Old recompiler improvements: limited in-block IRQ checking to floppy IRQ's only, rewrote the GPF handlers in ASM, and changed the recompiled INC and DEC instructions to actually use INC and DEC on host. Also removed the keyboard_at.c timer hack.

src/codegen/codegen_x86.c

@@ -1440,6 +1440,7 @@ void codegen_block_start_recompile(codeblock_t *block)
         block->status = cpu_cur_status;
 
         block_pos = BLOCK_GPF_OFFSET;
+#ifdef OLD_GPF
         addbyte(0xc7); /*MOV [ESP],0*/
         addbyte(0x04);
         addbyte(0x24);
@@ -1451,6 +1452,16 @@ void codegen_block_start_recompile(codeblock_t *block)
         addlong(0);
         addbyte(0xe8); /*CALL x86gpf*/
         addlong((uint32_t)x86gpf - (uint32_t)(&codeblock[block_current].data[block_pos + 4]));
+#else
+	addbyte(0xc6);	/* mov byte ptr[&(cpu_state.abrt)],ABRT_GPF */
+	addbyte(0x05);
+	addlong((uint32_t) (uintptr_t) &(cpu_state.abrt));
+	addbyte(ABRT_GPF);
+	addbyte(0x31);	/* xor eax,eax */
+	addbyte(0xc0);
+	addbyte(0xa3);	/* mov [&(abrt_error)],eax */
+	addlong((uint32_t) (uintptr_t) &(abrt_error));
+#endif
         block_pos = BLOCK_EXIT_OFFSET; /*Exit code*/
         addbyte(0x83); /*ADDL $16,%esp*/
         addbyte(0xC4);