freebsd-dev/sys/alpha/include/asm.h
Andrew Gallatin 8c8fdd1fa2 Sync up to v 1.9 of NetBSD's db_trace.c to get access to the
greatly improved traceback code from Ross Harvey.  This code
requires the use of more traceback friendly temporary labels
at kernel entry points, hence the changes to exception.s and
asm.h

Reviewed by: jhb, dfr
Obtained from: NetBSD
MFC after: 1 week
2001-06-08 13:38:02 +00:00

651 lines
15 KiB
C

/*
* Copyright (c) 1991,1990,1989,1994,1995,1996 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
* From: NetBSD: asm.h,v 1.18 1997/11/03 04:22:06 ross Exp
* $FreeBSD$
*/
/*
* Assembly coding style
*
* This file contains macros and register defines to
* aid in writing more readable assembly code.
* Some rules to make assembly code understandable by
* a debugger are also noted.
*
* The document
*
* "ALPHA Calling Standard", DEC 27-Apr-90
*
* defines (a superset of) the rules and conventions
* we use. While we make no promise of adhering to
* such standard and its evolution (esp where we
* can get faster code paths) it is certainly intended
* that we be interoperable with such standard.
*
* In this sense, this file is a proper part of the
* definition of the (software) Alpha architecture.
*/
/*
* Symbolic register names and register saving rules
*
* Legend:
* T Saved by caller (Temporaries)
* S Saved by callee (call-Safe registers)
*/
#define v0 $0 /* (T) return value */
#define t0 $1 /* (T) temporary registers */
#define t1 $2
#define t2 $3
#define t3 $4
#define t4 $5
#define t5 $6
#define t6 $7
#define t7 $8
#define s0 $9 /* (S) call-safe registers */
#define s1 $10
#define s2 $11
#define s3 $12
#define s4 $13
#define s5 $14
#define s6 $15
#define a0 $16 /* (T) argument registers */
#define a1 $17
#define a2 $18
#define a3 $19
#define a4 $20
#define a5 $21
#define t8 $22 /* (T) temporary registers */
#define t9 $23
#define t10 $24
#define t11 $25
#define ra $26 /* (T) return address */
#define t12 $27 /* (T) another temporary */
#define at_reg $28 /* (T) assembler scratch */
#define gp $29 /* (T) (local) data pointer */
#define sp $30 /* (S) stack pointer */
#define zero $31 /* wired zero */
/* In the kernel, we use t7 to point at the per-cpu globals. */
#ifdef _KERNEL
#define globalp $8
#endif
/* Floating point registers (XXXX VERIFY THIS) */
#define fv0 $f0 /* (T) return value (real) */
#define fv1 $f1 /* (T) return value (imaginary)*/
#define ft0 fv1
#define fs0 $f2 /* (S) call-safe registers */
#define fs1 $f3
#define fs2 $f4
#define fs3 $f5
#define fs4 $f6
#define fs5 $f7
#define fs6 $f8
#define fs7 $f9
#define ft1 $f10 /* (T) temporary registers */
#define ft2 $f11
#define ft3 $f12
#define ft4 $f13
#define ft5 $f14
#define ft6 $f15
#define fa0 $f16 /* (T) argument registers */
#define fa1 $f17
#define fa2 $f18
#define fa3 $f19
#define fa4 $f20
#define fa5 $f21
#define ft7 $f22 /* (T) more temporaries */
#define ft8 $f23
#define ft9 $f24
#define ft10 $f25
#define ft11 $f26
#define ft12 $f27
#define ft13 $f28
#define ft14 $f29
#define ft15 $f30
#define fzero $f31 /* wired zero */
/* Other DEC standard names */
#define ai $25 /* (T) argument information */
#define pv $27 /* (T) procedure value */
/*
* Useful stuff.
*/
#ifdef __STDC__
#define __CONCAT(a,b) a ## b
#else
#define __CONCAT(a,b) a/**/b
#endif
#define ___CONCAT(a,b) __CONCAT(a,b)
/*
* Macro to make a local label name.
*/
#define LLABEL(name,num) ___CONCAT(___CONCAT(L,name),num)
/*
*
* Debuggers need symbol table information to be able to properly
* decode a stack trace. The minimum that should be provided is:
*
* name:
* .proc name,numargs
*
* where "name" is the function's name;
* "numargs" how many arguments it expects. For varargs
* procedures this should be a negative number,
* indicating the minimum required number of
* arguments (which is at least 1);
*
* NESTED functions (functions that call other functions) should define
* how they handle their stack frame in a .frame directive:
*
* .frame framesize, pc_reg, i_mask, f_mask
*
* where "framesize" is the size of the frame for this function, in bytes.
* That is:
* new_sp + framesize == old_sp
* Framesizes should be rounded to a cacheline size.
* Note that old_sp plays the role of a conventional
* "frame pointer";
* "pc_reg" is either a register which preserves the caller's PC
* or 'std', if std the saved PC should be stored at
* old_sp-8
* "i_mask" is a bitmask that indicates which of the integer
* registers are saved. See the M_xx defines at the
* end for the encoding of this 32bit value.
* "f_mask" is the same, for floating point registers.
*
* Note, 10/31/97: This is interesting but it isn't the way gcc outputs
* frame directives and it isn't the way the macros below output them
* either. Frame directives look like this:
*
* .frame $15,framesize,$26,0
*
* If no fp is set up then $30 should be used instead of $15.
* Also, gdb expects to find a <lda sp,-framesize(sp)> at the beginning
* of a procedure. Don't use things like sub sp,framesize,sp for this
* reason. End Note 10/31/97. ross@netbsd.org
*
* Note that registers should be saved starting at "old_sp-8", where the
* return address should be stored. Other registers follow at -16-24-32..
* starting from register 0 (if saved) and up. Then float registers (ifany)
* are saved.
*
* If you need to alias a leaf function, or to provide multiple entry points
* use the LEAF() macro for the main entry point and XLEAF() for the other
* additional/alternate entry points.
* "XLEAF"s must be nested within a "LEAF" and a ".end".
* Similar rules for nested routines, e.g. use NESTED/XNESTED
* Symbols that should not be exported can be declared with the STATIC_xxx
* macros.
*
* All functions must be terminated by the END macro
*
* It is conceivable, although currently at the limits of compiler
* technology, that while performing inter-procedural optimizations
* the compiler/linker be able to avoid unnecessary register spills
* if told about the register usage of LEAF procedures (and by transitive
* closure of NESTED procedures as well). Assembly code can help
* this process using the .reguse directive:
*
* .reguse i_mask, f_mask
*
* where the register masks are built as above or-ing M_xx defines.
*
*
* All symbols are internal unless EXPORTed. Symbols that are IMPORTed
* must be appropriately described to the debugger.
*
*/
/*
* for `.loc' uses
*/
.file 1 __FILE__
/*
* MCOUNT
*/
#if !defined(GPROF) && !defined(PROF)
#define MCOUNT /* nothing */
#else
#define MCOUNT \
.set noat; \
jsr at_reg,_mcount; \
.set at
#endif
/*
* PALVECT, ESETUP, and ERSAVE
* Declare a palcode transfer point, and carefully construct
* gdb symbols with an unusual _negative_ register-save offset
* so that gdb can find the otherwise lost PC and then
* invert the vector for traceback. Also, fix up framesize,
* allowing for the palframe for the same reason.
*/
#define PALVECT(_name_) \
ESETUP(_name_); \
ERSAVE(); \
br pv, 1001f; \
1001:; \
LDGP(pv)
#define ESETUP(_name_) \
.loc 1 __LINE__; \
.globl _name_; \
.ent _name_ 0; \
_name_:; \
.set noat; \
lda sp,-(FRAME_SW_SIZE*8)(sp); \
.frame $30,(FRAME_SW_SIZE+6)*8,$26,0; /* give gdb the real size */\
.mask 0x4000000,-0x28; \
.set at
#define ERSAVE() \
.set noat; \
stq at_reg,(FRAME_AT*8)(sp); \
.set at; \
stq ra,(FRAME_RA*8)(sp); \
.loc 1 __LINE__; \
bsr ra,exception_save_regs /* jmp/CALL trashes pv/t12 */
/*
* LEAF
* Declare a global leaf function.
* A leaf function does not call other functions AND does not
* use any register that is callee-saved AND does not modify
* the stack pointer.
*/
#define LEAF(_name_,_n_args_) \
.globl _name_; \
.ent _name_ 0; \
_name_:; \
.frame sp,0,ra; \
MCOUNT
/* should have been
.proc _name_,_n_args_; \
.frame 0,ra,0,0
*/
#define LEAF_NOPROFILE(_name_,_n_args_) \
.globl _name_; \
.ent _name_ 0; \
_name_:; \
.frame sp,0,ra
/* should have been
.proc _name_,_n_args_; \
.frame 0,ra,0,0
*/
/*
* STATIC_LEAF
* Declare a local leaf function.
*/
#define STATIC_LEAF(_name_,_n_args_) \
.ent _name_ 0; \
_name_:; \
.frame sp,0,ra; \
MCOUNT
/* should have been
.proc _name_,_n_args_; \
.frame 0,ra,0,0
*/
/*
* XLEAF
* Global alias for a leaf function, or alternate entry point
*/
#define XLEAF(_name_,_n_args_) \
.globl _name_; \
.aent _name_ 0; \
_name_:
/* should have been
.aproc _name_,_n_args_;
*/
/*
* STATIC_XLEAF
* Local alias for a leaf function, or alternate entry point
*/
#define STATIC_XLEAF(_name_,_n_args_) \
.aent _name_ 0; \
_name_:
/* should have been
.aproc _name_,_n_args_;
*/
/*
* NESTED
* Declare a (global) nested function
* A nested function calls other functions and needs
* therefore stack space to save/restore registers.
*/
#define NESTED(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \
.globl _name_; \
.ent _name_ 0; \
_name_:; \
.frame sp,_framesize_,_pc_reg_; \
.livereg _i_mask_,_f_mask_; \
MCOUNT
/* should have been
.proc _name_,_n_args_; \
.frame _framesize_, _pc_reg_, _i_mask_, _f_mask_
*/
#define NESTED_NOPROFILE(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \
.globl _name_; \
.ent _name_ 0; \
_name_:; \
.frame sp,_framesize_,_pc_reg_; \
.livereg _i_mask_,_f_mask_
/* should have been
.proc _name_,_n_args_; \
.frame _framesize_, _pc_reg_, _i_mask_, _f_mask_
*/
/*
* STATIC_NESTED
* Declare a local nested function.
*/
#define STATIC_NESTED(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \
.ent _name_ 0; \
_name_:; \
.frame sp,_framesize_,_pc_reg_; \
.livereg _i_mask_,_f_mask_; \
MCOUNT
/* should have been
.proc _name_,_n_args_; \
.frame _framesize_, _pc_reg_, _i_mask_, _f_mask_
*/
/*
* XNESTED
* Same as XLEAF, for a nested function.
*/
#define XNESTED(_name_,_n_args_) \
.globl _name_; \
.aent _name_ 0; \
_name_:
/* should have been
.aproc _name_,_n_args_;
*/
/*
* STATIC_XNESTED
* Same as STATIC_XLEAF, for a nested function.
*/
#define STATIC_XNESTED(_name_,_n_args_) \
.aent _name_ 0; \
_name_:
/* should have been
.aproc _name_,_n_args_;
*/
/*
* END
* Function delimiter
*/
#define END(_name_) \
.end _name_
/*
* CALL
* Function invocation
*/
#define CALL(_name_) \
.loc 1 __LINE__; \
jsr ra,_name_; \
ldgp gp,0(ra)
/* but this would cover longer jumps
br ra,.+4; \
bsr ra,_name_
*/
/*
* RET
* Return from function
*/
#define RET \
ret zero,(ra),1
/*
* EXPORT
* Export a symbol
*/
#define EXPORT(_name_) \
.globl _name_; \
_name_:
/*
* IMPORT
* Make an external name visible, typecheck the size
*/
#define IMPORT(_name_, _size_) \
.extern _name_,_size_
/*
* ABS
* Define an absolute symbol
*/
#define ABS(_name_, _value_) \
.globl _name_; \
_name_ = _value_
/*
* BSS
* Allocate un-initialized space for a global symbol
*/
#define BSS(_name_,_numbytes_) \
.comm _name_,_numbytes_
/*
* VECTOR
* Make an exception entry point look like a called function,
* to make it digestible to the debugger (KERNEL only)
*/
#define VECTOR(_name_, _i_mask_) \
.globl _name_; \
.ent _name_ 0; \
_name_:; \
.mask _i_mask_|IM_EXC,0; \
.frame sp,MSS_SIZE,ra;
/* .livereg _i_mask_|IM_EXC,0 */
/* should have been
.proc _name_,1; \
.frame MSS_SIZE,$31,_i_mask_,0; \
*/
/*
* MSG
* Allocate space for a message (a read-only ascii string)
*/
#define ASCIZ .asciz
#define MSG(msg,reg,label) \
lda reg, label; \
.data; \
label: ASCIZ msg; \
.text;
/*
* PRINTF
* Print a message
*/
#define PRINTF(msg,label) \
MSG(msg,a0,label); \
CALL(printf)
/*
* PANIC
* Fatal error (KERNEL)
*/
#define PANIC(msg,label) \
MSG(msg,a0,label); \
CALL(panic)
/*
* Register mask defines, used to define both save
* and use register sets.
*
* NOTE: The bit order should HAVE BEEN maintained when saving
* registers on the stack: sp goes at the highest
* address, gp lower on the stack, etc etc
* BUT NOONE CARES ABOUT DEBUGGERS AT MIPS
*/
#define IM_EXC 0x80000000
#define IM_SP 0x40000000
#define IM_GP 0x20000000
#define IM_AT 0x10000000
#define IM_T12 0x08000000
# define IM_PV IM_T4
#define IM_RA 0x04000000
#define IM_T11 0x02000000
# define IM_AI IM_T3
#define IM_T10 0x01000000
#define IM_T9 0x00800000
#define IM_T8 0x00400000
#define IM_A5 0x00200000
#define IM_A4 0x00100000
#define IM_A3 0x00080000
#define IM_A2 0x00040000
#define IM_A1 0x00020000
#define IM_A0 0x00010000
#define IM_S6 0x00008000
#define IM_S5 0x00004000
#define IM_S4 0x00002000
#define IM_S3 0x00001000
#define IM_S2 0x00000800
#define IM_S1 0x00000400
#define IM_S0 0x00000200
#define IM_T7 0x00000100
#define IM_T6 0x00000080
#define IM_T5 0x00000040
#define IM_T4 0x00000020
#define IM_T3 0x00000010
#define IM_T2 0x00000008
#define IM_T1 0x00000004
#define IM_T0 0x00000002
#define IM_V0 0x00000001
#define FM_T15 0x40000000
#define FM_T14 0x20000000
#define FM_T13 0x10000000
#define FM_T12 0x08000000
#define FM_T11 0x04000000
#define FM_T10 0x02000000
#define FM_T9 0x01000000
#define FM_T8 0x00800000
#define FM_T7 0x00400000
#define FM_A5 0x00200000
#define FM_A4 0x00100000
#define FM_A3 0x00080000
#define FM_A2 0x00040000
#define FM_A1 0x00020000
#define FM_A0 0x00010000
#define FM_T6 0x00008000
#define FM_T5 0x00004000
#define FM_T4 0x00002000
#define FM_T3 0x00001000
#define FM_T2 0x00000800
#define FM_T1 0x00000400
#define FM_S7 0x00000200
#define FM_S6 0x00000100
#define FM_S5 0x00000080
#define FM_S4 0x00000040
#define FM_S3 0x00000020
#define FM_S2 0x00000010
#define FM_S1 0x00000008
#define FM_S0 0x00000004
#define FM_T0 0x00000002
#define FM_V1 FM_T0
#define FM_V0 0x00000001
/* Pull in PAL "function" codes. */
#include <machine/pal.h>
/*
* System call glue.
*/
#define SYSCALLNUM(name) \
___CONCAT(SYS_,name)
#define CALLSYS_NOERROR(name) \
ldiq v0, SYSCALLNUM(name); \
call_pal PAL_OSF1_callsys
/*
* Load the global pointer.
*/
#define LDGP(reg) \
ldgp gp, 0(reg)
/*
* WEAK_ALIAS: create a weak alias (ELF only).
*/
#ifdef __ELF__
#define WEAK_ALIAS(alias,sym) \
.weak alias; \
alias = sym
#endif
/*
* Kernel RCS ID tag and copyright macros
*/
#ifdef _KERNEL
#ifdef __ELF__
#define __KERNEL_SECTIONSTRING(_sec, _str) \
.section _sec ; .asciz _str ; .text
#else /* __ELF__ */
#define __KERNEL_SECTIONSTRING(_sec, _str) \
.data ; .asciz _str ; .align 3 ; .text
#endif /* __ELF__ */
#define __KERNEL_RCSID(_n, _s) __KERNEL_SECTIONSTRING(.ident, _s)
#define __KERNEL_COPYRIGHT(_n, _s) __KERNEL_SECTIONSTRING(.copyright, _s)
#ifdef NO_KERNEL_RCSIDS
#undef __KERNEL_RCSID
#define __KERNEL_RCSID(_n, _s) /* nothing */
#endif
#endif /* _KERNEL */