Copyright © 2001 by Edouard G. Parmelan
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
| port-kaffe 0.2 |
| August 30, 2001 |
I had port JIT engine to Alpha Tru64 and GNU/Linux Alpha in the past and I know how it's difficult to understand correctly intrp and JIT engines with only sources as documentation. I had write this document latter while I was porting intrp engine to Darwin (Mac OS X) operating system. In the same time I was writing JIT back-end for PowerPC.
This document is written in SGML DocBook with GNU Emacs and PSGML major mode. Source of this document may be found in Kaffe CVS Tree or in my Kaffe repository.
If you find some bullets in this document, send an email to <egp@free.fr>. All comments are welcome. If you want to fix typo or grammar use SGML sources only and send me "diff -u" result. Never fill-paragraph NOR reformat them.
Preview current working draft here: http://egp.free.fr/port-kaffe/port-kaffe.html.
Preview older draft here: http://egp.free.fr/port-kaffe.
Others persons have already written documents on this subject. I some time peek phrases, sections or inspiration from them.
Kiyo Inaba, "What is trampoline code in Kaffe?", Aug 1998.
Kiyo Inaba, "How sysdepCallMethod works?", Jul 1998.
Samuel K. Sanseri <sanseri@cs.pdx.edu>, "Porting Kaffe to the IA-64 Architecture", Feb 2000.
The first step to port Kaffe to a new platform or new processor family is to port intrp engine. Then As soon as intrp engine works, you can port JIT engine (see Chapter 3). The biggest task will be to write JIT back-end for your processor family (see Chapter 4).
I will try to covers all these tasks in this document.
Quick presentation of all configuration files for a new platform.
Configuring unix-jthreads subsystem.
Locks subsystem.
Writing sysdepCallMethod() function.
Build intrp engine.
This shell script maps configure's variables $host_cpu and $host_os to Kaffe cananical forms $Khost_os and $Khost_os. These variables define access paths to cpu family and platform configuration files.
Optional Makefile fragments required for this cpu family.
Common definitions for all platforms of this cpu family.
Common thread definitions for all platforms of this cpu family.
configure's fragment for this platform.
It may holds specials $CFLAGS add-ons and cross-compile definitions.
Platform dependent header and functions.
File md.h typically includes $Khost_cpu/common.h and $Khost_cpu/thread.h and defines SP_OFFSET macro.
Fields inside classe objects must follow the alignment constraints of the C calling conventions. If alignment of type TYPE is not sizeof(TYPE) you must define macro ALIGNMENT_OF_SIZE(SIZE) in file config/$Khost_cpu/common.h.
The small C program developers/alignment_of_size.c may helps you to discover correct alignment. Simply compiles it and runs it.
Sources of threads subsystems are located into directory kaffe/kaffevm/systems/.
The common threads subsystem is unix-jthread. It uses setjmp() and longjmp() functions. In order to use it you must provide stack pointer offset into jmp_env.
The small C program developers/sp_offset.c may helps you to discover SP_OFFSET. Simply compiles it and runs it. It may leaves core file in you current directory.
Some platforms need to setup Frame-Pointer register when creating a new thread stack. In this case you must provide his offset FP_OFFSET into jmp_env.
Macros SP_OFFSET and FP_OFFSET should be defined in file config/$Khost_cpu/$Kost_os/md.h.
Define the macro THREADSTACKSIZE in file config/$Khost_cpu/thread.h to the size in bytes of each thread's stack. This size may depends on INTERPRETER defined as intrp engine will need greater stack size than JIT engine. Commun values are 64K for intrp engine and 32K for JIT engine.
You may want to use another threads subsystem specific to your platform. It is possible but it's not cover by this document. Read files FAQ/FAQ.jsignal and FAQ/FAQ.locks.
To select another threads subsystem, configure with option --with-threads=thread-subsystem.
Kaffe Fast Locking scheme (read FAQ/FAQ.locks) need a macro to atomic compare and exchange a lock address. This macro COMPARE_AND_EXCHANGE() must be implemented in assembler.
Macro COMPARE_AND_EXCHANGE() should be define in file config/$Khost_cpu/common.h. It is only used into file kaffe/kaffevm/locks.c.
If you can't implement it but have an atomic exchange instruction, defines macro ATOMIC_EXCHANGE() as in Sparc port.
Otherwise, fall back to plain C implementations as in MIPS I port. You should note that it will fail on a multi-processors machine.
Function sysdepCallMethod() setups standard registers and stack parameters for your ABI. It obeys to the C calling conventions of your platform.
It makes a call to a native or Java (JIT) method. This assembly code should build a standard C call using the passed call information. By its nature this is highly processor specific. This function is mandatory for both JIT and Interpreter (since stubs have now been deprecated).
It should be implemented in file config/$Khost_cpu/sysdepCallMethod.h.
The sysdepCallMethod() macro takes a single argument of type callMethodInfo* that describes where the parameters are, where the return value should go and what the signature of the method is.
The function sysdepCallMethod() is only used by functions callMethodA() and callMethodV() in file kaffe/kaffevm/support.c.
The followings macros control the construction of callMethodInfo structure. Define or not define some of them may help you to implements function sysdepCallMethod().
This define causes all types to occupy only one slot in callargs, but not affecting their callsizes, that can still be used to distinguish among types. It avoids introducing unused slots after jlongs and jdoubles.
NO_HOLES is incompatible with ALIGN_AT_64bits.
It causes all integer arguments to be promoted to jlong, and all jfloats to be promoted to jdouble, unless explicitly overridden. It implies NO_HOLES, unless explicitly defined otherwise.
If PROMOTE_jint2jlong is enabled, all integer values are to be passed as jlongs. It is only set by PROMOTE_TO_64bits.
If PROMOTE_jfloat2jdouble is enabled, jfloats are to be passed as jdoubles. Note that, when a jfloat is promoted, its calltype will be marked as 'D'. No known port uses this. In fact, alpha must explicitly set it to 0, to prevent PROMOTE_TO_64bits from enabling it.
This causes all 64bit arguments to be aligned at even arguments. If a jlong or jdouble appears as on odd argument, a place-holder will be introduced.
ALIGN_AT_64bits is incompatible with NO_HOLES.
The callMethodInfo structure describes the information necessary to invoke a native or just-in-time compiled method.
jvalue is a union defined in include/jtypes.h. It corresponds to an entry on the Java stack. The suffixes i, j, b, c, s, l, f, d access the corresponding element of (Java) type int, long, boolean, char, short, ref, float, and double.
args is an array containing the arguments passed to the function. It corresponds to the Java stack and has nrargs valid entries with the following property:
If two adjacent slots on the Java stack are combined to a 64bit value, it will also use two array entries, and not one. However, the first entry will contain the 64bit value (in j or d, depending on the type), and the second entry will be undefined. This allows for easier access, while preserving indexing. Thus, some array entries will have 0, some 32 and some 64 bits of valid data in them. The callsize array says which one it is.
callsize[i] may be 0, 1, or 2, depending on the number of valid bits in args[i]. Similarly, calltype[i] contains the signature type of the argument in args[i] ('J', 'F', etc.)
To simplify 32 bit assembly code, we copy the last 32 bits of a 64 bit arg into the next slot. This allows you to treat args as an array of 32 bit values. This simplification also makes a C version of sysdepCallMethod() more viable.
Note that "callsize[i] == 2 iff callsize[i+1] == 0" -- this property can also be exploited by function sysdepCallMethod().
function is a pointer to the method to be invoked.
retsize and rettype have the same value ranges as callsize[i] and calltype[i], except they correspond to the return value. The function sysdepCallMethod() must store the return value in the proper type at *ret.
If libffi handle your platform, you can use it to implements function sysdepCallMethod(). But it's better to implement it as described bellow.
Configure Kaffe with option --with-libffi explicitly in order to use libffi.
Kaffe use GNU libtool to build dynamic libraries and modules. If it is not able to create them, configure Kaffe with options --with-staticlib and --with-staticvm.
Before port JIT engine, Kaffe intrp engine must work on your platform (see Chapter 2).
If JIT back-end exists for your cpu family, porting JIT engine to your platform will be a simple task.
If your platform use another C calling convensions (ABI) than those handled by JIT back-end of your cpu family you must change it to handle your ABI (see Chapter 4).
Quick presentation of JIT engine configuration files.
NullPointerException, ArithmeticException and signals.
Flush contents of data and/or instruction cache.
Master JIT back-end configuration file for this cpu family.
JIT back-end definitions and functions for this cpu family.
Platform dependent JIT/JIT3 header.
It includes $Khost_cpu/jit.h and defines EXCEPTIONPROTO and EXCEPTIONFRAME macros.
To handle NullPointerException and ArithmeticException Kaffe JIT engine computes Stack-Frame and Program-Counter from various signals context (SIGSEGV, SIGBUS, SIGFPE).
Macro EXCEPTIONPROTO is the function prototype for signal handlers. It must declare sig as signal number parameter. Others platform specific parameters are use transparently but commun name for signal context is ctx.
Macro EXCEPTIONFRAME(frame, ctx) computes exception frame frame from signal context ctx. Parameter frame is a pointer of type exceptionFrame defined in file config/$Khost_cpu/jit.h. This macro may use other parameters defined by EXCEPTIONPROTO.
Some cpu family require to flush contents of data and/or instruction cache before executing new generated code.
In this case, macro FLUSH_DCACHE(start, end) must be defined in file config/$Khost_cpu/$Khost_os/jit3-md.h. Else, this empty macro is defined in file config/$Khost_cpu/jit.h.
Before write new JIT back-end, Kaffe intrp engine must work on your platform (see Chapter 2).
In order to port JIT back-end, you must understand some parts of JIT engine.
Quick presentation of JIT back-end configuration files.
Quick description of JIT engine.
All JIT back-end functions.
buildStackTrace() and stack inspection.
retrieving lock object from a given exception frame.
Function trampoline.
To write new JIT back-end, you must implements the following files:
Master JIT back-end configuration file for this cpu family.
It contains Exception handling information, Method dispatch, Register management information, Opcode generation, Slot management information
Implementation of trampoline function CPU_do_fixup_trampoline().
This file is the main implementation of the JIT back-end. It contains all back-end functions with special marker define_inst(function_name, internal_name).
This file contains definition of all JIT back-end functions. There are in fact macro HAVE_function_name define to back-end internal-name.
Kaffe JIT engine translates on the fly Java methods into native code. It assumes each methods in class dispatch tables are natives. This allows common method invocations in functions callMethodA() and callMethodV().
In fact, Java method entries in dispatch tables are replaced by trampoline functions. First time a method is invoked, his trampoline code is transparently called before real method code is executed.
The task of the trampoline code is to translate Java method into native code, to replace dispatch table entry with newly translated method and to jump into it.
The common function soft_fixup_trampoline() in file kaffe/kaffevm/soft.c calls translator, replaces dispatch table entry and returns translated method. The trampoline code is only a glue to call it and jump into translated method.
The common function buildTrampoline() in file kaffe/kaffevm/classMethod.c allocates a methodTrampoline variable per Java method and initializes it with a call to macro FILL_IN_TRAMPOLINE(). This type and this macro are defined in file config/$Khost_cpu/jit.h.
This structure start with an array of native code and two pointers, meth and where.
Macro FILL_IN_TRAMPOLINE() initializes trampoline tramp for method meth. The parameter where is the address in dispatch table.
It setups native code to make a non standard call to assembler function CPU_do_fixup_trampoline().
This assembler function, implemented into file config/$Khost_cpu/trampolines.c, saves standard call parameters registers, builds a correct stack frame to call C function soft_fixup_trampoline(). Then it restores parameters registers, clean up stack frame and jump into translated method.
This macro defines the parameters list of function soft_fixup_trampoline().
This macro initialize local variable meth and where from parameters to match same fields of current trampoline.
Function spill_TYPE() spills TYPE register seq_slot(0) into its assigned frame location offset seq_slot(1).
It's roughly the same as function store_offsetTYPE().
int o = const_int(1); int r = sreg_TYPE(0); *(TYPE*)($fp + o) = $r;
List of functions: spill_int(), spill_ref(), spill_long(), spill_float(), spill_double()
Function reload_TYPE() reloads TYPE register seq_slot(0) from given frame location offset seq_slot(1).
It's roughly the same as function load_offsetTYPE().
int o = const_int(1); int r = lreg_TYPE(0); $r = *(TYPE*)($fp + o);
List of functions: reload_int() reload_ref() reload_long() reload_float() reload_double()
Required if defined(STACK_LIMIT) and check_stack_limit_constpool() is not defined. See Section 4.5.1.
label *stackoverflow = const_label(2);
int stacklimit = rreg_ref(1);
if ($sp exceeds $stacklimit)
call stackoverflow
Required if defined(STACK_LIMIT) and check_stack_limit() is not defined. See Section 4.5.1.
label *stackoverflow = const_label(2);
int stacklimit = rreg_ref(1);
if ($sp exceeds $stacklimit)
call stackoverflow
Optional
Inlined version of lockObject().
If missing, replaced by soft_call(lockObject).
Optional
Inlined version of unlockObject().
If missing, replaced by soft_call(unlockObject).
Optional
Move contents of register seq_slot(2) into register seq_slot(0).
int r = rreg_TYPE(2); int w = wreg_TYPE(0); $w = $r;
move_int() move_ref() move_long() move_float() move_double()
Optional
Require macro HAVE_move_TYPE_const_rangecheck()
Move constant of seq_slot(2) into register seq_slot(0).
type val = const_TYPE(2); int w = wreg_TYPE(0); $w = val;
Warning: test -0.0 and +0.0 with bit sign.
move_int_const() move_ref_const() move_long_const() move_float_const() move_double_const()
Optional
Move content of 32bit slot seq_slot(2) into slot seq_slot(0).
May be defined as an alias to move_int().
Internal name: movea_RxR.
TODO
Optional
Not used yet.
Move content of 64bit slot seq_slot(2) into slot seq_slot(0).
TODO
Optional
Not need if all load_constpool_TYPE() are defined.
Move address of constant label seq_slot(2) into register seq_slot(0). Final constant address will be compute later.
label *l = const_label(2); int w = wreg_reg(0); l->type |= Lhow-to-update-me; l->at = CODEPC; $w = l;
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 + $r2;
add_int() add_ref() add_long() add_float() add_double()
Optional
Optimize add_TYPE().
Require macro add_TYPE_const_rangecheck().
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r + o;
add_int_const() add_ref_const() add_long_const()
Optional
Required if add_long() is not implemented.
int r2 = rreg_int(2); int r1 = rreg_int(1); int w = wreg_int(0); $w = $r1 + $r2 with carry;
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 - $r2;
sub_int() sub_long() sub_float() sub_double()
Optional
Optimize sub_TYPE().
Require macro sub_TYPE_const_rangecheck().
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r - o;
sub_int_const() sub_long_const()
Optional
Required if sub_long() and set_lt_int() are not implemented.
int r2 = rreg_int(2); int r1 = rreg_int(1); int w = wreg_int(0); $w = $r1 - $r2 with carry;
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 * $r2;
mul_int() mul_long() mul_float() mul_double()
Optional
Optimize mul_TYPE().
Require macro mul_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r * o;
mul_int_const() mul_long_const()
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 / $r2;
div_int() div_long() div_float() div_double()
Optional
Optimize div_TYPE().
Require macro div_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r / o;
div_int_const()
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 % $r2;
rem_int() rem_long()
Optional
Optimize rem_TYPE().
Require macro rem_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r % o;
rem_int_const()
Optional
int r = rreg_TYPE(2); int w = wreg_TYPE(0); $w = - $r;
neg_int() neg_long() neg_float() neg_double()
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 & $r2;
and_int() and_long()
Optional
Optimize and_TYPE().
Require macro and_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r & o;
and_int_const() and_long_const()
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 | $r2;
or_int() or_long()
Optional
Optimize or_TYPE().
Require macro or_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r | o;
or_int_const() or_long_const()
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 ^ $r2;
xor_int() xor_long()
Optional
Optimize xor_TYPE().
Require macro xor_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r ^ o;
xor_int_const() xor_long_const()
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 << $r2;
lshl_int() lshl_long()
Optional
Optimize lshl_TYPE().
Require macro lshl_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r << o;
lshl_int_const() lshl_long_const()
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 >> $r2;
ashr_int() ashr_long()
Optional
Optimize ashr_TYPE().
Require macro ashr_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r >> o;
ashr_int_const() ashr_long_const()
Optional
int r2 = rreg_TYPE(2); int r1 = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r1 >>> $r2;
lshr_int() lshr_long()
Optional
Optimize lshr_TYPE().
Require macro lshr_TYPE_const_rangecheck()
type o = const_TYPE(2); int r = rreg_TYPE(1); int w = wreg_TYPE(0); $w = $r >>> o;
lshr_int_const() lshr_long_const()
Optional
int r = rreg_ref(2); int w = wreg_TYPE(0); $w = *(type*)$r;
load_int() load_ref() load_long() load_float() load_double() load_byte() load_char() load_short()
Optional
If not present, define functions move_label_const() and load_TYPE().
Load constant value from constpool.
label *val = const_label(2); int w = wreg_TYPE(0); l->type |= Lhow-to-update-me; l->at = CODEPC; $w = *(TYPE *) (constpool[val->to]);
load_constpool_int() load_constpool_ref() load_constpool_long() load_constpool_double() load_constpool_float()
Optional
Require macro load_offset_TYPE_rangecheck()
int o = const_int(2); int r = rreg_ref(1); int w = wreg_TYPE(0); $w = *(type*)($r + o);
load_offset_int() load_offset_ref() load_offset_long() load_offset_float() load_offset_double() load_offset_byte() load_offset_char() load_offset_short()
Optional
type *a = const_ref(2); int w = sreg_TYPE(0); $w = *a;
load_addr_int() load_addr_ref() load_addr_long() load_addr_float() load_addr_double() load_addr_byte() load_addr_char() load_addr_short()
Optional
int o = const_int(3); int idx = rreg_int(2); int r = rreg_ref(1); int w = wreg_TYPE(0); $w = ((type*)($r + o))[idx];
load_offset_scaled_int() load_offset_scaled_ref() load_offset_scaled_long() load_offset_scaled_float() load_offset_scaled_double() load_offset_scaled_byte() load_offset_scaled_char() load_offset_scaled_short()
Optional
Alpha only ?
Use for TABLESWITCH and LOOKUPSWITCH.
Special form of load_ref().
Optional
int r = rreg_TYPE(2); int w = rreg_ref(1); *(type*)$w = $r;
store_int() store_ref() store_long() store_float() store_double() store_byte() store_char() store_short()
Optional
Require macro store_offset_TYPE_rangecheck()
int o = const_int(2); int w = rreg_ref(1); int r = rreg_TYPE(0); *(type*)($w + o) = $r;
store_offset_int() store_offset_ref() store_offset_long() store_offset_float() store_offset_double() store_offset_byte() store_offset_char() store_offset_short()
Optional
type val = const_TYPE(2); int o = const_int(1); int w = rreg_ref(0); *(type*)($w + o) = val;
store_const_offset_int() store_const_offset_byte()
Optional
type *a = const_ref(2); int r = rreg_TYPE(1); *a = $r;
store_addr_int() store_addr_ref() store_addr_long() store_addr_float() store_addr_double() store_addr_byte() store_addr_char() store_addr_short()
Optional
int o = const_int(3); int r = rreg_TYPE(2); int idx = rreg_int(1); int w = rreg_ref(0); ((type*)($w + o))[idx] = $r;
store_offset_scaled_int() store_offset_scaled_ref() store_offset_scaled_long() store_offset_scaled_float() store_offset_scaled_double() store_offset_scaled_byte() store_offset_scaled_char() store_offset_scaled_short()
Optional
type val = const_TYPE(3); int o = const_int(2); int idx = rreg_int(1); int w = rreg_ref(0); ((type*)($w + o))[idx] = val;
store_const_offset_scaled_int() store_const_offset_scaled_byte()
WRITE-ME: PUSHARG_FORWARDS kaffe/kaffevm/jni.c kaffe/kaffevm/jit3/icode.c
Optional
TODO
pusharg_int() pusharg_ref() pusharg_long() pusharg_float() pusharg_double()
Optional
Require macro pusharg_TYPE_const_rangecheck()
TODO
pusharg_int_const() pusharg_ref_const()
Optional
Require macro cbranch_TYPE_const_rangecheck()
TODO
cbranch_int_const() cbranch_ref_const()
Optional
TODO
return_int() return_ref() return_long() return_float() return_double()
Optional
TODO
returnarg_int() returnarg_ref() returnarg_long() returnarg_float() returnarg_double()
Optional
Required if cbranch_TYPE_const() is missing.
Require macro cmp_TYPE_const_rangecheck()
TODO
cmp_int_const() cmp_ref_const()
Optional
If missing, replaced by soft_fcmpl() and soft_dcmpl().
TODO
cmpl_float() cmpl_double()
Optional
TODO
cvt_int_long() cvt_int_float() cvt_int_double() cvt_long_float() cvt_long_double() cvt_float_int() cvt_float_long() cvt_float_double() cvt_double_int() cvt_double_long() cvt_double_float() cvt_int_byte() cvt_int_short()
TODO
For stack register. As soon as read, content is discared.
Register is preserved across function call, it's not necessary to save it on call.
Function global register.
TODO
If this macro is defined the result of function jthread_stacklimit() is passed as an extra argument to all methods. This macro return the slot offset of this extra argument.
One of the functions check_stack_limit() and check_stack_limit_constpool() must be defined. See Section 4.3.2.4 and Section 4.3.2.5
Source file developers/jit-icode.c may helps you to discover correct implementation of various JIT back-end functions. Compile it with -S option and read jit-icode.s or compile it with -g option and disassemble various functions with gdb or what ever debugger you have.
Script developers/kaffe-test.
Class VMDebug.
-vmdebug jit,morejit
/* jit-icode.c
* $Id: jit-icode.c,v 1.3 2001/08/30 21:17:16 egp Exp $
*
* Copyright (c) 2001
* Edouard G. Parmelan. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
typedef long jint;
typedef unsigned long ujint;
typedef long long jlong;
typedef unsigned long long ujlong;
typedef float jfloat;
typedef double jdouble;
typedef signed char jbyte;
typedef short jshort;
typedef unsigned short jchar;
typedef unsigned char* uintp;
/* Register spills and reloads */
/* spill_TYPE() see store_offset_TYPE() */
/* reload_TYPE() see load_offset_TYPE() */
/* Prologues and epilogues */
extern int do_some_job(int a0, int a1, int a2, int a3);
extern int do_other_job(int a0, int a1, int a2, int a3,
int a4, int a5, int a6, int a7,
int a8, int a9, int a10, int a11,
int a12, int a13, int a14, int a15);
int prologue_epilogue_4(int a0, int a1, int a2, int a3)
{
int v0;
v0 = do_some_job (a0, a1, a2, a3);
return v0;
}
int prologue_epilogue_8(int a0, int a1, int a2, int a3,
int a4, int a5, int a6, int a7)
{
int v0, v1;
v0 = do_some_job (a0, a1, a2, a3);
v1 = do_some_job (a4, a5, a6, a7);
return v0 + v1;
}
int prologue_epilogue_12(int a0, int a1, int a2, int a3,
int a4, int a5, int a6, int a7,
int a8, int a9, int a10, int a11)
{
int v0, v1, v2;
v0 = do_some_job (a0, a1, a2, a3);
v1 = do_some_job (a4, a5, a6, a7);
v2 = do_some_job (a8, a9, a10, a11);
return v0 + v1 + v2;
}
int prologue_epilogue_16(int a0, int a1, int a2, int a3,
int a4, int a5, int a6, int a7,
int a8, int a9, int a10, int a11,
int a12, int a13, int a14, int a15)
{
int v0, v1, v2, v3;
v0 = do_some_job (a0, a1, a2, a3);
v1 = do_some_job (a4, a5, a6, a7);
v2 = do_some_job (a8, a9, a10, a11);
v3 = do_some_job (a12, a13, a14, a15);
return v0 + v1 + v2 + v3;
}
int prologue_epilogue_16_long(int a0, int a1, int a2, int a3,
int a4, int a5, int a6, int a7,
int a8, int a9, int a10, int a11,
int a12, int a13, int a14, int a15)
{
int v0, v1, v2, v3, v4;
v0 = do_some_job (a0, a1, a2, a3);
v1 = do_some_job (a4, a5, a6, a7);
v2 = do_some_job (a8, a9, a10, a11);
v3 = do_some_job (a12, a13, a14, a15);
v4 = do_other_job (a0, a1, a2, a3,
a4, a5, a6, a7,
a8, a9, a10, a11,
a12, a13, a14, a15);
return do_some_job (v0, v1, v2, v3) + v4;
}
/* Moves */
#define move_int_const(NAME, val) \
jint move_int_const_##NAME(void) { return val; }
move_int_const(0, 0);
move_int_const(32767, 32767)
move_int_const(m32768, -32768)
move_int_const(0x7fff, 0x7fff)
move_int_const(m0x8000, -0x8000)
move_int_const(0x8000, 0x8000)
move_int_const(65535, 65535)
move_int_const(65536, 65536)
/* Arithmetic operators */
#define add_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a + b; }
add_TYPE(add_int, jint);
// add_TYPE(add_ref, void*);
add_TYPE(add_long, jlong);
add_TYPE(add_float, jfloat);
add_TYPE(add_double, jdouble);
#define sub_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a - b; }
sub_TYPE(sub_int, jint);
// sub_TYPE(sub_ref, void*);
sub_TYPE(sub_long, jlong);
sub_TYPE(sub_float, jfloat);
sub_TYPE(sub_double, jdouble);
#define mul_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a * b; }
mul_TYPE(mul_int, jint);
mul_TYPE(mul_long, jlong);
mul_TYPE(mul_float, jfloat);
mul_TYPE(mul_double, jdouble);
#define div_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a / b; }
div_TYPE(div_int, jint);
div_TYPE(div_long, jlong);
div_TYPE(div_float, jfloat);
div_TYPE(div_double, jdouble);
#define rem_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a % b; }
rem_TYPE(rem_int, jint);
rem_TYPE(rem_long, jlong);
#define neg_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a) { return -a; }
neg_TYPE(neg_int, jint);
neg_TYPE(neg_long, jlong);
neg_TYPE(neg_float, jfloat);
neg_TYPE(neg_double, jdouble);
/* Logical operators */
#define and_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a & b; }
and_TYPE(and_int, jint);
and_TYPE(and_long, jlong);
#define or_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a | b; }
or_TYPE(or_int, jint);
or_TYPE(or_long, jlong);
#define xor_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a ^ b; }
xor_TYPE(xor_int, jint);
xor_TYPE(xor_long, jlong);
#define lshl_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a << b; }
lshl_TYPE(lshl_int, jint);
lshl_TYPE(lshl_long, jlong);
#define lshl_int_const(NAME, VAL) \
jint lshl_int_const_##NAME(jint a) { return a << VAL; }
lshl_int_const(1, 1)
lshl_int_const(2, 2)
lshl_int_const(3, 3)
lshl_int_const(4, 4)
lshl_int_const(5, 5)
lshl_int_const(6, 6)
lshl_int_const(7, 7)
lshl_int_const(8, 8)
lshl_int_const(9, 9)
lshl_int_const(10, 10)
lshl_int_const(11, 11)
lshl_int_const(12, 12)
lshl_int_const(13, 13)
lshl_int_const(14, 14)
lshl_int_const(15, 15)
lshl_int_const(16, 16)
lshl_int_const(17, 17)
lshl_int_const(18, 18)
lshl_int_const(19, 19)
lshl_int_const(20, 20)
lshl_int_const(21, 21)
#define ashr_TYPE(NAME, TYPE) \
TYPE NAME (TYPE a, TYPE b) { return a >> b; }
ashr_TYPE(ashr_int, jint);
ashr_TYPE(ashr_long, jlong);
#define lshr_TYPE(NAME, TYPE) \
TYPE NAME (u##TYPE a, TYPE b) { return a >> b; }
lshr_TYPE(lshr_int, jint);
lshr_TYPE(lshr_long, jlong);
/* Load and store */
#define load_TYPE(NAME, TYPE) \
TYPE NAME (uintp r) { return *(TYPE *)r; }
load_TYPE(load_int, jint);
load_TYPE(load_ref, void*);
load_TYPE(load_long, jlong);
load_TYPE(load_float, jfloat);
load_TYPE(load_double, jdouble);
load_TYPE(load_byte, jbyte);
load_TYPE(load_char, jchar);
load_TYPE(load_short, jshort);
// load_constpool_TYPE
#define load_offset_TYPE(NAME, TYPE) \
TYPE NAME (uintp r, int o) { return *(TYPE *)(r + o); }
load_offset_TYPE(load_offset_int, jint);
load_offset_TYPE(load_offset_ref, void*);
load_offset_TYPE(load_offset_long, jlong);
load_offset_TYPE(load_offset_float, jfloat);
load_offset_TYPE(load_offset_double, jdouble);
load_offset_TYPE(load_offset_byte, jbyte);
load_offset_TYPE(load_offset_char, jchar);
load_offset_TYPE(load_offset_short, jshort);
#define load_addr_TYPE(NAME, TYPE) \
TYPE NAME (void) { return *(TYPE *)(0x87654321); }
load_addr_TYPE(load_addr_int, jint);
load_addr_TYPE(load_addr_ref, void*);
load_addr_TYPE(load_addr_long, jlong);
load_addr_TYPE(load_addr_float, jfloat);
load_addr_TYPE(load_addr_double, jdouble);
load_addr_TYPE(load_addr_byte, jbyte);
load_addr_TYPE(load_addr_char, jchar);
load_addr_TYPE(load_addr_short, jshort);
#define load_offset_scaled_TYPE(NAME, TYPE) \
TYPE NAME (uintp r, int idx, int o) { return ((TYPE *)(r + o))[idx]; }
load_offset_scaled_TYPE(load_offset_scaled_int, jint);
load_offset_scaled_TYPE(load_offset_scaled_ref, void*);
load_offset_scaled_TYPE(load_offset_scaled_long, jlong);
load_offset_scaled_TYPE(load_offset_scaled_float, jfloat);
load_offset_scaled_TYPE(load_offset_scaled_double, jdouble);
load_offset_scaled_TYPE(load_offset_scaled_byte, jbyte);
load_offset_scaled_TYPE(load_offset_scaled_char, jchar);
load_offset_scaled_TYPE(load_offset_scaled_short, jshort);
#define store_TYPE(NAME, TYPE) \
void NAME (TYPE r, uintp w) { *(TYPE *)w = r; }
store_TYPE(store_int, jint);
store_TYPE(store_ref, void*);
store_TYPE(store_long, jlong);
store_TYPE(store_float, jfloat);
store_TYPE(store_double, jdouble);
store_TYPE(store_byte, jbyte);
store_TYPE(store_char, jchar);
store_TYPE(store_short, jshort);
#define store_offset_TYPE(NAME, TYPE) \
void NAME (TYPE r, uintp w, int o) { *(TYPE *)(w + o) = r; }
store_offset_TYPE(store_offset_int, jint);
store_offset_TYPE(store_offset_ref, void*);
store_offset_TYPE(store_offset_long, jlong);
store_offset_TYPE(store_offset_float, jfloat);
store_offset_TYPE(store_offset_double, jdouble);
store_offset_TYPE(store_offset_byte, jbyte);
store_offset_TYPE(store_offset_char, jchar);
store_offset_TYPE(store_offset_short, jshort);
// store_addr_TYPE
#define store_offset_scaled_TYPE(NAME, TYPE) \
void NAME (TYPE r, uintp w, int idx, int o) { ((TYPE *)(w + o))[idx] = r; }
store_offset_scaled_TYPE(store_offset_scaled_int, jint);
store_offset_scaled_TYPE(store_offset_scaled_ref, void*);
store_offset_scaled_TYPE(store_offset_scaled_long, jlong);
store_offset_scaled_TYPE(store_offset_scaled_float, jfloat);
store_offset_scaled_TYPE(store_offset_scaled_double, jdouble);
store_offset_scaled_TYPE(store_offset_scaled_byte, jbyte);
store_offset_scaled_TYPE(store_offset_scaled_char, jchar);
store_offset_scaled_TYPE(store_offset_scaled_short, jshort);
/* Function argument management */
/* Control flow changes */
/* Labels */
/* Comparisons */
/* Conversions */
#define cvt_FROM_TO(NAME, FROM, TO) \
TO NAME(FROM a) { return (TO)a; }
cvt_FROM_TO(cvt_int_long, jint, jlong);
cvt_FROM_TO(cvt_int_float, jint, jfloat);
cvt_FROM_TO(cvt_int_double, jint, jdouble);
cvt_FROM_TO(cvt_long_float, jlong, jfloat);
cvt_FROM_TO(cvt_long_double, jlong, jdouble);
cvt_FROM_TO(cvt_float_int, jfloat, jint);
cvt_FROM_TO(cvt_float_long, jfloat, jlong);
cvt_FROM_TO(cvt_float_double, jfloat, jdouble);
cvt_FROM_TO(cvt_double_int, jdouble, jint);
cvt_FROM_TO(cvt_double_long, jdouble, jlong);
cvt_FROM_TO(cvt_double_float, jdouble, jfloat);
cvt_FROM_TO(cvt_int_byte, jint, jbyte);
cvt_FROM_TO(cvt_int_short, jint, jshort);
/*
* Local variables:
* compile-command: "gcc -O2 -fverbose-asm -S jit-icode.c"
* End:
*/
Version 1.1, March 2000
Copyright (C) 2000 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
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