3 files changed, 42 insertions, 0 deletions

diff --git a/tests/ref29.txt b/tests/ref29.txt
new file mode 100644
index 00000000..6b25f7de
--- /dev/null
+++ b/tests/ref29.txt
@@ -0,0 +1,2 @@
+Lock XADD: Res = 0x456, Ed = 0x579
+Lock XCHG: Res = 0x579, Ed = 0x123
diff --git a/tests/test29 b/tests/test29
new file mode 100755
index 00000000..0c4a63da
--- /dev/null
+++ b/tests/test29
Binary files differdiff --git a/tests/test29.c b/tests/test29.c
new file mode 100644
index 00000000..96384251
--- /dev/null
+++ b/tests/test29.c
@@ -0,0 +1,40 @@
+#include <stdio.h>
+#include <string.h>
+#include <stddef.h>
+#include <stdint.h>
+// Build with `gcc -march=core2 -O0 test29.c -o test29`
+
+uint64_t lock_xadd(uint64_t Gd, uint64_t volatile* Ed) {
+uint64_t Res;
+asm(
+"lock xadd %[_Gd], (%[_Ed])\n"
+"movq %[_Gd], %[_Res]\n"
+: [_Res] "+r"(Res)
+: [_Gd] "r"(Gd)
+, [_Ed] "r"(Ed)
+);
+return Res;
+}
+
+uint64_t lock_xchg(uint64_t Gd, uint64_t volatile* Ed) {
+uint64_t Res;
+asm(
+"lock xchg %[_Gd], (%[_Ed])\n"
+"movq %[_Gd], %[_Res]\n"
+: [_Res] "+r"(Res)
+: [_Gd] "r"(Gd)
+, [_Ed] "r"(Ed)
+);
+return Res;
+}
+
+int main() {
+uint64_t Gd = 0x123;
+uint64_t volatile Ed = 0x456;
+uint64_t Res = lock_xadd(Gd, &Ed);
+printf("Lock XADD: Res = 0x%lx, Ed = 0x%lx\n", Res, Ed);
+Gd = 0x123;
+Res = lock_xchg(Gd, &Ed);
+printf("Lock XCHG: Res = 0x%lx, Ed = 0x%lx\n", Res, Ed);
+return 0;
+}