Extend SystemTap SDT probe argument parser

This patch extends the current generic parser for SystemTap SDT probe
arguments.  It can be almost considered a cleanup, but the main point of
it is actually to allow the generic parser to accept multiple prefixes
and suffixes for the its operands (i.e., integers, register names, and
register indirection).

I have chosen to implement this as a list of const strings, and declare
this list as "static" inside each target's method used to initialize
gdbarch.

This patch is actually a preparation for an upcoming patch for ARM,
which implements the support for multiple integer prefixes (as defined
by ARM's asm spec).  And AArch64 will also need this, for the same
reason.

This patch was regtested on all architectures that it touches (i.e.,
i386, x86_64, ARM, PPC/PPC64, s390x and IA-64).  No regressions were found.

2013-12-19  Sergio Durigan Junior  <sergiodj@redhat.com>

	* amd64-tdep.c (amd64_init_abi): Declare SystemTap SDT probe
	argument prefixes and suffixes.  Initialize gdbarch with them.
	* arm-linux-tdep.c (arm_linux_init_abi): Likewise.
	* gdbarch.c: Regenerate.
	* gdbarch.h: Regenerate.
	* gdbarch.sh (stap_integer_prefix, stap_integer_suffix)
	(stap_register_prefix, stap_register_suffix)
	(stap_register_indirection_prefix)
	(stap_register_indirection_suffix): Declare as "const char *const
	*" instead of "const char *".  Adjust printing function.  Rename
	all of the variables to the plural.
	(pstring_list): New function.
	* i386-tdep.c (i386_elf_init_abi): Declare SystemTap SDT probe
	argument prefixes and suffixes.  Initialize gdbarch with them.
	* ia64-linux-tdep.c (ia64_linux_init_abi): Likewise.
	* ppc-linux-tdep.c (ppc_linux_init_abi): Likewise.
	* s390-linux-tdep.c (s390_gdbarch_init): Likewise.
	* stap-probe.c (stap_is_generic_prefix): New function.
	(stap_is_register_prefix): Likewise.
	(stap_is_register_indirection_prefix): Likewise.
	(stap_is_integer_prefix): Likewise.
	(stap_generic_check_suffix): Likewise.
	(stap_check_integer_suffix): Likewise.
	(stap_check_register_suffix): Likewise.
	(stap_check_register_indirection_suffix): Likewise.
	(stap_parse_register_operand): Remove unecessary declarations for
	variables holding prefix and suffix information.  Use the new
	functions listed above for checking for prefixes and suffixes.
	(stap_parse_single_operand): Likewise.

1 files changed, 234 insertions, 77 deletions

diff --git a/gdb/stap-probe.c b/gdb/stap-probe.c
index 33d4569..1d942550 100644
--- a/gdb/stap-probe.c
+++ b/gdb/stap-probe.c
@@ -346,6 +346,191 @@ stap_get_expected_argument_type (struct gdbarch *gdbarch,
     }
 }
 
+/* Helper function to check for a generic list of prefixes.  GDBARCH
+   is the current gdbarch being used.  S is the expression being
+   analyzed.  If R is not NULL, it will be used to return the found
+   prefix.  PREFIXES is the list of expected prefixes.
+
+   This function does a case-insensitive match.
+
+   Return 1 if any prefix has been found, zero otherwise.  */
+
+static int
+stap_is_generic_prefix (struct gdbarch *gdbarch, const char *s,
+			const char **r, const char *const *prefixes)
+{
+  const char *const *p;
+
+  if (prefixes == NULL)
+    {
+      if (r != NULL)
+	*r = "";
+
+      return 1;
+    }
+
+  for (p = prefixes; *p != NULL; ++p)
+    {
+      if (strncasecmp (s, *p, strlen (*p)) == 0)
+	{
+	  if (r != NULL)
+	    *r = *p;
+
+	  return 1;
+	}
+    }
+
+  return 0;
+}
+
+/* Return 1 if S points to a register prefix, zero otherwise.  For a
+   description of the arguments, look at stap_is_generic_prefix.  */
+
+static int
+stap_is_register_prefix (struct gdbarch *gdbarch, const char *s,
+			 const char **r)
+{
+  const char *const *t = gdbarch_stap_register_prefixes (gdbarch);
+
+  return stap_is_generic_prefix (gdbarch, s, r, t);
+}
+
+/* Return 1 if S points to a register indirection prefix, zero
+   otherwise.  For a description of the arguments, look at
+   stap_is_generic_prefix.  */
+
+static int
+stap_is_register_indirection_prefix (struct gdbarch *gdbarch, const char *s,
+				     const char **r)
+{
+  const char *const *t = gdbarch_stap_register_indirection_prefixes (gdbarch);
+
+  return stap_is_generic_prefix (gdbarch, s, r, t);
+}
+
+/* Return 1 if S points to an integer prefix, zero otherwise.  For a
+   description of the arguments, look at stap_is_generic_prefix.
+
+   This function takes care of analyzing whether we are dealing with
+   an expected integer prefix, or, if there is no integer prefix to be
+   expected, whether we are dealing with a digit.  It does a
+   case-insensitive match.  */
+
+static int
+stap_is_integer_prefix (struct gdbarch *gdbarch, const char *s,
+			const char **r)
+{
+  const char *const *t = gdbarch_stap_integer_prefixes (gdbarch);
+  const char *const *p;
+
+  if (t == NULL)
+    {
+      /* A NULL value here means that integers do not have a prefix.
+	 We just check for a digit then.  */
+      if (r != NULL)
+	*r = "";
+
+      return isdigit (*s);
+    }
+
+  for (p = t; *p != NULL; ++p)
+    {
+      size_t len = strlen (*p);
+
+      if ((len == 0 && isdigit (*s))
+	  || (len > 0 && strncasecmp (s, *p, len) == 0))
+	{
+	  /* Integers may or may not have a prefix.  The "len == 0"
+	     check covers the case when integers do not have a prefix
+	     (therefore, we just check if we have a digit).  The call
+	     to "strncasecmp" covers the case when they have a
+	     prefix.  */
+	  if (r != NULL)
+	    *r = *p;
+
+	  return 1;
+	}
+    }
+
+  return 0;
+}
+
+/* Helper function to check for a generic list of suffixes.  If we are
+   not expecting any suffixes, then it just returns 1.  If we are
+   expecting at least one suffix, then it returns 1 if a suffix has
+   been found, zero otherwise.  GDBARCH is the current gdbarch being
+   used.  S is the expression being analyzed.  If R is not NULL, it
+   will be used to return the found suffix.  SUFFIXES is the list of
+   expected suffixes.  This function does a case-insensitive
+   match.  */
+
+static int
+stap_generic_check_suffix (struct gdbarch *gdbarch, const char *s,
+			   const char **r, const char *const *suffixes)
+{
+  const char *const *p;
+  int found = 0;
+
+  if (suffixes == NULL)
+    {
+      if (r != NULL)
+	*r = "";
+
+      return 1;
+    }
+
+  for (p = suffixes; *p != NULL; ++p)
+    if (strncasecmp (s, *p, strlen (*p)) == 0)
+      {
+	if (r != NULL)
+	  *r = *p;
+
+	found = 1;
+	break;
+      }
+
+  return found;
+}
+
+/* Return 1 if S points to an integer suffix, zero otherwise.  For a
+   description of the arguments, look at
+   stap_generic_check_suffix.  */
+
+static int
+stap_check_integer_suffix (struct gdbarch *gdbarch, const char *s,
+			   const char **r)
+{
+  const char *const *p = gdbarch_stap_integer_suffixes (gdbarch);
+
+  return stap_generic_check_suffix (gdbarch, s, r, p);
+}
+
+/* Return 1 if S points to a register suffix, zero otherwise.  For a
+   description of the arguments, look at
+   stap_generic_check_suffix.  */
+
+static int
+stap_check_register_suffix (struct gdbarch *gdbarch, const char *s,
+			    const char **r)
+{
+  const char *const *p = gdbarch_stap_register_suffixes (gdbarch);
+
+  return stap_generic_check_suffix (gdbarch, s, r, p);
+}
+
+/* Return 1 if S points to a register indirection suffix, zero
+   otherwise.  For a description of the arguments, look at
+   stap_generic_check_suffix.  */
+
+static int
+stap_check_register_indirection_suffix (struct gdbarch *gdbarch, const char *s,
+					const char **r)
+{
+  const char *const *p = gdbarch_stap_register_indirection_suffixes (gdbarch);
+
+  return stap_generic_check_suffix (gdbarch, s, r, p);
+}
+
 /* Function responsible for parsing a register operand according to
    SystemTap parlance.  Assuming:
 
@@ -385,24 +570,14 @@ stap_parse_register_operand (struct stap_parse_info *p)
   const char *start;
   char *regname;
   int len;
-
-  /* Prefixes for the parser.  */
-  const char *reg_prefix = gdbarch_stap_register_prefix (gdbarch);
-  const char *reg_ind_prefix
-    = gdbarch_stap_register_indirection_prefix (gdbarch);
   const char *gdb_reg_prefix = gdbarch_stap_gdb_register_prefix (gdbarch);
-  int reg_prefix_len = reg_prefix ? strlen (reg_prefix) : 0;
-  int reg_ind_prefix_len = reg_ind_prefix ? strlen (reg_ind_prefix) : 0;
   int gdb_reg_prefix_len = gdb_reg_prefix ? strlen (gdb_reg_prefix) : 0;
-
-  /* Suffixes for the parser.  */
-  const char *reg_suffix = gdbarch_stap_register_suffix (gdbarch);
-  const char *reg_ind_suffix
-    = gdbarch_stap_register_indirection_suffix (gdbarch);
   const char *gdb_reg_suffix = gdbarch_stap_gdb_register_suffix (gdbarch);
-  int reg_suffix_len = reg_suffix ? strlen (reg_suffix) : 0;
-  int reg_ind_suffix_len = reg_ind_suffix ? strlen (reg_ind_suffix) : 0;
   int gdb_reg_suffix_len = gdb_reg_suffix ? strlen (gdb_reg_suffix) : 0;
+  const char *reg_prefix;
+  const char *reg_ind_prefix;
+  const char *reg_suffix;
+  const char *reg_ind_suffix;
 
   /* Checking for a displacement argument.  */
   if (*p->arg == '+')
@@ -438,11 +613,10 @@ stap_parse_register_operand (struct stap_parse_info *p)
     }
 
   /* Getting rid of register indirection prefix.  */
-  if (reg_ind_prefix
-      && strncmp (p->arg, reg_ind_prefix, reg_ind_prefix_len) == 0)
+  if (stap_is_register_indirection_prefix (gdbarch, p->arg, &reg_ind_prefix))
     {
       indirect_p = 1;
-      p->arg += reg_ind_prefix_len;
+      p->arg += strlen (reg_ind_prefix);
     }
 
   if (disp_p && !indirect_p)
@@ -450,8 +624,8 @@ stap_parse_register_operand (struct stap_parse_info *p)
 	   p->saved_arg);
 
   /* Getting rid of register prefix.  */
-  if (reg_prefix && strncmp (p->arg, reg_prefix, reg_prefix_len) == 0)
-    p->arg += reg_prefix_len;
+  if (stap_is_register_prefix (gdbarch, p->arg, &reg_prefix))
+    p->arg += strlen (reg_prefix);
 
   /* Now we should have only the register name.  Let's extract it and get
      the associated number.  */
@@ -509,23 +683,21 @@ stap_parse_register_operand (struct stap_parse_info *p)
     }
 
   /* Getting rid of the register name suffix.  */
-  if (reg_suffix)
-    {
-      if (strncmp (p->arg, reg_suffix, reg_suffix_len) != 0)
-	error (_("Missing register name suffix `%s' on expression `%s'."),
-	       reg_suffix, p->saved_arg);
-
-      p->arg += reg_suffix_len;
-    }
+  if (stap_check_register_suffix (gdbarch, p->arg, &reg_suffix))
+    p->arg += strlen (reg_suffix);
+  else
+    error (_("Missing register name suffix on expression `%s'."),
+	   p->saved_arg);
 
   /* Getting rid of the register indirection suffix.  */
-  if (indirect_p && reg_ind_suffix)
+  if (indirect_p)
     {
-      if (strncmp (p->arg, reg_ind_suffix, reg_ind_suffix_len) != 0)
-	error (_("Missing indirection suffix `%s' on expression `%s'."),
-	       reg_ind_suffix, p->saved_arg);
-
-      p->arg += reg_ind_suffix_len;
+      if (stap_check_register_indirection_suffix (gdbarch, p->arg,
+						  &reg_ind_suffix))
+	p->arg += strlen (reg_ind_suffix);
+      else
+	error (_("Missing indirection suffix on expression `%s'."),
+	       p->saved_arg);
     }
 }
 
@@ -548,19 +720,7 @@ static void
 stap_parse_single_operand (struct stap_parse_info *p)
 {
   struct gdbarch *gdbarch = p->gdbarch;
-
-  /* Prefixes for the parser.  */
-  const char *const_prefix = gdbarch_stap_integer_prefix (gdbarch);
-  const char *reg_prefix = gdbarch_stap_register_prefix (gdbarch);
-  const char *reg_ind_prefix
-    = gdbarch_stap_register_indirection_prefix (gdbarch);
-  int const_prefix_len = const_prefix ? strlen (const_prefix) : 0;
-  int reg_prefix_len = reg_prefix ? strlen (reg_prefix) : 0;
-  int reg_ind_prefix_len = reg_ind_prefix ? strlen (reg_ind_prefix) : 0;
-
-  /* Suffixes for the parser.  */
-  const char *const_suffix = gdbarch_stap_integer_suffix (gdbarch);
-  int const_suffix_len = const_suffix ? strlen (const_suffix) : 0;
+  const char *int_prefix = NULL;
 
   /* We first try to parse this token as a "special token".  */
   if (gdbarch_stap_parse_special_token_p (gdbarch))
@@ -607,8 +767,7 @@ stap_parse_single_operand (struct stap_parse_info *p)
 	  tmp = endp;
 	}
 
-      if (!reg_ind_prefix
-	  || strncmp (tmp, reg_ind_prefix, reg_ind_prefix_len) != 0)
+      if (!stap_is_register_indirection_prefix (gdbarch, tmp, NULL))
 	{
 	  /* This is not a displacement.  We skip the operator, and deal
 	     with it later.  */
@@ -637,16 +796,23 @@ stap_parse_single_operand (struct stap_parse_info *p)
       char *endp;
       long number;
 
-      /* We can be dealing with a numeric constant (if `const_prefix' is
-	 NULL), or with a register displacement.  */
+      /* We can be dealing with a numeric constant, or with a register
+	 displacement.  */
       number = strtol (tmp, &endp, 10);
       tmp = endp;
 
       if (p->inside_paren_p)
 	tmp = skip_spaces_const (tmp);
-      if (!const_prefix && reg_ind_prefix
-	  && strncmp (tmp, reg_ind_prefix, reg_ind_prefix_len) != 0)
+
+      /* If "stap_is_integer_prefix" returns true, it means we can
+	 accept integers without a prefix here.  But we also need to
+	 check whether the next token (i.e., "tmp") is not a register
+	 indirection prefix.  */
+      if (stap_is_integer_prefix (gdbarch, p->arg, NULL)
+	  && !stap_is_register_indirection_prefix (gdbarch, tmp, NULL))
 	{
+	  const char *int_suffix;
+
 	  /* We are dealing with a numeric constant.  */
 	  write_exp_elt_opcode (OP_LONG);
 	  write_exp_elt_type (builtin_type (gdbarch)->builtin_long);
@@ -655,30 +821,26 @@ stap_parse_single_operand (struct stap_parse_info *p)
 
 	  p->arg = tmp;
 
-	  if (const_suffix)
-	    {
-	      if (strncmp (p->arg, const_suffix, const_suffix_len) == 0)
-		p->arg += const_suffix_len;
-	      else
-		error (_("Invalid constant suffix on expression `%s'."),
-		       p->saved_arg);
-	    }
+	  if (stap_check_integer_suffix (gdbarch, p->arg, &int_suffix))
+	    p->arg += strlen (int_suffix);
+	  else
+	    error (_("Invalid constant suffix on expression `%s'."),
+		   p->saved_arg);
 	}
-      else if (reg_ind_prefix
-	       && strncmp (tmp, reg_ind_prefix, reg_ind_prefix_len) == 0)
+      else if (stap_is_register_indirection_prefix (gdbarch, tmp, NULL))
 	stap_parse_register_operand (p);
       else
 	error (_("Unknown numeric token on expression `%s'."),
 	       p->saved_arg);
     }
-  else if (const_prefix
-	   && strncmp (p->arg, const_prefix, const_prefix_len) == 0)
+  else if (stap_is_integer_prefix (gdbarch, p->arg, &int_prefix))
     {
       /* We are dealing with a numeric constant.  */
       long number;
       char *endp;
+      const char *int_suffix;
 
-      p->arg += const_prefix_len;
+      p->arg += strlen (int_prefix);
       number = strtol (p->arg, &endp, 10);
       p->arg = endp;
 
@@ -687,19 +849,14 @@ stap_parse_single_operand (struct stap_parse_info *p)
       write_exp_elt_longcst (number);
       write_exp_elt_opcode (OP_LONG);
 
-      if (const_suffix)
-	{
-	  if (strncmp (p->arg, const_suffix, const_suffix_len) == 0)
-	    p->arg += const_suffix_len;
-	  else
-	    error (_("Invalid constant suffix on expression `%s'."),
-		   p->saved_arg);
-	}
+      if (stap_check_integer_suffix (gdbarch, p->arg, &int_suffix))
+	p->arg += strlen (int_suffix);
+      else
+	error (_("Invalid constant suffix on expression `%s'."),
+	       p->saved_arg);
     }
-  else if ((reg_prefix
-	    && strncmp (p->arg, reg_prefix, reg_prefix_len) == 0)
-	   || (reg_ind_prefix
-	       && strncmp (p->arg, reg_ind_prefix, reg_ind_prefix_len) == 0))
+  else if (stap_is_register_prefix (gdbarch, p->arg, NULL)
+	   || stap_is_register_indirection_prefix (gdbarch, p->arg, NULL))
     stap_parse_register_operand (p);
   else
     error (_("Operator `%c' not recognized on expression `%s'."),