1465 lines
28 KiB
Plaintext
1465 lines
28 KiB
Plaintext
(*
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s1 - Contains the current position in the source text.
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- The compiler expects valid input, otherwise it will generate invalid
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assembly or hang. There is no error checking, no semantic analysis, no
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type checking.
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- Imports with only a module name without package, e.g.
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"import dummy", can be parsed, but are ignored.
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- No loops. Only labels and goto.
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- Only unsigned number literals are supported (in decimal or
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hexadecimal format).
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- Comments are accepted only at the end of a line.
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*)
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program
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import dummy
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const
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SOURCE_BUFFER_SIZE := 81920
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var
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source_code: [81920]Byte
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(* Ignores the import. *)
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proc _compile_import()
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var loca0: Word
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begin
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_advance(6)
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_skip_spaces()
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loca0 := _read_token()
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_advance(loca0) (* Skip the imported module name. *)
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end
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proc _build_binary_expression()
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var loca0, loca4, loca8: Word
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begin
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_build_expression(0)
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loca4 := 0x2c306120 (* _a0, *)
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loca8 := 0x0a316120 (* _a1\n *)
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_skip_spaces()
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call _read_token
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sw a0, 20(sp)
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li t0, 0x26 # &
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sw t0, 16(sp)
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mv a0, s1
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lw a1, 20(sp)
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addi a2, sp, 16
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call _token_compare
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beqz a0, .L_build_binary_expression_and
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li t0, 0x726f # or
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sw t0, 16(sp)
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mv a0, s1
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lw a1, 20(sp)
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addi a2, sp, 16
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call _token_compare
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beqz a0, .L_build_binary_expression_or
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li t0, 0x3d # =
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sw t0, 16(sp)
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mv a0, s1
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lw a1, 20(sp)
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addi a2, sp, 16
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call _token_compare
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beqz a0, .L_build_binary_expression_equal
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li t0, 0x2b # +
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sw t0, 16(sp)
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mv a0, s1
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lw a1, 20(sp)
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addi a2, sp, 16
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call _token_compare
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beqz a0, .L_build_binary_expression_plus
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li t0, 0x2d # -
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sw t0, 16(sp)
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mv a0, s1
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lw a1, 20(sp)
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addi a2, sp, 16
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call _token_compare
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beqz a0, .L_build_binary_expression_minus
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goto .Lbuild_binary_expression_end
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.L_build_binary_expression_equal
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_advance(1) (* Skip =. *)
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_build_expression(1)
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_write_out(@loca0, 3)
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_write_out(@loca4, 4)
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_write_out(@loca4, 4)
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_write_out(@loca8, 4)
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loca0 := 0x7a716573 (* seqz *)
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_write_out(@loca0, 4)
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_write_out(@loca4, 4)
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_write_out(@loca4, 4)
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goto .Lbuild_binary_expression_end
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.L_build_binary_expression_and
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_advance(1) (* Skip &. *)
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_build_expression(1)
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loca0 := 0x646e61 (* and *)
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_write_out(@loca0, 3)
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_write_out(@loca4, 4)
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_write_out(@loca4, 4)
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_write_out(@loca8, 4)
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goto .Lbuild_binary_expression_end
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.L_build_binary_expression_or
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_advance(2) (* Skip or. *)
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_build_expression(1)
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loca0 := 0x726f (* or *)
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_write_out(@loca0, 2)
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_write_out(@loca4, 4)
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_write_out(@loca4, 4)
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_write_out(@loca8, 4)
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goto .Lbuild_binary_expression_end
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.L_build_binary_expression_plus
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_advance(1) (* Skip +. *)
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_build_expression(1)
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loca0 := 0x646461 (* add *)
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_write_out(@loca0, 3)
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_write_out(@loca4, 4)
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_write_out(@loca4, 4)
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_write_out(@loca8, 4)
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goto .Lbuild_binary_expression_end
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.L_build_binary_expression_minus
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_advance(1) (* Skip -. *)
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_build_expression(1)
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loca0 := 0x627573 (* sub *)
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_write_out(@loca0, 3)
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_write_out(@loca4, 4)
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_write_out(@loca4, 4)
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_write_out(@loca8, 4)
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.Lbuild_binary_expression_end
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end
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(*
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Evalutes an expression and saves the result in a0.
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a0 - X in aX, the register number to save the result.
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*)
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proc _build_expression()
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var
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loca20, loca28, loca8: Word
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loca24: ^Byte
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begin
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addi a0, a0, '0' # Make the register number to a character.
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sw a0, 28(sp) # And save it.
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_skip_spaces()
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loca20 := _read_token()
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loca24 := _current()
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addi a0, s1, 0
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lbu a0, (a0)
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li t0, '@'
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beq a0, t0, .Lbuild_expression_address
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addi a0, s1, 0
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lbu a0, (a0)
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call _is_digit
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bnez a0, .Lbuild_expression_literal
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addi a0, s1, 0
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lbu a0, (a0)
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li t0, '_'
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beq a0, t0, .Lbuild_expression_call
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li t0, 0x61636f6c # loca
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sw t0, 8(sp)
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mv a0, s1
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addi a1, sp, 8
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li a2, 4
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call _memcmp
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beqz a0, .Lbuild_expression_identifier
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(* Named identifier. *)
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loca8 := 0x6120616c (* la a *)
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_write_out(@loca8, 4)
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loca8 := 0x00202c00 or loca28
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_write_out(@loca8, 3)
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_write_out(loca24, loca20)
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_put_char(0x0a)
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goto .Lbuild_expression_advance
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.Lbuild_expression_address
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loca8 := 0x69646461 (* addi *)
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_write_out(@loca8, 4)
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loca8 := 0x6120 (* _a *)
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_write_out(@loca8, 2)
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_put_char(loca28)
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loca8 := 0x7073202c (* , sp *)
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_write_out(@loca8, 4)
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loca8 := 0x202c (* ,_ *)
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_write_out(@loca8, 2)
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_advance(1) (* Skip @. *)
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_skip_spaces()
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loca24 := _current()
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loca20 := _read_token()
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lw a0, 24(sp)
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lw a1, 20(sp)
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addi a0, a0, 4 # Skip the "loca" variable prefix.
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addi a1, a1, -4 # Skip the "loca" variable prefix.
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call _write_out
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_put_char(0xa)
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goto .Lbuild_expression_advance
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.Lbuild_expression_identifier
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lw t1, 28(sp)
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li t0, 0x00202c00 # \0,_
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or t0, t0, t1
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sw t0, 8(sp)
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li t0, 0x6120776c # lw a
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sw t0, 4(sp)
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addi a0, sp, 4
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li a1, 7
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call _write_out
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lw a0, 24(sp)
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lw a1, 20(sp)
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addi a0, a0, 4 # Skip the "loca" variable prefix.
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addi a1, a1, -4 # Skip the "loca" variable prefix.
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call _write_out
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li t0, 0x0a # \n
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sw t0, 8(sp)
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li t0, 0x29707328 # (sp)
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sw t0, 4(sp)
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addi a0, sp, 4
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li a1, 5
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call _write_out
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goto .Lbuild_expression_advance
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.Lbuild_expression_call
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_advance(loca20)
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_advance(1)
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_compile_call(loca24, loca20)
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goto .Lbuild_expression_end
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.Lbuild_expression_literal
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lw t1, 28(sp)
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li t0, 0x00202c00 # \0,_
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or t0, t0, t1
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sw t0, 8(sp)
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li t0, 0x6120696c # li a
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sw t0, 4(sp)
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addi a0, sp, 4
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li a1, 7
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call _write_out
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_write_out(loca24, loca20)
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_put_char(0x0a) # \n
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goto .Lbuild_expression_advance
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.Lbuild_expression_advance
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_advance(loca20)
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.Lbuild_expression_end
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end
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(*
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Compiles a statement beginning with an identifier.
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Left values should be variables named "loca n", where n is the offset
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of the variable on the stack, like loca8 or loca4.
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*)
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proc _compile_identifier()
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var
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loca0, loca16, loca8: Word
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loca20, loca12: ^Byte
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begin
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(* Save the pointer to the identifier and its length on the stack. *)
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loca20 := _current()
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loca16 := _read_token()
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_advance(loca16)
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_skip_spaces()
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(* Save the pointer and the length of the token following the identifier. *)
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loca12 := _current()
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loca8 := _read_token()
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_advance(loca8) # Skip that token.
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_skip_spaces()
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li t0, 0x3d3a # :=
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sw t0, 4(sp)
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lw a0, 12(sp)
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lw a1, 8(sp)
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addi a2, sp, 4
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call _token_compare
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beqz a0, .Lcompile_identifier_assign
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lw t0, 12(sp)
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lbu t0, (t0)
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li t1, 0x28 # (
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beq t0, t1, .Lcompile_identifier_call
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goto .Lcompile_identifier_end
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.Lcompile_identifier_call
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_compile_call(loca20, loca16)
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goto .Lcompile_identifier_end
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.Lcompile_identifier_assign
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_build_binary_expression()
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loca0 := 0x61207773 (* sw a *)
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_write_out(@loca0, 4)
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loca0 := 0x202c30 (* 0,_ *)
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_write_out(@loca0, 3)
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lw a0, 20(sp)
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lw a1, 16(sp)
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addi a0, a0, 4 # Skip the "loca" variable prefix.
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addi a1, a1, -4 # Skip the "loca" variable prefix.
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call _write_out
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loca0 := 0x29707328 (* (sp) *)
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_write_out(@loca0, 4)
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_put_char(0x0a) (* \n *)
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goto .Lcompile_identifier_end
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.Lcompile_identifier_end
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end
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(*
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Compiles a procedure call. Expects s1 to point to the first argument.
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a0 - Pointer to the procedure name.
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a1 - Length of the procedure name.
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Returns the procedure result in a0.
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*)
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proc _compile_call(loca84: ^Byte, loca80: Word)
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var
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loca0, loca12: Word
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begin
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loca12 := 0 (* Argument count for a procedure call. *)
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.Lcompile_call_paren
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_skip_spaces()
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lbu t0, (s1)
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li t1, 0x29 # )
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beq t0, t1, .Lcompile_call_complete
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.Lcompile_call_argument
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_build_expression(0)
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loca0 := 0x61207773 (* sw a *)
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_write_out(@loca0, 4)
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loca0 := 0x202c30 (* 0,_ *)
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_write_out(@loca0, 3)
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lw t0, 12(sp) # Argument count for a procedure call.
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(*
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Only 6 arguments are supported with a0-a5.
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Save all arguments on the stack so they aren't overriden afterwards.
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The offset on the stack always has two digits in this case.
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*)
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li t1, -4
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mul t1, t0, t1
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addi t1, t1, 60
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li t2, 10
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div t3, t1, t2
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rem t4, t1, t2
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addi t3, t3, '0'
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addi t4, t4, '0'
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sw t3, 8(sp)
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sw t4, 4(sp)
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addi a0, sp, 8
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li a1, 1
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call _write_out
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addi a0, sp, 4
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li a1, 1
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call _write_out
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li t0, 0x0a # \n
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sw t0, 8(sp)
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li t0, 0x29707328 # (sp)
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sw t0, 4(sp)
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addi a0, sp, 4
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li a1, 5
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call _write_out
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_skip_spaces()
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lbu t0, (s1)
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li t1, ','
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bne t0, t1, .Lcompile_call_paren
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lw t0, 12(sp) # Argument count for a procedure call.
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addi t0, t0, 1
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sw t0, 12(sp)
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_advance(1) (* Skip the comma between the arguments. *)
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goto .Lcompile_call_argument
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.Lcompile_call_complete
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loca12 := 0
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.Lcompile_call_restore
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(*
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Just go through all a0-a5 registers and read them from stack.
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If this stack value contains garbage, the procedure just shouldn't use it.
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*)
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lw t0, 12(sp)
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li t1, 5
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bgt t0, t1, .Lcompile_call_perform
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li t0, 0x6120776c # lw a
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sw t0, 4(sp)
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addi a0, sp, 4
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li a1, 4
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call _write_out
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lw t0, 12(sp) # Argument count for a procedure call.
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li t1, -4
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mul t1, t0, t1
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addi t1, t1, 60
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li t2, 10
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div t3, t1, t2
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rem t4, t1, t2
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addi t3, t3, '0'
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addi t4, t4, '0'
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addi t0, t0, '0'
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li t5, 0x0a # \n
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sb t5, 11(sp)
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li t5, 0x29707328 # (sp)
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sw t5, 7(sp)
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sb t4, 6(sp)
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sb t3, 5(sp)
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li t5, 0x202c # ,_
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sh t5, 3(sp)
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sb t0, 2(sp)
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addi a0, sp, 2
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li a1, 10
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call _write_out
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loca12 := loca12 + 1
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goto .Lcompile_call_restore
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.Lcompile_call_perform
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loca0 := 0x6c6c6163
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_write_out(@loca0, 4)
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_put_char(0x20) (* _ *)
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_write_out(loca84, loca80)
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_put_char(0x0a) (* \n *)
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_skip_spaces()
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_advance(1) (* Skip the close paren. *)
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end
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(*
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Reads a token and returns its length in a0.
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_read_token doesn't change s1, it finds the length of the token s1 is pointing to.
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*)
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proc _read_token()
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var loca4: Word
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begin
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lbu t0, (s1) # t0 = Current character.
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loca4 := 0
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li t1, '.'
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beq t0, t1, .Ltoken_character_single
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li t1, ','
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beq t0, t1, .Ltoken_character_single
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li t1, ':'
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beq t0, t1, .Ltoken_character_colon
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li t1, ';'
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beq t0, t1, .Ltoken_character_single
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li t1, '('
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beq t0, t1, .Ltoken_character_single
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li t1, ')'
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beq t0, t1, .Ltoken_character_single
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li t1, '['
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beq t0, t1, .Ltoken_character_single
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li t1, ']'
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beq t0, t1, .Ltoken_character_single
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li t1, '^'
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beq t0, t1, .Ltoken_character_single
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li t1, '&'
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beq t0, t1, .Ltoken_character_single
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li t1, '='
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beq t0, t1, .Ltoken_character_single
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li t1, '+'
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beq t0, t1, .Ltoken_character_single
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li t1, '-'
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beq t0, t1, .Ltoken_character_single
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li t1, '@'
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beq t0, t1, .Ltoken_character_single
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(* Expect an identifier or a number. *)
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.Ltoken_character_loop_do
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lw t6, 4(sp)
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add t1, s1, t6
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lbu a0, (t1) # a0 = Current character.
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call _is_alnum
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beqz a0, .Ltoken_character_end
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loca4 := loca4 + 1
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goto .Ltoken_character_loop_do
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.Ltoken_character_single
|
|
loca4 := loca4 + 1
|
|
goto .Ltoken_character_end
|
|
|
|
.Ltoken_character_colon
|
|
lbu t0, 1(s1) # t0 = The character after the colon.
|
|
loca4 := loca4 + 1
|
|
|
|
li t1, '='
|
|
beq t0, t1, .Ltoken_character_single
|
|
goto .Ltoken_character_end
|
|
|
|
.Ltoken_character_end
|
|
lw a0, 4(sp)
|
|
end
|
|
|
|
(* Skips the spaces till the next non space character. *)
|
|
proc _skip_spaces()
|
|
begin
|
|
.Lspace_loop_do
|
|
lbu t0, (s1) # t0 = Current character.
|
|
|
|
li t1, ' '
|
|
beq t0, t1, .Lspace_loop_repeat
|
|
li t1, '\t'
|
|
beq t0, t1, .Lspace_loop_repeat
|
|
li t1, '\n'
|
|
beq t0, t1, .Lspace_loop_repeat
|
|
li t1, '\r'
|
|
beq t0, t1, .Lspace_loop_repeat
|
|
|
|
goto .Lspace_loop_end
|
|
.Lspace_loop_repeat
|
|
_advance(1)
|
|
goto .Lspace_loop_do
|
|
|
|
.Lspace_loop_end
|
|
end
|
|
|
|
(* Skips tabs at the line beginning. *)
|
|
proc _skip_indentation()
|
|
begin
|
|
.Lskip_indentation_do
|
|
lbu t0, (s1)
|
|
|
|
li t1, '\t'
|
|
beq t0, t1, .Lskip_indentation_skip
|
|
|
|
goto .Lskip_indentation_end
|
|
|
|
.Lskip_indentation_skip
|
|
_advance(1)
|
|
goto .Lskip_indentation_do
|
|
|
|
.Lskip_indentation_end
|
|
end
|
|
|
|
(*
|
|
Parameters:
|
|
a0 - Line length.
|
|
*)
|
|
proc _skip_comment(loca84: Word)
|
|
begin
|
|
(* Check whether this is a comment. *)
|
|
li t0, 0x2a28 # (*
|
|
sw t0, 4(sp)
|
|
addi a0, sp, 4
|
|
mv a1, s1
|
|
li a2, 2
|
|
call _memcmp
|
|
bnez a0, .Lskip_comment_end
|
|
|
|
_advance(2) (* Skip (*. *)
|
|
|
|
li t0, 0x292a # *)
|
|
sw t0, 4(sp)
|
|
|
|
.Lskip_comment_loop
|
|
addi a0, sp, 4
|
|
mv a1, s1
|
|
li a2, 2
|
|
call _memcmp
|
|
beqz a0, .Lskip_comment_close
|
|
|
|
_advance(1)
|
|
|
|
goto .Lskip_comment_loop
|
|
|
|
.Lskip_comment_close
|
|
_advance(2) (* Skip "*" and ")". *)
|
|
|
|
.Lskip_comment_end
|
|
end
|
|
|
|
(*
|
|
Parameters:
|
|
a0 - Line length.
|
|
*)
|
|
proc _compile_assembly(loca84: Word)
|
|
var loca0: ^Byte
|
|
begin
|
|
(* Write the source to the standard output. *)
|
|
loca0 := _current()
|
|
|
|
_write_out(loca0, loca84)
|
|
_advance(loca84)
|
|
|
|
_put_char(0xa) (* \n *)
|
|
|
|
_advance(1) (* Skip the new line. *)
|
|
end
|
|
|
|
proc _compile_program()
|
|
var loca0: Word
|
|
begin
|
|
(* .global _start *)
|
|
loca0 := 0x6f6c672e (* .glo *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x206c6162 (* bal_ *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x6174735f (* _sta *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a7472 (* rt\n *)
|
|
_write_out(@loca0, 3)
|
|
|
|
_advance(8) (* program\n. *)
|
|
end
|
|
|
|
proc _compile_constant_section()
|
|
var loca0: Word
|
|
begin
|
|
(* .section .rodata *)
|
|
loca0 := 0x6365732e (* .sec *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x6e6f6974 (* tion *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x6f722e20 (* _.ro *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x61746164 (* data *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a (* \n *)
|
|
_write_out(@loca0, 1)
|
|
|
|
_advance(6) (* const\n. *)
|
|
|
|
.Lcompile_constant_section_item
|
|
_skip_spaces()
|
|
lbu a0, (s1)
|
|
call _is_upper
|
|
beqz a0, .Lcompile_constant_section_end
|
|
|
|
_compile_constant()
|
|
goto .Lcompile_constant_section_item
|
|
|
|
.Lcompile_constant_section_end
|
|
end
|
|
|
|
proc _compile_constant()
|
|
var
|
|
loca0, loca4: Word
|
|
loca8: ^Byte
|
|
begin
|
|
loca4 := _read_token()
|
|
loca8 := _current() (* Save the identifier pointer before advancing it. *)
|
|
|
|
_write_out(loca8, loca4)
|
|
_advance(loca4)
|
|
|
|
_skip_spaces()
|
|
_advance(2) (* Skip the assignment sign. *)
|
|
|
|
(* : .long *)
|
|
loca0 := 0x6c2e203a (* : .l *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x20676e6f (* ong_ *)
|
|
_write_out(@loca0, 4)
|
|
|
|
_skip_spaces()
|
|
loca4 := _read_token()
|
|
loca8 := _current() (* Save the literal pointer before advancing it. *)
|
|
|
|
_write_out(loca8, loca4)
|
|
_advance(loca4)
|
|
|
|
_put_char(0x0a) (* \n *)
|
|
end
|
|
|
|
proc _compile_variable_section()
|
|
var loca0: Word
|
|
begin
|
|
(* .section .bss *)
|
|
loca0 := 0x6365732e (* .sec *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x6e6f6974 (* tion *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x73622e20 (* _.bs *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a73 (* s\n *)
|
|
_write_out(@loca0, 2)
|
|
|
|
_advance(4) (* var\n. *)
|
|
|
|
.Lcompile_variable_section_item
|
|
_skip_spaces()
|
|
lbu a0, (s1)
|
|
call _is_lower
|
|
beqz a0, .Lcompile_variable_section_end
|
|
|
|
_compile_variable()
|
|
goto .Lcompile_variable_section_item
|
|
|
|
.Lcompile_variable_section_end
|
|
end
|
|
|
|
proc _compile_variable()
|
|
var
|
|
loca28, loca16: ^Byte
|
|
loca0, loca24, loca20: Word
|
|
begin
|
|
(* Save the identifier on the stack since it should emitted multiple times. *)
|
|
loca24 := _read_token()
|
|
loca28 := _current()
|
|
|
|
_advance(loca24)
|
|
|
|
_skip_spaces()
|
|
_advance(1) (* Skip the colon in front of the type. *)
|
|
|
|
_skip_spaces()
|
|
_advance(1) (* Skip the opening bracket. *)
|
|
|
|
(* Save the array size on the stack since it has to be emitted multiple times. *)
|
|
loca16 := _read_token()
|
|
loca20 := _current()
|
|
_advance(loca16)
|
|
|
|
_skip_spaces()
|
|
_advance(1) (* Skip the closing bracket. *)
|
|
|
|
_skip_spaces()
|
|
loca0 := _read_token()
|
|
_advance(loca0) (* Skip the type. *)
|
|
|
|
(* .type identifier, @object *)
|
|
loca0 := 0x7079742e (* .typ *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x2065 (* e_ *)
|
|
_write_out(@loca0, 2)
|
|
|
|
_write_out(loca28, loca24)
|
|
|
|
loca0 := 0x6f40202c (* , @o *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x63656a62 (* bjec *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a74 (* t\n *)
|
|
_write_out(@loca0, 2)
|
|
|
|
(* .size identifier, size *)
|
|
loca0 := 0x7a69732e (* .siz *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x2065 (* e_ *)
|
|
_write_out(@loca0, 2)
|
|
|
|
_write_out(loca28, loca24)
|
|
|
|
loca0 := 0x202c (* ,_ *)
|
|
_write_out(@loca0, 2)
|
|
|
|
_write_out(loca20, loca16)
|
|
_put_char(0x0a) (* \n *)
|
|
|
|
(* identifier: .zero size *)
|
|
_write_out(loca28, loca24)
|
|
|
|
loca0 := 0x7a2e203a (* : .z *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x206f7265 (* ero_ *)
|
|
_write_out(@loca0, 4)
|
|
|
|
_write_out(loca20, loca16)
|
|
|
|
_put_char(0x0a) (* \n *)
|
|
end
|
|
|
|
proc _compile_procedure()
|
|
var
|
|
loca0, loca4, loca8, loca12, loca16: Word
|
|
loca20: ^Char
|
|
begin
|
|
_advance(5) (* Skip proc_ *)
|
|
loca16 := _read_token()
|
|
loca20 := _current()
|
|
_advance(loca16)
|
|
|
|
(* .type identifier, @function *)
|
|
loca0 := 0x7079742e (* .typ *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x2065 (* e_ *)
|
|
_write_out(@loca0, 2)
|
|
|
|
_write_out(loca20, loca16)
|
|
|
|
loca0 := 0x6640202c (* , @f *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x74636e75 (* unct *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a6e6f69 (* ion\n *)
|
|
_write_out(@loca0, 4)
|
|
|
|
_write_out(loca20, loca16)
|
|
|
|
loca0 := 0x0a3a (* :\n *)
|
|
_write_out(@loca0, 2)
|
|
|
|
_skip_spaces()
|
|
_advance(1) (* Skip opening argument paren. *)
|
|
_skip_spaces()
|
|
_advance(1) (* Skip closing argument paren. *)
|
|
|
|
loca12 := 0x6e (* n *)
|
|
loca8 := 0x69676562 (* begi *)
|
|
|
|
(*
|
|
Skip all declarations until we find the "begin" keyword, denoting the
|
|
beginning of the procedure body.
|
|
*)
|
|
.Lcompile_procedure_begin
|
|
_skip_spaces()
|
|
call _read_token
|
|
|
|
mv a1, a0
|
|
mv a0, s1
|
|
addi a2, sp, 8
|
|
add s1, s1, a1
|
|
call _token_compare
|
|
|
|
bnez a0, .Lcompile_procedure_begin
|
|
|
|
(* Generate the procedure prologue with a predefined stack size. *)
|
|
loca0 := 0x69646461 (* addi *)
|
|
_write_out(@loca0, 4)
|
|
|
|
loca0 := 0x2c707320 (* _sp, *)
|
|
_write_out(@loca0, 4)
|
|
_write_out(@loca0, 4)
|
|
|
|
loca0 := 0x0a36392d (* -96\n *)
|
|
_write_out(@loca0, 4)
|
|
|
|
loca0 := 0x72207773 (* sw r *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x39202c61 (* a, 9 *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x70732832 (* 2(sp *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a29 (* )\n *)
|
|
_write_out(@loca0, 2)
|
|
|
|
loca0 := 0x73207773 (* sw s *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x38202c30 (* 0, 8 *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x70732838 (* 8(sp *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a29 (* )\n *)
|
|
_write_out(@loca0, 2)
|
|
|
|
loca0 := 0x69646461 (* addi *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x2c307320 (* _s0, *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x2c707320 (* _sp, *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a363920 (* _96\n *)
|
|
_write_out(@loca0, 4)
|
|
|
|
(* Save passed arguments on the stack. *)
|
|
loca0 := 0x61207773 (* sw a *)
|
|
_write_out(@loca0, 4)
|
|
loca4 := 0x38202c30 (* 0, 8 *)
|
|
_write_out(@loca4, 4)
|
|
loca8 := 0x70732834 (* 4(sp *)
|
|
_write_out(@loca8, 4)
|
|
loca12 := 0x0a29 (* )\n *)
|
|
_write_out(@loca12, 2)
|
|
|
|
_write_out(@loca0, 4)
|
|
loca4 := 0x38202c31 (* 1, 8 *)
|
|
_write_out(@loca4, 4)
|
|
loca8 := 0x70732830 (* 0(sp *)
|
|
_write_out(@loca8, 4)
|
|
_write_out(@loca12, 2)
|
|
|
|
_write_out(@loca0, 4)
|
|
loca4 := 0x37202c32 (* 2, 7 *)
|
|
_write_out(@loca4, 4)
|
|
loca8 := 0x70732836 (* 6(sp *)
|
|
_write_out(@loca8, 4)
|
|
_write_out(@loca12, 2)
|
|
|
|
_write_out(@loca0, 4)
|
|
loca4 := 0x37202c33 (* 3, 7 *)
|
|
_write_out(@loca4, 4)
|
|
loca8 := 0x70732832 (* 2(sp *)
|
|
_write_out(@loca8, 4)
|
|
_write_out(@loca12, 2)
|
|
|
|
_write_out(@loca0, 4)
|
|
loca4 := 0x36202c34 (* 4, 6 *)
|
|
_write_out(@loca4, 4)
|
|
loca8 := 0x70732838 (* 8(sp *)
|
|
_write_out(@loca8, 4)
|
|
_write_out(@loca12, 2)
|
|
|
|
_write_out(@loca0, 4)
|
|
loca4 := 0x36202c35 (* 5, 6 *)
|
|
_write_out(@loca4, 4)
|
|
loca8 := 0x70732838 (* 4(sp *)
|
|
_write_out(@loca8, 4)
|
|
_write_out(@loca12, 2)
|
|
|
|
(* Generate the body of the procedure. *)
|
|
.Lcompile_procedure_body
|
|
_skip_indentation()
|
|
call _read_line
|
|
sw a0, 12(sp)
|
|
li t0, 0x0a646e65 # end\n
|
|
sw t0, 8(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 8
|
|
li a2, 4
|
|
call _memcmp
|
|
|
|
beqz a0, .Lcompile_procedure_end
|
|
|
|
lw a0, 12(sp)
|
|
call _compile_line
|
|
goto .Lcompile_procedure_body
|
|
|
|
.Lcompile_procedure_end
|
|
_advance(4) (* Skip end\n. *)
|
|
|
|
(* Generate the procedure epilogue with a predefined stack size. *)
|
|
loca0 := 0x7220776c # lw r
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x39202c61 # a, 9
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x70732832 # 2(sp
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a29 # )\n
|
|
_write_out(@loca0, 2)
|
|
|
|
loca0 := 0x7320776c (* lw s *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x38202c30 (* 0, 8 *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x70732838 (* 8(sp *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a29 (* )\n *)
|
|
_write_out(@loca0, 2)
|
|
|
|
loca0 := 0x69646461 (* addi *)
|
|
_write_out(@loca0, 4)
|
|
|
|
loca0 := 0x2c707320 (* _sp, *)
|
|
_write_out(@loca0, 4)
|
|
_write_out(@loca0, 4)
|
|
|
|
loca0 := 0x0a3639 (* 96\n *)
|
|
_write_out(@loca0, 4)
|
|
|
|
loca0 := 0x0a746572 (* ret\n *)
|
|
_write_out(@loca0, 4)
|
|
end
|
|
|
|
(*
|
|
Compares two string, which of one has a length, the other one is null-terminated.
|
|
|
|
a0 - The address of the token string.
|
|
a1 - The length of the string in a0.
|
|
a2 - The address of the null-terminated string.
|
|
|
|
If the strings match sets a0 to 0, otherwise sets it to 1.
|
|
*)
|
|
proc _token_compare()
|
|
begin
|
|
addi t0, a0, 0
|
|
addi t1, a1, 0
|
|
addi t2, a2, 0
|
|
|
|
.Ltoken_compare_loop
|
|
lbu t3, (t2)
|
|
|
|
(*
|
|
Will only be 0 if the current character in the null terminated string is \0 and the remaining length of the
|
|
another string is 0.
|
|
*)
|
|
or t4, t3, t1
|
|
beqz t4, .Ltoken_compare_equal
|
|
|
|
beqz t1, .Ltoken_compare_not_equal
|
|
beqz t3, .Ltoken_compare_not_equal
|
|
|
|
lbu t4, (t0)
|
|
bne t3, t4, .Ltoken_compare_not_equal
|
|
|
|
addi t0, t0, 1
|
|
addi t1, t1, -1
|
|
addi t2, t2, 1
|
|
goto .Ltoken_compare_loop
|
|
|
|
.Ltoken_compare_not_equal
|
|
li a0, 1
|
|
goto .Ltoken_compare_end
|
|
|
|
.Ltoken_compare_equal
|
|
li a0, 0
|
|
|
|
.Ltoken_compare_end
|
|
end
|
|
|
|
proc _compile_goto()
|
|
var
|
|
loca0: Word
|
|
loca8: ^Byte
|
|
begin
|
|
_advance(4) (* Skip the goto keyword. *)
|
|
|
|
loca0 := 0x206a (* j_ *)
|
|
_write_out(@loca0, 2)
|
|
|
|
_skip_spaces()
|
|
loca8 := _current() (* We should be on dot the label is beginning with. *)
|
|
_advance(1)
|
|
|
|
loca0 := _read_token()
|
|
_advance(loca0)
|
|
loca0 := loca0 + 1 (* Label length and the dot. *)
|
|
_write_out(loca8, loca0)
|
|
|
|
_advance(1) (* Skip the new line. *)
|
|
_put_char(0x0a) (* \n *)
|
|
end
|
|
|
|
(* a0 - Line length. *)
|
|
proc _compile_label(loca84: Word)
|
|
var
|
|
loca0: Word
|
|
begin
|
|
(* Write the whole line as is. *)
|
|
loca0 := _current()
|
|
_write_out(loca0, loca84)
|
|
|
|
lw t0, 84(sp) # Line length.
|
|
mv t1, s1 # Line start.
|
|
|
|
add t1, t1, t0
|
|
addi t1, t1, -1 # Last character on the line.
|
|
|
|
lbu t1, (t1)
|
|
li t2, ':'
|
|
beq t1, t2, .Lcompile_label_colon
|
|
|
|
_put_char(0x3a) (* : *)
|
|
|
|
.Lcompile_label_colon
|
|
_put_char(0x0a) (* \n *)
|
|
|
|
_advance(loca84)
|
|
end
|
|
|
|
proc _compile_return()
|
|
begin
|
|
_advance(6) (* Skip return. *)
|
|
_skip_spaces()
|
|
_build_binary_expression()
|
|
end
|
|
|
|
(*
|
|
Parameters:
|
|
a0 - Line length.
|
|
a1 - Whether the section header was already emitted. If not it should be
|
|
emitted before any code is written.
|
|
|
|
Returns 1 in a0 if the parsed line contained a text section element such a
|
|
procedure or the program entry point. Otherwise sets a0 to 0.
|
|
*)
|
|
proc _compile_line(loca84: Word, loca80: Bool)
|
|
begin
|
|
beqz a0, .Lcompile_line_empty # Skip an empty line.
|
|
|
|
lbu t0, (s1)
|
|
li t1, '('
|
|
beq t0, t1, .Lcompile_line_comment
|
|
|
|
li t0, 0x0a6d6172 # ram\n
|
|
sw t0, 12(sp)
|
|
li t0, 0x676f7270 # prog
|
|
sw t0, 8(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 8
|
|
li a2, 8
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_program
|
|
|
|
li t0, 0x0a74 # t\n
|
|
sw t0, 12(sp)
|
|
li t0, 0x736e6f63 # cons
|
|
sw t0, 8(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 8
|
|
li a2, 6
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_const
|
|
|
|
li t0, 0x0a726176 # var\n
|
|
sw t0, 12(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 12
|
|
li a2, 4
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_var
|
|
|
|
li t0, 0x20 # _
|
|
sw t0, 12(sp)
|
|
li t0, 0x636f7270 # proc
|
|
sw t0, 8(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 8
|
|
li a2, 5
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_procedure
|
|
|
|
li t0, 0x0a6e # n\n
|
|
sw t0, 12(sp)
|
|
li t0, 0x69676562 # begi
|
|
sw t0, 8(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 8
|
|
li a2, 6
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_begin
|
|
|
|
li t0, 0x2e646e65 # end.
|
|
sw t0, 12(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 12
|
|
li a2, 4
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_exit
|
|
|
|
li t0, 0x61636f6c # loca
|
|
sw t0, 12(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 12
|
|
li a2, 4
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_identifier
|
|
|
|
li t0, 0x7472 # rt
|
|
sw t0, 12(sp)
|
|
li t0, 0x6f706d69 # impo
|
|
sw t0, 8(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 8
|
|
li a2, 6
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_import
|
|
|
|
li t0, 0x6f746f67 # goto
|
|
sw t0, 12(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 12
|
|
li a2, 4
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_goto
|
|
|
|
li t0, 0x6e72 # rn
|
|
sw t0, 12(sp)
|
|
li t0, 0x75746572 # retu
|
|
sw t0, 8(sp)
|
|
mv a0, s1
|
|
addi a1, sp, 8
|
|
li a2, 6
|
|
call _memcmp
|
|
beqz a0, .Lcompile_line_return
|
|
|
|
lbu t0, (s1)
|
|
li t1, '.'
|
|
beq t0, t1, .Lcompile_line_label
|
|
li t1, '_'
|
|
beq t0, t1, .Lcompile_line_identifier
|
|
|
|
goto .Lcompile_line_unchanged (* Else. *)
|
|
|
|
.Lcompile_line_label
|
|
_compile_label(loca84)
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_return
|
|
(* DEBUG
|
|
mv a0, s1
|
|
li a1, 8
|
|
call _write_error *)
|
|
_compile_return()
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_goto
|
|
_compile_goto()
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_import
|
|
_compile_import()
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_identifier
|
|
_compile_identifier()
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_exit
|
|
_compile_exit()
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_begin
|
|
lw a1, 80(sp)
|
|
bnez a1, .Lcompile_line_compile_entry
|
|
_compile_text_section()
|
|
.Lcompile_line_compile_entry
|
|
_compile_entry_point()
|
|
li a0, 1
|
|
goto .Lcompile_line_end
|
|
|
|
.Lcompile_line_const
|
|
_compile_constant_section()
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_procedure
|
|
lw a1, 80(sp)
|
|
bnez a1, .Lcompile_line_compile_procedure
|
|
_compile_text_section()
|
|
.Lcompile_line_compile_procedure
|
|
_compile_procedure()
|
|
li a0, 1
|
|
goto .Lcompile_line_end
|
|
|
|
.Lcompile_line_var
|
|
_compile_variable_section()
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_program
|
|
_compile_program()
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_comment
|
|
_skip_comment(loca84)
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_empty
|
|
_advance(1)
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_unchanged
|
|
_compile_assembly(loca84)
|
|
goto .Lcompile_line_section
|
|
|
|
.Lcompile_line_section
|
|
mv a0, zero
|
|
|
|
.Lcompile_line_end
|
|
sw a0, 12(sp)
|
|
_skip_spaces()
|
|
_skip_comment()
|
|
lw a0, 12(sp)
|
|
end
|
|
|
|
(* Prints ".section .text" and exits. *)
|
|
proc _compile_text_section()
|
|
var loca0: Word
|
|
begin
|
|
(* .section .text *)
|
|
loca0 := 0x6365732e (* .sec *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x6e6f6974 (* tion *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x65742e20 (* _.te *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a7478 (* xt\n *)
|
|
_write_out(@loca0, 3)
|
|
end
|
|
|
|
proc _compile_entry_point()
|
|
var loca0: Word
|
|
begin
|
|
(* .type _start, @function *)
|
|
loca0 := 0x7079742e (* .typ *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x735f2065 (* e _s *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x74726174 (* tart *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x6640202c (* , @f *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x74636e75 (* unct *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a6e6f69 (* ion\n *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x6174735f (* _sta *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a3a7472 (* rt:\n *)
|
|
_write_out(@loca0, 4)
|
|
|
|
_advance(6) (* Skip begin\n. *)
|
|
end
|
|
|
|
proc _compile_exit()
|
|
var loca0: Word
|
|
begin
|
|
(*
|
|
li a0, 0
|
|
li a7, SYS_EXIT
|
|
ecall
|
|
*)
|
|
loca0 := 0x6120696c (* li a *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x30202c30 (* 0, 0 *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x20696c0a (* \nli_ *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x202c3761 (* a7,_ *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x650a3339 (* 93\ne *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x6c6c6163 (* call *)
|
|
_write_out(@loca0, 4)
|
|
loca0 := 0x0a (* \n *)
|
|
_write_out(@loca0, 1)
|
|
|
|
_advance(4) (* Skip end. *)
|
|
_skip_spaces() (* Read the possible new line at the end of the file. *)
|
|
end
|
|
|
|
(* Finds the end of the line and returns its length in a0. *)
|
|
proc _read_line()
|
|
begin
|
|
loca0 := _current() (* Local position in the source text. *)
|
|
|
|
.Lread_line_do
|
|
lw t0, 0(sp)
|
|
lbu t1, (t0) # t1 = Current character.
|
|
beqz t1, .Lread_line_end # Exit the loop on the NUL character.
|
|
li t2, '\n'
|
|
beq t1, t2, .Lread_line_end # Exit the loop on the new line.
|
|
|
|
loca0 := loca0 + 1
|
|
goto .Lread_line_do
|
|
|
|
.Lread_line_end
|
|
loca4 := _current()
|
|
return loca0 - loca4 (* Return the line length. *)
|
|
end
|
|
|
|
proc _compile()
|
|
var loca0, loca4: Word
|
|
begin
|
|
loca4 := 0 (* Whether the text section header was already emitted. *)
|
|
|
|
.Lcompile_do
|
|
lbu t0, (s1) # t0 = Current character.
|
|
beqz t0, .Lcompile_end # Exit the loop on the NUL character.
|
|
|
|
_skip_indentation()
|
|
loca0 := _read_line()
|
|
lw a0, 0(sp)
|
|
lw a1, 4(sp)
|
|
call _compile_line
|
|
|
|
beqz a0, .Lcompile_do
|
|
(* Update whether the text section header was already emitted. *)
|
|
lw t0, 4(sp)
|
|
or t0, t0, a0
|
|
sw t0, 4(sp)
|
|
|
|
goto .Lcompile_do
|
|
.Lcompile_end
|
|
end
|
|
|
|
(* Returns the pointer to the current position in the source text in a0. *)
|
|
proc _current()
|
|
begin
|
|
mv a0, s1
|
|
end
|
|
|
|
(* a0 is the number of bytes to advance in the source text. *)
|
|
proc _advance()
|
|
begin
|
|
add s1, s1, a0
|
|
end
|
|
|
|
(* Returns the first character in the remaining source text. *)
|
|
proc _front()
|
|
begin
|
|
lbu a0, (s1)
|
|
end
|
|
|
|
(* Entry point. *)
|
|
begin
|
|
(* Read the source from the standard input. *)
|
|
la a0, source_code
|
|
la a1, SOURCE_BUFFER_SIZE # Buffer size.
|
|
lw a1, (a1)
|
|
call _read_file
|
|
|
|
la s1, source_code # s1 = Source code position.
|
|
_compile()
|
|
end.
|