adds initial version of lwc

lwc/src/ascon/arch/rv32/ise.h

@@ -0,0 +1,18 @@
+// Copyright (C) 2021 SCARV project <info@scarv.org>
+//
+// Use of this source code is restricted per the MIT license, a copy of which 
+// can be found at https://opensource.org/licenses/MIT (or should be included 
+// as LICENSE.txt within the associated archive or repository).
+
+// ============================================================================
+
+#if ( ASCON_RV32_TYPE2 )
+.macro ascon.sigma.lo       rd, rs1, rs2, imm
+.insn r CUSTOM_1, 7, \imm+( 0*32), \rd, \rs1, \rs2
+.endm
+.macro ascon.sigma.hi       rd, rs1, rs2, imm
+.insn r CUSTOM_1, 7, \imm+( 1*32), \rd, \rs1, \rs2
+.endm
+#endif
+
+// ============================================================================