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sqlite/tool/mkopcodeh.tcl
drh a02860511d Show which opcodes are jumps in the comments when generating
the opcodes.h header file.

FossilOrigin-Name: eef643a369250f1acac4c01a9b3d29068a510e5bf7fa843d565df5e2523e4dd9
2017-08-02 03:21:52 +00:00

270 lines
7.3 KiB
Tcl

#!/usr/bin/tclsh
#
# Generate the file opcodes.h.
#
# This TCL script scans a concatenation of the parse.h output file from the
# parser and the vdbe.c source file in order to generate the opcodes numbers
# for all opcodes.
#
# The lines of the vdbe.c that we are interested in are of the form:
#
# case OP_aaaa: /* same as TK_bbbbb */
#
# The TK_ comment is optional. If it is present, then the value assigned to
# the OP_ is the same as the TK_ value. If missing, the OP_ value is assigned
# a small integer that is different from every other OP_ value.
#
# We go to the trouble of making some OP_ values the same as TK_ values
# as an optimization. During parsing, things like expression operators
# are coded with TK_ values such as TK_ADD, TK_DIVIDE, and so forth. Later
# during code generation, we need to generate corresponding opcodes like
# OP_Add and OP_Divide. By making TK_ADD==OP_Add and TK_DIVIDE==OP_Divide,
# code to translate from one to the other is avoided. This makes the
# code generator smaller and faster.
#
# This script also scans for lines of the form:
#
# case OP_aaaa: /* jump, in1, in2, in3, out2-prerelease, out3 */
#
# When such comments are found on an opcode, it means that certain
# properties apply to that opcode. Set corresponding flags using the
# OPFLG_INITIALIZER macro.
#
set in stdin
set currentOp {}
set nOp 0
while {![eof $in]} {
set line [gets $in]
# Remember the TK_ values from the parse.h file.
# NB: The "TK_" prefix stands for "ToKen", not the graphical Tk toolkit
# commonly associated with TCL.
#
if {[regexp {^#define TK_} $line]} {
set tk([lindex $line 1]) [lindex $line 2]
continue
}
# Find "/* Opcode: " lines in the vdbe.c file. Each one introduces
# a new opcode. Remember which parameters are used.
#
if {[regexp {^.. Opcode: } $line]} {
set currentOp OP_[lindex $line 2]
set m 0
foreach term $line {
switch $term {
P1 {incr m 1}
P2 {incr m 2}
P3 {incr m 4}
P4 {incr m 8}
P5 {incr m 16}
}
}
set paramused($currentOp) $m
}
# Find "** Synopsis: " lines that follow Opcode:
#
if {[regexp {^.. Synopsis: (.*)} $line all x] && $currentOp!=""} {
set synopsis($currentOp) [string trim $x]
}
# Scan for "case OP_aaaa:" lines in the vdbe.c file
#
if {[regexp {^case OP_} $line]} {
set line [split $line]
set name [string trim [lindex $line 1] :]
set op($name) -1
set jump($name) 0
set in1($name) 0
set in2($name) 0
set in3($name) 0
set out2($name) 0
set out3($name) 0
for {set i 3} {$i<[llength $line]-1} {incr i} {
switch [string trim [lindex $line $i] ,] {
same {
incr i
if {[lindex $line $i]=="as"} {
incr i
set sym [string trim [lindex $line $i] ,]
set val $tk($sym)
set op($name) $val
set used($val) 1
set sameas($val) $sym
set def($val) $name
}
}
jump {set jump($name) 1}
in1 {set in1($name) 1}
in2 {set in2($name) 1}
in3 {set in3($name) 1}
out2 {set out2($name) 1}
out3 {set out3($name) 1}
}
}
set order($nOp) $name
incr nOp
}
}
# Assign numbers to all opcodes and output the result.
#
puts "/* Automatically generated. Do not edit */"
puts "/* See the tool/mkopcodeh.tcl script for details */"
foreach name {OP_Noop OP_Explain} {
set jump($name) 0
set in1($name) 0
set in2($name) 0
set in3($name) 0
set out2($name) 0
set out3($name) 0
set op($name) -1
set order($nOp) $name
incr nOp
}
# The following are the opcodes that are processed by resolveP2Values()
#
set rp2v_ops {
OP_Transaction
OP_AutoCommit
OP_Savepoint
OP_Checkpoint
OP_Vacuum
OP_JournalMode
OP_VUpdate
OP_VFilter
OP_Next
OP_NextIfOpen
OP_SorterNext
OP_Prev
OP_PrevIfOpen
}
# Assign small values to opcodes that are processed by resolveP2Values()
# to make code generation for the switch() statement smaller and faster.
#
set cnt -1
for {set i 0} {$i<$nOp} {incr i} {
set name $order($i)
if {[lsearch $rp2v_ops $name]>=0} {
incr cnt
while {[info exists used($cnt)]} {incr cnt}
set op($name) $cnt
set used($cnt) 1
set def($cnt) $name
}
}
# Assign the next group of values to JUMP opcodes
#
for {set i 0} {$i<$nOp} {incr i} {
set name $order($i)
if {$op($name)>=0} continue
if {!$jump($name)} continue
incr cnt
while {[info exists used($cnt)]} {incr cnt}
set op($name) $cnt
set used($cnt) 1
set def($cnt) $name
}
# Find the numeric value for the largest JUMP opcode
#
set mxJump -1
for {set i 0} {$i<$nOp} {incr i} {
set name $order($i)
if {$jump($name) && $op($name)>$mxJump} {set mxJump $op($name)}
}
# Generate the numeric values for all remaining opcodes
#
for {set i 0} {$i<$nOp} {incr i} {
set name $order($i)
if {$op($name)<0} {
incr cnt
while {[info exists used($cnt)]} {incr cnt}
set op($name) $cnt
set used($cnt) 1
set def($cnt) $name
}
}
set max [lindex [lsort -decr -integer [array names used]] 0]
for {set i 0} {$i<=$max} {incr i} {
if {![info exists used($i)]} {
set def($i) "OP_NotUsed_$i"
}
if {$i>$max} {set max $i}
set name $def($i)
puts -nonewline [format {#define %-16s %3d} $name $i]
set com {}
if {$jump($name)} {
lappend com "jump"
}
if {[info exists sameas($i)]} {
lappend com "same as $sameas($i)"
}
if {[info exists synopsis($name)]} {
lappend com "synopsis: $synopsis($name)"
}
if {[llength $com]} {
puts -nonewline [format " /* %-42s */" [join $com {, }]]
}
puts ""
}
if {$max>255} {
error "More than 255 opcodes - VdbeOp.opcode is of type u8!"
}
# Generate the bitvectors:
#
set bv(0) 0
for {set i 0} {$i<=$max} {incr i} {
set x 0
set name $def($i)
if {[string match OP_NotUsed* $name]==0} {
if {$jump($name)} {incr x 1}
if {$in1($name)} {incr x 2}
if {$in2($name)} {incr x 4}
if {$in3($name)} {incr x 8}
if {$out2($name)} {incr x 16}
if {$out3($name)} {incr x 32}
}
set bv($i) $x
}
puts ""
puts "/* Properties such as \"out2\" or \"jump\" that are specified in"
puts "** comments following the \"case\" for each opcode in the vdbe.c"
puts "** are encoded into bitvectors as follows:"
puts "*/"
puts "#define OPFLG_JUMP 0x01 /* jump: P2 holds jmp target */"
puts "#define OPFLG_IN1 0x02 /* in1: P1 is an input */"
puts "#define OPFLG_IN2 0x04 /* in2: P2 is an input */"
puts "#define OPFLG_IN3 0x08 /* in3: P3 is an input */"
puts "#define OPFLG_OUT2 0x10 /* out2: P2 is an output */"
puts "#define OPFLG_OUT3 0x20 /* out3: P3 is an output */"
puts "#define OPFLG_INITIALIZER \173\\"
for {set i 0} {$i<=$max} {incr i} {
if {$i%8==0} {
puts -nonewline [format "/* %3d */" $i]
}
puts -nonewline [format " 0x%02x," $bv($i)]
if {$i%8==7} {
puts "\\"
}
}
puts "\175"
puts ""
puts "/* The sqlite3P2Values() routine is able to run faster if it knows"
puts "** the value of the largest JUMP opcode. The smaller the maximum"
puts "** JUMP opcode the better, so the mkopcodeh.tcl script that"
puts "** generated this include file strives to group all JUMP opcodes"
puts "** together near the beginning of the list."
puts "*/"
puts "#define SQLITE_MX_JUMP_OPCODE $mxJump /* Maximum JUMP opcode */"