elna/boot/stage1.s

1527 lines
28 KiB
ArmAsm

# 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/.
.global _start # Program entry point.
#
# Registers used as global variables:
# s1 - Contains the current position in the source text.
# s2 - Label counter.
#
# - The compiler expects valid input, otherwise it will generate invalid
# assembly or hang. There is no error checking, no semantic analysis, no
# type checking.
#
# - Imports with only a module name without package, e.g.
# "import dummy", can be parsed, but are ignored.
#
# - No loops. Only labels and goto.
#
# - Only unsigned number literals are supported (in decimal or
# hexadecimal format).
#
# - Comments are accepted only at the end of a line.
#
# - Return can be used only as the last statement of a procedure. It
# doesn't actually return, but sets a0 to the appropriate value.
#
# - The lvalue of an assignment can only be an identifier.
.include "boot/definitions.inc"
.equ SOURCE_BUFFER_SIZE, 81920
.section .rodata
section_rodata: .ascii ".section .rodata\n"
.equ SECTION_RODATA_SIZE, . - section_rodata
section_text: .ascii ".section .text\n"
.equ SECTION_TEXT_SIZE, . - section_text
section_bss: .ascii ".section .bss\n"
.equ SECTION_BSS_SIZE, . - section_bss
global_start: .ascii ".global _start\n"
.equ GLOBAL_START_SIZE, . - global_start
prologue: .ascii "addi sp, sp, -96\nsw ra, 92(sp)\nsw s0, 88(sp)\naddi s0, sp, 96\n"
.equ PROLOGUE_SIZE, . - prologue
epilogue: .ascii "lw ra, 92(sp)\nlw s0, 88(sp)\naddi sp, sp, 96\nret\n"
.equ EPILOGUE_SIZE, . - epilogue
asm_exit: .ascii "li a0, 0\nli a7, 93\necall\n"
.equ ASM_EXIT_SIZE, . - asm_exit
asm_start: .ascii ".type _start, @function\n_start:\n"
.equ ASM_START_SIZE, . - asm_start
asm_and_a0_a1: .ascii "and a0, a0, a1\n"
.equ ASM_AND_A0_A1_SIZE, . - asm_and_a0_a1
asm_or_a0_a1: .ascii "or a0, a0, a1\n"
.equ ASM_OR_A0_A1_SIZE, . - asm_or_a0_a1
asm_add_a0_a1: .ascii "add a0, a0, a1\n"
.equ ASM_ADD_A0_A1_SIZE, . - asm_add_a0_a1
asm_sub_a0_a1: .ascii "sub a0, a0, a1\n"
.equ ASM_SUB_A0_A1_SIZE, . - asm_sub_a0_a1
asm_mul_a0_a1: .ascii "mul a0, a0, a1\n"
.equ ASM_MUL_A0_A1_SIZE, . - asm_mul_a0_a1
asm_seqz_a0: .ascii "seqz a0, a0\n"
.equ ASM_SEQZ_A0_SIZE, . - asm_seqz_a0
asm_neg_a0: .ascii "neg a0, a0\n"
.equ ASM_NEG_A0_SIZE, . - asm_neg_a0
asm_type: .ascii ".type "
.equ ASM_TYPE_SIZE, . - asm_type
asm_type_function: .ascii ", @function\n"
.equ ASM_TYPE_FUNCTION_SIZE, . - asm_type_function
asm_type_object: .ascii ", @object\n"
.equ ASM_TYPE_OBJECT_SIZE, . - asm_type_object
asm_restore_parameters:
.ascii "lw a0, 60(sp)\nlw a1, 56(sp)\nlw a2, 52(sp)\nlw a3, 48(sp)\nlw a4, 44(sp)\nlw a5, 40(sp)\n"
.equ ASM_RESTORE_PARAMETERS_SIZE, . - asm_restore_parameters
asm_preserve_parameters:
.ascii "sw a0, 84(sp)\nsw a1, 80(sp)\nsw a2, 76(sp)\nsw a2, 76(sp)\nsw a3, 72(sp)\nsw a4, 68(sp)\nsw a5, 64(sp)\n"
.equ ASM_PRESERVE_PARAMETERS_SIZE, . - asm_preserve_parameters
.section .bss
.type source_code, @object
source_code: .zero SOURCE_BUFFER_SIZE
.section .text
# Ignores the import.
.type _compile_import, @function
_compile_import:
# Prologue.
addi sp, sp, -24
sw ra, 20(sp)
sw s0, 16(sp)
addi s0, sp, 24
.Lcompile_import_loop:
mv a0, s1
addi a1, sp, 0
call _tokenize_next
li t0, TOKEN_IMPORT
lw t1, 0(sp)
bne t0, t1, .Lcompile_import_end
# a0 is set from the previous _tokenize_next call. Skip the module name.
addi a1, sp, 0
call _tokenize_next
mv s1, a0
j .Lcompile_import_loop
.Lcompile_import_end:
# Epilogue.
lw ra, 20(sp)
lw s0, 16(sp)
addi sp, sp, 24
ret
.type _build_binary_expression, @function
_build_binary_expression:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
li a0, 0
call _build_expression
mv a0, s1
addi a1, sp, 12
call _tokenize_next
lw t0, 12(sp)
li t1, TOKEN_AND
beq t0, t1, .Lbuild_binary_expression_and
li t1, TOKEN_OR
beq t0, t1, .Lbuild_binary_expression_or
li t1, TOKEN_PLUS
beq t0, t1, .Lbuild_binary_expression_plus
li t1, TOKEN_EQUALS
beq t0, t1, .Lbuild_binary_expression_equal
li t1, TOKEN_ASTERISK
beq t0, t1, .Lbuild_binary_expression_product
li t1, TOKEN_MINUS
beq t0, t1, .Lbuild_binary_expression_minus
j .Lbuild_binary_expression_end
.Lbuild_binary_expression_equal:
mv s1, a0 # Skip =.
li a0, 1
call _build_expression
la a0, asm_sub_a0_a1
li a1, ASM_SUB_A0_A1_SIZE
call _write_out
la a0, asm_seqz_a0
li a1, ASM_SEQZ_A0_SIZE
call _write_out
j .Lbuild_binary_expression_end
.Lbuild_binary_expression_and:
mv s1, a0 # Skip &.
li a0, 1
call _build_expression
la a0, asm_and_a0_a1
li a1, ASM_AND_A0_A1_SIZE
call _write_out
j .Lbuild_binary_expression_end
.Lbuild_binary_expression_or:
mv s1, a0 # Skip or.
li a0, 1
call _build_expression
la a0, asm_or_a0_a1
li a1, ASM_OR_A0_A1_SIZE
call _write_out
j .Lbuild_binary_expression_end
.Lbuild_binary_expression_plus:
mv s1, a0 # Skip +.
li a0, 1
call _build_expression
la a0, asm_add_a0_a1
li a1, ASM_ADD_A0_A1_SIZE
call _write_out
j .Lbuild_binary_expression_end
.Lbuild_binary_expression_minus:
mv s1, a0 # Skip -.
li a0, 1
call _build_expression
la a0, asm_sub_a0_a1
li a1, ASM_SUB_A0_A1_SIZE
call _write_out
j .Lbuild_binary_expression_end
.Lbuild_binary_expression_product:
mv s1, a0 # Skip *.
li a0, 1
call _build_expression
la a0, asm_mul_a0_a1
li a1, ASM_MUL_A0_A1_SIZE
call _write_out
j .Lbuild_binary_expression_end
.Lbuild_binary_expression_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Checks whether the given identifier starts with "loca".
# Parameters:
# a0 - Pointer to the identifier.
# a1 - Identifier length.
#
# Sets a0 to 1 if the identifier starts with "loca", otherwise to 0.
.type _is_local_identifier, @function
_is_local_identifier:
# Prologue.
addi sp, sp, -16
sw ra, 12(sp)
sw s0, 8(sp)
addi s0, sp, 16
li t0, 0x61636f6c # loca
sw t0, 4(sp)
# a0 is already set.
addi a1, sp, 4
li a2, 4
call _memcmp
seqz a0, a0
# Epilogue.
lw ra, 12(sp)
lw s0, 8(sp)
addi sp, sp, 16
ret
# Checks whether the given identifier is a saved register name, like s1 or s2.
# Parameters:
# a0 - Pointer to the identifier.
# a1 - Identifier length.
#
# Sets a0 to 1 if the identifier is a preserved register, otherwise to 0.
.type _is_register_identifier, @function
_is_register_identifier:
# Prologue.
addi sp, sp, -8
sw ra, 4(sp)
sw s0, 0(sp)
addi s0, sp, 8
lbu a0, (a0)
addi a1, a1, -2
seqz a1, a1
addi t0, a0, -'s'
seqz t0, t0
and a0, a1, t0
# Epilogue.
lw ra, 4(sp)
lw s0, 0(sp)
addi sp, sp, 8
ret
# Parameters:
# a0 - Identifier length.
# a1 - Register number as character.
.type _compile_identifier_expression, @function
_compile_identifier_expression:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
sw a0, 20(sp) # Identifier length.
sw a1, 16(sp) # Register number as character.
mv a0, s1
lw a1, 20(sp)
call _is_local_identifier
bnez a0, .Lcompile_identifier_expression_local
mv a0, s1
lw a1, 20(sp)
call _is_register_identifier
bnez a0, .Lcompile_identifier_expression_saved
# Global identifier.
lw t1, 16(sp)
li t0, 0x00202c00 # \0,_
or t0, t0, t1
sw t0, 12(sp)
li t0, 0x6120616c # la a
sw t0, 8(sp)
addi a0, sp, 8
li a1, 7
call _write_out
mv a0, s1
lw a1, 20(sp)
call _write_out
li a0, '\n'
call _put_char
lbu a0, (s1)
call _is_upper
beqz a0, .Lcompile_identifier_expression_end
lw t1, 16(sp)
li t0, 0x0a290061 # a\0)\n
sll t2, t1, 8
or t0, t0, t2
sw t0, 12(sp)
li t0, 0x28202c00 # \0, (
or t0, t0, t1
sw t0, 8(sp)
li t0, 0x6120776c # lw a
sw t0, 4(sp)
addi a0, sp, 4
li a1, 12
call _write_out
j .Lcompile_identifier_expression_end
.Lcompile_identifier_expression_saved:
li t0, 0x00202c00 # \0,_
lw t1, 16(sp)
or t0, t0, t1
sw t0, 12(sp)
li t0, 0x6120766d # mv a
sw t0, 8(sp)
addi a0, sp, 8
li a1, 7
call _write_out
mv a0, s1
lw a1, 20(sp)
call _write_out
li a0, '\n'
call _put_char
j .Lcompile_identifier_expression_end
.Lcompile_identifier_expression_local:
lw t1, 16(sp)
li t0, 0x00202c00 # \0,_
or t0, t0, t1
sw t0, 12(sp)
li t0, 0x6120776c # lw a
sw t0, 8(sp)
addi a0, sp, 8
li a1, 7
call _write_out
mv a0, s1
lw a1, 20(sp)
addi a0, a0, 4 # Skip the "loca" variable prefix.
addi a1, a1, -4 # Skip the "loca" variable prefix.
call _write_out
li t0, 0x29707328 # (sp)
sw t0, 12(sp)
addi a0, sp, 12
li a1, 4
call _write_out
li a0, '\n'
call _put_char
j .Lcompile_identifier_expression_end
.Lcompile_identifier_expression_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Evalutes an expression and saves the result in a0.
#
# a0 - X in aX, the register number to save the result.
.type _build_expression, @function
_build_expression:
# Prologue.
addi sp, sp, -48
sw ra, 44(sp)
sw s0, 40(sp)
addi s0, sp, 48
addi a0, a0, '0' # Make the register number to a character.
sw a0, 36(sp) # And save it.
mv a0, s1
addi a1, sp, 24
call _tokenize_next
sw a0, 20(sp)
lw a0, 24(sp)
li t0, TOKEN_MINUS
beq a0, t0, .Lbuild_expression_negate
li t0, TOKEN_AT
beq a0, t0, .Lbuild_expression_address
li t0, TOKEN_INTEGER
beq a0, t0, .Lbuild_expression_literal
lw a0, 32(sp)
lbu a0, (a0)
li t0, '_'
beq a0, t0, .Lbuild_expression_call
lw s1, 32(sp)
lw a0, 28(sp)
lw a1, 36(sp)
call _compile_identifier_expression
j .Lbuild_expression_advance
.Lbuild_expression_negate:
lw s1, 20(sp) # Skip the -.
mv a0, zero
call _build_expression
la a0, asm_neg_a0
li a1, ASM_NEG_A0_SIZE
call _write_out
j .Lbuild_expression_end
.Lbuild_expression_address:
lw t1, 36(sp)
li t0, 0x20 # _
sw t0, 16(sp)
li t0, 0x2c707320 # _sp,
sw t0, 12(sp)
li t0, 0x2c006120 # _a\0,
sw t0, 8(sp)
sb t1, 10(sp)
li t0, 0x69646461 # addi
sw t0, 4(sp)
addi a0, sp, 4
li a1, 13
call _write_out
lw a0, 20(sp) # Skip @.
addi a1, sp, 24
call _tokenize_next
mv s1, a0
lw a0, 32(sp)
lw a1, 28(sp)
addi a0, a0, 4 # Skip the "loca" variable prefix.
addi a1, a1, -4 # Skip the "loca" variable prefix.
call _write_out
li a0, '\n'
call _put_char
j .Lbuild_expression_end
.Lbuild_expression_call:
lw a0, 20(sp)
addi a1, sp, 8
call _tokenize_next
mv s1, a0
lw a0, 32(sp)
lw a1, 28(sp)
call _compile_call
j .Lbuild_expression_end
.Lbuild_expression_literal:
lw t1, 36(sp)
li t0, 0x00202c00 # \0,_
or t0, t0, t1
sw t0, 16(sp)
li t0, 0x6120696c # li a
sw t0, 12(sp)
addi a0, sp, 12
li a1, 7
call _write_out
lw a0, 32(sp)
lw a1, 28(sp)
call _write_out
li a0, '\n'
call _put_char
j .Lbuild_expression_advance
.Lbuild_expression_advance:
lw s1, 20(sp)
.Lbuild_expression_end:
# Epilogue.
lw ra, 44(sp)
lw s0, 40(sp)
addi sp, sp, 48
ret
# Compiles an lvalue.
#
# Parameters:
# a0 - Pointer to the identifier.
# a1 - Identifier length.
.type _compile_designator_expression, @function
_compile_designator_expression:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
sw a0, 20(sp) # Identifier pointer.
sw a1, 16(sp) # Identifier length.
lw a0, 20(sp)
lw a1, 16(sp)
call _is_local_identifier
bnez a0, .Lcompile_designator_expression_local
lw a0, 20(sp)
lw a1, 16(sp)
call _is_register_identifier
bnez a0, .Lcompile_designator_expression_saved
.Lcompile_designator_expression_local:
li t0, 0x202c30 # 0,_
sw t0, 12(sp)
li t0, 0x61207773 # sw a
sw t0, 8(sp)
addi a0, sp, 8
li a1, 7
call _write_out
lw a0, 20(sp)
lw a1, 16(sp)
addi a0, a0, 4 # Skip the "loca" variable prefix.
addi a1, a1, -4 # Skip the "loca" variable prefix.
call _write_out
li t0, '\n'
sw t0, 12(sp)
li t0, 0x29707328 # (sp)
sw t0, 8(sp)
addi a0, sp, 8
li a1, 5
call _write_out
j .Lcompile_designator_expression_end
.Lcompile_designator_expression_saved:
li t0, 0x20766d # mv_
sw t0, 12(sp)
addi a0, sp, 12
li a1, 3
call _write_out
lw a0, 20(sp)
lw a1, 16(sp)
call _write_out
li t0, 0x0a # \n
sw t0, 12(sp)
li t0, 0x3061202c # , a0
sw t0, 8(sp)
addi a0, sp, 8
li a1, 5
call _write_out
j .Lcompile_designator_expression_end
.Lcompile_designator_expression_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Compiles a statement beginning with an identifier.
#
# Left values should be variables named "loca n", where n is the offset
# of the variable on the stack, like loca8 or loca4.
.type _compile_identifier, @function
_compile_identifier:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
# Save the pointer to the identifier and its length on the stack.
mv a0, s1
addi a1, sp, 12
call _tokenize_next
addi a1, sp, 0
call _tokenize_next
mv s1, a0
lw t0, 0(sp)
li t1, TOKEN_ASSIGN
beq t0, t1, .Lcompile_identifier_assign
li t1, TOKEN_LEFT_PAREN
beq t0, t1, .Lcompile_identifier_call
j .Lcompile_identifier_end
.Lcompile_identifier_call:
lw a0, 20(sp)
lw a1, 16(sp)
call _compile_call
j .Lcompile_identifier_end
.Lcompile_identifier_assign:
call _build_binary_expression
lw a0, 20(sp)
lw a1, 16(sp)
call _compile_designator_expression
j .Lcompile_identifier_end
.Lcompile_identifier_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Compiles a procedure call. Expects s1 to point to the first argument.
# a0 - Pointer to the procedure name.
# a1 - Length of the procedure name.
#
# Returns the procedure result in a0.
.type _compile_call, @function
_compile_call:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
sw a0, 20(sp)
sw a1, 16(sp)
sw zero, 12(sp) # Argument count for a procedure call.
.Lcompile_call_paren:
lbu t0, (s1)
li t1, 0x29 # )
beq t0, t1, .Lcompile_call_complete
.Lcompile_call_argument:
li a0, 0
call _build_expression
li t0, 0x202c30 # 0,_
sw t0, 8(sp)
li t0, 0x61207773 # sw a
sw t0, 4(sp)
addi a0, sp, 4
li a1, 7
call _write_out
lw t0, 12(sp) # Argument count for a procedure call.
# Only 6 arguments are supported with a0-a5.
# Save all arguments on the stack so they aren't overriden afterwards.
li a0, -4
mul a0, t0, a0
addi a0, a0, 60
call _printi
li t0, '\n'
sw t0, 8(sp)
li t0, 0x29707328 # (sp)
sw t0, 4(sp)
addi a0, sp, 4
li a1, 5
call _write_out
lbu t0, (s1)
li t1, ','
bne t0, t1, .Lcompile_call_paren
lw t0, 12(sp) # Argument count for a procedure call.
addi t0, t0, 1
sw t0, 12(sp)
addi s1, s1, 1 # Skip the comma between the arguments.
j .Lcompile_call_argument
.Lcompile_call_complete:
sw zero, 12(sp)
.Lcompile_call_restore:
# Just go through all a0-a5 registers and read them from stack.
# If this stack value contains garbage, the procedure just shouldn't use it.
la a0, asm_restore_parameters
li a1, ASM_RESTORE_PARAMETERS_SIZE
call _write_out
.Lcompile_call_perform:
li t0, 0x20
sw t0, 8(sp)
li t0, 0x6c6c6163 # call
sw t0, 4(sp)
addi a0, sp, 4
li a1, 5
call _write_out
lw a0, 20(sp)
lw a1, 16(sp)
call _write_out
li a0, '\n'
call _put_char
addi s1, s1, 1 # Skip the close paren.
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Walks through the procedure definitions.
.type _compile_procedure_section, @function
_compile_procedure_section:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
.Lcompile_procedure_section_loop:
mv a0, s1
addi a1, sp, 4
call _tokenize_next
li t0, TOKEN_PROC
lw t1, 4(sp)
bne t0, t1, .Lcompile_procedure_section_end
call _compile_procedure
j .Lcompile_procedure_section_loop
.Lcompile_procedure_section_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
.type _compile_module_declaration, @function
_compile_module_declaration:
# Prologue.
addi sp, sp, -24
sw ra, 20(sp)
sw s0, 16(sp)
addi s0, sp, 24
la a0, global_start
li a1, GLOBAL_START_SIZE
call _write_out
# Skip "program".
mv a0, s1
addi a1, sp, 4
call _tokenize_next
mv s1, a0
# Epilogue.
lw ra, 20(sp)
lw s0, 16(sp)
addi sp, sp, 24
ret
.type _compile_constant_section, @function
_compile_constant_section:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 4
call _tokenize_next
li t0, TOKEN_CONST
lw t1, 4(sp)
bne t0, t1, .Lcompile_constant_section_end
mv s1, a0
la a0, section_rodata
li a1, SECTION_RODATA_SIZE
call _write_out
.Lcompile_constant_section_item:
mv a0, s1
addi a1, sp, 12
call _tokenize_next
lw t0, 12(sp)
li t1, TOKEN_IDENTIFIER
bne t0, t1, .Lcompile_constant_section_end
lw s1, 20(sp)
call _compile_constant
j .Lcompile_constant_section_item
.Lcompile_constant_section_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
.type _compile_constant, @function
_compile_constant:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 12
call _tokenize_next
addi a1, sp, 0
call _tokenize_next # Skip the assignment sign.
mv s1, a0
# Write identifier the identifier.
lw a0, 20(sp)
lw a1, 16(sp)
call _write_out
# : .long
li t0, 0x20676e6f # ong_
sw t0, 4(sp)
li t0, 0x6c2e203a # : .l
sw t0, 0(sp)
mv a0, sp
li a1, 8
call _write_out
mv a0, s1
addi a1, sp, 12
call _tokenize_next
mv s1, a0
lw a0, 20(sp) # Save the literal pointer before advancing it.
lw a1, 16(sp) # The literal length.
call _write_out
li a0, '\n'
call _put_char
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
.type _compile_variable_section, @function
_compile_variable_section:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 4
call _tokenize_next
li t0, TOKEN_VAR
lw t1, 4(sp)
bne t0, t1, .Lcompile_variable_section_end
mv s1, a0
la a0, section_bss
li a1, SECTION_BSS_SIZE
call _write_out
.Lcompile_variable_section_item:
mv a0, s1
addi a1, sp, 12
call _tokenize_next
lw t0, 12(sp)
li t1, TOKEN_IDENTIFIER
bne t0, t1, .Lcompile_variable_section_end
lw s1, 20(sp) # Advance to the beginning of the variable name.
call _compile_variable
j .Lcompile_variable_section_item
.Lcompile_variable_section_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Compile a global variable.
.type _compile_variable, @function
_compile_variable:
# Prologue.
addi sp, sp, -48
sw ra, 44(sp)
sw s0, 40(sp)
addi s0, sp, 48
# Save the identifier on the stack since it should emitted multiple times.
mv a0, s1
addi a1, sp, 28
call _tokenize_next
addi a1, sp, 4
call _tokenize_next # Skip the colon in front of the type.
addi a1, sp, 4
call _tokenize_next # Skip the opening bracket.
addi a1, sp, 16
call _tokenize_next # Save the array size on the stack since it has to be emitted multiple times.
addi a1, sp, 4
call _tokenize_next # Skip the closing bracket.
addi a1, sp, 4
call _tokenize_next # Skip the type.
mv s1, a0
# .type identifier, @object
la a0, asm_type
li a1, ASM_TYPE_SIZE
call _write_out
lw a0, 36(sp)
lw a1, 32(sp)
call _write_out
la a0, asm_type_object
li a1, ASM_TYPE_OBJECT_SIZE
call _write_out
# identifier: .zero size
lw a0, 36(sp)
lw a1, 32(sp)
call _write_out
li t0, 0x206f7265 # ero_
sw t0, 12(sp)
li t0, 0x7a2e203a # : .z
sw t0, 8(sp)
addi a0, sp, 8
li a1, 8
call _write_out
lw a0, 24(sp)
lw a1, 20(sp)
call _write_out
li a0, '\n'
call _put_char
# Epilogue.
lw ra, 44(sp)
lw s0, 40(sp)
addi sp, sp, 48
ret
.type _compile_type_expression, @function
_compile_type_expression:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
.Lcompile_type_expression_type:
mv a0, s1
addi a1, sp, 12
call _tokenize_next
mv s1, a0
lw t0, 12(sp)
# Skip the pointer designator and handle the rest of the type.
li t1, TOKEN_HAT
beq t0, t1, .Lcompile_type_expression_type
/* DEBUG */
lw a0, 20(sp)
lw a1, 16(sp)
call _write_error
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
.type _compile_parameters, @function
_compile_parameters:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 12
call _tokenize_next
mv s1, a0 # Skip the opening paren.
mv a0, s1
addi a1, sp, 12
call _tokenize_next
lw t0, 12(sp)
li t1, TOKEN_RIGHT_PAREN
beq t0, t1, .Lcompile_parameters_end
# When this is not the right paren, it is an identifier.
mv s1, a0
.Lcompile_parameters_parameter:
mv a0, s1
addi a1, sp, 0
call _tokenize_next
mv s1, a0 # Skip the ":" in front of the type.
call _compile_type_expression
# Read the comma between the parameters or a closing paren.
mv a0, s1
addi a1, sp, 0
call _tokenize_next
lw t0, 0(sp)
li t1, TOKEN_COMMA
bne t0, t1, .Lcompile_parameters_end
# If it is a comma, read the name of the next parameter.
addi a1, sp, 12
call _tokenize_next
mv s1, a0
j .Lcompile_parameters_parameter
.Lcompile_parameters_end:
mv s1, a0 # Skip the closing paren.
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
.type _compile_procedure, @function
_compile_procedure:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 12
call _tokenize_next # Skip proc.
addi a1, sp, 12
call _tokenize_next
mv s1, a0
lw a0, 16(sp)
lw a1, 20(sp)
call _write_procedure_head
call _compile_parameters
# Skip all declarations until we find the "begin" keyword, denoting the
# beginning of the procedure body.
.Lcompile_procedure_begin:
mv a0, s1
addi a1, sp, 4
call _tokenize_next
mv s1, a0
lw t0, 4(sp)
li t1, TOKEN_BEGIN
bne t0, t1, .Lcompile_procedure_begin
# Generate the procedure prologue with a predefined stack size.
la a0, prologue
li a1, PROLOGUE_SIZE
call _write_out
# Save passed arguments on the stack.
la a0, asm_preserve_parameters
li a1, ASM_PRESERVE_PARAMETERS_SIZE
call _write_out
# Generate the body of the procedure.
call _compile_statements
mv s1, a0 # Skip end.
# Generate the procedure epilogue with a predefined stack size.
la a0, epilogue
li a1, EPILOGUE_SIZE
call _write_out
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Compiles a goto statement to an uncoditional jump.
.type _compile_goto, @function
_compile_goto:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 0
call _tokenize_next # Skip the goto keyword.
addi a1, sp, 0
call _tokenize_next # We should be on dot the label is beginning with.
addi a1, sp, 0
call _tokenize_next# Save the label name.
mv s1, a0
li t0, 0x2e206a # j .
sw t0, 12(sp)
addi a0, sp, 12
li a1, 3
call _write_out
lw a0, 8(sp) # Saved dot position.
lw a1, 4(sp)
call _write_out
li a0, '\n'
call _put_char
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Rewrites a label to assembly.
.type _compile_label, @function
_compile_label:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 8
call _tokenize_next # Dot starting the label.
addi a1, sp, 8
call _tokenize_next
mv s1, a0
li a0, '.'
call _put_char
lw a0, 16(sp)
lw a1, 12(sp)
call _write_out
li a0, ':'
call _put_char
li a0, '\n'
call _put_char
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Just skips the return keyword and evaluates the return expression.
.type _compile_return, @function
_compile_return:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 12
call _tokenize_next
mv s1, a0 # Skip return.
call _build_binary_expression
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
.type _compile_if, @function
_compile_if:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 0
call _tokenize_next
mv s1, a0 # Skip the if.
call _build_binary_expression
mv a0, s1
addi a1, sp, 0
call _tokenize_next
mv s1, a0 # Skip the then.
# Label prefix.
li t0, 0x66694c2e # .Lif
sw t0, 20(sp)
li t0, 0x202c3061 # a0,_
sw t0, 16(sp)
li t0, 0x207a7165 # eqz_
sw t0, 12(sp)
li t0, 0x62626262 # bbbb
sb t0, 11(sp)
addi a0, sp, 11
li a1, 13
call _write_out
# Write the label counter.
mv a0, s2
call _printi
li a0, '\n'
call _put_char
call _compile_statements
mv s1, a0 # Skip end.
# Write the label prefix.
addi a0, sp, 20
li a1, 4
call _write_out
# Write the label counter.
mv a0, s2
call _printi
# Finalize the label.
li t0, 0x0a3a # :\n
sh t0, 16(sp)
addi a0, sp, 16
li a1, 2
call _write_out
addi s2, s2, 1 # Increment the label counter.
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Writes:
# .type identifier, @function
# identifier:
#
# Parameters:
# a0 - Identifier length.
# a0 - Identifier pointer.
.type _write_procedure_head, @function
_write_procedure_head:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
sw a0, 16(sp)
sw a1, 20(sp)
# .type identifier, @function
la a0, asm_type
li a1, ASM_TYPE_SIZE
call _write_out
lw a0, 20(sp)
lw a1, 16(sp)
call _write_out
la a0, asm_type_function
li a1, ASM_TYPE_FUNCTION_SIZE
call _write_out
lw a0, 20(sp)
lw a1, 16(sp)
call _write_out
li t0, 0x0a3a # :\n
sw t0, 12(sp)
addi a0, sp, 12
li a1, 2
call _write_out
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Compiles a list of statements delimited by semicolons.
#
# Sets a0 to the end of the token finishing the list
# (should be the "end" token in a valid program).
.type _compile_statements, @function
_compile_statements:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
# Generate the body of the procedure.
mv a0, s1
addi a1, sp, 0
call _tokenize_next
lw t0, 0(sp)
li t1, TOKEN_END
beq t0, t1, .Lcompile_statements_end
.Lcompile_statements_body:
call _compile_statement
mv a0, s1
addi a1, sp, 0
call _tokenize_next
lw t0, 0(sp)
li t1, TOKEN_SEMICOLON
bne t0, t1, .Lcompile_statements_end
mv s1, a0
j .Lcompile_statements_body
.Lcompile_statements_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Checks for the type of the current statement and compiles it.
.type _compile_statement, @function
_compile_statement:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
mv a0, s1
addi a1, sp, 0
call _tokenize_next
lw t0, 0(sp)
li t1, TOKEN_IDENTIFIER
beq t0, t1, .Lcompile_statement_identifier
li t1, TOKEN_GOTO
beq t0, t1, .Lcompile_statement_goto
li t1, TOKEN_RETURN
beq t0, t1, .Lcompile_statement_return
li t1, TOKEN_IF
beq t0, t1, .Lcompile_statement_if
li t1, TOKEN_DOT
beq t0, t1, .Lcompile_statement_label
unimp # Else.
.Lcompile_statement_if:
call _compile_if
j .Lcompile_statement_end
.Lcompile_statement_label:
call _compile_label
j .Lcompile_statement_end
.Lcompile_statement_return:
call _compile_return
j .Lcompile_statement_end
.Lcompile_statement_goto:
call _compile_goto
j .Lcompile_statement_end
.Lcompile_statement_identifier:
call _compile_identifier
j .Lcompile_statement_end
.Lcompile_statement_end:
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
# Prints ".section .text" and exits.
.type _compile_text_section, @function
_compile_text_section:
# Prologue.
addi sp, sp, -16
sw ra, 12(sp)
sw s0, 8(sp)
addi s0, sp, 16
la a0, section_text
li a1, SECTION_TEXT_SIZE
call _write_out
# Epilogue.
lw ra, 12(sp)
lw s0, 8(sp)
addi sp, sp, 16
ret
.type _compile_entry_point, @function
_compile_entry_point:
# Prologue.
addi sp, sp, -32
sw ra, 28(sp)
sw s0, 24(sp)
addi s0, sp, 32
# .type _start, @function
la a0, asm_start
li a1, ASM_START_SIZE
call _write_out
mv a0, s1
addi a1, sp, 4
call _tokenize_next
mv s1, a0 # Skip begin.
# Generate the body of the procedure.
call _compile_statements
mv s1, a0 # Skip end.
la a0, asm_exit
li a1, ASM_EXIT_SIZE
call _write_out
# Epilogue.
lw ra, 28(sp)
lw s0, 24(sp)
addi sp, sp, 32
ret
.type _compile, @function
_compile:
# Prologue.
addi sp, sp, -16
sw ra, 12(sp)
sw s0, 8(sp)
addi s0, sp, 16
call _compile_module_declaration
call _compile_import
call _compile_constant_section
call _compile_variable_section
call _compile_text_section
call _compile_procedure_section
call _compile_entry_point
# Epilogue.
lw ra, 12(sp)
lw s0, 8(sp)
addi sp, sp, 16
ret
# Entry point.
.type _start, @function
_start:
# Read the source from the standard input.
la a0, source_code
li a1, SOURCE_BUFFER_SIZE # Buffer size.
call _read_file
li s2, 1
call symbol_table_build
call _compile
# Call exit.
li a0, 0 # Use 0 return code.
call _exit