[PATCH 1/4][ARM][PR target/65697][5.1] Backport stronger barriers for __sync fetch-op builtins.

[PATCH 1/4][ARM][PR target/65697][5.1] Backport stronger barriers for __sync fetch-op builtins.

[Matthew Wahab]

[-- Attachment #1: Type: text/plain, Size: 850 bytes --]

The __sync builtins are implemented using barriers that are too weak for ARMv8
targets, this has been fixed on trunk for the ARM back-end. Since GCC-5.1 is
also generating the incorrect code, it should also be fixed.

This patch backports the changes made to strengthen the barriers emitted for
the __sync fetch-and-op/op-and-fetch builtins.

The trunk patch submission is at
https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01410.html
The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01235.html

Tested the series for arm-none-linux-gnueabihf with check-gcc

Ok for the branch?
Matthew

2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>

	Backport from trunk:
	2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>

	PR target/65697
	* config/armc/arm.c (arm_split_atomic_op): For ARMv8, replace an
	initial acquire barrier with final barrier.

[-- Attachment #2: 0001-2015-07-01-Matthew-Wahab-matthew.wahab-arm.com.patch --]
[-- Type: text/x-patch, Size: 2082 bytes --]

From e7150c85313fff08153197493db568ca8fe2778a Mon Sep 17 00:00:00 2001
From: mwahab <mwahab@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 29 Jun 2015 16:03:34 +0000
Subject: [PATCH 1/4] 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

        Backport
	PR target/65697
	* config/armc/arm.c (arm_split_atomic_op): For ARMv8, replace an
	initial acquire barrier with final barrier.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225132 138bc75d-0d04-0410-961f-82ee72b054a4

Conflicts:
	gcc/ChangeLog

Change-Id: I2074541794ecad8847ada04690cd9132a51b6404
---
 gcc/config/arm/arm.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 7b279c7..b36dfb0 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -27807,6 +27807,8 @@ arm_split_atomic_op (enum rtx_code code, rtx old_out, rtx new_out, rtx mem,
   rtx_code_label *label;
   rtx x;
 
+  bool is_armv8_sync = arm_arch8 && is_mm_sync (model);
+
   bool use_acquire = TARGET_HAVE_LDACQ
                      && !(is_mm_relaxed (model) || is_mm_consume (model)
 			  || is_mm_release (model));
@@ -27815,6 +27817,11 @@ arm_split_atomic_op (enum rtx_code code, rtx old_out, rtx new_out, rtx mem,
                      && !(is_mm_relaxed (model) || is_mm_consume (model)
 			  || is_mm_acquire (model));
 
+  /* For ARMv8, a load-acquire is too weak for __sync memory orders.  Instead,
+     a full barrier is emitted after the store-release.  */
+  if (is_armv8_sync)
+    use_acquire = false;
+
   /* Checks whether a barrier is needed and emits one accordingly.  */
   if (!(use_acquire || use_release))
     arm_pre_atomic_barrier (model);
@@ -27885,7 +27892,8 @@ arm_split_atomic_op (enum rtx_code code, rtx old_out, rtx new_out, rtx mem,
   emit_unlikely_jump (gen_cbranchsi4 (x, cond, const0_rtx, label));
 
   /* Checks whether a barrier is needed and emits one accordingly.  */
-  if (!(use_acquire || use_release))
+  if (is_armv8_sync
+      || !(use_acquire || use_release))
     arm_post_atomic_barrier (model);
 }
 \f
-- 
1.9.1

[PATCH 2/4][ARM][PR target/65697][5.1] Backport stronger barriers for __sync,compare-and-swap builtins.

[Matthew Wahab]

[-- Attachment #1: Type: text/plain, Size: 631 bytes --]

This patch backports the changes made to strengthen the barriers emitted for
the __sync compare-and-swap builtins.

The trunk patch submission is at
https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01411.html
The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01236.html

Tested the series for arm-none-linux-gnueabihf with check-gcc

Ok for the branch?
Matthew

2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>

	Backport from trunk:
	2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>

	PR target/65697
	* config/armc/arm.c (arm_split_compare_and_swap): For ARMv8,
	replace an initial acquire barrier with final barrier.


[-- Attachment #2: 0002-2015-07-01-Matthew-Wahab-matthew.wahab-arm.com.patch --]
[-- Type: text/x-patch, Size: 1987 bytes --]

From fce96ded43d39847473b67e54e3146924c703f40 Mon Sep 17 00:00:00 2001
From: mwahab <mwahab@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 29 Jun 2015 16:09:10 +0000
Subject: [PATCH 2/4] 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

	Backport
	PR target/65697
	* config/armc/arm.c (arm_split_compare_and_swap): For ARMv8, replace an
	initial acquire barrier with final barrier.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225133 138bc75d-0d04-0410-961f-82ee72b054a4

Conflicts:
	gcc/ChangeLog

Change-Id: Ifab505d792d6227c7d2231813dfb2e7826f0f450
---
 gcc/config/arm/arm.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index b36dfb0..49005fb 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -27742,6 +27742,8 @@ arm_split_compare_and_swap (rtx operands[])
   scratch = operands[7];
   mode = GET_MODE (mem);
 
+  bool is_armv8_sync = arm_arch8 && is_mm_sync (mod_s);
+
   bool use_acquire = TARGET_HAVE_LDACQ
                      && !(is_mm_relaxed (mod_s) || is_mm_consume (mod_s)
 			  || is_mm_release (mod_s));
@@ -27750,6 +27752,11 @@ arm_split_compare_and_swap (rtx operands[])
                      && !(is_mm_relaxed (mod_s) || is_mm_consume (mod_s)
 			  || is_mm_acquire (mod_s));
 
+  /* For ARMv8, the load-acquire is too weak for __sync memory orders.  Instead,
+     a full barrier is emitted after the store-release.  */
+  if (is_armv8_sync)
+    use_acquire = false;
+
   /* Checks whether a barrier is needed and emits one accordingly.  */
   if (!(use_acquire || use_release))
     arm_pre_atomic_barrier (mod_s);
@@ -27790,7 +27797,8 @@ arm_split_compare_and_swap (rtx operands[])
     emit_label (label2);
 
   /* Checks whether a barrier is needed and emits one accordingly.  */
-  if (!(use_acquire || use_release))
+  if (is_armv8_sync
+      || !(use_acquire || use_release))
     arm_post_atomic_barrier (mod_s);
 
   if (is_mm_relaxed (mod_f))
-- 
1.9.1

[PATCH 3/4][ARM][PR target/65697][5.1] Add tests for __sync_builtins.

[Matthew Wahab]

[-- Attachment #1: Type: text/plain, Size: 697 bytes --]

This patch backports the tests added for code generated by the ARM back-end for
the __sync builtins.

The trunk patch submission is at
https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01412.html
The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01237.html

Tested the series for arm-none-linux-gnueabihf with check-gcc

Ok for the branch?
Matthew

gcc/testsuite
2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>

	Backport from trunk:
	2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>

	PR target/65697
	* gcc.target/arm/armv-sync-comp-swap.c: New.
	* gcc.target/arm/armv-sync-op-acquire.c: New.
	* gcc.target/arm/armv-sync-op-full.c: New.
	* gcc.target/arm/armv-sync-op-release.c: New.


[-- Attachment #2: 0003-2015-07-01-Matthew-Wahab-matthew.wahab-arm.com.patch --]
[-- Type: text/x-patch, Size: 3559 bytes --]

From 27eb0d570c831be52f4d544bf40abe8a6a4246c3 Mon Sep 17 00:00:00 2001
From: mwahab <mwahab@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 29 Jun 2015 16:12:12 +0000
Subject: [PATCH 3/4] 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

	Backport
	PR target/65697
	* gcc.target/arm/armv-sync-comp-swap.c: New.
	* gcc.target/arm/armv-sync-op-acquire.c: New.
	* gcc.target/arm/armv-sync-op-full.c: New.
	* gcc.target/arm/armv-sync-op-release.c: New.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225134 138bc75d-0d04-0410-961f-82ee72b054a4

Conflicts:
	gcc/ChangeLog

Change-Id: I16c02786765bbbfbb287fba863ba27fb6a56ddc5
---
 gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c  | 10 ++++++++++
 gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c | 10 ++++++++++
 gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c    | 10 ++++++++++
 gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c |  8 ++++++++
 4 files changed, 38 insertions(+)
 create mode 100644 gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
 create mode 100644 gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
 create mode 100644 gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
 create mode 100644 gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c

diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c b/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
new file mode 100644
index 0000000..f96c81a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_arch_v8a } */
+
+#include "../aarch64/sync-comp-swap.x"
+
+/* { dg-final { scan-assembler-times "ldrex" 2 } } */
+/* { dg-final { scan-assembler-times "stlex" 2 } } */
+/* { dg-final { scan-assembler-times "dmb" 2 } } */
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
new file mode 100644
index 0000000..8d6659b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_arch_v8a } */
+
+#include "../aarch64/sync-op-acquire.x"
+
+/* { dg-final { scan-assembler-times "ldrex" 1 } } */
+/* { dg-final { scan-assembler-times "stlex" 1 } } */
+/* { dg-final { scan-assembler-times "dmb" 1 } } */
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
new file mode 100644
index 0000000..a5ad3bd
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_arch_v8a } */
+
+#include "../aarch64/sync-op-full.x"
+
+/* { dg-final { scan-assembler-times "ldrex" 12 } } */
+/* { dg-final { scan-assembler-times "stlex" 12 } } */
+/* { dg-final { scan-assembler-times "dmb" 12 } } */
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
new file mode 100644
index 0000000..0d3be7b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
@@ -0,0 +1,8 @@
+/* { dg-do compile } */
+/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_arch_v8a } */
+
+#include "../aarch64/sync-op-release.x"
+
+/* { dg-final { scan-assembler-times "stl" 1 } } */
-- 
1.9.1

[PATCH 4/4][ARM][PR target/65697][5.1] Fix tests for __sync_builtins.

[Matthew Wahab]

[-- Attachment #1: Type: text/plain, Size: 786 bytes --]

This patch backports fixes for the __sync builtin tests.

The trunk patch submission is at
https://gcc.gnu.org/ml/gcc-patches/2015-07/msg00031.html
The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-07/msg00025.html

Tested the series for arm-none-linux-gnueabihf with check-gcc

Ok for the branch?
Matthew

gcc/testsuite
2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>

	Backport from trunk:
	2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

	* gcc.target/arm/armv8-sync-comp-swap.c: Replace
	'do-require-effective-target' with 'dg-require-effective-target'.
	* gcc.target/arm/armv8-sync-op-full.c: Likewise.
	* gcc.target/arm/armv8-sync-op-release.c: Likewise.
	* gcc.target/arm/armv8-sync-op-acquire.c: Likewise.  Also, replace
	'stlex' with 'strex' as the expected output.


[-- Attachment #2: 0004-2015-07-01-Matthew-Wahab-matthew.wahab-arm.com.patch --]
[-- Type: text/x-patch, Size: 3290 bytes --]

From 3e48ba2ea1848ca9d17d627ebbdc9c6fb2e8c21b Mon Sep 17 00:00:00 2001
From: mwahab <mwahab@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Wed, 1 Jul 2015 12:16:01 +0000
Subject: [PATCH 4/4] 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

	Backport
	* gcc.target/arm/armv8-sync-comp-swap.c: Replace
	'do-require-effective-target' with 'dg-require-effective-target'.
	* gcc.target/arm/armv8-sync-op-full.c: Likewise.
	* gcc.target/arm/armv8-sync-op-release.c: Likewise.
	* gcc.target/arm/armv8-sync-op-acquire.c: Likewise.  Also, replace
        'stlex' with 'strex' as the expected output.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225241 138bc75d-0d04-0410-961f-82ee72b054a4

Conflicts:
	gcc/testsuite/ChangeLog

Change-Id: I19f2013f7bdd2dd035f36f0f7c9829cf6a86fb8e
---
 gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c  | 2 +-
 gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c | 4 ++--
 gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c    | 2 +-
 gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c b/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
index f96c81a..0e95986 100644
--- a/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-require-effective-target arm_arch_v8a_ok } */
 /* { dg-options "-O2" } */
 /* { dg-add-options arm_arch_v8a } */
 
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
index 8d6659b..c448599 100644
--- a/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
@@ -1,10 +1,10 @@
 /* { dg-do compile } */
-/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-require-effective-target arm_arch_v8a_ok } */
 /* { dg-options "-O2" } */
 /* { dg-add-options arm_arch_v8a } */
 
 #include "../aarch64/sync-op-acquire.x"
 
 /* { dg-final { scan-assembler-times "ldrex" 1 } } */
-/* { dg-final { scan-assembler-times "stlex" 1 } } */
+/* { dg-final { scan-assembler-times "strex" 1 } } */
 /* { dg-final { scan-assembler-times "dmb" 1 } } */
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
index a5ad3bd..cce9e00 100644
--- a/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-require-effective-target arm_arch_v8a_ok } */
 /* { dg-options "-O2" } */
 /* { dg-add-options arm_arch_v8a } */
 
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
index 0d3be7b..502a266 100644
--- a/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-require-effective-target arm_arch_v8a_ok } */
 /* { dg-options "-O2" } */
 /* { dg-add-options arm_arch_v8a } */
 
-- 
1.9.1

Re: [PATCH 1/4][ARM][PR target/65697][5.1] Backport stronger barriers for __sync fetch-op builtins.

[Matthew Wahab]

[-- Attachment #1: Type: text/plain, Size: 1119 bytes --]

Ping. Updated patch attached.

Also, retested for arm-none-linux-gnueabihf with native bootstrap and make
check and for arm-none-eabi with cross compiled make check.

On 02/07/15 14:12, Matthew Wahab wrote:
> The __sync builtins are implemented using barriers that are too weak for ARMv8
> targets, this has been fixed on trunk for the ARM back-end. Since GCC-5.1 is
> also generating the incorrect code, it should also be fixed.
>
> This patch backports the changes made to strengthen the barriers emitted for
> the __sync fetch-and-op/op-and-fetch builtins.
>
> The trunk patch submission is at
> https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01410.html
> The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01235.html
>
> Tested the series for arm-none-linux-gnueabihf with check-gcc
>
> Ok for the branch?
> Matthew
>
> 2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>
>
>      Backport from trunk:
>      2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>
>
>      PR target/65697
>      * config/armc/arm.c (arm_split_atomic_op): For ARMv8, replace an
>      initial acquire barrier with final barrier.


[-- Attachment #2: 0001-2015-07-01-Matthew-Wahab-matthew.wahab-arm.com.patch --]
[-- Type: text/x-patch, Size: 2082 bytes --]

From 0c2f209f869aead3475fe491f08cf7640d2bc8fe Mon Sep 17 00:00:00 2001
From: mwahab <mwahab@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 29 Jun 2015 16:03:34 +0000
Subject: [PATCH 1/4] 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

        Backport
	PR target/65697
	* config/armc/arm.c (arm_split_atomic_op): For ARMv8, replace an
	initial acquire barrier with final barrier.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225132 138bc75d-0d04-0410-961f-82ee72b054a4

Conflicts:
	gcc/ChangeLog

Change-Id: I2074541794ecad8847ada04690cd9132a51b6404
---
 gcc/config/arm/arm.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 614ff0d..f694e74 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -27822,6 +27822,8 @@ arm_split_atomic_op (enum rtx_code code, rtx old_out, rtx new_out, rtx mem,
   rtx_code_label *label;
   rtx x;
 
+  bool is_armv8_sync = arm_arch8 && is_mm_sync (model);
+
   bool use_acquire = TARGET_HAVE_LDACQ
                      && !(is_mm_relaxed (model) || is_mm_consume (model)
 			  || is_mm_release (model));
@@ -27830,6 +27832,11 @@ arm_split_atomic_op (enum rtx_code code, rtx old_out, rtx new_out, rtx mem,
                      && !(is_mm_relaxed (model) || is_mm_consume (model)
 			  || is_mm_acquire (model));
 
+  /* For ARMv8, a load-acquire is too weak for __sync memory orders.  Instead,
+     a full barrier is emitted after the store-release.  */
+  if (is_armv8_sync)
+    use_acquire = false;
+
   /* Checks whether a barrier is needed and emits one accordingly.  */
   if (!(use_acquire || use_release))
     arm_pre_atomic_barrier (model);
@@ -27900,7 +27907,8 @@ arm_split_atomic_op (enum rtx_code code, rtx old_out, rtx new_out, rtx mem,
   emit_unlikely_jump (gen_cbranchsi4 (x, cond, const0_rtx, label));
 
   /* Checks whether a barrier is needed and emits one accordingly.  */
-  if (!(use_acquire || use_release))
+  if (is_armv8_sync
+      || !(use_acquire || use_release))
     arm_post_atomic_barrier (model);
 }
 \f
-- 
1.9.1

Re: [PATCH 2/4][ARM][PR target/65697][5.1] Backport stronger barriers for __sync,compare-and-swap builtins.

[Matthew Wahab]

[-- Attachment #1: Type: text/plain, Size: 895 bytes --]

Ping. Updated patch attached.

Also, retested for arm-none-linux-gnueabihf with native bootstrap and make
check and for arm-none-eabi with cross compiled make check.


On 02/07/15 14:15, Matthew Wahab wrote:
> This patch backports the changes made to strengthen the barriers emitted for
> the __sync compare-and-swap builtins.
>
> The trunk patch submission is at
> https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01411.html
> The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01236.html
>
> Tested the series for arm-none-linux-gnueabihf with check-gcc
>
> Ok for the branch?
> Matthew
>
> 2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>
>
>      Backport from trunk:
>      2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>
>
>      PR target/65697
>      * config/armc/arm.c (arm_split_compare_and_swap): For ARMv8,
>      replace an initial acquire barrier with final barrier.
>


[-- Attachment #2: 0002-2015-07-01-Matthew-Wahab-matthew.wahab-arm.com.patch --]
[-- Type: text/x-patch, Size: 1987 bytes --]

From fdcde1aa0b852f2a01bb45115e28f694b0225fcf Mon Sep 17 00:00:00 2001
From: mwahab <mwahab@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 29 Jun 2015 16:09:10 +0000
Subject: [PATCH 2/4] 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

	Backport
	PR target/65697
	* config/armc/arm.c (arm_split_compare_and_swap): For ARMv8, replace an
	initial acquire barrier with final barrier.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225133 138bc75d-0d04-0410-961f-82ee72b054a4

Conflicts:
	gcc/ChangeLog

Change-Id: Ifab505d792d6227c7d2231813dfb2e7826f0f450
---
 gcc/config/arm/arm.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index f694e74..1e67a73 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -27757,6 +27757,8 @@ arm_split_compare_and_swap (rtx operands[])
   scratch = operands[7];
   mode = GET_MODE (mem);
 
+  bool is_armv8_sync = arm_arch8 && is_mm_sync (mod_s);
+
   bool use_acquire = TARGET_HAVE_LDACQ
                      && !(is_mm_relaxed (mod_s) || is_mm_consume (mod_s)
 			  || is_mm_release (mod_s));
@@ -27765,6 +27767,11 @@ arm_split_compare_and_swap (rtx operands[])
                      && !(is_mm_relaxed (mod_s) || is_mm_consume (mod_s)
 			  || is_mm_acquire (mod_s));
 
+  /* For ARMv8, the load-acquire is too weak for __sync memory orders.  Instead,
+     a full barrier is emitted after the store-release.  */
+  if (is_armv8_sync)
+    use_acquire = false;
+
   /* Checks whether a barrier is needed and emits one accordingly.  */
   if (!(use_acquire || use_release))
     arm_pre_atomic_barrier (mod_s);
@@ -27805,7 +27812,8 @@ arm_split_compare_and_swap (rtx operands[])
     emit_label (label2);
 
   /* Checks whether a barrier is needed and emits one accordingly.  */
-  if (!(use_acquire || use_release))
+  if (is_armv8_sync
+      || !(use_acquire || use_release))
     arm_post_atomic_barrier (mod_s);
 
   if (is_mm_relaxed (mod_f))
-- 
1.9.1

Re: [PATCH 3/4][ARM][PR target/65697][5.1] Add tests for __sync_builtins.

[Matthew Wahab]

[-- Attachment #1: Type: text/plain, Size: 974 bytes --]

Ping. Updated patch attached.

Also, retested for arm-none-linux-gnueabihf with native bootstrap and make
check and for arm-none-eabi with cross compiled make check.

On 02/07/15 14:17, Matthew Wahab wrote:
> This patch backports the tests added for code generated by the ARM back-end for
> the __sync builtins.
>
> The trunk patch submission is at
> https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01412.html
> The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01237.html
>
> Tested the series for arm-none-linux-gnueabihf with check-gcc
>
> Ok for the branch?
> Matthew
>
> gcc/testsuite
> 2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>
>
>      Backport from trunk:
>      2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>
>
>      PR target/65697
>      * gcc.target/arm/armv-sync-comp-swap.c: New.
>      * gcc.target/arm/armv-sync-op-acquire.c: New.
>      * gcc.target/arm/armv-sync-op-full.c: New.
>      * gcc.target/arm/armv-sync-op-release.c: New.
>


[-- Attachment #2: 0003-2015-07-01-Matthew-Wahab-matthew.wahab-arm.com.patch --]
[-- Type: text/x-patch, Size: 3559 bytes --]

From d1a53325eb47a5da55a8267deb5fbe168f7db4de Mon Sep 17 00:00:00 2001
From: mwahab <mwahab@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 29 Jun 2015 16:12:12 +0000
Subject: [PATCH 3/4] 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

	Backport
	PR target/65697
	* gcc.target/arm/armv-sync-comp-swap.c: New.
	* gcc.target/arm/armv-sync-op-acquire.c: New.
	* gcc.target/arm/armv-sync-op-full.c: New.
	* gcc.target/arm/armv-sync-op-release.c: New.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225134 138bc75d-0d04-0410-961f-82ee72b054a4

Conflicts:
	gcc/ChangeLog

Change-Id: I16c02786765bbbfbb287fba863ba27fb6a56ddc5
---
 gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c  | 10 ++++++++++
 gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c | 10 ++++++++++
 gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c    | 10 ++++++++++
 gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c |  8 ++++++++
 4 files changed, 38 insertions(+)
 create mode 100644 gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
 create mode 100644 gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
 create mode 100644 gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
 create mode 100644 gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c

diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c b/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
new file mode 100644
index 0000000..f96c81a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_arch_v8a } */
+
+#include "../aarch64/sync-comp-swap.x"
+
+/* { dg-final { scan-assembler-times "ldrex" 2 } } */
+/* { dg-final { scan-assembler-times "stlex" 2 } } */
+/* { dg-final { scan-assembler-times "dmb" 2 } } */
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
new file mode 100644
index 0000000..8d6659b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_arch_v8a } */
+
+#include "../aarch64/sync-op-acquire.x"
+
+/* { dg-final { scan-assembler-times "ldrex" 1 } } */
+/* { dg-final { scan-assembler-times "stlex" 1 } } */
+/* { dg-final { scan-assembler-times "dmb" 1 } } */
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
new file mode 100644
index 0000000..a5ad3bd
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_arch_v8a } */
+
+#include "../aarch64/sync-op-full.x"
+
+/* { dg-final { scan-assembler-times "ldrex" 12 } } */
+/* { dg-final { scan-assembler-times "stlex" 12 } } */
+/* { dg-final { scan-assembler-times "dmb" 12 } } */
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
new file mode 100644
index 0000000..0d3be7b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
@@ -0,0 +1,8 @@
+/* { dg-do compile } */
+/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_arch_v8a } */
+
+#include "../aarch64/sync-op-release.x"
+
+/* { dg-final { scan-assembler-times "stl" 1 } } */
-- 
1.9.1

Re: [PATCH 4/4][ARM][PR target/65697][5.1] Fix tests for __sync_builtins.

[Matthew Wahab]

[-- Attachment #1: Type: text/plain, Size: 1067 bytes --]

Ping. Updated patch attached.

Also, retested for arm-none-linux-gnueabihf with native bootstrap and make
check and for arm-none-eabi with cross compiled make check.

On 02/07/15 14:18, Matthew Wahab wrote:
> This patch backports fixes for the __sync builtin tests.
>
> The trunk patch submission is at
> https://gcc.gnu.org/ml/gcc-patches/2015-07/msg00031.html
> The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-07/msg00025.html
>
> Tested the series for arm-none-linux-gnueabihf with check-gcc
>
> Ok for the branch?
> Matthew
>
> gcc/testsuite
> 2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>
>
>      Backport from trunk:
>      2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>
>
>      * gcc.target/arm/armv8-sync-comp-swap.c: Replace
>      'do-require-effective-target' with 'dg-require-effective-target'.
>      * gcc.target/arm/armv8-sync-op-full.c: Likewise.
>      * gcc.target/arm/armv8-sync-op-release.c: Likewise.
>      * gcc.target/arm/armv8-sync-op-acquire.c: Likewise.  Also, replace
>      'stlex' with 'strex' as the expected output.
>


[-- Attachment #2: 0004-2015-07-01-Matthew-Wahab-matthew.wahab-arm.com.patch --]
[-- Type: text/x-patch, Size: 3290 bytes --]

From d058686fe1027927a5fdfbb81a83526e3f9b9d6d Mon Sep 17 00:00:00 2001
From: mwahab <mwahab@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Wed, 1 Jul 2015 12:16:01 +0000
Subject: [PATCH 4/4] 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>

	Backport
	* gcc.target/arm/armv8-sync-comp-swap.c: Replace
	'do-require-effective-target' with 'dg-require-effective-target'.
	* gcc.target/arm/armv8-sync-op-full.c: Likewise.
	* gcc.target/arm/armv8-sync-op-release.c: Likewise.
	* gcc.target/arm/armv8-sync-op-acquire.c: Likewise.  Also, replace
        'stlex' with 'strex' as the expected output.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225241 138bc75d-0d04-0410-961f-82ee72b054a4

Conflicts:
	gcc/testsuite/ChangeLog

Change-Id: I19f2013f7bdd2dd035f36f0f7c9829cf6a86fb8e
---
 gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c  | 2 +-
 gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c | 4 ++--
 gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c    | 2 +-
 gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c b/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
index f96c81a..0e95986 100644
--- a/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-require-effective-target arm_arch_v8a_ok } */
 /* { dg-options "-O2" } */
 /* { dg-add-options arm_arch_v8a } */
 
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
index 8d6659b..c448599 100644
--- a/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
@@ -1,10 +1,10 @@
 /* { dg-do compile } */
-/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-require-effective-target arm_arch_v8a_ok } */
 /* { dg-options "-O2" } */
 /* { dg-add-options arm_arch_v8a } */
 
 #include "../aarch64/sync-op-acquire.x"
 
 /* { dg-final { scan-assembler-times "ldrex" 1 } } */
-/* { dg-final { scan-assembler-times "stlex" 1 } } */
+/* { dg-final { scan-assembler-times "strex" 1 } } */
 /* { dg-final { scan-assembler-times "dmb" 1 } } */
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
index a5ad3bd..cce9e00 100644
--- a/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-require-effective-target arm_arch_v8a_ok } */
 /* { dg-options "-O2" } */
 /* { dg-add-options arm_arch_v8a } */
 
diff --git a/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c b/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
index 0d3be7b..502a266 100644
--- a/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
+++ b/gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { do-require-effective-target arm_arch_v8a_ok } */
+/* { dg-require-effective-target arm_arch_v8a_ok } */
 /* { dg-options "-O2" } */
 /* { dg-add-options arm_arch_v8a } */
 
-- 
1.9.1

Re: [PATCH 1/4][ARM][PR target/65697][5.1] Backport stronger barriers for __sync fetch-op builtins.

[Ramana Radhakrishnan]

On 27/07/15 11:29, Matthew Wahab wrote:
> Ping. Updated patch attached.
> 
> Also, retested for arm-none-linux-gnueabihf with native bootstrap and make
> check and for arm-none-eabi with cross compiled make check.
> 
> On 02/07/15 14:12, Matthew Wahab wrote:
>> The __sync builtins are implemented using barriers that are too weak for ARMv8
>> targets, this has been fixed on trunk for the ARM back-end. Since GCC-5.1 is
>> also generating the incorrect code, it should also be fixed.
>>
>> This patch backports the changes made to strengthen the barriers emitted for
>> the __sync fetch-and-op/op-and-fetch builtins.
>>
>> The trunk patch submission is at
>> https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01410.html
>> The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01235.html
>>
>> Tested the series for arm-none-linux-gnueabihf with check-gcc
>>
>> Ok for the branch?
>> Matthew
>>
>> 2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>
>>
>>      Backport from trunk:
>>      2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>
>>
>>      PR target/65697
>>      * config/armc/arm.c (arm_split_atomic_op): For ARMv8, replace an
>>      initial acquire barrier with final barrier.
> 

This is OK thanks,

Ramana

Re: [PATCH 2/4][ARM][PR target/65697][5.1] Backport stronger barriers for __sync,compare-and-swap builtins.

[Ramana Radhakrishnan]

On 27/07/15 11:31, Matthew Wahab wrote:
> Ping. Updated patch attached.
> 
> Also, retested for arm-none-linux-gnueabihf with native bootstrap and make
> check and for arm-none-eabi with cross compiled make check.
> 
> 
> On 02/07/15 14:15, Matthew Wahab wrote:
>> This patch backports the changes made to strengthen the barriers emitted for
>> the __sync compare-and-swap builtins.
>>
>> The trunk patch submission is at
>> https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01411.html
>> The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01236.html
>>
>> Tested the series for arm-none-linux-gnueabihf with check-gcc
>>
>> Ok for the branch?
>> Matthew
>>
>> 2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>
>>
>>      Backport from trunk:
>>      2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>
>>
>>      PR target/65697
>>      * config/armc/arm.c (arm_split_compare_and_swap): For ARMv8,
>>      replace an initial acquire barrier with final barrier.
>>
> 

OK - minor changelog nit in this and the previous patch.

s/armc/arm



Ramana

Re: [PATCH 3/4][ARM][PR target/65697][5.1] Add tests for __sync_builtins.

[Ramana Radhakrishnan]

On 27/07/15 11:31, Matthew Wahab wrote:
> Ping. Updated patch attached.
> 
> Also, retested for arm-none-linux-gnueabihf with native bootstrap and make
> check and for arm-none-eabi with cross compiled make check.
> 
> On 02/07/15 14:17, Matthew Wahab wrote:
>> This patch backports the tests added for code generated by the ARM back-end for
>> the __sync builtins.
>>
>> The trunk patch submission is at
>> https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01412.html
>> The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-06/msg01237.html
>>
>> Tested the series for arm-none-linux-gnueabihf with check-gcc
>>
>> Ok for the branch?
>> Matthew
>>
>> gcc/testsuite
>> 2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>
>>
>>      Backport from trunk:
>>      2015-06-29  Matthew Wahab  <matthew.wahab@arm.com>
>>
>>      PR target/65697
>>      * gcc.target/arm/armv-sync-comp-swap.c: New.
>>      * gcc.target/arm/armv-sync-op-acquire.c: New.
>>      * gcc.target/arm/armv-sync-op-full.c: New.
>>      * gcc.target/arm/armv-sync-op-release.c: New.
>>
> 

OK

Ramana

Re: [PATCH 4/4][ARM][PR target/65697][5.1] Fix tests for __sync_builtins.

[Ramana Radhakrishnan]

On 27/07/15 11:32, Matthew Wahab wrote:
> Ping. Updated patch attached.
> 
> Also, retested for arm-none-linux-gnueabihf with native bootstrap and make
> check and for arm-none-eabi with cross compiled make check.
> 
> On 02/07/15 14:18, Matthew Wahab wrote:
>> This patch backports fixes for the __sync builtin tests.
>>
>> The trunk patch submission is at
>> https://gcc.gnu.org/ml/gcc-patches/2015-07/msg00031.html
>> The commit is at https://gcc.gnu.org/ml/gcc-cvs/2015-07/msg00025.html
>>
>> Tested the series for arm-none-linux-gnueabihf with check-gcc
>>
>> Ok for the branch?
>> Matthew
>>
>> gcc/testsuite
>> 2015-07-02  Matthew Wahab  <matthew.wahab@arm.com>
>>
>>      Backport from trunk:
>>      2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>
>>
>>      * gcc.target/arm/armv8-sync-comp-swap.c: Replace
>>      'do-require-effective-target' with 'dg-require-effective-target'.
>>      * gcc.target/arm/armv8-sync-op-full.c: Likewise.
>>      * gcc.target/arm/armv8-sync-op-release.c: Likewise.
>>      * gcc.target/arm/armv8-sync-op-acquire.c: Likewise.  Also, replace
>>      'stlex' with 'strex' as the expected output.
>>
> 


Please mention the PR in the changelog for this and the previous patch.

OK with that change.

Ramana