diff options
| -rw-r--r-- | Rakefile | 47 | ||||
| -rw-r--r-- | boot/stage8.elna | 694 | ||||
| -rw-r--r-- | boot/stage9.elna | 1179 |
3 files changed, 1405 insertions, 515 deletions
@@ -14,7 +14,7 @@ directory 'build/boot' directory 'build/valid' def compile(input, output) - sh ENV.fetch('CC', 'gcc'), '-nostdlib', '-o', output, input + sh ENV.fetch('CC', 'gcc'), '-nostdlib', '-fpie', '-g', '-o', output, input end def run(exe) @@ -39,43 +39,16 @@ end desc 'Convert previous stage language into the current stage language' task :convert do - File.open('boot/stage8.elna', 'w') do |current_stage| - File.readlines('boot/stage7.elna').each do |line| - if line == ".section .bss\n" - current_stage << <<~SECTION - const - symbol_builtin_name_int := "Int"; - symbol_builtin_name_word := "Word"; - symbol_builtin_name_pointer := "Pointer"; - symbol_builtin_name_char := "Char"; - symbol_builtin_name_bool := "Bool"; - - # Every type info starts with a word describing what type it is. - # - # PRIMITIVE_TYPE = 1 - # - # Primitive types have only type size. - symbol_builtin_type_int := S(1, 4); - symbol_builtin_type_word := S(1, 4); - symbol_builtin_type_pointer := S(1, 4); - symbol_builtin_type_char := S(1, 1); - symbol_builtin_type_bool := S(1, 1); - - # Info objects start with a word describing its type. - # - # INFO_TYPE = 1 - # - # Type info has the type it belongs to. - symbol_type_info_int := S(1, @symbol_builtin_type_int); - symbol_type_info_word := S(1, @symbol_builtin_type_word); - symbol_type_info_pointer := S(1, @symbol_builtin_type_pointer); - symbol_type_info_char := S(1, @symbol_builtin_type_char); - symbol_type_info_bool := S(1, @symbol_builtin_type_bool); - SECTION - elsif line == ".section .data\n" - current_stage << "var\n" - elsif !(line == ".section .text\n" || line == ".globl _start\n") + File.open('boot/stage9.elna', 'w') do |current_stage| + File.readlines('boot/stage8.elna').each do |line| + comment_match = /^(\s*)#(.*)/.match line + + if comment_match.nil? current_stage << line + elsif comment_match[2].empty? + current_stage << "\n" + else + current_stage << "#{comment_match[1]}(* #{comment_match[2].strip} *)\n" end end end diff --git a/boot/stage8.elna b/boot/stage8.elna index c88e19d..6243634 100644 --- a/boot/stage8.elna +++ b/boot/stage8.elna @@ -4,7 +4,9 @@ # Stage 8 compiler. # - +# - Procedure calls in expressions. +# - Comments between (* and *) are supported. These are still single line +# comments and they should be on a separate line. const symbol_builtin_name_int := "Int"; symbol_builtin_name_word := "Word"; @@ -34,14 +36,13 @@ const symbol_type_info_char := S(1, @symbol_builtin_type_char); symbol_type_info_bool := S(1, @symbol_builtin_type_bool); -# When modifiying also change the read size in the entry point procedure. -.type source_code, @object -source_code: .zero 81920 - -.type compiler_strings, @object -compiler_strings: .zero 8192 - var + source_code: Array; + compiler_strings: Array; + symbol_table_global: Array; + symbol_table_local: Array; + classification: Array; + compiler_strings_position: Pointer := @compiler_strings; compiler_strings_length: Word := 0; source_code_position: Pointer := @source_code; @@ -130,7 +131,8 @@ begin mv a1, a0 # STDIN. li a0, 0 - li a7, 63 # SYS_READ. + # SYS_READ. + li a7, 63 ecall end; @@ -145,7 +147,8 @@ begin mv a1, a0 # STDOUT. li a0, 1 - li a7, 64 # SYS_WRITE. + # SYS_WRITE. + li a7, 64 ecall end; @@ -323,7 +326,8 @@ begin .read_token_loop: lw t0, 0(sp) - lb t0, (t0) # Current character. + # Current character. + lb t0, (t0) # First we try to read a derictive. # A derictive can contain a dot and characters. @@ -425,44 +429,6 @@ begin return v88 end; -proc _compile_section(); -begin - # Print and skip the ".section" (8 characters) directive and a space after it. - _write_token(9); - _advance_token(); - - # Read the section name. - _read_token(); - addi a0, a0, 1 - - _write_token(); - _advance_token(); -end; - -# Prints and skips a line. -proc _skip_comment(); -begin - la t0, source_code_position - lw t1, (t0) - -.skip_comment_loop: - # Check for newline character. - lb t2, (t1) - li t3, '\n' - beq t2, t3, .skip_comment_end - - # Advance the input string by one byte. - addi t1, t1, 1 - sw t1, (t0) - - goto .skip_comment_loop; - -.skip_comment_end: - # Skip the newline. - addi t1, t1, 1 - sw t1, (t0) -end; - # Prints and skips a line. proc _compile_line(); begin @@ -601,6 +567,9 @@ begin li t1, '"' beq a0, t1, .compile_term_string_literal + li t1, '_' + beq a0, t1, .compile_term_call + _is_digit(v0); bnez a0, .compile_term_integer_literal @@ -630,6 +599,11 @@ begin _compile_string_literal(); goto .compile_term_end; +.compile_term_call: + _compile_call(); + _write_z("\nmv t0, a0\n\0"); + goto .compile_term_end; + .compile_term_variable: _compile_variable_expression(); goto .compile_term_end; @@ -1038,6 +1012,8 @@ end; proc _compile_procedure_body(); begin .compile_procedure_body_loop: + _skip_empty_lines(); + # 3 is "end" length. _memcmp(source_code_position, "end", 3); @@ -1091,7 +1067,8 @@ begin _advance_token(5); _read_token(); - sw a0, 0(sp) # Save the procedure name length. + # Save the procedure name length. + sw a0, 0(sp) # Write .type _procedure_name, @function. _write_z(".type \0"); @@ -1136,13 +1113,41 @@ begin .skip_newlines_end: end; +# Prints and skips a line. +proc _skip_comment(); +begin + la t0, source_code_position + lw t1, (t0) + +.skip_comment_loop: + # Check for newline character. + lb t2, (t1) + li t3, '\n' + beq t2, t3, .skip_comment_end + + # Advance the input string by one byte. + addi t1, t1, 1 + sw t1, (t0) + + goto .skip_comment_loop; + +.skip_comment_end: + # Skip the newline. + addi t1, t1, 1 + sw t1, (t0) +end; + # Skip newlines and comments. proc _skip_empty_lines(); begin -.skip_empty_lines_loop: +.skip_empty_lines_rerun: la t0, source_code_position lw t0, (t0) - lb t0, (t0) + sw t0, 0(sp) + +.skip_empty_lines_loop: + lw t2, 0(sp) + lb t0, (t2) li t1, '#' beq t0, t1, .skip_empty_lines_comment @@ -1150,15 +1155,35 @@ begin li t1, '\n' beq t0, t1, .skip_empty_lines_newline + li t1, '\t' + beq t0, t1, .skip_empty_lines_tab + + li t1, '(' + bne t0, t1, .skip_empty_lines_end + addi t2, t2, 1 + lb t0, (t2) + li t1, '*' + beq t0, t1, .skip_empty_lines_comment + goto .skip_empty_lines_end; .skip_empty_lines_comment: + la t0, source_code_position + lw t1, 0(sp) + sw t1, (t0) _skip_comment(); - goto .skip_empty_lines_loop; + goto .skip_empty_lines_rerun; .skip_empty_lines_newline: - _advance_token(1); - goto .skip_empty_lines_loop; + la t0, source_code_position + lw t1, 0(sp) + addi t1, t1, 1 + sw t1, (t0) + goto .skip_empty_lines_rerun; + +.skip_empty_lines_tab: + v0 := v0 + 1; + goto .skip_empty_lines_loop .skip_empty_lines_end: end; @@ -1295,12 +1320,6 @@ begin _advance_token(1); - la t0, source_code_position - lw t0, (t0) - lb t0, (t0) - li t1, '#' - beq t0, t1, .compile_const_part_loop - _compile_constant_declaration(); goto .compile_const_part_loop; @@ -1358,18 +1377,16 @@ begin _write_z(".section .data\n\0"); .compile_var_part_loop: + _skip_empty_lines(); + la t0, source_code_position lw t0, (t0) lb t0, (t0) - li t1, 'p' - beq t0, t1, .compile_var_part_end - li t1, '\t' beq t0, t1, .compile_var_part_declaration - _compile_line(); - goto .compile_var_part_loop; + goto .compile_var_part_end; .compile_var_part_declaration: _advance_token(1); @@ -1383,64 +1400,25 @@ end; proc _compile_module(); begin _compile_const_part(); - _write_z(".section .bss\n\0"); - -.compile_module_bss: - la t0, source_code_position - lw t0, (t0) - lb t0, (t0) - li t1, 'v' - beq t0, t1, .compile_module_code - - li t1, 'p' - beq t0, t1, .compile_module_code - - _compile_line(); - goto .compile_module_bss; - -.compile_module_code: + _skip_empty_lines(); _compile_var_part(); + _write_z(".section .text\n\0"); .compile_module_loop: - _skip_newlines(); + _skip_empty_lines(); la t0, source_code_position lw t0, (t0) lb t0, (t0) beqz t0, .compile_module_end - li t1, '#' - beq t0, t1, .compile_module_comment - - # 8 is ".section" length. - _memcmp(source_code_position, ".section", 8); - beqz a0, .compile_module_section # 5 is "proc " length. Space is needed to distinguish from "procedure". _memcmp(source_code_position, "proc ", 5); beqz a0, .compile_module_procedure - # 6 is ".globl" length. - _memcmp(source_code_position, ".globl", 6); - beqz a0, .compile_module_global - # Not a known token, exit. goto .compile_module_end; -.compile_module_section: - _compile_section(); - - goto .compile_module_loop; - -.compile_module_global: - _compile_line(); - - goto .compile_module_loop; - -.compile_module_comment: - _skip_comment(); - - goto .compile_module_loop; - .compile_module_procedure: _compile_procedure(); @@ -1490,14 +1468,512 @@ begin ecall end; +# Inserts a symbol into the table. +# +# Parameters: +# a0 - Symbol pointer. +# a1 - Symbol name length. +# a2 - Symbol name pointer. +# a3 - Symbol table. +proc _symbol_table_enter(); +begin + # The first word in the symbol table is its length, get it. + lw a0, 76(sp) + lw a0, (a0) + sw a0, 0(sp) + + # Calculate the offset for the new symbol. + v4 := v0 * 4; + v4 := v4 + 4; + v4 := v76 + 4; + + _memcpy(v4, @v80, 12); + + # Increment the symbol table length. + v0 := v0 + 1; + lw t0, 0(sp) + lw t1, 76(sp) + sw t0, (t1) +end; + +proc _symbol_table_build(); +begin + _symbol_table_enter(@symbol_type_info_int, 3, symbol_builtin_name_int, @symbol_table_global); + _symbol_table_enter(@symbol_type_info_word, 4, symbol_builtin_name_word, @symbol_table_global); + _symbol_table_enter(@symbol_type_info_pointer, 7, symbol_builtin_name_pointer, @symbol_table_global); + _symbol_table_enter(@symbol_type_info_char, 4, symbol_builtin_name_char, @symbol_table_global); + _symbol_table_enter(@symbol_type_info_bool, 4, symbol_builtin_name_bool, @symbol_table_global); +end; + +# +# Classification table assigns each possible character to a group (class). All +# characters of the same group a handled equivalently. +# +# Classification: +# +# TransitionClass = ( +# transitionClassInvalid = 1, +# transitionClassDigit = 2, +# transitionClassAlpha = 3, +# transitionClassSpace = 4, +# transitionClassColon = 5, +# transitionClassEquals = 6, +# transitionClassLeftParen = 7, +# transitionClassRightParen = 8, +# transitionClassAsterisk = 9, +# transitionClassUnderscore = 10, +# transitionClassSingle = 11, +# transitionClassHex = 12, +# transitionClassZero = 13, +# transitionClassX = 14, +# transitionClassEof = 15, +# transitionClassDot = 16, +# transitionClassMinus = 17, +# transitionClassSingleQuote = 18, +# transitionClassDoubleQuote = 19, +# transitionClassGreater = 20, +# transitionClassLess = 21, +# transitionClassOther = 22 +# ); +# TransitionState = ( +# transitionStateStart = 1, +# transitionStateColon = 2, +# transitionStateIdentifier = 3, +# transitionStateDecimal = 4, +# transitionStateGreater = 5, +# transitionStateMinus = 6, +# transitionStateLeftParen = 7, +# transitionStateLess = 8, +# transitionStateDot = 9, +# transitionStateComment = 10, +# transitionStateClosingComment = 11, +# transitionStateCharacter = 12, +# transitionStateString = 13, +# transitionStateLeadingZero = 14, +# transitionStateDecimalSuffix = 15, +# transitionStateEnd = 16 +# ); +# Transition = record +# action: TransitionAction; +# next_state: TransitionState +# end; +# TransitionAction = ( +# none = 1, +# accumulate = 2, +# skip = 3, +# single = 4, +# eof = 5, +# finalize = 6, +# composite = 7, +# key_id = 8, +# integer = 9, +# delimited = 10 +# ); + +# Assigns some value to at array index. +# +# Parameters: +# a0 - Array pointer. +# a1 - Index (word offset into the array). +# a2 - Data to assign. +proc _assign_at(); +begin + v0 := v84 + -1; + v0 := v0 * 4; + v0 := v88 + v0; + + lw t0, 0(sp) + lw t1, 80(sp) + sw t1, (t0) +end; + +proc _initialize_classification(); +begin + _assign_at(@classification, 1, 15); + _assign_at(@classification, 2, 1); + _assign_at(@classification, 3, 1); + _assign_at(@classification, 4, 1); + _assign_at(@classification, 5, 1); + _assign_at(@classification, 6, 1); + _assign_at(@classification, 7, 1); + _assign_at(@classification, 8, 1); + _assign_at(@classification, 9, 1); + _assign_at(@classification, 10, 4); + _assign_at(@classification, 11, 4); + _assign_at(@classification, 12, 1); + _assign_at(@classification, 13, 1); + _assign_at(@classification, 14, 4); + _assign_at(@classification, 15, 1); + _assign_at(@classification, 16, 1); + _assign_at(@classification, 17, 1); + _assign_at(@classification, 18, 1); + _assign_at(@classification, 19, 1); + _assign_at(@classification, 20, 1); + _assign_at(@classification, 21, 1); + _assign_at(@classification, 22, 1); + _assign_at(@classification, 23, 1); + _assign_at(@classification, 24, 1); + _assign_at(@classification, 25, 1); + _assign_at(@classification, 26, 1); + _assign_at(@classification, 27, 1); + _assign_at(@classification, 28, 1); + _assign_at(@classification, 29, 1); + _assign_at(@classification, 30, 1); + _assign_at(@classification, 31, 1); + _assign_at(@classification, 32, 1); + _assign_at(@classification, 33, 4); + _assign_at(@classification, 34, 11); + _assign_at(@classification, 35, 19); + _assign_at(@classification, 36, 22); + _assign_at(@classification, 37, 22); + _assign_at(@classification, 38, 11); + _assign_at(@classification, 39, 11); + _assign_at(@classification, 40, 18); + _assign_at(@classification, 41, 7); + _assign_at(@classification, 42, 8); + _assign_at(@classification, 43, 9); + _assign_at(@classification, 44, 11); + _assign_at(@classification, 45, 11); + _assign_at(@classification, 46, 17); + _assign_at(@classification, 47, 16); + _assign_at(@classification, 48, 11); + _assign_at(@classification, 49, 13); + _assign_at(@classification, 50, 2); + _assign_at(@classification, 51, 2); + _assign_at(@classification, 52, 2); + _assign_at(@classification, 53, 2); + _assign_at(@classification, 54, 2); + _assign_at(@classification, 55, 2); + _assign_at(@classification, 56, 2); + _assign_at(@classification, 57, 2); + _assign_at(@classification, 58, 2); + _assign_at(@classification, 59, 5); + _assign_at(@classification, 60, 11); + _assign_at(@classification, 61, 21); + _assign_at(@classification, 62, 6); + _assign_at(@classification, 63, 20); + _assign_at(@classification, 64, 22); + _assign_at(@classification, 65, 11); + _assign_at(@classification, 66, 3); + _assign_at(@classification, 67, 3); + _assign_at(@classification, 68, 3); + _assign_at(@classification, 69, 3); + _assign_at(@classification, 70, 3); + _assign_at(@classification, 71, 3); + _assign_at(@classification, 72, 3); + _assign_at(@classification, 73, 3); + _assign_at(@classification, 74, 3); + _assign_at(@classification, 75, 3); + _assign_at(@classification, 76, 3); + _assign_at(@classification, 77, 3); + _assign_at(@classification, 78, 3); + _assign_at(@classification, 79, 3); + _assign_at(@classification, 80, 3); + _assign_at(@classification, 81, 3); + _assign_at(@classification, 82, 3); + _assign_at(@classification, 83, 3); + _assign_at(@classification, 84, 3); + _assign_at(@classification, 85, 3); + _assign_at(@classification, 86, 3); + _assign_at(@classification, 87, 3); + _assign_at(@classification, 88, 3); + _assign_at(@classification, 89, 3); + _assign_at(@classification, 90, 3); + _assign_at(@classification, 91, 3); + _assign_at(@classification, 92, 11); + _assign_at(@classification, 93, 22); + _assign_at(@classification, 94, 11); + _assign_at(@classification, 95, 11); + _assign_at(@classification, 96, 10); + _assign_at(@classification, 97, 22); + _assign_at(@classification, 98, 12); + _assign_at(@classification, 99, 12); + _assign_at(@classification, 100, 12); + _assign_at(@classification, 101, 12); + _assign_at(@classification, 102, 12); + _assign_at(@classification, 103, 12); + _assign_at(@classification, 104, 3); + _assign_at(@classification, 105, 3); + _assign_at(@classification, 106, 3); + _assign_at(@classification, 107, 3); + _assign_at(@classification, 108, 3); + _assign_at(@classification, 109, 3); + _assign_at(@classification, 110, 3); + _assign_at(@classification, 111, 3); + _assign_at(@classification, 112, 3); + _assign_at(@classification, 113, 3); + _assign_at(@classification, 114, 3); + _assign_at(@classification, 115, 3); + _assign_at(@classification, 116, 3); + _assign_at(@classification, 117, 3); + _assign_at(@classification, 118, 3); + _assign_at(@classification, 119, 3); + _assign_at(@classification, 120, 3); + _assign_at(@classification, 121, 14); + _assign_at(@classification, 122, 3); + _assign_at(@classification, 123, 3); + _assign_at(@classification, 124, 22); + _assign_at(@classification, 125, 11); + _assign_at(@classification, 126, 22); + _assign_at(@classification, 127, 11); + _assign_at(@classification, 128, 1); + + v0 := 129; + +# Set the remaining 129 - 256 bytes to transitionClassOther. +.initialize_classification_loop: + _assign_at(@classification, v0, 22); + v0 := v0 + 1; + + lw t0, 0(sp) + li t1, 257 + blt t0, t1, .initialize_classification_loop +end; + +# Parameters: +# a0 - Current state (first index into transitions table). +# a1 - Transition (second index into transitions table).. +# a2 - Action to assign. +# a3 - Next state to assign. +proc _set_transition(); +begin + # Transitions start at offset in classification array. Save the transitions start in v0. + la t0, classification + addi t0, t0, 256 + sw t0, 0(sp) + + # Each state is 8 bytes long (2 words: action and next state). + # There are 16 transition classes, so a transition 8 * 16 = 128 bytes long. + + v4 := v88 + -1; + v4 := v4 * 128; + + v8 := v84 + -1; + v8 := v8 * 8; + + v12 := v0 + v4; + v12 := v12 + v8; + + lw t0, 12(sp) + lw t1, 80(sp) + lw t2, 76(sp) + sw t1, (t0) + addi t0, t0, 4 + sw t2, (t0) +end; + +# Parameters: +# a0 - Current state (Transition state enumeration). +# a1 - Default action (Callback). +# a2 - Next state (Transition state enumeration). +proc _set_default_transition(); +begin + _set_transition(v88, 1, v84, v80); + _set_transition(v88, 2, v84, v80); + _set_transition(v88, 3, v84, v80); + _set_transition(v88, 4, v84, v80); + _set_transition(v88, 5, v84, v80); + _set_transition(v88, 6, v84, v80); + _set_transition(v88, 7, v84, v80); + _set_transition(v88, 8, v84, v80); + _set_transition(v88, 9, v84, v80); + _set_transition(v88, 10, v84, v80); + _set_transition(v88, 11, v84, v80); + _set_transition(v88, 12, v84, v80); + _set_transition(v88, 13, v84, v80); + _set_transition(v88, 14, v84, v80); + _set_transition(v88, 15, v84, v80); + _set_transition(v88, 16, v84, v80); + _set_transition(v88, 17, v84, v80); + _set_transition(v88, 18, v84, v80); + _set_transition(v88, 19, v84, v80); + _set_transition(v88, 20, v84, v80); + _set_transition(v88, 21, v84, v80); + _set_transition(v88, 22, v84, v80); +end; + + +# The transition table describes transitions from one state to another, given +# a symbol (character class). +# +# The table has m rows and n columns, where m is the amount of states and n is +# the amount of classes. So given the current state and a classified character +# the table can be used to look up the next state. +# +# Each cell is a word long. +# - The least significant byte of the word is a row number (beginning with 0). +# It specifies the target state. "ff" means that this is an end state and no +# transition is possible. +# - The next byte is the action that should be performed when transitioning. +# For the meaning of actions see labels in the lex_next function, which +# handles each action. +proc _initialize_transitions(); +begin + # Start state. + _set_transition(1, 1, 1, 16); + _set_transition(1, 2, 2, 4); + _set_transition(1, 3, 2, 3); + _set_transition(1, 4, 3, 1); + _set_transition(1, 5, 2, 5); + _set_transition(1, 6, 4, 16); + _set_transition(1, 7, 2, 7); + _set_transition(1, 8, 4, 16); + _set_transition(1, 9, 4, 16); + _set_transition(1, 10, 2, 3); + _set_transition(1, 11, 4, 16); + _set_transition(1, 12, 2, 3); + _set_transition(1, 13, 2, 14); + _set_transition(1, 14, 2, 3); + _set_transition(1, 15, 5, 16); + _set_transition(1, 16, 2, 9); + _set_transition(1, 17, 2, 6); + _set_transition(1, 18, 2, 12); + _set_transition(1, 19, 2, 13); + _set_transition(1, 20, 2, 5); + _set_transition(1, 21, 2, 8); + _set_transition(1, 22, 1, 16); + + # Colon state. + _set_default_transition(2, 6, 16); + _set_transition(2, 6, 7, 16); + + # Identifier state. + _set_default_transition(3, 8, 16); + _set_transition(3, 2, 2, 3); + _set_transition(3, 3, 2, 3); + _set_transition(3, 10, 2, 3); + _set_transition(3, 12, 2, 3); + _set_transition(3, 13, 2, 3); + _set_transition(3, 14, 2, 3); + + # Decimal state. + _set_default_transition(4, 9, 16); + _set_transition(4, 2, 2, 4); + _set_transition(4, 3, 2, 15); + _set_transition(4, 10, 1, 16); + _set_transition(4, 12, 2, 15); + _set_transition(4, 13, 2, 4); + _set_transition(4, 14, 2, 15); + + # Greater state. + _set_default_transition(5, 6, 16); + _set_transition(5, 6, 7, 16); + + # Minus state. + _set_default_transition(6, 6, 16); + _set_transition(6, 20, 7, 16); + + # Left paren state. + _set_default_transition(7, 6, 16); + _set_transition(7, 9, 2, 10); + + # Less state. + _set_default_transition(8, 6, 16); + _set_transition(8, 6, 7, 16); + _set_transition(8, 20, 7, 16); + + # Hexadecimal after 0x. + _set_default_transition(9, 6, 16); + _set_transition(9, 16, 7, 16); + + # Comment. + _set_default_transition(10, 2, 10); + _set_transition(10, 9, 2, 11); + _set_transition(10, 15, 1, 16); + + # Closing comment. + _set_default_transition(11, 2, 10); + _set_transition(11, 1, 1, 16); + _set_transition(11, 8, 10, 16); + _set_transition(11, 9, 2, 11); + _set_transition(11, 15, 1, 16); + + # Character. + _set_default_transition(12, 2, 12); + _set_transition(12, 1, 1, 16); + _set_transition(12, 15, 1, 16); + _set_transition(12, 18, 10, 16); + + # String. + _set_default_transition(13, 2, 13); + _set_transition(13, 1, 1, 16); + _set_transition(13, 15, 1, 16); + _set_transition(13, 19, 10, 16); + + # Leading zero. + _set_default_transition(14, 9, 16); + _set_transition(14, 2, 1, 16); + _set_transition(14, 3, 1, 16); + _set_transition(14, 10, 1, 16); + _set_transition(14, 12, 1, 16); + _set_transition(14, 13, 1, 16); + _set_transition(14, 14, 1, 16); + + # Digit with a character suffix. + _set_default_transition(15, 9, 16); + _set_transition(15, 3, 1, 16); + _set_transition(15, 2, 1, 16); + _set_transition(15, 12, 1, 16); + _set_transition(15, 13, 1, 16); + _set_transition(15, 14, 1, 16); +end; + +proc _lexer_get_state(); +begin + # Lexer state is saved after the transition tables. The offset is 256 + 16 * 22. + v0 := @classification; + v4 := 16 * 22; + v0 := v0 + 256; + + return v0 + v4 +end; + +# Gets pointer to the current source text. +proc _lexer_get_current(); +begin + _lexer_get_state(); + sw a0, 0(sp) + + return v0 + 4 +end; + +# Resets the lexer state for reading the next token. +proc _lexer_reset(); +begin + # Transition start state is 1. + _lexer_get_state(); + li t0, 1 + sw t0, (a0) + sw a0, 0(sp) + + # Text pointer to the beginning of the currently read token. + _lexer_get_current(); + la t0, source_code_position + lw t0, (t0) + sw t0, (a0) + + # Initial length of the token is 0. + addi t0, t0, 4 + sw zero, (t0) +end; + +# One time lexer initialization. +proc _lexer_initialize(); +begin + _initialize_classification(); + _initialize_transitions(); +end; + # Entry point. proc _start(); begin + _lexer_initialize(); + _symbol_table_build(); + # Read the source from the standard input. # Second argument is buffer size. Modifying update the source_code definition. _read_file(@source_code, 81920); _compile(); _exit(0); - end; diff --git a/boot/stage9.elna b/boot/stage9.elna index f429b10..ebeb467 100644 --- a/boot/stage9.elna +++ b/boot/stage9.elna @@ -1,10 +1,12 @@ -# This Source Code Form is subject to the terms of the Mozilla Public License, -# v. 2.0. If a copy of the MPL was not distributed with this file, You can -# obtain one at https://mozilla.org/MPL/2.0/. +(* This Source Code Form is subject to the terms of the Mozilla Public License, *) +(* v. 2.0. If a copy of the MPL was not distributed with this file, You can *) +(* obtain one at https://mozilla.org/MPL/2.0/. *) -# Stage 9 compiler. -# +(* Stage 8 compiler. *) +(* - Procedure calls in expressions. *) +(* - Comments between (* and *) are supported. These are still single line *) +(* comments and they should be on a separate line. *) const symbol_builtin_name_int := "Int"; symbol_builtin_name_word := "Word"; @@ -12,50 +14,49 @@ const symbol_builtin_name_char := "Char"; symbol_builtin_name_bool := "Bool"; - # Every type info starts with a word describing what type it is. - # - # PRIMITIVE_TYPE = 1 - # - # Primitive types have only type size. + (* Every type info starts with a word describing what type it is. *) + + (* PRIMITIVE_TYPE = 1 *) + + (* Primitive types have only type size. *) symbol_builtin_type_int := S(1, 4); symbol_builtin_type_word := S(1, 4); symbol_builtin_type_pointer := S(1, 4); symbol_builtin_type_char := S(1, 1); symbol_builtin_type_bool := S(1, 1); - # Info objects start with a word describing its type. - # - # INFO_TYPE = 1 - # - # Type info has the type it belongs to. + (* Info objects start with a word describing its type. *) + + (* INFO_TYPE = 1 *) + + (* Type info has the type it belongs to. *) symbol_type_info_int := S(1, @symbol_builtin_type_int); symbol_type_info_word := S(1, @symbol_builtin_type_word); symbol_type_info_pointer := S(1, @symbol_builtin_type_pointer); symbol_type_info_char := S(1, @symbol_builtin_type_char); symbol_type_info_bool := S(1, @symbol_builtin_type_bool); -# When modifiying also change the read size in the entry point procedure. -.type source_code, @object -source_code: .zero 81920 - -.type compiler_strings, @object -compiler_strings: .zero 8192 - var + source_code: Array; + compiler_strings: Array; + symbol_table_global: Array; + symbol_table_local: Array; + classification: Array; + compiler_strings_position: Pointer := @compiler_strings; compiler_strings_length: Word := 0; source_code_position: Pointer := @source_code; -# Calculates and returns the string token length between quotes, including the -# escaping slash characters. -# -# Parameters: -# a0 - String token pointer. -# -# Returns the length in a0. +(* Calculates and returns the string token length between quotes, including the *) +(* escaping slash characters. *) + +(* Parameters: *) +(* a0 - String token pointer. *) + +(* Returns the length in a0. *) proc _string_length(); begin - # Reset the counter. + (* Reset the counter. *) v0 := 0; .string_length_loop: @@ -74,12 +75,12 @@ begin return v0 end; -# Adds a string to the global, read-only string storage. -# -# Parameters: -# a0 - String token. -# -# Returns the offset from the beginning of the storage to the new string in a0. +(* Adds a string to the global, read-only string storage. *) + +(* Parameters: *) +(* a0 - String token. *) + +(* Returns the offset from the beginning of the storage to the new string in a0. *) proc _add_string(); begin v0 := v88 + 1; @@ -119,48 +120,50 @@ begin return v4 end; -# Reads standard input into a buffer. -# a0 - Buffer pointer. -# a1 - Buffer size. -# -# Returns the amount of bytes written in a0. +(* Reads standard input into a buffer. *) +(* a0 - Buffer pointer. *) +(* a1 - Buffer size. *) + +(* Returns the amount of bytes written in a0. *) proc _read_file(); begin mv a2, a1 mv a1, a0 - # STDIN. + (* STDIN. *) li a0, 0 - li a7, 63 # SYS_READ. + (* SYS_READ. *) + li a7, 63 ecall end; -# Writes to the standard output. -# -# Parameters: -# a0 - Buffer. -# a1 - Buffer length. +(* Writes to the standard output. *) + +(* Parameters: *) +(* a0 - Buffer. *) +(* a1 - Buffer length. *) proc _write_s(); begin mv a2, a1 mv a1, a0 - # STDOUT. + (* STDOUT. *) li a0, 1 - li a7, 64 # SYS_WRITE. + (* SYS_WRITE. *) + li a7, 64 ecall end; -# Writes a number to a string buffer. -# -# t0 - Local buffer. -# t1 - Constant 10. -# t2 - Current character. -# t3 - Whether the number is negative. -# -# Parameters: -# a0 - Whole number. -# a1 - Buffer pointer. -# -# Sets a0 to the length of the written number. +(* Writes a number to a string buffer. *) + +(* t0 - Local buffer. *) +(* t1 - Constant 10. *) +(* t2 - Current character. *) +(* t3 - Whether the number is negative. *) + +(* Parameters: *) +(* a0 - Whole number. *) +(* a1 - Buffer pointer. *) + +(* Sets a0 to the length of the written number. *) proc _print_i(); begin li t1, 10 @@ -196,42 +199,38 @@ begin return v0 end; -# Writes a number to the standard output. -# -# Parameters: -# a0 - Whole number. +(* Writes a number to the standard output. *) + +(* Parameters: *) +(* a0 - Whole number. *) proc _write_i(); begin - _print_i(v88, @v0); - - mv a1, a0 - addi a0, sp, 0 - _write_s(); - + v4 := _print_i(v88, @v0); + _write_s(@v0, v4); end; -# Writes a character from a0 into the standard output. +(* Writes a character from a0 into the standard output. *) proc _write_c(); begin _write_s(@v88, 1); end; -# Write null terminated string. -# -# Parameters: -# a0 - String. +(* Write null terminated string. *) + +(* Parameters: *) +(* a0 - String. *) proc _write_z(); begin .write_z_loop: - # Check for 0 character. + (* Check for 0 character. *) lw a0, 88(sp) lb a0, (a0) beqz a0, .write_z_end - # Print a character. + (* Print a character. *) _write_c(); - # Advance the input string by one byte. + (* Advance the input string by one byte. *) v88 := v88 + 1; goto .write_z_loop; @@ -239,7 +238,7 @@ begin .write_z_end: end; -# Detects if a0 is an uppercase character. Sets a0 to 1 if so, otherwise to 0. +(* Detects if a0 is an uppercase character. Sets a0 to 1 if so, otherwise to 0. *) proc _is_upper(); begin v0 := v88 >= 'A'; @@ -249,7 +248,7 @@ begin end; -# Detects if a0 is an lowercase character. Sets a0 to 1 if so, otherwise to 0. +(* Detects if a0 is an lowercase character. Sets a0 to 1 if so, otherwise to 0. *) proc _is_lower(); begin v0 := v88 >= 'a'; @@ -259,37 +258,29 @@ begin end; -# Detects if the passed character is a 7-bit alpha character or an underscore. -# -# Paramters: -# a0 - Tested character. -# -# Sets a0 to 1 if the character is an alpha character or underscore, sets it to 0 otherwise. +(* Detects if the passed character is a 7-bit alpha character or an underscore. *) + +(* Paramters: *) +(* a0 - Tested character. *) + +(* Sets a0 to 1 if the character is an alpha character or underscore, sets it to 0 otherwise. *) proc _is_alpha(); begin - sw a0, 0(sp) + v0 := _is_upper(v88); + v4 := _is_lower(v88); + v8 := v88 = '_'; - _is_upper(); - sw a0, 4(sp) - - _is_lower(v0); + v12 := v0 or v4; + return v12 or v8 +end; - lw t0, 0(sp) - xori t1, t0, '_' - seqz t1, t1 +(* Detects whether the passed character is a digit *) +(* (a value between 0 and 9). *) - lw t0, 4(sp) - or a0, a0, t0 - or a0, a0, t1 -end; +(* Parameters: *) +(* a0 - Exemined value. *) -# Detects whether the passed character is a digit -# (a value between 0 and 9). -# -# Parameters: -# a0 - Exemined value. -# -# Sets a0 to 1 if it is a digit, to 0 otherwise. +(* Sets a0 to 1 if it is a digit, to 0 otherwise. *) proc _is_digit(); begin v0 := v88 >= '0'; @@ -300,33 +291,29 @@ end; proc _is_alnum(); begin - sw a0, 4(sp) + v0 := _is_alpha(v88); + v4 := _is_digit(v88); - _is_alpha(); - sw a0, 0(sp) - - _is_digit(v4); - - lw a1, 0(sp) - or a0, a0, a1 + return v0 or v4 end; -# Reads the next token. -# -# Returns token length in a0. +(* Reads the next token. *) + +(* Returns token length in a0. *) proc _read_token(); begin - # Current token position. + (* Current token position. *) v0 := source_code_position; - # Token length. + (* Token length. *) v4 := 0; .read_token_loop: lw t0, 0(sp) - lb t0, (t0) # Current character. + (* Current character. *) + lb t0, (t0) - # First we try to read a derictive. - # A derictive can contain a dot and characters. + (* First we try to read a derictive. *) + (* A derictive can contain a dot and characters. *) li t1, '.' beq t0, t1, .read_token_next @@ -338,7 +325,7 @@ begin goto .read_token_end; .read_token_next: - # Advance the source code position and token length. + (* Advance the source code position and token length. *) v4 := v4 + 1; v0 := v0 + 1; @@ -348,11 +335,11 @@ begin return v4 end; -# a0 - First pointer. -# a1 - Second pointer. -# a2 - The length to compare. -# -# Returns 0 in a0 if memory regions are equal. +(* a0 - First pointer. *) +(* a1 - Second pointer. *) +(* a2 - The length to compare. *) + +(* Returns 0 in a0 if memory regions are equal. *) proc _memcmp(); begin mv t0, a0 @@ -376,18 +363,16 @@ begin .memcmp_end: end; -# Copies memory. -# -# Parameters: -# a0 - Destination. -# a1 - Source. -# a2 - Size. -# -# Preserves a0. +(* Copies memory. *) + +(* Parameters: *) +(* a0 - Destination. *) +(* a1 - Source. *) +(* a2 - Size. *) + +(* Preserves a0. *) proc _memcpy(); begin - mv t0, a0 - .memcpy_loop: beqz a2, .memcpy_end @@ -401,10 +386,10 @@ begin goto .memcpy_loop .memcpy_end: - mv a0, t0 + return v88 end; -# Advances the token stream by a0 bytes. +(* Advances the token stream by a0 bytes. *) proc _advance_token(); begin la t0, source_code_position @@ -413,57 +398,19 @@ begin sw t1, (t0) end; -# Prints the current token. -# -# Parameters: -# a0 - Token length. -# -# Returns a0 unchanged. +(* Prints the current token. *) + +(* Parameters: *) +(* a0 - Token length. *) + +(* Returns a0 unchanged. *) proc _write_token(); begin _write_s(source_code_position, v88); return v88 end; -proc _compile_section(); -begin - # Print and skip the ".section" (8 characters) directive and a space after it. - _write_token(9); - _advance_token(); - - # Read the section name. - _read_token(); - addi a0, a0, 1 - - _write_token(); - _advance_token(); -end; - -# Prints and skips a line. -proc _skip_comment(); -begin - la t0, source_code_position - lw t1, (t0) - -.skip_comment_loop: - # Check for newline character. - lb t2, (t1) - li t3, '\n' - beq t2, t3, .skip_comment_end - - # Advance the input string by one byte. - addi t1, t1, 1 - sw t1, (t0) - - goto .skip_comment_loop; - -.skip_comment_end: - # Skip the newline. - addi t1, t1, 1 - sw t1, (t0) -end; - -# Prints and skips a line. +(* Prints and skips a line. *) proc _compile_line(); begin .compile_line_loop: @@ -474,11 +421,11 @@ begin li t1, '\n' beq t0, t1, .compile_line_end - # Print a character. + (* Print a character. *) lw a0, (a1) _write_c(); - # Advance the input string by one byte. + (* Advance the input string by one byte. *) _advance_token(1); goto .compile_line_loop; @@ -493,9 +440,9 @@ proc _compile_integer_literal(); begin _write_z("\tli t0, \0"); - _read_token(); - _write_token(); - _advance_token(); + v0 := _read_token(); + _write_token(v0); + _advance_token(v0); _write_c('\n'); end; @@ -526,7 +473,6 @@ begin _write_c('\n'); _advance_token(2); - end; proc _compile_variable_expression(); @@ -537,15 +483,14 @@ end; proc _compile_address_expression(); begin - # Skip the "@" sign. + (* Skip the "@" sign. *) _advance_token(1); _compile_designator(); - end; proc _compile_negate_expression(); begin - # Skip the "-" sign. + (* Skip the "-" sign. *) _advance_token(1); _compile_term(); @@ -554,7 +499,7 @@ end; proc _compile_not_expression(); begin - # Skip the "~" sign. + (* Skip the "~" sign. *) _advance_token(1); _compile_term(); @@ -563,11 +508,8 @@ end; proc _compile_string_literal(); begin - _string_length(source_code_position); - sw a0, 0(sp) - - _add_string(source_code_position); - sw a0, 4(sp) + v0 := _string_length(source_code_position); + v4 := _add_string(source_code_position); _advance_token(v0 + 2); _write_z("\tla t0, strings\n\0"); @@ -601,6 +543,9 @@ begin li t1, '"' beq a0, t1, .compile_term_string_literal + li t1, '_' + beq a0, t1, .compile_term_call + _is_digit(v0); bnez a0, .compile_term_integer_literal @@ -630,6 +575,11 @@ begin _compile_string_literal(); goto .compile_term_end; +.compile_term_call: + _compile_call(); + _write_z("\nmv t0, a0\n\0"); + goto .compile_term_end; + .compile_term_variable: _compile_variable_expression(); goto .compile_term_end; @@ -639,11 +589,11 @@ end; proc _compile_binary_rhs(); begin - # Skip the whitespace after the binary operator. + (* Skip the whitespace after the binary operator. *) _advance_token(1); _compile_term(); - # Load the left expression from the stack; + (* Load the left expression from the stack; *) _write_z("\tlw t1, 24(sp)\n\0"); end; @@ -658,12 +608,12 @@ begin li t1, ' ' bne a0, t1, .compile_expression_end - # It is a binary expression. + (* It is a binary expression. *) - # Save the value of the left expression on the stack. + (* Save the value of the left expression on the stack. *) _write_z("sw t0, 24(sp)\n\0"); - # Skip surrounding whitespace in front of the operator. + (* Skip surrounding whitespace in front of the operator. *) _advance_token(1); la t0, source_code_position lw t0, (t0) @@ -693,14 +643,14 @@ begin li t1, '>' beq t0, t1, .compile_expression_greater - # Unknown binary operator. + (* Unknown binary operator. *) unimp .compile_expression_add: _advance_token(1); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("add t0, t0, t1\n\0"); goto .compile_expression_end; @@ -709,7 +659,7 @@ begin _advance_token(1); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("\tmul t0, t0, t1\n\0"); goto .compile_expression_end; @@ -718,7 +668,7 @@ begin _advance_token(1); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("\tand t0, t0, t1\n\0"); goto .compile_expression_end; @@ -727,7 +677,7 @@ begin _advance_token(2); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("or t0, t0, t1\n\0"); goto .compile_expression_end; @@ -736,7 +686,7 @@ begin _advance_token(3); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("xor t0, t0, t1\n\0"); goto .compile_expression_end; @@ -745,7 +695,7 @@ begin _advance_token(1); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("xor t0, t0, t1\nseqz t0, t0\n\0"); goto .compile_expression_end; @@ -764,7 +714,7 @@ begin _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("slt t0, t0, t1\n\0"); goto .compile_expression_end; @@ -773,7 +723,7 @@ begin _advance_token(1); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("\txor t0, t0, t1\nsnez t0, t0\n\0"); goto .compile_expression_end; @@ -782,7 +732,7 @@ begin _advance_token(1); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("\tslt t0, t0, t1\nxori t0, t0, 1\n\0"); goto .compile_expression_end; @@ -798,7 +748,7 @@ begin _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("\tslt t0, t1, t0\n\0"); goto .compile_expression_end; @@ -807,7 +757,7 @@ begin _advance_token(1); _compile_binary_rhs(); - # Execute the operation. + (* Execute the operation. *) _write_z("\tslt t0, t1, t0\nxori t0, t0, 1\n\0"); goto .compile_expression_end; @@ -817,17 +767,16 @@ end; proc _compile_call(); begin - # Stack variables: - # v0 - Procedure name length. - # v4 - Procedure name pointer. - # v8 - Argument count. + (* Stack variables: *) + (* v0 - Procedure name length. *) + (* v4 - Procedure name pointer. *) + (* v8 - Argument count. *) - _read_token(); - sw a0, 0(sp) + v0 := _read_token(); v4 := source_code_position; v8 := 0; - # Skip the identifier and left paren. + (* Skip the identifier and left paren. *) _advance_token(v0 + 1); la t0, source_code_position @@ -840,17 +789,17 @@ begin .compile_call_loop: _compile_expression(); - # Save the argument on the stack. + (* Save the argument on the stack. *) _write_z("\tsw t0, \0"); - # Calculate the stack offset: 116 - (4 * argument_counter) + (* Calculate the stack offset: 116 - (4 * argument_counter) *) v12 := v8 * 4; v12 := 116 + -v12; _write_i(v12); _write_z("(sp)\n\0"); - # Add one to the argument counter. + (* Add one to the argument counter. *) v8 := v8 + 1; la t0, source_code_position @@ -864,12 +813,12 @@ begin goto .compile_call_loop; .compile_call_finalize: - # Load the argument from the stack. + (* Load the argument from the stack. *) lw t0, 8(sp) beqz t0, .compile_call_end - # Decrement the argument counter. + (* Decrement the argument counter. *) v8 := v8 + -1; _write_z("\tlw a\0"); @@ -877,7 +826,7 @@ begin _write_z(", \0"); - # Calculate the stack offset: 116 - (4 * argument_counter) + (* Calculate the stack offset: 116 - (4 * argument_counter) *) v12 := v8 * 4; v12 := 116 + -v12; _write_i(v12); @@ -890,7 +839,7 @@ begin _write_z("\tcall \0"); _write_s(v4, v0); - # Skip the right paren. + (* Skip the right paren. *) _advance_token(1); end; @@ -898,9 +847,7 @@ proc _compile_goto(); begin _advance_token(5); - _read_token(); - sw a0, 0(sp) - + v0 := _read_token(); _write_z("\tj \0"); _write_token(v0); @@ -909,14 +856,14 @@ end; proc _compile_local_designator(); begin - # Skip "v" in the local variable name. + (* Skip "v" in the local variable name. *) _advance_token(1); _write_z("\t addi t0, sp, \0"); - # Read local variable stack offset and save it. - _read_token(); - _write_token(); - _advance_token(); + (* Read local variable stack offset and save it. *) + v0 := _read_token(); + _write_token(v0); + _advance_token(v0); _write_c('\n'); end; @@ -924,9 +871,9 @@ proc _compile_global_designator(); begin _write_z("\tla t0, \0"); - _read_token(); - _write_token(); - _advance_token(); + v0 := _read_token(); + _write_token(v0); + _advance_token(v0); _write_c('\n'); end; @@ -957,13 +904,13 @@ proc _compile_assignment(); begin _compile_designator(); - # Save the assignee address on the stack. + (* Save the assignee address on the stack. *) _write_z("\tsw t0, 20(sp)\n\0"); - # Skip the assignment sign (:=) with surrounding whitespaces. + (* Skip the assignment sign (:=) with surrounding whitespaces. *) _advance_token(4); - # Compile the assignment. + (* Compile the assignment. *) _compile_expression(); _write_z("\tlw t1, 20(sp)\nsw t0, (t1)\n\0"); @@ -971,7 +918,7 @@ end; proc _compile_return_statement(); begin - # Skip "return" keyword and whitespace after it. + (* Skip "return" keyword and whitespace after it. *) _advance_token(7); _compile_expression(); @@ -980,10 +927,10 @@ end; proc _compile_statement(); begin - # This is a call if the statement starts with an underscore. + (* This is a call if the statement starts with an underscore. *) la t0, source_code_position lw t0, (t0) - # First character after alignment tab. + (* First character after alignment tab. *) addi t0, t0, 1 lb t0, (t0) @@ -996,7 +943,7 @@ begin li t1, 'v' beq t0, t1, .compile_statement_assignment - # keyword_ret contains "\tret", so it's 4 bytes long. + (* keyword_ret contains "\tret", so it's 4 bytes long. *) _memcmp(source_code_position, "\treturn", 7); beqz a0, .compile_statement_return @@ -1038,7 +985,9 @@ end; proc _compile_procedure_body(); begin .compile_procedure_body_loop: - # 3 is "end" length. + _skip_empty_lines(); + + (* 3 is "end" length. *) _memcmp(source_code_position, "end", 3); beqz a0, .compile_procedure_body_epilogue @@ -1049,11 +998,11 @@ begin .compile_procedure_body_epilogue: end; -# Writes a regster name to the standard output. -# -# Parameters: -# a0 - Register character. -# a1 - Register number. +(* Writes a regster name to the standard output. *) + +(* Parameters: *) +(* a0 - Register character. *) +(* a1 - Register number. *) proc _write_register(); begin _write_c(v88); @@ -1071,7 +1020,7 @@ begin _write_i(v0); _write_z(", \0"); - # Calculate the stack offset: 88 - (4 * parameter_counter) + (* Calculate the stack offset: 88 - (4 * parameter_counter) *) v4 := v0 * 4; v4 := 88 + -v4; _write_i(v4); @@ -1087,38 +1036,38 @@ end; proc _compile_procedure(); begin - # Skip "proc ". + (* Skip "proc ". *) _advance_token(5); - _read_token(); - sw a0, 0(sp) # Save the procedure name length. + (* Save the procedure name length. *) + v0 := _read_token(); - # Write .type _procedure_name, @function. + (* Write .type _procedure_name, @function. *) _write_z(".type \0"); _write_token(v0); _write_z(", @function\n\0"); - # Write procedure label, _procedure_name: + (* Write procedure label, _procedure_name: *) _write_token(v0); _write_z(":\n\0"); - # Skip the function name and trailing parens, semicolon, "begin" and newline. + (* Skip the function name and trailing parens, semicolon, "begin" and newline. *) _advance_token(v0 + 10); _compile_procedure_prologue(); _compile_procedure_body(); - # Write the epilogue. + (* Write the epilogue. *) _write_z("\tlw ra, 124(sp)\n\tlw s0, 120(sp)\n\taddi sp, sp, 128\n\tret\n\0"); - # Skip the "end" keyword, semicolon and newline. + (* Skip the "end" keyword, semicolon and newline. *) _advance_token(5); end; proc _skip_newlines(); begin - # Skip newlines. + (* Skip newlines. *) la t0, source_code_position lw t1, (t0) @@ -1136,13 +1085,41 @@ begin .skip_newlines_end: end; -# Skip newlines and comments. +(* Prints and skips a line. *) +proc _skip_comment(); +begin + la t0, source_code_position + lw t1, (t0) + +.skip_comment_loop: + (* Check for newline character. *) + lb t2, (t1) + li t3, '\n' + beq t2, t3, .skip_comment_end + + (* Advance the input string by one byte. *) + addi t1, t1, 1 + sw t1, (t0) + + goto .skip_comment_loop; + +.skip_comment_end: + (* Skip the newline. *) + addi t1, t1, 1 + sw t1, (t0) +end; + +(* Skip newlines and comments. *) proc _skip_empty_lines(); begin -.skip_empty_lines_loop: +.skip_empty_lines_rerun: la t0, source_code_position lw t0, (t0) - lb t0, (t0) + sw t0, 0(sp) + +.skip_empty_lines_loop: + lw t2, 0(sp) + lb t0, (t2) li t1, '#' beq t0, t1, .skip_empty_lines_comment @@ -1150,15 +1127,35 @@ begin li t1, '\n' beq t0, t1, .skip_empty_lines_newline + li t1, '\t' + beq t0, t1, .skip_empty_lines_tab + + li t1, '(' + bne t0, t1, .skip_empty_lines_end + addi t2, t2, 1 + lb t0, (t2) + li t1, '*' + beq t0, t1, .skip_empty_lines_comment + goto .skip_empty_lines_end; .skip_empty_lines_comment: + la t0, source_code_position + lw t1, 0(sp) + sw t1, (t0) _skip_comment(); - goto .skip_empty_lines_loop; + goto .skip_empty_lines_rerun; .skip_empty_lines_newline: - _advance_token(1); - goto .skip_empty_lines_loop; + la t0, source_code_position + lw t1, 0(sp) + addi t1, t1, 1 + sw t1, (t0) + goto .skip_empty_lines_rerun; + +.skip_empty_lines_tab: + v0 := v0 + 1; + goto .skip_empty_lines_loop .skip_empty_lines_end: end; @@ -1187,25 +1184,25 @@ begin unimp .compile_global_initializer_pointer: - # Skip @. + (* Skip @. *) _advance_token(1); _write_z("\n\t.word \0"); - _read_token(); - _write_token(); - _advance_token(); + v0 := _read_token(); + _write_token(v0); + _advance_token(v0); goto .compile_global_initializer_end; .compile_global_initializer_number: _write_z("\n\t.word \0"); - _read_token(); - _write_token(); + v0 := _read_token(); + _write_token(v0); _advance_token(1); goto .compile_global_initializer_end; .compile_global_initializer_record: - # Skip "S(". + (* Skip "S(". *) _advance_token(2); la t0, source_code_position @@ -1223,26 +1220,25 @@ begin li t1, ')' beq t0, t1, .compile_global_initializer_closing - # Skip comma and whitespace after it. + (* Skip comma and whitespace after it. *) _advance_token(2); goto .compile_global_initializer_loop; .compile_global_initializer_closing: - # Skip ")" + (* Skip ")" *) _advance_token(1); goto .compile_global_initializer_end; .compile_global_initializer_string: _write_z("\n\t.word strings + \0"); - _string_length(source_code_position); - sw a0, 4(sp) + v4 := _string_length(source_code_position); _add_string(source_code_position); _write_i(); - # Skip the quoted string. + (* Skip the quoted string. *) _advance_token(v4 + 2); goto .compile_global_initializer_end; @@ -1262,10 +1258,10 @@ begin _write_token(v0); _write_c(':'); - # Skip the constant name with assignment sign and surrounding whitespaces. + (* Skip the constant name with assignment sign and surrounding whitespaces. *) _advance_token(v0 + 4); _compile_global_initializer(); - # Skip semicolon and newline. + (* Skip semicolon and newline. *) _advance_token(2); _write_c('\n'); end; @@ -1277,7 +1273,7 @@ begin _memcmp(source_code_position, "const\0", 5); bnez a0, .compile_const_part_end - # Skip "const" with the newline after it. + (* Skip "const" with the newline after it. *) _advance_token(6); _write_z(".section .rodata # Compiled from const section.\n\n\0"); @@ -1288,19 +1284,13 @@ begin lw t0, (t0) lb t0, (t0) - # If the character at the line beginning is not indentation, - # it is probably the next code section. + (* If the character at the line beginning is not indentation, *) + (* it is probably the next code section. *) li t1, '\t' bne t0, t1, .compile_const_part_end _advance_token(1); - la t0, source_code_position - lw t0, (t0) - lb t0, (t0) - li t1, '#' - beq t0, t1, .compile_const_part_loop - _compile_constant_declaration(); goto .compile_const_part_loop; @@ -1309,8 +1299,7 @@ end; proc _compile_variable_declaration(); begin - _read_token(); - sw a0, 0(sp) + v0 := _read_token(); _write_z(".type \0"); _write_token(v0); @@ -1319,12 +1308,12 @@ begin _write_token(v0); _write_c(':'); - # Skip the variable name and colon with space before the type. + (* Skip the variable name and colon with space before the type. *) _advance_token(v0 + 2); - # Skip the type name. - _read_token(); - _advance_token(); + (* Skip the type name. *) + v4 := _read_token(); + _advance_token(v4); la t0, source_code_position lw t0, (t0) @@ -1332,18 +1321,18 @@ begin li t1, ' ' beq t0, t1, .compile_variable_declaration_initializer - # Else we assume this is a zeroed 81920 bytes big array. + (* Else we assume this is a zeroed 81920 bytes big array. *) _write_z(" .zero 81920\0"); goto .compile_variable_declaration_finalize; .compile_variable_declaration_initializer: - # Skip the assignment sign with surrounding whitespaces. + (* Skip the assignment sign with surrounding whitespaces. *) _advance_token(4); _compile_global_initializer(); goto .compile_variable_declaration_finalize; .compile_variable_declaration_finalize: - # Skip semicolon and newline. + (* Skip semicolon and newline. *) _advance_token(2); _write_c('\n'); end; @@ -1353,23 +1342,21 @@ begin _memcmp(source_code_position, "var\0", 3); bnez a0, .compile_var_part_end - # Skip "var" and newline. + (* Skip "var" and newline. *) _advance_token(4); _write_z(".section .data\n\0"); .compile_var_part_loop: + _skip_empty_lines(); + la t0, source_code_position lw t0, (t0) lb t0, (t0) - li t1, 'p' - beq t0, t1, .compile_var_part_end - li t1, '\t' beq t0, t1, .compile_var_part_declaration - _compile_line(); - goto .compile_var_part_loop; + goto .compile_var_part_end; .compile_var_part_declaration: _advance_token(1); @@ -1379,68 +1366,29 @@ begin .compile_var_part_end: end; -# Process the source code and print the generated code. +(* Process the source code and print the generated code. *) proc _compile_module(); begin _compile_const_part(); - _write_z(".section .bss\n\0"); - -.compile_module_bss: - la t0, source_code_position - lw t0, (t0) - lb t0, (t0) - li t1, 'v' - beq t0, t1, .compile_module_code - - li t1, 'p' - beq t0, t1, .compile_module_code - - _compile_line(); - goto .compile_module_bss; - -.compile_module_code: + _skip_empty_lines(); _compile_var_part(); + _write_z(".section .text\n\0"); .compile_module_loop: - _skip_newlines(); + _skip_empty_lines(); la t0, source_code_position lw t0, (t0) lb t0, (t0) beqz t0, .compile_module_end - li t1, '#' - beq t0, t1, .compile_module_comment - - # 8 is ".section" length. - _memcmp(source_code_position, ".section", 8); - beqz a0, .compile_module_section - # 5 is "proc " length. Space is needed to distinguish from "procedure". + (* 5 is "proc " length. Space is needed to distinguish from "procedure". *) _memcmp(source_code_position, "proc ", 5); beqz a0, .compile_module_procedure - # 6 is ".globl" length. - _memcmp(source_code_position, ".globl", 6); - beqz a0, .compile_module_global - - # Not a known token, exit. + (* Not a known token, exit. *) goto .compile_module_end; -.compile_module_section: - _compile_section(); - - goto .compile_module_loop; - -.compile_module_global: - _compile_line(); - - goto .compile_module_loop; - -.compile_module_comment: - _skip_comment(); - - goto .compile_module_loop; - .compile_module_procedure: _compile_procedure(); @@ -1457,20 +1405,17 @@ begin _write_z(".section .rodata\n.type strings, @object\nstrings: .ascii \0"); _write_c('"'); - la t0, compiler_strings - sw t0, 0(sp) + v0 := @compiler_strings; + v4 := compiler_strings_position; .compile_loop: lw t0, 0(sp) - la t1, compiler_strings_position - lw t1, (t1) + lw t1, 4(sp) bge t0, t1, .compile_end lb a0, (t0) - addi t0, t0, 1 sw t0, 0(sp) - _write_c(); j .compile_loop @@ -1480,24 +1425,520 @@ begin _write_c('\n'); end; -# Terminates the program. a0 contains the return code. -# -# Parameters: -# a0 - Status code. +(* Terminates the program. a0 contains the return code. *) + +(* Parameters: *) +(* a0 - Status code. *) proc _exit(); begin li a7, 93 # SYS_EXIT ecall end; -# Entry point. +(* Inserts a symbol into the table. *) + +(* Parameters: *) +(* a0 - Symbol pointer. *) +(* a1 - Symbol name length. *) +(* a2 - Symbol name pointer. *) +(* a3 - Symbol table. *) +proc _symbol_table_enter(); +begin + (* The first word in the symbol table is its length, get it. *) + lw a0, 76(sp) + lw a0, (a0) + sw a0, 0(sp) + + (* Calculate the offset for the new symbol. *) + v4 := v0 * 4; + v4 := v4 + 4; + v4 := v76 + 4; + + _memcpy(v4, @v80, 12); + + (* Increment the symbol table length. *) + v0 := v0 + 1; + lw t0, 0(sp) + lw t1, 76(sp) + sw t0, (t1) +end; + +proc _symbol_table_build(); +begin + _symbol_table_enter(@symbol_type_info_int, 3, symbol_builtin_name_int, @symbol_table_global); + _symbol_table_enter(@symbol_type_info_word, 4, symbol_builtin_name_word, @symbol_table_global); + _symbol_table_enter(@symbol_type_info_pointer, 7, symbol_builtin_name_pointer, @symbol_table_global); + _symbol_table_enter(@symbol_type_info_char, 4, symbol_builtin_name_char, @symbol_table_global); + _symbol_table_enter(@symbol_type_info_bool, 4, symbol_builtin_name_bool, @symbol_table_global); +end; + + +(* Classification table assigns each possible character to a group (class). All *) +(* characters of the same group a handled equivalently. *) + +(* Classification: *) + +(* TransitionClass = ( *) +(* transitionClassInvalid = 1, *) +(* transitionClassDigit = 2, *) +(* transitionClassAlpha = 3, *) +(* transitionClassSpace = 4, *) +(* transitionClassColon = 5, *) +(* transitionClassEquals = 6, *) +(* transitionClassLeftParen = 7, *) +(* transitionClassRightParen = 8, *) +(* transitionClassAsterisk = 9, *) +(* transitionClassUnderscore = 10, *) +(* transitionClassSingle = 11, *) +(* transitionClassHex = 12, *) +(* transitionClassZero = 13, *) +(* transitionClassX = 14, *) +(* transitionClassEof = 15, *) +(* transitionClassDot = 16, *) +(* transitionClassMinus = 17, *) +(* transitionClassSingleQuote = 18, *) +(* transitionClassDoubleQuote = 19, *) +(* transitionClassGreater = 20, *) +(* transitionClassLess = 21, *) +(* transitionClassOther = 22 *) +(* ); *) +(* TransitionState = ( *) +(* transitionStateStart = 1, *) +(* transitionStateColon = 2, *) +(* transitionStateIdentifier = 3, *) +(* transitionStateDecimal = 4, *) +(* transitionStateGreater = 5, *) +(* transitionStateMinus = 6, *) +(* transitionStateLeftParen = 7, *) +(* transitionStateLess = 8, *) +(* transitionStateDot = 9, *) +(* transitionStateComment = 10, *) +(* transitionStateClosingComment = 11, *) +(* transitionStateCharacter = 12, *) +(* transitionStateString = 13, *) +(* transitionStateLeadingZero = 14, *) +(* transitionStateDecimalSuffix = 15, *) +(* transitionStateEnd = 16 *) +(* ); *) +(* Transition = record *) +(* action: TransitionAction; *) +(* next_state: TransitionState *) +(* end; *) +(* TransitionAction = ( *) +(* none = 1, *) +(* accumulate = 2, *) +(* skip = 3, *) +(* single = 4, *) +(* eof = 5, *) +(* finalize = 6, *) +(* composite = 7, *) +(* key_id = 8, *) +(* integer = 9, *) +(* delimited = 10 *) +(* ); *) + +(* Assigns some value to at array index. *) + +(* Parameters: *) +(* a0 - Array pointer. *) +(* a1 - Index (word offset into the array). *) +(* a2 - Data to assign. *) +proc _assign_at(); +begin + v0 := v84 + -1; + v0 := v0 * 4; + v0 := v88 + v0; + + lw t0, 0(sp) + lw t1, 80(sp) + sw t1, (t0) +end; + +proc _initialize_classification(); +begin + _assign_at(@classification, 1, 15); + _assign_at(@classification, 2, 1); + _assign_at(@classification, 3, 1); + _assign_at(@classification, 4, 1); + _assign_at(@classification, 5, 1); + _assign_at(@classification, 6, 1); + _assign_at(@classification, 7, 1); + _assign_at(@classification, 8, 1); + _assign_at(@classification, 9, 1); + _assign_at(@classification, 10, 4); + _assign_at(@classification, 11, 4); + _assign_at(@classification, 12, 1); + _assign_at(@classification, 13, 1); + _assign_at(@classification, 14, 4); + _assign_at(@classification, 15, 1); + _assign_at(@classification, 16, 1); + _assign_at(@classification, 17, 1); + _assign_at(@classification, 18, 1); + _assign_at(@classification, 19, 1); + _assign_at(@classification, 20, 1); + _assign_at(@classification, 21, 1); + _assign_at(@classification, 22, 1); + _assign_at(@classification, 23, 1); + _assign_at(@classification, 24, 1); + _assign_at(@classification, 25, 1); + _assign_at(@classification, 26, 1); + _assign_at(@classification, 27, 1); + _assign_at(@classification, 28, 1); + _assign_at(@classification, 29, 1); + _assign_at(@classification, 30, 1); + _assign_at(@classification, 31, 1); + _assign_at(@classification, 32, 1); + _assign_at(@classification, 33, 4); + _assign_at(@classification, 34, 11); + _assign_at(@classification, 35, 19); + _assign_at(@classification, 36, 22); + _assign_at(@classification, 37, 22); + _assign_at(@classification, 38, 11); + _assign_at(@classification, 39, 11); + _assign_at(@classification, 40, 18); + _assign_at(@classification, 41, 7); + _assign_at(@classification, 42, 8); + _assign_at(@classification, 43, 9); + _assign_at(@classification, 44, 11); + _assign_at(@classification, 45, 11); + _assign_at(@classification, 46, 17); + _assign_at(@classification, 47, 16); + _assign_at(@classification, 48, 11); + _assign_at(@classification, 49, 13); + _assign_at(@classification, 50, 2); + _assign_at(@classification, 51, 2); + _assign_at(@classification, 52, 2); + _assign_at(@classification, 53, 2); + _assign_at(@classification, 54, 2); + _assign_at(@classification, 55, 2); + _assign_at(@classification, 56, 2); + _assign_at(@classification, 57, 2); + _assign_at(@classification, 58, 2); + _assign_at(@classification, 59, 5); + _assign_at(@classification, 60, 11); + _assign_at(@classification, 61, 21); + _assign_at(@classification, 62, 6); + _assign_at(@classification, 63, 20); + _assign_at(@classification, 64, 22); + _assign_at(@classification, 65, 11); + _assign_at(@classification, 66, 3); + _assign_at(@classification, 67, 3); + _assign_at(@classification, 68, 3); + _assign_at(@classification, 69, 3); + _assign_at(@classification, 70, 3); + _assign_at(@classification, 71, 3); + _assign_at(@classification, 72, 3); + _assign_at(@classification, 73, 3); + _assign_at(@classification, 74, 3); + _assign_at(@classification, 75, 3); + _assign_at(@classification, 76, 3); + _assign_at(@classification, 77, 3); + _assign_at(@classification, 78, 3); + _assign_at(@classification, 79, 3); + _assign_at(@classification, 80, 3); + _assign_at(@classification, 81, 3); + _assign_at(@classification, 82, 3); + _assign_at(@classification, 83, 3); + _assign_at(@classification, 84, 3); + _assign_at(@classification, 85, 3); + _assign_at(@classification, 86, 3); + _assign_at(@classification, 87, 3); + _assign_at(@classification, 88, 3); + _assign_at(@classification, 89, 3); + _assign_at(@classification, 90, 3); + _assign_at(@classification, 91, 3); + _assign_at(@classification, 92, 11); + _assign_at(@classification, 93, 22); + _assign_at(@classification, 94, 11); + _assign_at(@classification, 95, 11); + _assign_at(@classification, 96, 10); + _assign_at(@classification, 97, 22); + _assign_at(@classification, 98, 12); + _assign_at(@classification, 99, 12); + _assign_at(@classification, 100, 12); + _assign_at(@classification, 101, 12); + _assign_at(@classification, 102, 12); + _assign_at(@classification, 103, 12); + _assign_at(@classification, 104, 3); + _assign_at(@classification, 105, 3); + _assign_at(@classification, 106, 3); + _assign_at(@classification, 107, 3); + _assign_at(@classification, 108, 3); + _assign_at(@classification, 109, 3); + _assign_at(@classification, 110, 3); + _assign_at(@classification, 111, 3); + _assign_at(@classification, 112, 3); + _assign_at(@classification, 113, 3); + _assign_at(@classification, 114, 3); + _assign_at(@classification, 115, 3); + _assign_at(@classification, 116, 3); + _assign_at(@classification, 117, 3); + _assign_at(@classification, 118, 3); + _assign_at(@classification, 119, 3); + _assign_at(@classification, 120, 3); + _assign_at(@classification, 121, 14); + _assign_at(@classification, 122, 3); + _assign_at(@classification, 123, 3); + _assign_at(@classification, 124, 22); + _assign_at(@classification, 125, 11); + _assign_at(@classification, 126, 22); + _assign_at(@classification, 127, 11); + _assign_at(@classification, 128, 1); + + v0 := 129; + +(* Set the remaining 129 - 256 bytes to transitionClassOther. *) +.initialize_classification_loop: + _assign_at(@classification, v0, 22); + v0 := v0 + 1; + + lw t0, 0(sp) + li t1, 257 + blt t0, t1, .initialize_classification_loop +end; + +(* Parameters: *) +(* a0 - Current state (first index into transitions table). *) +(* a1 - Transition (second index into transitions table).. *) +(* a2 - Action to assign. *) +(* a3 - Next state to assign. *) +proc _set_transition(); +begin + (* Transitions start at offset in classification array. Save the transitions start in v0. *) + v0 := @classification + 256 + + (* Each state is 8 bytes long (2 words: action and next state). *) + (* There are 16 transition classes, so a transition 8 * 16 = 128 bytes long. *) + + v4 := v88 + -1; + v4 := v4 * 128; + + v8 := v84 + -1; + v8 := v8 * 8; + + v12 := v0 + v4; + v12 := v12 + v8; + + lw t0, 12(sp) + lw t1, 80(sp) + lw t2, 76(sp) + sw t1, (t0) + addi t0, t0, 4 + sw t2, (t0) +end; + +(* Parameters: *) +(* a0 - Current state (Transition state enumeration). *) +(* a1 - Default action (Callback). *) +(* a2 - Next state (Transition state enumeration). *) +proc _set_default_transition(); +begin + _set_transition(v88, 1, v84, v80); + _set_transition(v88, 2, v84, v80); + _set_transition(v88, 3, v84, v80); + _set_transition(v88, 4, v84, v80); + _set_transition(v88, 5, v84, v80); + _set_transition(v88, 6, v84, v80); + _set_transition(v88, 7, v84, v80); + _set_transition(v88, 8, v84, v80); + _set_transition(v88, 9, v84, v80); + _set_transition(v88, 10, v84, v80); + _set_transition(v88, 11, v84, v80); + _set_transition(v88, 12, v84, v80); + _set_transition(v88, 13, v84, v80); + _set_transition(v88, 14, v84, v80); + _set_transition(v88, 15, v84, v80); + _set_transition(v88, 16, v84, v80); + _set_transition(v88, 17, v84, v80); + _set_transition(v88, 18, v84, v80); + _set_transition(v88, 19, v84, v80); + _set_transition(v88, 20, v84, v80); + _set_transition(v88, 21, v84, v80); + _set_transition(v88, 22, v84, v80); +end; + + +(* The transition table describes transitions from one state to another, given *) +(* a symbol (character class). *) + +(* The table has m rows and n columns, where m is the amount of states and n is *) +(* the amount of classes. So given the current state and a classified character *) +(* the table can be used to look up the next state. *) + +(* Each cell is a word long. *) +(* - The least significant byte of the word is a row number (beginning with 0). *) +(* It specifies the target state. "ff" means that this is an end state and no *) +(* transition is possible. *) +(* - The next byte is the action that should be performed when transitioning. *) +(* For the meaning of actions see labels in the lex_next function, which *) +(* handles each action. *) +proc _initialize_transitions(); +begin + (* Start state. *) + _set_transition(1, 1, 1, 16); + _set_transition(1, 2, 2, 4); + _set_transition(1, 3, 2, 3); + _set_transition(1, 4, 3, 1); + _set_transition(1, 5, 2, 5); + _set_transition(1, 6, 4, 16); + _set_transition(1, 7, 2, 7); + _set_transition(1, 8, 4, 16); + _set_transition(1, 9, 4, 16); + _set_transition(1, 10, 2, 3); + _set_transition(1, 11, 4, 16); + _set_transition(1, 12, 2, 3); + _set_transition(1, 13, 2, 14); + _set_transition(1, 14, 2, 3); + _set_transition(1, 15, 5, 16); + _set_transition(1, 16, 2, 9); + _set_transition(1, 17, 2, 6); + _set_transition(1, 18, 2, 12); + _set_transition(1, 19, 2, 13); + _set_transition(1, 20, 2, 5); + _set_transition(1, 21, 2, 8); + _set_transition(1, 22, 1, 16); + + (* Colon state. *) + _set_default_transition(2, 6, 16); + _set_transition(2, 6, 7, 16); + + (* Identifier state. *) + _set_default_transition(3, 8, 16); + _set_transition(3, 2, 2, 3); + _set_transition(3, 3, 2, 3); + _set_transition(3, 10, 2, 3); + _set_transition(3, 12, 2, 3); + _set_transition(3, 13, 2, 3); + _set_transition(3, 14, 2, 3); + + (* Decimal state. *) + _set_default_transition(4, 9, 16); + _set_transition(4, 2, 2, 4); + _set_transition(4, 3, 2, 15); + _set_transition(4, 10, 1, 16); + _set_transition(4, 12, 2, 15); + _set_transition(4, 13, 2, 4); + _set_transition(4, 14, 2, 15); + + (* Greater state. *) + _set_default_transition(5, 6, 16); + _set_transition(5, 6, 7, 16); + + (* Minus state. *) + _set_default_transition(6, 6, 16); + _set_transition(6, 20, 7, 16); + + (* Left paren state. *) + _set_default_transition(7, 6, 16); + _set_transition(7, 9, 2, 10); + + (* Less state. *) + _set_default_transition(8, 6, 16); + _set_transition(8, 6, 7, 16); + _set_transition(8, 20, 7, 16); + + (* Hexadecimal after 0x. *) + _set_default_transition(9, 6, 16); + _set_transition(9, 16, 7, 16); + + (* Comment. *) + _set_default_transition(10, 2, 10); + _set_transition(10, 9, 2, 11); + _set_transition(10, 15, 1, 16); + + (* Closing comment. *) + _set_default_transition(11, 2, 10); + _set_transition(11, 1, 1, 16); + _set_transition(11, 8, 10, 16); + _set_transition(11, 9, 2, 11); + _set_transition(11, 15, 1, 16); + + (* Character. *) + _set_default_transition(12, 2, 12); + _set_transition(12, 1, 1, 16); + _set_transition(12, 15, 1, 16); + _set_transition(12, 18, 10, 16); + + (* String. *) + _set_default_transition(13, 2, 13); + _set_transition(13, 1, 1, 16); + _set_transition(13, 15, 1, 16); + _set_transition(13, 19, 10, 16); + + (* Leading zero. *) + _set_default_transition(14, 9, 16); + _set_transition(14, 2, 1, 16); + _set_transition(14, 3, 1, 16); + _set_transition(14, 10, 1, 16); + _set_transition(14, 12, 1, 16); + _set_transition(14, 13, 1, 16); + _set_transition(14, 14, 1, 16); + + (* Digit with a character suffix. *) + _set_default_transition(15, 9, 16); + _set_transition(15, 3, 1, 16); + _set_transition(15, 2, 1, 16); + _set_transition(15, 12, 1, 16); + _set_transition(15, 13, 1, 16); + _set_transition(15, 14, 1, 16); +end; + +proc _lexer_get_state(); +begin + (* Lexer state is saved after the transition tables. The offset is 256 + 16 * 22. *) + v0 := @classification; + v4 := 16 * 22; + v0 := v0 + 256; + + return v0 + v4 +end; + +(* Gets pointer to the current source text. *) +proc _lexer_get_current(); +begin + _lexer_get_state(); + sw a0, 0(sp) + + return v0 + 4 +end; + +(* Resets the lexer state for reading the next token. *) +proc _lexer_reset(); +begin + (* Transition start state is 1. *) + _lexer_get_state(); + li t0, 1 + sw t0, (a0) + sw a0, 0(sp) + + (* Text pointer to the beginning of the currently read token. *) + _lexer_get_current(); + la t0, source_code_position + lw t0, (t0) + sw t0, (a0) + + (* Initial length of the token is 0. *) + addi t0, t0, 4 + sw zero, (t0) +end; + +(* One time lexer initialization. *) +proc _lexer_initialize(); +begin + _initialize_classification(); + _initialize_transitions(); +end; + +(* Entry point. *) proc _start(); begin - # Read the source from the standard input. - # Second argument is buffer size. Modifying update the source_code definition. + _lexer_initialize(); + _symbol_table_build(); + + (* Read the source from the standard input. *) + (* Second argument is buffer size. Modifying update the source_code definition. *) _read_file(@source_code, 81920); _compile(); _exit(0); - end; |