add a new BF->LLVM translator, contributed by Sterling Stein.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41881 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2007-09-12 18:24:00 +00:00
parent 36597a5ddb
commit bef8e0b0a7
5 changed files with 721 additions and 1 deletions

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examples/BrainF/BrainF.cpp Normal file
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//===-- BrainF.cpp - BrainF compiler example ----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Sterling Stein and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===--------------------------------------------------------------------===//
//
// This class compiles the BrainF language into LLVM assembly.
//
// The BrainF language has 8 commands:
// Command Equivalent C Action
// ------- ------------ ------
// , *h=getchar(); Read a character from stdin, 255 on EOF
// . putchar(*h); Write a character to stdout
// - --*h; Decrement tape
// + ++*h; Increment tape
// < --h; Move head left
// > ++h; Move head right
// [ while(*h) { Start loop
// ] } End loop
//
//===--------------------------------------------------------------------===//
#include "BrainF.h"
#include "llvm/Constants.h"
#include "llvm/ADT/STLExtras.h"
using namespace llvm;
//Set the constants for naming
const char *BrainF::tapereg = "tape";
const char *BrainF::headreg = "head";
const char *BrainF::label = "brainf";
const char *BrainF::testreg = "test";
Module *BrainF::parse(std::istream *in1, int mem, CompileFlags cf) {
in = in1;
memtotal = mem;
comflag = cf;
header();
readloop(0, 0, 0);
delete builder;
return module;
}
void BrainF::header() {
module = new Module("BrainF");
//Function prototypes
//declare void @llvm.memset.i32(i8 *, i8, i32, i32)
Function *memset_func = cast<Function>(module->
getOrInsertFunction("llvm.memset.i32", Type::VoidTy,
PointerType::get(IntegerType::Int8Ty),
IntegerType::Int8Ty, IntegerType::Int32Ty,
IntegerType::Int32Ty, NULL));
//declare i32 @getchar()
getchar_func = cast<Function>(module->
getOrInsertFunction("getchar", IntegerType::Int32Ty, NULL));
//declare i32 @putchar(i32)
putchar_func = cast<Function>(module->
getOrInsertFunction("putchar", IntegerType::Int32Ty,
IntegerType::Int32Ty, NULL));
//Function header
//define void @brainf()
brainf_func = cast<Function>(module->
getOrInsertFunction("brainf", Type::VoidTy, NULL));
builder = new LLVMBuilder(new BasicBlock(label, brainf_func));
//%arr = malloc i8, i32 %d
ConstantInt *val_mem = ConstantInt::get(APInt(32, memtotal));
ptr_arr = builder->CreateMalloc(IntegerType::Int8Ty, val_mem, "arr");
//call void @llvm.memset.i32(i8 *%arr, i8 0, i32 %d, i32 1)
{
Value *memset_params[] = {
ptr_arr,
ConstantInt::get(APInt(8, 0)),
val_mem,
ConstantInt::get(APInt(32, 1))
};
CallInst *memset_call = builder->
CreateCall(memset_func, memset_params, array_endof(memset_params));
memset_call->setTailCall(false);
}
//%arrmax = getelementptr i8 *%arr, i32 %d
if (comflag & flag_arraybounds) {
ptr_arrmax = builder->
CreateGEP(ptr_arr, ConstantInt::get(APInt(32, memtotal)), "arrmax");
}
//%head.%d = getelementptr i8 *%arr, i32 %d
curhead = builder->CreateGEP(ptr_arr,
ConstantInt::get(APInt(32, memtotal/2)),
headreg);
//Function footer
//brainf.end:
endbb = new BasicBlock(label, brainf_func);
//free i8 *%arr
new FreeInst(ptr_arr, endbb);
//ret void
new ReturnInst(endbb);
//Error block for array out of bounds
if (comflag & flag_arraybounds)
{
//@aberrormsg = internal constant [%d x i8] c"\00"
Constant *msg_0 = ConstantArray::
get("Error: The head has left the tape.", true);
GlobalVariable *aberrormsg = new GlobalVariable(
msg_0->getType(),
true,
GlobalValue::InternalLinkage,
msg_0,
"aberrormsg",
module);
//declare i32 @puts(i8 *)
Function *puts_func = cast<Function>(module->
getOrInsertFunction("puts", IntegerType::Int32Ty,
PointerType::get(IntegerType::Int8Ty), NULL));
//brainf.aberror:
aberrorbb = new BasicBlock(label, brainf_func);
//call i32 @puts(i8 *getelementptr([%d x i8] *@aberrormsg, i32 0, i32 0))
{
Constant *zero_32 = Constant::getNullValue(IntegerType::Int32Ty);
Constant *gep_params[] = {
zero_32,
zero_32
};
Constant *msgptr = ConstantExpr::
getGetElementPtr(aberrormsg, gep_params,
array_lengthof(gep_params));
Value *puts_params[] = {
msgptr
};
CallInst *puts_call =
new CallInst(puts_func,
puts_params, array_endof(puts_params),
"", aberrorbb);
puts_call->setTailCall(false);
}
//br label %brainf.end
new BranchInst(endbb, aberrorbb);
}
}
void BrainF::readloop(PHINode *phi, BasicBlock *oldbb, BasicBlock *testbb) {
Symbol cursym = SYM_NONE;
int curvalue = 0;
Symbol nextsym = SYM_NONE;
int nextvalue = 0;
char c;
int loop;
int direction;
while(cursym != SYM_EOF && cursym != SYM_ENDLOOP) {
// Write out commands
switch(cursym) {
case SYM_NONE:
// Do nothing
break;
case SYM_READ:
{
//%tape.%d = call i32 @getchar()
CallInst *getchar_call = builder->CreateCall(getchar_func, tapereg);
getchar_call->setTailCall(false);
Value *tape_0 = getchar_call;
//%tape.%d = trunc i32 %tape.%d to i8
TruncInst *tape_1 = builder->
CreateTrunc(tape_0, IntegerType::Int8Ty, tapereg);
//store i8 %tape.%d, i8 *%head.%d
builder->CreateStore(tape_1, curhead);
}
break;
case SYM_WRITE:
{
//%tape.%d = load i8 *%head.%d
LoadInst *tape_0 = builder->CreateLoad(curhead, tapereg);
//%tape.%d = sext i8 %tape.%d to i32
SExtInst *tape_1 = builder->
CreateSExt(tape_0, IntegerType::Int32Ty, tapereg);
//call i32 @putchar(i32 %tape.%d)
Value *putchar_params[] = {
tape_1
};
CallInst *putchar_call = builder->
CreateCall(putchar_func,
putchar_params, array_endof(putchar_params));
putchar_call->setTailCall(false);
}
break;
case SYM_MOVE:
{
//%head.%d = getelementptr i8 *%head.%d, i32 %d
curhead = builder->
CreateGEP(curhead, ConstantInt::get(APInt(32, curvalue)),
headreg);
//Error block for array out of bounds
if (comflag & flag_arraybounds)
{
//%test.%d = icmp uge i8 *%head.%d, %arrmax
ICmpInst *test_0 = builder->
CreateICmpUGE(curhead, ptr_arrmax, testreg);
//%test.%d = icmp ult i8 *%head.%d, %arr
ICmpInst *test_1 = builder->
CreateICmpULT(curhead, ptr_arr, testreg);
//%test.%d = or i1 %test.%d, %test.%d
BinaryOperator *test_2 = builder->
CreateOr(test_0, test_1, testreg);
//br i1 %test.%d, label %main.%d, label %main.%d
BasicBlock *nextbb = new BasicBlock(label, brainf_func);
builder->CreateCondBr(test_2, aberrorbb, nextbb);
//main.%d:
builder->SetInsertPoint(nextbb);
}
}
break;
case SYM_CHANGE:
{
//%tape.%d = load i8 *%head.%d
LoadInst *tape_0 = builder->CreateLoad(curhead, tapereg);
//%tape.%d = add i8 %tape.%d, %d
BinaryOperator *tape_1 = builder->
CreateAdd(tape_0, ConstantInt::get(APInt(8, curvalue)), tapereg);
//store i8 %tape.%d, i8 *%head.%d\n"
builder->CreateStore(tape_1, curhead);
}
break;
case SYM_LOOP:
{
//br label %main.%d
BasicBlock *testbb = new BasicBlock(label, brainf_func);
builder->CreateBr(testbb);
//main.%d:
BasicBlock *bb_0 = builder->GetInsertBlock();
BasicBlock *bb_1 = new BasicBlock(label, brainf_func);
builder->SetInsertPoint(bb_1);
//Make part of PHI instruction now, wait until end of loop to finish
PHINode *phi_0 = new PHINode(PointerType::get(IntegerType::Int8Ty),
headreg, testbb);
phi_0->reserveOperandSpace(2);
phi_0->addIncoming(curhead, bb_0);
curhead = phi_0;
readloop(phi_0, bb_1, testbb);
}
break;
default:
cerr<<"Error: Unknown symbol.\n";
abort();
break;
}
cursym = nextsym;
curvalue = nextvalue;
nextsym = SYM_NONE;
// Reading stdin loop
loop = (cursym == SYM_NONE)
|| (cursym == SYM_MOVE)
|| (cursym == SYM_CHANGE);
while(loop) {
*in>>c;
if (in->eof()) {
if (cursym == SYM_NONE) {
cursym = SYM_EOF;
} else {
nextsym = SYM_EOF;
}
loop = 0;
} else {
direction = 1;
switch(c) {
case '-':
direction = -1;
// Fall through
case '+':
if (cursym == SYM_CHANGE) {
curvalue += direction;
// loop = 1
} else {
if (cursym == SYM_NONE) {
cursym = SYM_CHANGE;
curvalue = direction;
// loop = 1
} else {
nextsym = SYM_CHANGE;
nextvalue = direction;
loop = 0;
}
}
break;
case '<':
direction = -1;
// Fall through
case '>':
if (cursym == SYM_MOVE) {
curvalue += direction;
// loop = 1
} else {
if (cursym == SYM_NONE) {
cursym = SYM_MOVE;
curvalue = direction;
// loop = 1
} else {
nextsym = SYM_MOVE;
nextvalue = direction;
loop = 0;
}
}
break;
case ',':
if (cursym == SYM_NONE) {
cursym = SYM_READ;
} else {
nextsym = SYM_READ;
}
loop = 0;
break;
case '.':
if (cursym == SYM_NONE) {
cursym = SYM_WRITE;
} else {
nextsym = SYM_WRITE;
}
loop = 0;
break;
case '[':
if (cursym == SYM_NONE) {
cursym = SYM_LOOP;
} else {
nextsym = SYM_LOOP;
}
loop = 0;
break;
case ']':
if (cursym == SYM_NONE) {
cursym = SYM_ENDLOOP;
} else {
nextsym = SYM_ENDLOOP;
}
loop = 0;
break;
// Ignore other characters
default:
break;
}
}
}
}
if (cursym == SYM_ENDLOOP) {
if (!phi) {
cerr<<"Error: Extra ']'\n";
abort();
}
// Write loop test
{
//br label %main.%d
builder->CreateBr(testbb);
//main.%d:
//%head.%d = phi i8 *[%head.%d, %main.%d], [%head.%d, %main.%d]
//Finish phi made at beginning of loop
phi->addIncoming(curhead, builder->GetInsertBlock());
Value *head_0 = phi;
//%tape.%d = load i8 *%head.%d
LoadInst *tape_0 = new LoadInst(head_0, tapereg, testbb);
//%test.%d = icmp eq i8 %tape.%d, 0
ICmpInst *test_0 = new ICmpInst(ICmpInst::ICMP_EQ, tape_0,
ConstantInt::get(APInt(8, 0)), testreg,
testbb);
//br i1 %test.%d, label %main.%d, label %main.%d
BasicBlock *bb_0 = new BasicBlock(label, brainf_func);
new BranchInst(bb_0, oldbb, test_0, testbb);
//main.%d:
builder->SetInsertPoint(bb_0);
//%head.%d = phi i8 *[%head.%d, %main.%d]
PHINode *phi_1 = builder->
CreatePHI(PointerType::get(IntegerType::Int8Ty), headreg);
phi_1->reserveOperandSpace(1);
phi_1->addIncoming(head_0, testbb);
curhead = phi_1;
}
return;
}
//End of the program, so go to return block
builder->CreateBr(endbb);
if (phi) {
cerr<<"Error: Missing ']'\n";
abort();
}
}

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//===-- BrainF.h - BrainF compiler class ----------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Sterling Stein and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===--------------------------------------------------------------------===//
//
// This class stores the data for the BrainF compiler so it doesn't have
// to pass all of it around. The main method is parse.
//
//===--------------------------------------------------------------------===//
#ifndef BRAINF_H
#define BRAINF_H
#include "llvm/Module.h"
#include "llvm/Support/LLVMBuilder.h"
using namespace llvm;
/// This class provides a parser for the BrainF language.
/// The class itself is made to store values during
/// parsing so they don't have to be passed around
/// as much.
class BrainF {
public:
/// Options for how BrainF should compile
enum CompileFlags {
flag_off = 0,
flag_arraybounds = 1
};
/// This is the main method. It parses BrainF from in1
/// and returns the module with a function
/// void brainf()
/// containing the resulting code.
/// On error, it calls abort.
/// The caller must delete the returned module.
Module *parse(std::istream *in1, int mem, CompileFlags cf);
protected:
/// The different symbols in the BrainF language
enum Symbol {
SYM_NONE,
SYM_READ,
SYM_WRITE,
SYM_MOVE,
SYM_CHANGE,
SYM_LOOP,
SYM_ENDLOOP,
SYM_EOF
};
/// Names of the different parts of the language.
/// Tape is used for reading and writing the tape.
/// headreg is used for the position of the head.
/// label is used for the labels for the BasicBlocks.
/// testreg is used for testing the loop exit condition.
static const char *tapereg;
static const char *headreg;
static const char *label;
static const char *testreg;
/// Put the brainf function preamble and other fixed pieces of code
void header();
/// The main loop for parsing. It calls itself recursively
/// to handle the depth of nesting of "[]".
void readloop(PHINode *phi, BasicBlock *oldbb, BasicBlock *testbb);
/// Constants during parsing
int memtotal;
CompileFlags comflag;
std::istream *in;
Module *module;
Function *brainf_func;
Function *getchar_func;
Function *putchar_func;
Value *ptr_arr;
Value *ptr_arrmax;
BasicBlock *endbb;
BasicBlock *aberrorbb;
/// Variables
LLVMBuilder *builder;
Value *curhead;
};
#endif

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//===-- BrainFDriver.cpp - BrainF compiler driver -----------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Sterling Stein and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===--------------------------------------------------------------------===//
//
// This program converts the BrainF language into LLVM assembly,
// which it can then run using the JIT or output as BitCode.
//
// This implementation has a tape of 65536 bytes,
// with the head starting in the middle.
// Range checking is off by default, so be careful.
// It can be enabled with -abc.
//
// Use:
// ./BrainF -jit prog.bf #Run program now
// ./BrainF -jit -abc prog.bf #Run program now safely
// ./BrainF prog.bf #Write as BitCode
//
// lli prog.bf.bc #Run generated BitCode
// llvm-ld -native -o=prog prog.bf.bc #Compile BitCode into native executable
//
//===--------------------------------------------------------------------===//
#include "BrainF.h"
#include "llvm/Constants.h"
#include "llvm/ModuleProvider.h"
#include "llvm/Analysis/Verifier.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/ExecutionEngine/GenericValue.h"
#include "llvm/ExecutionEngine/JIT.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ManagedStatic.h"
#include <fstream>
#include <iostream>
using namespace llvm;
//Command line options
static cl::opt<std::string>
InputFilename(cl::Positional, cl::desc("<input brainf>"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
static cl::opt<bool>
ArrayBoundsChecking("abc", cl::desc("Enable array bounds checking"));
static cl::opt<bool>
JIT("jit", cl::desc("Run program Just-In-Time"));
//Add main function so can be fully compiled
void addMainFunction(Module *mod) {
//define i32 @main(i32 %argc, i8 **%argv)
Function *main_func = cast<Function>(mod->
getOrInsertFunction("main", IntegerType::Int32Ty, IntegerType::Int32Ty,
PointerType::get(PointerType::get(
IntegerType::Int8Ty)), NULL));
{
Function::arg_iterator args = main_func->arg_begin();
Value *arg_0 = args++;
arg_0->setName("argc");
Value *arg_1 = args++;
arg_1->setName("argv");
}
//main.0:
BasicBlock *bb = new BasicBlock("main.0", main_func);
//call void @brainf()
{
CallInst *brainf_call = new CallInst(mod->getFunction("brainf"),
"", bb);
brainf_call->setTailCall(false);
}
//ret i32 0
new ReturnInst(ConstantInt::get(APInt(32, 0)), bb);
}
int main(int argc, char **argv) {
cl::ParseCommandLineOptions(argc, argv, " BrainF compiler\n");
if (InputFilename == "") {
cerr<<"Error: You must specify the filename of the program to "
"be compiled. Use --help to see the options.\n";
abort();
}
//Get the output stream
std::ostream *out = &std::cout;
if (!JIT) {
if (OutputFilename == "") {
std::string base = InputFilename;
if (InputFilename == "-") {base = "a";}
//Use default filename
const char *suffix = ".bc";
OutputFilename = base+suffix;
}
if (OutputFilename != "-") {
out = new std::
ofstream(OutputFilename.c_str(),
std::ios::out | std::ios::trunc | std::ios::binary);
}
}
//Get the input stream
std::istream *in = &std::cin;
if (InputFilename != "-") {
in = new std::ifstream(InputFilename.c_str());
}
//Gather the compile flags
BrainF::CompileFlags cf = BrainF::flag_off;
if (ArrayBoundsChecking) {
cf = BrainF::CompileFlags(cf | BrainF::flag_arraybounds);
}
//Read the BrainF program
BrainF bf;
Module *mod = bf.parse(in, 65536, cf); //64 KiB
if (in != &std::cin) {delete in;}
addMainFunction(mod);
//Verify generated code
if (verifyModule(*mod)) {
cerr<<"Error: module failed verification. This shouldn't happen.\n";
abort();
}
//Write it out
if (JIT) {
cout<<"------- Running JIT -------\n";
ExistingModuleProvider *mp = new ExistingModuleProvider(mod);
ExecutionEngine *ee = ExecutionEngine::create(mp, false);
std::vector<GenericValue> args;
Function *brainf_func = mod->getFunction("brainf");
GenericValue gv = ee->runFunction(brainf_func, args);
} else {
WriteBitcodeToFile(mod, *out);
}
//Clean up
if (out != &std::cout) {delete out;}
delete mod;
llvm_shutdown();
return 0;
}

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##===- examples/BrainF/Makefile ----------------------------*- Makefile -*-===##
#
# The LLVM Compiler Infrastructure
#
# This file was developed by Sterling Stein and is distributed under
# the University of Illinois Open Source License. See LICENSE.TXT for details.
#
##===----------------------------------------------------------------------===##
LEVEL = ../..
TOOLNAME = BrainF
EXAMPLE_TOOL = 1
LINK_COMPONENTS := jit bitwriter native interpreter
include $(LEVEL)/Makefile.common

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@ -10,7 +10,7 @@ LEVEL=..
include $(LEVEL)/Makefile.config
PARALLEL_DIRS:= Fibonacci HowToUseJIT ModuleMaker
PARALLEL_DIRS:= BrainF Fibonacci HowToUseJIT ModuleMaker
ifeq ($(HAVE_PTHREAD),1)
PARALLEL_DIRS += ParallelJIT