freebsd-dev/sys/amd64/include/asmacros.h
1997-02-22 09:48:43 +00:00

214 lines
7.6 KiB
C

/*-
* Copyright (c) 1993 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Id$
*/
#ifndef _MACHINE_ASMACROS_H_
#define _MACHINE_ASMACROS_H_
#ifdef KERNEL
#include <sys/cdefs.h>
/* XXX too much duplication in various asm*.h's. */
#define ALIGN_DATA .align 2 /* 4 byte alignment, zero filled */
#ifdef GPROF
#define ALIGN_TEXT .align 4,0x90 /* 16-byte alignment, nop filled */
#else
#define ALIGN_TEXT .align 2,0x90 /* 4-byte alignment, nop filled */
#endif
#define SUPERALIGN_TEXT .align 4,0x90 /* 16-byte alignment, nop filled */
#define GEN_ENTRY(name) ALIGN_TEXT; .globl __CONCAT(_,name); \
__CONCAT(_,name):
#define NON_GPROF_ENTRY(name) GEN_ENTRY(name)
#define NON_GPROF_RET .byte 0xc3 /* opcode for `ret' */
#ifdef GPROF
/*
* __mcount is like mcount except that doesn't require its caller to set
* up a frame pointer. It must be called before pushing anything onto the
* stack. gcc should eventually generate code to call __mcount in most
* cases. This would make -pg in combination with -fomit-frame-pointer
* useful. gcc has a configuration variable PROFILE_BEFORE_PROLOGUE to
* allow profiling before setting up the frame pointer, but this is
* inadequate for good handling of special cases, e.g., -fpic works best
* with profiling after the prologue.
*
* mexitcount is a new function to support non-statistical profiling if an
* accurate clock is available. For C sources, calls to it are generated
* by the FreeBSD extension `-mprofiler-epilogue' to gcc. It is best to
* call mexitcount at the end of a function like the MEXITCOUNT macro does,
* but gcc currently generates calls to it at the start of the epilogue to
* avoid problems with -fpic.
*
* mcount and __mexitcount may clobber the call-used registers and %ef.
* mexitcount may clobber %ecx and %ef.
*
* Cross-jumping makes non-statistical profiling timing more complicated.
* It is handled in many cases by calling mexitcount before jumping. It is
* handled for conditional jumps using CROSSJUMP() and CROSSJUMP_LABEL().
* It is handled for some fault-handling jumps by not sharing the exit
* routine.
*
* ALTENTRY() must be before a corresponding ENTRY() so that it can jump to
* the main entry point. Note that alt entries are counted twice. They
* have to be counted as ordinary entries for gprof to get the call times
* right for the ordinary entries.
*
* High local labels are used in macros to avoid clashes with local labels
* in functions.
*
* Ordinary `ret' is used instead of a macro `RET' because there are a lot
* of `ret's. 0xc3 is the opcode for `ret' (`#define ret ... ret' can't
* be used because this file is sometimes preprocessed in traditional mode).
* `ret' clobbers eflags but this doesn't matter.
*/
#define ALTENTRY(name) GEN_ENTRY(name) ; MCOUNT ; MEXITCOUNT ; jmp 9f
#define CROSSJUMP(jtrue, label, jfalse) \
jfalse 8f; MEXITCOUNT; jmp __CONCAT(to,label); 8:
#define CROSSJUMPTARGET(label) \
ALIGN_TEXT; __CONCAT(to,label): ; MCOUNT; jmp label
#define ENTRY(name) GEN_ENTRY(name) ; 9: ; MCOUNT
#define FAKE_MCOUNT(caller) pushl caller ; call __mcount ; popl %ecx
#define MCOUNT call __mcount
#define MCOUNT_LABEL(name) GEN_ENTRY(name) ; nop ; ALIGN_TEXT
#define MEXITCOUNT call mexitcount
#define ret MEXITCOUNT ; NON_GPROF_RET
#else /* !GPROF */
/*
* ALTENTRY() has to align because it is before a corresponding ENTRY().
* ENTRY() has to align to because there may be no ALTENTRY() before it.
* If there is a previous ALTENTRY() then the alignment code for ENTRY()
* is empty.
*/
#define ALTENTRY(name) GEN_ENTRY(name)
#define CROSSJUMP(jtrue, label, jfalse) jtrue label
#define CROSSJUMPTARGET(label)
#define ENTRY(name) GEN_ENTRY(name)
#define FAKE_MCOUNT(caller)
#define MCOUNT
#define MCOUNT_LABEL(name)
#define MEXITCOUNT
#endif /* GPROF */
#else /* !KERNEL */
#include "/usr/src/lib/libc/i386/DEFS.h" /* XXX blech */
/*
* In the !KERNEL case, this header is only (ab)used in lib/msun/i387.
* Use it to generate code to select between the generic math functions
* and the i387 ones.
*/
#undef ENTRY
#define ANAME(x) CNAME(__CONCAT(__i387_,x))
#define ASELNAME(x) CNAME(__CONCAT(__arch_select_,x))
#define AVECNAME(x) CNAME(__CONCAT(__arch_,x))
#define GNAME(x) CNAME(__CONCAT(__generic_,x))
/* Don't bother profiling this. */
#ifdef PIC
#define ARCH_DISPATCH(x) \
_START_ENTRY; \
.globl CNAME(x); .type CNAME(x),@function; CNAME(x): ; \
PIC_PROLOGUE; \
movl PIC_GOT(AVECNAME(x)),%eax; \
PIC_EPILOGUE; \
jmpl *(%eax)
#define ARCH_SELECT(x) _START_ENTRY; \
.type ASELNAME(x),@function; \
ASELNAME(x): \
PIC_PROLOGUE; \
call PIC_PLT(CNAME(__get_hw_float)); \
testl %eax,%eax; \
movl PIC_GOT(ANAME(x)),%eax; \
jne 8f; \
movl PIC_GOT(GNAME(x)),%eax; \
8: \
movl PIC_GOT(AVECNAME(x)),%edx; \
movl %eax,(%edx); \
PIC_EPILOGUE; \
jmpl *%eax
#else /* !PIC */
#define ARCH_DISPATCH(x) \
_START_ENTRY; \
.globl CNAME(x); .type CNAME(x),@function; CNAME(x): ; \
jmpl *AVECNAME(x)
#define ARCH_SELECT(x) _START_ENTRY; \
.type ASELNAME(x),@function; \
ASELNAME(x): \
call CNAME(__get_hw_float); \
testl %eax,%eax; \
movl $ANAME(x),%eax; \
jne 8f; \
movl $GNAME(x),%eax; \
8: \
movl %eax,AVECNAME(x); \
jmpl *%eax
#endif /* PIC */
#define ARCH_VECTOR(x) .data; .align 2; \
.globl AVECNAME(x); \
.type AVECNAME(x),@object; \
.size AVECNAME(x),4; \
AVECNAME(x): .long ASELNAME(x)
#ifdef PROF
#define ALTENTRY(x) ENTRY(x); jmp 9f
#define ENTRY(x) ARCH_VECTOR(x); ARCH_SELECT(x); ARCH_DISPATCH(x); \
_START_ENTRY; \
.globl ANAME(x); .type ANAME(x),@function; ANAME(x):; \
call HIDENAME(mcount); 9:
#else /* !PROF */
#define ALTENTRY(x) ENTRY(x)
#define ENTRY(x) ARCH_VECTOR(x); ARCH_SELECT(x); ARCH_DISPATCH(x); \
_START_ENTRY; \
.globl ANAME(x); .type ANAME(x),@function; ANAME(x):
#endif /* PROF */
#ifndef RCSID
#define RCSID(a)
#endif
#endif /* KERNEL */
#endif /* !_MACHINE_ASMACROS_H_ */