Improve live-in calculation for splitted block

  gcc/
    * shrink-wrap.c (move_insn_for_shrink_wrap): Initialize the live-in of new
    created BB as the intersection of live-in from "old_dest" and live-out from
    "bb".

  gcc/testsuite/
    * gcc.target/i386/shrink_wrap_1.c: New test.

From-SVN: r215611

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3bf52a6801c9a675bfe64b4b2dee192251391207..c3533ef2c15153c4296892eef38bc264af71961e 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2014-09-25  Jiong Wang  <jiong.wang@arm.com>
+
+       * shrink-wrap.c (move_insn_for_shrink_wrap): Initialize the live-in of
+       new created BB as the intersection of live-in from "old_dest" and
+       live-out from "bb".
+
 2014-09-25  Felix Yang  <felix.yang@huawei.com>
 
        * lra.c (lra_set_insn_recog_data): Fix typo in comment.

diff --git a/gcc/shrink-wrap.c b/gcc/shrink-wrap.c
index af23f0288d74730e11351915df91bd61f88fbaff..bd4813c82ae42400b678b08da76f3fad994dddcf 100644 (file)
--- a/gcc/shrink-wrap.c
+++ b/gcc/shrink-wrap.c
@@ -250,16 +250,21 @@ move_insn_for_shrink_wrap (basic_block bb, rtx_insn *insn,
       if (!df_live)
        return false;
 
+      basic_block old_dest = live_edge->dest;
       next_block = split_edge (live_edge);
 
       /* We create a new basic block.  Call df_grow_bb_info to make sure
         all data structures are allocated.  */
       df_grow_bb_info (df_live);
-      bitmap_copy (df_get_live_in (next_block), df_get_live_out (bb));
+
+      bitmap_and (df_get_live_in (next_block), df_get_live_out (bb),
+                 df_get_live_in (old_dest));
       df_set_bb_dirty (next_block);
 
       /* We should not split more than once for a function.  */
-      gcc_assert (!(*split_p));
+      if (*split_p)
+       return false;
+
       *split_p = true;
     }
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index fe01c672772c0c4eded7c7dac14f983487a055dc..9c7c3c9169d7a497f0485a83782676560ea7eff0 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2014-09-25  Jiong Wang  <jiong.wang@arm.com>
+
+       * gcc.target/i386/shrink_wrap_1.c: New test.
+
 2014-09-25  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
 
        PR target/63335

diff --git a/gcc/testsuite/gcc.target/i386/shrink_wrap_1.c b/gcc/testsuite/gcc.target/i386/shrink_wrap_1.c
new file mode 100644 (file)
index 0000000..47f2468
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/shrink_wrap_1.c
@@ -0,0 +1,48 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-rtl-pro_and_epilogue" } */
+
+enum machine_mode
+{
+  FAKE_0,
+  FAKE_1,
+  FAKE_2,
+  FAKE_3,
+  FAKE_4,
+  FAKE_5,
+  NUM_MACHINE_MODES,
+};
+
+typedef int *rtx;
+typedef long unsigned int size_t;
+extern unsigned char mode_size[NUM_MACHINE_MODES];
+
+extern rtx c_readstr (const char *, enum machine_mode);
+extern rtx convert_to_mode (enum machine_mode, rtx, int);
+extern rtx expand_mult (enum machine_mode, rtx, rtx, rtx, int);
+extern rtx force_reg (enum machine_mode, rtx);
+extern void *memset (void *__s, int __c, size_t __n);
+
+rtx
+builtin_memset_gen_str (void *data, long offset __attribute__ ((__unused__)),
+                       enum machine_mode mode)
+{
+  rtx target, coeff;
+  size_t size;
+  char *p;
+
+  size = ((unsigned short) (__builtin_constant_p (mode)
+                           ? mode_size_inline (mode) : mode_size[mode]));
+  if (size == 1)
+    return (rtx) data;
+
+  p = ((char *) __builtin_alloca(sizeof (char) * (size)));
+  memset (p, 1, size);
+  coeff = c_readstr (p, mode);
+
+  target = convert_to_mode (mode, (rtx) data, 1);
+  target = expand_mult (mode, target, coeff, (rtx) 0, 1);
+  return force_reg (mode, target);
+}
+
+/* { dg-final { scan-rtl-dump "Performing shrink-wrapping" "pro_and_epilogue"  } } */
+/* { dg-final { cleanup-rtl-dump "pro_and_epilogue" } } */