The input code:
 
-- turn on tokens and semantic stack
-- examine the existing "writeln(x);" and the new
-- phase 2 writlne with strings and expressions
%%t
%%ss
x:=2;
writeln(x);
writeln(" ""hi"" there"," x = ",x);
-------------------------------------- 
 
Running SIMPLE
with command line -i (AST) -s (SymbolTable dump) -v (var addrs)
in     simple.c
grammar: stmtlist -> lambda

Token  : Id
grammar: identifier->Id 
After  : PushId Semstack is:
	 IdEntry (x)	<+ SemTop
	 StLstEntry
grammar: memref   -> identifier
After  : IdToAddr Semstack is:
	 AddrEntry 	<+ SemTop
	 StLstEntry

Token  : Assignop

Token  : Iconst
grammar: integer_const-> Iconst
After  : PushInt Semstack is:
	 IconstEntry	<+ SemTop
	 AddrEntry 
	 StLstEntry
grammar: primary  -> integer_const
After  : IconstReduce Semstack is:
	 ExprEntry 	<+ SemTop
	 AddrEntry 
	 StLstEntry
grammar: fact     -> primary
grammar: term     -> fact

Token  : Termsym
grammar: expr     -> term
grammar: assignstmt->memeref Assignop expr
After  : Assign Semstack is:
	 StmtEntry 	<+ SemTop
	 StLstEntry
grammar: stmt     -> assignstmt Termsym
grammar: stmtlist -> stmtlist stmt
After  : MergeStmts Semstack is:
	 StLstEntry	<+ SemTop

Token  : Writeln

Token  : Lparen

Token  : Id
grammar: identifier->Id 
After  : PushId Semstack is:
	 IdEntry (x)	<+ SemTop
	 StLstEntry
grammar: memref   -> identifier
After  : IdToAddr Semstack is:
	 AddrEntry 	<+ SemTop
	 StLstEntry
grammar: primary  -> memref
After  : AddrToPrimary Semstack is:
	 ExprEntry 	<+ SemTop
	 StLstEntry
grammar: fact     -> primary
grammar: term     -> fact

Token  : Rparen
grammar: expr     -> term
grammar: actparam  -> expr
After  : CreateActParam Semstack is:
	 ParmEntry 	<+ SemTop
	 StLstEntry
grammar: actparamlist->actparam
grammar: writestmt-> Writeln Lparen actparamlist Rparen
After  : Call Semstack is:
	 StmtEntry 	<+ SemTop
	 StLstEntry

Token  : Termsym
grammar: stmt     -> writestmt Termsym
grammar: stmtlist -> stmtlist stmt
After  : MergeStmts Semstack is:
	 StLstEntry	<+ SemTop

Token  : Writeln

Token  : Lparen

Token  : StrConst
grammar: actparam  -> StrConst
After  : PushString Semstack is:
	 StrEntry ( \"hi\" there)	<+ SemTop
	 StLstEntry
After  : CreateActParam Semstack is:
	 ParmEntry 	<+ SemTop
	 StLstEntry
grammar: actparamlist->actparam

Token  : Commasym

Token  : StrConst
grammar: actparam  -> StrConst
After  : PushString Semstack is:
	 StrEntry ( x = )	<+ SemTop
	 ParmEntry 
	 StLstEntry
After  : CreateActParam Semstack is:
	 ParmEntry 	<+ SemTop
	 ParmEntry 
	 StLstEntry
grammar: actparamlist->actparamlist Commasym actparam
After  : MergeActParam Semstack is:
	 ParmEntry 	<+ SemTop
	 StLstEntry

Token  : Commasym

Token  : Id
grammar: identifier->Id 
After  : PushId Semstack is:
	 IdEntry (x)	<+ SemTop
	 ParmEntry 
	 StLstEntry
grammar: memref   -> identifier
After  : IdToAddr Semstack is:
	 AddrEntry 	<+ SemTop
	 ParmEntry 
	 StLstEntry
grammar: primary  -> memref
After  : AddrToPrimary Semstack is:
	 ExprEntry 	<+ SemTop
	 ParmEntry 
	 StLstEntry
grammar: fact     -> primary
grammar: term     -> fact

Token  : Rparen
grammar: expr     -> term
grammar: actparam  -> expr
After  : CreateActParam Semstack is:
	 ParmEntry 	<+ SemTop
	 ParmEntry 
	 StLstEntry
grammar: actparamlist->actparamlist Commasym actparam
After  : MergeActParam Semstack is:
	 ParmEntry 	<+ SemTop
	 StLstEntry
grammar: writestmt-> Writeln Lparen actparamlist Rparen
After  : Call Semstack is:
	 StmtEntry 	<+ SemTop
	 StLstEntry

Token  : Termsym
grammar: stmt     -> writestmt Termsym
grammar: stmtlist -> stmtlist stmt
After  : MergeStmts Semstack is:
	 StLstEntry	<+ SemTop
grammar: program  -> stmtlist
After  : Done Semstack is:
		EMPTY
 
Symbol table dump:
  x
 
Intermediate Representation - the Abstract Syntax Tree
   Statements
      Assign
         x
            gets
         Immediate Value 2
      Writeln
         parameters
            x
      Writeln
         parameters
             \"hi\" these
             x = 
            x


From codegen.c - DisplayRegs() marks used registers

Register: 0 1 2 3 4 5 6 7 8 9 
          - - - - - - - - - - 
Used = x:                    


Variable dump from GenStorage 
ID: x           	Offset:     0	Proc. Level: 0
COMPILATION COMPLETE
out    simple.c
-------------------------------------
 
The listing file produced by simple
 
-- turn on tokens and semantic stack
-- examine the existing "writeln(x);" and the new
-- phase 2 writlne with strings and expressions
%%t
%%ss
x:=2;
writeln(x);
writeln(" ""hi"" there"," x = ",x);
-------------------------------------
 
The assembler file produced by simple
 
# Register Usage:
#     $s0 for global variables
#
	.text 
 	.globl main 
 main:
	la	$t9, CONST
	la	$s0, GVARS
#
# Start Code
# 
# Generate Assignment Statement 
	li	$t0,2
	sw	$t0,0($s0)
# 
# Generate Writeln statement 
	li	$v0, 1
	lw 	$a0,0($s0)
	syscall
	la	$a0, S0
	li	$v0, 4
	syscall

# 
# Generate Writeln statement 
	la	$a0, S2
	li	$v0, 4
	syscall
	la	$a0, S1
	li	$v0, 4
	syscall
	li	$v0, 1
	lw 	$a0,0($s0)
	syscall
	la	$a0, S0
	li	$v0, 4
	syscall

#
# Halt execution
	li	$v0 10
	syscall

#
# Finish up by writing out constants 
	.word 0
CONST:		#Constant storage area
	.data
S0:	.asciiz	"\n"
	.data
S1:	.asciiz	" x = "
	.data
S2:	.asciiz	" \"hi\" there"
#
# Reserve space for global variables
	.word 0
GVARS:		# space for Global Variables
	.data
_x:	.word 0	# Offset at 0
	.data
Temp_Wr:
	.word 0 #just for alignment of write(exprtree)
-------------------------------------
 
execute the code in spim:
 
SPIM Version 6.2 of January 11, 1999
Copyright 1990-1998 by James R. Larus (larus@cs.wisc.edu).
All Rights Reserved.
See the file README for a full copyright notice.
Loaded: /opt/spim/bin/trap.handler
2
 "hi" there x = 2