On 5/21/20 12:11 PM, Richard Sandiford wrote:
Yeah, agree it'd be worth having tests for both directions. The patch
itself looks good though -- thanks for doing this.
Thanks. There's a version with 2 new tests that I've just tested.
I'm going to install the patch for master. Is it also fine for all
active branches where you backported the atomics outlining?
Martin
>From 357a86fbf18ad511a72e6e9c703a6e0b0dd30ddf Mon Sep 17 00:00:00 2001
From: Martin Liska <mli...@suse.cz>
Date: Thu, 21 May 2020 09:19:21 +0200
Subject: [PATCH] Add outline-atomics to target attribute.
gcc/ChangeLog:
2020-05-21 Martin Liska <mli...@suse.cz>
* common/config/aarch64/aarch64-common.c (aarch64_handle_option):
Handle OPT_moutline_atomics.
* config/aarch64/aarch64.c: Add outline-atomics to
aarch64_attributes.
* doc/extend.texi: Document the newly added target attribute.
gcc/testsuite/ChangeLog:
2020-05-21 Martin Liska <mli...@suse.cz>
* gcc.target/aarch64/target_attr_20.c: New test.
* gcc.target/aarch64/target_attr_21.c: New test.
---
gcc/common/config/aarch64/aarch64-common.c | 4 +++
gcc/config/aarch64/aarch64.c | 2 ++
gcc/doc/extend.texi | 6 +++++
.../gcc.target/aarch64/target_attr_20.c | 27 +++++++++++++++++++
.../gcc.target/aarch64/target_attr_21.c | 27 +++++++++++++++++++
5 files changed, 66 insertions(+)
create mode 100644 gcc/testsuite/gcc.target/aarch64/target_attr_20.c
create mode 100644 gcc/testsuite/gcc.target/aarch64/target_attr_21.c
diff --git a/gcc/common/config/aarch64/aarch64-common.c b/gcc/common/config/aarch64/aarch64-common.c
index 0bddcc8c3e9..51bd319d6d3 100644
--- a/gcc/common/config/aarch64/aarch64-common.c
+++ b/gcc/common/config/aarch64/aarch64-common.c
@@ -116,6 +116,10 @@ aarch64_handle_option (struct gcc_options *opts,
opts->x_flag_omit_leaf_frame_pointer = val;
return true;
+ case OPT_moutline_atomics:
+ opts->x_aarch64_flag_outline_atomics = val;
+ return true;
+
default:
return true;
}
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 79c016f4dc3..78db0a56323 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -15266,6 +15266,8 @@ static const struct aarch64_attribute_info aarch64_attributes[] =
aarch64_handle_attr_branch_protection, OPT_mbranch_protection_ },
{ "sign-return-address", aarch64_attr_enum, false, NULL,
OPT_msign_return_address_ },
+ { "outline-atomics", aarch64_attr_bool, true, NULL,
+ OPT_moutline_atomics},
{ NULL, aarch64_attr_custom, false, NULL, OPT____ }
};
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index c80848e9061..a2ebef8cf8c 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -4066,6 +4066,12 @@ Select the function scope on which branch protection will be applied. The
behavior and permissible arguments are the same as for the command-line option
@option{-mbranch-protection=}. The default value is @code{none}.
+@item outline-atomics
+@cindex @code{outline-atomics} function attribute, AArch64
+Enable or disable calls to out-of-line helpers to implement atomic operations.
+This corresponds to the behavior of the command line options
+@option{-moutline-atomics} and @option{-mno-outline-atomics}.
+
@end table
The above target attributes can be specified as follows:
diff --git a/gcc/testsuite/gcc.target/aarch64/target_attr_20.c b/gcc/testsuite/gcc.target/aarch64/target_attr_20.c
new file mode 100644
index 00000000000..509fb039e84
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/target_attr_20.c
@@ -0,0 +1,27 @@
+/* { dg-do compile } */
+/* { dg-options "-march=armv8-a+nolse -moutline-atomics" } */
+
+int b, c, d, e, f, h;
+short g;
+int foo (int) __attribute__ ((__const__));
+
+__attribute__ ((target ("no-outline-atomics")))
+void
+bar (void)
+{
+ while (1)
+ {
+ while (1)
+ {
+ __atomic_load_n (&e, 0);
+ if (foo (2))
+ __sync_val_compare_and_swap (&c, 0, f);
+ b = 1;
+ if (h == e)
+ break;
+ }
+ __sync_val_compare_and_swap (&g, -1, f);
+ }
+}
+
+/* { dg-final { scan-assembler-not "bl.*__aarch64_cas2_acq_rel" } } */
diff --git a/gcc/testsuite/gcc.target/aarch64/target_attr_21.c b/gcc/testsuite/gcc.target/aarch64/target_attr_21.c
new file mode 100644
index 00000000000..acace4c8f2a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/target_attr_21.c
@@ -0,0 +1,27 @@
+/* { dg-do compile } */
+/* { dg-options "-march=armv8-a+nolse -mno-outline-atomics" } */
+
+int b, c, d, e, f, h;
+short g;
+int foo (int) __attribute__ ((__const__));
+
+__attribute__ ((target ("outline-atomics")))
+void
+bar (void)
+{
+ while (1)
+ {
+ while (1)
+ {
+ __atomic_load_n (&e, 0);
+ if (foo (2))
+ __sync_val_compare_and_swap (&c, 0, f);
+ b = 1;
+ if (h == e)
+ break;
+ }
+ __sync_val_compare_and_swap (&g, -1, f);
+ }
+}
+
+/* { dg-final { scan-assembler-times "bl.*__aarch64_cas2_acq_rel" 1 } } */
--
2.26.2
