Hi,
This patch is to fix regression reported in PR60280 by removing forward loop
headers/latches in cfg cleanup if possible. Several tests are broken by
this change since cfg cleanup is shared by all optimizers. Some tests has
already been fixed by recent patches, I went through and fixed the others.
One case needs to be clarified is "gcc.dg/tree-prof/update-loopch.c". When
GCC removing a basic block, it checks profile information by calling
check_bb_profile after redirecting incoming edges of the bb. This certainly
results in warnings about invalid profile information and causes the case to
fail. I will send a patch to skip checking profile information for a
removing basic block in stage 1 if it sounds reasonable. For now I just
twisted the case itself.
Bootstrap and tested on x86_64 and arm_a15.
Is it OK?
2014-02-25 Bin Cheng <bin.ch...@arm.com>
PR target/60280
* tree-cfgcleanup.c (tree_forwarder_block_p): Protect loop
preheaders and latches only if requested. Fix latch if it
is removed.
* tree-ssa-dom.c (tree_ssa_dominator_optimize): Set
LOOPS_HAVE_PREHEADERS.
gcc/testsuite/ChangeLog
2014-02-25 Bin Cheng <bin.ch...@arm.com>
PR target/60280
* gnat.dg/renaming5.adb: Change to two expected gotos.
* gcc.dg/tree-ssa/pr21559.c: Change back to three expected
jump threads.
* gcc.dg/tree-prof/update-loopch.c: Check two "Invalid sum"
messages for removed basic block.
* gcc.dg/tree-ssa/ivopt_1.c: Fix unreliable scanning string.
* gcc.dg/tree-ssa/ivopt_2.c: Ditto.
* gcc.dg/tree-ssa/ivopt_3.c: Ditto.
* gcc.dg/tree-ssa/ivopt_4.c: Ditto.Index: gcc/tree-ssa-dom.c
===================================================================
--- gcc/tree-ssa-dom.c (revision 207938)
+++ gcc/tree-ssa-dom.c (working copy)
@@ -849,9 +849,15 @@ tree_ssa_dominator_optimize (void)
/* We need to know loop structures in order to avoid destroying them
in jump threading. Note that we still can e.g. thread through loop
headers to an exit edge, or through loop header to the loop body, assuming
- that we update the loop info. */
- loop_optimizer_init (LOOPS_HAVE_SIMPLE_LATCHES);
+ that we update the loop info.
+ TODO: We don't need to set LOOPS_HAVE_PREHEADERS generally, but due
+ to several overly conservative bail-outs in jump threading, case
+ gcc.dg/tree-ssa/pr21417.c can't be threaded if loop preheader is
+ missing. We should improve jump threading in future then
+ LOOPS_HAVE_PREHEADERS won't be needed here. */
+ loop_optimizer_init (LOOPS_HAVE_PREHEADERS | LOOPS_HAVE_SIMPLE_LATCHES);
+
/* Initialize the value-handle array. */
threadedge_initialize_values ();
Index: gcc/tree-cfgcleanup.c
===================================================================
--- gcc/tree-cfgcleanup.c (revision 207938)
+++ gcc/tree-cfgcleanup.c (working copy)
@@ -308,14 +308,24 @@ tree_forwarder_block_p (basic_block bb, bool phi_w
if (current_loops)
{
basic_block dest;
- /* Protect loop latches, headers and preheaders. */
+ /* Protect loop headers. */
if (bb->loop_father->header == bb)
return false;
+
dest = EDGE_SUCC (bb, 0)->dest;
+ /* Protect loop preheaders and latches if requested. */
+ if (dest->loop_father->header == dest)
+ {
+ if (loops_state_satisfies_p (LOOPS_HAVE_PREHEADERS)
+ && bb->loop_father->header != dest)
+ return false;
- if (dest->loop_father->header == dest)
- return false;
+ if (loops_state_satisfies_p (LOOPS_HAVE_SIMPLE_LATCHES)
+ && bb->loop_father->header == dest)
+ return false;
+ }
}
+
return true;
}
@@ -497,6 +507,9 @@ remove_forwarder_block (basic_block bb)
set_immediate_dominator (CDI_DOMINATORS, dest, dom);
}
+ if (current_loops && bb->loop_father->latch == bb)
+ bb->loop_father->latch = dest;
+
/* And kill the forwarder block. */
delete_basic_block (bb);
Index: gcc/testsuite/gnat.dg/renaming5.adb
===================================================================
--- gcc/testsuite/gnat.dg/renaming5.adb (revision 207938)
+++ gcc/testsuite/gnat.dg/renaming5.adb (working copy)
@@ -26,5 +26,5 @@ package body Renaming5 is
end Renaming5;
--- { dg-final { scan-tree-dump-times "goto" 3 "optimized" } }
+-- { dg-final { scan-tree-dump-times "goto" 2 "optimized" } }
-- { dg-final { cleanup-tree-dump "optimized" } }
Index: gcc/testsuite/gcc.dg/tree-ssa/ivopt_2.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/ivopt_2.c (revision 207938)
+++ gcc/testsuite/gcc.dg/tree-ssa/ivopt_2.c (working copy)
@@ -13,5 +13,5 @@ void foo (int i_width, TYPE dst, TYPE src1, TYPE s
}
}
-/* { dg-final { scan-tree-dump-times "PHI <ivtmp" 1 "ivopts"} } */
+/* { dg-final { scan-tree-dump-times "PHI <.*ivtmp" 1 "ivopts"} } */
/* { dg-final { cleanup-tree-dump "ivopts" } } */
Index: gcc/testsuite/gcc.dg/tree-ssa/pr21559.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/pr21559.c (revision 207938)
+++ gcc/testsuite/gcc.dg/tree-ssa/pr21559.c (working copy)
@@ -37,7 +37,7 @@ void foo (void)
/* Second, we should thread the edge out of the loop via the break
statement. We also realize that the final bytes == 0 test is useless,
and thread over it. */
-/* { dg-final { scan-tree-dump-times "Threaded jump" 2 "vrp1" } } */
+/* { dg-final { scan-tree-dump-times "Threaded jump" 3 "vrp1" } } */
/* { dg-final { cleanup-tree-dump "vrp1" } } */
Index: gcc/testsuite/gcc.dg/tree-ssa/ivopt_4.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/ivopt_4.c (revision 207938)
+++ gcc/testsuite/gcc.dg/tree-ssa/ivopt_4.c (working copy)
@@ -15,5 +15,5 @@ void foo (int i_width, TYPE dst, TYPE src1, TYPE s
}
}
-/* { dg-final { scan-tree-dump-times "PHI <ivtmp" 1 "ivopts"} } */
+/* { dg-final { scan-tree-dump-times "PHI <.*ivtmp" 1 "ivopts"} } */
/* { dg-final { cleanup-tree-dump "ivopts" } } */
Index: gcc/testsuite/gcc.dg/tree-ssa/ivopt_1.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/ivopt_1.c (revision 207938)
+++ gcc/testsuite/gcc.dg/tree-ssa/ivopt_1.c (working copy)
@@ -14,5 +14,5 @@ void foo (int i_width, TYPE dst, TYPE src1, TYPE s
}
-/* { dg-final { scan-tree-dump-times "PHI <ivtmp" 1 "ivopts"} } */
+/* { dg-final { scan-tree-dump-times "PHI <.*ivtmp" 1 "ivopts"} } */
/* { dg-final { cleanup-tree-dump "ivopts" } } */
Index: gcc/testsuite/gcc.dg/tree-ssa/ivopt_3.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/ivopt_3.c (revision 207938)
+++ gcc/testsuite/gcc.dg/tree-ssa/ivopt_3.c (working copy)
@@ -14,7 +14,7 @@ void foo (int i_width, char* dst, char* src1, char
src1+=sizeof(TYPE);
src2+=sizeof(TYPE);
}
-}
+}
-/* { dg-final { scan-tree-dump-times "PHI <ivtmp" 1 "ivopts"} } */
+/* { dg-final { scan-tree-dump-times "PHI <.*ivtmp" 1 "ivopts"} } */
/* { dg-final { cleanup-tree-dump "ivopts" } } */
Index: gcc/testsuite/gcc.dg/tree-prof/update-loopch.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-prof/update-loopch.c (revision 207938)
+++ gcc/testsuite/gcc.dg/tree-prof/update-loopch.c (working copy)
@@ -16,6 +16,7 @@ main ()
edge. */
/* { dg-final-use { scan-ipa-dump "loop depth 1, count 33334" "profile"} } */
/* { dg-final-use { scan-tree-dump "loop depth 1, count 33332" "optimized"} }
*/
-/* { dg-final-use { scan-tree-dump-not "Invalid sum" "optimized"} } */
+/* { dg-final-use { scan-tree-dump-times "Removing basic block
\[^\r\n\]*\[\\r\\n\]+\[^\r\n\]*\[\\r\\n\]+Invalid sum
of\[^\r\n\]*\[\\r\\n\]+Invalid sum of" 1 "optimized"} } */
+/* { dg-final-use { scan-tree-dump-times "Invalid sum of" 2 "optimized"} } */
/* { dg-final-use { cleanup-ipa-dump "profile" } } */
/* { dg-final-use { cleanup-tree-dump "optimized" } } */
