This patch conveys information about the blocks/edges in a jump
threading path. Of particular interest is information about the source
block in each edge of the path -- the nature of the block determines our
copy strategy (empty -- no copy, normal copy, joiner copy).
Rather than rediscover the nature of those blocks during the CFG/SSA
graph updating, it's easier to just attach the information to each edge
in the path. That's precisely what this patch does.
The SSA/CFG updating code isn't making much use of this yet, that's a
follow-on change. This change is strictly designed to get the
information into the updating code.
Bootstrapped and regression tested on x86_64-unknown-linux-gnu.
Installed on trunk.
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5adbaeb..8871aca 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,26 @@
+2013-09-25 Jeff Law l...@redhat.com
+
+ * tree-flow.h (thread_through_all_blocks): Prototype moved into
+ tree-ssa-threadupdate.h.
+ (register_jump_thread): Similarly.
+ * tree-ssa-threadupdate.h: New header file.
+ * tree-ssa-dom.c: Include tree-ssa-threadupdate.h.
+ * tree-vrp.c: Likewise.
+ * tree-ssa-threadedge.c: Include tree-ssa-threadupdate.h.
+ (thread_around_empty_blocks): Change type of path vector argument to
+ an edge,type pair from just an edge. Initialize both elements when
+ appending to a jump threading path. Tweak references to elements
+ appropriately.
+ (thread_across_edge): Similarly. Release memory for the elements
+ as needed.
+ * tree-ssa-threadupdate.c: Include tree-ssa-threadupdate.h.
+ (dump_jump_thread_path): New function broken out from
+ register_jump_thread.
+ (register_jump_thread): Use dump_jump_thread_path. Change type of
+ path vector entries. Search the path for NULL edges and dump
+ the path if one is found. Tweak the conversion of path to 3-edge
+ form to use the block copy type information embedded in the path.
+
2013-09-25 Yvan Roux yvan.r...@linaro.org
* lra.c (update_inc_notes): Remove all REG_DEAD and REG_UNUSED notes.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 634e747..a264056 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,6 @@
+2013-09-25 Jeff Law l...@redhat.com
+
+ * gcc.dg/tree-ssa/ssa-dom-thread-3.c: Update expected output.
2013-09-25 Tobias Burnus bur...@net-b.de
PR fortran/58436
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-dom-thread-3.c
b/gcc/testsuite/gcc.dg/tree-ssa/ssa-dom-thread-3.c
index d2a1fbb..222a97b 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/ssa-dom-thread-3.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-dom-thread-3.c
@@ -43,7 +43,6 @@ expand_one_var (tree var, unsigned char toplevel, unsigned
char really_expand)
}
/* We should thread the jump, through an intermediate block. */
/* { dg-final { scan-tree-dump-times Threaded 1 dom1} } */
-/* { dg-final { scan-tree-dump-times Registering jump thread .through joiner
block.: \\(.*\\); \\(.*\\); \\(.*\\); 1 dom1} } */
-
+/* { dg-final { scan-tree-dump-times Registering jump thread: \\(.*\\)
incoming edge; \\(.*\\) joiner; \\(.*\\) nocopy; 1 dom1} } */
/* { dg-final { cleanup-tree-dump dom1 } } */
diff --git a/gcc/tree-flow.h b/gcc/tree-flow.h
index 2f64abc..ee69179 100644
--- a/gcc/tree-flow.h
+++ b/gcc/tree-flow.h
@@ -641,10 +641,6 @@ bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum
machine_mode,
addr_space_t);
bool may_be_nonaddressable_p (tree expr);
-/* In tree-ssa-threadupdate.c. */
-extern bool thread_through_all_blocks (bool);
-extern void register_jump_thread (vecedge, bool);
-
/* In gimplify.c */
tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
tree force_gimple_operand (tree, gimple_seq *, bool, tree);
diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c
index f0cc0ee..81119c3 100644
--- a/gcc/tree-ssa-dom.c
+++ b/gcc/tree-ssa-dom.c
@@ -34,6 +34,7 @@ along with GCC; see the file COPYING3. If not see
#include domwalk.h
#include tree-pass.h
#include tree-ssa-propagate.h
+#include tree-ssa-threadupdate.h
#include langhooks.h
#include params.h
diff --git a/gcc/tree-ssa-threadedge.c b/gcc/tree-ssa-threadedge.c
index 2ca56342..467d982 100644
--- a/gcc/tree-ssa-threadedge.c
+++ b/gcc/tree-ssa-threadedge.c
@@ -32,6 +32,7 @@ along with GCC; see the file COPYING3. If not see
#include dumpfile.h
#include tree-ssa.h
#include tree-ssa-propagate.h
+#include tree-ssa-threadupdate.h
#include langhooks.h
#include params.h
@@ -753,7 +754,7 @@ thread_around_empty_blocks (edge taken_edge,
bool handle_dominating_asserts,
tree (*simplify) (gimple, gimple),
bitmap visited,
- vecedge *path)
+
