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-rw-r--r--gdb/parse.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/gdb/parse.c b/gdb/parse.c
index fb8793f..7bbe0a8 100644
--- a/gdb/parse.c
+++ b/gdb/parse.c
@@ -399,6 +399,97 @@ write_exp_msymbol (msymbol, text_symbol_type, data_symbol_type)
write_exp_elt_opcode (UNOP_MEMVAL);
}
+/* Recognize tokens that start with '$'. These include:
+
+ $regname A native register name or a "standard
+ register name".
+
+ $variable A convenience variable with a name chosen
+ by the user.
+
+ $digits Value history with index <digits>, starting
+ from the first value which has index 1.
+
+ $$digits Value history with index <digits> relative
+ to the last value. I.E. $$0 is the last
+ value, $$1 is the one previous to that, $$2
+ is the one previous to $$1, etc.
+
+ $ | $0 | $$0 The last value in the value history.
+
+ $$ An abbreviation for the second to the last
+ value in the value history, I.E. $$1
+
+ */
+
+void
+write_dollar_variable (str)
+ struct stoken str;
+{
+ /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1)
+ and $$digits (equivalent to $<-digits> if you could type that). */
+
+ int negate = 0;
+ int i = 1;
+ /* Double dollar means negate the number and add -1 as well.
+ Thus $$ alone means -1. */
+ if (str.length >= 2 && str.ptr[1] == '$')
+ {
+ negate = 1;
+ i = 2;
+ }
+ if (i == str.length)
+ {
+ /* Just dollars (one or two) */
+ i = - negate;
+ goto handle_last;
+ }
+ /* Is the rest of the token digits? */
+ for (; i < str.length; i++)
+ if (!(str.ptr[i] >= '0' && str.ptr[i] <= '9'))
+ break;
+ if (i == str.length)
+ {
+ i = atoi (str.ptr + 1 + negate);
+ if (negate)
+ i = - i;
+ goto handle_last;
+ }
+
+ /* Handle tokens that refer to machine registers:
+ $ followed by a register name. */
+ for (i = 0; i < NUM_REGS; i++)
+ if (str.length - 1 == strlen (reg_names[i])
+ && STREQN (str.ptr + 1, reg_names[i], str.length - 1))
+ {
+ goto handle_register;
+ }
+ for (i = 0; i < num_std_regs; i++)
+ if (str.length - 1 == strlen (std_regs[i].name)
+ && STREQN (str.ptr + 1, std_regs[i].name, str.length - 1))
+ {
+ i = std_regs[i].regnum;
+ goto handle_register;
+ }
+
+ /* Any other names starting in $ are debugger internal variables. */
+
+ write_exp_elt_opcode (OP_INTERNALVAR);
+ write_exp_elt_intern (lookup_internalvar (copy_name (str) + 1));
+ write_exp_elt_opcode (OP_INTERNALVAR);
+ return;
+ handle_last:
+ write_exp_elt_opcode (OP_LAST);
+ write_exp_elt_longcst ((LONGEST) i);
+ write_exp_elt_opcode (OP_LAST);
+ return;
+ handle_register:
+ write_exp_elt_opcode (OP_REGISTER);
+ write_exp_elt_longcst (i);
+ write_exp_elt_opcode (OP_REGISTER);
+ return;
+}
+
/* Return a null-terminated temporary copy of the name
of a string token. */