Hello.
Following patch marks -fstack-protect as Optimization flag.
That let a user to mark a function with #pragma GCC optimize
("-fno-stack-protector")
to disable the optimization for a function.
Patch survives regression tests and bootstraps on x86_64-linux-gnu.
Ready to install?
Thanks,
Martin
>From 4403f416d90e534502f755ab84c62ae2e75ae79a Mon Sep 17 00:00:00 2001
From: marxin <mli...@suse.cz>
Date: Fri, 24 Jun 2016 19:21:37 +0200
Subject: [PATCH] Mark -fstack-protect as optimization flag.
gcc/ChangeLog:
2016-06-27 Martin Liska <mli...@suse.cz>
PR middle-end/71585
* common.opt (flag_stack_protect): Mark the flag as optimization
flag.
* ipa-inline-transform.c (inline_call): Set flag_stack_protect
flag to caller of an inlined function.
gcc/testsuite/ChangeLog:
2016-06-27 Martin Liska <mli...@suse.cz>
* gcc.dg/pr71585.c: New test.
* gcc.dg/pr71585-2.c: New test.
---
gcc/common.opt | 8 ++++----
gcc/ipa-inline-transform.c | 15 +++++++++++++--
gcc/testsuite/gcc.dg/pr71585-2.c | 23 +++++++++++++++++++++++
gcc/testsuite/gcc.dg/pr71585.c | 23 +++++++++++++++++++++++
4 files changed, 63 insertions(+), 6 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/pr71585-2.c
create mode 100644 gcc/testsuite/gcc.dg/pr71585.c
diff --git a/gcc/common.opt b/gcc/common.opt
index 5d90385..a7c5125 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -2221,19 +2221,19 @@ Common RejectNegative Joined Var(common_deferred_options) Defer
-fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>.
fstack-protector
-Common Report Var(flag_stack_protect, 1) Init(-1)
+Common Report Var(flag_stack_protect, 1) Init(-1) Optimization
Use propolice as a stack protection method.
fstack-protector-all
-Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1)
+Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization
Use a stack protection method for every function.
fstack-protector-strong
-Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1)
+Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization
Use a smart stack protection method for certain functions.
fstack-protector-explicit
-Common Report RejectNegative Var(flag_stack_protect, 4)
+Common Report RejectNegative Var(flag_stack_protect, 4) Optimization
Use stack protection method only for functions with the stack_protect attribute.
fstack-usage
diff --git a/gcc/ipa-inline-transform.c b/gcc/ipa-inline-transform.c
index f6b7d41..f0e7528 100644
--- a/gcc/ipa-inline-transform.c
+++ b/gcc/ipa-inline-transform.c
@@ -342,10 +342,22 @@ inline_call (struct cgraph_edge *e, bool update_original,
if (dump_file)
fprintf (dump_file, "Dropping flag_strict_aliasing on %s:%i\n",
to->name (), to->order);
- build_optimization_node (&opts);
DECL_FUNCTION_SPECIFIC_OPTIMIZATION (to->decl)
= build_optimization_node (&opts);
}
+
+ if (opt_for_fn (callee->decl, flag_stack_protect)
+ && !opt_for_fn (to->decl, flag_stack_protect))
+ {
+ struct gcc_options opts = global_options;
+ cl_optimization_restore (&opts, opts_for_fn (to->decl));
+
+ opts.x_flag_stack_protect = opt_for_fn (callee->decl, flag_stack_protect);
+
+ DECL_FUNCTION_SPECIFIC_OPTIMIZATION (to->decl)
+ = build_optimization_node (&opts);
+ }
+
inline_summary *caller_info = inline_summaries->get (to);
inline_summary *callee_info = inline_summaries->get (callee);
if (!caller_info->fp_expressions && callee_info->fp_expressions)
@@ -402,7 +414,6 @@ inline_call (struct cgraph_edge *e, bool update_original,
if (dump_file)
fprintf (dump_file, "Copying FP flags from %s:%i to %s:%i\n",
callee->name (), callee->order, to->name (), to->order);
- build_optimization_node (&opts);
DECL_FUNCTION_SPECIFIC_OPTIMIZATION (to->decl)
= build_optimization_node (&opts);
}
diff --git a/gcc/testsuite/gcc.dg/pr71585-2.c b/gcc/testsuite/gcc.dg/pr71585-2.c
new file mode 100644
index 0000000..aad541f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr71585-2.c
@@ -0,0 +1,23 @@
+/* Test that stack protection is done on chosen functions. */
+
+/* { dg-do compile { target i?86-*-* x86_64-*-* rs6000-*-* s390x-*-* } } */
+/* { dg-options "-O2 -fstack-protector-all" } */
+
+/* This test checks the presence of __stack_chk_fail function in assembler.
+ * Compiler generates _stack_chk_fail_local (wrapper) calls instead for PIC.
+ */
+/* { dg-require-effective-target nonpic } */
+
+static int foo()
+{
+ return 0;
+}
+
+#pragma GCC push_options
+#pragma GCC optimize ("-fno-stack-protector")
+
+int main() { foo (); }
+
+#pragma GCC pop_options
+
+/* { dg-final { scan-assembler-times "stack_chk_fail" 1 } } */
diff --git a/gcc/testsuite/gcc.dg/pr71585.c b/gcc/testsuite/gcc.dg/pr71585.c
new file mode 100644
index 0000000..444aaa1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr71585.c
@@ -0,0 +1,23 @@
+/* Test that stack protection is done on chosen functions. */
+
+/* { dg-do compile { target i?86-*-* x86_64-*-* rs6000-*-* s390x-*-* } } */
+/* { dg-options "-O2 -fstack-protector-all" } */
+
+/* This test checks the presence of __stack_chk_fail function in assembler.
+ * Compiler generates _stack_chk_fail_local (wrapper) calls instead for PIC.
+ */
+/* { dg-require-effective-target nonpic } */
+
+#pragma GCC push_options
+
+#pragma GCC optimize ("-fno-stack-protector")
+__attribute__((constructor)) void foo()
+{
+ asm ("");
+}
+
+#pragma GCC pop_options
+
+int main() { return 0; }
+
+/* { dg-final { scan-assembler-times "stack_chk_fail" 1 } } */
--
2.8.4
