Parse procedure parameters

2 files changed, 150 insertions, 17 deletions

diff --git a/boot/stage1.s b/boot/stage1.s
index b39f5bc..efbd521 100644
--- a/boot/stage1.s
+++ b/boot/stage1.s
@@ -989,6 +989,90 @@ _compile_variable:
 	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.
@@ -1008,6 +1092,7 @@ _compile_procedure:
 	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:
@@ -1033,22 +1118,6 @@ _compile_procedure:
 	call _compile_statements
 	mv s1, a0 # Skip end.
 
-	/* DEBUG
-	sw a0, 8(sp)
-	lw a1, 12(sp)
-	li a2, TOKEN_END
-	sub a1, a1, a2
-	seqz a1, a1
-	seqz a0, a0
-	addi a0, a0, '0'
-	addi a1, a1, '0'
-	sb a0, 4(sp)
-	sb a1, 5(sp)
-	addi a0, sp, 4
-	li a1, 2
-	call _write_error
-	lw a0, 8(sp) */
-
 	# Generate the procedure epilogue with a predefined stack size.
 	la a0, epilogue
 	li a1, EPILOGUE_SIZE
diff --git a/boot/symbol.s b/boot/symbol.s
index 66409aa..a927b0e 100644
--- a/boot/symbol.s
+++ b/boot/symbol.s
@@ -2,7 +2,7 @@
 # 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 symbol_table_build
+.global symbol_table_build, symbol_table_find
 
 .include "boot/definitions.inc"
 
@@ -49,6 +49,70 @@ symbol_table: .zero SYMBOL_PRIME
 
 .section .text
 
+# Searches for a symbol by name.
+#
+# Parameters:
+# a0 - Local symbol table or 0.
+# a1 - Length of the symbol to search.
+# a2 - Pointer to the symbol name.
+#
+# Sets a0 to the symbol info.
+.type symbol_table_find, @function
+symbol_table_find:
+	# Prologue.
+	addi sp, sp, -32
+	sw ra, 28(sp)
+	sw s0, 24(sp)
+	addi s0, sp, 32
+
+	sw s1, 20(sp) # Current symbol in the table.
+	sw s2, 16(sp) # Symbol table length.
+	sw s3, 12(sp) # Length of the symbol to search.
+	sw s4, 8(sp) # Pointer to the symbol to search.
+
+	mv s3, a1
+	mv s4, a2
+
+	la s1, symbol_table
+	lw s2, 0(s1)
+	addi s1, s1, 4 # Advance to the first symbol in the table.
+
+.Lsymbol_table_find_loop:
+	beqz s2, .Lsymbol_table_find_not_found
+
+	# Compare string lengths.
+	lw a2, 0(s1)
+	bne s3, a2, .Lsymbol_table_find_continue
+
+	# If lengths match, compare the content.
+	mv a0, s4
+	lw a1, 4(s1)
+	call _memcmp
+
+	bnez a0, .Lsymbol_table_find_continue
+
+	lw a0, 8(s1) # Pointer to the symbol.
+	j .Lsymbol_table_end
+
+.Lsymbol_table_find_continue:
+	addi s2, s2, -1
+	j .Lsymbol_table_find_loop
+
+.Lsymbol_table_find_not_found:
+	li a0, 0
+
+.Lsymbol_table_end:
+	lw s1, 20(sp)
+	lw s2, 16(sp)
+	lw s3, 12(sp)
+	lw s4, 8(sp)
+
+	# Epilogue.
+	lw ra, 28(sp)
+	lw s0, 24(sp)
+	addi sp, sp, 32
+	ret
+
 # Build the initial symbols.
 #
 # Sets a0 to the pointer to the global symbol table.