Re: [PATCH 17/18] introduce block_chainon and use BLOCK_CHAIN more

[Richard Guenther <richard dot guenther at gmail dot com>]

On Fri, Mar 11, 2011 at 5:23 AM, Nathan Froyd <froydnj@codesourcery.com> wrote:
> BLOCKs have a TREE_CHAIN and a TREE_TYPE; TREE_TYPE is useless for
> blocks, but we can't remove TREE_TYPE without also removing TREE_CHAIN.
> This patch lays the groundwork to do just that. ?It changes places that
> use chainon on BLOCKs to use block_chainon, which works identically to
> chainon except it uses BLOCK_CHAIN. ?And it fixes up a few places that
> used TREE_CHAIN when they meant BLOCK_CHAIN.

The middle-end parts are ok.  Any particular reason why you choose
function.[ch] for block_chainon and not tree.[ch]?

Thanks,
Richard.

> -Nathan
>
> gcc/ada/
> ? ? ? ?* gcc-interface/utils.c (gnat_poplevel): Use block_chainon.
>
> gcc/
> ? ? ? ?* function.h (block_chainon): Declare.
> ? ? ? ?* function.c (block_chainon): Define.
>
> gcc/cp/
> ? ? ? ?* decl.c (poplevel): Use block_chainon.
>
> gcc/fortran/
> ? ? ? ?* f95-lang.c (poplevel): Use BLOCK_CHAIN and block_chainon.
>
> gcc/java/
> ? ? ? ?* decl.c (poplevel): Use BLOCK_CHAIN and block_chainon.
>
> diff --git a/gcc/ada/gcc-interface/utils.c b/gcc/ada/gcc-interface/utils.c
> index eac87e0..dd06ca3 100644
> --- a/gcc/ada/gcc-interface/utils.c
> +++ b/gcc/ada/gcc-interface/utils.c
> @@ -395,8 +395,8 @@ gnat_poplevel (void)
> ? else if (BLOCK_VARS (block) == NULL_TREE)
> ? ? {
> ? ? ? BLOCK_SUBBLOCKS (level->chain->block)
> - ? ? ? = chainon (BLOCK_SUBBLOCKS (block),
> - ? ? ? ? ? ? ? ? ?BLOCK_SUBBLOCKS (level->chain->block));
> + ? ? ? = block_chainon (BLOCK_SUBBLOCKS (block),
> + ? ? ? ? ? ? ? ? ? ? ? ?BLOCK_SUBBLOCKS (level->chain->block));
> ? ? ? BLOCK_CHAIN (block) = free_block_chain;
> ? ? ? free_block_chain = block;
> ? ? }
> diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
> index a0ef39f..de96ac2 100644
> --- a/gcc/cp/decl.c
> +++ b/gcc/cp/decl.c
> @@ -794,7 +794,7 @@ poplevel (int keep, int reverse, int functionbody)
> ? ? }
> ? else if (block)
> ? ? current_binding_level->blocks
> - ? ? ?= chainon (current_binding_level->blocks, block);
> + ? ? ?= block_chainon (current_binding_level->blocks, block);
>
> ? /* If we did not make a block for the level just exited,
> ? ? ?any blocks made for inner levels
> @@ -803,7 +803,7 @@ poplevel (int keep, int reverse, int functionbody)
> ? ? ?of something else. ?*/
> ? else if (subblocks)
> ? ? current_binding_level->blocks
> - ? ? ?= chainon (current_binding_level->blocks, subblocks);
> + ? ? ?= block_chainon (current_binding_level->blocks, subblocks);
>
> ? /* Each and every BLOCK node created here in `poplevel' is important
> ? ? ?(e.g. for proper debugging information) so if we created one
> diff --git a/gcc/fortran/f95-lang.c b/gcc/fortran/f95-lang.c
> index 687f60b..aebe397 100644
> --- a/gcc/fortran/f95-lang.c
> +++ b/gcc/fortran/f95-lang.c
> @@ -444,7 +444,7 @@ poplevel (int keep, int reverse, int functionbody)
>
> ? /* Record the BLOCK node just built as the subblock its enclosing scope. ?*/
> ? for (subblock_node = subblock_chain; subblock_node;
> - ? ? ? subblock_node = TREE_CHAIN (subblock_node))
> + ? ? ? subblock_node = BLOCK_CHAIN (subblock_node))
> ? ? BLOCK_SUPERCONTEXT (subblock_node) = block_node;
>
> ? /* Clear out the meanings of the local variables of this level. ?*/
> @@ -475,7 +475,7 @@ poplevel (int keep, int reverse, int functionbody)
> ? else if (block_node)
> ? ? {
> ? ? ? current_binding_level->blocks
> - ? ? ? = chainon (current_binding_level->blocks, block_node);
> + ? ? ? = block_chainon (current_binding_level->blocks, block_node);
> ? ? }
>
> ? /* If we did not make a block for the level just exited, any blocks made for
> @@ -484,7 +484,7 @@ poplevel (int keep, int reverse, int functionbody)
> ? ? ?else. ?*/
> ? else if (subblock_chain)
> ? ? current_binding_level->blocks
> - ? ? ?= chainon (current_binding_level->blocks, subblock_chain);
> + ? ? ?= block_chainon (current_binding_level->blocks, subblock_chain);
> ? if (block_node)
> ? ? TREE_USED (block_node) = 1;
>
> diff --git a/gcc/function.c b/gcc/function.c
> index 3f721fb..094cf74 100644
> --- a/gcc/function.c
> +++ b/gcc/function.c
> @@ -4167,6 +4167,34 @@ blocks_nreverse (tree t)
> ? return prev;
> ?}
>
> +/* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
> + ? by modifying the last node in chain 1 to point to chain 2. ?*/
> +
> +tree
> +block_chainon (tree op1, tree op2)
> +{
> + ?tree t1;
> +
> + ?if (!op1)
> + ? ?return op2;
> + ?if (!op2)
> + ? ?return op1;
> +
> + ?for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
> + ? ?continue;
> + ?BLOCK_CHAIN (t1) = op2;
> +
> +#ifdef ENABLE_TREE_CHECKING
> + ?{
> + ? ?tree t2;
> + ? ?for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
> + ? ? ?gcc_assert (t2 != t1);
> + ?}
> +#endif
> +
> + ?return op1;
> +}
> +
> ?/* Count the subblocks of the list starting with BLOCK. ?If VECTOR is
> ? ?non-NULL, list them all into VECTOR, in a depth-first preorder
> ? ?traversal of the block tree. ?Also clear TREE_ASM_WRITTEN in all
> diff --git a/gcc/function.h b/gcc/function.h
> index 6e7f539..73af294 100644
> --- a/gcc/function.h
> +++ b/gcc/function.h
> @@ -713,6 +713,7 @@ extern void number_blocks (tree);
>
> ?extern void clear_block_marks (tree);
> ?extern tree blocks_nreverse (tree);
> +extern tree block_chainon (tree, tree);
>
> ?/* Return size needed for stack frame based on slots so far allocated.
> ? ?This size counts from zero. ?It is not rounded to STACK_BOUNDARY;
> diff --git a/gcc/java/decl.c b/gcc/java/decl.c
> index a17b826..6e94dff 100644
> --- a/gcc/java/decl.c
> +++ b/gcc/java/decl.c
> @@ -1481,7 +1481,7 @@ poplevel (int keep, int reverse, int functionbody)
>
> ? /* In each subblock, record that this is its superior. ?*/
>
> - ?for (link = subblocks; link; link = TREE_CHAIN (link))
> + ?for (link = subblocks; link; link = BLOCK_CHAIN (link))
> ? ? BLOCK_SUPERCONTEXT (link) = block;
>
> ? /* Clear out the meanings of the local variables of this level. ?*/
> @@ -1545,7 +1545,7 @@ poplevel (int keep, int reverse, int functionbody)
> ? ? ? if (block)
> ? ? ? ?{
> ? ? ? ? ?current_binding_level->blocks
> - ? ? ? ? ? = chainon (current_binding_level->blocks, block);
> + ? ? ? ? ? = block_chainon (current_binding_level->blocks, block);
> ? ? ? ?}
> ? ? ? /* If we did not make a block for the level just exited,
> ? ? ? ? any blocks made for inner levels
> @@ -1554,7 +1554,7 @@ poplevel (int keep, int reverse, int functionbody)
> ? ? ? ? of something else. ?*/
> ? ? ? else if (subblocks)
> ? ? ? ?current_binding_level->blocks
> - ? ? ? ? = chainon (current_binding_level->blocks, subblocks);
> + ? ? ? ? = block_chainon (current_binding_level->blocks, subblocks);
>
> ? ? ? if (bind)
> ? ? ? ?java_add_stmt (bind);
> --
> 1.7.0.4
>
>