[gcc(refs/users/aoliva/heads/testme)] enable control flow redundancy hardening unconditionally

[Alexandre Oliva <aoliva@gcc.gnu.org>]

https://gcc.gnu.org/g:7eeca96058d2affd9c959fd55ab01ff803f9b880

commit 7eeca96058d2affd9c959fd55ab01ff803f9b880
Author: Alexandre Oliva <oliva@adacore.com>
Date:   Mon Jan 31 16:00:46 2022 -0300

    enable control flow redundancy hardening unconditionally

Diff:
---
 gcc/common.opt                    | 2 +-
 gcc/gimple-harden-control-flow.cc | 6 ++++++
 gcc/params.opt                    | 2 +-
 libgcc/Makefile.in                | 2 ++
 4 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/gcc/common.opt b/gcc/common.opt
index cb0ce11eee1..a353165ba15 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -1771,7 +1771,7 @@ Common Var(flag_harden_conditional_branches) Optimization
 Harden conditional branches by checking reversed conditions.
 
 fharden-control-flow-redundancy
-Common Var(flag_harden_control_flow_redundancy) Optimization
+Common Var(flag_harden_control_flow_redundancy) Init(-1) Optimization
 Harden control flow by recording and checking execution paths.
 
 ; Nonzero means ignore `#ident' directives.  0 means handle them.
diff --git a/gcc/gimple-harden-control-flow.cc b/gcc/gimple-harden-control-flow.cc
index f3538c895fb..72258f65360 100644
--- a/gcc/gimple-harden-control-flow.cc
+++ b/gcc/gimple-harden-control-flow.cc
@@ -97,6 +97,8 @@ public:
        call and restore it if it returns again.  */
     if (fun->calls_setjmp)
       {
+	if (flag_harden_control_flow_redundancy < 0)
+	  return false;
 	warning_at (DECL_SOURCE_LOCATION (fun->decl), 0,
 		    "%qD calls %<setjmp%> or similar,"
 		    " %<-fharden-control-flow-redundancy%> is not supported",
@@ -110,6 +112,8 @@ public:
        enough to make it worthwhile.  */
     if (fun->has_nonlocal_label)
       {
+	if (flag_harden_control_flow_redundancy < 0)
+	  return false;
 	warning_at (DECL_SOURCE_LOCATION (fun->decl), 0,
 		    "%qD receives nonlocal gotos,"
 		    " %<-fharden-control-flow-redundancy%> is not supported",
@@ -120,6 +124,8 @@ public:
     if (param_hardcfr_max_blocks > 0
 	&& n_basic_blocks_for_fn (fun) - 2 > param_hardcfr_max_blocks)
       {
+	if (flag_harden_control_flow_redundancy < 0)
+	  return false;
 	warning_at (DECL_SOURCE_LOCATION (fun->decl), 0,
 		    "%qD has more than %u blocks, the requested"
 		    " maximum for %<-fharden-control-flow-redundancy%>",
diff --git a/gcc/params.opt b/gcc/params.opt
index b5dd3a92d06..b8cd9f7a4ed 100644
--- a/gcc/params.opt
+++ b/gcc/params.opt
@@ -202,7 +202,7 @@ Common Joined UInteger Var(param_graphite_max_nb_scop_params) Init(10) Param Opt
 Maximum number of parameters in a SCoP.
 
 -param=hardcfr-max-blocks=
-Common Joined UInteger Var(param_hardcfr_max_blocks) Init(0) Param Optimization
+Common Joined UInteger Var(param_hardcfr_max_blocks) Init(32) Param Optimization
 Maximum number of blocks for -fharden-control-flow-redundancy.
 
 -param=hardcfr-max-inline-blocks=
diff --git a/libgcc/Makefile.in b/libgcc/Makefile.in
index ff76d29f25b..ce90960de04 100644
--- a/libgcc/Makefile.in
+++ b/libgcc/Makefile.in
@@ -429,6 +429,8 @@ iterator = $(patsubst %,$(srcdir)/static-object.mk,$(iter-items))
 endif
 
 LIB2ADD += enable-execute-stack.c
+
+# Control Flow Redundancy hardening out-of-line checker.
 LIB2ADD += $(srcdir)/hardcfr.c
 
 # While emutls.c has nothing to do with EH, it is in LIB2ADDEH*