Patchwork [v2] Factor out the common code in lookup_{static,global}_symbol

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Submitter Doug Evans via gdb-patches
Date Aug. 5, 2019, 3:33 p.m.
Message ID <20190805153326.95512-1-cbiesinger@google.com>
Download mbox | patch
Permalink /patch/33967/
State New
Headers show

Comments

Doug Evans via gdb-patches - Aug. 5, 2019, 3:33 p.m.
The two functions are extremely similar; this factors out their code into
a shared _internal function.

gdb/ChangeLog:

2019-08-02  Christian Biesinger  <cbiesinger@google.com>

	* symtab.c (lookup_static_symbol): Call the new function (and move
	it down to be next to lookup_global_symbol).
	(struct global_sym_lookup_data): Add block_enum member.
	(lookup_symbol_global_iterator_cb): Pass block_index instead of
	GLOBAL_BLOCK to lookup_symbol_in_objfile.
	(lookup_global_symbol_internal): New function.
	(lookup_global_symbol): Call new function.
---
 gdb/symtab.c | 82 ++++++++++++++++++++++++----------------------------
 1 file changed, 37 insertions(+), 45 deletions(-)
Doug Evans via gdb-patches - Aug. 16, 2019, 5:40 p.m.
On Mon, Aug 5, 2019 at 10:33 AM Christian Biesinger
<cbiesinger@google.com> wrote:
>
> The two functions are extremely similar; this factors out their code into
> a shared _internal function.
>
> gdb/ChangeLog:
>
> 2019-08-02  Christian Biesinger  <cbiesinger@google.com>
>
>         * symtab.c (lookup_static_symbol): Call the new function (and move
>         it down to be next to lookup_global_symbol).
>         (struct global_sym_lookup_data): Add block_enum member.
>         (lookup_symbol_global_iterator_cb): Pass block_index instead of
>         GLOBAL_BLOCK to lookup_symbol_in_objfile.
>         (lookup_global_symbol_internal): New function.
>         (lookup_global_symbol): Call new function.
> ---
>  gdb/symtab.c | 82 ++++++++++++++++++++++++----------------------------
>  1 file changed, 37 insertions(+), 45 deletions(-)
>
> diff --git a/gdb/symtab.c b/gdb/symtab.c
> index 87a0c8e4da..1a5a6bf20e 100644
> --- a/gdb/symtab.c
> +++ b/gdb/symtab.c
> @@ -2566,44 +2566,6 @@ lookup_symbol_in_objfile (struct objfile *objfile, enum block_enum block_index,
>    return result;
>  }
>
> -/* See symtab.h.  */
> -
> -struct block_symbol
> -lookup_static_symbol (const char *name, const domain_enum domain)
> -{
> -  struct symbol_cache *cache = get_symbol_cache (current_program_space);
> -  struct block_symbol result;
> -  struct block_symbol_cache *bsc;
> -  struct symbol_cache_slot *slot;
> -
> -  /* Lookup in STATIC_BLOCK is not current-objfile-dependent, so just pass
> -     NULL for OBJFILE_CONTEXT.  */
> -  result = symbol_cache_lookup (cache, NULL, STATIC_BLOCK, name, domain,
> -                               &bsc, &slot);
> -  if (result.symbol != NULL)
> -    {
> -      if (SYMBOL_LOOKUP_FAILED_P (result))
> -       return {};
> -      return result;
> -    }
> -
> -  for (objfile *objfile : current_program_space->objfiles ())
> -    {
> -      result = lookup_symbol_in_objfile (objfile, STATIC_BLOCK, name, domain);
> -      if (result.symbol != NULL)
> -       {
> -         /* Still pass NULL for OBJFILE_CONTEXT here.  */
> -         symbol_cache_mark_found (bsc, slot, NULL, result.symbol,
> -                                  result.block);
> -         return result;
> -       }
> -    }
> -
> -  /* Still pass NULL for OBJFILE_CONTEXT here.  */
> -  symbol_cache_mark_not_found (bsc, slot, NULL, name, domain);
> -  return {};
> -}
> -
>  /* Private data to be used with lookup_symbol_global_iterator_cb.  */
>
>  struct global_sym_lookup_data
> @@ -2614,6 +2576,9 @@ struct global_sym_lookup_data
>    /* The domain to use for our search.  */
>    domain_enum domain;
>
> +  /* The block index in which to search */
> +  enum block_enum block_index;
> +
>    /* The field where the callback should store the symbol if found.
>       It should be initialized to {NULL, NULL} before the search is started.  */
>    struct block_symbol result;
> @@ -2634,7 +2599,7 @@ lookup_symbol_global_iterator_cb (struct objfile *objfile,
>    gdb_assert (data->result.symbol == NULL
>               && data->result.block == NULL);
>
> -  data->result = lookup_symbol_in_objfile (objfile, GLOBAL_BLOCK,
> +  data->result = lookup_symbol_in_objfile (objfile, data->block_index,
>                                            data->name, data->domain);
>
>    /* If we found a match, tell the iterator to stop.  Otherwise,
> @@ -2642,12 +2607,15 @@ lookup_symbol_global_iterator_cb (struct objfile *objfile,
>    return (data->result.symbol != NULL);
>  }
>
> -/* See symtab.h.  */
> +/* This function contains the common code of lookup_{global,static}_symbol.
> +   BLOCK is only used if BLOCK_INDEX is GLOBAL_SCOPE, in which case it is
> +   used to retrieve the objfile to start the lookup in.  */
>
> -struct block_symbol
> -lookup_global_symbol (const char *name,
> -                     const struct block *block,
> -                     const domain_enum domain)
> +static struct block_symbol
> +lookup_global_symbol_internal (const char *name,
> +                              enum block_enum block_index,
> +                              const struct block *block,
> +                              const domain_enum domain)
>  {
>    struct symbol_cache *cache = get_symbol_cache (current_program_space);
>    struct block_symbol result;
> @@ -2656,11 +2624,14 @@ lookup_global_symbol (const char *name,
>    struct block_symbol_cache *bsc;
>    struct symbol_cache_slot *slot;
>
> +  gdb_assert (block_index == GLOBAL_BLOCK || block_index == STATIC_BLOCK);
> +  gdb_assert (block == nullptr || block_index == GLOBAL_BLOCK);
> +
>    objfile = lookup_objfile_from_block (block);
>
>    /* First see if we can find the symbol in the cache.
>       This works because we use the current objfile to qualify the lookup.  */
> -  result = symbol_cache_lookup (cache, objfile, GLOBAL_BLOCK, name, domain,
> +  result = symbol_cache_lookup (cache, objfile, block_index, name, domain,
>                                 &bsc, &slot);
>    if (result.symbol != NULL)
>      {
> @@ -2678,6 +2649,7 @@ lookup_global_symbol (const char *name,
>      {
>        memset (&lookup_data, 0, sizeof (lookup_data));
>        lookup_data.name = name;
> +      lookup_data.block_index = block_index;
>        lookup_data.domain = domain;
>        gdbarch_iterate_over_objfiles_in_search_order
>         (objfile != NULL ? get_objfile_arch (objfile) : target_gdbarch (),
> @@ -2693,6 +2665,26 @@ lookup_global_symbol (const char *name,
>    return result;
>  }
>
> +/* See symtab.h.  */
> +
> +struct block_symbol
> +lookup_static_symbol (const char *name, const domain_enum domain)
> +{
> +  /* TODO: Should static symbol lookup start with a block as well, so we can
> +     prefer a static symbol in the current CU?  */
> +  return lookup_global_symbol_internal (name, STATIC_BLOCK, nullptr, domain);
> +}
> +
> +/* See symtab.h.  */
> +
> +struct block_symbol
> +lookup_global_symbol (const char *name,
> +                     const struct block *block,
> +                     const domain_enum domain)
> +{
> +  return lookup_global_symbol_internal (name, GLOBAL_BLOCK, block, domain);
> +}
> +
>  int
>  symbol_matches_domain (enum language symbol_language,
>                        domain_enum symbol_domain,
> --
> 2.22.0.770.g0f2c4a37fd-goog
>

Patch

diff --git a/gdb/symtab.c b/gdb/symtab.c
index 87a0c8e4da..1a5a6bf20e 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -2566,44 +2566,6 @@  lookup_symbol_in_objfile (struct objfile *objfile, enum block_enum block_index,
   return result;
 }
 
-/* See symtab.h.  */
-
-struct block_symbol
-lookup_static_symbol (const char *name, const domain_enum domain)
-{
-  struct symbol_cache *cache = get_symbol_cache (current_program_space);
-  struct block_symbol result;
-  struct block_symbol_cache *bsc;
-  struct symbol_cache_slot *slot;
-
-  /* Lookup in STATIC_BLOCK is not current-objfile-dependent, so just pass
-     NULL for OBJFILE_CONTEXT.  */
-  result = symbol_cache_lookup (cache, NULL, STATIC_BLOCK, name, domain,
-				&bsc, &slot);
-  if (result.symbol != NULL)
-    {
-      if (SYMBOL_LOOKUP_FAILED_P (result))
-	return {};
-      return result;
-    }
-
-  for (objfile *objfile : current_program_space->objfiles ())
-    {
-      result = lookup_symbol_in_objfile (objfile, STATIC_BLOCK, name, domain);
-      if (result.symbol != NULL)
-	{
-	  /* Still pass NULL for OBJFILE_CONTEXT here.  */
-	  symbol_cache_mark_found (bsc, slot, NULL, result.symbol,
-				   result.block);
-	  return result;
-	}
-    }
-
-  /* Still pass NULL for OBJFILE_CONTEXT here.  */
-  symbol_cache_mark_not_found (bsc, slot, NULL, name, domain);
-  return {};
-}
-
 /* Private data to be used with lookup_symbol_global_iterator_cb.  */
 
 struct global_sym_lookup_data
@@ -2614,6 +2576,9 @@  struct global_sym_lookup_data
   /* The domain to use for our search.  */
   domain_enum domain;
 
+  /* The block index in which to search */
+  enum block_enum block_index;
+
   /* The field where the callback should store the symbol if found.
      It should be initialized to {NULL, NULL} before the search is started.  */
   struct block_symbol result;
@@ -2634,7 +2599,7 @@  lookup_symbol_global_iterator_cb (struct objfile *objfile,
   gdb_assert (data->result.symbol == NULL
 	      && data->result.block == NULL);
 
-  data->result = lookup_symbol_in_objfile (objfile, GLOBAL_BLOCK,
+  data->result = lookup_symbol_in_objfile (objfile, data->block_index,
 					   data->name, data->domain);
 
   /* If we found a match, tell the iterator to stop.  Otherwise,
@@ -2642,12 +2607,15 @@  lookup_symbol_global_iterator_cb (struct objfile *objfile,
   return (data->result.symbol != NULL);
 }
 
-/* See symtab.h.  */
+/* This function contains the common code of lookup_{global,static}_symbol.
+   BLOCK is only used if BLOCK_INDEX is GLOBAL_SCOPE, in which case it is
+   used to retrieve the objfile to start the lookup in.  */
 
-struct block_symbol
-lookup_global_symbol (const char *name,
-		      const struct block *block,
-		      const domain_enum domain)
+static struct block_symbol
+lookup_global_symbol_internal (const char *name,
+			       enum block_enum block_index,
+			       const struct block *block,
+			       const domain_enum domain)
 {
   struct symbol_cache *cache = get_symbol_cache (current_program_space);
   struct block_symbol result;
@@ -2656,11 +2624,14 @@  lookup_global_symbol (const char *name,
   struct block_symbol_cache *bsc;
   struct symbol_cache_slot *slot;
 
+  gdb_assert (block_index == GLOBAL_BLOCK || block_index == STATIC_BLOCK);
+  gdb_assert (block == nullptr || block_index == GLOBAL_BLOCK);
+
   objfile = lookup_objfile_from_block (block);
 
   /* First see if we can find the symbol in the cache.
      This works because we use the current objfile to qualify the lookup.  */
-  result = symbol_cache_lookup (cache, objfile, GLOBAL_BLOCK, name, domain,
+  result = symbol_cache_lookup (cache, objfile, block_index, name, domain,
 				&bsc, &slot);
   if (result.symbol != NULL)
     {
@@ -2678,6 +2649,7 @@  lookup_global_symbol (const char *name,
     {
       memset (&lookup_data, 0, sizeof (lookup_data));
       lookup_data.name = name;
+      lookup_data.block_index = block_index;
       lookup_data.domain = domain;
       gdbarch_iterate_over_objfiles_in_search_order
 	(objfile != NULL ? get_objfile_arch (objfile) : target_gdbarch (),
@@ -2693,6 +2665,26 @@  lookup_global_symbol (const char *name,
   return result;
 }
 
+/* See symtab.h.  */
+
+struct block_symbol
+lookup_static_symbol (const char *name, const domain_enum domain)
+{
+  /* TODO: Should static symbol lookup start with a block as well, so we can
+     prefer a static symbol in the current CU?  */
+  return lookup_global_symbol_internal (name, STATIC_BLOCK, nullptr, domain);
+}
+
+/* See symtab.h.  */
+
+struct block_symbol
+lookup_global_symbol (const char *name,
+		      const struct block *block,
+		      const domain_enum domain)
+{
+  return lookup_global_symbol_internal (name, GLOBAL_BLOCK, block, domain);
+}
+
 int
 symbol_matches_domain (enum language symbol_language,
 		       domain_enum symbol_domain,