing; the lower levels of the tree always
+ come first in the result. */
+
+#include "defs.h"
+#include "symtab.h"
+#include "gdbtypes.h"
+#include "frame.h"
+#include "expression.h"
+#include "value.h"
+#include "command.h"
+#include "language.h"
+#include "parser-defs.h"
+
+static void
+free_funcalls PARAMS ((void));
+
+static void
+prefixify_expression PARAMS ((struct expression *));
+
+static int
+length_of_subexp PARAMS ((struct expression *, int));
+
+static void
+prefixify_subexp PARAMS ((struct expression *, struct expression *, int, int));
+
+/* Data structure for saving values of arglist_len for function calls whose
+ arguments contain other function calls. */
+
+struct funcall
+ {
+ struct funcall *next;
+ int arglist_len;
+ };
+
+static struct funcall *funcall_chain;
+
+/* Assign machine-independent names to certain registers
+ (unless overridden by the REGISTER_NAMES table) */
+
+#ifdef NO_STD_REGS
+unsigned num_std_regs = 0;
+struct std_regs std_regs[1];
+#else
+struct std_regs std_regs[] = {
+
+#ifdef PC_REGNUM
+ { "pc", PC_REGNUM },
+#endif
+#ifdef FP_REGNUM
+ { "fp", FP_REGNUM },
+#endif
+#ifdef SP_REGNUM
+ { "sp", SP_REGNUM },
+#endif
+#ifdef PS_REGNUM
+ { "ps", PS_REGNUM },
+#endif
+
+};
+
+unsigned num_std_regs = (sizeof std_regs / sizeof std_regs[0]);
+
+#endif
+
+
+/* Begin counting arguments for a function call,
+ saving the data about any containing call. */
+
+void
+start_arglist ()
+{
+ register struct funcall *new;
+
+ new = (struct funcall *) xmalloc (sizeof (struct funcall));
+ new->next = funcall_chain;
+ new->arglist_len = arglist_len;
+ arglist_len = 0;
+ funcall_chain = new;
+}
+
+/* Return the number of arguments in a function call just terminated,
+ and restore the data for the containing function call. */
+
+int
+end_arglist ()
+{
+ register int val = arglist_len;
+ register struct funcall *call = funcall_chain;
+ funcall_chain = call->next;
+ arglist_len = call->arglist_len;
+ free ((PTR)call);
+ return val;
+}
+
+/* Free everything in the funcall chain.
+ Used when there is an error inside parsing. */
+
+static void
+free_funcalls ()
+{
+ register struct funcall *call, *next;
+
+ for (call = funcall_chain; call; call = next)
+ {
+ next = call->next;
+ free ((PTR)call);
+ }
+}
+
+/* This page contains the functions for adding data to the struct expression
+ being constructed. */
+
+/* Add one element to the end of the expression. */
+
+/* To avoid a bug in the Sun 4 compiler, we pass things that can fit into
+ a register through here */
+
+void
+write_exp_elt (expelt)
+ union exp_element expelt;
+{
+ if (expout_ptr >= expout_size)
+ {
+ expout_size *= 2;
+ expout = (struct expression *)
+ xrealloc ((char *) expout, sizeof (struct expression)
+ + EXP_ELEM_TO_BYTES (expout_size));
+ }
+ expout->elts[expout_ptr++] = expelt;
+}
+
+void
+write_exp_elt_opcode (expelt)
+ enum exp_opcode expelt;
+{
+ union exp_element tmp;
+
+ tmp.opcode = expelt;
+
+ write_exp_elt (tmp);
+}
+
+void
+write_exp_elt_sym (expelt)
+ struct symbol *expelt;
+{
+ union exp_element tmp;
+
+ tmp.symbol = expelt;
+
+ write_exp_elt (tmp);
+}
+
+void
+write_exp_elt_block (b)
+ struct block *b;
+{
+ union exp_element tmp;
+ tmp.block = b;
+ write_exp_elt (tmp);
+}
+
+void
+write_exp_elt_longcst (expelt)
+ LONGEST expelt;
+{
+ union exp_element tmp;
+
+ tmp.longconst = expelt;
+
+ write_exp_elt (tmp);
+}
+
+void
+write_exp_elt_dblcst (expelt)
+ double expelt;
+{
+ union exp_element tmp;
+
+ tmp.doubleconst = expelt;
+
+ write_exp_elt (tmp);
+}
+
+void
+write_exp_elt_type (expelt)
+ struct type *expelt;
+{
+ union exp_element tmp;
+
+ tmp.type = expelt;
+
+ write_exp_elt (tmp);
+}
+
+void
+write_exp_elt_intern (expelt)
+ struct internalvar *expelt;
+{
+ union exp_element tmp;
+
+ tmp.internalvar = expelt;
+
+ write_exp_elt (tmp);
+}
+
+/* Add a string constant to the end of the expression.
+
+ String constants are stored by first writing an expression element
+ that contains the length of the string, then stuffing the string
+ constant itself into however many expression elements are needed
+ to hold it, and then writing another expression element that contains
+ the length of the string. I.E. an expression element at each end of
+ the string records the string length, so you can skip over the
+ expression elements containing the actual string bytes from either
+ end of the string. Note that this also allows gdb to handle
+ strings with embedded null bytes, as is required for some languages.
+
+ Don't be fooled by the fact that the string is null byte terminated,
+ this is strictly for the convenience of debugging gdb itself. Gdb
+ Gdb does not depend up the string being null terminated, since the
+ actual length is recorded in expression elements at each end of the
+ string. The null byte is taken into consideration when computing how
+ many expression elements are required to hold the string constant, of
+ course. */
+
+
+void
+write_exp_string (str)
+ struct stoken str;
+{
+ register int len = str.length;
+ register int lenelt;
+ register char *strdata;
+
+ /* Compute the number of expression elements required to hold the string
+ (including a null byte terminator), along with one expression element
+ at each end to record the actual string length (not including the
+ null byte terminator). */
+
+ lenelt = 2 + BYTES_TO_EXP_ELEM (len + 1);
+
+ /* Ensure that we have enough available expression elements to store
+ everything. */
+
+ if ((expout_ptr + lenelt) >= expout_size)
+ {
+ expout_size = max (expout_size * 2, expout_ptr + lenelt + 10);
+ expout = (struct expression *)
+ xrealloc ((char *) expout, (sizeof (struct expression)
+ + EXP_ELEM_TO_BYTES (expout_size)));
+ }
+
+ /* Write the leading length expression element (which advances the current
+ expression element index), then write the string constant followed by a
+ terminating null byte, and then write the trailing length expression
+ element. */
+
+ write_exp_elt_longcst ((LONGEST) len);
+ strdata = (char *) &expout->elts[expout_ptr];
+ memcpy (strdata, str.ptr, len);
+ *(strdata + len) = '\0';
+ expout_ptr += lenelt - 2;
+ write_exp_elt_longcst ((LONGEST) len);
+}
+
+/* Add a bitstring constant to the end of the expression.
+
+ Bitstring constants are stored by first writing an expression element
+ that contains the length of the bitstring (in bits), then stuffing the
+ bitstring constant itself into however many expression elements are
+ needed to hold it, and then writing another expression element that
+ contains the length of the bitstring. I.E. an expression element at
+ each end of the bitstring records the bitstring length, so you can skip
+ over the expression elements containing the actual bitstring bytes from
+ either end of the bitstring. */
+
+void
+write_exp_bitstring (str)
+ struct stoken str;
+{
+ register int bits = str.length; /* length in bits */
+ register int len = (bits + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT;
+ register int lenelt;
+ register char *strdata;
+
+ /* Compute the number of expression elements required to hold the bitstring,
+ along with one expression element at each end to record the actual
+ bitstring length in bits. */
+
+ lenelt = 2 + BYTES_TO_EXP_ELEM (len);
+
+ /* Ensure that we have enough available expression elements to store
+ everything. */
+
+ if ((expout_ptr + lenelt) >= expout_size)
+ {
+ expout_size = max (expout_size * 2, expout_ptr + lenelt + 10);
+ expout = (struct expression *)
+ xrealloc ((char *) expout, (sizeof (struct expression)
+ + EXP_ELEM_TO_BYTES (expout_size)));
+ }
+
+ /* Write the leading length expression element (which advances the current
+ expression element index), then write the bitstring constant, and then
+ write the trailing length expression element. */
+
+ write_exp_elt_longcst ((LONGEST) bits);
+ strdata = (char *) &expout->elts[expout_ptr];
+ memcpy (strdata, str.ptr, len);
+ expout_ptr += lenelt - 2;
+ write_exp_elt_longcst ((LONGEST) bits);
+}
+
+/* Return a null-terminated temporary copy of the name
+ of a string token. */
+
+char *
+copy_name (token)
+ struct stoken token;
+{
+ memcpy (namecopy, token.ptr, token.length);
+ namecopy[token.length] = 0;
+ return namecopy;
+}
+
+/* Reverse an expression from suffix form (in which it is constructed)
+ to prefix form (in which we can conveniently print or execute it). */
+
+static void
+prefixify_expression (expr)
+ register struct expression *expr;
+{
+ register int len =
+ sizeof (struct expression) + EXP_ELEM_TO_BYTES (expr->nelts);
+ register struct expression *temp;
+ register int inpos = expr->nelts, outpos = 0;
+
+ temp = (struct expression *) alloca (len);
+
+ /* Copy the original expression into temp. */
+ memcpy (temp, expr, len);
+
+ prefixify_subexp (temp, expr, inpos, outpos);
+}
+
+/* Return the number of exp_elements in the subexpression of EXPR
+ whose last exp_element is at index ENDPOS - 1 in EXPR. */
+
+static int
+length_of_subexp (expr, endpos)
+ register struct expression *expr;
+ register int endpos;
+{
+ register int oplen = 1;
+ register int args = 0;
+ register int i;
+
+ if (endpos < 1)
+ error ("?error in length_of_subexp");
+
+ i = (int) expr->elts[endpos - 1].opcode;
+
+ switch (i)
+ {
+ /* C++ */
+ case OP_SCOPE:
+ oplen = longest_to_int (expr->elts[endpos - 2].longconst);
+ oplen = 5 + BYTES_TO_EXP_ELEM (oplen + 1);
+ break;
+
+ case OP_LONG:
+ case OP_DOUBLE:
+ case OP_VAR_VALUE:
+ oplen = 4;
+ break;
+
+ case OP_TYPE:
+ case OP_BOOL:
+ case OP_LAST:
+ case OP_REGISTER:
+ case OP_INTERNALVAR:
+ oplen = 3;
+ break;
+
+ case OP_FUNCALL:
+ oplen = 3;
+ args = 1 + longest_to_int (expr->elts[endpos - 2].longconst);
+ break;
+
+ case UNOP_MAX:
+ case UNOP_MIN:
+ oplen = 3;
+ break;
+
+ case BINOP_VAL:
+ case UNOP_CAST:
+ case UNOP_MEMVAL:
+ oplen = 3;
+ args = 1;
+ break;
+
+ case UNOP_ABS:
+ case UNOP_CAP:
+ case UNOP_CHR:
+ case UNOP_FLOAT:
+ case UNOP_HIGH:
+ case UNOP_ODD:
+ case UNOP_ORD:
+ case UNOP_TRUNC:
+ oplen = 1;
+ args = 1;
+ break;
+
+ case STRUCTOP_STRUCT:
+ case STRUCTOP_PTR:
+ args = 1;
+ /* fall through */
+ case OP_M2_STRING:
+ case OP_STRING:
+ oplen = longest_to_int (expr->elts[endpos - 2].longconst);
+ oplen = 4 + BYTES_TO_EXP_ELEM (oplen + 1);
+ break;
+
+ case OP_BITSTRING:
+ oplen = longest_to_int (expr->elts[endpos - 2].longconst);
+ oplen = (oplen + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT;
+ oplen = 4 + BYTES_TO_EXP_ELEM (oplen);
+ break;
+
+ case OP_ARRAY:
+ oplen = 4;
+ args = longest_to_int (expr->elts[endpos - 2].longconst);
+ args -= longest_to_int (expr->elts[endpos - 3].longconst);
+ args += 1;
+ break;
+
+ case TERNOP_COND:
+ args = 3;
+ break;
+
+ /* Modula-2 */
+ case MULTI_SUBSCRIPT:
+ oplen=3;
+ args = 1 + longest_to_int (expr->elts[endpos- 2].longconst);
+ break;
+
+ case BINOP_ASSIGN_MODIFY:
+ oplen = 3;
+ args = 2;
+ break;
+
+ /* C++ */
+ case OP_THIS:
+ oplen = 2;
+ break;
+
+ default:
+ args = 1 + (i < (int) BINOP_END);
+ }
+
+ while (args > 0)
+ {
+ oplen += length_of_subexp (expr, endpos - oplen);
+ args--;
+ }
+
+ return oplen;
+}
+
+/* Copy the subexpression ending just before index INEND in INEXPR
+ into OUTEXPR, starting at index OUTBEG.
+ In the process, convert it from suffix to prefix form. */
+
+static void
+prefixify_subexp (inexpr, outexpr, inend, outbeg)
+ register struct expression *inexpr;
+ struct expression *outexpr;
+ register int inend;
+ int outbeg;
+{
+ register int oplen = 1;
+ register int args = 0;
+ register int i;
+ int *arglens;
+ enum exp_opcode opcode;
+
+ /* Compute how long the last operation is (in OPLEN),
+ and also how many preceding subexpressions serve as
+ arguments for it (in ARGS). */
+
+ opcode = inexpr->elts[inend - 1].opcode;
+ switch (opcode)
+ {
+ /* C++ */
+ case OP_SCOPE:
+ oplen = longest_to_int (inexpr->elts[inend - 2].longconst);
+ oplen = 5 + BYTES_TO_EXP_ELEM (oplen + 1);
+ break;
+
+ case OP_LONG:
+ case OP_DOUBLE:
+ case OP_VAR_VALUE:
+ oplen = 4;
+ break;
+
+ case OP_TYPE:
+ case OP_BOOL:
+ case OP_LAST:
+ case OP_REGISTER:
+ case OP_INTERNALVAR:
+ oplen = 3;
+ break;
+
+ case OP_FUNCALL:
+ oplen = 3;
+ args = 1 + longest_to_int (inexpr->elts[inend - 2].longconst);
+ break;
+
+ case UNOP_MIN:
+ case UNOP_MAX:
+ oplen = 3;
+ break;
+
+ case UNOP_CAST:
+ case UNOP_MEMVAL:
+ oplen = 3;
+ args = 1;
+ break;
+
+ case UNOP_ABS:
+ case UNOP_CAP:
+ case UNOP_CHR:
+ case UNOP_FLOAT:
+ case UNOP_HIGH:
+ case UNOP_ODD:
+ case UNOP_ORD:
+ case UNOP_TRUNC:
+ oplen=1;
+ args=1;
+ break;
+
+ case STRUCTOP_STRUCT:
+ case STRUCTOP_PTR:
+ args = 1;
+ /* fall through */
+ case OP_M2_STRING:
+ case OP_STRING:
+ oplen = longest_to_int (inexpr->elts[inend - 2].longconst);
+ oplen = 4 + BYTES_TO_EXP_ELEM (oplen + 1);
+ break;
+
+ case OP_BITSTRING:
+ oplen = longest_to_int (inexpr->elts[inend - 2].longconst);
+ oplen = (oplen + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT;
+ oplen = 4 + BYTES_TO_EXP_ELEM (oplen);
+ break;
+
+ case OP_ARRAY:
+ oplen = 4;
+ args = longest_to_int (inexpr->elts[inend - 2].longconst);
+ args -= longest_to_int (inexpr->elts[inend - 3].longconst);
+ args += 1;
+ break;
+
+ case TERNOP_COND:
+ args = 3;
+ break;
+
+ case BINOP_ASSIGN_MODIFY:
+ oplen = 3;
+ args = 2;
+ break;
+
+ /* Modula-2 */
+ case MULTI_SUBSCRIPT:
+ oplen=3;
+ args = 1 + longest_to_int (inexpr->elts[inend - 2].longconst);
+ break;
+
+ /* C++ */
+ case OP_THIS:
+ oplen = 2;
+ break;
+
+ default:
+ args = 1 + ((int) opcode < (int) BINOP_END);
+ }
+
+ /* Copy the final operator itself, from the end of the input
+ to the beginning of the output. */
+ inend -= oplen;
+ memcpy (&outexpr->elts[outbeg], &inexpr->elts[inend],
+ EXP_ELEM_TO_BYTES (oplen));
+ outbeg += oplen;
+
+ /* Find the lengths of the arg subexpressions. */
+ arglens = (int *) alloca (args * sizeof (int));
+ for (i = args - 1; i >= 0; i--)
+ {
+ oplen = length_of_subexp (inexpr, inend);
+ arglens[i] = oplen;
+ inend -= oplen;
+ }
+
+ /* Now copy each subexpression, preserving the order of
+ the subexpressions, but prefixifying each one.
+ In this loop, inend starts at the beginning of
+ the expression this level is working on
+ and marches forward over the arguments.
+ outbeg does similarly in the output. */
+ for (i = 0; i < args; i++)
+ {
+ oplen = arglens[i];
+ inend += oplen;
+ prefixify_subexp (inexpr, outexpr, inend, outbeg);
+ outbeg += oplen;
+ }
+}
+
+/* This page contains the two entry points to this file. */
+
+/* Read an expression from the string *STRINGPTR points to,
+ parse it, and return a pointer to a struct expression that we malloc.
+ Use block BLOCK as the lexical context for variable names;
+ if BLOCK is zero, use the block of the selected stack frame.
+ Meanwhile, advance *STRINGPTR to point after the expression,
+ at the first nonwhite character that is not part of the expression
+ (possibly a null character).
+
+ If COMMA is nonzero, stop if a comma is reached. */
+
+struct expression *
+parse_exp_1 (stringptr, block, comma)
+ char **stringptr;
+ struct block *block;
+ int comma;
+{
+ struct cleanup *old_chain;
+
+ lexptr = *stringptr;
+
+ paren_depth = 0;
+ type_stack_depth = 0;
+
+ comma_terminates = comma;
+
+ if (lexptr == 0 || *lexptr == 0)
+ error_no_arg ("expression to compute");
+
+ old_chain = make_cleanup (free_funcalls, 0);
+ funcall_chain = 0;
+
+ expression_context_block = block ? block : get_selected_block ();
+
+ namecopy = (char *) alloca (strlen (lexptr) + 1);
+ expout_size = 10;
+ expout_ptr = 0;
+ expout = (struct expression *)
+ xmalloc (sizeof (struct expression) + EXP_ELEM_TO_BYTES (expout_size));
+ expout->language_defn = current_language;
+ make_cleanup (free_current_contents, &expout);
+
+ if (current_language->la_parser ())
+ current_language->la_error (NULL);
+
+ discard_cleanups (old_chain);
+
+ /* Record the actual number of expression elements, and then
+ reallocate the expression memory so that we free up any
+ excess elements. */
+
+ expout->nelts = expout_ptr;
+ expout = (struct expression *)
+ xrealloc ((char *) expout,
+ sizeof (struct expression) + EXP_ELEM_TO_BYTES (expout_ptr));;
+
+ /* Convert expression from postfix form as generated by yacc
+ parser, to a prefix form. */
+
+ DUMP_EXPRESSION (expout, stdout, "before conversion to prefix form");
+ prefixify_expression (expout);
+ DUMP_EXPRESSION (expout, stdout, "after conversion to prefix form");
+
+ *stringptr = lexptr;
+ return expout;
+}
+
+/* Parse STRING as an expression, and complain if this fails
+ to use up all of the contents of STRING. */
+
+struct expression *
+parse_expression (string)
+ char *string;
+{
+ register struct expression *exp;
+ exp = parse_exp_1 (&string, 0, 0);
+ if (*string)
+ error ("Junk after end of expression.");
+ return exp;
+}
+
+/* Stuff for maintaining a stack of types. Currently just used by C, but
+ probably useful for any language which declares its types "backwards". */
+
+void
+push_type (tp)
+ enum type_pieces tp;
+{
+ if (type_stack_depth == type_stack_size)
+ {
+ type_stack_size *= 2;
+ type_stack = (union type_stack_elt *)
+ xrealloc ((char *) type_stack, type_stack_size * sizeof (*type_stack));
+ }
+ type_stack[type_stack_depth++].piece = tp;
+}
+
+void
+push_type_int (n)
+ int n;
+{
+ if (type_stack_depth == type_stack_size)
+ {
+ type_stack_size *= 2;
+ type_stack = (union type_stack_elt *)
+ xrealloc ((char *) type_stack, type_stack_size * sizeof (*type_stack));
+ }
+ type_stack[type_stack_depth++].int_val = n;
+}
+
+enum type_pieces
+pop_type ()
+{
+ if (type_stack_depth)
+ return type_stack[--type_stack_depth].piece;
+ return tp_end;
+}
+
+int
+pop_type_int ()
+{
+ if (type_stack_depth)
+ return type_stack[--type_stack_depth].int_val;
+ /* "Can't happen". */
+ return 0;
+}
+
+/* Pop the type stack and return the type which corresponds to FOLLOW_TYPE
+ as modified by all the stuff on the stack. */
+struct type *
+follow_types (follow_type)
+ struct type *follow_type;
+{
+ int done = 0;
+ int array_size;
+ struct type *range_type;
+
+ while (!done)
+ switch (pop_type ())
+ {
+ case tp_end:
+ done = 1;
+ break;
+ case tp_pointer:
+ follow_type = lookup_pointer_type (follow_type);
+ break;
+ case tp_reference:
+ follow_type = lookup_reference_type (follow_type);
+ break;
+ case tp_array:
+ array_size = pop_type_int ();
+ if (array_size != -1)
+ {
+ range_type =
+ create_range_type ((struct type *) NULL,
+ builtin_type_int, 0,
+ array_size - 1);
+ follow_type =
+ create_array_type ((struct type *) NULL,
+ follow_type, range_type);
+ }
+ else
+ follow_type = lookup_pointer_type (follow_type);
+ break;
+ case tp_function:
+ follow_type = lookup_function_type (follow_type);
+ break;
+ }
+ return follow_type;
+}
+
+void
+_initialize_parse ()
+{
+ type_stack_size = 80;
+ type_stack_depth = 0;
+ type_stack = (union type_stack_elt *)
+ xmalloc (type_stack_size * sizeof (*type_stack));
+}
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