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[PATCH] Add __builtin_stack_top
- From: "H.J. Lu" <hjl dot tools at gmail dot com>
- To: Segher Boessenkool <segher at kernel dot crashing dot org>
- Cc: GCC Patches <gcc-patches at gcc dot gnu dot org>, Uros Bizjak <ubizjak at gmail dot com>
- Date: Tue, 4 Aug 2015 05:30:57 -0700
- Subject: [PATCH] Add __builtin_stack_top
- Authentication-results: sourceware.org; auth=none
On Wed, Jul 22, 2015 at 8:44 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Wed, Jul 22, 2015 at 6:59 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
>> On Wed, Jul 22, 2015 at 6:55 AM, Segher Boessenkool
>> <segher@kernel.crashing.org> wrote:
>>> On Wed, Jul 22, 2015 at 05:10:04AM -0700, H.J. Lu wrote:
>>>> I got a feedback, suggesting __builtin_stack_top, instead of
>>>> __builtin_ia32_stack_top. But I don't know if
>>>>
>>>> + /* After the prologue, stack top is at -WORD(AP) in the current
>>>> + frame. */
>>>> + emit_insn (gen_rtx_SET (target,
>>>> + plus_constant (Pmode, arg_pointer_rtx,
>>>> + -UNITS_PER_WORD)));
>>>>
>>>> is true for all backends. If it works on all backends, I can move
>>>> it to builtins.c.
>>>
>>> It doesn't afaik. But can't you define INITIAL_FRAME_ADDRESS_RTX?
>>>
>>>
>>> Segher
>>
>> Does INITIAL_FRAME_ADDRESS_RTX point to stack top? It certainly
>> can't be defined for x86. I will write a midld-end patch and leave to each
>> backend to enable it.
>
> Here is a patch. Any comments, feedbacks?
Where does this feature belong? Middle-end or x86 backend?
Here is the updated patch to implement it in middle-end. Any
comments?
Thanks.
> Thanks.
>
> --
> H.J.
> ---
> When __builtin_frame_address is used to retrieve the address of the
> function stack frame, the frame pointer is always kept, which wastes one
> register and 2 instructions. For x86-32, one less register means
> significant negative impact on performance. This patch adds a new
> builtin function, __builtin_stack_top. It returns the stack address
> when the function is called.
>
> This patch only enables __builtin_stack_top for x86 backend. Using
> __builtin_stack_top with other backends will lead to
>
> sorry, unimplemented: â__builtin_stack_topâ not supported on this target
>
> TARGET_STACK_TOP_RTX must be defined to enable __builtin_stack_top.
> default_stack_top_rtx may be extended to support more backends,
> including those with INITIAL_FRAME_ADDRESS_RTX.
>
> gcc/
>
> PR target/66960
> * builtin-types.def (BT_FN_PTR_VOID): New function type.
> * builtins.c (expand_builtin): Handle BUILT_IN_STACK_TOP.
> (is_simple_builtin): Likewise.
> * ipa-pure-const.c (special_builtin_state): Likewise.
> * builtins.def: Add BUILT_IN_STACK_TOP.
> * function.h (function): Add stack_top_taken.
> * target.def (stack_top_rtx): New target hook.
> * targhooks.c (default_stack_top_rtx): New.
> * targhooks.h (default_stack_top_rtx): Likewise.
> * config/i386/i386.c (ix86_expand_prologue): Sorry if DRAP is
> used and the stack address has been taken.
> (TARGET_STACK_TOP_RTX): New.
> * doc/extend.texi: Document __builtin_stack_top.
> * doc/tm.texi.in (TARGET_STACK_TOP_RTX): New.
> * doc/tm.texi: Regenerated.
>
> gcc/testsuite/
>
> PR target/66960
> * gcc.target/i386/pr66960-1.c: New test.
> * gcc.target/i386/pr66960-2.c: Likewise.
> * gcc.target/i386/pr66960-3.c: Likewise.
> * gcc.target/i386/pr66960-4.c: Likewise.
> * gcc.target/i386/pr66960-5.c: Likewise.
--
H.J.
From 267982f7c76cc6eece0dd7896555d27291f587ef Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Tue, 21 Jul 2015 14:32:09 -0700
Subject: [PATCH] Add __builtin_stack_top
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
When __builtin_frame_address is used to retrieve the address of the
function stack frame, the frame pointer register is required, which
wastes one register and 2 instructions. For x86-32, one less register
means significant negative impact on performance. This patch adds a
new builtin function, __builtin_stack_top. It returns the stack address
when the function is called.
This patch only enables __builtin_stack_top for x86 backend. Using
__builtin_stack_top with other backends will lead to
sorry, unimplemented: â__builtin_stack_topâ not supported on this target
TARGET_STACK_TOP_RTX must be defined to enable __builtin_stack_top.
default_stack_top_rtx may be extended to support more backends,
including those with INITIAL_FRAME_ADDRESS_RTX.
gcc/
PR target/66960
* builtin-types.def (BT_FN_PTR_VOID): New function type.
* builtins.c (expand_builtin): Handle BUILT_IN_STACK_TOP.
(is_simple_builtin): Likewise.
* ipa-pure-const.c (special_builtin_state): Likewise.
* builtins.def: Add BUILT_IN_STACK_TOP.
* function.h (function): Add stack_top_taken.
* target.def (stack_top_rtx): New target hook.
* targhooks.c (default_stack_top_rtx): New.
* targhooks.h (default_stack_top_rtx): Likewise.
* config/i386/i386.c (ix86_expand_prologue): Sorry if DRAP is
used and the stack address has been taken.
(TARGET_STACK_TOP_RTX): New.
* doc/extend.texi: Document __builtin_stack_top.
* doc/tm.texi.in (TARGET_STACK_TOP_RTX): New.
* doc/tm.texi: Regenerated.
gcc/testsuite/
PR target/66960
* gcc.target/i386/pr66960-1.c: New test.
* gcc.target/i386/pr66960-2.c: Likewise.
* gcc.target/i386/pr66960-3.c: Likewise.
* gcc.target/i386/pr66960-4.c: Likewise.
* gcc.target/i386/pr66960-5.c: Likewise.
---
gcc/builtin-types.def | 1 +
gcc/builtins.c | 11 +++++++++++
gcc/builtins.def | 1 +
gcc/config/i386/i386.c | 8 ++++++++
gcc/doc/extend.texi | 7 +++++++
gcc/doc/tm.texi | 5 +++++
gcc/doc/tm.texi.in | 2 ++
gcc/function.h | 3 +++
gcc/ipa-pure-const.c | 1 +
gcc/target.def | 7 +++++++
gcc/targhooks.c | 9 +++++++++
gcc/targhooks.h | 3 +++
gcc/testsuite/gcc.target/i386/pr66960-1.c | 33 +++++++++++++++++++++++++++++++
gcc/testsuite/gcc.target/i386/pr66960-2.c | 33 +++++++++++++++++++++++++++++++
gcc/testsuite/gcc.target/i386/pr66960-3.c | 17 ++++++++++++++++
gcc/testsuite/gcc.target/i386/pr66960-4.c | 21 ++++++++++++++++++++
gcc/testsuite/gcc.target/i386/pr66960-5.c | 21 ++++++++++++++++++++
17 files changed, 183 insertions(+)
create mode 100644 gcc/testsuite/gcc.target/i386/pr66960-1.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr66960-2.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr66960-3.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr66960-4.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr66960-5.c
diff --git a/gcc/builtin-types.def b/gcc/builtin-types.def
index 0e34531..2b6b5ab 100644
--- a/gcc/builtin-types.def
+++ b/gcc/builtin-types.def
@@ -177,6 +177,7 @@ DEF_FUNCTION_TYPE_1 (BT_FN_COMPLEX_LONGDOUBLE_LONGDOUBLE,
BT_COMPLEX_LONGDOUBLE, BT_LONGDOUBLE)
DEF_FUNCTION_TYPE_1 (BT_FN_PTR_UINT, BT_PTR, BT_UINT)
DEF_FUNCTION_TYPE_1 (BT_FN_PTR_SIZE, BT_PTR, BT_SIZE)
+DEF_FUNCTION_TYPE_1 (BT_FN_PTR_VOID, BT_PTR, BT_VOID)
DEF_FUNCTION_TYPE_1 (BT_FN_INT_INT, BT_INT, BT_INT)
DEF_FUNCTION_TYPE_1 (BT_FN_INT_UINT, BT_INT, BT_UINT)
DEF_FUNCTION_TYPE_1 (BT_FN_INT_LONG, BT_INT, BT_LONG)
diff --git a/gcc/builtins.c b/gcc/builtins.c
index eb7b7b2..b257baf 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -6210,6 +6210,16 @@ expand_builtin (tree exp, rtx target, rtx subtarget, machine_mode mode,
case BUILT_IN_CONSTANT_P:
return const0_rtx;
+ case BUILT_IN_STACK_TOP:
+ if (targetm.calls.stack_top_rtx)
+ {
+ cfun->stack_top_taken = true;
+ return targetm.calls.stack_top_rtx ();
+ }
+ else
+ sorry ("%<__builtin_stack_top%> not supported on this target");
+ break;
+
case BUILT_IN_FRAME_ADDRESS:
case BUILT_IN_RETURN_ADDRESS:
return expand_builtin_frame_address (fndecl, exp);
@@ -12399,6 +12409,7 @@ is_simple_builtin (tree decl)
case BUILT_IN_RETURN:
case BUILT_IN_AGGREGATE_INCOMING_ADDRESS:
case BUILT_IN_FRAME_ADDRESS:
+ case BUILT_IN_STACK_TOP:
case BUILT_IN_VA_END:
case BUILT_IN_STACK_SAVE:
case BUILT_IN_STACK_RESTORE:
diff --git a/gcc/builtins.def b/gcc/builtins.def
index 80e4a9c..62f0523 100644
--- a/gcc/builtins.def
+++ b/gcc/builtins.def
@@ -778,6 +778,7 @@ DEF_EXT_LIB_BUILTIN (BUILT_IN_FFSL, "ffsl", BT_FN_INT_LONG, ATTR_CONST_NOTHRO
DEF_EXT_LIB_BUILTIN (BUILT_IN_FFSLL, "ffsll", BT_FN_INT_LONGLONG, ATTR_CONST_NOTHROW_LEAF_LIST)
DEF_EXT_LIB_BUILTIN (BUILT_IN_FORK, "fork", BT_FN_PID, ATTR_NOTHROW_LIST)
DEF_GCC_BUILTIN (BUILT_IN_FRAME_ADDRESS, "frame_address", BT_FN_PTR_UINT, ATTR_NULL)
+DEF_GCC_BUILTIN (BUILT_IN_STACK_TOP, "stack_top", BT_FN_PTR_VOID, ATTR_NULL)
/* [trans-mem]: Adjust BUILT_IN_TM_FREE if BUILT_IN_FREE is changed. */
DEF_LIB_BUILTIN (BUILT_IN_FREE, "free", BT_FN_VOID_PTR, ATTR_NOTHROW_LEAF_LIST)
DEF_GCC_BUILTIN (BUILT_IN_FROB_RETURN_ADDR, "frob_return_addr", BT_FN_PTR_PTR, ATTR_NULL)
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 1b0cade..0c77363 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -11575,6 +11575,12 @@ ix86_expand_prologue (void)
{
int align_bytes = crtl->stack_alignment_needed / BITS_PER_UNIT;
+ /* Can't use DRAP if the stack address has been taken. */
+ if (cfun->stack_top_taken)
+ sorry ("%<__builtin_stack_top%> not supported with stack"
+ " realignment. This may be worked around by adding"
+ " -maccumulate-outgoing-args.");
+
/* Only need to push parameter pointer reg if it is caller saved. */
if (!call_used_regs[REGNO (crtl->drap_reg)])
{
@@ -52513,6 +52519,8 @@ ix86_operands_ok_for_move_multiple (rtx *operands, bool load,
#define TARGET_UPDATE_STACK_BOUNDARY ix86_update_stack_boundary
#undef TARGET_GET_DRAP_RTX
#define TARGET_GET_DRAP_RTX ix86_get_drap_rtx
+#undef TARGET_STACK_TOP_RTX
+#define TARGET_STACK_TOP_RTX default_stack_top_rtx
#undef TARGET_STRICT_ARGUMENT_NAMING
#define TARGET_STRICT_ARGUMENT_NAMING hook_bool_CUMULATIVE_ARGS_true
#undef TARGET_STATIC_CHAIN
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 2a47943..834b7f4 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -8841,6 +8841,13 @@ option is in effect. Such calls should only be made in debugging
situations.
@end deftypefn
+@deftypefn {Built-in Function} {void *} __builtin_stack_top (void)
+This function is similar to calling @code{__builtin_frame_address}
+with a value of @code{0}, but it returns the stack address when the
+function is called. Unlike @code{__builtin_frame_address}, the frame
+pointer register isn't required.
+@end deftypefn
+
@node Vector Extensions
@section Using Vector Instructions through Built-in Functions
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
index f95646c..e2cd480 100644
--- a/gcc/doc/tm.texi
+++ b/gcc/doc/tm.texi
@@ -11483,6 +11483,11 @@ argument list due to stack realignment. Return @code{NULL} if no DRAP
is needed.
@end deftypefn
+@deftypefn {Target Hook} rtx TARGET_STACK_TOP_RTX (void)
+This hook should return an rtx for the stack address when the function
+is called.
+@end deftypefn
+
@deftypefn {Target Hook} bool TARGET_ALLOCATE_STACK_SLOTS_FOR_ARGS (void)
When optimization is disabled, this hook indicates whether or not
arguments should be allocated to stack slots. Normally, GCC allocates
diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
index 2383fb9..9167069 100644
--- a/gcc/doc/tm.texi.in
+++ b/gcc/doc/tm.texi.in
@@ -8181,6 +8181,8 @@ and the associated definitions of those functions.
@hook TARGET_GET_DRAP_RTX
+@hook TARGET_STACK_TOP_RTX
+
@hook TARGET_ALLOCATE_STACK_SLOTS_FOR_ARGS
@hook TARGET_CONST_ANCHOR
diff --git a/gcc/function.h b/gcc/function.h
index e92c17c..dd1c38a 100644
--- a/gcc/function.h
+++ b/gcc/function.h
@@ -378,6 +378,9 @@ struct GTY(()) function {
/* Set when the tail call has been identified. */
unsigned int tail_call_marked : 1;
+
+ /* Set when the address of the stack top has been taken. */
+ unsigned int stack_top_taken : 1;
};
/* Add the decl D to the local_decls list of FUN. */
diff --git a/gcc/ipa-pure-const.c b/gcc/ipa-pure-const.c
index 8fd8c36..2405082 100644
--- a/gcc/ipa-pure-const.c
+++ b/gcc/ipa-pure-const.c
@@ -480,6 +480,7 @@ special_builtin_state (enum pure_const_state_e *state, bool *looping,
case BUILT_IN_CXA_END_CLEANUP:
case BUILT_IN_EH_COPY_VALUES:
case BUILT_IN_FRAME_ADDRESS:
+ case BUILT_IN_STACK_TOP:
case BUILT_IN_APPLY:
case BUILT_IN_APPLY_ARGS:
*looping = false;
diff --git a/gcc/target.def b/gcc/target.def
index 4edc209..7a30f39 100644
--- a/gcc/target.def
+++ b/gcc/target.def
@@ -4525,6 +4525,13 @@ argument list due to stack realignment. Return @code{NULL} if no DRAP\n\
is needed.",
rtx, (void), NULL)
+/* Get the stack address when the function is called. */
+DEFHOOK
+(stack_top_rtx,
+ "This hook should return an rtx for the stack address when the function\n\
+is called.",
+ rtx, (void), NULL)
+
/* Return true if all function parameters should be spilled to the
stack. */
DEFHOOK
diff --git a/gcc/targhooks.c b/gcc/targhooks.c
index 3eca47e..f188272 100644
--- a/gcc/targhooks.c
+++ b/gcc/targhooks.c
@@ -1926,4 +1926,13 @@ can_use_doloop_if_innermost (const widest_int &, const widest_int &,
return loop_depth == 1;
}
+/* Get the stack address when the function is called. After the
+ prologue, stack top is at -WORD(AP) in the current frame. */
+
+rtx
+default_stack_top_rtx (void)
+{
+ return plus_constant (Pmode, arg_pointer_rtx, -UNITS_PER_WORD);
+}
+
#include "gt-targhooks.h"
diff --git a/gcc/targhooks.h b/gcc/targhooks.h
index 5ae991d..094a589 100644
--- a/gcc/targhooks.h
+++ b/gcc/targhooks.h
@@ -240,4 +240,7 @@ extern void default_setup_incoming_vararg_bounds (cumulative_args_t ca ATTRIBUTE
tree type ATTRIBUTE_UNUSED,
int *pretend_arg_size ATTRIBUTE_UNUSED,
int second_time ATTRIBUTE_UNUSED);
+
+extern rtx default_stack_top_rtx (void);
+
#endif /* GCC_TARGHOOKS_H */
diff --git a/gcc/testsuite/gcc.target/i386/pr66960-1.c b/gcc/testsuite/gcc.target/i386/pr66960-1.c
new file mode 100644
index 0000000..477d90d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr66960-1.c
@@ -0,0 +1,33 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -fomit-frame-pointer" { target { lp64 } } } */
+/* { dg-options "-O2 -fomit-frame-pointer -maddress-mode=short" { target { x32 } } } */
+/* { dg-options "-O2 -fomit-frame-pointer -miamcu -fno-pic" { target { ia32 } } } */
+
+extern char **environ;
+extern void exit (int status);
+extern int main (long argc, char **argv, char **envp);
+
+void
+_start (void)
+{
+ void *argc_p = __builtin_stack_top ();
+ char **argv = (char **) (argc_p + sizeof (void *));
+ long argc = *(long *) argc_p;
+ int status;
+
+ environ = argv + argc + 1;
+
+ status = main (argc, argv, environ);
+
+ exit (status);
+}
+
+/* { dg-final { scan-assembler "movq\[ \t\]8\\(%rsp\\), %rdi" { target lp64 } } } */
+/* { dg-final { scan-assembler "leaq\[ \t\]16\\(%rsp\\), %rsi" { target lp64 } } } */
+/* { dg-final { scan-assembler "leaq\[ \t\]24\\(%rsp,%rdi,8\\), %rdx" { target lp64 } } } */
+/* { dg-final { scan-assembler "movl\[ \t\]8\\(%esp\\), %edi" { target x32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]12\\(%rsp\\), %esi" { target x32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]4\\(%rsi,%rdi,4\\), %edx" { target x32 } } } */
+/* { dg-final { scan-assembler "movl\[ \t\]\\(%esp\\), %eax" { target ia32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]4\\(%esp\\), %edx" { target ia32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]8\\(%esp,%eax,4\\), %ecx" { target ia32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/pr66960-2.c b/gcc/testsuite/gcc.target/i386/pr66960-2.c
new file mode 100644
index 0000000..b9dbde2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr66960-2.c
@@ -0,0 +1,33 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -fno-omit-frame-pointer" { target { lp64 } } } */
+/* { dg-options "-O2 -fno-omit-frame-pointer -maddress-mode=short" { target { x32 } } } */
+/* { dg-options "-O2 -fno-omit-frame-pointer -miamcu" { target { ia32 } } } */
+
+extern char **environ;
+extern void exit (int status);
+extern int main (long argc, char **argv, char **envp);
+
+void
+_start (void)
+{
+ void *argc_p = __builtin_stack_top ();
+ char **argv = (char **) (argc_p + sizeof (void *));
+ long argc = *(long *) argc_p;
+ int status;
+
+ environ = argv + argc + 1;
+
+ status = main (argc, argv, environ);
+
+ exit (status);
+}
+
+/* { dg-final { scan-assembler "movq\[ \t\]8\\(%rbp\\), %rdi" { target lp64 } } } */
+/* { dg-final { scan-assembler "leaq\[ \t\]16\\(%rbp\\), %rsi" { target lp64 } } } */
+/* { dg-final { scan-assembler "leaq\[ \t\]24\\(%rbp,%rdi,8\\), %rdx" { target lp64 } } } */
+/* { dg-final { scan-assembler "movl\[ \t\]8\\(%ebp\\), %edi" { target x32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]12\\(%rbp\\), %esi" { target x32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]4\\(%rsi,%rdi,4\\), %edx" { target x32 } } } */
+/* { dg-final { scan-assembler "movl\[ \t\]4\\(%ebp\\), %eax" { target ia32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]8\\(%ebp\\), %edx" { target ia32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]12\\(%ebp,%eax,4\\), %ecx" { target ia32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/pr66960-3.c b/gcc/testsuite/gcc.target/i386/pr66960-3.c
new file mode 100644
index 0000000..48cf25e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr66960-3.c
@@ -0,0 +1,17 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -mno-accumulate-outgoing-args" { target { lp64 } } } */
+/* { dg-options "-O2 -mno-accumulate-outgoing-args -maddress-mode=short" { target { x32 } } } */
+/* { dg-options "-O2 -mno-accumulate-outgoing-args -miamcu" { target { ia32 } } } */
+
+extern void abort (void);
+extern int check_int (int *i, int align);
+typedef int aligned __attribute__((aligned(64)));
+
+void *
+foo (void)
+{
+ aligned j;
+ if (check_int (&j, __alignof__(j)) != j)
+ abort ();
+ return __builtin_stack_top ();
+} /* { dg-message "sorry, unimplemented: .__builtin_stack_top. not supported" } */
diff --git a/gcc/testsuite/gcc.target/i386/pr66960-4.c b/gcc/testsuite/gcc.target/i386/pr66960-4.c
new file mode 100644
index 0000000..44c0b26
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr66960-4.c
@@ -0,0 +1,21 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -maccumulate-outgoing-args" { target { lp64 } } } */
+/* { dg-options "-O2 -maccumulate-outgoing-args -maddress-mode=short" { target { x32 } } } */
+/* { dg-options "-O2 -maccumulate-outgoing-args -miamcu" { target { ia32 } } } */
+
+extern void abort (void);
+extern int check_int (int *i, int align);
+typedef int aligned __attribute__((aligned(64)));
+
+void *
+foo (void)
+{
+ aligned j;
+ if (check_int (&j, __alignof__(j)) != j)
+ abort ();
+ return __builtin_stack_top ();
+}
+
+/* { dg-final { scan-assembler "leaq\[ \t\]8\\(%rbp\\), %rax" { target lp64 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]8\\(%rbp\\), %eax" { target x32 } } } */
+/* { dg-final { scan-assembler "leal\[ \t\]4\\(%ebp\\), %eax" { target ia32 } } } */
diff --git a/gcc/testsuite/gcc.target/i386/pr66960-5.c b/gcc/testsuite/gcc.target/i386/pr66960-5.c
new file mode 100644
index 0000000..d449437
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr66960-5.c
@@ -0,0 +1,21 @@
+/* { dg-do link } */
+/* { dg-options "-O" } */
+
+extern void link_error (void);
+
+__attribute__ ((noinline, noclone))
+void
+foo (void)
+{
+ void **p = __builtin_stack_top ();
+ void *ra = __builtin_return_address (0);
+ if (*p != ra)
+ link_error ();
+}
+
+int
+main (void)
+{
+ foo ();
+ return 0;
+}
--
2.4.3