xref: /sqlite-3.40.0/tool/mkopcodeh.tcl (revision b80bb6ce)
1#!/usr/bin/tclsh
2#
3# Generate the file opcodes.h.
4#
5# This TCL script scans a concatenation of the parse.h output file from the
6# parser and the vdbe.c source file in order to generate the opcodes numbers
7# for all opcodes.
8#
9# The lines of the vdbe.c that we are interested in are of the form:
10#
11#       case OP_aaaa:      /* same as TK_bbbbb */
12#
13# The TK_ comment is optional.  If it is present, then the value assigned to
14# the OP_ is the same as the TK_ value.  If missing, the OP_ value is assigned
15# a small integer that is different from every other OP_ value.
16#
17# We go to the trouble of making some OP_ values the same as TK_ values
18# as an optimization.  During parsing, things like expression operators
19# are coded with TK_ values such as TK_ADD, TK_DIVIDE, and so forth.  Later
20# during code generation, we need to generate corresponding opcodes like
21# OP_Add and OP_Divide.  By making TK_ADD==OP_Add and TK_DIVIDE==OP_Divide,
22# code to translate from one to the other is avoided.  This makes the
23# code generator smaller and faster.
24#
25# This script also scans for lines of the form:
26#
27#       case OP_aaaa:       /* jump, in1, in2, in3, out2-prerelease, out3 */
28#
29# When such comments are found on an opcode, it means that certain
30# properties apply to that opcode.  Set corresponding flags using the
31# OPFLG_INITIALIZER macro.
32#
33
34set in stdin
35set currentOp {}
36set nOp 0
37while {![eof $in]} {
38  set line [gets $in]
39
40  # Remember the TK_ values from the parse.h file.
41  # NB:  The "TK_" prefix stands for "ToKen", not the graphical Tk toolkit
42  # commonly associated with TCL.
43  #
44  if {[regexp {^#define TK_} $line]} {
45    set tk([lindex $line 1]) [lindex $line 2]
46    continue
47  }
48
49  # Find "/* Opcode: " lines in the vdbe.c file.  Each one introduces
50  # a new opcode.  Remember which parameters are used.
51  #
52  if {[regexp {^.. Opcode: } $line]} {
53    set currentOp OP_[lindex $line 2]
54    set m 0
55    foreach term $line {
56      switch $term {
57        P1 {incr m 1}
58        P2 {incr m 2}
59        P3 {incr m 4}
60        P4 {incr m 8}
61        P5 {incr m 16}
62      }
63    }
64    set paramused($currentOp) $m
65  }
66
67  # Find "** Synopsis: " lines that follow Opcode:
68  #
69  if {[regexp {^.. Synopsis: (.*)} $line all x] && $currentOp!=""} {
70    set synopsis($currentOp) [string trim $x]
71  }
72
73  # Scan for "case OP_aaaa:" lines in the vdbe.c file
74  #
75  if {[regexp {^case OP_} $line]} {
76    set line [split $line]
77    set name [string trim [lindex $line 1] :]
78    if {$name=="OP_Abortable"} continue;  # put OP_Abortable last
79    set op($name) -1
80    set jump($name) 0
81    set in1($name) 0
82    set in2($name) 0
83    set in3($name) 0
84    set out2($name) 0
85    set out3($name) 0
86    for {set i 3} {$i<[llength $line]-1} {incr i} {
87       switch [string trim [lindex $line $i] ,] {
88         same {
89           incr i
90           if {[lindex $line $i]=="as"} {
91             incr i
92             set sym [string trim [lindex $line $i] ,]
93             set val $tk($sym)
94             set op($name) $val
95             set used($val) 1
96             set sameas($val) $sym
97             set def($val) $name
98           }
99         }
100         jump {set jump($name) 1}
101         in1  {set in1($name) 1}
102         in2  {set in2($name) 1}
103         in3  {set in3($name) 1}
104         out2 {set out2($name) 1}
105         out3 {set out3($name) 1}
106       }
107    }
108    set order($nOp) $name
109    incr nOp
110  }
111}
112
113# Assign numbers to all opcodes and output the result.
114#
115puts "/* Automatically generated.  Do not edit */"
116puts "/* See the tool/mkopcodeh.tcl script for details */"
117foreach name {OP_Noop OP_Explain OP_Abortable} {
118  set jump($name) 0
119  set in1($name) 0
120  set in2($name) 0
121  set in3($name) 0
122  set out2($name) 0
123  set out3($name) 0
124  set op($name) -1
125  set order($nOp) $name
126  incr nOp
127}
128
129# The following are the opcodes that are processed by resolveP2Values()
130#
131set rp2v_ops {
132  OP_Transaction
133  OP_AutoCommit
134  OP_Savepoint
135  OP_Checkpoint
136  OP_Vacuum
137  OP_JournalMode
138  OP_VUpdate
139  OP_VFilter
140  OP_Next
141  OP_NextIfOpen
142  OP_SorterNext
143  OP_Prev
144  OP_PrevIfOpen
145}
146
147# Assign small values to opcodes that are processed by resolveP2Values()
148# to make code generation for the switch() statement smaller and faster.
149#
150set cnt -1
151for {set i 0} {$i<$nOp} {incr i} {
152  set name $order($i)
153  if {[lsearch $rp2v_ops $name]>=0} {
154    incr cnt
155    while {[info exists used($cnt)]} {incr cnt}
156    set op($name) $cnt
157    set used($cnt) 1
158    set def($cnt) $name
159  }
160}
161
162# Assign the next group of values to JUMP opcodes
163#
164for {set i 0} {$i<$nOp} {incr i} {
165  set name $order($i)
166  if {$op($name)>=0} continue
167  if {!$jump($name)} continue
168  incr cnt
169  while {[info exists used($cnt)]} {incr cnt}
170  set op($name) $cnt
171  set used($cnt) 1
172  set def($cnt) $name
173}
174
175# Find the numeric value for the largest JUMP opcode
176#
177set mxJump -1
178for {set i 0} {$i<$nOp} {incr i} {
179  set name $order($i)
180  if {$jump($name) && $op($name)>$mxJump} {set mxJump $op($name)}
181}
182
183
184# Generate the numeric values for all remaining opcodes
185#
186for {set i 0} {$i<$nOp} {incr i} {
187  set name $order($i)
188  if {$op($name)<0} {
189    incr cnt
190    while {[info exists used($cnt)]} {incr cnt}
191    set op($name) $cnt
192    set used($cnt) 1
193    set def($cnt) $name
194  }
195}
196
197set max [lindex [lsort -decr -integer [array names used]] 0]
198for {set i 0} {$i<=$max} {incr i} {
199  if {![info exists used($i)]} {
200    set def($i) "OP_NotUsed_$i"
201  }
202  if {$i>$max} {set max $i}
203  set name $def($i)
204  puts -nonewline [format {#define %-16s %3d} $name $i]
205  set com {}
206  if {$jump($name)} {
207    lappend com "jump"
208  }
209  if {[info exists sameas($i)]} {
210    lappend com "same as $sameas($i)"
211  }
212  if {[info exists synopsis($name)]} {
213    lappend com "synopsis: $synopsis($name)"
214  }
215  if {[llength $com]} {
216    puts -nonewline [format " /* %-42s */" [join $com {, }]]
217  }
218  puts ""
219}
220
221if {$max>255} {
222  error "More than 255 opcodes - VdbeOp.opcode is of type u8!"
223}
224
225# Generate the bitvectors:
226#
227set bv(0) 0
228for {set i 0} {$i<=$max} {incr i} {
229  set x 0
230  set name $def($i)
231  if {[string match OP_NotUsed* $name]==0} {
232    if {$jump($name)}  {incr x 1}
233    if {$in1($name)}   {incr x 2}
234    if {$in2($name)}   {incr x 4}
235    if {$in3($name)}   {incr x 8}
236    if {$out2($name)}  {incr x 16}
237    if {$out3($name)}  {incr x 32}
238  }
239  set bv($i) $x
240}
241puts ""
242puts "/* Properties such as \"out2\" or \"jump\" that are specified in"
243puts "** comments following the \"case\" for each opcode in the vdbe.c"
244puts "** are encoded into bitvectors as follows:"
245puts "*/"
246puts "#define OPFLG_JUMP        0x01  /* jump:  P2 holds jmp target */"
247puts "#define OPFLG_IN1         0x02  /* in1:   P1 is an input */"
248puts "#define OPFLG_IN2         0x04  /* in2:   P2 is an input */"
249puts "#define OPFLG_IN3         0x08  /* in3:   P3 is an input */"
250puts "#define OPFLG_OUT2        0x10  /* out2:  P2 is an output */"
251puts "#define OPFLG_OUT3        0x20  /* out3:  P3 is an output */"
252puts "#define OPFLG_INITIALIZER \173\\"
253for {set i 0} {$i<=$max} {incr i} {
254  if {$i%8==0} {
255    puts -nonewline [format "/* %3d */" $i]
256  }
257  puts -nonewline [format " 0x%02x," $bv($i)]
258  if {$i%8==7} {
259    puts "\\"
260  }
261}
262puts "\175"
263puts ""
264puts "/* The sqlite3P2Values() routine is able to run faster if it knows"
265puts "** the value of the largest JUMP opcode.  The smaller the maximum"
266puts "** JUMP opcode the better, so the mkopcodeh.tcl script that"
267puts "** generated this include file strives to group all JUMP opcodes"
268puts "** together near the beginning of the list."
269puts "*/"
270puts "#define SQLITE_MX_JUMP_OPCODE  $mxJump  /* Maximum JUMP opcode */"
271