Zicfilp: Implement lpad insn behavior

riscv/insns/lpad.h

@@ -0,0 +1,6 @@
+if (ZICFILP_xLPE(STATE.v, STATE.prv) && STATE.elp == elp_t::LP_EXPECTED) {
+  software_check(pc % 4 == 0 &&
+                 ((READ_REG(7) & 0xFFFFF000ULL) == (static_cast<uint64_t>(insn.u_imm()) & 0xFFFFF000ULL) || insn.u_imm() == 0LL),
+                 LANDING_PAD_FAULT);
+  STATE.elp = elp_t::NO_LP_EXPECTED;
+}

riscv/riscv.mk.in

@@ -1392,6 +1392,9 @@ riscv_insn_ext_zimop = \
 	mop_r_N \
 	mop_rr_N \
 
+riscv_insn_ext_zicfilp = \
+	lpad
+
 riscv_insn_ext_zvk = \
 	$(riscv_insn_ext_zvbb) \
 	$(riscv_insn_ext_zvbc) \
@@ -1431,6 +1434,7 @@ riscv_insn_list = \
 	$(riscv_insn_smrnmi) \
 	$(riscv_insn_svinval) \
 	$(riscv_insn_ext_zimop) \
+	$(riscv_insn_ext_zicfilp) \
 
 riscv_gen_srcs = $(addsuffix .cc,$(riscv_insn_list))