diff mbox

[GCC/ARM,gcc-5/6-branch,ping] Fix PR77904: callee-saved register trashed when clobbering sp

Message ID 51cb2ae9-71c1-540a-6c7c-dc960adcbabf@foss.arm.com
State New
Headers show

Commit Message

Thomas Preudhomme Dec. 12, 2016, 10:44 a.m. UTC
Same as for PR77933, I'm trying to get this in for the next GCC 6 release.

I've successfully done a Thumb-1 bootstrap of the backport and testsuite shows 
no regression when run with an arm-none-eabi GCC cross-compiler targeting ARM 
Cortex-M0.

Is this ok for gcc-6-branch?

Best regards,

Thomas

On 06/12/16 11:38, Thomas Preudhomme wrote:
> Ping?

>

> Best regards,

>

> Thomas

>

> On 30/11/16 10:44, Thomas Preudhomme wrote:

>> Sorry, the bug cannot be reproduced on gcc-5-branch so it's probably better to

>> only do a backport to gcc-6-branch.

>>

>> Ok for a backport to gcc-6-branch?

>>

>> Best regards,

>>

>> Thomas

>>

>> On 30/11/16 10:42, Thomas Preudhomme wrote:

>>> Hi,

>>>

>>> Is this ok to backport to gcc-5-branch and gcc-6-branch? Patch applies cleanly

>>> (patches attached for reference).

>>>

>>>

>>> 2016-11-30 Thomas Preud'homme <thomas.preudhomme@arm.com>

>>>

>>>     Backport from mainline

>>>     2016-11-22  Thomas Preud'homme  <thomas.preudhomme@arm.com>

>>>

>>>     gcc/

>>>     PR target/77904

>>>     * config/arm/arm.c (thumb1_compute_save_reg_mask): Mark frame pointer

>>>     in save register mask if it is needed.

>>>

>>>     gcc/testsuite/

>>>     PR target/77904

>>>     * gcc.target/arm/pr77904.c: New test.

>>>

>>>

>>> Best regards,

>>>

>>> Thomas

>>>

>>>

>>> On 22/11/16 10:45, Thomas Preudhomme wrote:

>>>> On 17/11/16 09:11, Kyrill Tkachov wrote:

>>>>>

>>>>> On 17/11/16 08:56, Thomas Preudhomme wrote:

>>>>>> On 16/11/16 10:30, Kyrill Tkachov wrote:

>>>>>>> Hi Thomas,

>>>>>>>

>>>>>>> On 03/11/16 16:52, Thomas Preudhomme wrote:

>>>>>>>> Hi,

>>>>>>>>

>>>>>>>> When using a callee-saved register to save the frame pointer the Thumb-1

>>>>>>>> prologue fails to save the callee-saved register before that. For ARM and

>>>>>>>> Thumb-2 targets the frame pointer is handled as a special case but

>>>>>>>> nothing is

>>>>>>>> done for Thumb-1 targets. This patch adds the same logic for Thumb-1

>>>>>>>> targets.

>>>>>>>>

>>>>>>>> ChangeLog entries are as follow:

>>>>>>>>

>>>>>>>> *** gcc/ChangeLog ***

>>>>>>>>

>>>>>>>> 2016-11-02  Thomas Preud'homme <thomas.preudhomme@arm.com>

>>>>>>>>

>>>>>>>>         PR target/77904

>>>>>>>>         * config/arm/arm.c (thumb1_compute_save_reg_mask): mark frame

>>>>>>>> pointer

>>>>>>>>         in save register mask if it is needed.

>>>>>>>>

>>>>>>>

>>>>>>> s/mark/Mark/

>>>>>>>

>>>>>>>>

>>>>>>>> *** gcc/testsuite/ChangeLog ***

>>>>>>>>

>>>>>>>> 2016-11-02  Thomas Preud'homme <thomas.preudhomme@arm.com>

>>>>>>>>

>>>>>>>>         PR target/77904

>>>>>>>>         * gcc.target/arm/pr77904.c: New test.

>>>>>>>>

>>>>>>>>

>>>>>>>> Testing: Testsuite shows no regression when run with arm-none-eabi GCC

>>>>>>>> cross-compiler for Cortex-M0 target.

>>>>>>>>

>>>>>>>> Is this ok for trunk?

>>>>>>>>

>>>>>>>

>>>>>>> I'd ask for a bootstrap, but this code is Thumb-1 only so it wouldn't affect

>>>>>>> anything.

>>>>>>

>>>>>> I can bootstrap for armv4t with --with-mode=thumb which would at least

>>>>>> exercise the path. I'll try such a bootstrap on qemu.

>>>>>>

>>>>>

>>>>> If you can get it to work, then yes please.

>>>>

>>>> Bootstrap came back clean so I've committed the patch (r242693). Thanks!

>>>>

>>>> Best regards,

>>>>

>>>> Thomas

Comments

Kyrill Tkachov Dec. 12, 2016, 10:46 a.m. UTC | #1
On 12/12/16 10:44, Thomas Preudhomme wrote:
> Same as for PR77933, I'm trying to get this in for the next GCC 6 release.

>

> I've successfully done a Thumb-1 bootstrap of the backport and testsuite shows no regression when run with an arm-none-eabi GCC cross-compiler targeting ARM Cortex-M0.

>

> Is this ok for gcc-6-branch?

>


Given this has been in trunk for some time, is specific to Thumb-1 and fixes a wrong-code issue this is ok.
Thanks,
Kyrill

> Best regards,

>

> Thomas

>

> On 06/12/16 11:38, Thomas Preudhomme wrote:

>> Ping?

>>

>> Best regards,

>>

>> Thomas

>>

>> On 30/11/16 10:44, Thomas Preudhomme wrote:

>>> Sorry, the bug cannot be reproduced on gcc-5-branch so it's probably better to

>>> only do a backport to gcc-6-branch.

>>>

>>> Ok for a backport to gcc-6-branch?

>>>

>>> Best regards,

>>>

>>> Thomas

>>>

>>> On 30/11/16 10:42, Thomas Preudhomme wrote:

>>>> Hi,

>>>>

>>>> Is this ok to backport to gcc-5-branch and gcc-6-branch? Patch applies cleanly

>>>> (patches attached for reference).

>>>>

>>>>

>>>> 2016-11-30 Thomas Preud'homme <thomas.preudhomme@arm.com>

>>>>

>>>>     Backport from mainline

>>>>     2016-11-22  Thomas Preud'homme <thomas.preudhomme@arm.com>

>>>>

>>>>     gcc/

>>>>     PR target/77904

>>>>     * config/arm/arm.c (thumb1_compute_save_reg_mask): Mark frame pointer

>>>>     in save register mask if it is needed.

>>>>

>>>>     gcc/testsuite/

>>>>     PR target/77904

>>>>     * gcc.target/arm/pr77904.c: New test.

>>>>

>>>>

>>>> Best regards,

>>>>

>>>> Thomas

>>>>

>>>>

>>>> On 22/11/16 10:45, Thomas Preudhomme wrote:

>>>>> On 17/11/16 09:11, Kyrill Tkachov wrote:

>>>>>>

>>>>>> On 17/11/16 08:56, Thomas Preudhomme wrote:

>>>>>>> On 16/11/16 10:30, Kyrill Tkachov wrote:

>>>>>>>> Hi Thomas,

>>>>>>>>

>>>>>>>> On 03/11/16 16:52, Thomas Preudhomme wrote:

>>>>>>>>> Hi,

>>>>>>>>>

>>>>>>>>> When using a callee-saved register to save the frame pointer the Thumb-1

>>>>>>>>> prologue fails to save the callee-saved register before that. For ARM and

>>>>>>>>> Thumb-2 targets the frame pointer is handled as a special case but

>>>>>>>>> nothing is

>>>>>>>>> done for Thumb-1 targets. This patch adds the same logic for Thumb-1

>>>>>>>>> targets.

>>>>>>>>>

>>>>>>>>> ChangeLog entries are as follow:

>>>>>>>>>

>>>>>>>>> *** gcc/ChangeLog ***

>>>>>>>>>

>>>>>>>>> 2016-11-02  Thomas Preud'homme <thomas.preudhomme@arm.com>

>>>>>>>>>

>>>>>>>>>         PR target/77904

>>>>>>>>>         * config/arm/arm.c (thumb1_compute_save_reg_mask): mark frame

>>>>>>>>> pointer

>>>>>>>>>         in save register mask if it is needed.

>>>>>>>>>

>>>>>>>>

>>>>>>>> s/mark/Mark/

>>>>>>>>

>>>>>>>>>

>>>>>>>>> *** gcc/testsuite/ChangeLog ***

>>>>>>>>>

>>>>>>>>> 2016-11-02  Thomas Preud'homme <thomas.preudhomme@arm.com>

>>>>>>>>>

>>>>>>>>>         PR target/77904

>>>>>>>>>         * gcc.target/arm/pr77904.c: New test.

>>>>>>>>>

>>>>>>>>>

>>>>>>>>> Testing: Testsuite shows no regression when run with arm-none-eabi GCC

>>>>>>>>> cross-compiler for Cortex-M0 target.

>>>>>>>>>

>>>>>>>>> Is this ok for trunk?

>>>>>>>>>

>>>>>>>>

>>>>>>>> I'd ask for a bootstrap, but this code is Thumb-1 only so it wouldn't affect

>>>>>>>> anything.

>>>>>>>

>>>>>>> I can bootstrap for armv4t with --with-mode=thumb which would at least

>>>>>>> exercise the path. I'll try such a bootstrap on qemu.

>>>>>>>

>>>>>>

>>>>>> If you can get it to work, then yes please.

>>>>>

>>>>> Bootstrap came back clean so I've committed the patch (r242693). Thanks!

>>>>>

>>>>> Best regards,

>>>>>

>>>>> Thomas
diff mbox

Patch

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 83cb13d1195beb19d6301f5c83a7eb544a91d877..ae479a43fe8514f2eacb7d56f89916b48f720768 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -19390,6 +19390,10 @@  thumb1_compute_save_reg_mask (void)
     if (df_regs_ever_live_p (reg) && callee_saved_reg_p (reg))
       mask |= 1 << reg;
 
+  /* Handle the frame pointer as a special case.  */
+  if (frame_pointer_needed)
+    mask |= 1 << HARD_FRAME_POINTER_REGNUM;
+
   if (flag_pic
       && !TARGET_SINGLE_PIC_BASE
       && arm_pic_register != INVALID_REGNUM
diff --git a/gcc/testsuite/gcc.target/arm/pr77904.c b/gcc/testsuite/gcc.target/arm/pr77904.c
new file mode 100644
index 0000000000000000000000000000000000000000..76728c07e73350ce44160cabff3dd2fa7a6ef021
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/pr77904.c
@@ -0,0 +1,45 @@ 
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+__attribute__ ((noinline, noclone)) void
+clobber_sp (void)
+{
+  __asm volatile ("" : : : "sp");
+}
+
+int
+main (void)
+{
+  int ret;
+
+  __asm volatile ("mov\tr4, #0xf4\n\t"
+		  "mov\tr5, #0xf5\n\t"
+		  "mov\tr6, #0xf6\n\t"
+		  "mov\tr7, #0xf7\n\t"
+		  "mov\tr0, #0xf8\n\t"
+		  "mov\tr8, r0\n\t"
+		  "mov\tr0, #0xfa\n\t"
+		  "mov\tr10, r0"
+		  : : : "r0", "r4", "r5", "r6", "r7", "r8", "r10");
+  clobber_sp ();
+
+  __asm volatile ("cmp\tr4, #0xf4\n\t"
+		  "bne\tfail\n\t"
+		  "cmp\tr5, #0xf5\n\t"
+		  "bne\tfail\n\t"
+		  "cmp\tr6, #0xf6\n\t"
+		  "bne\tfail\n\t"
+		  "cmp\tr7, #0xf7\n\t"
+		  "bne\tfail\n\t"
+		  "mov\tr0, r8\n\t"
+		  "cmp\tr0, #0xf8\n\t"
+		  "bne\tfail\n\t"
+		  "mov\tr0, r10\n\t"
+		  "cmp\tr0, #0xfa\n\t"
+		  "bne\tfail\n\t"
+		  "mov\t%0, #1\n"
+		  "fail:\n\t"
+		  "sub\tr0, #1"
+		  : "=r" (ret) : :);
+  return ret;
+}