ref: a2be120ea93ae67447315da268fa336650cd5149
dir: /sys/src/9/xen/plan9l.s/
#include "xendefs.h" #include "mem.h" /* * This must match io.h. */ #define VectorSYSCALL 0x40 /* * Used to get to the first process: * set up an interrupt return frame and IRET to user level. */ TEXT touser(SB), $0 PUSHL $(UDSEL) /* old ss */ MOVL sp+0(FP), AX /* old sp */ PUSHL AX MOVL $0x200, AX /* interrupt enable flag */ PUSHL AX /* old flags */ PUSHL $(UESEL) /* old cs */ PUSHL $(UTZERO+32) /* old pc */ MOVL $(UDSEL), AX MOVW AX, DS MOVW AX, ES MOVW AX, GS MOVW AX, FS IRETL /* * This is merely _strayintr from l.s optimised to vector * to syscall() without going through trap(). */ TEXT _syscallintr(SB), $0 PUSHL $VectorSYSCALL /* trap type */ PUSHL DS PUSHL ES PUSHL FS PUSHL GS PUSHAL MOVL $(KDSEL), AX MOVW AX, DS MOVW AX, ES PUSHL SP CALL syscall(SB) POPL AX POPAL POPL GS POPL FS POPL ES POPL DS ADDL $8, SP /* pop error code and trap type */ IRETL