import gdb-1999-10-11 snapshot

[deliverable/binutils-gdb.git] / gdb / parse.c

diff --git a/gdb/parse.c b/gdb/parse.c
index b178465db0b2ffc3587c2ab9ecbbdab01b3eaf30..271e2029936fd5f687a03a0b7a52cf2e7cb04921 100644 (file)
--- a/gdb/parse.c
+++ b/gdb/parse.c
@@ -43,6 +43,21 @@
 #include "parser-defs.h"
 #include "gdbcmd.h"
 #include "symfile.h"           /* for overlay functions */
+\f
+/* Symbols which architectures can redefine.  */
+
+/* Some systems have routines whose names start with `$'.  Giving this
+   macro a non-zero value tells GDB's expression parser to check for
+   such routines when parsing tokens that begin with `$'.
+
+   On HP-UX, certain system routines (millicode) have names beginning
+   with `$' or `$$'.  For example, `$$dyncall' is a millicode routine
+   that handles inter-space procedure calls on PA-RISC.  */
+#ifndef SYMBOLS_CAN_START_WITH_DOLLAR
+#define SYMBOLS_CAN_START_WITH_DOLLAR (0)
+#endif
+
+
 \f
 /* Global variables declared in parser-defs.h (and commented there).  */
 struct expression *expout;
@@ -460,9 +475,6 @@ write_dollar_variable (str)
   /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1)
      and $$digits (equivalent to $<-digits> if you could type that). */
 
-  struct symbol *sym = NULL;
-  struct minimal_symbol *msym = NULL;
-
   int negate = 0;
   int i = 1;
   /* Double dollar means negate the number and add -1 as well.
@@ -496,27 +508,36 @@ write_dollar_variable (str)
   if (i >= 0)
     goto handle_register;
 
-  /* On HP-UX, certain system routines (millicode) have names beginning
-     with $ or $$, e.g. $$dyncall, which handles inter-space procedure
-     calls on PA-RISC. Check for those, first. */
-
-  sym = lookup_symbol (copy_name (str), (struct block *) NULL,
-                      VAR_NAMESPACE, (int *) NULL, (struct symtab **) NULL);
-  if (sym)
+  if (SYMBOLS_CAN_START_WITH_DOLLAR)
     {
-      write_exp_elt_opcode (OP_VAR_VALUE);
-      write_exp_elt_block (block_found);       /* set by lookup_symbol */
-      write_exp_elt_sym (sym);
-      write_exp_elt_opcode (OP_VAR_VALUE);
-      return;
-    }
-  msym = lookup_minimal_symbol (copy_name (str), NULL, NULL);
-  if (msym)
-    {
-      write_exp_msymbol (msym,
-                        lookup_function_type (builtin_type_int),
-                        builtin_type_int);
-      return;
+      struct symbol *sym = NULL;
+      struct minimal_symbol *msym = NULL;
+
+      /* On HP-UX, certain system routines (millicode) have names beginning
+        with $ or $$, e.g. $$dyncall, which handles inter-space procedure
+        calls on PA-RISC. Check for those, first. */
+
+      /* This code is not enabled on non HP-UX systems, since worst case 
+        symbol table lookup performance is awful, to put it mildly. */
+
+      sym = lookup_symbol (copy_name (str), (struct block *) NULL,
+                          VAR_NAMESPACE, (int *) NULL, (struct symtab **) NULL);
+      if (sym)
+       {
+         write_exp_elt_opcode (OP_VAR_VALUE);
+         write_exp_elt_block (block_found);    /* set by lookup_symbol */
+         write_exp_elt_sym (sym);
+         write_exp_elt_opcode (OP_VAR_VALUE);
+         return;
+       }
+      msym = lookup_minimal_symbol (copy_name (str), NULL, NULL);
+      if (msym)
+       {
+         write_exp_msymbol (msym,
+                            lookup_function_type (builtin_type_int),
+                            builtin_type_int);
+         return;
+       }
     }
 
   /* Any other names starting in $ are debugger internal variables.  */