feat: add support for the __sync_swap builtin

Adds support for the __sync_swap builtin

Signed-off-by: vishruth-thimmaiah <[email protected]>

Author: vishruth-thimmaiah

clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp

@@ -2119,7 +2119,7 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
   case Builtin::BI__sync_swap_4:
   case Builtin::BI__sync_swap_8:
   case Builtin::BI__sync_swap_16:
-    llvm_unreachable("BI__sync_swap1 like NYI");
+    return emitBinaryAtomic(*this, cir::AtomicFetchKind::Xchg, E);
 
   case Builtin::BI__sync_lock_test_and_set_1:
   case Builtin::BI__sync_lock_test_and_set_2:

clang/test/CIR/CodeGen/atomic.cpp

@@ -1271,3 +1271,75 @@ void lock_test_and_set(unsigned short* a, short b) {
 void lock_test_and_set(unsigned char* a, char b) {
   unsigned char c = __sync_lock_test_and_set(a, b);
 }
+
+// CHECK-LABEL: @_Z4swapPii
+// CHECK: cir.atomic.fetch(xchg, {{.*}} : !cir.ptr<!s32i>, {{.*}} : !s32i, seq_cst) fetch_first : !s32i
+
+// LLVM-LABEL: @_Z4swapPii
+// LLVM: atomicrmw xchg ptr {{.*}}, i32 {{.*}} seq_cst, align 4
+void swap(int* a, int b) {
+  int c = __sync_swap(a, b);
+}
+
+// CHECK-LABEL: @_Z4swapPll
+// CHECK: cir.atomic.fetch(xchg, {{.*}} : !cir.ptr<!s64i>, {{.*}} : !s64i, seq_cst) fetch_first : !s64i
+
+// LLVM-LABEL: @_Z4swapPll
+// LLVM: atomicrmw xchg ptr {{.*}}, i64 {{.*}} seq_cst, align 8
+void swap(long* a, long b) {
+  long c = __sync_swap(a, b);
+}
+
+// CHECK-LABEL: @_Z4swapPss
+// CHECK: cir.atomic.fetch(xchg, {{.*}} : !cir.ptr<!s16i>, {{.*}} : !s16i, seq_cst) fetch_first : !s16i
+
+// LLVM-LABEL: @_Z4swapPss
+// LLVM: atomicrmw xchg ptr {{.*}}, i16 {{.*}} seq_cst, align 2
+void swap(short* a, short b) {
+  short c = __sync_swap(a, 2);
+}
+
+// CHECK-LABEL: @_Z4swapPcc
+// CHECK: cir.atomic.fetch(xchg, {{.*}} : !cir.ptr<!s8i>, {{.*}} : !s8i, seq_cst) fetch_first : !s8i
+
+// LLVM-LABEL: @_Z4swapPcc
+// LLVM: atomicrmw xchg ptr {{.*}}, i8 {{.*}} seq_cst, align 1
+void swap(char* a, char b) {
+  char c = __sync_swap(a, b);
+}
+
+// CHECK-LABEL: @_Z4swapPji
+// CHECK: cir.atomic.fetch(xchg, {{.*}} : !cir.ptr<!u32i>, {{.*}} : !u32i, seq_cst) fetch_first : !u32i
+
+// LLVM-LABEL: @_Z4swapPji
+// LLVM: atomicrmw xchg ptr {{.*}}, i32 {{.*}} seq_cst, align 4
+void swap(unsigned int* a, int b) {
+  unsigned int c = __sync_swap(a, b);
+}
+
+// CHECK-LABEL: @_Z4swapPml
+// CHECK: cir.atomic.fetch(xchg, {{.*}} : !cir.ptr<!u64i>, {{.*}} : !u64i, seq_cst) fetch_first : !u64i
+
+// LLVM-LABEL: @_Z4swapPml
+// LLVM: atomicrmw xchg ptr {{.*}}, i64 {{.*}} seq_cst, align 8
+void swap(unsigned long* a, long b) {
+  unsigned long c = __sync_swap(a, b);
+}
+
+// CHECK-LABEL: @_Z4swapPts
+// CHECK: cir.atomic.fetch(xchg, {{.*}} : !cir.ptr<!u16i>, {{.*}} : !u16i, seq_cst) fetch_first : !u16i
+//
+// LLVM-LABEL: @_Z4swapPts
+// LLVM: atomicrmw xchg ptr {{.*}}, i16 {{.*}} seq_cst, align 2
+void swap(unsigned short* a, short b) {
+  unsigned long long c = __sync_swap(a, b);
+}
+
+// CHECK-LABEL: @_Z4swapPhc
+// CHECK: cir.atomic.fetch(xchg, {{.*}} : !cir.ptr<!u8i>, {{.*}} : !u8i, seq_cst) fetch_first : !u8i
+
+// LLVM-LABEL: @_Z4swapPhc
+// LLVM: atomicrmw xchg ptr {{.*}}, i8 {{.*}} seq_cst, align 1
+void swap(unsigned char* a, char b) {
+  unsigned char c = __sync_swap(a, b);
+}