/* $NetBSD: frame_regs.h,v 1.8 2021/04/17 20:12:55 rillig Exp $ */ #ifndef _AMD64_FRAME_REGS_H_ #define _AMD64_FRAME_REGS_H_ /* * amd64 registers (and friends) ordered as in a trap/interrupt/syscall frame. * Also the indexes into the 'general register state' (__greg_t) passed to * userland. * Historically they were in the same order, but the order in the frames * has been changed to improve syscall efficiency. * * Notes: * 1) gdb (amd64nbsd-tdep.c) has a lookup table that assumes the __greg_t * ordering. * 2) src/lib/libc/arch/x86_64/gen/makecontext.c assumes that the first * 6 entries in the __greg_t array match the registers used to pass * function arguments. * 3) The 'struct reg' from machine/reg.h has to match __greg_t. * Since they are both arrays and indexed with the same tokens this * shouldn't be a problem, but is rather confusing. * This assumption is made in a lot of places! * 4) There might be other code out there that relies on the ordering. * * The first entries below match the registers used for syscall arguments * (%rcx is destroyed by the syscall instruction, the libc system call * stubs copy %rcx to %r10). * arg6-arg9 are copied from the user stack for system calls with more * than 6 args (SYS_MAXSYSARGS is 8, + 2 entries for SYS___SYSCALL). */ #define _FRAME_REG(greg, freg) \ greg(rdi, RDI, 0) /* tf_rdi */ \ greg(rsi, RSI, 1) /* tf_rsi */ \ greg(rdx, RDX, 2) /* tf_rdx */ \ greg(r10, R10, 6) /* tf_r10 */ \ greg(r8, R8, 4) /* tf_r8 */ \ greg(r9, R9, 5) /* tf_r9 */ \ freg(arg6, @, @) /* tf_arg6: syscall arg from stack */ \ freg(arg7, @, @) /* tf_arg7: syscall arg from stack */ \ freg(arg8, @, @) /* tf_arg8: syscall arg from stack */ \ freg(arg9, @, @) /* tf_arg9: syscall arg from stack */ \ greg(rcx, RCX, 3) /* tf_rcx */ \ greg(r11, R11, 7) /* tf_r11 */ \ greg(r12, R12, 8) /* tf_r12 */ \ greg(r13, R13, 9) /* tf_r13 */ \ greg(r14, R14, 10) /* tf_r14 */ \ greg(r15, R15, 11) /* tf_r15 */ \ greg(rbp, RBP, 12) /* tf_rbp */ \ greg(rbx, RBX, 13) /* tf_rbx */ \ greg(rax, RAX, 14) /* tf_rax */ \ greg(gs, GS, 15) /* tf_gs */ \ greg(fs, FS, 16) /* tf_fs */ \ greg(es, ES, 17) /* tf_es */ \ greg(ds, DS, 18) /* tf_ds */ \ greg(trapno, TRAPNO, /* tf_trapno */ \ 19) \ /* Below portion defined in hardware */ \ greg(err, ERR, 20) /* tf_err: Dummy inserted if not defined */ \ greg(rip, RIP, 21) /* tf_rip */ \ greg(cs, CS, 22) /* tf_cs */ \ greg(rflags, RFLAGS, /* tf_rflags */ \ 23) \ /* These are pushed unconditionally on the x86-64 */ \ greg(rsp, RSP, 24) /* tf_rsp */ \ greg(ss, SS, 25) /* tf_ss */ #define _FRAME_NOREG(reg, REG, idx) #define _FRAME_GREG(greg) _FRAME_REG(greg, _FRAME_NOREG) #endif
