re-worked assemlber to load from file and have real labels

assembler.rb

@@ -1,28 +1,8 @@
 
-$bytes = []
-
-def zero_fill(pos)
-	while ($bytes.length <= pos) do
-		$bytes.push(0)
-	end
-end
-
-def word(i)
-	$bytes.push((i & 0x000000ff),
-		(i & 0x0000ff00) >> 8,
-		(i & 0x00ff0000) >> 16,
-		(i & 0xff000000) >> 24)
-end
-
-def string(s)
-	$bytes.push *s.bytes
-	while (($bytes.length % 4) != 0) do
-		$bytes.push 0
-	end
-end
-
+# assembler.rb
 
 # # # REGISTER NAMES # # #
+def r0() 0 end # zero
 def at() 1 end # assembler temporary
 
 # subroutine return values, may be changed by subroutines
@@ -55,6 +35,71 @@ def sp() 29 end # stack pointer
 def fp() 30 end # frame pointer
 def ra() 31 end # return address
 
+class Assembler
+	def initialize(base, size)
+		@base_addr = base
+		@file_size = size
+	end
+
+	def inspect
+		"(Assembler base_addr:0x#{@base_addr.to_s 16} file_size:0x#{@file_size.to_s 16})"
+	end
+
+	# TODO: Sub-labels
+
+	def label(l)
+		return if @first_pass == false
+		raise "error redefinition of label #{l.to_s}" if @labels.member?(l.to_s)
+		@labels[l.to_s] = @bytes.length + @base_addr
+	end
+
+	def method_missing(m, *args, &block)
+		return 0 if @first_pass
+		if m.to_s[0, 2] == "l_" then
+			return @labels[m.to_s[2..]] if @labels.member?(m.to_s[2..])
+			raise "label doesn't exist #{m.to_s}"
+		else
+			super
+		end
+	end
+
+	def assemble(source)
+		@first_pass = true
+		@labels = {}
+		@bytes = []
+		binding.eval source
+
+		@first_pass = false
+		@bytes = []
+		binding.eval source
+
+		puts "assembled 0x#{@bytes.length.to_s 16} (#{@bytes.length}) bytes"
+		raise "CODE IS GREATER THAN FILESIZE" if @bytes.length > @file_size
+		zero_fill @file_size - 1
+
+		return @bytes
+	end
+
+	def zero_fill(pos)
+		while (@bytes.length <= pos) do
+			@bytes.push(0)
+		end
+	end
+	
+	def word(i)
+		@bytes.push((i & 0x000000ff),
+			(i & 0x0000ff00) >> 8,
+			(i & 0x00ff0000) >> 16,
+			(i & 0xff000000) >> 24)
+	end
+	
+	def string(s)
+		@bytes.push *s.bytes
+		@bytes.push 0 # null terminate
+		while ((@bytes.length % 4) != 0) do
+			@bytes.push 0
+		end
+	end
 
 
 	# # # INSTRUCTIONS # # #
@@ -120,7 +165,33 @@ def sw(src, offset, dest)
 		word op
 	end
 
+	# add immediate unsigned
+	def addiu(src, val, dest)
+		#      oooooo sssss ddddd iiiiiiii iiiiiiii
+		op = 0b001001_00000_00000_00000000_00000000
+		op |= (src & 0b11111) << 21
+		op |= (val & 0xffff)
+		op |= (dest & 0b11111) << 16
+		word op
+	end
 
+	# add immediate
+	def addi(src, val, dest)
+		#      oooooo sssss ddddd iiiiiiii iiiiiiii
+		op = 0b001000_00000_00000_00000000_00000000
+		op |= (src & 0b11111) << 21
+		op |= (val & 0xffff)
+		op |= (dest & 0b11111) << 16
+		word op
+	end
+
+	# jump register
+	def jr(reg)
+		#      oooooo rrrrr ----- ----- ----- oooooo
+		op = 0b000000_00000_00000_00000_00000_001000
+		op |= (reg & 0b11111) << 21
+		word op
+	end
 
 	# # # PSEUDO-INSTRUCTIONS # # #
 	def nop
@@ -133,117 +204,27 @@ def lwi(val, dest)
 		ori dest, val, dest
 	end
 
-
-
-
-
-def label
-	return $bytes.length + $base_addr
 end
 
-# this is a terrible idea and im doing it
-#$labels = {}
-#def method_missing(m, *args)
-#	puts m.to_s
-#	super
-#end
-
 
 # # # CONSTANTS # # #
-$base_addr = 0x80010000 # 0x10000 # 0x80010000
-$file_size = 0x800 * 3
-$gp0 = 0x1F801810
-$gp1 = 0x1F801814
+base_addr = 0x80010000 # 0x10000 # 0x80010000
+file_size = 0x800 * 3
 
-# # # EXE HEADER # # #
-string "PS-X EXE"
-zero_fill 0x00f
-word $base_addr # initial pc
-word 0x00000000 # initial GP/R28
-word $base_addr # destintation address in RAM
-word $file_size # file size excluding header (must be N * 0x800)
-word 0x00000000 # Unknown/Unused
-word 0x00000000 # Unknown/Unused
-word 0x00000000 # Memfill start address
-word 0x00000000 # Memfill size in bytes
-word 0x801ffff0 # Initial SP/R29 & FP/R30 Base
-word 0x00000000 # Initial SP/R29 & FP/R30 Offs
-zero_fill 0x4b # Reserved for A(43h) Function
-# Ascii marker would go here
-zero_fill 0x7ff
-$exe_header = $bytes[0..]
-$bytes = []
+f = File.new "exe-header.asm.rb", "r"
+exe_header = Assembler.new(base_addr, 0x800).assemble f.read
+f.close
 
-
-
-
-# # # PROGRAM CODE # # #
-nop
-
-# ops should always be in format of
-# src [args] -> dest
-
-# THIS IS NEEDED
-lwi $gp1, t0
-lwi 0x03_00_00_00, t1 # display enable
-sw t1, 0, t0
-
-lwi $gp0, t0
-
-lwi 0xe1_000000 + 0b0_0_0_1_0_01_00_0_0000, t1
-sw t1, 0, t0
-
-# THIS IS NEEDED
-lwi 0xe4_000000 + (640) + (480 << 10), t1 # Drawing Area bottom right
-sw t1, 0, t0
-
-def line(st, en)
-	lwi 0x40_ffffff, t1 # monochrome line, color ffffff
-	sw t1, 0, t0
-
-	lwi st, t1 # line vert 1
-	sw t1, 0, t0
-
-	lwi en, t1 # line vert 2
-	sw t1, 0, t0
-end
-
-l_end_loop = label
-line 0x0010_0010, 0x0030_0030
-line 0x0030_0030, 0x0060_0000
-line 0x0060_0000, 0x00f0_0060
-
-nop ; nop ; nop ; nop
-nop ; nop ; nop ; nop
-nop ; nop ; nop ; nop
-nop ; nop ; nop ; nop
-
-# l_end_loop = label
-nop
-jmp l_end_loop
-nop
-
-
-
-
-
-
-
-string "this is a test lol"
-
-
-
-
-zero_fill $file_size - 1
+f = File.new "main.asm.rb", "r"
+binary = Assembler.new(base_addr, file_size).assemble f.read
+f.close
 
 f = File.new "LOADTHIS.EXE", "wb"
-f.write $exe_header.pack("C*")
-f.write $bytes.pack("C*")
+f.write exe_header.pack("C*")
+f.write binary.pack("C*")
 f.close
 
 
 
 
 
-
-

exe-header.asm.rb

@@ -0,0 +1,18 @@
+
+# exe-header.asm.rb
+
+string "PS-X EXE"
+zero_fill 0x00f
+word @base_addr # initial pc
+word 0x00000000 # initial GP/R28
+word @base_addr # destintation address in RAM
+word @file_size # file size excluding header (must be N * 0x800)
+word 0x00000000 # Unknown/Unused
+word 0x00000000 # Unknown/Unused
+word 0x00000000 # Memfill start address
+word 0x00000000 # Memfill size in bytes
+word 0x801ffff0 # Initial SP/R29 & FP/R30 Base
+word 0x00000000 # Initial SP/R29 & FP/R30 Offs
+zero_fill 0x4b # Reserved for A(43h) Function
+# Ascii marker would go here
+zero_fill 0x7ff

main.asm.rb

@@ -0,0 +1,78 @@
+
+# main.asm.rb
+
+$gp0 = 0x1F801810
+$gp1 = 0x1F801814
+
+jmp l_start
+nop
+
+label :hello_world
+	string "ello wrld!\n"
+
+label :printf
+	addiu r0, 0xa0, at # address of bios func
+	jr at
+	addiu r0, 0x3f, t1 # printf number
+
+label :draw_line
+	# todo: draw line function, take args in a0 - a3
+	# tood: implement shift left so we can use that
+	lwi $gp0, t0
+
+	lwi 0x40_ffffff, t1 # monochrome line, color ffffff
+	sw t1, 0, t0
+
+	# lwi st, t1 # line vert 1
+	sw t1, 0, t0
+
+	# lwi en, t1 # line vert 2
+	sw t1, 0, t0
+
+label :start
+	nop ; nop ; nop ; nop
+
+	# THIS IS NEEDED
+	lwi $gp1, t0
+	lwi 0x03_00_00_00, t1 # display enable
+	sw t1, 0, t0
+
+	lwi $gp0, t0
+
+	lwi 0xe1_000000 + 0b0_0_0_1_0_01_00_0_0000, t1
+	sw t1, 0, t0
+
+	# THIS IS NEEDED
+	lwi 0xe4_000000 + (640) + (480 << 10), t1 # Drawing Area bottom right
+	sw t1, 0, t0
+
+	def line(st, en)
+		lwi 0x40_ffffff, t1 # monochrome line, color ffffff
+		sw t1, 0, t0
+
+		lwi st, t1 # line vert 1
+		sw t1, 0, t0
+
+		lwi en, t1 # line vert 2
+		sw t1, 0, t0
+	end
+
+	line 0x0010_0010, 0x0030_0030
+	line 0x0030_0030, 0x0060_0000
+	line 0x0060_000a, 0x00f0_0060
+
+	lwi l_hello_world, a0
+	jal l_printf
+	addiu sp, -16, sp # delay slot
+	addiu sp, 16, sp
+
+label :end_loop
+	lwi l_end_loop, t9
+	jr t9
+	nop
+
+
+
+
+
+