Get `gn gen` to succeed on Windows

third_party/sqlite/src/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:       /* 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.
+#
+
+
+# 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 = $2
+  sub(/:/,"",name)
+  sub("\r","",name)
+  op[name] = -1
+  jump[name] = 0
+  out2_prerelease[name] = 0
+  in1[name] = 0
+  in2[name] = 0
+  in3[name] = 0
+  out2[name] = 0
+  out3[name] = 0
+  for(i=3; i<NF; i++){
+    if($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=="out2"){
+      out2[name] = 1
+    }else if(x=="out3"){
+      out3[name] = 1
+    }
+  }
+  order[n_op++] = name;
+}
+
+# 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;
+  order[n_op++] = "OP_Noop";
+  op["OP_Explain"] = -1;
+  order[n_op++] = "OP_Explain";
+  for(i=0; i<n_op; i++){
+    name = order[i];
+    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(i=0; i<n_op; i++){
+    name = order[i];
+    x = op[name]
+    a0 = a1 = a2 = a3 = a4 = a5 = a6 = a7 = 0
+    # a7 = 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( out2[name] ) a5 = 32;
+    if( out3[name] ) a6 = 64;
+    # 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_OUT2            0x0020  /* out2:  P2 is an output */"
+  print "#define OPFLG_OUT3            0x0040  /* 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 "}"
+}