Radically simplify emission of balanced tree for switch statements.

2018-05-18  Martin Liska  <mliska@suse.cz>

	* passes.def: Add pass_lower_switch and pass_lower_switch_O0.
	* tree-pass.h (make_pass_lower_switch_O0): New function.
	* tree-switch-conversion.c (node_has_low_bound): Remove.
	(node_has_high_bound): Likewise.
	(node_is_bounded): Likewise.
	(class pass_lower_switch): Make it a template type and create
	two instances.
	(pass_lower_switch::execute): Add template argument.
	(make_pass_lower_switch): New function.
	(make_pass_lower_switch_O0): New function.
	(do_jump_if_equal): Remove.
	(emit_case_nodes): Simplify to just handle all 3 cases and leave
	all the hard work to tree optimization passes.
2018-05-18  Martin Liska  <mliska@suse.cz>

	* gcc.dg/tree-ssa/vrp104.c: Adjust dump file that is scanned.
	* gcc.dg/tree-prof/update-loopch.c: Likewise.

From-SVN: r260350

gcc/ChangeLog

 2018-05-18  Martin Liska  <mliska@suse.cz>
 
+	* passes.def: Add pass_lower_switch and pass_lower_switch_O0.
+	* tree-pass.h (make_pass_lower_switch_O0): New function.
+	* tree-switch-conversion.c (node_has_low_bound): Remove.
+	(node_has_high_bound): Likewise.
+	(node_is_bounded): Likewise.
+	(class pass_lower_switch): Make it a template type and create
+	two instances.
+	(pass_lower_switch::execute): Add template argument.
+	(make_pass_lower_switch): New function.
+	(make_pass_lower_switch_O0): New function.
+	(do_jump_if_equal): Remove.
+	(emit_case_nodes): Simplify to just handle all 3 cases and leave
+	all the hard work to tree optimization passes.
+
+2018-05-18  Martin Liska  <mliska@suse.cz>
+
 	* dbgcnt.c (limit_low): Renamed from limit.
 	(limit_high): New variable.
 	(dbg_cnt_is_enabled): Check for upper limit.

gcc/passes.def

@@ -317,6 +317,7 @@ along with GCC; see the file COPYING3.  If not see
       POP_INSERT_PASSES ()
       NEXT_PASS (pass_simduid_cleanup);
       NEXT_PASS (pass_lower_vector_ssa);
+      NEXT_PASS (pass_lower_switch);
       NEXT_PASS (pass_cse_reciprocals);
       NEXT_PASS (pass_sprintf_length, true);
       NEXT_PASS (pass_reassoc, false /* insert_powi_p */);
@@ -362,6 +363,7 @@ along with GCC; see the file COPYING3.  If not see
       /* Lower remaining pieces of GIMPLE.  */
       NEXT_PASS (pass_lower_complex);
       NEXT_PASS (pass_lower_vector_ssa);
+      NEXT_PASS (pass_lower_switch);
       /* Perform simple scalar cleanup which is constant/copy propagation.  */
       NEXT_PASS (pass_ccp, true /* nonzero_p */);
       NEXT_PASS (pass_post_ipa_warn);
@@ -397,6 +399,7 @@ along with GCC; see the file COPYING3.  If not see
   NEXT_PASS (pass_lower_vaarg);
   NEXT_PASS (pass_lower_vector);
   NEXT_PASS (pass_lower_complex_O0);
+  NEXT_PASS (pass_lower_switch_O0);
   NEXT_PASS (pass_sancov_O0);
   NEXT_PASS (pass_lower_switch);
   NEXT_PASS (pass_asan_O0);

gcc/testsuite/ChangeLog

 2018-05-18  Martin Liska  <mliska@suse.cz>
 
+	* gcc.dg/tree-ssa/vrp104.c: Adjust dump file that is scanned.
+	* gcc.dg/tree-prof/update-loopch.c: Likewise.
+
+2018-05-18  Martin Liska  <mliska@suse.cz>
+
 	* gcc.dg/ipa/ipa-icf-39.c: New test.
 	* gcc.dg/pr68766.c: Adjust pruned output.
 

gcc/testsuite/gcc.dg/tree-prof/update-loopch.c

-/* { dg-options "-O2 -fdump-ipa-profile-blocks-details -fdump-tree-switchlower-blocks-details" } */
+/* { dg-options "-O2 -fdump-ipa-profile-blocks-details -fdump-tree-switchlower1-blocks-details" } */
 int max = 33333;
 int a[8];
 int

gcc/testsuite/gcc.dg/tree-ssa/vrp104.c

@@ -2,7 +2,7 @@
 /* { dg-options "-O2 -fdump-tree-switchlower" }  */
 /* We scan for 2 switches as the dump file reports a transformation,
    IL really contains just a single.  */
-/* { dg-final { scan-tree-dump-times "switch \\(i_" 2 "switchlower" } }  */
+/* { dg-final { scan-tree-dump-times "switch" 2 "switchlower1" } }  */
 
 void foo (void);
 void bar (void);

gcc/tree-pass.h

@@ -413,6 +413,7 @@ extern gimple_opt_pass *make_pass_strip_predict_hints (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_lower_complex_O0 (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_lower_complex (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_lower_switch (gcc::context *ctxt);
+extern gimple_opt_pass *make_pass_lower_switch_O0 (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_lower_vector (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_lower_vector_ssa (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_lower_omp (gcc::context *ctxt);