diff mbox series

[v3] bpf: Add support to eBPF atomic instructions

Message ID 20211026120656.157544-1-guillermo.e.martinez@oracle.com
State New
Headers
Series [v3] bpf: Add support to eBPF atomic instructions |

Commit Message

Guillermo E. Martinez Oct. 26, 2021, 12:06 p.m. UTC 
  Hello people,

This patch v3 to add support for atomics instructions in eBPF target,
the rtl for eBPF atomics was splitted in a new file: atomic.md,

Thanks Andrew for the comments,

Kind Regards,
Guillermo

    eBPF add support for atomic instructions, the following
    gcc built-in functions are implemented for bpf target using
    both: 32 and 64 bits data types:

     __atomic_fetch_add
     __atomic_fetch_sub
     __atomic_fetch_and
     __atomic_fetch_xor
     __atomic_fetch_or
     __atomic_exchange
     __atomic_compare_exchange_n

    Also calls to __atomic_<instruction>_fetch are fully supported.

    New define instructions were added to bpf.md along with its
    tests for gcc atomic built-in functions.

    In order to restrict/enable the use of `add + fetch' and the
    rest of atomic instructions the -m[no-]atomics was added.

    Those instructions are fully compliant with:
      https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html
      https://www.kernel.org/doc/Documentation/networking/filter.rst

    This support depends of two previous submissions in CGEN and
    binutils-gdb projects:
       https://sourceware.org/pipermail/cgen/2021q3/002774.html
       https://sourceware.org/pipermail/binutils/2021-August/117798.html

    gcc/
      * config/bpf/bpf.md: Add defines for atomic instructions.
      * config/bpf/bpf.c: Enable atomics by default in ISA v3.
      * config/bpf/bpf.h: Pass option to gas to disabled use of
      atomics (-mno-atomics).
      * config/bpf/bpf.opt: Add -m[no-]atomics option.
      * doc/invoke.texi: Add documentation for -m[no-a]tomics.

    gcc/testsuite/
       * gcc.target/bpf/atomic-compare-exchange.c: New test.
       * gcc.target/bpf/atomic-exchange.c: Likewise.
       * gcc.target/bpf/atomic-add.c: Likewise.
       * gcc.target/bpf/atomic-and.c: Likewise.
       * gcc.target/bpf/atomic-or.c: Likewise.
       * gcc.target/bpf/atomic-sub.c: Likewise.
       * gcc.target/bpf/atomic-xor.c: Likewise.
       * gcc.target/bpf/atomics-disabled.c: Likewise.
       * gcc.target/bpf/ftest-mcpuv3-atomics.c: Likewise.
       * gcc.target/bpf/ftest-no-atomics-add.c: Likewise.
---
 gcc/ChangeLog                                 |   8 +
 gcc/config/bpf/atomic.md                      | 160 ++++++++++++++++++
 gcc/config/bpf/bpf.c                          |   2 +
 gcc/config/bpf/bpf.h                          |  12 +-
 gcc/config/bpf/bpf.md                         |  24 +--
 gcc/config/bpf/bpf.opt                        |   4 +
 gcc/config/bpf/constraints.md                 |   3 +
 gcc/doc/invoke.texi                           |  12 +-
 gcc/testsuite/ChangeLog                       |  12 ++
 .../gcc.target/bpf/atomic-add-fetch.c         |  29 ++++
 gcc/testsuite/gcc.target/bpf/atomic-and.c     |  25 +++
 .../gcc.target/bpf/atomic-compare-exchange.c  |  28 +++
 .../gcc.target/bpf/atomic-exchange.c          |  19 +++
 gcc/testsuite/gcc.target/bpf/atomic-or.c      |  25 +++
 gcc/testsuite/gcc.target/bpf/atomic-sub.c     |  27 +++
 gcc/testsuite/gcc.target/bpf/atomic-xor.c     |  25 +++
 .../gcc.target/bpf/atomics-disabled.c         |  28 +++
 .../gcc.target/bpf/ftest-mcpuv3-atomics.c     |  36 ++++
 .../gcc.target/bpf/ftest-no-atomics-add.c     |  23 +++
 19 files changed, 482 insertions(+), 20 deletions(-)
 create mode 100644 gcc/config/bpf/atomic.md
 create mode 100644 gcc/testsuite/gcc.target/bpf/atomic-add-fetch.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/atomic-and.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/atomic-compare-exchange.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/atomic-exchange.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/atomic-or.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/atomic-sub.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/atomic-xor.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/atomics-disabled.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/ftest-mcpuv3-atomics.c
 create mode 100644 gcc/testsuite/gcc.target/bpf/ftest-no-atomics-add.c
diff mbox series

Patch

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 115f32e5061..782d33908ba 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@ 
+2021-10-25  Guillermo E. Martinez  <guillermo.e.martinez@oracle.com>
+	* config/bpf/bpf.md: Add defines for atomic instructions.
+	* config/bpf/bpf.c: Enable atomics by default in ISA v3.
+	* config/bpf/bpf.h: Pass option to gas to disable use of
+	atomics (-mno-atomics).
+	* config/bpf/bpf.opt: Add -m[no-]atomics option.
+	* doc/invoke.texi: Add documentation for -m[no-]atomics.
+
 2021-10-20  Alex Coplan  <alex.coplan@arm.com>
 
 	* calls.c (initialize_argument_information): Remove some dead
diff --git a/gcc/config/bpf/atomic.md b/gcc/config/bpf/atomic.md
new file mode 100644
index 00000000000..9afc38f01ae
--- /dev/null
+++ b/gcc/config/bpf/atomic.md
@@ -0,0 +1,160 @@ 
+;; Machine description for eBPF atomic Instructions.
+;; Copyright (C) 2021 Free Software Foundation, Inc.
+
+;; This file is part of GCC.
+
+;; GCC is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 3, or (at your option)
+;; any later version.
+
+;; GCC is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GCC; see the file COPYING3.  If not see
+;; <http://www.gnu.org/licenses/>.
+
+(define_mode_iterator AMO [SI DI])
+
+(define_insn "atomic_add<AMO:mode>"
+  [(set (match_operand:AMO 0 "memory_operand" "+m")
+    (unspec_volatile:AMO
+      [(plus:AMO (match_dup 0)
+        (match_operand:AMO 1 "register_operand" "r"))
+        (match_operand:SI 2 "const_int_operand")] ;; Memory model.
+   UNSPEC_XADD))]
+  ""
+  "xadd<mop>\t%0,%1")
+
+(define_expand "atomic_fetch_add<AMO:mode>"
+  [(match_operand:AMO 0 "register_operand")
+   (match_operand:AMO 1 "memory_operand")
+   (match_operand:AMO 2 "nonmemory_operand")
+   (match_operand:AMO 3 "const_int_operand")] ;; Memory model
+  ""
+  {
+    if (bpf_has_atomics)
+      {
+        emit_insn
+          (gen_atomic_fetch_add<AMO:mode>_1
+            (operands[0], operands[1], operands[2], operands[3]));
+      }
+    else
+        error ("invalid usage of the xadd return value");
+
+    DONE;
+  })
+
+ (define_insn "atomic_fetch_add<AMO:mode>_1"
+   [(set (match_operand:AMO 0 "register_operand" "=r")
+   (unspec_volatile:AMO
+     [(match_operand:AMO 1 "memory_operand" "+o")
+      (match_operand:AMO 2 "nonmemory_operand" "0")
+      (match_operand:AMO 3 "const_int_operand")] ;; Memory model
+     UNSPEC_XADD))]
+   ""
+   "xaddf<mop>\t%1,%0")
+
+(define_insn "atomic_fetch_and<AMO:mode>"
+  [(set (match_operand:AMO 0 "register_operand" "=r")
+  (unspec_volatile:AMO
+    [(match_operand:AMO 1 "memory_operand" "+o")
+     (match_operand:AMO 2 "nonmemory_operand" "0")
+     (match_operand:AMO 3 "const_int_operand")]
+    UNSPEC_XAND))]
+  "bpf_has_atomics"
+  "xand<mop>\t%1,%0")
+
+(define_insn "atomic_fetch_or<AMO:mode>"
+  [(set (match_operand:AMO 0 "register_operand" "=r")
+  (unspec_volatile:AMO
+    [(match_operand:AMO 1 "memory_operand" "+o")
+     (match_operand:AMO 2 "nonmemory_operand" "0")
+     (match_operand:AMO 3 "const_int_operand")]
+    UNSPEC_XOR))]
+  "bpf_has_atomics"
+  "xor<mop>\t%1,%0")
+
+(define_insn "atomic_fetch_xor<AMO:mode>"
+  [(set (match_operand:AMO 0 "register_operand" "=r")
+  (unspec_volatile:AMO
+    [(match_operand:AMO 1 "memory_operand" "+o")
+     (match_operand:AMO 2 "nonmemory_operand" "0")
+     (match_operand:AMO 3 "const_int_operand")]
+    UNSPEC_XXOR))]
+  "bpf_has_atomics"
+  "xxor<mop>\t%1,%0")
+
+(define_insn "atomic_exchange<AMO:mode>"
+  [(set (match_operand:AMO 0 "register_operand" "=r")
+  (unspec_volatile:AMO
+    [(match_operand:AMO 1 "memory_operand" "+o")
+     (match_operand:AMO 2 "nonmemory_operand" "0")
+     (match_operand:AMO 3 "const_int_operand")]
+    UNSPEC_XCHG))]
+  "bpf_has_atomics"
+  "xchg<mop>\t%1,%0")
+
+;; eBPF compare and exchange operation atomically compares the
+;; value addressed by memory operand(%0) with _R0_(%1), so
+;; there is a constraint to load the expected value in mentioned
+;; register. If they match it is replaced with desired value(%3).
+;; In either case, the value that was there before in %0 is
+;; zero-extended and loaded back to R0.
+
+(define_expand "atomic_compare_and_swap<AMO:mode>"
+  [(match_operand:SI 0 "register_operand")    ;; bool success
+   (match_operand:AMO 1 "register_operand")   ;; old value
+   (match_operand:AMO 2 "memory_operand")     ;; memory
+   (match_operand:AMO 3 "register_operand")   ;; expected
+   (match_operand:AMO 4 "register_operand")   ;; desired
+   (match_operand:SI 5 "const_int_operand")   ;; is_weak (unused)
+   (match_operand:SI 6 "const_int_operand")   ;; success model (unused)
+   (match_operand:SI 7 "const_int_operand")]  ;; failure model (unused)
+  ""
+{
+  if (bpf_has_atomics)
+    {
+      emit_insn
+        (gen_atomic_compare_and_swap<AMO:mode>_1
+          (operands[1], operands[2], operands[3], operands[4], operands[6]));
+
+      /* Assume success operation, i.e memory operand
+         is matched with expected value.
+       */
+      emit_move_insn (operands[0], const1_rtx);
+      rtx_code_label *success_label = gen_label_rtx ();
+
+      /* At this point eBPF xcmp was executed, now we can ask
+       * for success exchange, and set suitable value for bool
+       * operand(%0)
+       */
+      emit_cmp_and_jump_insns (operands[1], operands[3], EQ, 0,
+                               GET_MODE (operands[1]), 1, success_label);
+      emit_move_insn (operands[0], const0_rtx);
+
+      if (success_label)
+        {
+           emit_label (success_label);
+           LABEL_NUSES (success_label) = 1;
+        }
+      }
+      else
+        error ("unsupported atomic instruction");
+
+  DONE;
+})
+
+(define_insn "atomic_compare_and_swap<AMO:mode>_1"
+  [(set (match_operand:AMO 0 "register_operand" "=t") ;; must be r0
+  (unspec_volatile:AMO
+    [(match_operand:AMO 1 "memory_operand" "+o")  ;; memory
+     (match_operand:AMO 2 "register_operand" "0") ;; expected
+     (match_operand:AMO 3 "register_operand" "r") ;; desired
+     (match_operand:SI 4 "const_int_operand")]    ;; success (unused)
+    UNSPEC_CMPXCHG))]
+  "bpf_has_atomics"
+  "xcmp<mop>\t%1,%3")
diff --git a/gcc/config/bpf/bpf.c b/gcc/config/bpf/bpf.c
index 82bb698bd91..5f489c829cc 100644
--- a/gcc/config/bpf/bpf.c
+++ b/gcc/config/bpf/bpf.c
@@ -253,6 +253,8 @@  bpf_option_override (void)
   if (bpf_has_jmp32 == -1)
     bpf_has_jmp32 = (bpf_isa >= ISA_V3);
 
+  if (bpf_has_atomics == -1)
+    bpf_has_atomics = (bpf_isa >= ISA_V3);
 }
 
 #undef TARGET_OPTION_OVERRIDE
diff --git a/gcc/config/bpf/bpf.h b/gcc/config/bpf/bpf.h
index 82be0c3e190..d886e7e98ce 100644
--- a/gcc/config/bpf/bpf.h
+++ b/gcc/config/bpf/bpf.h
@@ -22,7 +22,9 @@ 
 
 /**** Controlling the Compilation Driver.  */
 
-#define ASM_SPEC "%{mbig-endian:-EB} %{!mbig-endian:-EL} %{mxbpf:-mxbpf}"
+#define ASM_SPEC \
+  "%{mbig-endian:-EB} %{!mbig-endian:-EL} %{mxbpf:-mxbpf} " \
+  "%{mno-atomics:-mno-atomics} "
 #define LINK_SPEC "%{mbig-endian:-EB} %{!mbig-endian:-EL}"
 #define LIB_SPEC ""
 #define STARTFILE_SPEC ""
@@ -176,6 +178,7 @@ 
 enum reg_class
 {
   NO_REGS,		/* no registers in set.  */
+  R0,		        /* register r0.  */
   ALL_REGS,		/* all registers.  */
   LIM_REG_CLASSES	/* max value + 1.  */
 };
@@ -189,6 +192,7 @@  enum reg_class
 #define REG_CLASS_NAMES				\
 {						\
   "NO_REGS",					\
+  "R0",					\
   "ALL_REGS"					\
 }
 
@@ -202,14 +206,16 @@  enum reg_class
 #define REG_CLASS_CONTENTS			\
 {						\
    0x00000000, /* NO_REGS */			\
-   0x00000fff, /* ALL_REGS */		        \
+   0x00000001, /* R0 */		        \
+   0x00000fff, /* ALL_REGS */		  \
 }
 
 /* A C expression whose value is a register class containing hard
    register REGNO.  In general there is more that one such class;
    choose a class which is "minimal", meaning that no smaller class
    also contains the register.  */
-#define REGNO_REG_CLASS(REGNO) GENERAL_REGS
+#define REGNO_REG_CLASS(REGNO)          \
+  ((REGNO) == 0 ? R0 : GENERAL_REGS)
 
 /* A macro whose definition is the name of the class to which a
    valid base register must belong.  A base register is one used in
diff --git a/gcc/config/bpf/bpf.md b/gcc/config/bpf/bpf.md
index 436c8dfa059..97b1b02313d 100644
--- a/gcc/config/bpf/bpf.md
+++ b/gcc/config/bpf/bpf.md
@@ -25,6 +25,11 @@ 
 (define_c_enum "unspec" [
   UNSPEC_LDINDABS
   UNSPEC_XADD
+  UNSPEC_XAND
+  UNSPEC_XOR
+  UNSPEC_XXOR
+  UNSPEC_XCHG
+  UNSPEC_CMPXCHG
 ])
 
 ;;;; Constants
@@ -56,11 +61,10 @@ 
 ;; st		generic store instructions for immediates.
 ;; stx		generic store instructions.
 ;; jmp		jump instructions.
-;; xadd		atomic exchange-and-add instructions.
 ;; multi	multiword sequence (or user asm statements).
 
 (define_attr "type"
-  "unknown,alu,alu32,end,ld,lddw,ldx,st,stx,jmp,xadd,multi"
+  "unknown,alu,alu32,end,ld,lddw,ldx,st,stx,jmp,multi"
   (const_string "unknown"))
 
 ;; Length of instruction in bytes.
@@ -512,17 +516,5 @@ 
   "ldabs<ldop>\t%0"
   [(set_attr "type" "ld")])
 
-;;;; Atomic increments
-
-(define_mode_iterator AMO [SI DI])
-
-(define_insn "atomic_add<AMO:mode>"
-  [(set (match_operand:AMO 0 "memory_operand" "+m")
-        (unspec_volatile:AMO
-         [(plus:AMO (match_dup 0)
-                    (match_operand:AMO 1 "register_operand" "r"))
-          (match_operand:SI 2 "const_int_operand")] ;; Memory model.
-         UNSPEC_XADD))]
-  ""
-  "xadd<mop>\t%0,%1"
-  [(set_attr "type" "xadd")])
+;; include atomic instructions
+(include "atomic.md")
diff --git a/gcc/config/bpf/bpf.opt b/gcc/config/bpf/bpf.opt
index e8b728ca69f..3eea3a75b62 100644
--- a/gcc/config/bpf/bpf.opt
+++ b/gcc/config/bpf/bpf.opt
@@ -146,6 +146,10 @@  mjmp32
 Target Var(bpf_has_jmp32) Init(-1)
 Enable 32-bit jump instructions.
 
+matomics
+Target Var(bpf_has_atomics) Init(-1)
+Enable eBPF atomic instructions.
+
 mcpu=
 Target RejectNegative Joined Var(bpf_isa) Enum(bpf_isa) Init(ISA_V3)
 
diff --git a/gcc/config/bpf/constraints.md b/gcc/config/bpf/constraints.md
index 66b7764d775..9606b6e150e 100644
--- a/gcc/config/bpf/constraints.md
+++ b/gcc/config/bpf/constraints.md
@@ -29,3 +29,6 @@ 
 (define_constraint "S"
   "A constant call address."
   (match_code "const,symbol_ref,label_ref,const_int"))
+
+(define_register_constraint "t" "R0"
+  "Register r0")
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 6d1e328571a..136a1e87fec 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -905,7 +905,7 @@  Objective-C and Objective-C++ Dialects}.
 
 @emph{eBPF Options}
 @gccoptlist{-mbig-endian -mlittle-endian -mkernel=@var{version}
--mframe-limit=@var{bytes} -mxbpf -mco-re -mno-co-re
+-mframe-limit=@var{bytes} -mxbpf -mco-re -mno-co-re -matomics
 -mjmpext -mjmp32 -malu32 -mcpu=@var{version}}
 
 @emph{FR30 Options}
@@ -22824,6 +22824,7 @@  All features of v2, plus:
 @itemize @minus
 @item 32-bit jump operations, as in @option{-mjmp32}
 @item 32-bit ALU operations, as in @option{-malu32}
+@item Atomics instructions
 @end itemize
 
 @end table
@@ -22846,6 +22847,15 @@  the restrictions imposed by the BPF architecture:
 @item Save and restore callee-saved registers at function entry and
 exit, respectively.
 @end itemize
+
+@item -matomics
+Enable use of eBPF atomic instructions. This is set by default when
+eBPF ISA is greater or equal to @samp{v3}. If this option is set,
+then  GCC for eBPF can emit a full set of atomic instructions, those
+atomics may not be executed by all kernel versions. This option is not
+enabled by default when eBPF ISA is lower than @samp{v3}, so atomics are
+disabled with the exception of @samp{add} instruction, allowing
+backward compatibility in older kernel versions.
 @end table
 
 @node FR30 Options
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 602b727f1a5..10ac40d88be 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,15 @@ 
+2021-10-25  Guillermo E. Martinez  <guillermo.e.martinez@oracle.com>
+	* gcc.target/bpf/atomic-compare-exchange.c: New test.
+	* gcc.target/bpf/atomic-exchange.c: Likewise.
+	* gcc.target/bpf/atomic-add.c: Likewise.
+	* gcc.target/bpf/atomic-and.c: Likewise.
+	* gcc.target/bpf/atomic-or.c: Likewise.
+	* gcc.target/bpf/atomic-sub.c: Likewise.
+	* gcc.target/bpf/atomic-xor.c: Likewise.
+	* gcc.target/bpf/atomics-disabled.c: Likewise.
+	* gcc.target/bpf/ftest-mcpuv3-atomics.c: Likewise.
+	* gcc.target/bpf/ftest-no-atomics-add.c: Likewise.
+
 2021-10-20  Tamar Christina  <tamar.christina@arm.com>
 
 	* gcc.target/aarch64/mvn-cmeq0-1.c: New test.
diff --git a/gcc/testsuite/gcc.target/bpf/atomic-add-fetch.c b/gcc/testsuite/gcc.target/bpf/atomic-add-fetch.c
new file mode 100644
index 00000000000..047a0688b00
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/atomic-add-fetch.c
@@ -0,0 +1,29 @@ 
+/* { dg-do compile } */
+
+long delta;
+long *val;
+
+/*
+ * fetch atomic add is only available with -matomics or
+ * -mcpu=v3 option.
+ */
+void
+foo ()
+{
+  volatile long k;
+
+  k = __atomic_fetch_add (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_fetch_add ((int*)val, delta, __ATOMIC_RELAXED);
+
+  k = __atomic_add_fetch (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_add_fetch ((int*)val, delta, __ATOMIC_RELAXED);
+
+  k = __sync_fetch_and_add (val, delta, __ATOMIC_RELAXED);
+  k = __sync_fetch_and_add ((int*)val, delta, __ATOMIC_RELAXED);
+
+  k = __sync_add_and_fetch (val, delta, __ATOMIC_RELAXED);
+  k = __sync_add_and_fetch ((int*)val, delta, __ATOMIC_RELAXED);
+}
+
+/* { dg-final { scan-assembler "xaddfdw\t.*" } } */
+/* { dg-final { scan-assembler "xaddfw\t.*" } } */
diff --git a/gcc/testsuite/gcc.target/bpf/atomic-and.c b/gcc/testsuite/gcc.target/bpf/atomic-and.c
new file mode 100644
index 00000000000..6cc05a824f6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/atomic-and.c
@@ -0,0 +1,25 @@ 
+/* { dg-do compile } */
+
+long mask;
+long *val;
+
+void
+foo ()
+{
+  long k;
+
+  k = __atomic_fetch_and (val, mask, __ATOMIC_RELAXED);
+  k = __atomic_fetch_and ((int*)val, mask, __ATOMIC_RELAXED);
+
+  k = __atomic_and_fetch (val, mask, __ATOMIC_RELAXED);
+  k = __atomic_and_fetch ((int*)val, mask, __ATOMIC_RELAXED);
+
+  k = __sync_fetch_and_and (val, mask, __ATOMIC_RELAXED);
+  k = __sync_fetch_and_and ((int*)val, mask, __ATOMIC_RELAXED);
+
+  k = __sync_and_and_fetch (val, mask, __ATOMIC_RELAXED);
+  k = __sync_and_and_fetch ((int*)val, mask, __ATOMIC_RELAXED);
+}
+
+/* { dg-final { scan-assembler "xanddw\t.*" } } */
+/* { dg-final { scan-assembler "xandw\t.*" } } */
diff --git a/gcc/testsuite/gcc.target/bpf/atomic-compare-exchange.c b/gcc/testsuite/gcc.target/bpf/atomic-compare-exchange.c
new file mode 100644
index 00000000000..d522697ec9e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/atomic-compare-exchange.c
@@ -0,0 +1,28 @@ 
+/* { dg-do compile } */
+
+long val;
+long ptr;
+long expected;
+long desired;
+
+void
+foo ()
+{
+  int done;
+
+  done = __atomic_compare_exchange_n (&ptr, &expected, desired,
+                  0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+  done = __atomic_compare_exchange_n ((int *)&ptr, (int *)&expected,
+                  (int)desired, 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+
+  done = __atomic_compare_exchange (&ptr, &expected, &desired,
+                  0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+  done = __atomic_compare_exchange ((int *)&ptr, (int *)&expected,
+                  (int *)&desired, 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+
+  done = __sync_bool_compare_and_swap (&ptr, expected, desired);
+  done = __sync_bool_compare_and_swap ((int*)&ptr, expected, desired);
+}
+
+/* { dg-final { scan-assembler "xcmpdw\t.*" } } */
+/* { dg-final { scan-assembler "xcmpw\t.*" } } */
diff --git a/gcc/testsuite/gcc.target/bpf/atomic-exchange.c b/gcc/testsuite/gcc.target/bpf/atomic-exchange.c
new file mode 100644
index 00000000000..f4e60568f7f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/atomic-exchange.c
@@ -0,0 +1,19 @@ 
+/* { dg-do compile } */
+
+long val;
+long ptr;
+
+void
+foo ()
+{
+  long prev;
+
+  __atomic_exchange(&ptr, &val, &prev, __ATOMIC_RELAXED);
+  prev = __atomic_exchange_n(&ptr, val, __ATOMIC_RELAXED);
+
+  __atomic_exchange((int *)&ptr, (int *)&val, (int *)&prev, __ATOMIC_RELAXED);
+  prev = __atomic_exchange_n((int *)&ptr, (int)val, __ATOMIC_RELAXED);
+}
+
+/* { dg-final { scan-assembler "xchgdw\t.*" } } */
+/* { dg-final { scan-assembler "xchgw\t.*" } } */
diff --git a/gcc/testsuite/gcc.target/bpf/atomic-or.c b/gcc/testsuite/gcc.target/bpf/atomic-or.c
new file mode 100644
index 00000000000..af9a999e02a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/atomic-or.c
@@ -0,0 +1,25 @@ 
+/* { dg-do compile } */
+
+long bits;
+long *val;
+
+void
+foo ()
+{
+  long k;
+
+  k = __atomic_fetch_or (val, bits, __ATOMIC_RELAXED);
+  k = __atomic_fetch_or ((int *)val, bits, __ATOMIC_RELAXED);
+
+  k = __atomic_or_fetch (val, bits, __ATOMIC_RELAXED);
+  k = __atomic_or_fetch ((int*)val, bits, __ATOMIC_RELAXED);
+
+  k = __sync_fetch_and_or (val, bits, __ATOMIC_RELAXED);
+  k = __sync_fetch_and_or ((int*)val, bits, __ATOMIC_RELAXED);
+
+  k = __sync_or_and_fetch (val, bits, __ATOMIC_RELAXED);
+  k = __sync_or_and_fetch ((int*)val, bits, __ATOMIC_RELAXED);
+}
+
+/* { dg-final { scan-assembler "xordw\t.*" } } */
+/* { dg-final { scan-assembler "xorw\t.*" } } */
diff --git a/gcc/testsuite/gcc.target/bpf/atomic-sub.c b/gcc/testsuite/gcc.target/bpf/atomic-sub.c
new file mode 100644
index 00000000000..92b95f6f368
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/atomic-sub.c
@@ -0,0 +1,27 @@ 
+/* { dg-do compile } */
+
+long delta;
+long *val;
+
+void
+foo ()
+{
+  volatile long k;
+
+  k = __atomic_fetch_sub (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_fetch_sub ((int*)val, delta, __ATOMIC_RELAXED);
+
+  k = __atomic_sub_fetch (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_sub_fetch ((int*)val, delta, __ATOMIC_RELAXED);
+
+  __sync_fetch_and_sub (val, delta, __ATOMIC_RELAXED);
+  __sync_fetch_and_sub ((int*)val, delta, __ATOMIC_RELAXED);
+
+  k = __sync_sub_and_fetch (val, delta, __ATOMIC_RELAXED);
+  k = __sync_sub_and_fetch ((int*)val, delta, __ATOMIC_RELAXED);
+}
+
+/* { dg-final { scan-assembler "xadddw\t.*" } } */
+/* { dg-final { scan-assembler "xaddw\t.*" } } */
+/* { dg-final { scan-assembler "xaddfdw\t.*" } } */
+/* { dg-final { scan-assembler "xaddfw\t.*" } } */
diff --git a/gcc/testsuite/gcc.target/bpf/atomic-xor.c b/gcc/testsuite/gcc.target/bpf/atomic-xor.c
new file mode 100644
index 00000000000..433600395a6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/atomic-xor.c
@@ -0,0 +1,25 @@ 
+/* { dg-do compile } */
+
+long bits;
+long *val;
+
+void
+foo ()
+{
+  long k;
+
+  k = __atomic_fetch_xor (val, bits, __ATOMIC_RELAXED);
+  k = __atomic_fetch_xor ((int *)val, bits, __ATOMIC_RELAXED);
+
+  k = __atomic_xor_fetch (val, bits, __ATOMIC_RELAXED);
+  k = __atomic_xor_fetch ((int*)val, bits, __ATOMIC_RELAXED);
+
+  k = __sync_fetch_and_xor (val, bits, __ATOMIC_RELAXED);
+  k = __sync_fetch_and_xor ((int*)val, bits, __ATOMIC_RELAXED);
+
+  k = __sync_xor_and_fetch (val, bits, __ATOMIC_RELAXED);
+  k = __sync_xor_and_fetch ((int*)val, bits, __ATOMIC_RELAXED);
+}
+
+/* { dg-final { scan-assembler "xxordw\t.*" } } */
+/* { dg-final { scan-assembler "xxorw\t.*" } } */
diff --git a/gcc/testsuite/gcc.target/bpf/atomics-disabled.c b/gcc/testsuite/gcc.target/bpf/atomics-disabled.c
new file mode 100644
index 00000000000..b2bf040a35c
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/atomics-disabled.c
@@ -0,0 +1,28 @@ 
+/* { dg-do compile } */
+/* { dg-options "-mcpu=v2" } */
+/* { dg-xfail-if "" { bpf-*-* } } */
+
+long delta;
+long bits;
+long *val;
+long ptr;
+
+/* Atomic instructions are disabled when eBPF ISA version
+ * is lower than v3 or -mno-atomics is set.
+ */
+
+void
+foo ()
+{
+  volatile long k;
+
+  __atomic_fetch_add (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_fetch_add (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_fetch_and ((int*)val, delta, __ATOMIC_RELAXED);
+
+  __atomic_compare_exchange_n (&ptr, &delta, bits, 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+  __atomic_exchange(&ptr, &val, &delta, __ATOMIC_RELAXED);
+
+  k = __atomic_fetch_or (val, bits, __ATOMIC_RELAXED);
+  k = __atomic_fetch_xor (val, bits, __ATOMIC_RELAXED);
+}
diff --git a/gcc/testsuite/gcc.target/bpf/ftest-mcpuv3-atomics.c b/gcc/testsuite/gcc.target/bpf/ftest-mcpuv3-atomics.c
new file mode 100644
index 00000000000..4258c8fa300
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/ftest-mcpuv3-atomics.c
@@ -0,0 +1,36 @@ 
+/* { dg-do compile } */
+/* { dg-options "-mcpu=v3" } */
+
+long delta;
+long bits;
+long *val;
+long ptr;
+
+/* Atomic instructions are enabled by default in eBPF ISA v3,
+ * but those instructions can be removed from ISA v3 adding
+ * -mno-atomics option.
+ */
+
+void
+foo ()
+{
+  volatile long k;
+
+  __atomic_fetch_add (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_fetch_add (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_fetch_and ((int*)val, delta, __ATOMIC_RELAXED);
+
+  __atomic_compare_exchange_n (&ptr, &delta, bits, 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+  __atomic_exchange(&ptr, &val, &delta, __ATOMIC_RELAXED);
+
+  k = __atomic_fetch_or (val, bits, __ATOMIC_RELAXED);
+  k = __atomic_fetch_xor (val, bits, __ATOMIC_RELAXED);
+}
+
+/* { dg-final { scan-assembler "xadddw\t.*" } } */
+/* { dg-final { scan-assembler "xaddfdw\t.*" } } */
+/* { dg-final { scan-assembler "xandw\t.*" } } */
+/* { dg-final { scan-assembler "xcmpdw\t.*" } } */
+/* { dg-final { scan-assembler "xchgdw\t.*" } } */
+/* { dg-final { scan-assembler "xordw\t.*" } } */
+/* { dg-final { scan-assembler "xxordw\t.*" } } */
diff --git a/gcc/testsuite/gcc.target/bpf/ftest-no-atomics-add.c b/gcc/testsuite/gcc.target/bpf/ftest-no-atomics-add.c
new file mode 100644
index 00000000000..6cef3bc3bc7
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/ftest-no-atomics-add.c
@@ -0,0 +1,23 @@ 
+/* { dg-do compile } */
+/* { dg-options "-mno-atomics" } */
+/* { dg-xfail-if "" { bpf-*-* } } */
+
+long delta;
+long *val;
+
+/* Assignment of the return value for xadd instruction
+ * is not allowed when atomic instructions are disabled:
+ * -mno-atomics or mcpu=v{1|2}.
+ */
+
+void
+foo ()
+{
+  volatile long k;
+
+  k = __atomic_fetch_add (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_fetch_add ((int*)val, delta, __ATOMIC_RELAXED);
+
+  k = __atomic_add_fetch (val, delta, __ATOMIC_RELAXED);
+  k = __atomic_add_fetch ((int*)val, delta, __ATOMIC_RELAXED);
+}