Move bundled copy of sqlite one level deeper to better separate it...

third_party/sqlite/mkopcodeh.awk

-#!/usr/bin/awk -f
-#
-# Generate the file opcodes.h.
-#
-# This AWK 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 run (infinitesimally) faster and more importantly it makes
-# the library footprint smaller.
-#
-# This script also scans for lines of the form:
-#
-#       case OP_aaaa:       /* no-push */
-#
-# When the no-push comment is found on an opcode, it means that that
-# opcode does not leave a result on the stack.  By identifying which
-# opcodes leave results on the stack it is possible to determine a
-# much smaller upper bound on the size of the stack.  This allows
-# a smaller stack to be allocated, which is important to embedded
-# systems with limited memory space.  This script generates a series
-# of "NOPUSH_MASK" defines that contain bitmaps of opcodes that leave
-# results on the stack.  The NOPUSH_MASK defines are used in vdbeaux.c
-# to help determine the maximum stack size.
-#
-
-
-# Remember the TK_ values from the parse.h file
-/^#define TK_/ {
-  tk[$2] = 0+$3
-}
-
-# Scan for "case OP_aaaa:" lines in the vdbe.c file
-/^case OP_/ {
-  name = $2
-  sub(/:/,"",name)
-  sub("\r","",name)
-  op[name] = -1
-  jump[name] = 0
-  out2_prerelease[name] = 0
-  in1[name] = 0
-  in2[name] = 0
-  in3[name] = 0
-  out3[name] = 0
-  for(i=3; i<NF; i++){
-    if($i=="same" && $(i+1)=="as"){
-      sym = $(i+2)
-      sub(/,/,"",sym)
-      op[name] = tk[sym]
-      used[op[name]] = 1
-      sameas[op[name]] = sym
-    }
-    x = $i
-    sub(",","",x)
-    if(x=="jump"){
-      jump[name] = 1
-    }else if(x=="out2-prerelease"){
-      out2_prerelease[name] = 1
-    }else if(x=="in1"){
-      in1[name] = 1
-    }else if(x=="in2"){
-      in2[name] = 1
-    }else if(x=="in3"){
-      in3[name] = 1
-    }else if(x=="out3"){
-      out3[name] = 1
-    }
-  }
-}
-
-# Assign numbers to all opcodes and output the result.
-END {
-  cnt = 0
-  max = 0
-  print "/* Automatically generated.  Do not edit */"
-  print "/* See the mkopcodeh.awk script for details */"
-  op["OP_Noop"] = -1;
-  op["OP_Explain"] = -1;
-  for(name in op){
-    if( op[name]<0 ){
-      cnt++
-      while( used[cnt] ) cnt++
-      op[name] = cnt
-    }
-    used[op[name]] = 1;
-    if( op[name]>max ) max = op[name]
-    printf "#define %-25s %15d", name, op[name]
-    if( sameas[op[name]] ) {
-      printf "   /* same as %-12s*/", sameas[op[name]]
-    } 
-    printf "\n"
-
-  }
-  seenUnused = 0;
-  for(i=1; i<max; i++){
-    if( !used[i] ){
-      if( !seenUnused ){
-        printf "\n/* The following opcode values are never used */\n"
-        seenUnused = 1
-      }
-      printf "#define %-25s %15d\n", sprintf( "OP_NotUsed_%-3d", i ), i
-    }
-  }
-
-  # Generate the bitvectors:
-  #
-  #  bit 0:     jump
-  #  bit 1:     pushes a result onto stack
-  #  bit 2:     output to p1.  release p1 before opcode runs
-  #
-  for(i=0; i<=max; i++) bv[i] = 0;
-  for(name in op){
-    x = op[name]
-    a0 = a1 = a2 = a3 = a4 = a5 = a6 = a7 = 0
-    # a8 = a9 = a10 = a11 = a12 = a13 = a14 = a15 = 0
-    if( jump[name] ) a0 = 1;
-    if( out2_prerelease[name] ) a1 = 2;
-    if( in1[name] ) a2 = 4;
-    if( in2[name] ) a3 = 8;
-    if( in3[name] ) a4 = 16;
-    if( out3[name] ) a5 = 32;
-    # bv[x] = a0+a1+a2+a3+a4+a5+a6+a7+a8+a9+a10+a11+a12+a13+a14+a15;
-    bv[x] = a0+a1+a2+a3+a4+a5+a6+a7;
-  }
-  print "\n"
-  print "/* Properties such as \"out2\" or \"jump\" that are specified in"
-  print "** comments following the \"case\" for each opcode in the vdbe.c"
-  print "** are encoded into bitvectors as follows:"
-  print "*/"
-  print "#define OPFLG_JUMP            0x0001  /* jump:  P2 holds jmp target */"
-  print "#define OPFLG_OUT2_PRERELEASE 0x0002  /* out2-prerelease: */"
-  print "#define OPFLG_IN1             0x0004  /* in1:   P1 is an input */"
-  print "#define OPFLG_IN2             0x0008  /* in2:   P2 is an input */"
-  print "#define OPFLG_IN3             0x0010  /* in3:   P3 is an input */"
-  print "#define OPFLG_OUT3            0x0020  /* out3:  P3 is an output */"
-  print "#define OPFLG_INITIALIZER {\\"
-  for(i=0; i<=max; i++){
-    if( i%8==0 ) printf("/* %3d */",i)
-    printf " 0x%02x,", bv[i]
-    if( i%8==7 ) printf("\\\n");
-  }
-  print "}"
-}