1 files changed, 10 insertions, 0 deletions
diff --git a/riscv/insns/fsrw.h b/riscv/insns/fsrw.h
new file mode 100644
index 0000000..1511fbe
--- /dev/null
+++ b/riscv/insns/fsrw.h
@@ -0,0 +1,10 @@
+require_rv64;
+require_extension('B');
+int shamt = RS2 & 63;
+reg_t a = RS1, b = RS3;
+if (shamt >= 32) {
+	a = RS3, b = RS1;
+	shamt -= 32;
+}
+int rshamt = -shamt & 31;
+WRITE_RD(sext32(shamt ? (b << rshamt) | (zext32(a) >> shamt) : a));