The Aarch64 backend implements the atomic operations on memory with the same
patterns iterated over logical and arithmetic operation. It also specifies
constraints on an operand for the operations but the constraints used are only
valid for the logical operations. This can lead to an ICE, with the compiler
unable to generate a valid instruction.
This patch reworks the atomic operation patterns to select the
appropriate constraint for the operation. The logical operations take
the constraints specified by the current lconst_atomic mode iterator
while the arithmetic operations (plus, sub) take constraint "I".
This patch also adds the test-case provided by Matthia Klose for the bugzilla
entry https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67143, slightly modified to
compile as plain C.
Tested for arm-none-eabi with cross-compiled check-gcc and for
arm-none-linux-gnueabihf with native bootstrap and make check.
Ok for trunk?
Matthew
gcc/
2015-08-10 Matthew Wahab <matthew.wa...@arm.com>
PR target/67143
* config/aarch64/atomic.md (atomic_<optab><mode>): Replace
'lconst_atomic' with 'const_atomic'.
(atomic_fetch_<optab><mode>): Likewise.
(atomic_<optab>_fetch<mode>): Likewise.
* config/aarch64/iterators.md (lconst-atomic): Move below
'const_atomic'.
(const_atomic): New.
gcc/testsuite/
2015-08-10 Matthew Wahab <matthew.wa...@arm.com>
Matthias Klose <d...@debian.org>
PR target/67143
* gcc.target/aarch64/pr67143.c: New
diff --git a/gcc/config/aarch64/atomics.md b/gcc/config/aarch64/atomics.md
index 1a38ac0..6e6be99 100644
--- a/gcc/config/aarch64/atomics.md
+++ b/gcc/config/aarch64/atomics.md
@@ -119,7 +119,7 @@
[(set (match_operand:ALLI 0 "aarch64_sync_memory_operand" "+Q")
(unspec_volatile:ALLI
[(atomic_op:ALLI (match_dup 0)
- (match_operand:ALLI 1 "<atomic_op_operand>" "r<lconst_atomic>"))
+ (match_operand:ALLI 1 "<atomic_op_operand>" "r<const_atomic>"))
(match_operand:SI 2 "const_int_operand")] ;; model
UNSPECV_ATOMIC_OP))
(clobber (reg:CC CC_REGNUM))
@@ -164,7 +164,7 @@
(set (match_dup 1)
(unspec_volatile:ALLI
[(atomic_op:ALLI (match_dup 1)
- (match_operand:ALLI 2 "<atomic_op_operand>" "r<lconst_atomic>"))
+ (match_operand:ALLI 2 "<atomic_op_operand>" "r<const_atomic>"))
(match_operand:SI 3 "const_int_operand")] ;; model
UNSPECV_ATOMIC_OP))
(clobber (reg:CC CC_REGNUM))
@@ -209,7 +209,7 @@
[(set (match_operand:ALLI 0 "register_operand" "=&r")
(atomic_op:ALLI
(match_operand:ALLI 1 "aarch64_sync_memory_operand" "+Q")
- (match_operand:ALLI 2 "<atomic_op_operand>" "r<lconst_atomic>")))
+ (match_operand:ALLI 2 "<atomic_op_operand>" "r<const_atomic>")))
(set (match_dup 1)
(unspec_volatile:ALLI
[(match_dup 1) (match_dup 2)
diff --git a/gcc/config/aarch64/iterators.md b/gcc/config/aarch64/iterators.md
index 5d7966d..d3d6af7 100644
--- a/gcc/config/aarch64/iterators.md
+++ b/gcc/config/aarch64/iterators.md
@@ -345,9 +345,6 @@
;; Attribute to describe constants acceptable in logical operations
(define_mode_attr lconst [(SI "K") (DI "L")])
-;; Attribute to describe constants acceptable in atomic logical operations
-(define_mode_attr lconst_atomic [(QI "K") (HI "K") (SI "K") (DI "L")])
-
;; Map a mode to a specific constraint character.
(define_mode_attr cmode [(QI "q") (HI "h") (SI "s") (DI "d")])
@@ -843,6 +840,16 @@
(plus "aarch64_plus_operand")
(minus "aarch64_plus_operand")])
+;; Constants acceptable for atomic operations.
+;; This definition must appear in this file before the iterators it refers to.
+(define_code_attr const_atomic
+ [(plus "I") (minus "I")
+ (xor "<lconst_atomic>") (ior "<lconst_atomic>")
+ (and "<lconst_atomic>")])
+
+;; Attribute to describe constants acceptable in atomic logical operations
+(define_mode_attr lconst_atomic [(QI "K") (HI "K") (SI "K") (DI "L")])
+
;; -------------------------------------------------------------------
;; Int Iterators.
;; -------------------------------------------------------------------
diff --git a/gcc/testsuite/gcc.target/aarch64/pr67143.c b/gcc/testsuite/gcc.target/aarch64/pr67143.c
new file mode 100644
index 0000000..9335b33
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/pr67143.c
@@ -0,0 +1,24 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+
+long a, c;
+int b;
+int d;
+void ut_dbg_assertion_failed() __attribute__((noreturn));
+long dict_index_is_spatial(int *);
+void btr_block_get_func(char *);
+long btr_page_get_level_low(unsigned char *);
+void btr_validate_level(long p1) {
+ unsigned char *e;
+ while (p1 != btr_page_get_level_low(e)) {
+ if (__builtin_expect(b, 0))
+ ut_dbg_assertion_failed();
+ if (dict_index_is_spatial(&d))
+ while (c != 5535) {
+ __sync_add_and_fetch(&a, 536870912);
+ btr_block_get_func("");
+ }
+ }
+ for (long i; i; ++i)
+ btr_validate_level(-i);
+}
