+/* Print in infix form a struct expression.
+ Copyright (C) 1986, 1989 Free Software Foundation, Inc.
+
+This file is part of GDB.
+
+GDB 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 1, or (at your option)
+any later version.
+
+GDB 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 GDB; see the file COPYING. If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include <stdio.h>
+#include "defs.h"
+#include "symtab.h"
+#include "param.h"
+#include "expression.h"
+#include "value.h"
+
+\f
+/* These codes indicate operator precedences, least tightly binding first. */
+/* Adding 1 to a precedence value is done for binary operators,
+ on the operand which is more tightly bound, so that operators
+ of equal precedence within that operand will get parentheses. */
+/* PREC_HYPER and PREC_ABOVE_COMMA are not the precedence of any operator;
+ they are used as the "surrounding precedence" to force
+ various kinds of things to be parenthesized. */
+enum precedence
+{ PREC_NULL, PREC_COMMA, PREC_ABOVE_COMMA, PREC_ASSIGN, PREC_OR, PREC_AND,
+ PREC_LOGIOR, PREC_LOGAND, PREC_LOGXOR, PREC_EQUAL, PREC_ORDER,
+ PREC_SHIFT, PREC_ADD, PREC_MUL, PREC_REPEAT,
+ PREC_HYPER, PREC_PREFIX, PREC_SUFFIX };
+
+/* Table mapping opcodes into strings for printing operators
+ and precedences of the operators. */
+
+struct op_print
+{
+ char *string;
+ enum exp_opcode opcode;
+ /* Precedence of operator. These values are used only by comparisons. */
+ enum precedence precedence;
+ int right_assoc;
+};
+
+static struct op_print op_print_tab[] =
+ {
+ {",", BINOP_COMMA, PREC_COMMA, 0},
+ {"=", BINOP_ASSIGN, PREC_ASSIGN, 1},
+ {"||", BINOP_OR, PREC_OR, 0},
+ {"&&", BINOP_AND, PREC_AND, 0},
+ {"|", BINOP_LOGIOR, PREC_LOGIOR, 0},
+ {"&", BINOP_LOGAND, PREC_LOGAND, 0},
+ {"^", BINOP_LOGXOR, PREC_LOGXOR, 0},
+ {"==", BINOP_EQUAL, PREC_EQUAL, 0},
+ {"!=", BINOP_NOTEQUAL, PREC_EQUAL, 0},
+ {"<=", BINOP_LEQ, PREC_ORDER, 0},
+ {">=", BINOP_GEQ, PREC_ORDER, 0},
+ {">", BINOP_GTR, PREC_ORDER, 0},
+ {"<", BINOP_LESS, PREC_ORDER, 0},
+ {">>", BINOP_RSH, PREC_SHIFT, 0},
+ {"<<", BINOP_LSH, PREC_SHIFT, 0},
+ {"+", BINOP_ADD, PREC_ADD, 0},
+ {"-", BINOP_SUB, PREC_ADD, 0},
+ {"*", BINOP_MUL, PREC_MUL, 0},
+ {"/", BINOP_DIV, PREC_MUL, 0},
+ {"%", BINOP_REM, PREC_MUL, 0},
+ {"@", BINOP_REPEAT, PREC_REPEAT, 0},
+ {"-", UNOP_NEG, PREC_PREFIX, 0},
+ {"!", UNOP_ZEROP, PREC_PREFIX, 0},
+ {"~", UNOP_LOGNOT, PREC_PREFIX, 0},
+ {"*", UNOP_IND, PREC_PREFIX, 0},
+ {"&", UNOP_ADDR, PREC_PREFIX, 0},
+ {"sizeof ", UNOP_SIZEOF, PREC_PREFIX, 0},
+ {"++", UNOP_PREINCREMENT, PREC_PREFIX, 0},
+ {"--", UNOP_PREDECREMENT, PREC_PREFIX, 0},
+ /* C++ */
+ {"::", BINOP_SCOPE, PREC_PREFIX, 0},
+ };
+\f
+static void print_subexp ();
+
+void
+print_expression (exp, stream)
+ struct expression *exp;
+ FILE *stream;
+{
+ int pc = 0;
+ print_subexp (exp, &pc, stream, PREC_NULL);
+}
+
+/* Print the subexpression of EXP that starts in position POS, on STREAM.
+ PREC is the precedence of the surrounding operator;
+ if the precedence of the main operator of this subexpression is less,
+ parentheses are needed here. */
+
+static void
+print_subexp (exp, pos, stream, prec)
+ register struct expression *exp;
+ register int *pos;
+ FILE *stream;
+ enum precedence prec;
+{
+ register int tem;
+ register int pc;
+ int nargs;
+ register char *op_str;
+ int assign_modify = 0;
+ enum exp_opcode opcode;
+ enum precedence myprec;
+ /* Set to 1 for a right-associative operator. */
+ int assoc;
+
+ pc = (*pos)++;
+ opcode = exp->elts[pc].opcode;
+ switch (opcode)
+ {
+ case OP_SCOPE:
+ myprec = PREC_PREFIX;
+ assoc = 0;
+ (*pos) += 2;
+ print_subexp (exp, pos, stream, (int) myprec + assoc);
+ fprintf (stream, " :: ");
+ nargs = strlen (&exp->elts[pc + 2].string);
+ (*pos) += 1 + (nargs + sizeof (union exp_element)) / sizeof (union exp_element);
+
+ fprintf (stream, &exp->elts[pc + 2].string);
+ return;
+
+ case OP_LONG:
+ (*pos) += 3;
+ value_print (value_from_long (exp->elts[pc + 1].type,
+ exp->elts[pc + 2].longconst),
+ stream, 0, Val_no_prettyprint);
+ return;
+
+ case OP_DOUBLE:
+ (*pos) += 3;
+ value_print (value_from_double (exp->elts[pc + 1].type,
+ exp->elts[pc + 2].doubleconst),
+ stream, 0, Val_no_prettyprint);
+ return;
+
+ case OP_VAR_VALUE:
+ (*pos) += 2;
+ fprintf (stream, "%s", SYMBOL_NAME (exp->elts[pc + 1].symbol));
+ return;
+
+ case OP_LAST:
+ (*pos) += 2;
+ fprintf (stream, "$%d", (int) exp->elts[pc + 1].longconst);
+ return;
+
+ case OP_REGISTER:
+ (*pos) += 2;
+ fprintf (stream, "$%s", reg_names[exp->elts[pc + 1].longconst]);
+ return;
+
+ case OP_INTERNALVAR:
+ (*pos) += 2;
+ fprintf (stream, "$%s",
+ internalvar_name (exp->elts[pc + 1].internalvar));
+ return;
+
+ case OP_FUNCALL:
+ (*pos) += 2;
+ nargs = exp->elts[pc + 1].longconst;
+ print_subexp (exp, pos, stream, PREC_SUFFIX);
+ fprintf (stream, " (");
+ for (tem = 0; tem < nargs; tem++)
+ {
+ if (tem > 0)
+ fprintf (stream, ", ");
+ print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
+ }
+ fprintf (stream, ")");
+ return;
+
+ case OP_STRING:
+ nargs = strlen (&exp->elts[pc + 1].string);
+ (*pos) += 2 + (nargs + sizeof (union exp_element)) / sizeof (union exp_element);
+ fprintf (stream, "\"");
+ for (tem = 0; tem < nargs; tem++)
+ printchar ((&exp->elts[pc + 1].string)[tem], stream, '"');
+ fprintf (stream, "\"");
+ return;
+
+ case TERNOP_COND:
+ if ((int) prec > (int) PREC_COMMA)
+ fprintf (stream, "(");
+ /* Print the subexpressions, forcing parentheses
+ around any binary operations within them.
+ This is more parentheses than are strictly necessary,
+ but it looks clearer. */
+ print_subexp (exp, pos, stream, PREC_HYPER);
+ fprintf (stream, " ? ");
+ print_subexp (exp, pos, stream, PREC_HYPER);
+ fprintf (stream, " : ");
+ print_subexp (exp, pos, stream, PREC_HYPER);
+ if ((int) prec > (int) PREC_COMMA)
+ fprintf (stream, ")");
+ return;
+
+ case STRUCTOP_STRUCT:
+ tem = strlen (&exp->elts[pc + 1].string);
+ (*pos) += 2 + (tem + sizeof (union exp_element)) / sizeof (union exp_element);
+ print_subexp (exp, pos, stream, PREC_SUFFIX);
+ fprintf (stream, ".%s", &exp->elts[pc + 1].string);
+ return;
+
+ case STRUCTOP_PTR:
+ tem = strlen (&exp->elts[pc + 1].string);
+ (*pos) += 2 + (tem + sizeof (union exp_element)) / sizeof (union exp_element);
+ print_subexp (exp, pos, stream, PREC_SUFFIX);
+ fprintf (stream, "->%s", &exp->elts[pc + 1].string);
+ return;
+
+ case BINOP_SUBSCRIPT:
+ print_subexp (exp, pos, stream, PREC_SUFFIX);
+ fprintf (stream, "[");
+ print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
+ fprintf (stream, "]");
+ return;
+
+ case UNOP_POSTINCREMENT:
+ print_subexp (exp, pos, stream, PREC_SUFFIX);
+ fprintf (stream, "++");
+ return;
+
+ case UNOP_POSTDECREMENT:
+ print_subexp (exp, pos, stream, PREC_SUFFIX);
+ fprintf (stream, "--");
+ return;
+
+ case UNOP_CAST:
+ (*pos) += 2;
+ if ((int) prec > (int) PREC_PREFIX)
+ fprintf (stream, "(");
+ fprintf (stream, "(");
+ type_print (exp->elts[pc + 1].type, "", stream, 0);
+ fprintf (stream, ") ");
+ print_subexp (exp, pos, stream, PREC_PREFIX);
+ if ((int) prec > (int) PREC_PREFIX)
+ fprintf (stream, ")");
+ return;
+
+ case UNOP_MEMVAL:
+ (*pos) += 2;
+ if ((int) prec > (int) PREC_PREFIX)
+ fprintf (stream, "(");
+ fprintf (stream, "{");
+ type_print (exp->elts[pc + 1].type, "", stream, 0);
+ fprintf (stream, "} ");
+ print_subexp (exp, pos, stream, PREC_PREFIX);
+ if ((int) prec > (int) PREC_PREFIX)
+ fprintf (stream, ")");
+ return;
+
+ case BINOP_ASSIGN_MODIFY:
+ opcode = exp->elts[pc + 1].opcode;
+ (*pos) += 2;
+ myprec = PREC_ASSIGN;
+ assoc = 1;
+ assign_modify = 1;
+ for (tem = 0; tem < sizeof op_print_tab / sizeof op_print_tab[0]; tem++)
+ if (op_print_tab[tem].opcode == opcode)
+ {
+ op_str = op_print_tab[tem].string;
+ break;
+ }
+
+ case OP_THIS:
+ ++(*pos);
+ fprintf (stream, "this");
+ return;
+
+ default:
+ for (tem = 0; tem < sizeof op_print_tab / sizeof op_print_tab[0]; tem++)
+ if (op_print_tab[tem].opcode == opcode)
+ {
+ op_str = op_print_tab[tem].string;
+ myprec = op_print_tab[tem].precedence;
+ assoc = op_print_tab[tem].right_assoc;
+ break;
+ }
+ }
+
+ if ((int) myprec < (int) prec)
+ fprintf (stream, "(");
+ if ((int) opcode > (int) BINOP_END)
+ {
+ /* Unary prefix operator. */
+ fprintf (stream, "%s", op_str);
+ print_subexp (exp, pos, stream, PREC_PREFIX);
+ }
+ else
+ {
+ /* Binary operator. */
+ /* Print left operand.
+ If operator is right-associative,
+ increment precedence for this operand. */
+ print_subexp (exp, pos, stream, (int) myprec + assoc);
+ /* Print the operator itself. */
+ if (assign_modify)
+ fprintf (stream, " %s= ", op_str);
+ else if (op_str[0] == ',')
+ fprintf (stream, "%s ", op_str);
+ else
+ fprintf (stream, " %s ", op_str);
+ /* Print right operand.
+ If operator is left-associative,
+ increment precedence for this operand. */
+ print_subexp (exp, pos, stream, (int) myprec + !assoc);
+ }
+ if ((int) myprec < (int) prec)
+ fprintf (stream, ")");
+}
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