1 files changed, 42 insertions, 0 deletions
diff --git a/isa/rv64mi/instret_overflow.S b/isa/rv64mi/instret_overflow.S
new file mode 100644
index 0000000..f026ac0
--- /dev/null
+++ b/isa/rv64mi/instret_overflow.S
@@ -0,0 +1,42 @@
+# See LICENSE for license details.
+
+#*****************************************************************************
+# minstret_overflow.S
+#-----------------------------------------------------------------------------
+#
+# Test if overflow of instret is handled correctly
+#
+
+#include "riscv_test.h"
+#include "test_macros.h"
+
+RVTEST_RV64M
+RVTEST_CODE_BEGIN
+
+  # The value written to instret will be the value read by the following
+  # instruction (i.e. the increment is suppressed)
+  TEST_CASE(2, a0, 0, csrwi minstret, 0; csrr a0, minstret);
+
+#if __riscv_xlen == 32
+  # Writes to instreth are considered writes to instret and so also
+  # suppress the increment
+  TEST_CASE(3, a0, 0, li t0, 0xffffffff; csrw minstret, t0; csrw minstreth, t0; nop; csrr a0, minstret);
+  TEST_CASE(4, a0, 0, csrr a0, minstreth);
+#endif
+
+2:
+  TEST_PASSFAIL
+
+  .align 2
+  .global mtvec_handler
+mtvec_handler:
+  j fail
+
+RVTEST_CODE_END
+
+  .data
+RVTEST_DATA_BEGIN
+
+  TEST_DATA
+
+RVTEST_DATA_END