mipsel-nec-elf

Toppers/JSP の KZ-Vr4131PCI-01 ターゲットは、GCC の mipsel-nec-elf というターゲットを前提にしているらしいので、とりあえず作ってみた。

http://cvs.sourceforge.jp/cgi-bin/viewcvs.cgi/jsp4cm3/jsp/doc/mips3.txt?rev=1.1
http://cvs.sourceforge.jp/cgi-bin/viewcvs.cgi/jsp4cm3/jsp/doc/gnu_install.txt?rev=1.1

（ただし、binutils-2.13.2.1、gcc-3.3.2、newlib-1.11.0 の環境らしいので、以下の環境で通るかどうかはわからない。)

$ tar zxvf binutils-2.19.tar.gz
$ mkdir build-binutils-mipsel-nec-elf
$ cd build-binutils-mipsel-nec-elf
$ ../binutils-2.19/configure --prefix=/usr/local/mips --target=mipsel-nec-elf --disable-nls
$ make -i
$ make -i install
$ tar zxvf gcc-4.3.2.tar.gz
$ tar zxvf newlib-1.16.0.tar.gz
$ cd gcc-4.3.2.tar.gz
$ ln -s ../newlib-1.16.0/newlib
$ ln -s ../newlib-1.16.0/libgloss
$ cd ..
$ mkdir build-gcc-mipsel-nec-elf
$ cd build-gcc-mipsel-nec-elf
$ ../gcc-4.3.2/configure --with-gmp=/usr/local --with-mpfr=/usr/local --enable-languages=c,c++ --disable-nls --disable-win32-regist
ry --disable-shared --disable-libssp --prefix=/usr/local/mips/ --target=mipsel-nec-elf --disable-multilib --without-fp --disable-li
bmudflap --disable-libstdcxx-pch --with-newlib --with-headers=/home/aloha/work/mips/build/gcc-4.3.2/newlib/libc/include/
$ make
$ make install

重要なのは configure オプションだけなので、展開のところとかは適宜読み替えて適当に。
texinfo 絡みでエラーが出るので、make -i で強制的にビルドとインストールを進めている （他に致命的なエラーがあった場合、ひどい事になる場合もあるので、本当は随時確認しながら無視した方が良い。今回はコケることが最初からわかっているので、最初からエラーを無視 (-i) してビルド & インストールしてる）

mips-unknown-elf gcc with newlib

以前は mips-linux-elf で作ったので、linux に依存するヘッダを要求されてコケた。

linux kernel をビルドすることに拘らなければ、mips-unknown-elf で普通に通った。

newlib-1.16.0 を展開して、gcc-4.3.2/ 以下に newlib-1.6.0/newlib と newlib-1.6.0/libgloss へのシンボリックリンクを張る。

binutils -> gcc -> newlib の順に、以下のように configure ; make ; make install する （別途 build-*** のようなディレクトリを掘って、そこで行う）。

途中で makeinfo がどうこうというエラーが出たら、make -i で無視してビルドを続行する。

$ ../binutils-2.19/configure --prefix=/usr/local/mips --target=mipsel-unknown-elf --disable-nls --without-included-gette
xt

$ ../gcc-4.3.2/configure --with-gmp=/usr/local --with-mpfr=/usr/local --enable-languages=c,c++ --disable-nls --disable-w
in32-registry --disable-shared --without-included-gettext --disable-libssp --prefix=/usr/local/mips/ --target=mipsel-unk
nown-elf --disable-multilib --without-fp --disable-libmudflap --disable-libstdcxx-pch --with-newlib --with-headers=/home
/aloha/work/mips/build/gcc-4.3.2/newlib/libc/include/

$ ../newlib-1.16.0/configure --target=mipsel-unknown-elf --prefix=/usr/loca/mips

（newlib のビルドは gcc と同時に行われるから不要かもしれない。未確認）

できた gcc で、-EB オプションを付けると

$ /usr/local/mips/bin/mipsel-unknown-elf-gcc.exe -EB test.c
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crti.o: compiled for a little endian system and target is big endian
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crti.o: endianness incompatible with that of the selected emulation
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: failed to merge target specific data of file c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crti.o
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtbegin.o: compiled for a little endian system and target is big endian
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtbegin.o: endianness incompatible with that of the selected emulation
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: failed to merge target specific data of file c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtbegin.o
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtend.o: compiled for a little endian system and target is big endian
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtend.o: endianness incompatible with that of the selected emulation
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: failed to merge target specific data of file c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtend.o
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtn.o: compiled for a little endian system and target is big endian
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtn.o: endianness incompatible with that of the selected emulation
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: failed to merge target specific data of file c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/crtn.o
c:/msys/1.0/local/mips/bin/../lib/gcc/mipsel-unknown-elf/4.3.2/../../../../mipsel-unknown-elf/bin/ld.exe: warning: cannot find entry symbol _start; defaulting to 0000000000400050
collect2: ld returned 1 exit status

エラーになってしまう （最後の警告は、crt0.o と ld script を用意してないから当たり前）

これを両方サポートできるようにするために、enable-targets とかでなんとかできるかと思ったけど、結局上手く行かなかった。

VEC

gcc の VEC (vec.[ch]) データ構造は、プリプロセッサを使って C++ の template みたいなことをやってるらしい (C++ 言語のカラクリ とかでも触れられてるけど、cfront 時代の template の実現手法としては比較的ポピュラー)

ほんと GCC は C++ の機能を C で無理やり実装するのが得意だよなぁ。

GCC の MIPS ターゲット

newlib で作ろうとしたら、asm/unistd.h が無いよ！と、明らかに Linux Kernel の header らしきファイルを要求されて上手く行かなかった。

しかたがないので、--disable-libstdc と --disable-libstdcxx で作ってみた (MinGW + MSYS + flex + bison)。

$ ../binutils-2.19/configure --prefix=/usr/local/mips --target=mips-elf --disable-nls --without-included-gettext
...
$ ../gcc-4.3.2/configure --with-gmp=/usr/local --with-mpfr=/usr/local --enable-languages=c,c++ --disable-nls --disable-win32-registry --di
sable-shared --without-x --without-included-gettext --disable-libssp --prefix=/usr/local/mips/ --target=mips-elf --disable-multilib --with
out-fp --disable-libmudflap --disable-libstdc --disable-libstdcxx --disable-libstdcxx-pch --enable-threads --enable-hash-synchronization
...

enable-threads とか enable-hash-synchronizasion は、特に意味が無いようだ。disable-libstdcxx-pch も、たぶんいらない気がする (MinGW では、pch (PreCompiled Header) のテストが通らないから、いつまでたっても gcc が 4 系にならないらしい。ssp (StackSmashingProtector) と pch は disable にしないと、普通の gcc もビルドできない。

$ /usr/local/mips/bin/mips-elf-gcc-4.3.2.exe -v
Using built-in specs.
Target: mips-elf
Configured with: ../gcc-4.3.2/configure --with-gmp=/usr/local --with-mpfr=/usr/local --enable-languages=c,c++ --disable-nls --disable-win32-registry --disable-shared --without-x --without-included-gettext --disable-libssp --prefix=/usr/local/mips/ --target=mips-elf --disable-multilib --without-fp --disable-libmudflap --disable-libstdc --disable-libstdcxx --disable-libstdcxx-pch --enable-threads --enable-hash-synchronization
Thread model: single
gcc version 4.3.2 (GCC)

libgcc の target ごとに使われる関数

libgcc は、乗算や除算など C の言語仕様のうち、CPU が直接サポートしてない機能を補助するために、GCC が勝手にくっ付けるライブラリ。

gcc-4.3.2/gcc/config/arm/t-linux とかを見ると。

LIB1ASMSRC = arm/lib1funcs.asm
LIB1ASMFUNCS = _udivsi3 _divsi3 _umodsi3 _modsi3 _dvmd_lnx

のように、呼ばれる関数が書いてある。

target ごとの設定は t-* とかに書いてあるらしい。

GCC のサンプルバックエンド

Incremental Machine Descriptions for Spim を参考に、gcc-4.3.2 に対応させて作ってみた。
http://github.com/alohakun/gcc-sample-backend/tree/master
最小限の C コードだけに対応したバックエンド。

$ ../bin/gcc-spim.exe -v
Using built-in specs.
Target: spim
Configured with: ../gcc-4.3.2/configure --with-gmp=/usr/local
--with-mpfr=/usr/local --enable-languages=c
--prefix=/home/aloha/test/gcc --target=spim --disable-libgcc
--enable-threads --disable-nls --disable-win32-registry --disable-shared
--without-x --enable-hash-synchronization
--enable-version-specific-runtime-libs --without-included-gettext
--disable-bootstrap --disable-libssp --program-suffix=-spim
--with-as=/usr/local/bin/as --with-ld=/usr/local/bin/ld
Thread model: single
gcc version 4.3.2 (GCC)

$ cat test0.c
void f()
{
L:
goto L;
}

void g()
{
}

$ ../bin/gcc-spim.exe -S -O2 test0.c

$ cat test0.s
.text
.align 2
.globl f
f:
L2: sw $ra, 0($sp)
sw $sp, -4($sp)
sw $fp, -8($sp)
move $fp,$sp
addi $sp, $fp, -44
L3: j L3
.align 2
.globl g
g:
sw $ra, 0($sp)
sw $sp, -4($sp)
sw $fp, -8($sp)
move $fp,$sp
sw $s0, 0($fp)
sw $s1, -4($fp)
sw $s2, -8($fp)
sw $s3, -12($fp)
sw $s4, -16($fp)
sw $s5, -20($fp)
sw $s6, -24($fp)
sw $s7, -28($fp)
addi $sp, $fp, -44
lw $s0, 0($fp)
lw $s1, -4($fp)
lw $s2, -8($fp)
lw $s3, -12($fp)
lw $s4, -16($fp)
lw $s5, -20($fp)
lw $s6, -24($fp)
lw $s7, -28($fp)
move $sp,$fp
lw $fp, -8($sp)
lw $ra, 0($sp)
jr $ra

こんだけでも move や addi が生成されるので、けっこう大きい。

変更ファイル : (spim ターゲットを追加しただけ)

gcc-4.3.2/config.sub
gcc-4.3.2/gcc/config.gcc

追加ファイル :

gcc-4.3.2/gcc/config/spim/spim.md (138 行)
gcc-43.2/gcc/config/spim/spim.h (370 行)
gcc-4.3.2/gcc/config/spim/spim.c (737 行)
gcc-4.3.2/gcc/config/spim/spim-protos.h (52 行)

展開して、--target=spim を指定して、通常通りビルドすればいけるはず (prefix を適当に指定)。
libgcc と as と ld を disable にしてあるので、binutils のインストールもたぶん不要 （もちろん、-S 付けてのアセンブリコード生成までしかできない）

RTL 式

RTL 式は、常にポインタ経由で扱われる　C 構造体 struct rtx 型。

整数、ワイド整数(HOST_WIDE_INT)、C 文字列(char*)、配列を含む S 式。

RTL 式内の C 文字列 "..." は、基本的に C の文字列リテラルと同じだけど、複数行に渡って記述できるように拡張されている。

配列は　[ ... ] という式表現。任意個のポインタを含む。
長さ 0 の配列は作れない。代わりにヌルポインタを使う。
ヌルポインタは (nil) と書く。

GET_CODE (x) で取得、PUT_CODE (x, newcode) で変更できる RTL コードにより、オペランドの数などが決まる。
rtl.def で定義されている列挙体。

gcc-4.3.2/gcc/rtl.def

+ expand sourceview plainprint?

1. /* This file contains the definitions and documentation for the 
2.    Register Transfer Expressions (rtx's) that make up the 
3.    Register Transfer Language (rtl) used in the Back End of the GNU compiler. 
4.    Copyright (C) 1987, 1988, 1992, 1994, 1995, 1997, 1998, 1999, 2000, 2004, 
5.    2005, 2006, 2007 
6.    Free Software Foundation, Inc. 
7.  
8. This file is part of GCC. 
9.  
10. GCC is free software; you can redistribute it and/or modify it under 
11. the terms of the GNU General Public License as published by the Free 
12. Software Foundation; either version 3, or (at your option) any later 
13. version. 
14.  
15. GCC is distributed in the hope that it will be useful, but WITHOUT ANY 
16. WARRANTY; without even the implied warranty of MERCHANTABILITY or 
17. FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License 
18. for more details. 
19.  
20. You should have received a copy of the GNU General Public License 
21. along with GCC; see the file COPYING3.  If not see 
22. <http: www.gnu.org="" licenses="">.  */  
23.   
24.   
25. /* Expression definitions and descriptions for all targets are in this file. 
26.    Some will not be used for some targets. 
27.  
28.    The fields in the cpp macro call "DEF_RTL_EXPR()" 
29.    are used to create declarations in the C source of the compiler. 
30.  
31.    The fields are: 
32.  
33.    1.  The internal name of the rtx used in the C source. 
34.    It is a tag in the enumeration "enum rtx_code" defined in "rtl.h". 
35.    By convention these are in UPPER_CASE. 
36.  
37.    2.  The name of the rtx in the external ASCII format read by 
38.    read_rtx(), and printed by print_rtx(). 
39.    These names are stored in rtx_name[]. 
40.    By convention these are the internal (field 1) names in lower_case. 
41.  
42.    3.  The print format, and type of each rtx->u.fld[] (field) in this rtx. 
43.    These formats are stored in rtx_format[]. 
44.    The meaning of the formats is documented in front of this array in rtl.c 
45.     
46.    4.  The class of the rtx.  These are stored in rtx_class and are accessed 
47.    via the GET_RTX_CLASS macro.  They are defined as follows: 
48.  
49.      RTX_CONST_OBJ 
50.          an rtx code that can be used to represent a constant object 
51.          (e.g, CONST_INT) 
52.      RTX_OBJ 
53.          an rtx code that can be used to represent an object (e.g, REG, MEM) 
54.      RTX_COMPARE 
55.          an rtx code for a comparison (e.g, LT, GT) 
56.      RTX_COMM_COMPARE 
57.          an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED) 
58.      RTX_UNARY 
59.          an rtx code for a unary arithmetic expression (e.g, NEG, NOT) 
60.      RTX_COMM_ARITH 
61.          an rtx code for a commutative binary operation (e.g,, PLUS, MULT) 
62.      RTX_TERNARY 
63.          an rtx code for a non-bitfield three input operation (IF_THEN_ELSE) 
64.      RTX_BIN_ARITH 
65.          an rtx code for a non-commutative binary operation (e.g., MINUS, DIV) 
66.      RTX_BITFIELD_OPS 
67.          an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT) 
68.      RTX_INSN 
69.          an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN) 
70.      RTX_MATCH 
71.          an rtx code for something that matches in insns (e.g, MATCH_DUP) 
72.      RTX_AUTOINC 
73.          an rtx code for autoincrement addressing modes (e.g. POST_DEC) 
74.      RTX_EXTRA 
75.          everything else 
76.  
77.    All of the expressions that appear only in machine descriptions, 
78.    not in RTL used by the compiler itself, are at the end of the file.  */  
79.   
80. /* Unknown, or no such operation; the enumeration constant should have 
81.    value zero.  */  
82. DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)  
83.   
84. /* --------------------------------------------------------------------- 
85.    Expressions used in constructing lists. 
86.    --------------------------------------------------------------------- */  
87.   
88. /* a linked list of expressions */  
89. DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)  
90.   
91. /* a linked list of instructions. 
92.    The insns are represented in print by their uids.  */  
93. DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", RTX_EXTRA)  
94.   
95. /* SEQUENCE appears in the result of a `gen_...' function 
96.    for a DEFINE_EXPAND that wants to make several insns. 
97.    Its elements are the bodies of the insns that should be made. 
98.    `emit_insn' takes the SEQUENCE apart and makes separate insns.  */  
99. DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)  
100.   
101. /* Refers to the address of its argument.  This is only used in alias.c.  */  
102. DEF_RTL_EXPR(ADDRESS, "address", "e", RTX_MATCH)  
103.   
104. /* ---------------------------------------------------------------------- 
105.    Expression types used for things in the instruction chain. 
106.  
107.    All formats must start with "iuu" to handle the chain. 
108.    Each insn expression holds an rtl instruction and its semantics 
109.    during back-end processing. 
110.    See macros's in "rtl.h" for the meaning of each rtx->u.fld[]. 
111.  
112.    ---------------------------------------------------------------------- */  
113.   
114. /* An instruction that cannot jump.  */  
115. DEF_RTL_EXPR(INSN, "insn", "iuuBieie", RTX_INSN)  
116.   
117. /* An instruction that can possibly jump. 
118.    Fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */  
119. DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBieie0", RTX_INSN)  
120.   
121. /* An instruction that can possibly call a subroutine 
122.    but which will not change which instruction comes next 
123.    in the current function. 
124.    Field ( rtx->u.fld[8] ) is CALL_INSN_FUNCTION_USAGE. 
125.    All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */  
126. DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuuBieiee", RTX_INSN)  
127.   
128. /* A marker that indicates that control will not flow through.  */  
129. DEF_RTL_EXPR(BARRIER, "barrier", "iuu00000", RTX_EXTRA)  
130.   
131. /* Holds a label that is followed by instructions. 
132.    Operand: 
133.    4: is used in jump.c for the use-count of the label. 
134.    5: is used in the sh backend. 
135.    6: is a number that is unique in the entire compilation. 
136.    7: is the user-given name of the label, if any.  */  
137. DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuB00is", RTX_EXTRA)  
138.   
139. /* Say where in the code a source line starts, for symbol table's sake. 
140.    Operand: 
141.    4: note-specific data 
142.    5: enum insn_note 
143.    6: unique number if insn_note == note_insn_deleted_label.  */  
144. DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)  
145.   
146. /* ---------------------------------------------------------------------- 
147.    Top level constituents of INSN, JUMP_INSN and CALL_INSN. 
148.    ---------------------------------------------------------------------- */  
149.      
150. /* Conditionally execute code. 
151.    Operand 0 is the condition that if true, the code is executed. 
152.    Operand 1 is the code to be executed (typically a SET).  
153.  
154.    Semantics are that there are no side effects if the condition 
155.    is false.  This pattern is created automatically by the if_convert 
156.    pass run after reload or by target-specific splitters.  */  
157. DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)  
158.   
159. /* Several operations to be done in parallel (perhaps under COND_EXEC).  */  
160. DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)  
161.   
162. #ifdef USE_MAPPED_LOCATION  
163. /* A string that is passed through to the assembler as input. 
164.      One can obviously pass comments through by using the 
165.      assembler comment syntax. 
166.      These occur in an insn all by themselves as the PATTERN. 
167.      They also appear inside an ASM_OPERANDS 
168.      as a convenient way to hold a string.  */  
169. DEF_RTL_EXPR(ASM_INPUT, "asm_input", "si", RTX_EXTRA)  
170.   
171. /* An assembler instruction with operands. 
172.    1st operand is the instruction template. 
173.    2nd operand is the constraint for the output. 
174.    3rd operand is the number of the output this expression refers to. 
175.      When an insn stores more than one value, a separate ASM_OPERANDS 
176.      is made for each output; this integer distinguishes them. 
177.    4th is a vector of values of input operands. 
178.    5th is a vector of modes and constraints for the input operands. 
179.      Each element is an ASM_INPUT containing a constraint string 
180.      and whose mode indicates the mode of the input operand. 
181.    6th is the source line number.  */  
182. DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEi", RTX_EXTRA)  
183. #else  
184. /* A string that is passed through to the assembler as input. 
185.      One can obviously pass comments through by using the 
186.      assembler comment syntax. 
187.      These occur in an insn all by themselves as the PATTERN. 
188.      They also appear inside an ASM_OPERANDS 
189.      as a convenient way to hold a string.  */  
190. DEF_RTL_EXPR(ASM_INPUT, "asm_input", "ssi", RTX_EXTRA)  
191.   
192. /* An assembler instruction with operands. 
193.    1st operand is the instruction template. 
194.    2nd operand is the constraint for the output. 
195.    3rd operand is the number of the output this expression refers to. 
196.      When an insn stores more than one value, a separate ASM_OPERANDS 
197.      is made for each output; this integer distinguishes them. 
198.    4th is a vector of values of input operands. 
199.    5th is a vector of modes and constraints for the input operands. 
200.      Each element is an ASM_INPUT containing a constraint string 
201.      and whose mode indicates the mode of the input operand. 
202.    6th is the name of the containing source file. 
203.    7th is the source line number.  */  
204. DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", RTX_EXTRA)  
205. #endif  
206.   
207. /* A machine-specific operation. 
208.    1st operand is a vector of operands being used by the operation so that 
209.      any needed reloads can be done. 
210.    2nd operand is a unique value saying which of a number of machine-specific 
211.      operations is to be performed. 
212.    (Note that the vector must be the first operand because of the way that 
213.    genrecog.c record positions within an insn.) 
214.  
215.    UNSPEC can occur all by itself in a PATTERN, as a component of a PARALLEL, 
216.    or inside an expression.   
217.    UNSPEC by itself or as a component of a PARALLEL 
218.    is currently considered not deletable. 
219.  
220.    FIXME: Replace all uses of UNSPEC that appears by itself or as a component 
221.    of a PARALLEL with USE. 
222.    */  
223. DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)  
224.   
225. /* Similar, but a volatile operation and one which may trap.  */  
226. DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)  
227.   
228. /* Vector of addresses, stored as full words.  */  
229. /* Each element is a LABEL_REF to a CODE_LABEL whose address we want.  */  
230. DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)  
231.   
232. /* Vector of address differences X0 - BASE, X1 - BASE, ... 
233.    First operand is BASE; the vector contains the X's. 
234.    The machine mode of this rtx says how much space to leave 
235.    for each difference and is adjusted by branch shortening if 
236.    CASE_VECTOR_SHORTEN_MODE is defined. 
237.    The third and fourth operands store the target labels with the 
238.    minimum and maximum addresses respectively. 
239.    The fifth operand stores flags for use by branch shortening. 
240.   Set at the start of shorten_branches: 
241.    min_align: the minimum alignment for any of the target labels. 
242.    base_after_vec: true iff BASE is after the ADDR_DIFF_VEC. 
243.    min_after_vec: true iff minimum addr target label is after the ADDR_DIFF_VEC. 
244.    max_after_vec: true iff maximum addr target label is after the ADDR_DIFF_VEC. 
245.    min_after_base: true iff minimum address target label is after BASE. 
246.    max_after_base: true iff maximum address target label is after BASE. 
247.   Set by the actual branch shortening process: 
248.    offset_unsigned: true iff offsets have to be treated as unsigned. 
249.    scale: scaling that is necessary to make offsets fit into the mode. 
250.  
251.    The third, fourth and fifth operands are only valid when 
252.    CASE_VECTOR_SHORTEN_MODE is defined, and only in an optimizing 
253.    compilations.  */  
254.        
255. DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eEee0", RTX_EXTRA)  
256.   
257. /* Memory prefetch, with attributes supported on some targets. 
258.    Operand 1 is the address of the memory to fetch. 
259.    Operand 2 is 1 for a write access, 0 otherwise. 
260.    Operand 3 is the level of temporal locality; 0 means there is no 
261.    temporal locality and 1, 2, and 3 are for increasing levels of temporal 
262.    locality. 
263.  
264.    The attributes specified by operands 2 and 3 are ignored for targets 
265.    whose prefetch instructions do not support them.  */  
266. DEF_RTL_EXPR(PREFETCH, "prefetch", "eee", RTX_EXTRA)  
267.   
268. /* ---------------------------------------------------------------------- 
269.    At the top level of an instruction (perhaps under PARALLEL). 
270.    ---------------------------------------------------------------------- */  
271.   
272. /* Assignment. 
273.    Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to. 
274.    Operand 2 is the value stored there. 
275.    ALL assignment must use SET. 
276.    Instructions that do multiple assignments must use multiple SET, 
277.    under PARALLEL.  */  
278. DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA)  
279.   
280. /* Indicate something is used in a way that we don't want to explain. 
281.    For example, subroutine calls will use the register 
282.    in which the static chain is passed.   
283.  
284.    USE can not appear as an operand of other rtx except for PARALLEL. 
285.    USE is not deletable, as it indicates that the operand 
286.    is used in some unknown way.  */  
287. DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)  
288.   
289. /* Indicate something is clobbered in a way that we don't want to explain. 
290.    For example, subroutine calls will clobber some physical registers 
291.    (the ones that are by convention not saved).   
292.  
293.    CLOBBER can not appear as an operand of other rtx except for PARALLEL. 
294.    CLOBBER of a hard register appearing by itself (not within PARALLEL) 
295.    is considered undeletable before reload.  */  
296. DEF_RTL_EXPR(CLOBBER, "clobber", "e", RTX_EXTRA)  
297.   
298. /* Call a subroutine. 
299.    Operand 1 is the address to call. 
300.    Operand 2 is the number of arguments.  */  
301.   
302. DEF_RTL_EXPR(CALL, "call", "ee", RTX_EXTRA)  
303.   
304. /* Return from a subroutine.  */  
305.   
306. DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA)  
307.   
308. /* Conditional trap. 
309.    Operand 1 is the condition. 
310.    Operand 2 is the trap code. 
311.    For an unconditional trap, make the condition (const_int 1).  */  
312. DEF_RTL_EXPR(TRAP_IF, "trap_if", "ee", RTX_EXTRA)  
313.   
314. /* Placeholder for _Unwind_Resume before we know if a function call 
315.    or a branch is needed.  Operand 1 is the exception region from 
316.    which control is flowing.  */  
317. DEF_RTL_EXPR(RESX, "resx", "i", RTX_EXTRA)  
318.   
319. /* ---------------------------------------------------------------------- 
320.    Primitive values for use in expressions. 
321.    ---------------------------------------------------------------------- */  
322.   
323. /* numeric integer constant */  
324. DEF_RTL_EXPR(CONST_INT, "const_int", "w", RTX_CONST_OBJ)  
325.   
326. /* fixed-point constant */  
327. DEF_RTL_EXPR(CONST_FIXED, "const_fixed", "www", RTX_CONST_OBJ)  
328.   
329. /* numeric floating point constant. 
330.    Operands hold the value.  They are all 'w' and there may be from 2 to 6; 
331.    see real.h.  */  
332. DEF_RTL_EXPR(CONST_DOUBLE, "const_double", CONST_DOUBLE_FORMAT, RTX_CONST_OBJ)  
333.   
334. /* Describes a vector constant.  */  
335. DEF_RTL_EXPR(CONST_VECTOR, "const_vector", "E", RTX_CONST_OBJ)  
336.   
337. /* String constant.  Used for attributes in machine descriptions and 
338.    for special cases in DWARF2 debug output.  NOT used for source- 
339.    language string constants.  */  
340. DEF_RTL_EXPR(CONST_STRING, "const_string", "s", RTX_OBJ)  
341.   
342. /* This is used to encapsulate an expression whose value is constant 
343.    (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be 
344.    recognized as a constant operand rather than by arithmetic instructions.  */  
345.   
346. DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ)  
347.   
348. /* program counter.  Ordinary jumps are represented 
349.    by a SET whose first operand is (PC).  */  
350. DEF_RTL_EXPR(PC, "pc", "", RTX_OBJ)  
351.   
352. /* Used in the cselib routines to describe a value.  Objects of this 
353.    kind are only allocated in cselib.c, in an alloc pool instead of 
354.    in GC memory.  The only operand of a VALUE is a cselib_val_struct.  */  
355. DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)  
356.   
357. /* A register.  The "operand" is the register number, accessed with 
358.    the REGNO macro.  If this number is less than FIRST_PSEUDO_REGISTER 
359.    than a hardware register is being referred to.  The second operand 
360.    holds the original register number - this will be different for a 
361.    pseudo register that got turned into a hard register.  The third 
362.    operand points to a reg_attrs structure. 
363.    This rtx needs to have as many (or more) fields as a MEM, since we 
364.    can change REG rtx's into MEMs during reload.  */  
365. DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)  
366.   
367. /* A scratch register.  This represents a register used only within a 
368.    single insn.  It will be turned into a REG during register allocation 
369.    or reload unless the constraint indicates that the register won't be 
370.    needed, in which case it can remain a SCRATCH.  This code is 
371.    marked as having one operand so it can be turned into a REG.  */  
372. DEF_RTL_EXPR(SCRATCH, "scratch", "0", RTX_OBJ)  
373.   
374. /* A reference to a part of another value.  The first operand is the 
375.    complete value and the second is the byte offset of the selected part.   */  
376. DEF_RTL_EXPR(SUBREG, "subreg", "ei", RTX_EXTRA)  
377.   
378. /* This one-argument rtx is used for move instructions 
379.    that are guaranteed to alter only the low part of a destination. 
380.    Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...)) 
381.    has an unspecified effect on the high part of REG, 
382.    but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...)) 
383.    is guaranteed to alter only the bits of REG that are in HImode. 
384.  
385.    The actual instruction used is probably the same in both cases, 
386.    but the register constraints may be tighter when STRICT_LOW_PART 
387.    is in use.  */  
388.   
389. DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", RTX_EXTRA)  
390.   
391. /* (CONCAT a b) represents the virtual concatenation of a and b 
392.    to make a value that has as many bits as a and b put together. 
393.    This is used for complex values.  Normally it appears only 
394.    in DECL_RTLs and during RTL generation, but not in the insn chain.  */  
395. DEF_RTL_EXPR(CONCAT, "concat", "ee", RTX_OBJ)  
396.   
397. /* (CONCATN [a1 a2 ... an]) represents the virtual concatenation of 
398.    all An to make a value.  This is an extension of CONCAT to larger 
399.    number of components.  Like CONCAT, it should not appear in the 
400.    insn chain.  Every element of the CONCATN is the same size.  */  
401. DEF_RTL_EXPR(CONCATN, "concatn", "E", RTX_OBJ)  
402.   
403. /* A memory location; operand is the address.  The second operand is the 
404.    alias set to which this MEM belongs.  We use `0' instead of `w' for this 
405.    field so that the field need not be specified in machine descriptions.  */  
406. DEF_RTL_EXPR(MEM, "mem", "e0", RTX_OBJ)  
407.   
408. /* Reference to an assembler label in the code for this function. 
409.    The operand is a CODE_LABEL found in the insn chain.  */  
410. DEF_RTL_EXPR(LABEL_REF, "label_ref", "u", RTX_CONST_OBJ)  
411.   
412. /* Reference to a named label:  
413.    Operand 0: label name 
414.    Operand 1: flags (see SYMBOL_FLAG_* in rtl.h) 
415.    Operand 2: tree from which this symbol is derived, or null. 
416.    This is either a DECL node, or some kind of constant.  */  
417. DEF_RTL_EXPR(SYMBOL_REF, "symbol_ref", "s00", RTX_CONST_OBJ)  
418.   
419. /* The condition code register is represented, in our imagination, 
420.    as a register holding a value that can be compared to zero. 
421.    In fact, the machine has already compared them and recorded the 
422.    results; but instructions that look at the condition code 
423.    pretend to be looking at the entire value and comparing it.  */  
424. DEF_RTL_EXPR(CC0, "cc0", "", RTX_OBJ)  
425.   
426. /* ---------------------------------------------------------------------- 
427.    Expressions for operators in an rtl pattern 
428.    ---------------------------------------------------------------------- */  
429.   
430. /* if_then_else.  This is used in representing ordinary 
431.    conditional jump instructions. 
432.      Operand: 
433.      0:  condition 
434.      1:  then expr 
435.      2:  else expr */  
436. DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", RTX_TERNARY)  
437.   
438. /* Comparison, produces a condition code result.  */  
439. DEF_RTL_EXPR(COMPARE, "compare", "ee", RTX_BIN_ARITH)  
440.   
441. /* plus */  
442. DEF_RTL_EXPR(PLUS, "plus", "ee", RTX_COMM_ARITH)  
443.   
444. /* Operand 0 minus operand 1.  */  
445. DEF_RTL_EXPR(MINUS, "minus", "ee", RTX_BIN_ARITH)  
446.   
447. /* Minus operand 0.  */  
448. DEF_RTL_EXPR(NEG, "neg", "e", RTX_UNARY)  
449.   
450. DEF_RTL_EXPR(MULT, "mult", "ee", RTX_COMM_ARITH)  
451.   
452. /* Multiplication with signed saturation */  
453. DEF_RTL_EXPR(SS_MULT, "ss_mult", "ee", RTX_COMM_ARITH)  
454. /* Multiplication with unsigned saturation */  
455. DEF_RTL_EXPR(US_MULT, "us_mult", "ee", RTX_COMM_ARITH)  
456.   
457. /* Operand 0 divided by operand 1.  */  
458. DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH)  
459. /* Division with signed saturation */  
460. DEF_RTL_EXPR(SS_DIV, "ss_div", "ee", RTX_BIN_ARITH)  
461. /* Division with unsigned saturation */  
462. DEF_RTL_EXPR(US_DIV, "us_div", "ee", RTX_BIN_ARITH)  
463.   
464. /* Remainder of operand 0 divided by operand 1.  */  
465. DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH)  
466.   
467. /* Unsigned divide and remainder.  */  
468. DEF_RTL_EXPR(UDIV, "udiv", "ee", RTX_BIN_ARITH)  
469. DEF_RTL_EXPR(UMOD, "umod", "ee", RTX_BIN_ARITH)  
470.   
471. /* Bitwise operations.  */  
472. DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH)  
473. DEF_RTL_EXPR(IOR, "ior", "ee", RTX_COMM_ARITH)  
474. DEF_RTL_EXPR(XOR, "xor", "ee", RTX_COMM_ARITH)  
475. DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY)  
476.   
477. /* Operand: 
478.      0:  value to be shifted. 
479.      1:  number of bits.  */  
480. DEF_RTL_EXPR(ASHIFT, "ashift", "ee", RTX_BIN_ARITH) /* shift left */  
481. DEF_RTL_EXPR(ROTATE, "rotate", "ee", RTX_BIN_ARITH) /* rotate left */  
482. DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", RTX_BIN_ARITH) /* arithmetic shift right */  
483. DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", RTX_BIN_ARITH) /* logical shift right */  
484. DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", RTX_BIN_ARITH) /* rotate right */  
485.   
486. /* Minimum and maximum values of two operands.  We need both signed and 
487.    unsigned forms.  (We cannot use MIN for SMIN because it conflicts 
488.    with a macro of the same name.)   The signed variants should be used 
489.    with floating point.  Further, if both operands are zeros, or if either 
490.    operand is NaN, then it is unspecified which of the two operands is 
491.    returned as the result.  */  
492.   
493. DEF_RTL_EXPR(SMIN, "smin", "ee", RTX_COMM_ARITH)  
494. DEF_RTL_EXPR(SMAX, "smax", "ee", RTX_COMM_ARITH)  
495. DEF_RTL_EXPR(UMIN, "umin", "ee", RTX_COMM_ARITH)  
496. DEF_RTL_EXPR(UMAX, "umax", "ee", RTX_COMM_ARITH)  
497.   
498. /* These unary operations are used to represent incrementation 
499.    and decrementation as they occur in memory addresses. 
500.    The amount of increment or decrement are not represented 
501.    because they can be understood from the machine-mode of the 
502.    containing MEM.  These operations exist in only two cases: 
503.    1. pushes onto the stack. 
504.    2. created automatically by the life_analysis pass in flow.c.  */  
505. DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", RTX_AUTOINC)  
506. DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", RTX_AUTOINC)  
507. DEF_RTL_EXPR(POST_DEC, "post_dec", "e", RTX_AUTOINC)  
508. DEF_RTL_EXPR(POST_INC, "post_inc", "e", RTX_AUTOINC)  
509.   
510. /* These binary operations are used to represent generic address 
511.    side-effects in memory addresses, except for simple incrementation 
512.    or decrementation which use the above operations.  They are 
513.    created automatically by the life_analysis pass in flow.c. 
514.    The first operand is a REG which is used as the address. 
515.    The second operand is an expression that is assigned to the 
516.    register, either before (PRE_MODIFY) or after (POST_MODIFY) 
517.    evaluating the address. 
518.    Currently, the compiler can only handle second operands of the 
519.    form (plus (reg) (reg)) and (plus (reg) (const_int)), where 
520.    the first operand of the PLUS has to be the same register as 
521.    the first operand of the *_MODIFY.  */  
522. DEF_RTL_EXPR(PRE_MODIFY, "pre_modify", "ee", RTX_AUTOINC)  
523. DEF_RTL_EXPR(POST_MODIFY, "post_modify", "ee", RTX_AUTOINC)  
524.   
525. /* Comparison operations.  The ordered comparisons exist in two 
526.    flavors, signed and unsigned.  */  
527. DEF_RTL_EXPR(NE, "ne", "ee", RTX_COMM_COMPARE)  
528. DEF_RTL_EXPR(EQ, "eq", "ee", RTX_COMM_COMPARE)  
529. DEF_RTL_EXPR(GE, "ge", "ee", RTX_COMPARE)  
530. DEF_RTL_EXPR(GT, "gt", "ee", RTX_COMPARE)  
531. DEF_RTL_EXPR(LE, "le", "ee", RTX_COMPARE)  
532. DEF_RTL_EXPR(LT, "lt", "ee", RTX_COMPARE)  
533. DEF_RTL_EXPR(GEU, "geu", "ee", RTX_COMPARE)  
534. DEF_RTL_EXPR(GTU, "gtu", "ee", RTX_COMPARE)  
535. DEF_RTL_EXPR(LEU, "leu", "ee", RTX_COMPARE)  
536. DEF_RTL_EXPR(LTU, "ltu", "ee", RTX_COMPARE)  
537.   
538. /* Additional floating point unordered comparison flavors.  */  
539. DEF_RTL_EXPR(UNORDERED, "unordered", "ee", RTX_COMM_COMPARE)  
540. DEF_RTL_EXPR(ORDERED, "ordered", "ee", RTX_COMM_COMPARE)  
541.   
542. /* These are equivalent to unordered or ...  */  
543. DEF_RTL_EXPR(UNEQ, "uneq", "ee", RTX_COMM_COMPARE)  
544. DEF_RTL_EXPR(UNGE, "unge", "ee", RTX_COMPARE)  
545. DEF_RTL_EXPR(UNGT, "ungt", "ee", RTX_COMPARE)  
546. DEF_RTL_EXPR(UNLE, "unle", "ee", RTX_COMPARE)  
547. DEF_RTL_EXPR(UNLT, "unlt", "ee", RTX_COMPARE)  
548.   
549. /* This is an ordered NE, ie !UNEQ, ie false for NaN.  */  
550. DEF_RTL_EXPR(LTGT, "ltgt", "ee", RTX_COMM_COMPARE)  
551.   
552. /* Represents the result of sign-extending the sole operand. 
553.    The machine modes of the operand and of the SIGN_EXTEND expression 
554.    determine how much sign-extension is going on.  */  
555. DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", RTX_UNARY)  
556.   
557. /* Similar for zero-extension (such as unsigned short to int).  */  
558. DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", RTX_UNARY)  
559.   
560. /* Similar but here the operand has a wider mode.  */  
561. DEF_RTL_EXPR(TRUNCATE, "truncate", "e", RTX_UNARY)  
562.   
563. /* Similar for extending floating-point values (such as SFmode to DFmode).  */  
564. DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", RTX_UNARY)  
565. DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", RTX_UNARY)  
566.   
567. /* Conversion of fixed point operand to floating point value.  */  
568. DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY)  
569.   
570. /* With fixed-point machine mode: 
571.    Conversion of floating point operand to fixed point value. 
572.    Value is defined only when the operand's value is an integer. 
573.    With floating-point machine mode (and operand with same mode): 
574.    Operand is rounded toward zero to produce an integer value 
575.    represented in floating point.  */  
576. DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)  
577.   
578. /* Conversion of unsigned fixed point operand to floating point value.  */  
579. DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)  
580.   
581. /* With fixed-point machine mode: 
582.    Conversion of floating point operand to *unsigned* fixed point value. 
583.    Value is defined only when the operand's value is an integer.  */  
584. DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", RTX_UNARY)  
585.   
586. /* Conversions involving fractional fixed-point types without saturation, 
587.    including: 
588.      fractional to fractional (of different precision), 
589.      signed integer to fractional, 
590.      fractional to signed integer, 
591.      floating point to fractional, 
592.      fractional to floating point. 
593.    NOTE: fractional can be either signed or unsigned for conversions.  */  
594. DEF_RTL_EXPR(FRACT_CONVERT, "fract_convert", "e", RTX_UNARY)  
595.   
596. /* Conversions involving fractional fixed-point types and unsigned integer 
597.    without saturation, including: 
598.      unsigned integer to fractional, 
599.      fractional to unsigned integer. 
600.    NOTE: fractional can be either signed or unsigned for conversions.  */  
601. DEF_RTL_EXPR(UNSIGNED_FRACT_CONVERT, "unsigned_fract_convert", "e", RTX_UNARY)  
602.   
603. /* Conversions involving fractional fixed-point types with saturation, 
604.    including: 
605.      fractional to fractional (of different precision), 
606.      signed integer to fractional, 
607.      floating point to fractional. 
608.    NOTE: fractional can be either signed or unsigned for conversions.  */  
609. DEF_RTL_EXPR(SAT_FRACT, "sat_fract", "e", RTX_UNARY)  
610.   
611. /* Conversions involving fractional fixed-point types and unsigned integer 
612.    with saturation, including: 
613.      unsigned integer to fractional. 
614.    NOTE: fractional can be either signed or unsigned for conversions.  */  
615. DEF_RTL_EXPR(UNSIGNED_SAT_FRACT, "unsigned_sat_fract", "e", RTX_UNARY)  
616.   
617. /* Absolute value */  
618. DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY)  
619.   
620. /* Square root */  
621. DEF_RTL_EXPR(SQRT, "sqrt", "e", RTX_UNARY)  
622.   
623. /* Swap bytes.  */  
624. DEF_RTL_EXPR(BSWAP, "bswap", "e", RTX_UNARY)  
625.   
626. /* Find first bit that is set. 
627.    Value is 1 + number of trailing zeros in the arg., 
628.    or 0 if arg is 0.  */  
629. DEF_RTL_EXPR(FFS, "ffs", "e", RTX_UNARY)  
630.   
631. /* Count leading zeros.  */  
632. DEF_RTL_EXPR(CLZ, "clz", "e", RTX_UNARY)  
633.   
634. /* Count trailing zeros.  */  
635. DEF_RTL_EXPR(CTZ, "ctz", "e", RTX_UNARY)  
636.   
637. /* Population count (number of 1 bits).  */  
638. DEF_RTL_EXPR(POPCOUNT, "popcount", "e", RTX_UNARY)  
639.   
640. /* Population parity (number of 1 bits modulo 2).  */  
641. DEF_RTL_EXPR(PARITY, "parity", "e", RTX_UNARY)  
642.   
643. /* Reference to a signed bit-field of specified size and position. 
644.    Operand 0 is the memory unit (usually SImode or QImode) which 
645.    contains the field's first bit.  Operand 1 is the width, in bits. 
646.    Operand 2 is the number of bits in the memory unit before the 
647.    first bit of this field. 
648.    If BITS_BIG_ENDIAN is defined, the first bit is the msb and 
649.    operand 2 counts from the msb of the memory unit. 
650.    Otherwise, the first bit is the lsb and operand 2 counts from 
651.    the lsb of the memory unit. 
652.    This kind of expression can not appear as an lvalue in RTL.  */  
653. DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)  
654.   
655. /* Similar for unsigned bit-field. 
656.    But note!  This kind of expression _can_ appear as an lvalue.  */  
657. DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)  
658.   
659. /* For RISC machines.  These save memory when splitting insns.  */  
660.   
661. /* HIGH are the high-order bits of a constant expression.  */  
662. DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)  
663.   
664. /* LO_SUM is the sum of a register and the low-order bits 
665.    of a constant expression.  */  
666. DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)  
667.   
668. /* Describes a merge operation between two vector values. 
669.    Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask 
670.    that specifies where the parts of the result are taken from.  Set bits 
671.    indicate operand 0, clear bits indicate operand 1.  The parts are defined 
672.    by the mode of the vectors.  */  
673. DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)  
674.   
675. /* Describes an operation that selects parts of a vector. 
676.    Operands 0 is the source vector, operand 1 is a PARALLEL that contains 
677.    a CONST_INT for each of the subparts of the result vector, giving the 
678.    number of the source subpart that should be stored into it.  */  
679. DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)  
680.   
681. /* Describes a vector concat operation.  Operands 0 and 1 are the source 
682.    vectors, the result is a vector that is as long as operands 0 and 1 
683.    combined and is the concatenation of the two source vectors.  */  
684. DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)  
685.   
686. /* Describes an operation that converts a small vector into a larger one by 
687.    duplicating the input values.  The output vector mode must have the same 
688.    submodes as the input vector mode, and the number of output parts must be 
689.    an integer multiple of the number of input parts.  */  
690. DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)  
691.        
692. /* Addition with signed saturation */  
693. DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)  
694.   
695. /* Addition with unsigned saturation */  
696. DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)  
697.   
698. /* Operand 0 minus operand 1, with signed saturation.  */  
699. DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)  
700.   
701. /* Negation with signed saturation.  */  
702. DEF_RTL_EXPR(SS_NEG, "ss_neg", "e", RTX_UNARY)  
703. /* Negation with unsigned saturation.  */  
704. DEF_RTL_EXPR(US_NEG, "us_neg", "e", RTX_UNARY)  
705.   
706. /* Absolute value with signed saturation.  */  
707. DEF_RTL_EXPR(SS_ABS, "ss_abs", "e", RTX_UNARY)  
708.   
709. /* Shift left with signed saturation.  */  
710. DEF_RTL_EXPR(SS_ASHIFT, "ss_ashift", "ee", RTX_BIN_ARITH)  
711.   
712. /* Shift left with unsigned saturation.  */  
713. DEF_RTL_EXPR(US_ASHIFT, "us_ashift", "ee", RTX_BIN_ARITH)  
714.   
715. /* Operand 0 minus operand 1, with unsigned saturation.  */  
716. DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)  
717.   
718. /* Signed saturating truncate.  */  
719. DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)  
720.   
721. /* Unsigned saturating truncate.  */  
722. DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)  
723.   
724. /* Information about the variable and its location.  */  
725. /* Changed 'te' to 'tei'; the 'i' field is for recording 
726.    initialization status of variables.  */  
727. DEF_RTL_EXPR(VAR_LOCATION, "var_location", "tei", RTX_EXTRA)  
728.   
729. /* All expressions from this point forward appear only in machine 
730.    descriptions.  */  
731. #ifdef GENERATOR_FILE  
732.   
733. /* Include a secondary machine-description file at this point.  */  
734. DEF_RTL_EXPR(INCLUDE, "include", "s", RTX_EXTRA)  
735.   
736. /* Pattern-matching operators:  */  
737.   
738. /* Use the function named by the second arg (the string) 
739.    as a predicate; if matched, store the structure that was matched 
740.    in the operand table at index specified by the first arg (the integer). 
741.    If the second arg is the null string, the structure is just stored. 
742.  
743.    A third string argument indicates to the register allocator restrictions 
744.    on where the operand can be allocated. 
745.  
746.    If the target needs no restriction on any instruction this field should 
747.    be the null string. 
748.  
749.    The string is prepended by: 
750.    '=' to indicate the operand is only written to. 
751.    '+' to indicate the operand is both read and written to. 
752.  
753.    Each character in the string represents an allocable class for an operand. 
754.    'g' indicates the operand can be any valid class. 
755.    'i' indicates the operand can be immediate (in the instruction) data. 
756.    'r' indicates the operand can be in a register. 
757.    'm' indicates the operand can be in memory. 
758.    'o' a subset of the 'm' class.  Those memory addressing modes that 
759.        can be offset at compile time (have a constant added to them). 
760.  
761.    Other characters indicate target dependent operand classes and 
762.    are described in each target's machine description. 
763.  
764.    For instructions with more than one operand, sets of classes can be 
765.    separated by a comma to indicate the appropriate multi-operand constraints. 
766.    There must be a 1 to 1 correspondence between these sets of classes in 
767.    all operands for an instruction. 
768.    */  
769. DEF_RTL_EXPR(MATCH_OPERAND, "match_operand", "iss", RTX_MATCH)  
770.   
771. /* Match a SCRATCH or a register.  When used to generate rtl, a 
772.    SCRATCH is generated.  As for MATCH_OPERAND, the mode specifies 
773.    the desired mode and the first argument is the operand number. 
774.    The second argument is the constraint.  */  
775. DEF_RTL_EXPR(MATCH_SCRATCH, "match_scratch", "is", RTX_MATCH)  
776.   
777. /* Apply a predicate, AND match recursively the operands of the rtx. 
778.    Operand 0 is the operand-number, as in match_operand. 
779.    Operand 1 is a predicate to apply (as a string, a function name). 
780.    Operand 2 is a vector of expressions, each of which must match 
781.    one subexpression of the rtx this construct is matching.  */  
782. DEF_RTL_EXPR(MATCH_OPERATOR, "match_operator", "isE", RTX_MATCH)  
783.   
784. /* Match a PARALLEL of arbitrary length.  The predicate is applied 
785.    to the PARALLEL and the initial expressions in the PARALLEL are matched. 
786.    Operand 0 is the operand-number, as in match_operand. 
787.    Operand 1 is a predicate to apply to the PARALLEL. 
788.    Operand 2 is a vector of expressions, each of which must match the  
789.    corresponding element in the PARALLEL.  */  
790. DEF_RTL_EXPR(MATCH_PARALLEL, "match_parallel", "isE", RTX_MATCH)  
791.   
792. /* Match only something equal to what is stored in the operand table 
793.    at the index specified by the argument.  Use with MATCH_OPERAND.  */  
794. DEF_RTL_EXPR(MATCH_DUP, "match_dup", "i", RTX_MATCH)  
795.   
796. /* Match only something equal to what is stored in the operand table 
797.    at the index specified by the argument.  Use with MATCH_OPERATOR.  */  
798. DEF_RTL_EXPR(MATCH_OP_DUP, "match_op_dup", "iE", RTX_MATCH)  
799.   
800. /* Match only something equal to what is stored in the operand table 
801.    at the index specified by the argument.  Use with MATCH_PARALLEL.  */  
802. DEF_RTL_EXPR(MATCH_PAR_DUP, "match_par_dup", "iE", RTX_MATCH)  
803.   
804. /* Appears only in define_predicate/define_special_predicate 
805.    expressions.  Evaluates true only if the operand has an RTX code 
806.    from the set given by the argument (a comma-separated list).  If the 
807.    second argument is present and nonempty, it is a sequence of digits 
808.    and/or letters which indicates the subexpression to test, using the 
809.    same syntax as genextract/genrecog's location strings: 0-9 for 
810.    XEXP (op, n), a-z for XVECEXP (op, 0, n); each character applies to 
811.    the result of the one before it.  */  
812. DEF_RTL_EXPR(MATCH_CODE, "match_code", "ss", RTX_MATCH)  
813.   
814. /* Appears only in define_predicate/define_special_predicate 
815.     expressions.  The argument is a C expression to be injected at this 
816.     point in the predicate formula.  */  
817. DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)  
818.   
819. /* Insn (and related) definitions.  */  
820.   
821. /* Definition of the pattern for one kind of instruction. 
822.    Operand: 
823.    0: names this instruction. 
824.       If the name is the null string, the instruction is in the 
825.       machine description just to be recognized, and will never be emitted by 
826.       the tree to rtl expander. 
827.    1: is the pattern. 
828.    2: is a string which is a C expression 
829.       giving an additional condition for recognizing this pattern. 
830.       A null string means no extra condition. 
831.    3: is the action to execute if this pattern is matched. 
832.       If this assembler code template starts with a * then it is a fragment of 
833.       C code to run to decide on a template to use.  Otherwise, it is the 
834.       template to use. 
835.    4: optionally, a vector of attributes for this insn. 
836.      */  
837. DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)  
838.   
839. /* Definition of a peephole optimization. 
840.    1st operand: vector of insn patterns to match 
841.    2nd operand: C expression that must be true 
842.    3rd operand: template or C code to produce assembler output. 
843.    4: optionally, a vector of attributes for this insn. 
844.  
845.    This form is deprecated; use define_peephole2 instead.  */  
846. DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)  
847.   
848. /* Definition of a split operation. 
849.    1st operand: insn pattern to match 
850.    2nd operand: C expression that must be true 
851.    3rd operand: vector of insn patterns to place into a SEQUENCE 
852.    4th operand: optionally, some C code to execute before generating the 
853.  insns.  This might, for example, create some RTX's and store them in 
854.  elements of `recog_data.operand' for use by the vector of 
855.  insn-patterns. 
856.  (`operands' is an alias here for `recog_data.operand').  */  
857. DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)  
858.   
859. /* Definition of an insn and associated split. 
860.    This is the concatenation, with a few modifications, of a define_insn 
861.    and a define_split which share the same pattern. 
862.    Operand: 
863.    0: names this instruction. 
864.       If the name is the null string, the instruction is in the 
865.       machine description just to be recognized, and will never be emitted by 
866.       the tree to rtl expander. 
867.    1: is the pattern. 
868.    2: is a string which is a C expression 
869.       giving an additional condition for recognizing this pattern. 
870.       A null string means no extra condition. 
871.    3: is the action to execute if this pattern is matched. 
872.       If this assembler code template starts with a * then it is a fragment of 
873.       C code to run to decide on a template to use.  Otherwise, it is the 
874.       template to use. 
875.    4: C expression that must be true for split.  This may start with "&&" 
876.       in which case the split condition is the logical and of the insn  
877.       condition and what follows the "&&" of this operand. 
878.    5: vector of insn patterns to place into a SEQUENCE 
879.    6: optionally, some C code to execute before generating the 
880.  insns.  This might, for example, create some RTX's and store them in 
881.  elements of `recog_data.operand' for use by the vector of 
882.  insn-patterns. 
883.  (`operands' is an alias here for `recog_data.operand').   
884.    7: optionally, a vector of attributes for this insn.  */  
885. DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)  
886.   
887. /* Definition of an RTL peephole operation. 
888.    Follows the same arguments as define_split.  */  
889. DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)  
890.   
891. /* Define how to generate multiple insns for a standard insn name. 
892.    1st operand: the insn name. 
893.    2nd operand: vector of insn-patterns. 
894.  Use match_operand to substitute an element of `recog_data.operand'. 
895.    3rd operand: C expression that must be true for this to be available. 
896.  This may not test any operands. 
897.    4th operand: Extra C code to execute before generating the insns. 
898.  This might, for example, create some RTX's and store them in 
899.  elements of `recog_data.operand' for use by the vector of 
900.  insn-patterns. 
901.  (`operands' is an alias here for `recog_data.operand').  */  
902. DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEss", RTX_EXTRA)  
903.      
904. /* Define a requirement for delay slots. 
905.    1st operand: Condition involving insn attributes that, if true, 
906.          indicates that the insn requires the number of delay slots 
907.   shown. 
908.    2nd operand: Vector whose length is the three times the number of delay 
909.   slots required. 
910.          Each entry gives three conditions, each involving attributes. 
911.   The first must be true for an insn to occupy that delay slot 
912.   location.  The second is true for all insns that can be 
913.   annulled if the branch is true and the third is true for all 
914.   insns that can be annulled if the branch is false.  
915.  
916.    Multiple DEFINE_DELAYs may be present.  They indicate differing 
917.    requirements for delay slots.  */  
918. DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", RTX_EXTRA)  
919.   
920. /* Define attribute computation for `asm' instructions.  */  
921. DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)  
922.   
923. /* Definition of a conditional execution meta operation.  Automatically 
924.    generates new instances of DEFINE_INSN, selected by having attribute 
925.    "predicable" true.  The new pattern will contain a COND_EXEC and the 
926.    predicate at top-level. 
927.  
928.    Operand: 
929.    0: The predicate pattern.  The top-level form should match a 
930.       relational operator.  Operands should have only one alternative. 
931.    1: A C expression giving an additional condition for recognizing 
932.       the generated pattern. 
933.    2: A template or C code to produce assembler output.  */  
934. DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "Ess", RTX_EXTRA)  
935.   
936. /* Definition of an operand predicate.  The difference between 
937.    DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will 
938.    not warn about a match_operand with no mode if it has a predicate 
939.    defined with DEFINE_SPECIAL_PREDICATE. 
940.  
941.    Operand: 
942.    0: The name of the predicate. 
943.    1: A boolean expression which computes whether or not the predicate 
944.       matches.  This expression can use IOR, AND, NOT, MATCH_OPERAND, 
945.       MATCH_CODE, and MATCH_TEST.  It must be specific enough that genrecog 
946.       can calculate the set of RTX codes that can possibly match. 
947.    2: A C function body which must return true for the predicate to match. 
948.       Optional.  Use this when the test is too complicated to fit into a 
949.       match_test expression.  */  
950. DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)  
951. DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)  
952.   
953. /* Definition of a register operand constraint.  This simply maps the 
954.    constraint string to a register class. 
955.  
956.    Operand: 
957.    0: The name of the constraint (often, but not always, a single letter). 
958.    1: A C expression which evaluates to the appropriate register class for 
959.       this constraint.  If this is not just a constant, it should look only 
960.       at -m switches and the like. 
961.    2: A docstring for this constraint, in Texinfo syntax; not currently 
962.       used, in future will be incorporated into the manual's list of 
963.       machine-specific operand constraints.  */  
964. DEF_RTL_EXPR(DEFINE_REGISTER_CONSTRAINT, "define_register_constraint", "sss", RTX_EXTRA)  
965.   
966. /* Definition of a non-register operand constraint.  These look at the 
967.    operand and decide whether it fits the constraint. 
968.  
969.    DEFINE_CONSTRAINT gets no special treatment if it fails to match. 
970.    It is appropriate for constant-only constraints, and most others. 
971.  
972.    DEFINE_MEMORY_CONSTRAINT tells reload that this constraint can be made 
973.    to match, if it doesn't already, by converting the operand to the form 
974.    (mem (reg X)) where X is a base register.  It is suitable for constraints 
975.    that describe a subset of all memory references. 
976.  
977.    DEFINE_ADDRESS_CONSTRAINT tells reload that this constraint can be made 
978.    to match, if it doesn't already, by converting the operand to the form 
979.    (reg X) where X is a base register.  It is suitable for constraints that 
980.    describe a subset of all address references. 
981.  
982.    When in doubt, use plain DEFINE_CONSTRAINT.   
983.  
984.    Operand: 
985.    0: The name of the constraint (often, but not always, a single letter). 
986.    1: A docstring for this constraint, in Texinfo syntax; not currently 
987.       used, in future will be incorporated into the manual's list of 
988.       machine-specific operand constraints. 
989.    2: A boolean expression which computes whether or not the constraint 
990.       matches.  It should follow the same rules as a define_predicate 
991.       expression, including the bit about specifying the set of RTX codes 
992.       that could possibly match.  MATCH_TEST subexpressions may make use of 
993.       these variables: 
994.         `op'    - the RTL object defining the operand. 
995.         `mode'  - the mode of `op'. 
996.  `ival'  - INTVAL(op), if op is a CONST_INT. 
997.         `hval'  - CONST_DOUBLE_HIGH(op), if op is an integer CONST_DOUBLE. 
998.         `lval'  - CONST_DOUBLE_LOW(op), if op is an integer CONST_DOUBLE. 
999.         `rval'  - CONST_DOUBLE_REAL_VALUE(op), if op is a floating-point 
1000.                   CONST_DOUBLE. 
1001.       Do not use ival/hval/lval/rval if op is not the appropriate kind of 
1002.       RTL object.  */  
1003. DEF_RTL_EXPR(DEFINE_CONSTRAINT, "define_constraint", "sse", RTX_EXTRA)  
1004. DEF_RTL_EXPR(DEFINE_MEMORY_CONSTRAINT, "define_memory_constraint", "sse", RTX_EXTRA)  
1005. DEF_RTL_EXPR(DEFINE_ADDRESS_CONSTRAINT, "define_address_constraint", "sse", RTX_EXTRA)  
1006.      
1007.   
1008. /* Constructions for CPU pipeline description described by NDFAs.  */  
1009.   
1010. /* (define_cpu_unit string [string]) describes cpu functional 
1011.    units (separated by comma). 
1012.  
1013.    1st operand: Names of cpu functional units. 
1014.    2nd operand: Name of automaton (see comments for DEFINE_AUTOMATON). 
1015.  
1016.    All define_reservations, define_cpu_units, and 
1017.    define_query_cpu_units should have unique names which may not be 
1018.    "nothing".  */  
1019. DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", RTX_EXTRA)  
1020.   
1021. /* (define_query_cpu_unit string [string]) describes cpu functional 
1022.    units analogously to define_cpu_unit.  The reservation of such 
1023.    units can be queried for automaton state.  */  
1024. DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", RTX_EXTRA)  
1025.   
1026. /* (exclusion_set string string) means that each CPU functional unit 
1027.    in the first string can not be reserved simultaneously with any 
1028.    unit whose name is in the second string and vise versa.  CPU units 
1029.    in the string are separated by commas.  For example, it is useful 
1030.    for description CPU with fully pipelined floating point functional 
1031.    unit which can execute simultaneously only single floating point 
1032.    insns or only double floating point insns.  All CPU functional 
1033.    units in a set should belong to the same automaton.  */  
1034. DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", RTX_EXTRA)  
1035.   
1036. /* (presence_set string string) means that each CPU functional unit in 
1037.    the first string can not be reserved unless at least one of pattern 
1038.    of units whose names are in the second string is reserved.  This is 
1039.    an asymmetric relation.  CPU units or unit patterns in the strings 
1040.    are separated by commas.  Pattern is one unit name or unit names 
1041.    separated by white-spaces. 
1042.   
1043.    For example, it is useful for description that slot1 is reserved 
1044.    after slot0 reservation for a VLIW processor.  We could describe it 
1045.    by the following construction 
1046.  
1047.       (presence_set "slot1" "slot0") 
1048.  
1049.    Or slot1 is reserved only after slot0 and unit b0 reservation.  In 
1050.    this case we could write 
1051.  
1052.       (presence_set "slot1" "slot0 b0") 
1053.  
1054.    All CPU functional units in a set should belong to the same 
1055.    automaton.  */  
1056. DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", RTX_EXTRA)  
1057.   
1058. /* (final_presence_set string string) is analogous to `presence_set'. 
1059.    The difference between them is when checking is done.  When an 
1060.    instruction is issued in given automaton state reflecting all 
1061.    current and planned unit reservations, the automaton state is 
1062.    changed.  The first state is a source state, the second one is a 
1063.    result state.  Checking for `presence_set' is done on the source 
1064.    state reservation, checking for `final_presence_set' is done on the 
1065.    result reservation.  This construction is useful to describe a 
1066.    reservation which is actually two subsequent reservations.  For 
1067.    example, if we use  
1068.  
1069.       (presence_set "slot1" "slot0") 
1070.  
1071.    the following insn will be never issued (because slot1 requires 
1072.    slot0 which is absent in the source state). 
1073.  
1074.       (define_reservation "insn_and_nop" "slot0 + slot1") 
1075.  
1076.    but it can be issued if we use analogous `final_presence_set'.  */  
1077. DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", RTX_EXTRA)  
1078.   
1079. /* (absence_set string string) means that each CPU functional unit in 
1080.    the first string can be reserved only if each pattern of units 
1081.    whose names are in the second string is not reserved.  This is an 
1082.    asymmetric relation (actually exclusion set is analogous to this 
1083.    one but it is symmetric).  CPU units or unit patterns in the string 
1084.    are separated by commas.  Pattern is one unit name or unit names 
1085.    separated by white-spaces. 
1086.  
1087.    For example, it is useful for description that slot0 can not be 
1088.    reserved after slot1 or slot2 reservation for a VLIW processor.  We 
1089.    could describe it by the following construction 
1090.  
1091.       (absence_set "slot2" "slot0, slot1") 
1092.  
1093.    Or slot2 can not be reserved if slot0 and unit b0 are reserved or 
1094.    slot1 and unit b1 are reserved .  In this case we could write 
1095.  
1096.       (absence_set "slot2" "slot0 b0, slot1 b1") 
1097.  
1098.    All CPU functional units in a set should to belong the same 
1099.    automaton.  */  
1100. DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", RTX_EXTRA)  
1101.   
1102. /* (final_absence_set string string) is analogous to `absence_set' but 
1103.    checking is done on the result (state) reservation.  See comments 
1104.    for `final_presence_set'.  */  
1105. DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", RTX_EXTRA)  
1106.   
1107. /* (define_bypass number out_insn_names in_insn_names) names bypass 
1108.    with given latency (the first number) from insns given by the first 
1109.    string (see define_insn_reservation) into insns given by the second 
1110.    string.  Insn names in the strings are separated by commas.  The 
1111.    third operand is optional name of function which is additional 
1112.    guard for the bypass.  The function will get the two insns as 
1113.    parameters.  If the function returns zero the bypass will be 
1114.    ignored for this case.  Additional guard is necessary to recognize 
1115.    complicated bypasses, e.g. when consumer is load address.  */  
1116. DEF_RTL_EXPR(DEFINE_BYPASS, "define_bypass", "issS", RTX_EXTRA)  
1117.   
1118. /* (define_automaton string) describes names of automata generated and 
1119.    used for pipeline hazards recognition.  The names are separated by 
1120.    comma.  Actually it is possibly to generate the single automaton 
1121.    but unfortunately it can be very large.  If we use more one 
1122.    automata, the summary size of the automata usually is less than the 
1123.    single one.  The automaton name is used in define_cpu_unit and 
1124.    define_query_cpu_unit.  All automata should have unique names.  */  
1125. DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", RTX_EXTRA)  
1126.   
1127. /* (automata_option string) describes option for generation of 
1128.    automata.  Currently there are the following options: 
1129.  
1130.    o "no-minimization" which makes no minimization of automata.  This 
1131.      is only worth to do when we are debugging the description and 
1132.      need to look more accurately at reservations of states. 
1133.  
1134.    o "time" which means printing additional time statistics about 
1135.       generation of automata. 
1136.    
1137.    o "v" which means generation of file describing the result 
1138.      automata.  The file has suffix `.dfa' and can be used for the 
1139.      description verification and debugging. 
1140.  
1141.    o "w" which means generation of warning instead of error for 
1142.      non-critical errors. 
1143.  
1144.    o "ndfa" which makes nondeterministic finite state automata. 
1145.  
1146.    o "progress" which means output of a progress bar showing how many 
1147.      states were generated so far for automaton being processed.  */  
1148. DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)  
1149.   
1150. /* (define_reservation string string) names reservation (the first 
1151.    string) of cpu functional units (the 2nd string).  Sometimes unit 
1152.    reservations for different insns contain common parts.  In such 
1153.    case, you can describe common part and use its name (the 1st 
1154.    parameter) in regular expression in define_insn_reservation.  All 
1155.    define_reservations, define_cpu_units, and define_query_cpu_units 
1156.    should have unique names which may not be "nothing".  */  
1157. DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)  
1158.   
1159. /* (define_insn_reservation name default_latency condition regexpr) 
1160.    describes reservation of cpu functional units (the 3nd operand) for 
1161.    instruction which is selected by the condition (the 2nd parameter). 
1162.    The first parameter is used for output of debugging information. 
1163.    The reservations are described by a regular expression according 
1164.    the following syntax: 
1165.  
1166.        regexp = regexp "," oneof 
1167.               | oneof 
1168.  
1169.        oneof = oneof "|" allof 
1170.              | allof 
1171.  
1172.        allof = allof "+" repeat 
1173.              | repeat 
1174.   
1175.        repeat = element "*" number 
1176.               | element 
1177.  
1178.        element = cpu_function_unit_name 
1179.                | reservation_name 
1180.                | result_name 
1181.                | "nothing" 
1182.                | "(" regexp ")" 
1183.  
1184.        1. "," is used for describing start of the next cycle in 
1185.        reservation. 
1186.  
1187.        2. "|" is used for describing the reservation described by the 
1188.        first regular expression *or* the reservation described by the 
1189.        second regular expression *or* etc. 
1190.  
1191.        3. "+" is used for describing the reservation described by the 
1192.        first regular expression *and* the reservation described by the 
1193.        second regular expression *and* etc. 
1194.  
1195.        4. "*" is used for convenience and simply means sequence in 
1196.        which the regular expression are repeated NUMBER times with 
1197.        cycle advancing (see ","). 
1198.  
1199.        5. cpu functional unit name which means its reservation. 
1200.  
1201.        6. reservation name -- see define_reservation. 
1202.  
1203.        7. string "nothing" means no units reservation.  */  
1204.   
1205. DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)  
1206.   
1207. /* Expressions used for insn attributes.  */  
1208.   
1209. /* Definition of an insn attribute. 
1210.    1st operand: name of the attribute 
1211.    2nd operand: comma-separated list of possible attribute values 
1212.    3rd operand: expression for the default value of the attribute.  */  
1213. DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)  
1214.   
1215. /* Marker for the name of an attribute.  */  
1216. DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)  
1217.   
1218. /* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and 
1219.    in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that 
1220.    pattern. 
1221.  
1222.    (set_attr "name" "value") is equivalent to 
1223.    (set (attr "name") (const_string "value"))  */  
1224. DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)  
1225.   
1226. /* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to 
1227.    specify that attribute values are to be assigned according to the 
1228.    alternative matched. 
1229.  
1230.    The following three expressions are equivalent: 
1231.  
1232.    (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1") 
1233.        (eq_attrq "alternative" "2") (const_string "a2")] 
1234.       (const_string "a3"))) 
1235.    (set_attr_alternative "att" [(const_string "a1") (const_string "a2") 
1236.      (const_string "a3")]) 
1237.    (set_attr "att" "a1,a2,a3") 
1238.  */  
1239. DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)  
1240.   
1241. /* A conditional expression true if the value of the specified attribute of 
1242.    the current insn equals the specified value.  The first operand is the 
1243.    attribute name and the second is the comparison value.  */  
1244. DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)  
1245.   
1246. /* A special case of the above representing a set of alternatives.  The first 
1247.    operand is bitmap of the set, the second one is the default value.  */  
1248. DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)  
1249.   
1250. /* A conditional expression which is true if the specified flag is 
1251.    true for the insn being scheduled in reorg. 
1252.  
1253.    genattr.c defines the following flags which can be tested by 
1254.    (attr_flag "foo") expressions in eligible_for_delay. 
1255.  
1256.    forward, backward, very_likely, likely, very_unlikely, and unlikely.  */  
1257.   
1258. DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)  
1259.   
1260. /* General conditional. The first operand is a vector composed of pairs of 
1261.    expressions.  The first element of each pair is evaluated, in turn. 
1262.    The value of the conditional is the second expression of the first pair 
1263.    whose first expression evaluates nonzero.  If none of the expressions is 
1264.    true, the second operand will be used as the value of the conditional.  */  
1265. DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)  
1266.   
1267. #endif /* GENERATOR_FILE */  
1268.   
1269. /* 
1270. Local variables: 
1271. mode:c 
1272. End: 
1273. */  
1274. </http:>  

/* This file contains the definitions and documentation for the
   Register Transfer Expressions (rtx's) that make up the
   Register Transfer Language (rtl) used in the Back End of the GNU compiler.
   Copyright (C) 1987, 1988, 1992, 1994, 1995, 1997, 1998, 1999, 2000, 2004,
   2005, 2006, 2007
   Free Software Foundation, Inc.

This file is part of GCC.

GCC 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 3, or (at your option) any later
version.

GCC 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 GCC; see the file COPYING3.  If not see
.  */


/* Expression definitions and descriptions for all targets are in this file.
   Some will not be used for some targets.

   The fields in the cpp macro call "DEF_RTL_EXPR()"
   are used to create declarations in the C source of the compiler.

   The fields are:

   1.  The internal name of the rtx used in the C source.
   It is a tag in the enumeration "enum rtx_code" defined in "rtl.h".
   By convention these are in UPPER_CASE.

   2.  The name of the rtx in the external ASCII format read by
   read_rtx(), and printed by print_rtx().
   These names are stored in rtx_name[].
   By convention these are the internal (field 1) names in lower_case.

   3.  The print format, and type of each rtx->u.fld[] (field) in this rtx.
   These formats are stored in rtx_format[].
   The meaning of the formats is documented in front of this array in rtl.c
   
   4.  The class of the rtx.  These are stored in rtx_class and are accessed
   via the GET_RTX_CLASS macro.  They are defined as follows:

     RTX_CONST_OBJ
         an rtx code that can be used to represent a constant object
         (e.g, CONST_INT)
     RTX_OBJ
         an rtx code that can be used to represent an object (e.g, REG, MEM)
     RTX_COMPARE
         an rtx code for a comparison (e.g, LT, GT)
     RTX_COMM_COMPARE
         an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED)
     RTX_UNARY
         an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
     RTX_COMM_ARITH
         an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
     RTX_TERNARY
         an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
     RTX_BIN_ARITH
         an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
     RTX_BITFIELD_OPS
         an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
     RTX_INSN
         an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN)
     RTX_MATCH
         an rtx code for something that matches in insns (e.g, MATCH_DUP)
     RTX_AUTOINC
         an rtx code for autoincrement addressing modes (e.g. POST_DEC)
     RTX_EXTRA
         everything else

   All of the expressions that appear only in machine descriptions,
   not in RTL used by the compiler itself, are at the end of the file.  */

/* Unknown, or no such operation; the enumeration constant should have
   value zero.  */
DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)

/* ---------------------------------------------------------------------
   Expressions used in constructing lists.
   --------------------------------------------------------------------- */

/* a linked list of expressions */
DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)

/* a linked list of instructions.
   The insns are represented in print by their uids.  */
DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", RTX_EXTRA)

/* SEQUENCE appears in the result of a `gen_...' function
   for a DEFINE_EXPAND that wants to make several insns.
   Its elements are the bodies of the insns that should be made.
   `emit_insn' takes the SEQUENCE apart and makes separate insns.  */
DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)

/* Refers to the address of its argument.  This is only used in alias.c.  */
DEF_RTL_EXPR(ADDRESS, "address", "e", RTX_MATCH)

/* ----------------------------------------------------------------------
   Expression types used for things in the instruction chain.

   All formats must start with "iuu" to handle the chain.
   Each insn expression holds an rtl instruction and its semantics
   during back-end processing.
   See macros's in "rtl.h" for the meaning of each rtx->u.fld[].

   ---------------------------------------------------------------------- */

/* An instruction that cannot jump.  */
DEF_RTL_EXPR(INSN, "insn", "iuuBieie", RTX_INSN)

/* An instruction that can possibly jump.
   Fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBieie0", RTX_INSN)

/* An instruction that can possibly call a subroutine
   but which will not change which instruction comes next
   in the current function.
   Field ( rtx->u.fld[8] ) is CALL_INSN_FUNCTION_USAGE.
   All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuuBieiee", RTX_INSN)

/* A marker that indicates that control will not flow through.  */
DEF_RTL_EXPR(BARRIER, "barrier", "iuu00000", RTX_EXTRA)

/* Holds a label that is followed by instructions.
   Operand:
   4: is used in jump.c for the use-count of the label.
   5: is used in the sh backend.
   6: is a number that is unique in the entire compilation.
   7: is the user-given name of the label, if any.  */
DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuB00is", RTX_EXTRA)

/* Say where in the code a source line starts, for symbol table's sake.
   Operand:
   4: note-specific data
   5: enum insn_note
   6: unique number if insn_note == note_insn_deleted_label.  */
DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)

/* ----------------------------------------------------------------------
   Top level constituents of INSN, JUMP_INSN and CALL_INSN.
   ---------------------------------------------------------------------- */
   
/* Conditionally execute code.
   Operand 0 is the condition that if true, the code is executed.
   Operand 1 is the code to be executed (typically a SET). 

   Semantics are that there are no side effects if the condition
   is false.  This pattern is created automatically by the if_convert
   pass run after reload or by target-specific splitters.  */
DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)

/* Several operations to be done in parallel (perhaps under COND_EXEC).  */
DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)

#ifdef USE_MAPPED_LOCATION
/* A string that is passed through to the assembler as input.
     One can obviously pass comments through by using the
     assembler comment syntax.
     These occur in an insn all by themselves as the PATTERN.
     They also appear inside an ASM_OPERANDS
     as a convenient way to hold a string.  */
DEF_RTL_EXPR(ASM_INPUT, "asm_input", "si", RTX_EXTRA)

/* An assembler instruction with operands.
   1st operand is the instruction template.
   2nd operand is the constraint for the output.
   3rd operand is the number of the output this expression refers to.
     When an insn stores more than one value, a separate ASM_OPERANDS
     is made for each output; this integer distinguishes them.
   4th is a vector of values of input operands.
   5th is a vector of modes and constraints for the input operands.
     Each element is an ASM_INPUT containing a constraint string
     and whose mode indicates the mode of the input operand.
   6th is the source line number.  */
DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEi", RTX_EXTRA)
#else
/* A string that is passed through to the assembler as input.
     One can obviously pass comments through by using the
     assembler comment syntax.
     These occur in an insn all by themselves as the PATTERN.
     They also appear inside an ASM_OPERANDS
     as a convenient way to hold a string.  */
DEF_RTL_EXPR(ASM_INPUT, "asm_input", "ssi", RTX_EXTRA)

/* An assembler instruction with operands.
   1st operand is the instruction template.
   2nd operand is the constraint for the output.
   3rd operand is the number of the output this expression refers to.
     When an insn stores more than one value, a separate ASM_OPERANDS
     is made for each output; this integer distinguishes them.
   4th is a vector of values of input operands.
   5th is a vector of modes and constraints for the input operands.
     Each element is an ASM_INPUT containing a constraint string
     and whose mode indicates the mode of the input operand.
   6th is the name of the containing source file.
   7th is the source line number.  */
DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", RTX_EXTRA)
#endif

/* A machine-specific operation.
   1st operand is a vector of operands being used by the operation so that
     any needed reloads can be done.
   2nd operand is a unique value saying which of a number of machine-specific
     operations is to be performed.
   (Note that the vector must be the first operand because of the way that
   genrecog.c record positions within an insn.)

   UNSPEC can occur all by itself in a PATTERN, as a component of a PARALLEL,
   or inside an expression.  
   UNSPEC by itself or as a component of a PARALLEL
   is currently considered not deletable.

   FIXME: Replace all uses of UNSPEC that appears by itself or as a component
   of a PARALLEL with USE.
   */
DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)

/* Similar, but a volatile operation and one which may trap.  */
DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)

/* Vector of addresses, stored as full words.  */
/* Each element is a LABEL_REF to a CODE_LABEL whose address we want.  */
DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)

/* Vector of address differences X0 - BASE, X1 - BASE, ...
   First operand is BASE; the vector contains the X's.
   The machine mode of this rtx says how much space to leave
   for each difference and is adjusted by branch shortening if
   CASE_VECTOR_SHORTEN_MODE is defined.
   The third and fourth operands store the target labels with the
   minimum and maximum addresses respectively.
   The fifth operand stores flags for use by branch shortening.
  Set at the start of shorten_branches:
   min_align: the minimum alignment for any of the target labels.
   base_after_vec: true iff BASE is after the ADDR_DIFF_VEC.
   min_after_vec: true iff minimum addr target label is after the ADDR_DIFF_VEC.
   max_after_vec: true iff maximum addr target label is after the ADDR_DIFF_VEC.
   min_after_base: true iff minimum address target label is after BASE.
   max_after_base: true iff maximum address target label is after BASE.
  Set by the actual branch shortening process:
   offset_unsigned: true iff offsets have to be treated as unsigned.
   scale: scaling that is necessary to make offsets fit into the mode.

   The third, fourth and fifth operands are only valid when
   CASE_VECTOR_SHORTEN_MODE is defined, and only in an optimizing
   compilations.  */
     
DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eEee0", RTX_EXTRA)

/* Memory prefetch, with attributes supported on some targets.
   Operand 1 is the address of the memory to fetch.
   Operand 2 is 1 for a write access, 0 otherwise.
   Operand 3 is the level of temporal locality; 0 means there is no
   temporal locality and 1, 2, and 3 are for increasing levels of temporal
   locality.

   The attributes specified by operands 2 and 3 are ignored for targets
   whose prefetch instructions do not support them.  */
DEF_RTL_EXPR(PREFETCH, "prefetch", "eee", RTX_EXTRA)

/* ----------------------------------------------------------------------
   At the top level of an instruction (perhaps under PARALLEL).
   ---------------------------------------------------------------------- */

/* Assignment.
   Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to.
   Operand 2 is the value stored there.
   ALL assignment must use SET.
   Instructions that do multiple assignments must use multiple SET,
   under PARALLEL.  */
DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA)

/* Indicate something is used in a way that we don't want to explain.
   For example, subroutine calls will use the register
   in which the static chain is passed.  

   USE can not appear as an operand of other rtx except for PARALLEL.
   USE is not deletable, as it indicates that the operand
   is used in some unknown way.  */
DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)

/* Indicate something is clobbered in a way that we don't want to explain.
   For example, subroutine calls will clobber some physical registers
   (the ones that are by convention not saved).  

   CLOBBER can not appear as an operand of other rtx except for PARALLEL.
   CLOBBER of a hard register appearing by itself (not within PARALLEL)
   is considered undeletable before reload.  */
DEF_RTL_EXPR(CLOBBER, "clobber", "e", RTX_EXTRA)

/* Call a subroutine.
   Operand 1 is the address to call.
   Operand 2 is the number of arguments.  */

DEF_RTL_EXPR(CALL, "call", "ee", RTX_EXTRA)

/* Return from a subroutine.  */

DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA)

/* Conditional trap.
   Operand 1 is the condition.
   Operand 2 is the trap code.
   For an unconditional trap, make the condition (const_int 1).  */
DEF_RTL_EXPR(TRAP_IF, "trap_if", "ee", RTX_EXTRA)

/* Placeholder for _Unwind_Resume before we know if a function call
   or a branch is needed.  Operand 1 is the exception region from
   which control is flowing.  */
DEF_RTL_EXPR(RESX, "resx", "i", RTX_EXTRA)

/* ----------------------------------------------------------------------
   Primitive values for use in expressions.
   ---------------------------------------------------------------------- */

/* numeric integer constant */
DEF_RTL_EXPR(CONST_INT, "const_int", "w", RTX_CONST_OBJ)

/* fixed-point constant */
DEF_RTL_EXPR(CONST_FIXED, "const_fixed", "www", RTX_CONST_OBJ)

/* numeric floating point constant.
   Operands hold the value.  They are all 'w' and there may be from 2 to 6;
   see real.h.  */
DEF_RTL_EXPR(CONST_DOUBLE, "const_double", CONST_DOUBLE_FORMAT, RTX_CONST_OBJ)

/* Describes a vector constant.  */
DEF_RTL_EXPR(CONST_VECTOR, "const_vector", "E", RTX_CONST_OBJ)

/* String constant.  Used for attributes in machine descriptions and
   for special cases in DWARF2 debug output.  NOT used for source-
   language string constants.  */
DEF_RTL_EXPR(CONST_STRING, "const_string", "s", RTX_OBJ)

/* This is used to encapsulate an expression whose value is constant
   (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be
   recognized as a constant operand rather than by arithmetic instructions.  */

DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ)

/* program counter.  Ordinary jumps are represented
   by a SET whose first operand is (PC).  */
DEF_RTL_EXPR(PC, "pc", "", RTX_OBJ)

/* Used in the cselib routines to describe a value.  Objects of this
   kind are only allocated in cselib.c, in an alloc pool instead of
   in GC memory.  The only operand of a VALUE is a cselib_val_struct.  */
DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)

/* A register.  The "operand" is the register number, accessed with
   the REGNO macro.  If this number is less than FIRST_PSEUDO_REGISTER
   than a hardware register is being referred to.  The second operand
   holds the original register number - this will be different for a
   pseudo register that got turned into a hard register.  The third
   operand points to a reg_attrs structure.
   This rtx needs to have as many (or more) fields as a MEM, since we
   can change REG rtx's into MEMs during reload.  */
DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)

/* A scratch register.  This represents a register used only within a
   single insn.  It will be turned into a REG during register allocation
   or reload unless the constraint indicates that the register won't be
   needed, in which case it can remain a SCRATCH.  This code is
   marked as having one operand so it can be turned into a REG.  */
DEF_RTL_EXPR(SCRATCH, "scratch", "0", RTX_OBJ)

/* A reference to a part of another value.  The first operand is the
   complete value and the second is the byte offset of the selected part.   */
DEF_RTL_EXPR(SUBREG, "subreg", "ei", RTX_EXTRA)

/* This one-argument rtx is used for move instructions
   that are guaranteed to alter only the low part of a destination.
   Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...))
   has an unspecified effect on the high part of REG,
   but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...))
   is guaranteed to alter only the bits of REG that are in HImode.

   The actual instruction used is probably the same in both cases,
   but the register constraints may be tighter when STRICT_LOW_PART
   is in use.  */

DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", RTX_EXTRA)

/* (CONCAT a b) represents the virtual concatenation of a and b
   to make a value that has as many bits as a and b put together.
   This is used for complex values.  Normally it appears only
   in DECL_RTLs and during RTL generation, but not in the insn chain.  */
DEF_RTL_EXPR(CONCAT, "concat", "ee", RTX_OBJ)

/* (CONCATN [a1 a2 ... an]) represents the virtual concatenation of
   all An to make a value.  This is an extension of CONCAT to larger
   number of components.  Like CONCAT, it should not appear in the
   insn chain.  Every element of the CONCATN is the same size.  */
DEF_RTL_EXPR(CONCATN, "concatn", "E", RTX_OBJ)

/* A memory location; operand is the address.  The second operand is the
   alias set to which this MEM belongs.  We use `0' instead of `w' for this
   field so that the field need not be specified in machine descriptions.  */
DEF_RTL_EXPR(MEM, "mem", "e0", RTX_OBJ)

/* Reference to an assembler label in the code for this function.
   The operand is a CODE_LABEL found in the insn chain.  */
DEF_RTL_EXPR(LABEL_REF, "label_ref", "u", RTX_CONST_OBJ)

/* Reference to a named label: 
   Operand 0: label name
   Operand 1: flags (see SYMBOL_FLAG_* in rtl.h)
   Operand 2: tree from which this symbol is derived, or null.
   This is either a DECL node, or some kind of constant.  */
DEF_RTL_EXPR(SYMBOL_REF, "symbol_ref", "s00", RTX_CONST_OBJ)

/* The condition code register is represented, in our imagination,
   as a register holding a value that can be compared to zero.
   In fact, the machine has already compared them and recorded the
   results; but instructions that look at the condition code
   pretend to be looking at the entire value and comparing it.  */
DEF_RTL_EXPR(CC0, "cc0", "", RTX_OBJ)

/* ----------------------------------------------------------------------
   Expressions for operators in an rtl pattern
   ---------------------------------------------------------------------- */

/* if_then_else.  This is used in representing ordinary
   conditional jump instructions.
     Operand:
     0:  condition
     1:  then expr
     2:  else expr */
DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", RTX_TERNARY)

/* Comparison, produces a condition code result.  */
DEF_RTL_EXPR(COMPARE, "compare", "ee", RTX_BIN_ARITH)

/* plus */
DEF_RTL_EXPR(PLUS, "plus", "ee", RTX_COMM_ARITH)

/* Operand 0 minus operand 1.  */
DEF_RTL_EXPR(MINUS, "minus", "ee", RTX_BIN_ARITH)

/* Minus operand 0.  */
DEF_RTL_EXPR(NEG, "neg", "e", RTX_UNARY)

DEF_RTL_EXPR(MULT, "mult", "ee", RTX_COMM_ARITH)

/* Multiplication with signed saturation */
DEF_RTL_EXPR(SS_MULT, "ss_mult", "ee", RTX_COMM_ARITH)
/* Multiplication with unsigned saturation */
DEF_RTL_EXPR(US_MULT, "us_mult", "ee", RTX_COMM_ARITH)

/* Operand 0 divided by operand 1.  */
DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH)
/* Division with signed saturation */
DEF_RTL_EXPR(SS_DIV, "ss_div", "ee", RTX_BIN_ARITH)
/* Division with unsigned saturation */
DEF_RTL_EXPR(US_DIV, "us_div", "ee", RTX_BIN_ARITH)

/* Remainder of operand 0 divided by operand 1.  */
DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH)

/* Unsigned divide and remainder.  */
DEF_RTL_EXPR(UDIV, "udiv", "ee", RTX_BIN_ARITH)
DEF_RTL_EXPR(UMOD, "umod", "ee", RTX_BIN_ARITH)

/* Bitwise operations.  */
DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(IOR, "ior", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(XOR, "xor", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY)

/* Operand:
     0:  value to be shifted.
     1:  number of bits.  */
DEF_RTL_EXPR(ASHIFT, "ashift", "ee", RTX_BIN_ARITH) /* shift left */
DEF_RTL_EXPR(ROTATE, "rotate", "ee", RTX_BIN_ARITH) /* rotate left */
DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", RTX_BIN_ARITH) /* arithmetic shift right */
DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", RTX_BIN_ARITH) /* logical shift right */
DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", RTX_BIN_ARITH) /* rotate right */

/* Minimum and maximum values of two operands.  We need both signed and
   unsigned forms.  (We cannot use MIN for SMIN because it conflicts
   with a macro of the same name.)   The signed variants should be used
   with floating point.  Further, if both operands are zeros, or if either
   operand is NaN, then it is unspecified which of the two operands is
   returned as the result.  */

DEF_RTL_EXPR(SMIN, "smin", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(SMAX, "smax", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(UMIN, "umin", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(UMAX, "umax", "ee", RTX_COMM_ARITH)

/* These unary operations are used to represent incrementation
   and decrementation as they occur in memory addresses.
   The amount of increment or decrement are not represented
   because they can be understood from the machine-mode of the
   containing MEM.  These operations exist in only two cases:
   1. pushes onto the stack.
   2. created automatically by the life_analysis pass in flow.c.  */
DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", RTX_AUTOINC)
DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", RTX_AUTOINC)
DEF_RTL_EXPR(POST_DEC, "post_dec", "e", RTX_AUTOINC)
DEF_RTL_EXPR(POST_INC, "post_inc", "e", RTX_AUTOINC)

/* These binary operations are used to represent generic address
   side-effects in memory addresses, except for simple incrementation
   or decrementation which use the above operations.  They are
   created automatically by the life_analysis pass in flow.c.
   The first operand is a REG which is used as the address.
   The second operand is an expression that is assigned to the
   register, either before (PRE_MODIFY) or after (POST_MODIFY)
   evaluating the address.
   Currently, the compiler can only handle second operands of the
   form (plus (reg) (reg)) and (plus (reg) (const_int)), where
   the first operand of the PLUS has to be the same register as
   the first operand of the *_MODIFY.  */
DEF_RTL_EXPR(PRE_MODIFY, "pre_modify", "ee", RTX_AUTOINC)
DEF_RTL_EXPR(POST_MODIFY, "post_modify", "ee", RTX_AUTOINC)

/* Comparison operations.  The ordered comparisons exist in two
   flavors, signed and unsigned.  */
DEF_RTL_EXPR(NE, "ne", "ee", RTX_COMM_COMPARE)
DEF_RTL_EXPR(EQ, "eq", "ee", RTX_COMM_COMPARE)
DEF_RTL_EXPR(GE, "ge", "ee", RTX_COMPARE)
DEF_RTL_EXPR(GT, "gt", "ee", RTX_COMPARE)
DEF_RTL_EXPR(LE, "le", "ee", RTX_COMPARE)
DEF_RTL_EXPR(LT, "lt", "ee", RTX_COMPARE)
DEF_RTL_EXPR(GEU, "geu", "ee", RTX_COMPARE)
DEF_RTL_EXPR(GTU, "gtu", "ee", RTX_COMPARE)
DEF_RTL_EXPR(LEU, "leu", "ee", RTX_COMPARE)
DEF_RTL_EXPR(LTU, "ltu", "ee", RTX_COMPARE)

/* Additional floating point unordered comparison flavors.  */
DEF_RTL_EXPR(UNORDERED, "unordered", "ee", RTX_COMM_COMPARE)
DEF_RTL_EXPR(ORDERED, "ordered", "ee", RTX_COMM_COMPARE)

/* These are equivalent to unordered or ...  */
DEF_RTL_EXPR(UNEQ, "uneq", "ee", RTX_COMM_COMPARE)
DEF_RTL_EXPR(UNGE, "unge", "ee", RTX_COMPARE)
DEF_RTL_EXPR(UNGT, "ungt", "ee", RTX_COMPARE)
DEF_RTL_EXPR(UNLE, "unle", "ee", RTX_COMPARE)
DEF_RTL_EXPR(UNLT, "unlt", "ee", RTX_COMPARE)

/* This is an ordered NE, ie !UNEQ, ie false for NaN.  */
DEF_RTL_EXPR(LTGT, "ltgt", "ee", RTX_COMM_COMPARE)

/* Represents the result of sign-extending the sole operand.
   The machine modes of the operand and of the SIGN_EXTEND expression
   determine how much sign-extension is going on.  */
DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", RTX_UNARY)

/* Similar for zero-extension (such as unsigned short to int).  */
DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", RTX_UNARY)

/* Similar but here the operand has a wider mode.  */
DEF_RTL_EXPR(TRUNCATE, "truncate", "e", RTX_UNARY)

/* Similar for extending floating-point values (such as SFmode to DFmode).  */
DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", RTX_UNARY)
DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", RTX_UNARY)

/* Conversion of fixed point operand to floating point value.  */
DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY)

/* With fixed-point machine mode:
   Conversion of floating point operand to fixed point value.
   Value is defined only when the operand's value is an integer.
   With floating-point machine mode (and operand with same mode):
   Operand is rounded toward zero to produce an integer value
   represented in floating point.  */
DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)

/* Conversion of unsigned fixed point operand to floating point value.  */
DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)

/* With fixed-point machine mode:
   Conversion of floating point operand to *unsigned* fixed point value.
   Value is defined only when the operand's value is an integer.  */
DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", RTX_UNARY)

/* Conversions involving fractional fixed-point types without saturation,
   including:
     fractional to fractional (of different precision),
     signed integer to fractional,
     fractional to signed integer,
     floating point to fractional,
     fractional to floating point.
   NOTE: fractional can be either signed or unsigned for conversions.  */
DEF_RTL_EXPR(FRACT_CONVERT, "fract_convert", "e", RTX_UNARY)

/* Conversions involving fractional fixed-point types and unsigned integer
   without saturation, including:
     unsigned integer to fractional,
     fractional to unsigned integer.
   NOTE: fractional can be either signed or unsigned for conversions.  */
DEF_RTL_EXPR(UNSIGNED_FRACT_CONVERT, "unsigned_fract_convert", "e", RTX_UNARY)

/* Conversions involving fractional fixed-point types with saturation,
   including:
     fractional to fractional (of different precision),
     signed integer to fractional,
     floating point to fractional.
   NOTE: fractional can be either signed or unsigned for conversions.  */
DEF_RTL_EXPR(SAT_FRACT, "sat_fract", "e", RTX_UNARY)

/* Conversions involving fractional fixed-point types and unsigned integer
   with saturation, including:
     unsigned integer to fractional.
   NOTE: fractional can be either signed or unsigned for conversions.  */
DEF_RTL_EXPR(UNSIGNED_SAT_FRACT, "unsigned_sat_fract", "e", RTX_UNARY)

/* Absolute value */
DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY)

/* Square root */
DEF_RTL_EXPR(SQRT, "sqrt", "e", RTX_UNARY)

/* Swap bytes.  */
DEF_RTL_EXPR(BSWAP, "bswap", "e", RTX_UNARY)

/* Find first bit that is set.
   Value is 1 + number of trailing zeros in the arg.,
   or 0 if arg is 0.  */
DEF_RTL_EXPR(FFS, "ffs", "e", RTX_UNARY)

/* Count leading zeros.  */
DEF_RTL_EXPR(CLZ, "clz", "e", RTX_UNARY)

/* Count trailing zeros.  */
DEF_RTL_EXPR(CTZ, "ctz", "e", RTX_UNARY)

/* Population count (number of 1 bits).  */
DEF_RTL_EXPR(POPCOUNT, "popcount", "e", RTX_UNARY)

/* Population parity (number of 1 bits modulo 2).  */
DEF_RTL_EXPR(PARITY, "parity", "e", RTX_UNARY)

/* Reference to a signed bit-field of specified size and position.
   Operand 0 is the memory unit (usually SImode or QImode) which
   contains the field's first bit.  Operand 1 is the width, in bits.
   Operand 2 is the number of bits in the memory unit before the
   first bit of this field.
   If BITS_BIG_ENDIAN is defined, the first bit is the msb and
   operand 2 counts from the msb of the memory unit.
   Otherwise, the first bit is the lsb and operand 2 counts from
   the lsb of the memory unit.
   This kind of expression can not appear as an lvalue in RTL.  */
DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)

/* Similar for unsigned bit-field.
   But note!  This kind of expression _can_ appear as an lvalue.  */
DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)

/* For RISC machines.  These save memory when splitting insns.  */

/* HIGH are the high-order bits of a constant expression.  */
DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)

/* LO_SUM is the sum of a register and the low-order bits
   of a constant expression.  */
DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)

/* Describes a merge operation between two vector values.
   Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask
   that specifies where the parts of the result are taken from.  Set bits
   indicate operand 0, clear bits indicate operand 1.  The parts are defined
   by the mode of the vectors.  */
DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)

/* Describes an operation that selects parts of a vector.
   Operands 0 is the source vector, operand 1 is a PARALLEL that contains
   a CONST_INT for each of the subparts of the result vector, giving the
   number of the source subpart that should be stored into it.  */
DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)

/* Describes a vector concat operation.  Operands 0 and 1 are the source
   vectors, the result is a vector that is as long as operands 0 and 1
   combined and is the concatenation of the two source vectors.  */
DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)

/* Describes an operation that converts a small vector into a larger one by
   duplicating the input values.  The output vector mode must have the same
   submodes as the input vector mode, and the number of output parts must be
   an integer multiple of the number of input parts.  */
DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)
     
/* Addition with signed saturation */
DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)

/* Addition with unsigned saturation */
DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)

/* Operand 0 minus operand 1, with signed saturation.  */
DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)

/* Negation with signed saturation.  */
DEF_RTL_EXPR(SS_NEG, "ss_neg", "e", RTX_UNARY)
/* Negation with unsigned saturation.  */
DEF_RTL_EXPR(US_NEG, "us_neg", "e", RTX_UNARY)

/* Absolute value with signed saturation.  */
DEF_RTL_EXPR(SS_ABS, "ss_abs", "e", RTX_UNARY)

/* Shift left with signed saturation.  */
DEF_RTL_EXPR(SS_ASHIFT, "ss_ashift", "ee", RTX_BIN_ARITH)

/* Shift left with unsigned saturation.  */
DEF_RTL_EXPR(US_ASHIFT, "us_ashift", "ee", RTX_BIN_ARITH)

/* Operand 0 minus operand 1, with unsigned saturation.  */
DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)

/* Signed saturating truncate.  */
DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)

/* Unsigned saturating truncate.  */
DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)

/* Information about the variable and its location.  */
/* Changed 'te' to 'tei'; the 'i' field is for recording
   initialization status of variables.  */
DEF_RTL_EXPR(VAR_LOCATION, "var_location", "tei", RTX_EXTRA)

/* All expressions from this point forward appear only in machine
   descriptions.  */
#ifdef GENERATOR_FILE

/* Include a secondary machine-description file at this point.  */
DEF_RTL_EXPR(INCLUDE, "include", "s", RTX_EXTRA)

/* Pattern-matching operators:  */

/* Use the function named by the second arg (the string)
   as a predicate; if matched, store the structure that was matched
   in the operand table at index specified by the first arg (the integer).
   If the second arg is the null string, the structure is just stored.

   A third string argument indicates to the register allocator restrictions
   on where the operand can be allocated.

   If the target needs no restriction on any instruction this field should
   be the null string.

   The string is prepended by:
   '=' to indicate the operand is only written to.
   '+' to indicate the operand is both read and written to.

   Each character in the string represents an allocable class for an operand.
   'g' indicates the operand can be any valid class.
   'i' indicates the operand can be immediate (in the instruction) data.
   'r' indicates the operand can be in a register.
   'm' indicates the operand can be in memory.
   'o' a subset of the 'm' class.  Those memory addressing modes that
       can be offset at compile time (have a constant added to them).

   Other characters indicate target dependent operand classes and
   are described in each target's machine description.

   For instructions with more than one operand, sets of classes can be
   separated by a comma to indicate the appropriate multi-operand constraints.
   There must be a 1 to 1 correspondence between these sets of classes in
   all operands for an instruction.
   */
DEF_RTL_EXPR(MATCH_OPERAND, "match_operand", "iss", RTX_MATCH)

/* Match a SCRATCH or a register.  When used to generate rtl, a
   SCRATCH is generated.  As for MATCH_OPERAND, the mode specifies
   the desired mode and the first argument is the operand number.
   The second argument is the constraint.  */
DEF_RTL_EXPR(MATCH_SCRATCH, "match_scratch", "is", RTX_MATCH)

/* Apply a predicate, AND match recursively the operands of the rtx.
   Operand 0 is the operand-number, as in match_operand.
   Operand 1 is a predicate to apply (as a string, a function name).
   Operand 2 is a vector of expressions, each of which must match
   one subexpression of the rtx this construct is matching.  */
DEF_RTL_EXPR(MATCH_OPERATOR, "match_operator", "isE", RTX_MATCH)

/* Match a PARALLEL of arbitrary length.  The predicate is applied
   to the PARALLEL and the initial expressions in the PARALLEL are matched.
   Operand 0 is the operand-number, as in match_operand.
   Operand 1 is a predicate to apply to the PARALLEL.
   Operand 2 is a vector of expressions, each of which must match the 
   corresponding element in the PARALLEL.  */
DEF_RTL_EXPR(MATCH_PARALLEL, "match_parallel", "isE", RTX_MATCH)

/* Match only something equal to what is stored in the operand table
   at the index specified by the argument.  Use with MATCH_OPERAND.  */
DEF_RTL_EXPR(MATCH_DUP, "match_dup", "i", RTX_MATCH)

/* Match only something equal to what is stored in the operand table
   at the index specified by the argument.  Use with MATCH_OPERATOR.  */
DEF_RTL_EXPR(MATCH_OP_DUP, "match_op_dup", "iE", RTX_MATCH)

/* Match only something equal to what is stored in the operand table
   at the index specified by the argument.  Use with MATCH_PARALLEL.  */
DEF_RTL_EXPR(MATCH_PAR_DUP, "match_par_dup", "iE", RTX_MATCH)

/* Appears only in define_predicate/define_special_predicate
   expressions.  Evaluates true only if the operand has an RTX code
   from the set given by the argument (a comma-separated list).  If the
   second argument is present and nonempty, it is a sequence of digits
   and/or letters which indicates the subexpression to test, using the
   same syntax as genextract/genrecog's location strings: 0-9 for
   XEXP (op, n), a-z for XVECEXP (op, 0, n); each character applies to
   the result of the one before it.  */
DEF_RTL_EXPR(MATCH_CODE, "match_code", "ss", RTX_MATCH)

/* Appears only in define_predicate/define_special_predicate
    expressions.  The argument is a C expression to be injected at this
    point in the predicate formula.  */
DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)

/* Insn (and related) definitions.  */

/* Definition of the pattern for one kind of instruction.
   Operand:
   0: names this instruction.
      If the name is the null string, the instruction is in the
      machine description just to be recognized, and will never be emitted by
      the tree to rtl expander.
   1: is the pattern.
   2: is a string which is a C expression
      giving an additional condition for recognizing this pattern.
      A null string means no extra condition.
   3: is the action to execute if this pattern is matched.
      If this assembler code template starts with a * then it is a fragment of
      C code to run to decide on a template to use.  Otherwise, it is the
      template to use.
   4: optionally, a vector of attributes for this insn.
     */
DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)

/* Definition of a peephole optimization.
   1st operand: vector of insn patterns to match
   2nd operand: C expression that must be true
   3rd operand: template or C code to produce assembler output.
   4: optionally, a vector of attributes for this insn.

   This form is deprecated; use define_peephole2 instead.  */
DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)

/* Definition of a split operation.
   1st operand: insn pattern to match
   2nd operand: C expression that must be true
   3rd operand: vector of insn patterns to place into a SEQUENCE
   4th operand: optionally, some C code to execute before generating the
 insns.  This might, for example, create some RTX's and store them in
 elements of `recog_data.operand' for use by the vector of
 insn-patterns.
 (`operands' is an alias here for `recog_data.operand').  */
DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)

/* Definition of an insn and associated split.
   This is the concatenation, with a few modifications, of a define_insn
   and a define_split which share the same pattern.
   Operand:
   0: names this instruction.
      If the name is the null string, the instruction is in the
      machine description just to be recognized, and will never be emitted by
      the tree to rtl expander.
   1: is the pattern.
   2: is a string which is a C expression
      giving an additional condition for recognizing this pattern.
      A null string means no extra condition.
   3: is the action to execute if this pattern is matched.
      If this assembler code template starts with a * then it is a fragment of
      C code to run to decide on a template to use.  Otherwise, it is the
      template to use.
   4: C expression that must be true for split.  This may start with "&&"
      in which case the split condition is the logical and of the insn 
      condition and what follows the "&&" of this operand.
   5: vector of insn patterns to place into a SEQUENCE
   6: optionally, some C code to execute before generating the
 insns.  This might, for example, create some RTX's and store them in
 elements of `recog_data.operand' for use by the vector of
 insn-patterns.
 (`operands' is an alias here for `recog_data.operand').  
   7: optionally, a vector of attributes for this insn.  */
DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)

/* Definition of an RTL peephole operation.
   Follows the same arguments as define_split.  */
DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)

/* Define how to generate multiple insns for a standard insn name.
   1st operand: the insn name.
   2nd operand: vector of insn-patterns.
 Use match_operand to substitute an element of `recog_data.operand'.
   3rd operand: C expression that must be true for this to be available.
 This may not test any operands.
   4th operand: Extra C code to execute before generating the insns.
 This might, for example, create some RTX's and store them in
 elements of `recog_data.operand' for use by the vector of
 insn-patterns.
 (`operands' is an alias here for `recog_data.operand').  */
DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEss", RTX_EXTRA)
   
/* Define a requirement for delay slots.
   1st operand: Condition involving insn attributes that, if true,
         indicates that the insn requires the number of delay slots
  shown.
   2nd operand: Vector whose length is the three times the number of delay
  slots required.
         Each entry gives three conditions, each involving attributes.
  The first must be true for an insn to occupy that delay slot
  location.  The second is true for all insns that can be
  annulled if the branch is true and the third is true for all
  insns that can be annulled if the branch is false. 

   Multiple DEFINE_DELAYs may be present.  They indicate differing
   requirements for delay slots.  */
DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", RTX_EXTRA)

/* Define attribute computation for `asm' instructions.  */
DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)

/* Definition of a conditional execution meta operation.  Automatically
   generates new instances of DEFINE_INSN, selected by having attribute
   "predicable" true.  The new pattern will contain a COND_EXEC and the
   predicate at top-level.

   Operand:
   0: The predicate pattern.  The top-level form should match a
      relational operator.  Operands should have only one alternative.
   1: A C expression giving an additional condition for recognizing
      the generated pattern.
   2: A template or C code to produce assembler output.  */
DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "Ess", RTX_EXTRA)

/* Definition of an operand predicate.  The difference between
   DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
   not warn about a match_operand with no mode if it has a predicate
   defined with DEFINE_SPECIAL_PREDICATE.

   Operand:
   0: The name of the predicate.
   1: A boolean expression which computes whether or not the predicate
      matches.  This expression can use IOR, AND, NOT, MATCH_OPERAND,
      MATCH_CODE, and MATCH_TEST.  It must be specific enough that genrecog
      can calculate the set of RTX codes that can possibly match.
   2: A C function body which must return true for the predicate to match.
      Optional.  Use this when the test is too complicated to fit into a
      match_test expression.  */
DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)

/* Definition of a register operand constraint.  This simply maps the
   constraint string to a register class.

   Operand:
   0: The name of the constraint (often, but not always, a single letter).
   1: A C expression which evaluates to the appropriate register class for
      this constraint.  If this is not just a constant, it should look only
      at -m switches and the like.
   2: A docstring for this constraint, in Texinfo syntax; not currently
      used, in future will be incorporated into the manual's list of
      machine-specific operand constraints.  */
DEF_RTL_EXPR(DEFINE_REGISTER_CONSTRAINT, "define_register_constraint", "sss", RTX_EXTRA)

/* Definition of a non-register operand constraint.  These look at the
   operand and decide whether it fits the constraint.

   DEFINE_CONSTRAINT gets no special treatment if it fails to match.
   It is appropriate for constant-only constraints, and most others.

   DEFINE_MEMORY_CONSTRAINT tells reload that this constraint can be made
   to match, if it doesn't already, by converting the operand to the form
   (mem (reg X)) where X is a base register.  It is suitable for constraints
   that describe a subset of all memory references.

   DEFINE_ADDRESS_CONSTRAINT tells reload that this constraint can be made
   to match, if it doesn't already, by converting the operand to the form
   (reg X) where X is a base register.  It is suitable for constraints that
   describe a subset of all address references.

   When in doubt, use plain DEFINE_CONSTRAINT.  

   Operand:
   0: The name of the constraint (often, but not always, a single letter).
   1: A docstring for this constraint, in Texinfo syntax; not currently
      used, in future will be incorporated into the manual's list of
      machine-specific operand constraints.
   2: A boolean expression which computes whether or not the constraint
      matches.  It should follow the same rules as a define_predicate
      expression, including the bit about specifying the set of RTX codes
      that could possibly match.  MATCH_TEST subexpressions may make use of
      these variables:
        `op'    - the RTL object defining the operand.
        `mode'  - the mode of `op'.
 `ival'  - INTVAL(op), if op is a CONST_INT.
        `hval'  - CONST_DOUBLE_HIGH(op), if op is an integer CONST_DOUBLE.
        `lval'  - CONST_DOUBLE_LOW(op), if op is an integer CONST_DOUBLE.
        `rval'  - CONST_DOUBLE_REAL_VALUE(op), if op is a floating-point
                  CONST_DOUBLE.
      Do not use ival/hval/lval/rval if op is not the appropriate kind of
      RTL object.  */
DEF_RTL_EXPR(DEFINE_CONSTRAINT, "define_constraint", "sse", RTX_EXTRA)
DEF_RTL_EXPR(DEFINE_MEMORY_CONSTRAINT, "define_memory_constraint", "sse", RTX_EXTRA)
DEF_RTL_EXPR(DEFINE_ADDRESS_CONSTRAINT, "define_address_constraint", "sse", RTX_EXTRA)
   

/* Constructions for CPU pipeline description described by NDFAs.  */

/* (define_cpu_unit string [string]) describes cpu functional
   units (separated by comma).

   1st operand: Names of cpu functional units.
   2nd operand: Name of automaton (see comments for DEFINE_AUTOMATON).

   All define_reservations, define_cpu_units, and
   define_query_cpu_units should have unique names which may not be
   "nothing".  */
DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", RTX_EXTRA)

/* (define_query_cpu_unit string [string]) describes cpu functional
   units analogously to define_cpu_unit.  The reservation of such
   units can be queried for automaton state.  */
DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", RTX_EXTRA)

/* (exclusion_set string string) means that each CPU functional unit
   in the first string can not be reserved simultaneously with any
   unit whose name is in the second string and vise versa.  CPU units
   in the string are separated by commas.  For example, it is useful
   for description CPU with fully pipelined floating point functional
   unit which can execute simultaneously only single floating point
   insns or only double floating point insns.  All CPU functional
   units in a set should belong to the same automaton.  */
DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", RTX_EXTRA)

/* (presence_set string string) means that each CPU functional unit in
   the first string can not be reserved unless at least one of pattern
   of units whose names are in the second string is reserved.  This is
   an asymmetric relation.  CPU units or unit patterns in the strings
   are separated by commas.  Pattern is one unit name or unit names
   separated by white-spaces.
 
   For example, it is useful for description that slot1 is reserved
   after slot0 reservation for a VLIW processor.  We could describe it
   by the following construction

      (presence_set "slot1" "slot0")

   Or slot1 is reserved only after slot0 and unit b0 reservation.  In
   this case we could write

      (presence_set "slot1" "slot0 b0")

   All CPU functional units in a set should belong to the same
   automaton.  */
DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", RTX_EXTRA)

/* (final_presence_set string string) is analogous to `presence_set'.
   The difference between them is when checking is done.  When an
   instruction is issued in given automaton state reflecting all
   current and planned unit reservations, the automaton state is
   changed.  The first state is a source state, the second one is a
   result state.  Checking for `presence_set' is done on the source
   state reservation, checking for `final_presence_set' is done on the
   result reservation.  This construction is useful to describe a
   reservation which is actually two subsequent reservations.  For
   example, if we use 

      (presence_set "slot1" "slot0")

   the following insn will be never issued (because slot1 requires
   slot0 which is absent in the source state).

      (define_reservation "insn_and_nop" "slot0 + slot1")

   but it can be issued if we use analogous `final_presence_set'.  */
DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", RTX_EXTRA)

/* (absence_set string string) means that each CPU functional unit in
   the first string can be reserved only if each pattern of units
   whose names are in the second string is not reserved.  This is an
   asymmetric relation (actually exclusion set is analogous to this
   one but it is symmetric).  CPU units or unit patterns in the string
   are separated by commas.  Pattern is one unit name or unit names
   separated by white-spaces.

   For example, it is useful for description that slot0 can not be
   reserved after slot1 or slot2 reservation for a VLIW processor.  We
   could describe it by the following construction

      (absence_set "slot2" "slot0, slot1")

   Or slot2 can not be reserved if slot0 and unit b0 are reserved or
   slot1 and unit b1 are reserved .  In this case we could write

      (absence_set "slot2" "slot0 b0, slot1 b1")

   All CPU functional units in a set should to belong the same
   automaton.  */
DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", RTX_EXTRA)

/* (final_absence_set string string) is analogous to `absence_set' but
   checking is done on the result (state) reservation.  See comments
   for `final_presence_set'.  */
DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", RTX_EXTRA)

/* (define_bypass number out_insn_names in_insn_names) names bypass
   with given latency (the first number) from insns given by the first
   string (see define_insn_reservation) into insns given by the second
   string.  Insn names in the strings are separated by commas.  The
   third operand is optional name of function which is additional
   guard for the bypass.  The function will get the two insns as
   parameters.  If the function returns zero the bypass will be
   ignored for this case.  Additional guard is necessary to recognize
   complicated bypasses, e.g. when consumer is load address.  */
DEF_RTL_EXPR(DEFINE_BYPASS, "define_bypass", "issS", RTX_EXTRA)

/* (define_automaton string) describes names of automata generated and
   used for pipeline hazards recognition.  The names are separated by
   comma.  Actually it is possibly to generate the single automaton
   but unfortunately it can be very large.  If we use more one
   automata, the summary size of the automata usually is less than the
   single one.  The automaton name is used in define_cpu_unit and
   define_query_cpu_unit.  All automata should have unique names.  */
DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", RTX_EXTRA)

/* (automata_option string) describes option for generation of
   automata.  Currently there are the following options:

   o "no-minimization" which makes no minimization of automata.  This
     is only worth to do when we are debugging the description and
     need to look more accurately at reservations of states.

   o "time" which means printing additional time statistics about
      generation of automata.
  
   o "v" which means generation of file describing the result
     automata.  The file has suffix `.dfa' and can be used for the
     description verification and debugging.

   o "w" which means generation of warning instead of error for
     non-critical errors.

   o "ndfa" which makes nondeterministic finite state automata.

   o "progress" which means output of a progress bar showing how many
     states were generated so far for automaton being processed.  */
DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)

/* (define_reservation string string) names reservation (the first
   string) of cpu functional units (the 2nd string).  Sometimes unit
   reservations for different insns contain common parts.  In such
   case, you can describe common part and use its name (the 1st
   parameter) in regular expression in define_insn_reservation.  All
   define_reservations, define_cpu_units, and define_query_cpu_units
   should have unique names which may not be "nothing".  */
DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)

/* (define_insn_reservation name default_latency condition regexpr)
   describes reservation of cpu functional units (the 3nd operand) for
   instruction which is selected by the condition (the 2nd parameter).
   The first parameter is used for output of debugging information.
   The reservations are described by a regular expression according
   the following syntax:

       regexp = regexp "," oneof
              | oneof

       oneof = oneof "|" allof
             | allof

       allof = allof "+" repeat
             | repeat
 
       repeat = element "*" number
              | element

       element = cpu_function_unit_name
               | reservation_name
               | result_name
               | "nothing"
               | "(" regexp ")"

       1. "," is used for describing start of the next cycle in
       reservation.

       2. "|" is used for describing the reservation described by the
       first regular expression *or* the reservation described by the
       second regular expression *or* etc.

       3. "+" is used for describing the reservation described by the
       first regular expression *and* the reservation described by the
       second regular expression *and* etc.

       4. "*" is used for convenience and simply means sequence in
       which the regular expression are repeated NUMBER times with
       cycle advancing (see ",").

       5. cpu functional unit name which means its reservation.

       6. reservation name -- see define_reservation.

       7. string "nothing" means no units reservation.  */

DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)

/* Expressions used for insn attributes.  */

/* Definition of an insn attribute.
   1st operand: name of the attribute
   2nd operand: comma-separated list of possible attribute values
   3rd operand: expression for the default value of the attribute.  */
DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)

/* Marker for the name of an attribute.  */
DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)

/* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
   in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
   pattern.

   (set_attr "name" "value") is equivalent to
   (set (attr "name") (const_string "value"))  */
DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)

/* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
   specify that attribute values are to be assigned according to the
   alternative matched.

   The following three expressions are equivalent:

   (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
       (eq_attrq "alternative" "2") (const_string "a2")]
      (const_string "a3")))
   (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
     (const_string "a3")])
   (set_attr "att" "a1,a2,a3")
 */
DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)

/* A conditional expression true if the value of the specified attribute of
   the current insn equals the specified value.  The first operand is the
   attribute name and the second is the comparison value.  */
DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)

/* A special case of the above representing a set of alternatives.  The first
   operand is bitmap of the set, the second one is the default value.  */
DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)

/* A conditional expression which is true if the specified flag is
   true for the insn being scheduled in reorg.

   genattr.c defines the following flags which can be tested by
   (attr_flag "foo") expressions in eligible_for_delay.

   forward, backward, very_likely, likely, very_unlikely, and unlikely.  */

DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)

/* General conditional. The first operand is a vector composed of pairs of
   expressions.  The first element of each pair is evaluated, in turn.
   The value of the conditional is the second expression of the first pair
   whose first expression evaluates nonzero.  If none of the expressions is
   true, the second operand will be used as the value of the conditional.  */
DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)

#endif /* GENERATOR_FILE */

/*
Local variables:
mode:c
End:
*/

RTL 式の中では "const_int" のような小文字だけの文字列。
C 式の中では CONST_INT のような大文字の定数が使われる。

RTX

rtx ってのは　RTL eXpression の略らしい。

http://gcc.gnu.org/onlinedocs/gccint/RTL-Objects.html#RTL-Objects