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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/stage2.elna
parent0b516345666b52d29bb10521b4d3c2c2420b3368 (diff)
downloadelna-d144cb21012c911135d5047059449195a89ea239.tar.gz
Move stages into subdirectories
Diffstat (limited to 'boot/stage2.elna')
-rw-r--r--boot/stage2.elna859
1 files changed, 0 insertions, 859 deletions
diff --git a/boot/stage2.elna b/boot/stage2.elna
deleted file mode 100644
index 0423b3b..0000000
--- a/boot/stage2.elna
+++ /dev/null
@@ -1,859 +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 2 compiler.
-#
-# - Procedures without none or one argument.
-# - Goto statements.
-# - Character and integer literals.
-# - Passing local variables to procedures.
-# - Local variables should have the format: v00,
-# where 00 is its offset from the sp register.
-
-.section .rodata
-
-.type keyword_equ, @object
-keyword_equ: .ascii ".equ"
-.equ KEYWORD_EQU_SIZE, 4
-
-.type keyword_section, @object
-keyword_section: .ascii ".section"
-.equ KEYWORD_SECTION_SIZE, 8
-
-.type keyword_type, @object
-keyword_type: .ascii ".type"
-.equ KEYWORD_TYPE_SIZE, 5
-
-.type keyword_ret, @object
-keyword_ret: .ascii "ret"
-.equ KEYWORD_RET_SIZE, 3
-
-.type keyword_global, @object
-keyword_global: .ascii ".globl"
-.equ KEYWORD_GLOBAL_SIZE, 6
-
-.type keyword_proc, @object
-keyword_proc: .ascii "proc "
-.equ KEYWORD_PROC_SIZE, 5
-
-.type keyword_end, @object
-keyword_end: .ascii "end"
-.equ KEYWORD_END_SIZE, 3
-
-.type keyword_begin, @object
-keyword_begin: .ascii "begin"
-.equ KEYWORD_BEGIN_SIZE, 5
-
-.type keyword_var, @object
-keyword_var: .ascii "var"
-.equ KEYWORD_VAR_SIZE, 3
-
-.type asm_prologue, @object
-asm_prologue: .string "\taddi sp, sp, -32\n\tsw ra, 28(sp)\n\tsw s0, 24(sp)\n\taddi s0, sp, 32\n"
-
-.type asm_epilogue, @object
-asm_epilogue: .string "\tlw ra, 28(sp)\n\tlw s0, 24(sp)\n\taddi sp, sp, 32\n\tret\n"
-
-.type asm_type_directive, @object
-asm_type_directive: .string ".type "
-
-.type asm_type_function, @object
-asm_type_function: .string ", @function\n"
-
-.type asm_colon, @object
-asm_colon: .string ":\n"
-
-.type asm_call, @object
-asm_call: .string "\tcall "
-
-.type asm_j, @object
-asm_j: .string "\tj "
-
-.type asm_li, @object
-asm_li: .string "\tli "
-
-.type asm_lw, @object
-asm_lw: .string "\tlw "
-
-.type asm_t0, @object
-asm_t0: .string "t0"
-
-.type asm_a0, @object
-asm_a0: .string "a0"
-
-.type asm_comma, @object
-asm_comma: .string ", "
-
-.type asm_sp, @object
-asm_sp: .string "(sp)"
-
-.section .bss
-
-.equ SOURCE_BUFFER_SIZE, 81920
-.type source_code, @object
-source_code: .zero SOURCE_BUFFER_SIZE
-
-.section .data
-
-.type source_code_position, @object
-source_code_position: .word source_code
-
-.section .text
-
-# 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
- li a7, 63 # SYS_READ.
- ecall
-end;
-
-# Writes to the standard output.
-#
-# Parameters:
-# a0 - Buffer.
-# a1 - Buffer length.
-proc _write();
-begin
- mv a2, a1
- mv a1, a0
- # STDOUT.
- li a0, 1
- li a7, 64 # SYS_WRITE.
- ecall
-end;
-
-# Writes a character from a0 into the standard output.
-proc _write_c();
-begin
- sb a0, 20(sp)
- addi a0, sp, 20
- li a1, 1
- _write();
-end;
-
-# Write null terminated string.
-#
-# Parameters:
-# a0 - String.
-proc _write_z();
-begin
- sw a0, 20(sp)
-
-.write_z_loop:
- # Check for 0 character.
- lb a0, (a0)
- beqz a0, .write_z_end
-
- # Print a character.
- lw a0, 20(sp)
- lb a0, (a0)
- _write_c();
-
- # Advance the input string by one byte.
- lw a0, 20(sp)
- addi a0, a0, 1
- sw a0, 20(sp)
-
- j .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
- li t0, 'A' - 1
- sltu t1, t0, a0 # t1 = a0 >= 'A'
-
- sltiu t2, a0, 'Z' + 1 # t2 = a0 <= 'Z'
- and a0, t1, t2 # t1 = a0 >= 'A' & a0 <= 'Z'
-end;
-
-# Detects if a0 is an lowercase character. Sets a0 to 1 if so, otherwise to 0.
-proc _is_lower();
-begin
- li t0, 'a' - 1
- sltu t2, t0, a0 # t2 = a0 >= 'a'
-
- sltiu t3, a0, 'z' + 1 # t3 = a0 <= 'z'
- and a0, t2, t3 # t2 = a0 >= 'a' & a0 <= 'z'
-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, 20(sp)
-
- _is_upper();
- sw a0, 16(sp)
-
- lw a0, 20(sp)
- _is_lower();
-
- lw t0, 20(sp)
- xori t1, t0, '_'
- seqz t1, t1
-
- lw t0, 16(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
- li t0, '0' - 1
- sltu t1, t0, a0 # t1 = a0 >= '0'
-
- sltiu t2, a0, '9' + 1 # t2 = a0 <= '9'
-
- and a0, t1, t2
-end;
-
-# Reads the next token.
-#
-# Returns token length in a0.
-proc _read_token();
-begin
- la t0, source_code_position # Token pointer.
- lw t0, (t0)
- sw t0, 20(sp) # Current token position.
- sw zero, 16(sp) # Token length.
-
-.read_token_loop:
- lb t0, (t0) # Current character.
-
- # 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, 20(sp)
- lb a0, (a0)
- _is_alpha();
- bnez a0, .read_token_next
-
- lw a0, 20(sp)
- lb a0, (a0)
- _is_digit();
- bnez a0, .read_token_next
-
- j .read_token_end
-
-.read_token_next:
- # Advance the source code position and token length.
- lw t0, 16(sp)
- addi t0, t0, 1
- sw t0, 16(sp)
-
- lw t0, 20(sp)
- addi t0, t0, 1
- sw t0, 20(sp)
-
- j .read_token_loop
-
-.read_token_end:
- lw a0, 16(sp)
-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
-
-.Lmemcmp_loop:
- beqz a2, .Lmemcmp_end
-
- lbu t1, (t0)
- lbu t2, (a1)
- sub a0, t1, t2
-
- bnez a0, .Lmemcmp_end
-
- addi t0, t0, 1
- addi a1, a1, 1
- addi a2, a2, -1
-
- j .Lmemcmp_loop
-
-.Lmemcmp_end:
-end;
-
-# Advances the token stream by a0 bytes.
-proc _advance_token();
-begin
- # Skip the .equ directive.
- 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
- sw a0, 20(sp)
-
- la a0, source_code_position
- lw a0, (a0)
- lw a1, 20(sp)
- _write();
-
- lw a0, 20(sp)
-end;
-
-proc _compile_section();
-begin
- # Print and skip the .section directive and a space after it.
- li a0, KEYWORD_SECTION_SIZE + 1
- _write_token();
- _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)
-
- j .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
-.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.
- li a0, 1
- _advance_token();
-
- j .compile_line_loop
-
-.compile_line_end:
- li a0, '\n'
- _write_c();
-
- li a0, 1
- _advance_token();
-end;
-
-proc _compile_integer_literal();
-begin
- la a0, asm_li
- _write_z();
-
- la a0, asm_a0
- _write_z();
-
- la a0, asm_comma
- _write_z();
-
- _read_token();
- _write_token();
- _advance_token();
-
- li a0, '\n'
- _write_c();
-end;
-
-proc _compile_character_literal();
-begin
- la a0, asm_li
- _write_z();
-
- la a0, asm_a0
- _write_z();
-
- la a0, asm_comma
- _write_z();
-
-.compile_character_literal_loop:
- la a0, source_code_position
- lw a0, (a0)
- li a1, 1
- _write();
- li a0, 1
- _advance_token();
-
- la t0, source_code_position
- lw t0, (t0)
- lb a0, (t0)
- li t1, '\''
- beq a0, t1, .compile_character_literal_end
-
- j .compile_character_literal_loop
-
-.compile_character_literal_end:
- li a0, '\''
- _write_c();
-
- li a0, '\n'
- _write_c();
-
- li a0, 1
- _advance_token();
-end;
-
-proc _compile_variable_expression();
-begin
- la a0, asm_lw
- _write_z();
-
- la a0, asm_a0
- _write_z();
-
- la a0, asm_comma
- _write_z();
-
- la a0, source_code_position
- lw a0, (a0)
- addi a0, a0, 1
- li a1, 2
- _write();
-
- la a0, asm_sp
- _write_z();
-
- li a0, '\n'
- _write_c();
-
- li a0, 3
- _advance_token();
-
-end;
-
-proc _compile_expression();
-begin
- la t0, source_code_position
- lw t0, (t0)
- lb a0, (t0)
-
- li t1, '\''
- beq a0, t1, .compile_expression_character_literal
-
- li t1, 'v'
- beq a0, t1, .compile_expression_variable
-
- _is_digit();
- bnez a0, .compile_expression_integer_literal
-
- j .compile_expression_end
-
-.compile_expression_character_literal:
- _compile_character_literal();
- j .compile_expression_end
-
-.compile_expression_integer_literal:
- _compile_integer_literal();
- j .compile_expression_end
-
-.compile_expression_variable:
- _compile_variable_expression();
- j .compile_expression_end;
-
-.compile_expression_end:
-end;
-
-proc _compile_call();
-begin
- _read_token();
- sw a0, 20(sp)
- la t0, source_code_position
- lw t0, (t0)
- sw t0, 16(sp)
-
- # Skip the identifier and left paren.
- addi a0, a0, 1
- _advance_token();
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
-
- li t1, ')'
- beq t0, t1, .compile_call_finalize
-
- _compile_expression();
-
-.compile_call_finalize:
- la a0, asm_call
- _write_z();
-
- lw a0, 16(sp)
- lw a1, 20(sp)
- _write();
-
- # Skip the right paren.
- li a0, 1
- _advance_token();
-end;
-
-proc _compile_goto();
-begin
- li a0, 5
- _advance_token();
-
- _read_token();
- sw a0, 20(sp)
-
- la a0, asm_j
- _write_z();
-
- lw a0, 20(sp)
- _write_token();
- _advance_token();
-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
-
- _compile_line();
- j .compile_statement_end
-
-.compile_statement_call:
- li a0, 1
- _advance_token();
- _compile_call();
-
- j .compile_statement_semicolon
-
-.compile_statement_goto:
- li a0, 1
- _advance_token();
- _compile_goto();
-
- j .compile_statement_semicolon
-
-.compile_statement_semicolon:
- li a0, 2
- _advance_token();
-
- li a0, '\n'
- _write_c();
-
-.compile_statement_end:
-end;
-
-proc _compile_procedure_body();
-begin
-.compile_procedure_body_loop:
- la a0, source_code_position
- lw a0, (a0)
- la a1, keyword_end
- li a2, KEYWORD_END_SIZE
- _memcmp();
-
- beqz a0, .compile_procedure_body_epilogue
-
- _compile_statement();
- j .compile_procedure_body_loop
-
-.compile_procedure_body_epilogue:
-end;
-
-proc _compile_procedure();
-begin
- # Skip "proc ".
- li a0, KEYWORD_PROC_SIZE
- _advance_token();
-
- _read_token();
- sw a0, 20(sp) # Save the procedure name length.
-
- # Write .type _procedure_name, @function.
- la a0, asm_type_directive
- _write_z();
-
- lw a0, 20(sp)
- _write_token();
-
- la a0, asm_type_function
- _write_z();
-
- # Write procedure label, _procedure_name:
- lw a0, 20(sp)
- _write_token();
-
- la a0, asm_colon
- _write_z();
-
- # Skip the function name and trailing parens, semicolon, "begin" and newline.
- lw a0, 20(sp)
- addi a0, a0, KEYWORD_BEGIN_SIZE + 1 + 4
- _advance_token();
-
- la a0, asm_prologue
- _write_z();
-
- _compile_procedure_body();
-
- # Write the epilogue.
- la a0, asm_epilogue
- _write_z();
-
- li a0, KEYWORD_END_SIZE + 2
- _advance_token();
-end;
-
-proc _compile_type();
-begin
- # Print and skip the .type directive and a space after it.
- li a0, KEYWORD_TYPE_SIZE + 1
- _write_token();
- _advance_token();
-
- # Read and print the symbol name.
- _read_token();
- sw a0, 20(sp)
-
- # Print and skip the symbol name, comma, space and @.
- lw a0, 20(sp)
- addi a0, a0, 3
- _write_token();
- _advance_token();
-
- # Read the symbol type.
- _read_token();
- sw a0, 16(sp)
- la t0, source_code_position
- lw t0, (t0)
- sw t0, 12(sp)
-
- # Print the symbol type and newline.
- lw a0, 16(sp)
- addi a0, a0, 1
- _write_token();
- _advance_token();
-
- # Write the object definition itself.
- _compile_line();
-
-.compile_type_end:
-end;
-
-proc _compile_equ();
-begin
- # Print and skip the .equ directive and a space after it.
- li a0, KEYWORD_EQU_SIZE + 1
- _write_token();
- _advance_token();
-
- # Read and print the constant name.
- _read_token();
- sw a0, 20(sp)
-
- # Print and skip the constant name, comma and space.
- lw a0, 20(sp)
- addi a0, a0, 2
- _write_token();
- _advance_token();
-
- # Read the constant value.
- _read_token();
- sw a0, 16(sp)
-
- # Print and skip the constant value and newline.
- lw a0, 16(sp)
- addi a0, a0, 1
- _write_token();
- _advance_token();
-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)
-
- j .skip_newlines_loop
-
-.skip_newlines_end:
-end;
-
-# Process the source code and print the generated code.
-proc _compile();
-begin
-.compile_loop:
- _skip_newlines();
-
- la t0, source_code_position
- lw t0, (t0)
- lb t0, (t0)
- beqz t0, .compile_end
- li t1, '#'
- beq t0, t1, .compile_comment
-
- la a0, source_code_position
- lw a0, (a0)
- la a1, keyword_equ
- li a2, KEYWORD_EQU_SIZE
- _memcmp();
-
- beqz a0, .compile_equ
-
- la a0, source_code_position
- lw a0, (a0)
- la a1, keyword_section
- li a2, KEYWORD_SECTION_SIZE
- _memcmp();
-
- beqz a0, .compile_section
-
- la a0, source_code_position
- lw a0, (a0)
- la a1, keyword_type
- li a2, KEYWORD_TYPE_SIZE
- _memcmp();
-
- beqz a0, .compile_type
-
- la a0, source_code_position
- lw a0, (a0)
- la a1, keyword_proc
- li a2, KEYWORD_PROC_SIZE
- _memcmp();
-
- beqz a0, .compile_procedure
-
- la a0, source_code_position
- lw a0, (a0)
- la a1, keyword_global
- li a2, KEYWORD_GLOBAL_SIZE
- _memcmp();
-
- beqz a0, .compile_global
- # Not a known token, exit.
- j .compile_end
-
-.compile_equ:
- _compile_equ();
-
- j .compile_loop
-
-.compile_section:
- _compile_section();
-
- j .compile_loop
-
-.compile_type:
- _compile_type();
-
- j .compile_loop
-
-.compile_global:
- _compile_line();
-
- j .compile_loop
-
-.compile_comment:
- _skip_comment();
-
- j .compile_loop
-
-.compile_procedure:
- _compile_procedure();
-
- j .compile_loop
-
-.compile_end:
-end;
-
-# Entry point.
-.globl _start
-proc _start();
-begin
- # Read the source from the standard input.
- la a0, source_code
- li a1, SOURCE_BUFFER_SIZE # Buffer size.
- _read_file();
- _compile();
-
- # Call exit.
- li a0, 0 # Use 0 return code.
- li a7, 93 # SYS_EXIT.
- ecall
-end;