1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-25 12:12:47 +01:00
llvm-mirror/lib/VMCore/Verifier.cpp
2002-04-07 22:33:13 +00:00

212 lines
8.2 KiB
C++

//===-- Verifier.cpp - Implement the Module Verifier -------------*- C++ -*-==//
//
// This file defines the function verifier interface, that can be used for some
// sanity checking of input to the system.
//
// Note that this does not provide full 'java style' security and verifications,
// instead it just tries to ensure that code is well formed.
//
// . There are no duplicated names in a symbol table... ie there !exist a val
// with the same name as something in the symbol table, but with a different
// address as what is in the symbol table...
// . Both of a binary operator's parameters are the same type
// . Verify that arithmetic and other things are only performed on first class
// types. No adding structures or arrays.
// . All of the constants in a switch statement are of the correct type
// . The code is in valid SSA form
// . It should be illegal to put a label into any other type (like a structure)
// or to return one. [except constant arrays!]
// . Right now 'add bool 0, 0' is valid. This isn't particularly good.
// * Only phi nodes can be self referential: 'add int %0, %0 ; <int>:0' is bad
// * PHI nodes must have an entry for each predecessor, with no extras.
// * All basic blocks should only end with terminator insts, not contain them
// * The entry node to a function must not have predecessors
// * All Instructions must be embeded into a basic block
// . Verify that none of the Value getType()'s are null.
// . Function's cannot take a void typed parameter
// . Verify that a function's argument list agrees with it's declared type.
// . Verify that arrays and structures have fixed elements: No unsized arrays.
// * It is illegal to specify a name for a void value.
// * It is illegal to have a internal function that is just a declaration
// . All other things that are tested by asserts spread about the code...
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/Verifier.h"
#include "llvm/Pass.h"
#include "llvm/Function.h"
#include "llvm/Module.h"
#include "llvm/BasicBlock.h"
#include "llvm/Type.h"
#include "llvm/iPHINode.h"
#include "llvm/SymbolTable.h"
#include "llvm/Support/CFG.h"
#include "Support/STLExtras.h"
#include <algorithm>
#if 0
#define t(x) (1 << (unsigned)Type::x)
#define SignedIntegralTypes (t(SByteTyID) | t(ShortTyID) | \
t(IntTyID) | t(LongTyID))
static long UnsignedIntegralTypes = t(UByteTyID) | t(UShortTyID) |
t(UIntTyID) | t(ULongTyID);
static const long FloatingPointTypes = t(FloatTyID) | t(DoubleTyID);
static const long IntegralTypes = SignedIntegralTypes | UnsignedIntegralTypes;
static long ValidTypes[Type::FirstDerivedTyID] = {
[(unsigned)Instruction::UnaryOps::Not] t(BoolTyID),
//[Instruction::UnaryOps::Add] = IntegralTypes,
// [Instruction::Sub] = IntegralTypes,
};
#undef t
#endif
// CheckFailed - A check failed, so print out the condition and the message that
// failed. This provides a nice place to put a breakpoint if you want to see
// why something is not correct.
//
static inline void CheckFailed(const char *Cond, const std::string &Message,
const Value *V1 = 0, const Value *V2 = 0) {
std::cerr << Message << "\n";
if (V1) { V1->dump(); std::cerr << "\n"; }
if (V2) { V2->dump(); std::cerr << "\n"; }
}
// Assert - We know that cond should be true, if not print an error message.
#define Assert(C, M) \
do { if (!(C)) { CheckFailed(#C, M); Broken = true; } } while (0)
#define Assert1(C, M, V1) \
do { if (!(C)) { CheckFailed(#C, M, V1); Broken = true; } } while (0)
#define Assert2(C, M, V1, V2) \
do { if (!(C)) { CheckFailed(#C, M, V1, V2); Broken = true; } } while (0)
// verifyInstruction - Verify that a non-terminator instruction is well formed.
//
static bool verifyInstruction(const Instruction *I) {
bool Broken = false;
assert(I->getParent() && "Instruction not embedded in basic block!");
Assert1(!isa<TerminatorInst>(I),
"Terminator instruction found embedded in basic block!\n", I);
// Check that all uses of the instruction, if they are instructions
// themselves, actually have parent basic blocks.
//
for (User::use_const_iterator UI = I->use_begin(), UE = I->use_end();
UI != UE; ++UI) {
if (Instruction *Used = dyn_cast<Instruction>(*UI))
Assert2(Used->getParent() != 0, "Instruction referencing instruction not"
" embeded in a basic block!", I, Used);
}
// Check that PHI nodes look ok
if (const PHINode *PN = dyn_cast<PHINode>(I)) {
std::vector<const BasicBlock*> Preds(pred_begin(I->getParent()),
pred_end(I->getParent()));
// Loop over all of the incoming values, make sure that there are
// predecessors for each one...
//
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
const BasicBlock *BB = PN->getIncomingBlock(i);
std::vector<const BasicBlock*>::iterator PI =
find(Preds.begin(), Preds.end(), BB);
Assert2(PI != Preds.end(), "PHI node has entry for basic block that"
" is not a predecessor!", PN, BB);
if (PI != Preds.end()) Preds.erase(PI);
}
// There should be no entries left in the predecessor list...
for (std::vector<const BasicBlock*>::iterator I = Preds.begin(),
E = Preds.end(); I != E; ++I)
Assert2(0, "PHI node does not have entry for a predecessor basic block!",
PN, *I);
} else {
// Check that non-phi nodes are not self referential...
for (Value::use_const_iterator UI = I->use_begin(), UE = I->use_end();
UI != UE; ++UI)
Assert1(*UI != (const User*)I,
"Only PHI nodes may reference their own value!", I);
}
return Broken;
}
// verifyBasicBlock - Verify that a basic block is well formed...
//
static bool verifyBasicBlock(const BasicBlock *BB) {
bool Broken = false;
Assert1(BB->getTerminator(), "Basic Block does not have terminator!\n", BB);
// Verify all instructions, except the terminator...
Broken |= reduce_apply_bool(BB->begin(), BB->end()-1, verifyInstruction);
return Broken;
}
// verifySymbolTable - Verify that a method or module symbol table is ok
//
static bool verifySymbolTable(const SymbolTable *ST) {
if (ST == 0) return false;
bool Broken = false;
// Loop over all of the types in the symbol table...
for (SymbolTable::const_iterator TI = ST->begin(), TE = ST->end();
TI != TE; ++TI)
for (SymbolTable::type_const_iterator I = TI->second.begin(),
E = TI->second.end(); I != E; ++I) {
Value *V = I->second;
// Check that there are no void typed values in the symbol table. Values
// with a void type cannot be put into symbol tables because they cannot
// have names!
Assert1(V->getType() != Type::VoidTy,
"Values with void type are not allowed to have names!\n", V);
}
return Broken;
}
// verifyMethod - Verify that a method is ok. Return true if not so that
// verifyModule and direct clients of the verifyMethod function are correctly
// informed.
//
bool verifyMethod(const Function *F) {
if (F->isExternal()) return false; // Can happen if called by verifyModule
bool Broken = verifySymbolTable(F->getSymbolTable());
Assert1(!F->isExternal() || F->hasExternalLinkage(),
"Function cannot be an 'internal' 'declare'ation!", F);
const BasicBlock *Entry = F->getEntryNode();
Assert1(pred_begin(Entry) == pred_end(Entry),
"Entry block to method must not have predecessors!", Entry);
Broken |= reduce_apply_bool(F->begin(), F->end(), verifyBasicBlock);
return Broken;
}
namespace { // Anonymous namespace for class
struct VerifierPass : public MethodPass {
bool doInitialization(Module *M) {
verifySymbolTable(M->getSymbolTable());
return false;
}
bool runOnMethod(Method *M) { verifyMethod(M); return false; }
};
}
Pass *createVerifierPass() {
return new VerifierPass();
}
// verifyModule - Check a module for errors, printing messages on stderr.
// Return true if the module is corrupt.
//
bool verifyModule(const Module *M) {
return verifySymbolTable(M->getSymbolTable()) |
reduce_apply_bool(M->begin(), M->end(), verifyMethod);
}