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Re: [PATCH 2/5] x86: Add -mfunction-return=
On Sun, Jan 14, 2018 at 3:31 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Sun, Jan 14, 2018 at 2:48 AM, Jan Hubicka <hubicka@ucw.cz> wrote:
>>> Add -mfunction-return= option to convert function return to call and
>>> return thunks. The default is 'keep', which keeps function return
>>> unmodified. 'thunk' converts function return to call and return thunk.
>>> 'thunk-inline' converts function return to inlined call and return thunk.
>>> 'thunk-extern' converts function return to external call and return
>>> thunk provided in a separate object file. You can control this behavior
>>> for a specific function by using the function attribute function_return.
>>>
>>> Function return thunk is the same as memory thunk for -mindirect-branch=
>>> where the return address is at the top of the stack:
>>>
>>> __x86_return_thunk:
>>> call L2
>>> L1:
>>> pause
>>> jmp L1
>>> L2:
>>> lea 8(%rsp), %rsp|lea 4(%esp), %esp
>>> ret
>>>
>>> and function return becomes
>>>
>>> jmp __x86_return_thunk
>>>
>>> -mindirect-branch= tests are updated with -mfunction-return=keep to
>>> avoid false test failures when -mfunction-return=thunk is added to
>>> RUNTESTFLAGS for "make check".
>>>
>>> gcc/
>>>
>>> * config/i386/i386-protos.h (ix86_output_function_return): New.
>>> * config/i386/i386.c (ix86_set_indirect_branch_type): Also
>>> set function_return_type.
>>> (indirect_thunk_name): Add ret_p to indicate thunk for function
>>> return.
>>> (output_indirect_thunk_function): Pass false to
>>> indirect_thunk_name.
>>> (ix86_output_indirect_branch): Likewise.
>>> (output_indirect_thunk_function): Create alias for function
>>> return thunk if regno < 0.
>>> (ix86_output_function_return): New function.
>>> (ix86_handle_fndecl_attribute): Handle function_return.
>>> (ix86_attribute_table): Add function_return.
>>> * config/i386/i386.h (machine_function): Add
>>> function_return_type.
>>> * config/i386/i386.md (simple_return_internal): Use
>>> ix86_output_function_return.
>>> (simple_return_internal_long): Likewise.
>>> * config/i386/i386.opt (mfunction-return=): New option.
>>> (indirect_branch): Mention -mfunction-return=.
>>> * doc/extend.texi: Document function_return function attribute.
>>> * doc/invoke.texi: Document -mfunction-return= option.
>>
>> The implementation is reasonable, but I still do not quite understand
>> if we really need this change. Celarly killing every return is going
>> to have significant impact and it is apparently not used by Linux kernel.
>> What is the main motivation for it?
>>
>> Honza
>
> See:
>
> https://gcc.gnu.org/ml/gcc-patches/2018-01/msg00540.html
>
> I will check it in.
>
Here is the patch I am checking in.
--
H.J.
From 2f05046a78afb173f301298df0a9a44b6fb38969 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Sat, 6 Jan 2018 22:29:56 -0800
Subject: [PATCH 2/6] x86: Add -mfunction-return=
Add -mfunction-return= option to convert function return to call and
return thunks. The default is 'keep', which keeps function return
unmodified. 'thunk' converts function return to call and return thunk.
'thunk-inline' converts function return to inlined call and return thunk.
'thunk-extern' converts function return to external call and return
thunk provided in a separate object file. You can control this behavior
for a specific function by using the function attribute function_return.
Function return thunk is the same as memory thunk for -mindirect-branch=
where the return address is at the top of the stack:
__x86_return_thunk:
call L2
L1:
pause
lfence
jmp L1
L2:
lea 8(%rsp), %rsp|lea 4(%esp), %esp
ret
and function return becomes
jmp __x86_return_thunk
-mindirect-branch= tests are updated with -mfunction-return=keep to
avoid false test failures when -mfunction-return=thunk is added to
RUNTESTFLAGS for "make check".
gcc/
* config/i386/i386-protos.h (ix86_output_function_return): New.
* config/i386/i386.c (ix86_set_indirect_branch_type): Also
set function_return_type.
(indirect_thunk_name): Add ret_p to indicate thunk for function
return.
(output_indirect_thunk_function): Pass false to
indirect_thunk_name.
(ix86_output_indirect_branch): Likewise.
(output_indirect_thunk_function): Create alias for function
return thunk if regno < 0.
(ix86_output_function_return): New function.
(ix86_handle_fndecl_attribute): Handle function_return.
(ix86_attribute_table): Add function_return.
* config/i386/i386.h (machine_function): Add
function_return_type.
* config/i386/i386.md (simple_return_internal): Use
ix86_output_function_return.
(simple_return_internal_long): Likewise.
* config/i386/i386.opt (mfunction-return=): New option.
(indirect_branch): Mention -mfunction-return=.
* doc/extend.texi: Document function_return function attribute.
* doc/invoke.texi: Document -mfunction-return= option.
gcc/testsuite/
* gcc.target/i386/indirect-thunk-1.c (dg-options): Add
-mfunction-return=keep.
* gcc.target/i386/indirect-thunk-2.c: Likewise.
* gcc.target/i386/indirect-thunk-3.c: Likewise.
* gcc.target/i386/indirect-thunk-4.c: Likewise.
* gcc.target/i386/indirect-thunk-5.c: Likewise.
* gcc.target/i386/indirect-thunk-6.c: Likewise.
* gcc.target/i386/indirect-thunk-7.c: Likewise.
* gcc.target/i386/indirect-thunk-attr-1.c: Likewise.
* gcc.target/i386/indirect-thunk-attr-2.c: Likewise.
* gcc.target/i386/indirect-thunk-attr-3.c: Likewise.
* gcc.target/i386/indirect-thunk-attr-4.c: Likewise.
* gcc.target/i386/indirect-thunk-attr-5.c: Likewise.
* gcc.target/i386/indirect-thunk-attr-6.c: Likewise.
* gcc.target/i386/indirect-thunk-attr-7.c: Likewise.
* gcc.target/i386/indirect-thunk-attr-8.c: Likewise.
* gcc.target/i386/indirect-thunk-bnd-1.c: Likewise.
* gcc.target/i386/indirect-thunk-bnd-2.c: Likewise.
* gcc.target/i386/indirect-thunk-bnd-3.c: Likewise.
* gcc.target/i386/indirect-thunk-bnd-4.c: Likewise.
* gcc.target/i386/indirect-thunk-extern-1.c: Likewise.
* gcc.target/i386/indirect-thunk-extern-2.c: Likewise.
* gcc.target/i386/indirect-thunk-extern-3.c: Likewise.
* gcc.target/i386/indirect-thunk-extern-4.c: Likewise.
* gcc.target/i386/indirect-thunk-extern-5.c: Likewise.
* gcc.target/i386/indirect-thunk-extern-6.c: Likewise.
* gcc.target/i386/indirect-thunk-extern-7.c: Likewise.
* gcc.target/i386/indirect-thunk-inline-1.c: Likewise.
* gcc.target/i386/indirect-thunk-inline-2.c: Likewise.
* gcc.target/i386/indirect-thunk-inline-3.c: Likewise.
* gcc.target/i386/indirect-thunk-inline-4.c: Likewise.
* gcc.target/i386/indirect-thunk-inline-5.c: Likewise.
* gcc.target/i386/indirect-thunk-inline-6.c: Likewise.
* gcc.target/i386/indirect-thunk-inline-7.c: Likewise.
* gcc.target/i386/ret-thunk-1.c: New test.
* gcc.target/i386/ret-thunk-10.c: Likewise.
* gcc.target/i386/ret-thunk-11.c: Likewise.
* gcc.target/i386/ret-thunk-12.c: Likewise.
* gcc.target/i386/ret-thunk-13.c: Likewise.
* gcc.target/i386/ret-thunk-14.c: Likewise.
* gcc.target/i386/ret-thunk-15.c: Likewise.
* gcc.target/i386/ret-thunk-16.c: Likewise.
* gcc.target/i386/ret-thunk-2.c: Likewise.
* gcc.target/i386/ret-thunk-3.c: Likewise.
* gcc.target/i386/ret-thunk-4.c: Likewise.
* gcc.target/i386/ret-thunk-5.c: Likewise.
* gcc.target/i386/ret-thunk-6.c: Likewise.
* gcc.target/i386/ret-thunk-7.c: Likewise.
* gcc.target/i386/ret-thunk-8.c: Likewise.
* gcc.target/i386/ret-thunk-9.c: Likewise.
---
gcc/config/i386/i386-protos.h | 1 +
gcc/config/i386/i386.c | 151 +++++++++++++++++++--
gcc/config/i386/i386.h | 3 +
gcc/config/i386/i386.md | 9 +-
gcc/config/i386/i386.opt | 6 +-
gcc/doc/extend.texi | 9 ++
gcc/doc/invoke.texi | 13 +-
gcc/testsuite/gcc.target/i386/indirect-thunk-1.c | 2 +-
gcc/testsuite/gcc.target/i386/indirect-thunk-2.c | 2 +-
gcc/testsuite/gcc.target/i386/indirect-thunk-3.c | 2 +-
gcc/testsuite/gcc.target/i386/indirect-thunk-4.c | 2 +-
gcc/testsuite/gcc.target/i386/indirect-thunk-5.c | 2 +-
gcc/testsuite/gcc.target/i386/indirect-thunk-6.c | 2 +-
gcc/testsuite/gcc.target/i386/indirect-thunk-7.c | 2 +-
.../gcc.target/i386/indirect-thunk-attr-1.c | 2 +-
.../gcc.target/i386/indirect-thunk-attr-2.c | 2 +-
.../gcc.target/i386/indirect-thunk-attr-3.c | 2 +-
.../gcc.target/i386/indirect-thunk-attr-4.c | 2 +-
.../gcc.target/i386/indirect-thunk-attr-5.c | 2 +-
.../gcc.target/i386/indirect-thunk-attr-6.c | 2 +-
.../gcc.target/i386/indirect-thunk-attr-7.c | 2 +-
.../gcc.target/i386/indirect-thunk-attr-8.c | 2 +-
.../gcc.target/i386/indirect-thunk-bnd-1.c | 2 +-
.../gcc.target/i386/indirect-thunk-bnd-2.c | 2 +-
.../gcc.target/i386/indirect-thunk-bnd-3.c | 2 +-
.../gcc.target/i386/indirect-thunk-bnd-4.c | 2 +-
.../gcc.target/i386/indirect-thunk-extern-1.c | 2 +-
.../gcc.target/i386/indirect-thunk-extern-2.c | 2 +-
.../gcc.target/i386/indirect-thunk-extern-3.c | 2 +-
.../gcc.target/i386/indirect-thunk-extern-4.c | 2 +-
.../gcc.target/i386/indirect-thunk-extern-5.c | 2 +-
.../gcc.target/i386/indirect-thunk-extern-6.c | 2 +-
.../gcc.target/i386/indirect-thunk-extern-7.c | 2 +-
.../gcc.target/i386/indirect-thunk-inline-1.c | 2 +-
.../gcc.target/i386/indirect-thunk-inline-2.c | 2 +-
.../gcc.target/i386/indirect-thunk-inline-3.c | 2 +-
.../gcc.target/i386/indirect-thunk-inline-4.c | 2 +-
.../gcc.target/i386/indirect-thunk-inline-5.c | 2 +-
.../gcc.target/i386/indirect-thunk-inline-6.c | 2 +-
.../gcc.target/i386/indirect-thunk-inline-7.c | 2 +-
gcc/testsuite/gcc.target/i386/ret-thunk-1.c | 13 ++
gcc/testsuite/gcc.target/i386/ret-thunk-10.c | 23 ++++
gcc/testsuite/gcc.target/i386/ret-thunk-11.c | 23 ++++
gcc/testsuite/gcc.target/i386/ret-thunk-12.c | 22 +++
gcc/testsuite/gcc.target/i386/ret-thunk-13.c | 22 +++
gcc/testsuite/gcc.target/i386/ret-thunk-14.c | 22 +++
gcc/testsuite/gcc.target/i386/ret-thunk-15.c | 22 +++
gcc/testsuite/gcc.target/i386/ret-thunk-16.c | 18 +++
gcc/testsuite/gcc.target/i386/ret-thunk-2.c | 13 ++
gcc/testsuite/gcc.target/i386/ret-thunk-3.c | 12 ++
gcc/testsuite/gcc.target/i386/ret-thunk-4.c | 12 ++
gcc/testsuite/gcc.target/i386/ret-thunk-5.c | 15 ++
gcc/testsuite/gcc.target/i386/ret-thunk-6.c | 14 ++
gcc/testsuite/gcc.target/i386/ret-thunk-7.c | 13 ++
gcc/testsuite/gcc.target/i386/ret-thunk-8.c | 14 ++
gcc/testsuite/gcc.target/i386/ret-thunk-9.c | 25 ++++
56 files changed, 491 insertions(+), 50 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-1.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-10.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-11.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-12.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-13.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-14.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-15.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-16.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-2.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-3.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-4.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-5.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-6.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-7.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-8.c
create mode 100644 gcc/testsuite/gcc.target/i386/ret-thunk-9.c
diff --git a/gcc/config/i386/i386-protos.h b/gcc/config/i386/i386-protos.h
index bf11cc426f9..fb86f00b3a6 100644
--- a/gcc/config/i386/i386-protos.h
+++ b/gcc/config/i386/i386-protos.h
@@ -306,6 +306,7 @@ extern enum attr_cpu ix86_schedule;
extern const char * ix86_output_call_insn (rtx_insn *insn, rtx call_op);
extern const char * ix86_output_indirect_jmp (rtx call_op, bool ret_p);
+extern const char * ix86_output_function_return (bool long_p);
extern bool ix86_operands_ok_for_move_multiple (rtx *operands, bool load,
machine_mode mode);
extern int ix86_min_insn_size (rtx_insn *);
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 43524f28d29..98c789094a4 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -5837,6 +5837,31 @@ ix86_set_indirect_branch_type (tree fndecl)
else
cfun->machine->indirect_branch_type = ix86_indirect_branch;
}
+
+ if (cfun->machine->function_return_type == indirect_branch_unset)
+ {
+ tree attr = lookup_attribute ("function_return",
+ DECL_ATTRIBUTES (fndecl));
+ if (attr != NULL)
+ {
+ tree args = TREE_VALUE (attr);
+ if (args == NULL)
+ gcc_unreachable ();
+ tree cst = TREE_VALUE (args);
+ if (strcmp (TREE_STRING_POINTER (cst), "keep") == 0)
+ cfun->machine->function_return_type = indirect_branch_keep;
+ else if (strcmp (TREE_STRING_POINTER (cst), "thunk") == 0)
+ cfun->machine->function_return_type = indirect_branch_thunk;
+ else if (strcmp (TREE_STRING_POINTER (cst), "thunk-inline") == 0)
+ cfun->machine->function_return_type = indirect_branch_thunk_inline;
+ else if (strcmp (TREE_STRING_POINTER (cst), "thunk-extern") == 0)
+ cfun->machine->function_return_type = indirect_branch_thunk_extern;
+ else
+ gcc_unreachable ();
+ }
+ else
+ cfun->machine->function_return_type = ix86_function_return;
+ }
}
/* Establish appropriate back-end context for processing the function
@@ -10709,8 +10734,12 @@ static int indirect_thunks_bnd_used;
/* Fills in the label name that should be used for the indirect thunk. */
static void
-indirect_thunk_name (char name[32], int regno, bool need_bnd_p)
+indirect_thunk_name (char name[32], int regno, bool need_bnd_p,
+ bool ret_p)
{
+ if (regno >= 0 && ret_p)
+ gcc_unreachable ();
+
if (USE_HIDDEN_LINKONCE)
{
const char *bnd = need_bnd_p ? "_bnd" : "";
@@ -10725,7 +10754,10 @@ indirect_thunk_name (char name[32], int regno, bool need_bnd_p)
bnd, reg_prefix, reg_names[regno]);
}
else
- sprintf (name, "__x86_indirect_thunk%s", bnd);
+ {
+ const char *ret = ret_p ? "return" : "indirect";
+ sprintf (name, "__x86_%s_thunk%s", ret, bnd);
+ }
}
else
{
@@ -10738,10 +10770,20 @@ indirect_thunk_name (char name[32], int regno, bool need_bnd_p)
}
else
{
- if (need_bnd_p)
- ASM_GENERATE_INTERNAL_LABEL (name, "LITB", 0);
+ if (ret_p)
+ {
+ if (need_bnd_p)
+ ASM_GENERATE_INTERNAL_LABEL (name, "LRTB", 0);
+ else
+ ASM_GENERATE_INTERNAL_LABEL (name, "LRT", 0);
+ }
else
- ASM_GENERATE_INTERNAL_LABEL (name, "LIT", 0);
+ {
+ if (need_bnd_p)
+ ASM_GENERATE_INTERNAL_LABEL (name, "LITB", 0);
+ else
+ ASM_GENERATE_INTERNAL_LABEL (name, "LIT", 0);
+ }
}
}
}
@@ -10836,7 +10878,7 @@ output_indirect_thunk_function (bool need_bnd_p, int regno)
tree decl;
/* Create __x86_indirect_thunk/__x86_indirect_thunk_bnd. */
- indirect_thunk_name (name, regno, need_bnd_p);
+ indirect_thunk_name (name, regno, need_bnd_p, false);
decl = build_decl (BUILTINS_LOCATION, FUNCTION_DECL,
get_identifier (name),
build_function_type_list (void_type_node, NULL_TREE));
@@ -10879,6 +10921,35 @@ output_indirect_thunk_function (bool need_bnd_p, int regno)
ASM_OUTPUT_LABEL (asm_out_file, name);
}
+ if (regno < 0)
+ {
+ /* Create alias for __x86.return_thunk/__x86.return_thunk_bnd. */
+ char alias[32];
+
+ indirect_thunk_name (alias, regno, need_bnd_p, true);
+ ASM_OUTPUT_DEF (asm_out_file, alias, name);
+#if TARGET_MACHO
+ if (TARGET_MACHO)
+ {
+ fputs ("\t.weak_definition\t", asm_out_file);
+ assemble_name (asm_out_file, alias);
+ fputs ("\n\t.private_extern\t", asm_out_file);
+ assemble_name (asm_out_file, alias);
+ putc ('\n', asm_out_file);
+ }
+#else
+ if (USE_HIDDEN_LINKONCE)
+ {
+ fputs ("\t.globl\t", asm_out_file);
+ assemble_name (asm_out_file, alias);
+ putc ('\n', asm_out_file);
+ fputs ("\t.hidden\t", asm_out_file);
+ assemble_name (asm_out_file, alias);
+ putc ('\n', asm_out_file);
+ }
+#endif
+ }
+
DECL_INITIAL (decl) = make_node (BLOCK);
current_function_decl = decl;
allocate_struct_function (decl, false);
@@ -28464,7 +28535,7 @@ ix86_output_indirect_branch_via_reg (rtx call_op, bool sibcall_p)
else
indirect_thunks_used |= 1 << i;
}
- indirect_thunk_name (thunk_name_buf, regno, need_bnd_p);
+ indirect_thunk_name (thunk_name_buf, regno, need_bnd_p, false);
thunk_name = thunk_name_buf;
}
else
@@ -28573,7 +28644,7 @@ ix86_output_indirect_branch_via_push (rtx call_op, const char *xasm,
else
indirect_thunk_needed = true;
}
- indirect_thunk_name (thunk_name_buf, regno, need_bnd_p);
+ indirect_thunk_name (thunk_name_buf, regno, need_bnd_p, false);
thunk_name = thunk_name_buf;
}
else
@@ -28708,6 +28779,46 @@ ix86_output_indirect_jmp (rtx call_op, bool ret_p)
return "%!jmp\t%A0";
}
+/* Output function return. CALL_OP is the jump target. Add a REP
+ prefix to RET if LONG_P is true and function return is kept. */
+
+const char *
+ix86_output_function_return (bool long_p)
+{
+ if (cfun->machine->function_return_type != indirect_branch_keep)
+ {
+ char thunk_name[32];
+ bool need_bnd_p = ix86_bnd_prefixed_insn_p (current_output_insn);
+
+ if (cfun->machine->function_return_type
+ != indirect_branch_thunk_inline)
+ {
+ bool need_thunk = (cfun->machine->function_return_type
+ == indirect_branch_thunk);
+ indirect_thunk_name (thunk_name, -1, need_bnd_p, true);
+ if (need_bnd_p)
+ {
+ indirect_thunk_bnd_needed |= need_thunk;
+ fprintf (asm_out_file, "\tbnd jmp\t%s\n", thunk_name);
+ }
+ else
+ {
+ indirect_thunk_needed |= need_thunk;
+ fprintf (asm_out_file, "\tjmp\t%s\n", thunk_name);
+ }
+ }
+ else
+ output_indirect_thunk (need_bnd_p, -1);
+
+ return "";
+ }
+
+ if (!long_p || ix86_bnd_prefixed_insn_p (current_output_insn))
+ return "%!ret";
+
+ return "rep%; ret";
+}
+
/* Output the assembly for a call instruction. */
const char *
@@ -41018,6 +41129,28 @@ ix86_handle_fndecl_attribute (tree *node, tree name, tree args, int,
}
}
+ if (is_attribute_p ("function_return", name))
+ {
+ tree cst = TREE_VALUE (args);
+ if (TREE_CODE (cst) != STRING_CST)
+ {
+ warning (OPT_Wattributes,
+ "%qE attribute requires a string constant argument",
+ name);
+ *no_add_attrs = true;
+ }
+ else if (strcmp (TREE_STRING_POINTER (cst), "keep") != 0
+ && strcmp (TREE_STRING_POINTER (cst), "thunk") != 0
+ && strcmp (TREE_STRING_POINTER (cst), "thunk-inline") != 0
+ && strcmp (TREE_STRING_POINTER (cst), "thunk-extern") != 0)
+ {
+ warning (OPT_Wattributes,
+ "argument to %qE attribute is not "
+ "(keep|thunk|thunk-inline|thunk-extern)", name);
+ *no_add_attrs = true;
+ }
+ }
+
return NULL_TREE;
}
@@ -45466,6 +45599,8 @@ static const struct attribute_spec ix86_attribute_table[] =
ix86_handle_fndecl_attribute, NULL },
{ "indirect_branch", 1, 1, true, false, false, false,
ix86_handle_fndecl_attribute, NULL },
+ { "function_return", 1, 1, true, false, false, false,
+ ix86_handle_fndecl_attribute, NULL },
/* End element. */
{ NULL, 0, 0, false, false, false, false, NULL, NULL }
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 3b939086112..bc4bc9a7a48 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -2577,6 +2577,9 @@ struct GTY(()) machine_function {
"indirect_jump" or "tablejump". */
BOOL_BITFIELD has_local_indirect_jump : 1;
+ /* How to generate function return. */
+ ENUM_BITFIELD(indirect_branch) function_return_type : 3;
+
/* If true, the current function is a function specified with
the "interrupt" or "no_caller_saved_registers" attribute. */
BOOL_BITFIELD no_caller_saved_registers : 1;
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 1ba144da87e..7e21c486d19 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -13058,7 +13058,7 @@
(define_insn "simple_return_internal"
[(simple_return)]
"reload_completed"
- "%!ret"
+ "* return ix86_output_function_return (false);"
[(set_attr "length" "1")
(set_attr "atom_unit" "jeu")
(set_attr "length_immediate" "0")
@@ -13080,12 +13080,7 @@
[(simple_return)
(unspec [(const_int 0)] UNSPEC_REP)]
"reload_completed"
-{
- if (ix86_bnd_prefixed_insn_p (insn))
- return "%!ret";
-
- return "rep%; ret";
-}
+ "* return ix86_output_function_return (true);"
[(set_attr "length" "2")
(set_attr "atom_unit" "jeu")
(set_attr "length_immediate" "0")
diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt
index 59e5cc8e7e4..7b17773592b 100644
--- a/gcc/config/i386/i386.opt
+++ b/gcc/config/i386/i386.opt
@@ -1026,9 +1026,13 @@ mindirect-branch=
Target Report RejectNegative Joined Enum(indirect_branch) Var(ix86_indirect_branch) Init(indirect_branch_keep)
Convert indirect call and jump to call and return thunks.
+mfunction-return=
+Target Report RejectNegative Joined Enum(indirect_branch) Var(ix86_function_return) Init(indirect_branch_keep)
+Convert function return to call and return thunk.
+
Enum
Name(indirect_branch) Type(enum indirect_branch)
-Known indirect branch choices (for use with the -mindirect-branch= option):
+Known indirect branch choices (for use with the -mindirect-branch=/-mfunction-return= options):
EnumValue
Enum(indirect_branch) String(keep) Value(indirect_branch_keep)
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index ddb6035be96..f120b2a1429 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -5764,6 +5764,15 @@ indirect call and jump to inlined call and return thunk.
@samp{thunk-extern} converts indirect call and jump to external call
and return thunk provided in a separate object file.
+@item function_return("@var{choice}")
+@cindex @code{function_return} function attribute, x86
+On x86 targets, the @code{function_return} attribute causes the compiler
+to convert function return with @var{choice}. @samp{keep} keeps function
+return unmodified. @samp{thunk} converts function return to call and
+return thunk. @samp{thunk-inline} converts function return to inlined
+call and return thunk. @samp{thunk-extern} converts function return to
+external call and return thunk provided in a separate object file.
+
@item nocf_check
@cindex @code{nocf_check} function attribute
The @code{nocf_check} attribute on a function is used to inform the
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 0d685c3576b..df945989fe8 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -1230,7 +1230,7 @@ See RS/6000 and PowerPC Options.
-mstack-protector-guard-offset=@var{offset} @gol
-mstack-protector-guard-symbol=@var{symbol} -mmitigate-rop @gol
-mgeneral-regs-only -mcall-ms2sysv-xlogues @gol
--mindirect-branch=@var{choice}}
+-mindirect-branch=@var{choice} -mfunction-return==@var{choice}}
@emph{x86 Windows Options}
@gccoptlist{-mconsole -mcygwin -mno-cygwin -mdll @gol
@@ -26850,6 +26850,17 @@ to external call and return thunk provided in a separate object file.
You can control this behavior for a specific function by using the
function attribute @code{indirect_branch}. @xref{Function Attributes}.
+@item -mfunction-return=@var{choice}
+@opindex -mfunction-return
+Convert function return with @var{choice}. The default is @samp{keep},
+which keeps function return unmodified. @samp{thunk} converts function
+return to call and return thunk. @samp{thunk-inline} converts function
+return to inlined call and return thunk. @samp{thunk-extern} converts
+function return to external call and return thunk provided in a separate
+object file. You can control this behavior for a specific function by
+using the function attribute @code{function_return}.
+@xref{Function Attributes}.
+
@end table
These @samp{-m} switches are supported in addition to the above
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-1.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-1.c
index d983e1c3e26..f076155c91a 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-1.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-2.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-2.c
index 58f09b42d8a..d7984f592fe 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-2.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-2.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-3.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-3.c
index f20d35c19b6..3257d0a2e16 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-3.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-3.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-4.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-4.c
index 0eff8fb658a..7cab2df6474 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-4.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-4.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-5.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-5.c
index a25b20dd808..b4836c38d6c 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-5.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-5.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target *-*-linux* } } */
-/* { dg-options "-O2 -fpic -fno-plt -mindirect-branch=thunk" } */
+/* { dg-options "-O2 -mfunction-return=keep -fpic -fno-plt -mindirect-branch=thunk" } */
extern void bar (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-6.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-6.c
index cff114a6c29..1f06bd1af74 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-6.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-6.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target *-*-linux* } } */
-/* { dg-options "-O2 -fpic -fno-plt -mindirect-branch=thunk" } */
+/* { dg-options "-O2 -mfunction-return=keep -fpic -fno-plt -mindirect-branch=thunk" } */
extern void bar (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-7.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-7.c
index afdb6007986..0b3fef86a20 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-7.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-7.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fno-pic" } */
void func0 (void);
void func1 (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-1.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-1.c
index d64d978b699..5f6cfc17b56 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-1.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-2.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-2.c
index 93067454d3d..b256160ec80 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-2.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-2.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-3.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-3.c
index 97744d65729..567c95051d6 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-3.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-3.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-4.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-4.c
index bfce3ea5cb2..3b662af7d5d 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-4.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-4.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-5.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-5.c
index 0833606046b..98785a38248 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-5.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-5.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-6.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-6.c
index 2eba0fbd9b2..a498a39e404 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-6.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-6.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-7.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-7.c
index f58427eae11..66f295d1eb6 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-7.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-7.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -fno-pic" } */
void func0 (void);
void func1 (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-8.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-8.c
index 564ed39547c..d730d31bda1 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-8.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-attr-8.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fno-pic" } */
void func0 (void);
void func1 (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-1.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-1.c
index 50fbee20a5a..aacb814d737 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-1.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target { ! x32 } } } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fcheck-pointer-bounds -mmpx -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fcheck-pointer-bounds -mmpx -fno-pic" } */
void (*dispatch) (char *);
char buf[10];
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-2.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-2.c
index 2976e67adce..7b44dda23df 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-2.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-2.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target { ! x32 } } } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fcheck-pointer-bounds -mmpx -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fcheck-pointer-bounds -mmpx -fno-pic" } */
void (*dispatch) (char *);
char buf[10];
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-3.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-3.c
index da4bc98ef23..70b4fb36eea 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-3.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-3.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target { *-*-linux* && { ! x32 } } } } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fcheck-pointer-bounds -mmpx -fpic -fno-plt" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fcheck-pointer-bounds -mmpx -fpic -fno-plt" } */
void bar (char *);
char buf[10];
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-4.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-4.c
index c64d12ef989..3baf03ee77c 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-4.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-bnd-4.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target { *-*-linux* && { ! x32 } } } } */
-/* { dg-options "-O2 -mindirect-branch=thunk -fcheck-pointer-bounds -mmpx -fpic -fno-plt" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fcheck-pointer-bounds -mmpx -fpic -fno-plt" } */
void bar (char *);
char buf[10];
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-1.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-1.c
index 49f27b49465..637fc3d3f4e 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-1.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-extern -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-extern -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-2.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-2.c
index a1e3eb6fc74..ff9efe03fe6 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-2.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-2.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-extern -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-extern -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-3.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-3.c
index 395634e7e5c..2686a5f2db4 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-3.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-3.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-extern -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-extern -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-4.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-4.c
index fd3f63379a1..f07f6b214ad 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-4.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-4.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-extern -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-extern -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-5.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-5.c
index ba2f92b6f34..21740ac5b7f 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-5.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-5.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target *-*-linux* } } */
-/* { dg-options "-O2 -fpic -fno-plt -mindirect-branch=thunk-extern" } */
+/* { dg-options "-O2 -mfunction-return=keep -fpic -fno-plt -mindirect-branch=thunk-extern" } */
extern void bar (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-6.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-6.c
index 0c5a2d472c6..a77c1f470b8 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-6.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-6.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target *-*-linux* } } */
-/* { dg-options "-O2 -fpic -fno-plt -mindirect-branch=thunk-extern" } */
+/* { dg-options "-O2 -mfunction-return=keep -fpic -fno-plt -mindirect-branch=thunk-extern" } */
extern void bar (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-7.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-7.c
index 665252327aa..e64910fd4aa 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-7.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-extern-7.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-extern -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-extern -fno-pic" } */
void func0 (void);
void func1 (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-1.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-1.c
index 68c0ff713b3..365cf2ee226 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-1.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-inline -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-inline -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-2.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-2.c
index e2da1fcb683..72646a4960b 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-2.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-2.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-inline -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-inline -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-3.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-3.c
index 244fec708d6..f48945e3dfc 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-3.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-3.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-inline -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-inline -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-4.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-4.c
index 107ebe32f54..4b1d558fc4e 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-4.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-4.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-inline -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-inline -fno-pic" } */
typedef void (*dispatch_t)(long offset);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-5.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-5.c
index 17b04ef2229..0f687c3b027 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-5.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-5.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target *-*-linux* } } */
-/* { dg-options "-O2 -fpic -fno-plt -mindirect-branch=thunk-inline" } */
+/* { dg-options "-O2 -mfunction-return=keep -fpic -fno-plt -mindirect-branch=thunk-inline" } */
extern void bar (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-6.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-6.c
index d9eb11285aa..b27c6fc96a2 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-6.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-6.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target *-*-linux* } } */
-/* { dg-options "-O2 -fpic -fno-plt -mindirect-branch=thunk-inline" } */
+/* { dg-options "-O2 -mfunction-return=keep -fpic -fno-plt -mindirect-branch=thunk-inline" } */
extern void bar (void);
diff --git a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-7.c b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-7.c
index d02b1dcb1b9..2c496492eaa 100644
--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-7.c
+++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-7.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -mindirect-branch=thunk-inline -fno-pic" } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-inline -fno-pic" } */
void func0 (void);
void func1 (void);
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-1.c b/gcc/testsuite/gcc.target/i386/ret-thunk-1.c
new file mode 100644
index 00000000000..7223f67ba5e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-1.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=thunk" } */
+
+void
+foo (void)
+{
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler {\tpause} } } */
+/* { dg-final { scan-assembler {\tlfence} } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-10.c b/gcc/testsuite/gcc.target/i386/ret-thunk-10.c
new file mode 100644
index 00000000000..1630e2fa2b5
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-10.c
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=thunk-inline -mindirect-branch=thunk -fno-pic" } */
+
+extern void (*bar) (void);
+
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-times {\tpause} 2 } } */
+/* { dg-final { scan-assembler-times {\tlfence} 2 } } */
+/* { dg-final { scan-assembler "push(?:l|q)\[ \t\]*_?bar" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_indirect_thunk" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "__x86_indirect_thunk:" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*__x86_indirect_thunk_(r|e)ax" { target { x32 } } } } */
+/* { dg-final { scan-assembler "__x86_indirect_thunk_(r|e)ax:" { target { x32 } } } } */
+/* { dg-final { scan-assembler-not "pushq\[ \t\]%rax" { target x32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-11.c b/gcc/testsuite/gcc.target/i386/ret-thunk-11.c
new file mode 100644
index 00000000000..876159cf783
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-11.c
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=thunk-extern -mindirect-branch=thunk -fno-pic" } */
+
+extern void (*bar) (void);
+
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-times {\tpause} 1 } } */
+/* { dg-final { scan-assembler-times {\tlfence} 1 } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "push(?:l|q)\[ \t\]*_?bar" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_indirect_thunk" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "__x86_indirect_thunk:" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*__x86_indirect_thunk_(r|e)ax" { target { x32 } } } } */
+/* { dg-final { scan-assembler "__x86_indirect_thunk_(r|e)ax:" { target { x32 } } } } */
+/* { dg-final { scan-assembler-not "pushq\[ \t\]%rax" { target x32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-12.c b/gcc/testsuite/gcc.target/i386/ret-thunk-12.c
new file mode 100644
index 00000000000..01b0a02f80b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-12.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk -fno-pic" } */
+
+extern void (*bar) (void);
+
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-times {\tpause} 1 } } */
+/* { dg-final { scan-assembler-times {\tlfence} 1 } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_indirect_thunk" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "__x86_indirect_thunk:" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*__x86_indirect_thunk_(r|e)ax" { target { x32 } } } } */
+/* { dg-final { scan-assembler "__x86_indirect_thunk_(r|e)ax:" { target { x32 } } } } */
+/* { dg-final { scan-assembler-not "pushq\[ \t\]%rax" { target x32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-13.c b/gcc/testsuite/gcc.target/i386/ret-thunk-13.c
new file mode 100644
index 00000000000..e028c2b6a99
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-13.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-inline -fno-pic" } */
+
+extern void (*bar) (void);
+extern int foo (void) __attribute__ ((function_return("thunk")));
+
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-times {\tpause} 2 } } */
+/* { dg-final { scan-assembler-times {\tlfence} 2 } } */
+/* { dg-final { scan-assembler "push(?:l|q)\[ \t\]*_?bar" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler-times "jmp\[ \t\]*\.LIND" 3 } } */
+/* { dg-final { scan-assembler-times "call\[ \t\]*\.LIND" 3 } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*__x86_indirect_thunk" } } */
+/* { dg-final { scan-assembler-not "call\[ \t\]*__x86_indirect_thunk_(r|e)ax" { target { x32 } } } } */
+/* { dg-final { scan-assembler-not "pushq\[ \t\]%rax" { target x32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-14.c b/gcc/testsuite/gcc.target/i386/ret-thunk-14.c
new file mode 100644
index 00000000000..c14ee3ae4c0
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-14.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=thunk-extern -fno-pic" } */
+
+extern void (*bar) (void);
+
+__attribute__ ((function_return("thunk-inline")))
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler-times {\tpause} 1 } } */
+/* { dg-final { scan-assembler-times {\tlfence} 1 } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "push(?:l|q)\[ \t\]*_?bar" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_indirect_thunk" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*__x86_indirect_thunk_(r|e)ax" { target { x32 } } } } */
+/* { dg-final { scan-assembler-not "pushq\[ \t\]%rax" { target x32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-15.c b/gcc/testsuite/gcc.target/i386/ret-thunk-15.c
new file mode 100644
index 00000000000..2f21e138ec2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-15.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=keep -mindirect-branch=keep -fno-pic" } */
+
+extern void (*bar) (void);
+
+__attribute__ ((function_return("thunk-extern"), indirect_branch("thunk")))
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler-times {\tpause} 1 } } */
+/* { dg-final { scan-assembler-times {\tlfence} 1 } } */
+/* { dg-final { scan-assembler "push(?:l|q)\[ \t\]*_?bar" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_indirect_thunk" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*__x86_indirect_thunk_(r|e)ax" { target x32 } } } */
+/* { dg-final { scan-assembler-not "pushq\[ \t\]%rax" { target x32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-16.c b/gcc/testsuite/gcc.target/i386/ret-thunk-16.c
new file mode 100644
index 00000000000..a16cad16aaa
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-16.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=thunk-inline -mindirect-branch=thunk-extern -fno-pic" } */
+
+extern void (*bar) (void);
+
+__attribute__ ((function_return("keep"), indirect_branch("keep")))
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "__x86_indirect_thunk" } } */
+/* { dg-final { scan-assembler-not "__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-not {\t(lfence|pause)} } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler-not "call\[ \t\]*\.LIND" } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-2.c b/gcc/testsuite/gcc.target/i386/ret-thunk-2.c
new file mode 100644
index 00000000000..c6659e3ad09
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-2.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=thunk-inline" } */
+
+void
+foo (void)
+{
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler {\tpause} } } */
+/* { dg-final { scan-assembler {\tlfence} } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*__x86_return_thunk" } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-3.c b/gcc/testsuite/gcc.target/i386/ret-thunk-3.c
new file mode 100644
index 00000000000..0f7f388f459
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-3.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=thunk-extern" } */
+
+void
+foo (void)
+{
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-not {\t(lfence|pause)} } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler-not "call\[ \t\]*\.LIND" } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-4.c b/gcc/testsuite/gcc.target/i386/ret-thunk-4.c
new file mode 100644
index 00000000000..9ae37e835a0
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-4.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=keep" } */
+
+void
+foo (void)
+{
+}
+
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-not {\t(lfence|pause)} } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler-not "call\[ \t\]*\.LIND" } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-5.c b/gcc/testsuite/gcc.target/i386/ret-thunk-5.c
new file mode 100644
index 00000000000..4bd0d2a27bc
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-5.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=keep" } */
+
+extern void foo (void) __attribute__ ((function_return("thunk")));
+
+void
+foo (void)
+{
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler {\tpause} } } */
+/* { dg-final { scan-assembler {\tlfence} } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-6.c b/gcc/testsuite/gcc.target/i386/ret-thunk-6.c
new file mode 100644
index 00000000000..053841f6f7d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-6.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=keep" } */
+
+__attribute__ ((function_return("thunk-inline")))
+void
+foo (void)
+{
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler {\tpause} } } */
+/* { dg-final { scan-assembler {\tlfence} } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*__x86_return_thunk" } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-7.c b/gcc/testsuite/gcc.target/i386/ret-thunk-7.c
new file mode 100644
index 00000000000..262e6780112
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-7.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=keep" } */
+
+__attribute__ ((function_return("thunk-extern")))
+void
+foo (void)
+{
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-not {\t(lfence|pause)} } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler-not "call\[ \t\]*\.LIND" } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-8.c b/gcc/testsuite/gcc.target/i386/ret-thunk-8.c
new file mode 100644
index 00000000000..c1658e96673
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-8.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=thunk-inline" } */
+
+extern void foo (void) __attribute__ ((function_return("keep")));
+
+void
+foo (void)
+{
+}
+
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-not {\t(lfence|pause)} } } */
+/* { dg-final { scan-assembler-not "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler-not "call\[ \t\]*\.LIND" } } */
diff --git a/gcc/testsuite/gcc.target/i386/ret-thunk-9.c b/gcc/testsuite/gcc.target/i386/ret-thunk-9.c
new file mode 100644
index 00000000000..f6ccad98da7
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/ret-thunk-9.c
@@ -0,0 +1,25 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mfunction-return=thunk -mindirect-branch=thunk -fno-pic" } */
+
+extern void (*bar) (void);
+
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_return_thunk" } } */
+/* { dg-final { scan-assembler-not "__x86_return_thunk:" } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "call\[ \t\]*\.LIND" } } */
+/* { dg-final { scan-assembler "__x86_indirect_thunk:" } } */
+/* { dg-final { scan-assembler-times {\tpause} 1 { target { ! x32 } } } } */
+/* { dg-final { scan-assembler-times {\tlfence} 1 { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "push(?:l|q)\[ \t\]*_?bar" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler "jmp\[ \t\]*__x86_indirect_thunk" { target { ! x32 } } } } */
+/* { dg-final { scan-assembler-times {\tpause} 2 { target { x32 } } } } */
+/* { dg-final { scan-assembler-times {\tlfence} 2 { target { x32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*__x86_indirect_thunk_(r|e)ax" { target { x32 } } } } */
+/* { dg-final { scan-assembler-not "pushq\[ \t\]%rax" { target x32 } } } */
--
2.14.3