Implement support for 18 of the GNU-compatible __atomic builtins.

This is not quite sufficient for libstdc++'s <atomic>: we still need
__atomic_test_and_set and __atomic_clear, and may need a more complete
__atomic_is_lock_free implementation.

We are also missing an implementation of __atomic_always_lock_free,
__atomic_nand_fetch, and __atomic_fetch_nand, but those aren't needed
for libstdc++.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154579 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 134 insertions, 23 deletions

diff --git a/test/CodeGen/atomic-ops.c b/test/CodeGen/atomic-ops.c
index c94f14023e..24692c7585 100644
--- a/test/CodeGen/atomic-ops.c
+++ b/test/CodeGen/atomic-ops.c
@@ -22,23 +22,80 @@ int fi1(_Atomic(int) *i) {
   return __c11_atomic_load(i, memory_order_seq_cst);
 }
 
+int fi1a(int *i) {
+  // CHECK: @fi1a
+  // CHECK: load atomic i32* {{.*}} seq_cst
+  int v;
+  __atomic_load(i, &v, memory_order_seq_cst);
+  return v;
+}
+
+int fi1b(int *i) {
+  // CHECK: @fi1b
+  // CHECK: load atomic i32* {{.*}} seq_cst
+  return __atomic_load_n(i, memory_order_seq_cst);
+}
+
 void fi2(_Atomic(int) *i) {
   // CHECK: @fi2
   // CHECK: store atomic i32 {{.*}} seq_cst
   __c11_atomic_store(i, 1, memory_order_seq_cst);
 }
 
-void fi3(_Atomic(int) *i) {
+void fi2a(int *i) {
+  // CHECK: @fi2a
+  // CHECK: store atomic i32 {{.*}} seq_cst
+  int v = 1;
+  __atomic_store(i, &v, memory_order_seq_cst);
+}
+
+void fi2b(int *i) {
+  // CHECK: @fi2b
+  // CHECK: store atomic i32 {{.*}} seq_cst
+  __atomic_store_n(i, 1, memory_order_seq_cst);
+}
+
+int fi3(_Atomic(int) *i) {
   // CHECK: @fi3
   // CHECK: atomicrmw and
-  __c11_atomic_fetch_and(i, 1, memory_order_seq_cst);
+  // CHECK-NOT: and
+  return __c11_atomic_fetch_and(i, 1, memory_order_seq_cst);
+}
+
+int fi3a(int *i) {
+  // CHECK: @fi3a
+  // CHECK: atomicrmw xor
+  // CHECK-NOT: xor
+  return __atomic_fetch_xor(i, 1, memory_order_seq_cst);
+}
+
+int fi3b(int *i) {
+  // CHECK: @fi3b
+  // CHECK: atomicrmw add
+  // CHECK: add
+  return __atomic_add_fetch(i, 1, memory_order_seq_cst);
+}
+
+_Bool fi4(_Atomic(int) *i) {
+  // CHECK: @fi4
+  // CHECK: cmpxchg i32*
+  int cmp = 0;
+  return __c11_atomic_compare_exchange_strong(i, &cmp, 1, memory_order_acquire, memory_order_acquire);
+}
+
+_Bool fi4a(int *i) {
+  // CHECK: @fi4
+  // CHECK: cmpxchg i32*
+  int cmp = 0;
+  int desired = 1;
+  return __atomic_compare_exchange(i, &cmp, &desired, 0, memory_order_acquire, memory_order_acquire);
 }
 
-void fi4(_Atomic(int) *i) {
+_Bool fi4b(int *i) {
   // CHECK: @fi4
   // CHECK: cmpxchg i32*
   int cmp = 0;
-  __c11_atomic_compare_exchange_strong(i, &cmp, 1, memory_order_acquire, memory_order_acquire);
+  return __atomic_compare_exchange_n(i, &cmp, 1, 1, memory_order_acquire, memory_order_acquire);
 }
 
 float ff1(_Atomic(float) *d) {
@@ -70,6 +127,13 @@ int* fp2(_Atomic(int*) *p) {
   return __c11_atomic_fetch_add(p, 1, memory_order_relaxed);
 }
 
+int *fp2a(int **p) {
+  // CHECK: @fp2a
+  // CHECK: store i32 4
+  // CHECK: atomicrmw sub {{.*}} monotonic
+  return __atomic_fetch_sub(p, 1, memory_order_relaxed);
+}
+
 _Complex float fc(_Atomic(_Complex float) *c) {
   // CHECK: @fc
   // CHECK: atomicrmw xchg i64*
@@ -83,6 +147,20 @@ X fs(_Atomic(X) *c) {
   return __c11_atomic_exchange(c, (X){2}, memory_order_seq_cst);
 }
 
+X fsa(X *c, X *d) {
+  // CHECK: @fsa
+  // CHECK: atomicrmw xchg i32*
+  X ret;
+  __atomic_exchange(c, d, &ret, memory_order_seq_cst);
+  return ret;
+}
+
+_Bool fsb(_Bool *c) {
+  // CHECK: @fsb
+  // CHECK: atomicrmw xchg i8*
+  return __atomic_exchange_n(c, 1, memory_order_seq_cst);
+}
+
 int lock_free() {
   // CHECK: @lock_free
   // CHECK: ret i32 1
@@ -96,33 +174,80 @@ int lock_free() {
 struct foo {
   int big[128];
 };
+struct bar {
+  char c[3];
+};
 
+struct bar smallThing, thing1, thing2;
+struct foo bigThing;
 _Atomic(struct foo) bigAtomic;
 
 void structAtomicStore() {
   // CHECK: @structAtomicStore
   struct foo f = {0};
   __c11_atomic_store(&bigAtomic, f, 5);
-  // CHECK: call void @__atomic_store(i32 512, i8* bitcast (%struct.foo* @bigAtomic to i8*), 
+  // CHECK: call void @__atomic_store(i32 512, i8* bitcast ({{.*}} @bigAtomic to i8*),
+
+  struct bar b = {0};
+  __atomic_store(&smallThing, &b, 5);
+  // CHECK: call void @__atomic_store(i32 3, i8* {{.*}} @smallThing
+
+  __atomic_store(&bigThing, &f, 5);
+  // CHECK: call void @__atomic_store(i32 512, i8* {{.*}} @bigThing
 }
 void structAtomicLoad() {
   // CHECK: @structAtomicLoad
   struct foo f = __c11_atomic_load(&bigAtomic, 5);
-  // CHECK: call void @__atomic_load(i32 512, i8* bitcast (%struct.foo* @bigAtomic to i8*), 
+  // CHECK: call void @__atomic_load(i32 512, i8* bitcast ({{.*}} @bigAtomic to i8*),
+
+  struct bar b;
+  __atomic_load(&smallThing, &b, 5);
+  // CHECK: call void @__atomic_load(i32 3, i8* {{.*}} @smallThing
+
+  __atomic_load(&bigThing, &f, 5);
+  // CHECK: call void @__atomic_load(i32 512, i8* {{.*}} @bigThing
 }
 struct foo structAtomicExchange() {
   // CHECK: @structAtomicExchange
   struct foo f = {0};
+  struct foo old;
+  __atomic_exchange(&f, &bigThing, &old, 5);
+  // CHECK: call void @__atomic_exchange(i32 512, {{.*}}, i8* bitcast ({{.*}} @bigThing to i8*),
+
   return __c11_atomic_exchange(&bigAtomic, f, 5);
-  // CHECK: call void @__atomic_exchange(i32 512, i8* bitcast (%struct.foo* @bigAtomic to i8*), 
+  // CHECK: call void @__atomic_exchange(i32 512, i8* bitcast ({{.*}} @bigAtomic to i8*),
 }
 int structAtomicCmpExchange() {
   // CHECK: @structAtomicCmpExchange
+  _Bool x = __atomic_compare_exchange(&smallThing, &thing1, &thing2, 1, 5, 5);
+  // CHECK: call zeroext i1 @__atomic_compare_exchange(i32 3, {{.*}} @smallThing{{.*}} @thing1{{.*}} @thing2
+
   struct foo f = {0};
   struct foo g = {0};
   g.big[12] = 12;
-  return __c11_atomic_compare_exchange_strong(&bigAtomic, &f, g, 5, 5);
-  // CHECK: call zeroext i1 @__atomic_compare_exchange(i32 512, i8* bitcast (%struct.foo* @bigAtomic to i8*), 
+  return x & __c11_atomic_compare_exchange_strong(&bigAtomic, &f, g, 5, 5);
+  // CHECK: call zeroext i1 @__atomic_compare_exchange(i32 512, i8* bitcast ({{.*}} @bigAtomic to i8*),
+}
+
+// Check that no atomic operations are used in any initialisation of _Atomic
+// types.
+_Atomic(int) atomic_init_i = 42;
+
+// CHECK: @atomic_init_foo
+void atomic_init_foo()
+{
+  // CHECK-NOT: }
+  // CHECK-NOT: atomic
+  // CHECK: store
+  _Atomic(int) j = 12;
+
+  // CHECK-NOT: }
+  // CHECK-NOT: atomic
+  // CHECK: store
+  __c11_atomic_init(&j, 42);
+
+  // CHECK-NOT: atomic
+  // CHECK: }
 }
 
 #endif
diff --git a/test/CodeGen/atomic_init.c b/test/CodeGen/atomic_init.c
deleted file mode 100644
index 6f773bef48..0000000000
--- a/test/CodeGen/atomic_init.c
+++ /dev/null
@@ -1,14 +0,0 @@
-// RUN: %clang_cc1 -emit-llvm %s -o - | FileCheck %s
-
-// Check that no atomic operations are used in any initialisation of _Atomic
-// types.  
-
-_Atomic(int) i = 42;
-
-void foo()
-{
-  _Atomic(int) j = 12; // CHECK: store 
-                       // CHECK-NOT: atomic
-  __c11_atomic_init(&j, 42); // CHECK: store 
-                             // CHECK-NOT: atomic
-}