Initial commit.

1 files changed, 196 insertions, 0 deletions

diff --git a/asm.rb b/asm.rb
new file mode 100755
index 0000000..2ca9155
--- /dev/null
+++ b/asm.rb
@@ -0,0 +1,196 @@
+#!/usr/bin/ruby -w
+
+$insts = {}
+
+$next_opcode = 0
+
+def inst(pattern, vector=false, &code)
+  return if vector
+  throw "instruction with this pattern already defined" if $insts.member?(pattern)
+  $insts[pattern] = $next_opcode
+  $next_opcode += 1
+end
+
+load "insts.rb"
+
+$labels = {}
+$pc = 0
+
+ARGF.each_line do | line |
+  line.chomp!
+  line.gsub!(/^\s+/, "")
+  line.gsub!(/#.*/, "")
+  line.gsub!(/\s+$/, "")
+
+  next if line == ""
+
+  if line =~ /^([a-zA-Z_][a-zA-Z0-9_]*):$/
+    $labels[$1] = $pc
+    $stdout.write("\t// #{line}\n")
+    next
+  elsif line =~ /^\.origin\s+((?:0x[0-9a-fA-F]+)?(?:\d+))$/
+    $pc = $1.to_i(0)
+    $stdout.write("@#{$pc.to_s(16)}\t// #{line}\n")
+    next
+  elsif line =~ /^\.bytes?\s+(.*)$/
+    data = $1.split(/\s+/)
+    data.map { | x | throw "invalid byte #{x}" unless x =~ /^-?(?:(?:0x[0-9a-fA-F]+)|(?:\d+))$/ }
+    data = data.map { | x | x.to_i(0) }
+    data = data.map { | x | x < 0 ? x + 0x100 : x }
+    data.map { | x | throw "invalid byte 0x#{x.to_s(16)}" unless x >= 0 && x <= 0xff }
+    data = data.map { | x | x.to_s(16).rjust(2, "0") }
+    $pc += data.size
+    $stdout.write("#{data.join(" ")}\t// #{line}\n")
+    next
+  elsif line =~ /^\.shorts?\s+(.*)$/
+    data = $1.split(/\s+/)
+    data.map { | x | throw "invalid short #{x}" unless x =~ /^-?(?:(?:0x[0-9a-fA-F]+)|(?:\d+))$/ }
+    data = data.map { | x | x.to_i(0) }
+    data = data.map { | x | x < 0 ? x + 0x10000 : x }
+    data.map { | x | throw "invalid short 0x#{x.to_s(16)}" unless x >= 0 && x <= 0xffff }
+    data = data.flat_map { | x | [x & 0xff, x >> 8] }
+    data = data.map { | x | x.to_s(16).rjust(2, "0") }
+    $pc += data.size
+    $stdout.write("#{data.join(" ")}\t// #{line}\n")
+    next
+  elsif line =~ /^\.longs?\s+(.*)$/
+    data = $1.split(/\s+/)
+    data.map { | x | throw "invalid long #{x}" unless x =~ /^-?(?:(?:0x[0-9a-fA-F]+)|(?:\d+))$/ }
+    data = data.map { | x | x.to_i(0) }
+    data = data.map { | x | x < 0 ? x + 0x100000000 : x }
+    data.map { | x | throw "invalid long 0x#{x.to_s(16)}" unless x >= 0 && x <= 0xffffffff }
+    data = data.flat_map { | x | [x & 0xff, (x >> 8) & 0xff, (x >> 16) & 0xff, x >> 24] }
+    data = data.map { | x | x.to_s(16).rjust(2, "0") }
+    $pc += data.size
+    $stdout.write("#{data.join(" ")}\t// #{line}\n")
+    next
+  elsif line =~ /^\.quads?\s+(.*)$/
+    data = $1.split(/\s+/)
+    data.map { | x | throw "invalid quad #{x}" unless x =~ /^-?(?:(?:0x[0-9a-fA-F]+)|(?:\d+))$/ }
+    data = data.map { | x | x.to_i(0) }
+    data = data.map { | x | x < 0 ? x + 0x10000000000000000 : x }
+    data.map { | x | throw "invalid quad 0x#{x.to_s(16)}" unless x >= 0 && x <= 0xffffffffffffffff }
+    data = data.flat_map { | x | [x & 0xff, (x >> 8) & 0xff, (x >> 16) & 0xff, (x >> 24) & 0xff, (x >> 32) & 0xff, (x >> 40) & 0xff, (x >> 48) & 0xff, x >> 56] }
+    data = data.map { | x | x.to_s(16).rjust(2, "0") }
+    $pc += data.size
+    $stdout.write("#{data.join(" ")}\t// #{line}\n")
+    next
+  end
+
+  parts = line.split(/\s+/)
+
+  patterns = [parts.shift]
+  values = []
+  parts.each do | part |
+    case part
+      when /^(-?(?:(?:0x[0-9a-fA-F]+)|(?:\d+)))$/
+        patterns << "#"
+        values << $1.to_i(0)
+      when /^([a-zA-Z_][a-zA-Z0-9_]+)$/
+        throw "unknown label #{$1}" unless $labels.member?($1)
+        patterns << "#"
+        values << $labels[$1]
+      when /^\$(-?(?:(?:0x[0-9a-fA-F]+)|(?:\d+)))$/
+        patterns << "$"
+        values << $1.to_i(0)
+      when /^\[(-?(?:(?:0x[0-9a-fA-F]+)|(?:\d+)))\]$/
+        patterns << "[#]"
+        values << $1.to_i(0)
+      when /^\[([a-zA-Z_][a-zA-Z0-9_]+)\]$/
+        throw "unknown label #{$1}" unless $labels.member?($1)
+        patterns << "[#]"
+        values << $labels[$1]
+      when /^\[\$(-?(?:(?:0x[0-9a-fA-F]+)|(?:\d+)))\]$/
+        patterns << "[$]"
+        values << $1.to_i(0)
+      else
+        throw "invalid part #{part}"
+    end
+  end
+
+  pattern = patterns.join(" ")
+  throw "unknown instruction pattern #{pattern}" unless $insts.member?(pattern)
+  opcode = $insts[pattern]
+
+  # Encoding format:
+  #   +-+-+-+-+-+-+-+-+
+  #   |M|I|SEL| SHIFT |
+  #   +-+-+-+-+-+-+-+-+
+  # M = More data after this
+  # I = Invert this field before shifting
+  # SEL = Field selector (0=opcode, 2=A, 3=B)
+  # SHIFT = Data to shift in
+
+  # This gives us these common first nibbles:
+  #   0   last opcode byte
+  #   8   extended opcode byte
+  #   A   operand A byte
+  #   B   operand B byte
+  #   E   operand A byte (with inversion)
+  #   F   operand B byte (with inversion)
+
+  space = false
+  values.each_with_index do | value, idx |
+    inverted = value < 0
+    if inverted
+      value *= -1
+      value -= 1
+    end
+    nibbles = []
+    while value != 0
+      nibbles << (value & 0xf).to_s(16)
+      value = value >> 4
+    end
+    if inverted and nibbles.empty?
+      nibbles << "f"
+    end
+    nibbles.reverse!
+    if idx == 0
+      if inverted
+        $stdout.write(" ") if space
+        $stdout.write("e#{nibbles.shift}")
+        $pc += 1
+        space = true
+      end
+      nibbles.each do | nibble |
+        $stdout.write(" ") if space
+        $stdout.write("a#{nibble}")
+        $pc += 1
+        space = true
+      end
+    elsif idx == 1
+      if inverted
+        $stdout.write(" ") if space
+        $stdout.write("f#{nibbles.shift}")
+        $pc += 1
+        space = true
+      end
+      nibbles.each do | nibble |
+        $stdout.write(" ") if space
+        $stdout.write("b#{nibble}")
+        $pc += 1
+        space = true
+      end
+    else
+      throw "don't know how to encode this many fields"
+    end
+  end
+
+  nibbles = []
+  while opcode != 0
+    nibbles << (opcode & 0xf).to_s(16)
+    opcode = opcode >> 4
+  end
+  nibbles << "0" if nibbles.empty?
+  last = nibbles.shift
+  nibbles.reverse!
+  nibbles.each do | nibble |
+    $stdout.write(" ") if space
+    $stdout.write("8#{nibble}")
+    $pc += 1
+    space = true
+  end
+  $stdout.write(" ") if space
+  $stdout.write("0#{last}\t// #{line}\n")
+  $pc += 1
+end