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authorEugen Wissner <belka@caraus.de>2025-11-08 11:07:39 +0100
committerEugen Wissner <belka@caraus.de>2025-11-08 11:07:39 +0100
commitd144cb21012c911135d5047059449195a89ea239 (patch)
treedb8d8a69092192c07b2ab2c76bfd51848e3884fd /boot/stage8.elna
parent0b516345666b52d29bb10521b4d3c2c2420b3368 (diff)
downloadelna-d144cb21012c911135d5047059449195a89ea239.tar.gz
Move stages into subdirectories
Diffstat (limited to 'boot/stage8.elna')
-rw-r--r--boot/stage8.elna1989
1 files changed, 0 insertions, 1989 deletions
diff --git a/boot/stage8.elna b/boot/stage8.elna
deleted file mode 100644
index 75c24d7..0000000
--- a/boot/stage8.elna
+++ /dev/null
@@ -1,1989 +0,0 @@
-# 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 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.
-# - _syscall builtin. _syscall takes 7 arguments,
-# the 7th argument gets stored in a7 before invoking ecall.
-# Other arguments are saved in a0 through a5.
-# - New intrinsics: _load_byte, _load_word, _store_byte, _store_word.
-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);
-
-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.
-proc _string_length();
-begin
- # Reset the counter.
- v0 := 0;
-
-.string_length_loop:
- v88 := v88 + 1;
-
- lw t0, 88(sp)
- lb t0, (t0)
-
- li t1, '"'
- beq t0, t1, .string_length_end
-
- v0 := v0 + 1;
- goto .string_length_loop;
-
-.string_length_end:
- 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.
-proc _add_string();
-begin
- v0 := v88 + 1;
- v4 := compiler_strings_length;
-
-.add_string_loop:
- lw t0, 0(sp)
- lb t1, (t0)
- li t2, '"'
-
- beq t1, t2, .add_string_end
-
- la t2, compiler_strings_position
- lw t3, (t2)
- sb t1, (t3)
-
- addi t3, t3, 1
- sw t3, (t2)
-
- addi t0, t0, 1
- sw t0, 0(sp)
-
- li t2, '\\'
- bne t1, t2, .add_string_increment
-
- goto .add_string_loop;
-
-.add_string_increment:
- la t2, compiler_strings_length
- lw t4, (t2)
- addi t4, t4, 1
- sw t4, (t2)
-
- goto .add_string_loop;
-
-.add_string_end:
- return v4
-end;
-
-# 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.
- li a0, 0
- # SYS_READ.
- li a7, 63
- ecall
-end;
-
-# Writes to the standard output.
-#
-# Parameters:
-# a0 - Buffer.
-# a1 - Buffer length.
-proc _write_s();
-begin
- mv a2, a1
- mv a1, a0
- # STDOUT.
- li a0, 1
- # 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.
-proc _print_i();
-begin
- li t1, 10
- addi t0, s0, -9
-
- li t3, 0
- bgez a0, .print_i_digit10
- li t3, 1
- neg a0, a0
-
-.print_i_digit10:
- rem t2, a0, t1
- addi t2, t2, '0'
- sb t2, 0(t0)
- div a0, a0, t1
- addi t0, t0, -1
- bne zero, a0, .print_i_digit10
-
- beq zero, t3, .print_i_write_call
- addi t2, zero, '-'
- sb t2, 0(t0)
- addi t0, t0, -1
-
-.print_i_write_call:
- mv a0, a1
- addi a1, t0, 1
- sub a2, s0, t0
- addi a2, a2, -9
- sw a2, 0(sp)
-
- _memcpy();
-
- return v0
-end;
-
-# 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();
-
-end;
-
-# 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.
-proc _write_z();
-begin
-.write_z_loop:
- # Check for 0 character.
- lw a0, 88(sp)
- lb a0, (a0)
- beqz a0, .write_z_end
-
- # Print a character.
- _write_c();
-
- # Advance the input string by one byte.
- v88 := v88 + 1;
-
- goto .write_z_loop;
-
-.write_z_end:
-end;
-
-# Detects if a0 is an uppercase character. Sets a0 to 1 if so, otherwise to 0.
-proc _is_upper();
-begin
- v0 := v88 >= 'A';
- v4 := v88 <= 'Z';
-
- return v0 & v4
-
-end;
-
-# Detects if a0 is an lowercase character. Sets a0 to 1 if so, otherwise to 0.
-proc _is_lower();
-begin
- v0 := v88 >= 'a';
- v4 := v88 <= 'z';
-
- return v0 & v4
-
-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.
-proc _is_alpha();
-begin
- sw a0, 0(sp)
-
- _is_upper();
- sw a0, 4(sp)
-
- _is_lower(v0);
-
- lw t0, 0(sp)
- xori t1, t0, '_'
- seqz t1, t1
-
- lw t0, 4(sp)
- or a0, a0, t0
- or a0, a0, t1
-end;
-
-# 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.
-proc _is_digit();
-begin
- v0 := v88 >= '0';
- v4 := v88 <= '9';
-
- return v0 & v4
-end;
-
-proc _is_alnum();
-begin
- sw a0, 4(sp)
-
- _is_alpha();
- sw a0, 0(sp)
-
- _is_digit(v4);
-
- lw a1, 0(sp)
- or a0, a0, a1
-end;
-
-# Reads the next token.
-#
-# Returns token length in a0.
-proc _read_token();
-begin
- # Current token position.
- v0 := source_code_position;
- # Token length.
- v4 := 0;
-
-.read_token_loop:
- lw t0, 0(sp)
- # Current character.
- lb t0, (t0)
-
- # First we try to read a derictive.
- # A derictive can contain a dot and characters.
- li t1, '.'
- beq t0, t1, .read_token_next
-
- lw a0, 0(sp)
- lb a0, (a0)
- _is_alnum();
- bnez a0, .read_token_next
-
- goto .read_token_end;
-
-.read_token_next:
- # Advance the source code position and token length.
- v4 := v4 + 1;
- v0 := v0 + 1;
-
- goto .read_token_loop;
-
-.read_token_end:
- return v4
-end;
-
-# 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
- li a0, 0
-
-.memcmp_loop:
- beqz a2, .memcmp_end
-
- lbu t1, (t0)
- lbu t2, (a1)
- sub a0, t1, t2
-
- bnez a0, .memcmp_end
-
- addi t0, t0, 1
- addi a1, a1, 1
- addi a2, a2, -1
-
- goto .memcmp_loop;
-
-.memcmp_end:
-end;
-
-# Copies memory.
-#
-# Parameters:
-# a0 - Destination.
-# a1 - Source.
-# a2 - Size.
-#
-# Preserves a0.
-proc _memcpy();
-begin
- mv t0, a0
-
-.memcpy_loop:
- beqz a2, .memcpy_end
-
- lbu t1, (a1)
- sb t1, (a0)
-
- addi a0, a0, 1
- addi a1, a1, 1
- addi a2, a2, -1
-
- goto .memcpy_loop
-
-.memcpy_end:
- mv a0, t0
-end;
-
-# Advances the token stream by a0 bytes.
-proc _advance_token();
-begin
- la t0, source_code_position
- lw t1, (t0)
- add t1, t1, a0
- sw t1, (t0)
-end;
-
-# Prints the current token.
-#
-# Parameters:
-# a0 - Token length.
-#
-# Returns a0 unchanged.
-proc _write_token();
-begin
- _write_s(source_code_position, v88);
- return v88
-end;
-
-# Prints and skips a line.
-proc _compile_line();
-begin
-.compile_line_loop:
- la a0, source_code_position
- lw a1, (a0)
-
- lb t0, (a1)
- li t1, '\n'
- beq t0, t1, .compile_line_end
-
- # Print a character.
- lw a0, (a1)
- _write_c();
-
- # Advance the input string by one byte.
- _advance_token(1);
-
- goto .compile_line_loop;
-
-.compile_line_end:
- _write_c('\n');
-
- _advance_token(1);
-end;
-
-proc _compile_integer_literal();
-begin
- _write_z("\tli t0, \0");
-
- _read_token();
- _write_token();
- _advance_token();
-
- _write_c('\n');
-end;
-
-proc _compile_character_literal();
-begin
- _write_z("\tli t0, \0");
-
- _write_c('\'');
- _advance_token(1);
-
- la t0, source_code_position
- lw t0, (t0)
- lb a0, (t0)
- li t1, '\\'
- bne a0, t1, .compile_character_literal_end
-
- _write_c('\\');
- _advance_token(1);
-
-.compile_character_literal_end:
- la t0, source_code_position
- lw t0, (t0)
- lb a0, (t0)
- _write_c();
-
- _write_c('\'');
- _write_c('\n');
-
- _advance_token(2);
-
-end;
-
-proc _compile_variable_expression();
-begin
- _compile_designator();
- _write_z("\tlw t0, (t0)\n\0");
-end;
-
-proc _compile_address_expression();
-begin
- # Skip the "@" sign.
- _advance_token(1);
- _compile_designator();
-
-end;
-
-proc _compile_negate_expression();
-begin
- # Skip the "-" sign.
- _advance_token(1);
- _compile_term();
-
- _write_z("\tneg t0, t0\n\0");
-end;
-
-proc _compile_not_expression();
-begin
- # Skip the "~" sign.
- _advance_token(1);
- _compile_term();
-
- _write_z("\tnot t0, t0\n\0");
-end;
-
-proc _compile_string_literal();
-begin
- _string_length(source_code_position);
- sw a0, 0(sp)
-
- _add_string(source_code_position);
- sw a0, 4(sp)
-
- _advance_token(v0 + 2);
- _write_z("\tla t0, strings\n\0");
-
- _write_z("\tli t1, \0");
- _write_i(v4);
- _write_c('\n');
-
- _write_z("\tadd t0, t0, t1\n\0");
-end;
-
-proc _compile_term();
-begin
- la t0, source_code_position
- lw t0, (t0)
- lb a0, (t0)
- sw a0, 0(sp)
-
- li t1, '\''
- beq a0, t1, .compile_term_character_literal
-
- li t1, '@'
- beq a0, t1, .compile_term_address
-
- li t1, '-'
- beq a0, t1, .compile_term_negation
-
- li t1, '~'
- beq a0, t1, .compile_term_not
-
- 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
-
- goto .compile_term_variable;
-
-.compile_term_character_literal:
- _compile_character_literal();
- goto .compile_term_end;
-
-.compile_term_integer_literal:
- _compile_integer_literal();
- goto .compile_term_end;
-
-.compile_term_address:
- _compile_address_expression();
- goto .compile_term_end;
-
-.compile_term_negation:
- _compile_negate_expression();
- goto .compile_term_end;
-
-.compile_term_not:
- _compile_not_expression();
- goto .compile_term_end;
-
-.compile_term_string_literal:
- _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;
-
-.compile_term_end:
-end;
-
-proc _compile_binary_rhs();
-begin
- # Skip the whitespace after the binary operator.
- _advance_token(1);
- _compile_term();
-
- # Load the left expression from the stack;
- _write_z("\tlw t1, 24(sp)\n\0");
-end;
-
-proc _compile_expression();
-begin
- _compile_term();
-
- la t0, source_code_position
- lw t0, (t0)
- lb a0, (t0)
-
- li t1, ' '
- bne a0, t1, .compile_expression_end
-
- # It is a binary expression.
-
- # 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.
- _advance_token(1);
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
-
- li t1, '+'
- beq t0, t1, .compile_expression_add
-
- li t1, '*'
- beq t0, t1, .compile_expression_mul
-
- li t1, '&'
- beq t0, t1, .compile_expression_and
-
- li t1, 'o'
- beq t0, t1, .compile_expression_or
-
- li t1, 'x'
- beq t0, t1, .compile_expression_xor
-
- li t1, '='
- beq t0, t1, .compile_expression_equals
-
- li t1, '<'
- beq t0, t1, .compile_expression_less
-
- li t1, '>'
- beq t0, t1, .compile_expression_greater
-
- # Unknown binary operator.
- unimp
-
-.compile_expression_add:
- _advance_token(1);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("add t0, t0, t1\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_mul:
- _advance_token(1);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("\tmul t0, t0, t1\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_and:
- _advance_token(1);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("\tand t0, t0, t1\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_or:
- _advance_token(2);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("or t0, t0, t1\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_xor:
- _advance_token(3);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("xor t0, t0, t1\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_equals:
- _advance_token(1);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("xor t0, t0, t1\nseqz t0, t0\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_less:
- _advance_token(1);
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
-
- li t1, '>'
- beq t0, t1, .compile_expression_not_equal
-
- li t1, '='
- beq t0, t1, .compile_expression_less_equal
-
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("slt t0, t0, t1\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_not_equal:
- _advance_token(1);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("\txor t0, t0, t1\nsnez t0, t0\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_less_equal:
- _advance_token(1);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("\tslt t0, t0, t1\nxori t0, t0, 1\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_greater:
- _advance_token(1);
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
-
- li t1, '='
- beq t0, t1, .compile_expression_greater_equal
-
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("\tslt t0, t1, t0\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_greater_equal:
- _advance_token(1);
- _compile_binary_rhs();
-
- # Execute the operation.
- _write_z("\tslt t0, t1, t0\nxori t0, t0, 1\n\0");
-
- goto .compile_expression_end;
-
-.compile_expression_end:
-end;
-
-proc _compile_call();
-begin
- # Stack variables:
- # v0 - Procedure name length.
- # v4 - Procedure name pointer.
- # v8 - Argument count.
-
- _read_token();
- sw a0, 0(sp)
- v4 := source_code_position;
- v8 := 0;
-
- # Skip the identifier and left paren.
- _advance_token(v0 + 1);
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
-
- li t1, ')'
- beq t0, t1, .compile_call_finalize
-
-.compile_call_loop:
- _compile_expression();
-
- # Save the argument on the stack.
- _write_z("\tsw t0, \0");
-
- # 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.
- v8 := v8 + 1;
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
-
- li t1, ','
- bne t0, t1, .compile_call_finalize
-
- _advance_token(2);
- goto .compile_call_loop;
-
-.compile_call_finalize:
- # Load the argument from the stack.
-
- lw t0, 8(sp)
- beqz t0, .compile_call_end
-
- # Decrement the argument counter.
- v8 := v8 + -1;
-
- _write_z("\tlw a\0");
- _write_i(v8);
-
- _write_z(", \0");
-
- # Calculate the stack offset: 116 - (4 * argument_counter)
- v12 := v8 * 4;
- v12 := 116 + -v12;
- _write_i(v12);
-
- _write_z("(sp)\n\0");
-
- goto .compile_call_finalize;
-
-.compile_call_end:
- _write_z("\tcall \0");
- _write_s(v4, v0);
-
- # Skip the right paren.
- _advance_token(1);
-end;
-
-proc _compile_goto();
-begin
- _advance_token(5);
-
- _read_token();
- sw a0, 0(sp)
-
- _write_z("\tj \0");
-
- _write_token(v0);
- _advance_token();
-end;
-
-proc _compile_local_designator();
-begin
- # 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();
- _write_c('\n');
-end;
-
-proc _compile_global_designator();
-begin
- _write_z("\tla t0, \0");
-
- _read_token();
- _write_token();
- _advance_token();
-
- _write_c('\n');
-end;
-
-proc _compile_designator();
-begin
- la t0, source_code_position
- lw t0, (t0)
- lb a0, (t0)
-
- li t1, 'v'
- beq a0, t1, .compile_designator_local
-
- goto .compile_designator_global;
-
-.compile_designator_local:
- _compile_local_designator();
- goto .compile_designator_end;
-
-.compile_designator_global:
- _compile_global_designator();
- goto .compile_designator_end;
-
-.compile_designator_end:
-end;
-
-proc _compile_assignment();
-begin
- _compile_designator();
-
- # Save the assignee address on the stack.
- _write_z("\tsw t0, 20(sp)\n\0");
-
- # Skip the assignment sign (:=) with surrounding whitespaces.
- _advance_token(4);
-
- # Compile the assignment.
- _compile_expression();
-
- _write_z("\tlw t1, 20(sp)\nsw t0, (t1)\n\0");
-end;
-
-proc _compile_return_statement();
-begin
- # Skip "return" keyword and whitespace after it.
- _advance_token(7);
- _compile_expression();
-
- _write_z("mv a0, t0\n\0");
-end;
-
-proc _compile_statement();
-begin
- # This is a call if the statement starts with an underscore.
- la t0, source_code_position
- lw t0, (t0)
- # First character after alignment tab.
- addi t0, t0, 1
- lb t0, (t0)
-
- li t1, '_'
- beq t0, t1, .compile_statement_call
-
- li t1, 'g'
- beq t0, t1, .compile_statement_goto
-
- li t1, 'v'
- beq t0, t1, .compile_statement_assignment
-
- # keyword_ret contains "\tret", so it's 4 bytes long.
- _memcmp(source_code_position, "\treturn", 7);
- beqz a0, .compile_statement_return
-
- _compile_line();
- goto .compile_statement_end;
-
-.compile_statement_call:
- _advance_token(1);
- _compile_call();
-
- goto .compile_statement_semicolon;
-
-.compile_statement_goto:
- _advance_token(1);
- _compile_goto();
-
- goto .compile_statement_semicolon;
-
-.compile_statement_assignment:
- _advance_token(1);
- _compile_assignment();
-
- goto .compile_statement_semicolon;
-
-.compile_statement_return:
- _advance_token(1);
- _compile_return_statement();
- _write_c('\n');
-
- goto .compile_statement_end;
-
-.compile_statement_semicolon:
- _advance_token(2);
- _write_c('\n');
-
-.compile_statement_end:
-end;
-
-proc _compile_procedure_body();
-begin
-.compile_procedure_body_loop:
- _skip_empty_lines();
-
- # 3 is "end" length.
- _memcmp(source_code_position, "end", 3);
-
- beqz a0, .compile_procedure_body_epilogue
-
- _compile_statement();
- goto .compile_procedure_body_loop;
-
-.compile_procedure_body_epilogue:
-end;
-
-# Writes a regster name to the standard output.
-#
-# Parameters:
-# a0 - Register character.
-# a1 - Register number.
-proc _write_register();
-begin
- _write_c(v88);
- v84 := v84 + '0';
- _write_c(v84);
-end;
-
-proc _compile_procedure_prologue();
-begin
- _write_z("\taddi sp, sp, -128\n\tsw ra, 124(sp)\n\tsw s0, 120(sp)\n\taddi s0, sp, 128\n\0");
- v0 := 0;
-
-.compile_procedure_prologue_loop:
- _write_z("\tsw a\0");
- _write_i(v0);
- _write_z(", \0");
-
- # Calculate the stack offset: 88 - (4 * parameter_counter)
- v4 := v0 * 4;
- v4 := 88 + -v4;
- _write_i(v4);
-
- _write_z("(sp)\n\0");
-
- v0 := v0 + 1;
- lw a0, 0(sp)
-
- li t0, 8
- bne a0, t0, .compile_procedure_prologue_loop
-end;
-
-proc _compile_procedure();
-begin
- # Skip "proc ".
- _advance_token(5);
-
- _read_token();
- # Save the procedure name length.
- sw a0, 0(sp)
-
- # Write .type _procedure_name, @function.
- _write_z(".type \0");
-
- _write_token(v0);
- _write_z(", @function\n\0");
-
- # Write procedure label, _procedure_name:
- _write_token(v0);
- _write_z(":\n\0");
-
- # 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_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.
- _advance_token(5);
-end;
-
-proc _skip_newlines();
-begin
- # Skip newlines.
- la t0, source_code_position
- lw t1, (t0)
-
-.skip_newlines_loop:
- lb t2, (t1)
- li t3, '\n'
- bne t2, t3, .skip_newlines_end
- beqz t2, .skip_newlines_end
-
- addi t1, t1, 1
- sw t1, (t0)
-
- goto .skip_newlines_loop;
-
-.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_rerun:
- la t0, source_code_position
- lw 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
-
- 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_rerun;
-
-.skip_empty_lines_newline:
- 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;
-
-proc _compile_global_initializer();
-begin
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
-
- li t1, '"'
- beq t0, t1, .compile_global_initializer_string
-
- li t1, 'S'
- beq t0, t1, .compile_global_initializer_record
-
- li t1, '@'
- beq t0, t1, .compile_global_initializer_pointer
-
- la a0, source_code_position
- lw a0, (a0)
- lb a0, (a0)
- _is_digit();
- bnez a0, .compile_global_initializer_number
-
- unimp
-
-.compile_global_initializer_pointer:
- # Skip @.
- _advance_token(1);
- _write_z("\n\t.word \0");
- _read_token();
- _write_token();
- _advance_token();
-
- goto .compile_global_initializer_end;
-
-.compile_global_initializer_number:
- _write_z("\n\t.word \0");
- _read_token();
- _write_token();
- _advance_token(1);
-
- goto .compile_global_initializer_end;
-
-.compile_global_initializer_record:
- # Skip "S(".
- _advance_token(2);
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
- li t1, ')'
- beq t0, t1, .compile_global_initializer_closing
-
-.compile_global_initializer_loop:
- _compile_global_initializer();
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
- li t1, ')'
- beq t0, t1, .compile_global_initializer_closing
-
- # Skip comma and whitespace after it.
- _advance_token(2);
-
- goto .compile_global_initializer_loop;
-
-.compile_global_initializer_closing:
- # 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)
-
- _add_string(source_code_position);
- _write_i();
-
- # Skip the quoted string.
- _advance_token(v4 + 2);
-
- goto .compile_global_initializer_end;
-
-.compile_global_initializer_end:
-end;
-
-proc _compile_constant_declaration();
-begin
- _read_token();
- sw a0, 0(sp)
-
- _write_z(".type \0");
- _write_token(v0);
- _write_z(", @object\n\0");
-
- _write_token(v0);
- _write_c(':');
-
- # Skip the constant name with assignment sign and surrounding whitespaces.
- _advance_token(v0 + 4);
- _compile_global_initializer();
- # Skip semicolon and newline.
- _advance_token(2);
- _write_c('\n');
-end;
-
-proc _compile_const_part();
-begin
- _skip_empty_lines();
-
- _memcmp(source_code_position, "const\0", 5);
- bnez a0, .compile_const_part_end
-
- # Skip "const" with the newline after it.
- _advance_token(6);
- _write_z(".section .rodata # Compiled from const section.\n\n\0");
-
-.compile_const_part_loop:
- _skip_empty_lines();
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
-
- # 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);
-
- _compile_constant_declaration();
- goto .compile_const_part_loop;
-
-.compile_const_part_end:
-end;
-
-proc _compile_variable_declaration();
-begin
- _read_token();
- sw a0, 0(sp)
-
- _write_z(".type \0");
- _write_token(v0);
- _write_z(", @object\n\0");
-
- _write_token(v0);
- _write_c(':');
-
- # Skip the variable name and colon with space before the type.
- _advance_token(v0 + 2);
-
- # Skip the type name.
- _read_token();
- _advance_token();
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
- li t1, ' '
- beq t0, t1, .compile_variable_declaration_initializer
-
- # 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.
- _advance_token(4);
- _compile_global_initializer();
- goto .compile_variable_declaration_finalize;
-
-.compile_variable_declaration_finalize:
- # Skip semicolon and newline.
- _advance_token(2);
- _write_c('\n');
-end;
-
-proc _compile_var_part();
-begin
- _memcmp(source_code_position, "var\0", 3);
- bnez a0, .compile_var_part_end
-
- # 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, '\t'
- beq t0, t1, .compile_var_part_declaration
-
- goto .compile_var_part_end;
-
-.compile_var_part_declaration:
- _advance_token(1);
- _compile_variable_declaration();
- goto .compile_var_part_loop;
-
-.compile_var_part_end:
-end;
-
-# Process the source code and print the generated code.
-proc _compile_module();
-begin
- _compile_const_part();
- _skip_empty_lines();
- _compile_var_part();
-
- _write_z(".section .text\n\n\0");
- _write_z(".type _syscall, @function\n_syscall:\n\tmv a7, a6\n\tecall\n\tret\n\n\0");
- _write_z(".type _load_byte, @function\n_load_byte:\n\tlb a0, (a0)\nret\n\n\0");
- _write_z(".type _load_word, @function\n_load_word:\n\tlw a0, (a0)\nret\n\n\0");
- _write_z(".type _store_byte, @function\n_store_byte:\n\tsb a0, (a1)\nret\n\n\0");
- _write_z(".type _store_word, @function\n_store_word:\n\tsw a0, (a1)\nret\n\n\0");
-
-.compile_module_loop:
- _skip_empty_lines();
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
- beqz t0, .compile_module_end
-
- # 5 is "proc " length. Space is needed to distinguish from "procedure".
- _memcmp(source_code_position, "proc ", 5);
- beqz a0, .compile_module_procedure
-
- # Not a known token, exit.
- goto .compile_module_end;
-
-.compile_module_procedure:
- _compile_procedure();
-
- goto .compile_module_loop;
-
-.compile_module_end:
-end;
-
-proc _compile();
-begin
- _write_z(".globl _start\n\n\0");
- _compile_module();
-
- _write_z(".section .rodata\n.type strings, @object\nstrings: .ascii \0");
- _write_c('"');
-
- la t0, compiler_strings
- sw t0, 0(sp)
-
-.compile_loop:
- lw t0, 0(sp)
- la t1, compiler_strings_position
- lw t1, (t1)
- bge t0, t1, .compile_end
-
- lb a0, (t0)
-
- addi t0, t0, 1
- sw t0, 0(sp)
-
- _write_c();
-
- j .compile_loop
-
-.compile_end:
- _write_c('"');
- _write_c('\n');
-end;
-
-# Terminates the program. a0 contains the return code.
-#
-# Parameters:
-# a0 - Status code.
-proc _exit();
-begin
- li a7, 93 # SYS_EXIT
- 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;