# HG changeset patch
# User Michael Pavone <pavone@retrodev.com>
# Date 1431918207 25200
# Node ID b707a8ddc202853708dcce9ed6f9a1b351419eb6
# Parent  1c2020d3e2758e2ecbef0967009b0a3df127d056
Make sure z80_save_reg does nothing when there is no register in the reg field of the instruction. This fixes a bug that corrupted SP in the MDEM 2011 demo

diff -r 1c2020d3e275 -r b707a8ddc202 z80_to_x86.c
--- a/z80_to_x86.c	Sun May 17 19:14:41 2015 -0700
+++ b/z80_to_x86.c	Sun May 17 20:03:27 2015 -0700
@@ -81,6 +81,9 @@
 void z80_save_reg(z80inst * inst, z80_options * opts)
 {
 	code_info *code = &opts->gen.code;
+	if (inst->reg == Z80_USE_IMMED || inst->reg == Z80_UNUSED) {
+		return;
+	}
 	if (inst->reg == Z80_IYH) {
 		if ((inst->addr_mode & 0x1F) == Z80_REG && inst->ea_reg == Z80_IYL) {
 			ror_ir(code, 8, opts->regs[Z80_IY], SZ_W);