2008-11-02 13:52:50 +08:00
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|
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//===- MergeFunctions.cpp - Merge identical functions ---------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This pass looks for equivalent functions that are mergable and folds them.
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//
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// A hash is computed from the function, based on its type and number of
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// basic blocks.
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//
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// Once all hashes are computed, we perform an expensive equality comparison
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// on each function pair. This takes n^2/2 comparisons per bucket, so it's
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// important that the hash function be high quality. The equality comparison
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// iterates through each instruction in each basic block.
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//
|
2010-05-13 13:48:45 +08:00
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// When a match is found the functions are folded. If both functions are
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// overridable, we move the functionality into a new internal function and
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// leave two overridable thunks to it.
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2008-11-02 13:52:50 +08:00
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//
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//===----------------------------------------------------------------------===//
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//
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// Future work:
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//
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// * virtual functions.
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//
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// Many functions have their address taken by the virtual function table for
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// the object they belong to. However, as long as it's only used for a lookup
|
2010-08-08 13:04:23 +08:00
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// and call, this is irrelevant, and we'd like to fold such functions.
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2008-11-02 13:52:50 +08:00
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//
|
2010-08-02 13:23:03 +08:00
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// * switch from n^2 pair-wise comparisons to an n-way comparison for each
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// bucket.
|
2010-05-13 13:48:45 +08:00
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//
|
2010-08-08 13:04:23 +08:00
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// * be smarter about bitcasts.
|
2010-05-13 13:48:45 +08:00
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//
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// In order to fold functions, we will sometimes add either bitcast instructions
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// or bitcast constant expressions. Unfortunately, this can confound further
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// analysis since the two functions differ where one has a bitcast and the
|
2010-08-08 13:04:23 +08:00
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// other doesn't. We should learn to look through bitcasts.
|
2010-05-13 13:48:45 +08:00
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//
|
2008-11-02 13:52:50 +08:00
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//===----------------------------------------------------------------------===//
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#include "llvm/Transforms/IPO.h"
|
2012-12-04 00:50:05 +08:00
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#include "llvm/ADT/DenseSet.h"
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#include "llvm/ADT/FoldingSet.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/SmallSet.h"
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#include "llvm/ADT/Statistic.h"
|
2014-03-04 19:01:28 +08:00
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|
|
#include "llvm/IR/CallSite.h"
|
2013-01-02 19:36:10 +08:00
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|
#include "llvm/IR/Constants.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/IRBuilder.h"
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#include "llvm/IR/InlineAsm.h"
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#include "llvm/IR/Instructions.h"
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#include "llvm/IR/LLVMContext.h"
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#include "llvm/IR/Module.h"
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|
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#include "llvm/IR/Operator.h"
|
2014-03-04 19:17:44 +08:00
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|
|
#include "llvm/IR/ValueHandle.h"
|
2008-11-02 13:52:50 +08:00
|
|
|
#include "llvm/Pass.h"
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|
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#include "llvm/Support/Debug.h"
|
2009-07-12 04:10:48 +08:00
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|
#include "llvm/Support/ErrorHandling.h"
|
2009-07-25 08:23:56 +08:00
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|
|
#include "llvm/Support/raw_ostream.h"
|
2010-08-31 16:29:37 +08:00
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|
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#include <vector>
|
2008-11-02 13:52:50 +08:00
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|
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using namespace llvm;
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|
|
2014-04-22 10:55:47 +08:00
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|
|
#define DEBUG_TYPE "mergefunc"
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|
|
2008-11-02 13:52:50 +08:00
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|
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STATISTIC(NumFunctionsMerged, "Number of functions merged");
|
2010-09-07 09:42:10 +08:00
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STATISTIC(NumThunksWritten, "Number of thunks generated");
|
2011-01-25 16:56:50 +08:00
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|
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STATISTIC(NumAliasesWritten, "Number of aliases generated");
|
2010-09-07 09:42:10 +08:00
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|
|
STATISTIC(NumDoubleWeak, "Number of new functions created");
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2013-04-20 07:06:44 +08:00
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|
|
/// Returns the type id for a type to be hashed. We turn pointer types into
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|
|
/// integers here because the actual compare logic below considers pointers and
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|
|
/// integers of the same size as equal.
|
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|
|
static Type::TypeID getTypeIDForHash(Type *Ty) {
|
|
|
|
if (Ty->isPointerTy())
|
|
|
|
return Type::IntegerTyID;
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|
|
|
return Ty->getTypeID();
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|
|
|
}
|
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|
2011-01-28 16:43:14 +08:00
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|
|
/// Creates a hash-code for the function which is the same for any two
|
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|
|
/// functions that will compare equal, without looking at the instructions
|
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|
|
/// inside the function.
|
|
|
|
static unsigned profileFunction(const Function *F) {
|
2011-07-18 12:54:35 +08:00
|
|
|
FunctionType *FTy = F->getFunctionType();
|
2010-09-05 16:22:49 +08:00
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|
|
FoldingSetNodeID ID;
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|
|
ID.AddInteger(F->size());
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|
|
ID.AddInteger(F->getCallingConv());
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|
|
ID.AddBoolean(F->hasGC());
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|
|
ID.AddBoolean(FTy->isVarArg());
|
2013-04-20 07:06:44 +08:00
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|
|
ID.AddInteger(getTypeIDForHash(FTy->getReturnType()));
|
2010-09-05 16:22:49 +08:00
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|
|
for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
|
2013-04-20 07:06:44 +08:00
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|
|
ID.AddInteger(getTypeIDForHash(FTy->getParamType(i)));
|
2010-09-05 16:22:49 +08:00
|
|
|
return ID.ComputeHash();
|
2008-11-02 13:52:50 +08:00
|
|
|
}
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|
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|
|
2010-09-07 09:42:10 +08:00
|
|
|
namespace {
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|
|
|
2011-01-28 16:19:00 +08:00
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|
|
/// ComparableFunction - A struct that pairs together functions with a
|
2012-10-09 00:38:25 +08:00
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|
|
/// DataLayout so that we can keep them together as elements in the DenseSet.
|
2010-09-05 16:22:49 +08:00
|
|
|
class ComparableFunction {
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|
public:
|
2010-09-05 17:00:32 +08:00
|
|
|
static const ComparableFunction EmptyKey;
|
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|
|
static const ComparableFunction TombstoneKey;
|
2012-10-09 00:38:25 +08:00
|
|
|
static DataLayout * const LookupOnly;
|
2010-09-05 17:00:32 +08:00
|
|
|
|
2014-02-25 07:12:18 +08:00
|
|
|
ComparableFunction(Function *Func, const DataLayout *DL)
|
2014-02-21 08:06:31 +08:00
|
|
|
: Func(Func), Hash(profileFunction(Func)), DL(DL) {}
|
2010-09-05 16:22:49 +08:00
|
|
|
|
2010-09-05 17:00:32 +08:00
|
|
|
Function *getFunc() const { return Func; }
|
|
|
|
unsigned getHash() const { return Hash; }
|
2014-02-25 07:12:18 +08:00
|
|
|
const DataLayout *getDataLayout() const { return DL; }
|
2010-09-05 16:22:49 +08:00
|
|
|
|
2010-09-05 17:00:32 +08:00
|
|
|
// Drops AssertingVH reference to the function. Outside of debug mode, this
|
|
|
|
// does nothing.
|
|
|
|
void release() {
|
|
|
|
assert(Func &&
|
|
|
|
"Attempted to release function twice, or release empty/tombstone!");
|
2014-04-25 13:29:35 +08:00
|
|
|
Func = nullptr;
|
2010-09-05 16:22:49 +08:00
|
|
|
}
|
2010-09-05 17:00:32 +08:00
|
|
|
|
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|
|
private:
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|
|
|
explicit ComparableFunction(unsigned Hash)
|
2014-04-25 13:29:35 +08:00
|
|
|
: Func(nullptr), Hash(Hash), DL(nullptr) {}
|
2010-09-05 17:00:32 +08:00
|
|
|
|
|
|
|
AssertingVH<Function> Func;
|
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|
|
unsigned Hash;
|
2014-02-25 07:12:18 +08:00
|
|
|
const DataLayout *DL;
|
2010-09-05 16:22:49 +08:00
|
|
|
};
|
|
|
|
|
2010-09-05 17:00:32 +08:00
|
|
|
const ComparableFunction ComparableFunction::EmptyKey = ComparableFunction(0);
|
|
|
|
const ComparableFunction ComparableFunction::TombstoneKey =
|
|
|
|
ComparableFunction(1);
|
2012-10-09 00:38:25 +08:00
|
|
|
DataLayout *const ComparableFunction::LookupOnly = (DataLayout*)(-1);
|
2010-09-05 17:00:32 +08:00
|
|
|
|
2010-09-07 09:42:10 +08:00
|
|
|
}
|
2010-09-05 17:00:32 +08:00
|
|
|
|
|
|
|
namespace llvm {
|
|
|
|
template <>
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|
|
struct DenseMapInfo<ComparableFunction> {
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|
|
static ComparableFunction getEmptyKey() {
|
|
|
|
return ComparableFunction::EmptyKey;
|
|
|
|
}
|
|
|
|
static ComparableFunction getTombstoneKey() {
|
|
|
|
return ComparableFunction::TombstoneKey;
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|
|
|
}
|
|
|
|
static unsigned getHashValue(const ComparableFunction &CF) {
|
|
|
|
return CF.getHash();
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|
|
|
}
|
|
|
|
static bool isEqual(const ComparableFunction &LHS,
|
|
|
|
const ComparableFunction &RHS);
|
|
|
|
};
|
|
|
|
}
|
|
|
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|
|
|
namespace {
|
|
|
|
|
2010-08-08 13:04:23 +08:00
|
|
|
/// FunctionComparator - Compares two functions to determine whether or not
|
2012-10-09 00:38:25 +08:00
|
|
|
/// they will generate machine code with the same behaviour. DataLayout is
|
2010-08-08 13:04:23 +08:00
|
|
|
/// used if available. The comparator always fails conservatively (erring on the
|
|
|
|
/// side of claiming that two functions are different).
|
2010-08-02 13:23:03 +08:00
|
|
|
class FunctionComparator {
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|
|
public:
|
2014-02-21 08:06:31 +08:00
|
|
|
FunctionComparator(const DataLayout *DL, const Function *F1,
|
2010-08-31 13:53:05 +08:00
|
|
|
const Function *F2)
|
2014-02-21 08:06:31 +08:00
|
|
|
: F1(F1), F2(F2), DL(DL) {}
|
2010-08-02 13:23:03 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Test whether the two functions have equivalent behaviour.
|
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|
|
bool compare();
|
2010-08-02 13:23:03 +08:00
|
|
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|
private:
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Test whether two basic blocks have equivalent behaviour.
|
|
|
|
bool compare(const BasicBlock *BB1, const BasicBlock *BB2);
|
2010-08-02 13:23:03 +08:00
|
|
|
|
2014-05-07 17:05:10 +08:00
|
|
|
/// Constants comparison.
|
|
|
|
/// Its analog to lexicographical comparison between hypothetical numbers
|
|
|
|
/// of next format:
|
|
|
|
/// <bitcastability-trait><raw-bit-contents>
|
|
|
|
///
|
|
|
|
/// 1. Bitcastability.
|
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|
|
/// Check whether L's type could be losslessly bitcasted to R's type.
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|
|
/// On this stage method, in case when lossless bitcast is not possible
|
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|
|
/// method returns -1 or 1, thus also defining which type is greater in
|
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|
|
/// context of bitcastability.
|
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|
|
/// Stage 0: If types are equal in terms of cmpTypes, then we can go straight
|
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|
|
/// to the contents comparison.
|
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|
|
/// If types differ, remember types comparison result and check
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|
|
/// whether we still can bitcast types.
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|
|
/// Stage 1: Types that satisfies isFirstClassType conditions are always
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|
|
/// greater then others.
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|
|
/// Stage 2: Vector is greater then non-vector.
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|
|
/// If both types are vectors, then vector with greater bitwidth is
|
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|
|
/// greater.
|
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|
|
/// If both types are vectors with the same bitwidth, then types
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|
|
/// are bitcastable, and we can skip other stages, and go to contents
|
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|
|
/// comparison.
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|
|
/// Stage 3: Pointer types are greater than non-pointers. If both types are
|
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|
|
/// pointers of the same address space - go to contents comparison.
|
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|
|
/// Different address spaces: pointer with greater address space is
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|
|
/// greater.
|
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|
|
/// Stage 4: Types are neither vectors, nor pointers. And they differ.
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|
/// We don't know how to bitcast them. So, we better don't do it,
|
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|
/// and return types comparison result (so it determines the
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|
|
/// relationship among constants we don't know how to bitcast).
|
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|
///
|
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|
|
/// Just for clearance, let's see how the set of constants could look
|
|
|
|
/// on single dimension axis:
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|
///
|
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|
|
/// [NFCT], [FCT, "others"], [FCT, pointers], [FCT, vectors]
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|
|
/// Where: NFCT - Not a FirstClassType
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|
|
/// FCT - FirstClassTyp:
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|
///
|
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|
|
/// 2. Compare raw contents.
|
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|
|
/// It ignores types on this stage and only compares bits from L and R.
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|
|
/// Returns 0, if L and R has equivalent contents.
|
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|
|
/// -1 or 1 if values are different.
|
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|
|
/// Pretty trivial:
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|
|
/// 2.1. If contents are numbers, compare numbers.
|
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|
|
/// Ints with greater bitwidth are greater. Ints with same bitwidths
|
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|
|
/// compared by their contents.
|
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|
|
/// 2.2. "And so on". Just to avoid discrepancies with comments
|
|
|
|
/// perhaps it would be better to read the implementation itself.
|
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|
|
/// 3. And again about overall picture. Let's look back at how the ordered set
|
|
|
|
/// of constants will look like:
|
|
|
|
/// [NFCT], [FCT, "others"], [FCT, pointers], [FCT, vectors]
|
|
|
|
///
|
|
|
|
/// Now look, what could be inside [FCT, "others"], for example:
|
|
|
|
/// [FCT, "others"] =
|
|
|
|
/// [
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|
|
|
/// [double 0.1], [double 1.23],
|
|
|
|
/// [i32 1], [i32 2],
|
|
|
|
/// { double 1.0 }, ; StructTyID, NumElements = 1
|
|
|
|
/// { i32 1 }, ; StructTyID, NumElements = 1
|
|
|
|
/// { double 1, i32 1 }, ; StructTyID, NumElements = 2
|
|
|
|
/// { i32 1, double 1 } ; StructTyID, NumElements = 2
|
|
|
|
/// ]
|
|
|
|
///
|
|
|
|
/// Let's explain the order. Float numbers will be less than integers, just
|
|
|
|
/// because of cmpType terms: FloatTyID < IntegerTyID.
|
|
|
|
/// Floats (with same fltSemantics) are sorted according to their value.
|
|
|
|
/// Then you can see integers, and they are, like a floats,
|
|
|
|
/// could be easy sorted among each others.
|
|
|
|
/// The structures. Structures are grouped at the tail, again because of their
|
|
|
|
/// TypeID: StructTyID > IntegerTyID > FloatTyID.
|
|
|
|
/// Structures with greater number of elements are greater. Structures with
|
|
|
|
/// greater elements going first are greater.
|
|
|
|
/// The same logic with vectors, arrays and other possible complex types.
|
|
|
|
///
|
|
|
|
/// Bitcastable constants.
|
|
|
|
/// Let's assume, that some constant, belongs to some group of
|
|
|
|
/// "so-called-equal" values with different types, and at the same time
|
|
|
|
/// belongs to another group of constants with equal types
|
|
|
|
/// and "really" equal values.
|
|
|
|
///
|
|
|
|
/// Now, prove that this is impossible:
|
|
|
|
///
|
|
|
|
/// If constant A with type TyA is bitcastable to B with type TyB, then:
|
|
|
|
/// 1. All constants with equal types to TyA, are bitcastable to B. Since
|
|
|
|
/// those should be vectors (if TyA is vector), pointers
|
|
|
|
/// (if TyA is pointer), or else (if TyA equal to TyB), those types should
|
|
|
|
/// be equal to TyB.
|
|
|
|
/// 2. All constants with non-equal, but bitcastable types to TyA, are
|
|
|
|
/// bitcastable to B.
|
|
|
|
/// Once again, just because we allow it to vectors and pointers only.
|
|
|
|
/// This statement could be expanded as below:
|
|
|
|
/// 2.1. All vectors with equal bitwidth to vector A, has equal bitwidth to
|
|
|
|
/// vector B, and thus bitcastable to B as well.
|
|
|
|
/// 2.2. All pointers of the same address space, no matter what they point to,
|
|
|
|
/// bitcastable. So if C is pointer, it could be bitcasted to A and to B.
|
|
|
|
/// So any constant equal or bitcastable to A is equal or bitcastable to B.
|
|
|
|
/// QED.
|
|
|
|
///
|
|
|
|
/// In another words, for pointers and vectors, we ignore top-level type and
|
|
|
|
/// look at their particular properties (bit-width for vectors, and
|
|
|
|
/// address space for pointers).
|
|
|
|
/// If these properties are equal - compare their contents.
|
|
|
|
int cmpConstants(const Constant *L, const Constant *R);
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Assign or look up previously assigned numbers for the two values, and
|
|
|
|
/// return whether the numbers are equal. Numbers are assigned in the order
|
|
|
|
/// visited.
|
2014-05-07 19:11:39 +08:00
|
|
|
/// Comparison order:
|
|
|
|
/// Stage 0: Value that is function itself is always greater then others.
|
|
|
|
/// If left and right values are references to their functions, then
|
|
|
|
/// they are equal.
|
|
|
|
/// Stage 1: Constants are greater than non-constants.
|
|
|
|
/// If both left and right are constants, then the result of
|
|
|
|
/// cmpConstants is used as cmpValues result.
|
|
|
|
/// Stage 2: InlineAsm instances are greater than others. If both left and
|
|
|
|
/// right are InlineAsm instances, InlineAsm* pointers casted to
|
|
|
|
/// integers and compared as numbers.
|
|
|
|
/// Stage 3: For all other cases we compare order we meet these values in
|
|
|
|
/// their functions. If right value was met first during scanning,
|
|
|
|
/// then left value is greater.
|
|
|
|
/// In another words, we compare serial numbers, for more details
|
|
|
|
/// see comments for sn_mapL and sn_mapR.
|
|
|
|
int cmpValues(const Value *L, const Value *R);
|
|
|
|
|
|
|
|
bool enumerate(const Value *V1, const Value *V2) {
|
|
|
|
return cmpValues(V1, V2) == 0;
|
|
|
|
}
|
2010-08-02 13:23:03 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Compare two Instructions for equivalence, similar to
|
|
|
|
/// Instruction::isSameOperationAs but with modifications to the type
|
2010-08-08 13:04:23 +08:00
|
|
|
/// comparison.
|
2014-05-16 19:02:22 +08:00
|
|
|
/// Stages are listed in "most significant stage first" order:
|
|
|
|
/// On each stage below, we do comparison between some left and right
|
|
|
|
/// operation parts. If parts are non-equal, we assign parts comparison
|
|
|
|
/// result to the operation comparison result and exit from method.
|
|
|
|
/// Otherwise we proceed to the next stage.
|
|
|
|
/// Stages:
|
|
|
|
/// 1. Operations opcodes. Compared as numbers.
|
|
|
|
/// 2. Number of operands.
|
|
|
|
/// 3. Operation types. Compared with cmpType method.
|
|
|
|
/// 4. Compare operation subclass optional data as stream of bytes:
|
|
|
|
/// just convert it to integers and call cmpNumbers.
|
|
|
|
/// 5. Compare in operation operand types with cmpType in
|
|
|
|
/// most significant operand first order.
|
|
|
|
/// 6. Last stage. Check operations for some specific attributes.
|
|
|
|
/// For example, for Load it would be:
|
|
|
|
/// 6.1.Load: volatile (as boolean flag)
|
|
|
|
/// 6.2.Load: alignment (as integer numbers)
|
|
|
|
/// 6.3.Load: synch-scope (as integer numbers)
|
|
|
|
/// On this stage its better to see the code, since its not more than 10-15
|
|
|
|
/// strings for particular instruction, and could change sometimes.
|
|
|
|
int cmpOperation(const Instruction *L, const Instruction *R) const;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
bool isEquivalentOperation(const Instruction *I1,
|
2014-05-16 19:02:22 +08:00
|
|
|
const Instruction *I2) const {
|
|
|
|
return cmpOperation(I1, I2) == 0;
|
|
|
|
}
|
2010-08-02 13:23:03 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Compare two GEPs for equivalent pointer arithmetic.
|
2014-05-16 19:55:02 +08:00
|
|
|
/// Parts to be compared for each comparison stage,
|
|
|
|
/// most significant stage first:
|
|
|
|
/// 1. Address space. As numbers.
|
|
|
|
/// 2. Constant offset, (if "DataLayout *DL" field is not NULL,
|
|
|
|
/// using GEPOperator::accumulateConstantOffset method).
|
|
|
|
/// 3. Pointer operand type (using cmpType method).
|
|
|
|
/// 4. Number of operands.
|
|
|
|
/// 5. Compare operands, using cmpValues method.
|
|
|
|
int cmpGEP(const GEPOperator *GEPL, const GEPOperator *GEPR);
|
|
|
|
int cmpGEP(const GetElementPtrInst *GEPL, const GetElementPtrInst *GEPR) {
|
|
|
|
return cmpGEP(cast<GEPOperator>(GEPL), cast<GEPOperator>(GEPR));
|
|
|
|
}
|
|
|
|
|
|
|
|
bool isEquivalentGEP(const GEPOperator *GEP1, const GEPOperator *GEP2) {
|
|
|
|
return cmpGEP(GEP1, GEP2) == 0;
|
|
|
|
}
|
2010-08-02 13:23:03 +08:00
|
|
|
bool isEquivalentGEP(const GetElementPtrInst *GEP1,
|
2010-08-08 13:04:23 +08:00
|
|
|
const GetElementPtrInst *GEP2) {
|
2010-08-02 13:23:03 +08:00
|
|
|
return isEquivalentGEP(cast<GEPOperator>(GEP1), cast<GEPOperator>(GEP2));
|
|
|
|
}
|
2009-06-12 16:04:51 +08:00
|
|
|
|
2014-03-13 19:54:50 +08:00
|
|
|
/// cmpType - compares two types,
|
|
|
|
/// defines total ordering among the types set.
|
|
|
|
///
|
|
|
|
/// Return values:
|
|
|
|
/// 0 if types are equal,
|
|
|
|
/// -1 if Left is less than Right,
|
|
|
|
/// +1 if Left is greater than Right.
|
|
|
|
///
|
|
|
|
/// Description:
|
|
|
|
/// Comparison is broken onto stages. Like in lexicographical comparison
|
|
|
|
/// stage coming first has higher priority.
|
|
|
|
/// On each explanation stage keep in mind total ordering properties.
|
|
|
|
///
|
2014-03-14 16:17:19 +08:00
|
|
|
/// 0. Before comparison we coerce pointer types of 0 address space to
|
|
|
|
/// integer.
|
2014-03-13 19:54:50 +08:00
|
|
|
/// We also don't bother with same type at left and right, so
|
|
|
|
/// just return 0 in this case.
|
|
|
|
///
|
|
|
|
/// 1. If types are of different kind (different type IDs).
|
|
|
|
/// Return result of type IDs comparison, treating them as numbers.
|
|
|
|
/// 2. If types are vectors or integers, compare Type* values as numbers.
|
|
|
|
/// 3. Types has same ID, so check whether they belongs to the next group:
|
|
|
|
/// * Void
|
|
|
|
/// * Float
|
|
|
|
/// * Double
|
|
|
|
/// * X86_FP80
|
|
|
|
/// * FP128
|
|
|
|
/// * PPC_FP128
|
|
|
|
/// * Label
|
|
|
|
/// * Metadata
|
|
|
|
/// If so - return 0, yes - we can treat these types as equal only because
|
|
|
|
/// their IDs are same.
|
|
|
|
/// 4. If Left and Right are pointers, return result of address space
|
|
|
|
/// comparison (numbers comparison). We can treat pointer types of same
|
|
|
|
/// address space as equal.
|
|
|
|
/// 5. If types are complex.
|
|
|
|
/// Then both Left and Right are to be expanded and their element types will
|
|
|
|
/// be checked with the same way. If we get Res != 0 on some stage, return it.
|
|
|
|
/// Otherwise return 0.
|
|
|
|
/// 6. For all other cases put llvm_unreachable.
|
|
|
|
int cmpType(Type *TyL, Type *TyR) const;
|
|
|
|
|
|
|
|
bool isEquivalentType(Type *Ty1, Type *Ty2) const {
|
|
|
|
return cmpType(Ty1, Ty2) == 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
int cmpNumbers(uint64_t L, uint64_t R) const;
|
2010-08-02 13:23:03 +08:00
|
|
|
|
2014-05-07 17:05:10 +08:00
|
|
|
int cmpAPInt(const APInt &L, const APInt &R) const;
|
|
|
|
int cmpAPFloat(const APFloat &L, const APFloat &R) const;
|
2014-05-16 16:55:34 +08:00
|
|
|
int cmpStrings(StringRef L, StringRef R) const;
|
|
|
|
int cmpAttrs(const AttributeSet L, const AttributeSet R) const;
|
2014-05-07 17:05:10 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
// The two functions undergoing comparison.
|
2010-08-31 13:53:05 +08:00
|
|
|
const Function *F1, *F2;
|
2010-08-02 13:23:03 +08:00
|
|
|
|
2014-02-21 08:06:31 +08:00
|
|
|
const DataLayout *DL;
|
2010-08-02 13:23:03 +08:00
|
|
|
|
2014-05-07 19:11:39 +08:00
|
|
|
/// Assign serial numbers to values from left function, and values from
|
|
|
|
/// right function.
|
|
|
|
/// Explanation:
|
|
|
|
/// Being comparing functions we need to compare values we meet at left and
|
|
|
|
/// right sides.
|
|
|
|
/// Its easy to sort things out for external values. It just should be
|
|
|
|
/// the same value at left and right.
|
|
|
|
/// But for local values (those were introduced inside function body)
|
|
|
|
/// we have to ensure they were introduced at exactly the same place,
|
|
|
|
/// and plays the same role.
|
|
|
|
/// Let's assign serial number to each value when we meet it first time.
|
|
|
|
/// Values that were met at same place will be with same serial numbers.
|
|
|
|
/// In this case it would be good to explain few points about values assigned
|
|
|
|
/// to BBs and other ways of implementation (see below).
|
|
|
|
///
|
|
|
|
/// 1. Safety of BB reordering.
|
|
|
|
/// It's safe to change the order of BasicBlocks in function.
|
|
|
|
/// Relationship with other functions and serial numbering will not be
|
|
|
|
/// changed in this case.
|
|
|
|
/// As follows from FunctionComparator::compare(), we do CFG walk: we start
|
|
|
|
/// from the entry, and then take each terminator. So it doesn't matter how in
|
|
|
|
/// fact BBs are ordered in function. And since cmpValues are called during
|
|
|
|
/// this walk, the numbering depends only on how BBs located inside the CFG.
|
|
|
|
/// So the answer is - yes. We will get the same numbering.
|
|
|
|
///
|
|
|
|
/// 2. Impossibility to use dominance properties of values.
|
|
|
|
/// If we compare two instruction operands: first is usage of local
|
|
|
|
/// variable AL from function FL, and second is usage of local variable AR
|
|
|
|
/// from FR, we could compare their origins and check whether they are
|
|
|
|
/// defined at the same place.
|
|
|
|
/// But, we are still not able to compare operands of PHI nodes, since those
|
|
|
|
/// could be operands from further BBs we didn't scan yet.
|
|
|
|
/// So it's impossible to use dominance properties in general.
|
|
|
|
DenseMap<const Value*, int> sn_mapL, sn_mapR;
|
2010-08-02 13:23:03 +08:00
|
|
|
};
|
2011-01-28 15:36:21 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
}
|
|
|
|
|
2014-03-13 19:54:50 +08:00
|
|
|
int FunctionComparator::cmpNumbers(uint64_t L, uint64_t R) const {
|
|
|
|
if (L < R) return -1;
|
|
|
|
if (L > R) return 1;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-05-07 17:05:10 +08:00
|
|
|
int FunctionComparator::cmpAPInt(const APInt &L, const APInt &R) const {
|
|
|
|
if (int Res = cmpNumbers(L.getBitWidth(), R.getBitWidth()))
|
|
|
|
return Res;
|
|
|
|
if (L.ugt(R)) return 1;
|
|
|
|
if (R.ugt(L)) return -1;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
int FunctionComparator::cmpAPFloat(const APFloat &L, const APFloat &R) const {
|
|
|
|
if (int Res = cmpNumbers((uint64_t)&L.getSemantics(),
|
|
|
|
(uint64_t)&R.getSemantics()))
|
|
|
|
return Res;
|
|
|
|
return cmpAPInt(L.bitcastToAPInt(), R.bitcastToAPInt());
|
|
|
|
}
|
|
|
|
|
2014-05-16 16:55:34 +08:00
|
|
|
int FunctionComparator::cmpStrings(StringRef L, StringRef R) const {
|
|
|
|
// Prevent heavy comparison, compare sizes first.
|
|
|
|
if (int Res = cmpNumbers(L.size(), R.size()))
|
|
|
|
return Res;
|
|
|
|
|
|
|
|
// Compare strings lexicographically only when it is necessary: only when
|
|
|
|
// strings are equal in size.
|
|
|
|
return L.compare(R);
|
|
|
|
}
|
|
|
|
|
|
|
|
int FunctionComparator::cmpAttrs(const AttributeSet L,
|
|
|
|
const AttributeSet R) const {
|
|
|
|
if (int Res = cmpNumbers(L.getNumSlots(), R.getNumSlots()))
|
|
|
|
return Res;
|
|
|
|
|
|
|
|
for (unsigned i = 0, e = L.getNumSlots(); i != e; ++i) {
|
|
|
|
AttributeSet::iterator LI = L.begin(i), LE = L.end(i), RI = R.begin(i),
|
|
|
|
RE = R.end(i);
|
|
|
|
for (; LI != LE && RI != RE; ++LI, ++RI) {
|
|
|
|
Attribute LA = *LI;
|
|
|
|
Attribute RA = *RI;
|
|
|
|
if (LA < RA)
|
|
|
|
return -1;
|
|
|
|
if (RA < LA)
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
if (LI != LE)
|
|
|
|
return 1;
|
|
|
|
if (RI != RE)
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-05-07 17:05:10 +08:00
|
|
|
/// Constants comparison:
|
|
|
|
/// 1. Check whether type of L constant could be losslessly bitcasted to R
|
|
|
|
/// type.
|
|
|
|
/// 2. Compare constant contents.
|
|
|
|
/// For more details see declaration comments.
|
|
|
|
int FunctionComparator::cmpConstants(const Constant *L, const Constant *R) {
|
|
|
|
|
|
|
|
Type *TyL = L->getType();
|
|
|
|
Type *TyR = R->getType();
|
|
|
|
|
|
|
|
// Check whether types are bitcastable. This part is just re-factored
|
|
|
|
// Type::canLosslesslyBitCastTo method, but instead of returning true/false,
|
|
|
|
// we also pack into result which type is "less" for us.
|
|
|
|
int TypesRes = cmpType(TyL, TyR);
|
|
|
|
if (TypesRes != 0) {
|
|
|
|
// Types are different, but check whether we can bitcast them.
|
|
|
|
if (!TyL->isFirstClassType()) {
|
|
|
|
if (TyR->isFirstClassType())
|
|
|
|
return -1;
|
|
|
|
// Neither TyL nor TyR are values of first class type. Return the result
|
|
|
|
// of comparing the types
|
|
|
|
return TypesRes;
|
|
|
|
}
|
|
|
|
if (!TyR->isFirstClassType()) {
|
|
|
|
if (TyL->isFirstClassType())
|
|
|
|
return 1;
|
|
|
|
return TypesRes;
|
|
|
|
}
|
|
|
|
|
|
|
|
// Vector -> Vector conversions are always lossless if the two vector types
|
|
|
|
// have the same size, otherwise not.
|
|
|
|
unsigned TyLWidth = 0;
|
|
|
|
unsigned TyRWidth = 0;
|
|
|
|
|
|
|
|
if (const VectorType *VecTyL = dyn_cast<VectorType>(TyL))
|
|
|
|
TyLWidth = VecTyL->getBitWidth();
|
|
|
|
if (const VectorType *VecTyR = dyn_cast<VectorType>(TyR))
|
|
|
|
TyRWidth = VecTyR->getBitWidth();
|
|
|
|
|
|
|
|
if (TyLWidth != TyRWidth)
|
|
|
|
return cmpNumbers(TyLWidth, TyRWidth);
|
|
|
|
|
|
|
|
// Zero bit-width means neither TyL nor TyR are vectors.
|
|
|
|
if (!TyLWidth) {
|
|
|
|
PointerType *PTyL = dyn_cast<PointerType>(TyL);
|
|
|
|
PointerType *PTyR = dyn_cast<PointerType>(TyR);
|
|
|
|
if (PTyL && PTyR) {
|
|
|
|
unsigned AddrSpaceL = PTyL->getAddressSpace();
|
|
|
|
unsigned AddrSpaceR = PTyR->getAddressSpace();
|
|
|
|
if (int Res = cmpNumbers(AddrSpaceL, AddrSpaceR))
|
|
|
|
return Res;
|
|
|
|
}
|
|
|
|
if (PTyL)
|
|
|
|
return 1;
|
|
|
|
if (PTyR)
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
// TyL and TyR aren't vectors, nor pointers. We don't know how to
|
|
|
|
// bitcast them.
|
|
|
|
return TypesRes;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// OK, types are bitcastable, now check constant contents.
|
|
|
|
|
|
|
|
if (L->isNullValue() && R->isNullValue())
|
|
|
|
return TypesRes;
|
|
|
|
if (L->isNullValue() && !R->isNullValue())
|
|
|
|
return 1;
|
|
|
|
if (!L->isNullValue() && R->isNullValue())
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
if (int Res = cmpNumbers(L->getValueID(), R->getValueID()))
|
|
|
|
return Res;
|
|
|
|
|
|
|
|
switch (L->getValueID()) {
|
|
|
|
case Value::UndefValueVal: return TypesRes;
|
|
|
|
case Value::ConstantIntVal: {
|
|
|
|
const APInt &LInt = cast<ConstantInt>(L)->getValue();
|
|
|
|
const APInt &RInt = cast<ConstantInt>(R)->getValue();
|
|
|
|
return cmpAPInt(LInt, RInt);
|
|
|
|
}
|
|
|
|
case Value::ConstantFPVal: {
|
|
|
|
const APFloat &LAPF = cast<ConstantFP>(L)->getValueAPF();
|
|
|
|
const APFloat &RAPF = cast<ConstantFP>(R)->getValueAPF();
|
|
|
|
return cmpAPFloat(LAPF, RAPF);
|
|
|
|
}
|
|
|
|
case Value::ConstantArrayVal: {
|
|
|
|
const ConstantArray *LA = cast<ConstantArray>(L);
|
|
|
|
const ConstantArray *RA = cast<ConstantArray>(R);
|
|
|
|
uint64_t NumElementsL = cast<ArrayType>(TyL)->getNumElements();
|
|
|
|
uint64_t NumElementsR = cast<ArrayType>(TyR)->getNumElements();
|
|
|
|
if (int Res = cmpNumbers(NumElementsL, NumElementsR))
|
|
|
|
return Res;
|
|
|
|
for (uint64_t i = 0; i < NumElementsL; ++i) {
|
|
|
|
if (int Res = cmpConstants(cast<Constant>(LA->getOperand(i)),
|
|
|
|
cast<Constant>(RA->getOperand(i))))
|
|
|
|
return Res;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
case Value::ConstantStructVal: {
|
|
|
|
const ConstantStruct *LS = cast<ConstantStruct>(L);
|
|
|
|
const ConstantStruct *RS = cast<ConstantStruct>(R);
|
|
|
|
unsigned NumElementsL = cast<StructType>(TyL)->getNumElements();
|
|
|
|
unsigned NumElementsR = cast<StructType>(TyR)->getNumElements();
|
|
|
|
if (int Res = cmpNumbers(NumElementsL, NumElementsR))
|
|
|
|
return Res;
|
|
|
|
for (unsigned i = 0; i != NumElementsL; ++i) {
|
|
|
|
if (int Res = cmpConstants(cast<Constant>(LS->getOperand(i)),
|
|
|
|
cast<Constant>(RS->getOperand(i))))
|
|
|
|
return Res;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
case Value::ConstantVectorVal: {
|
|
|
|
const ConstantVector *LV = cast<ConstantVector>(L);
|
|
|
|
const ConstantVector *RV = cast<ConstantVector>(R);
|
|
|
|
unsigned NumElementsL = cast<VectorType>(TyL)->getNumElements();
|
|
|
|
unsigned NumElementsR = cast<VectorType>(TyR)->getNumElements();
|
|
|
|
if (int Res = cmpNumbers(NumElementsL, NumElementsR))
|
|
|
|
return Res;
|
|
|
|
for (uint64_t i = 0; i < NumElementsL; ++i) {
|
|
|
|
if (int Res = cmpConstants(cast<Constant>(LV->getOperand(i)),
|
|
|
|
cast<Constant>(RV->getOperand(i))))
|
|
|
|
return Res;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
case Value::ConstantExprVal: {
|
|
|
|
const ConstantExpr *LE = cast<ConstantExpr>(L);
|
|
|
|
const ConstantExpr *RE = cast<ConstantExpr>(R);
|
|
|
|
unsigned NumOperandsL = LE->getNumOperands();
|
|
|
|
unsigned NumOperandsR = RE->getNumOperands();
|
|
|
|
if (int Res = cmpNumbers(NumOperandsL, NumOperandsR))
|
|
|
|
return Res;
|
|
|
|
for (unsigned i = 0; i < NumOperandsL; ++i) {
|
|
|
|
if (int Res = cmpConstants(cast<Constant>(LE->getOperand(i)),
|
|
|
|
cast<Constant>(RE->getOperand(i))))
|
|
|
|
return Res;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
case Value::FunctionVal:
|
|
|
|
case Value::GlobalVariableVal:
|
|
|
|
case Value::GlobalAliasVal:
|
|
|
|
default: // Unknown constant, cast L and R pointers to numbers and compare.
|
|
|
|
return cmpNumbers((uint64_t)L, (uint64_t)R);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2014-03-13 19:54:50 +08:00
|
|
|
/// cmpType - compares two types,
|
|
|
|
/// defines total ordering among the types set.
|
|
|
|
/// See method declaration comments for more details.
|
|
|
|
int FunctionComparator::cmpType(Type *TyL, Type *TyR) const {
|
2013-11-27 00:11:03 +08:00
|
|
|
|
2014-03-14 16:48:52 +08:00
|
|
|
PointerType *PTyL = dyn_cast<PointerType>(TyL);
|
|
|
|
PointerType *PTyR = dyn_cast<PointerType>(TyR);
|
2013-11-27 00:11:03 +08:00
|
|
|
|
2014-02-21 08:06:31 +08:00
|
|
|
if (DL) {
|
2014-03-14 16:48:52 +08:00
|
|
|
if (PTyL && PTyL->getAddressSpace() == 0) TyL = DL->getIntPtrType(TyL);
|
|
|
|
if (PTyR && PTyR->getAddressSpace() == 0) TyR = DL->getIntPtrType(TyR);
|
2013-11-27 00:11:03 +08:00
|
|
|
}
|
|
|
|
|
2014-03-13 19:54:50 +08:00
|
|
|
if (TyL == TyR)
|
|
|
|
return 0;
|
2013-11-10 09:44:37 +08:00
|
|
|
|
2014-03-13 19:54:50 +08:00
|
|
|
if (int Res = cmpNumbers(TyL->getTypeID(), TyR->getTypeID()))
|
|
|
|
return Res;
|
2009-06-12 16:04:51 +08:00
|
|
|
|
2014-03-13 19:54:50 +08:00
|
|
|
switch (TyL->getTypeID()) {
|
2010-05-13 13:48:45 +08:00
|
|
|
default:
|
|
|
|
llvm_unreachable("Unknown type!");
|
2010-07-07 15:48:00 +08:00
|
|
|
// Fall through in Release mode.
|
2010-05-13 13:48:45 +08:00
|
|
|
case Type::IntegerTyID:
|
2011-01-26 16:50:18 +08:00
|
|
|
case Type::VectorTyID:
|
2014-03-13 19:54:50 +08:00
|
|
|
// TyL == TyR would have returned true earlier.
|
|
|
|
return cmpNumbers((uint64_t)TyL, (uint64_t)TyR);
|
2010-05-13 13:48:45 +08:00
|
|
|
|
2009-06-12 16:04:51 +08:00
|
|
|
case Type::VoidTyID:
|
|
|
|
case Type::FloatTyID:
|
|
|
|
case Type::DoubleTyID:
|
|
|
|
case Type::X86_FP80TyID:
|
|
|
|
case Type::FP128TyID:
|
|
|
|
case Type::PPC_FP128TyID:
|
|
|
|
case Type::LabelTyID:
|
|
|
|
case Type::MetadataTyID:
|
2014-03-13 19:54:50 +08:00
|
|
|
return 0;
|
2009-06-12 16:04:51 +08:00
|
|
|
|
|
|
|
case Type::PointerTyID: {
|
2014-03-14 16:48:52 +08:00
|
|
|
assert(PTyL && PTyR && "Both types must be pointers here.");
|
|
|
|
return cmpNumbers(PTyL->getAddressSpace(), PTyR->getAddressSpace());
|
2009-06-12 16:04:51 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
case Type::StructTyID: {
|
2014-03-14 16:48:52 +08:00
|
|
|
StructType *STyL = cast<StructType>(TyL);
|
|
|
|
StructType *STyR = cast<StructType>(TyR);
|
|
|
|
if (STyL->getNumElements() != STyR->getNumElements())
|
|
|
|
return cmpNumbers(STyL->getNumElements(), STyR->getNumElements());
|
2009-06-12 16:04:51 +08:00
|
|
|
|
2014-03-14 16:48:52 +08:00
|
|
|
if (STyL->isPacked() != STyR->isPacked())
|
|
|
|
return cmpNumbers(STyL->isPacked(), STyR->isPacked());
|
2009-06-12 16:04:51 +08:00
|
|
|
|
2014-03-14 16:48:52 +08:00
|
|
|
for (unsigned i = 0, e = STyL->getNumElements(); i != e; ++i) {
|
|
|
|
if (int Res = cmpType(STyL->getElementType(i),
|
|
|
|
STyR->getElementType(i)))
|
2014-03-13 19:54:50 +08:00
|
|
|
return Res;
|
2009-06-12 16:04:51 +08:00
|
|
|
}
|
2014-03-13 19:54:50 +08:00
|
|
|
return 0;
|
2009-06-12 16:04:51 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
case Type::FunctionTyID: {
|
2014-03-14 16:48:52 +08:00
|
|
|
FunctionType *FTyL = cast<FunctionType>(TyL);
|
|
|
|
FunctionType *FTyR = cast<FunctionType>(TyR);
|
|
|
|
if (FTyL->getNumParams() != FTyR->getNumParams())
|
|
|
|
return cmpNumbers(FTyL->getNumParams(), FTyR->getNumParams());
|
2014-03-13 19:54:50 +08:00
|
|
|
|
2014-03-14 16:48:52 +08:00
|
|
|
if (FTyL->isVarArg() != FTyR->isVarArg())
|
|
|
|
return cmpNumbers(FTyL->isVarArg(), FTyR->isVarArg());
|
2009-06-12 16:04:51 +08:00
|
|
|
|
2014-03-14 16:48:52 +08:00
|
|
|
if (int Res = cmpType(FTyL->getReturnType(), FTyR->getReturnType()))
|
2014-03-13 19:54:50 +08:00
|
|
|
return Res;
|
2009-06-12 16:04:51 +08:00
|
|
|
|
2014-03-14 16:48:52 +08:00
|
|
|
for (unsigned i = 0, e = FTyL->getNumParams(); i != e; ++i) {
|
|
|
|
if (int Res = cmpType(FTyL->getParamType(i), FTyR->getParamType(i)))
|
2014-03-13 19:54:50 +08:00
|
|
|
return Res;
|
2009-06-12 16:04:51 +08:00
|
|
|
}
|
2014-03-13 19:54:50 +08:00
|
|
|
return 0;
|
2009-06-12 16:04:51 +08:00
|
|
|
}
|
|
|
|
|
2010-07-16 14:31:12 +08:00
|
|
|
case Type::ArrayTyID: {
|
2014-03-14 16:48:52 +08:00
|
|
|
ArrayType *ATyL = cast<ArrayType>(TyL);
|
|
|
|
ArrayType *ATyR = cast<ArrayType>(TyR);
|
|
|
|
if (ATyL->getNumElements() != ATyR->getNumElements())
|
|
|
|
return cmpNumbers(ATyL->getNumElements(), ATyR->getNumElements());
|
|
|
|
return cmpType(ATyL->getElementType(), ATyR->getElementType());
|
2009-06-12 16:04:51 +08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Determine whether the two operations are the same except that pointer-to-A
|
|
|
|
// and pointer-to-B are equivalent. This should be kept in sync with
|
|
|
|
// Instruction::isSameOperationAs.
|
2014-05-16 19:02:22 +08:00
|
|
|
// Read method declaration comments for more details.
|
|
|
|
int FunctionComparator::cmpOperation(const Instruction *L,
|
|
|
|
const Instruction *R) const {
|
2011-02-06 13:04:00 +08:00
|
|
|
// Differences from Instruction::isSameOperationAs:
|
|
|
|
// * replace type comparison with calls to isEquivalentType.
|
|
|
|
// * we test for I->hasSameSubclassOptionalData (nuw/nsw/tail) at the top
|
|
|
|
// * because of the above, we don't test for the tail bit on calls later on
|
2014-05-16 19:02:22 +08:00
|
|
|
if (int Res = cmpNumbers(L->getOpcode(), R->getOpcode()))
|
|
|
|
return Res;
|
|
|
|
|
|
|
|
if (int Res = cmpNumbers(L->getNumOperands(), R->getNumOperands()))
|
|
|
|
return Res;
|
|
|
|
|
|
|
|
if (int Res = cmpType(L->getType(), R->getType()))
|
|
|
|
return Res;
|
|
|
|
|
|
|
|
if (int Res = cmpNumbers(L->getRawSubclassOptionalData(),
|
|
|
|
R->getRawSubclassOptionalData()))
|
|
|
|
return Res;
|
2009-06-12 16:04:51 +08:00
|
|
|
|
|
|
|
// We have two instructions of identical opcode and #operands. Check to see
|
|
|
|
// if all operands are the same type
|
2014-05-16 19:02:22 +08:00
|
|
|
for (unsigned i = 0, e = L->getNumOperands(); i != e; ++i) {
|
|
|
|
if (int Res =
|
|
|
|
cmpType(L->getOperand(i)->getType(), R->getOperand(i)->getType()))
|
|
|
|
return Res;
|
|
|
|
}
|
2009-06-12 16:04:51 +08:00
|
|
|
|
|
|
|
// Check special state that is a part of some instructions.
|
2014-05-16 19:02:22 +08:00
|
|
|
if (const LoadInst *LI = dyn_cast<LoadInst>(L)) {
|
|
|
|
if (int Res = cmpNumbers(LI->isVolatile(), cast<LoadInst>(R)->isVolatile()))
|
|
|
|
return Res;
|
|
|
|
if (int Res =
|
|
|
|
cmpNumbers(LI->getAlignment(), cast<LoadInst>(R)->getAlignment()))
|
|
|
|
return Res;
|
|
|
|
if (int Res =
|
|
|
|
cmpNumbers(LI->getOrdering(), cast<LoadInst>(R)->getOrdering()))
|
|
|
|
return Res;
|
|
|
|
return cmpNumbers(LI->getSynchScope(), cast<LoadInst>(R)->getSynchScope());
|
|
|
|
}
|
|
|
|
if (const StoreInst *SI = dyn_cast<StoreInst>(L)) {
|
|
|
|
if (int Res =
|
|
|
|
cmpNumbers(SI->isVolatile(), cast<StoreInst>(R)->isVolatile()))
|
|
|
|
return Res;
|
|
|
|
if (int Res =
|
|
|
|
cmpNumbers(SI->getAlignment(), cast<StoreInst>(R)->getAlignment()))
|
|
|
|
return Res;
|
|
|
|
if (int Res =
|
|
|
|
cmpNumbers(SI->getOrdering(), cast<StoreInst>(R)->getOrdering()))
|
|
|
|
return Res;
|
|
|
|
return cmpNumbers(SI->getSynchScope(), cast<StoreInst>(R)->getSynchScope());
|
|
|
|
}
|
|
|
|
if (const CmpInst *CI = dyn_cast<CmpInst>(L))
|
|
|
|
return cmpNumbers(CI->getPredicate(), cast<CmpInst>(R)->getPredicate());
|
|
|
|
if (const CallInst *CI = dyn_cast<CallInst>(L)) {
|
|
|
|
if (int Res = cmpNumbers(CI->getCallingConv(),
|
|
|
|
cast<CallInst>(R)->getCallingConv()))
|
|
|
|
return Res;
|
|
|
|
return cmpAttrs(CI->getAttributes(), cast<CallInst>(R)->getAttributes());
|
|
|
|
}
|
|
|
|
if (const InvokeInst *CI = dyn_cast<InvokeInst>(L)) {
|
|
|
|
if (int Res = cmpNumbers(CI->getCallingConv(),
|
|
|
|
cast<InvokeInst>(R)->getCallingConv()))
|
|
|
|
return Res;
|
|
|
|
return cmpAttrs(CI->getAttributes(), cast<InvokeInst>(R)->getAttributes());
|
|
|
|
}
|
|
|
|
if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(L)) {
|
|
|
|
ArrayRef<unsigned> LIndices = IVI->getIndices();
|
|
|
|
ArrayRef<unsigned> RIndices = cast<InsertValueInst>(R)->getIndices();
|
|
|
|
if (int Res = cmpNumbers(LIndices.size(), RIndices.size()))
|
|
|
|
return Res;
|
|
|
|
for (size_t i = 0, e = LIndices.size(); i != e; ++i) {
|
|
|
|
if (int Res = cmpNumbers(LIndices[i], RIndices[i]))
|
|
|
|
return Res;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(L)) {
|
|
|
|
ArrayRef<unsigned> LIndices = EVI->getIndices();
|
|
|
|
ArrayRef<unsigned> RIndices = cast<ExtractValueInst>(R)->getIndices();
|
|
|
|
if (int Res = cmpNumbers(LIndices.size(), RIndices.size()))
|
|
|
|
return Res;
|
|
|
|
for (size_t i = 0, e = LIndices.size(); i != e; ++i) {
|
|
|
|
if (int Res = cmpNumbers(LIndices[i], RIndices[i]))
|
|
|
|
return Res;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (const FenceInst *FI = dyn_cast<FenceInst>(L)) {
|
|
|
|
if (int Res =
|
|
|
|
cmpNumbers(FI->getOrdering(), cast<FenceInst>(R)->getOrdering()))
|
|
|
|
return Res;
|
|
|
|
return cmpNumbers(FI->getSynchScope(), cast<FenceInst>(R)->getSynchScope());
|
|
|
|
}
|
|
|
|
|
|
|
|
if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(L)) {
|
|
|
|
if (int Res = cmpNumbers(CXI->isVolatile(),
|
|
|
|
cast<AtomicCmpXchgInst>(R)->isVolatile()))
|
|
|
|
return Res;
|
IR: add "cmpxchg weak" variant to support permitted failure.
This commit adds a weak variant of the cmpxchg operation, as described
in C++11. A cmpxchg instruction with this modifier is permitted to
fail to store, even if the comparison indicated it should.
As a result, cmpxchg instructions must return a flag indicating
success in addition to their original iN value loaded. Thus, for
uniformity *all* cmpxchg instructions now return "{ iN, i1 }". The
second flag is 1 when the store succeeded.
At the DAG level, a new ATOMIC_CMP_SWAP_WITH_SUCCESS node has been
added as the natural representation for the new cmpxchg instructions.
It is a strong cmpxchg.
By default this gets Expanded to the existing ATOMIC_CMP_SWAP during
Legalization, so existing backends should see no change in behaviour.
If they wish to deal with the enhanced node instead, they can call
setOperationAction on it. Beware: as a node with 2 results, it cannot
be selected from TableGen.
Currently, no use is made of the extra information provided in this
patch. Test updates are almost entirely adapting the input IR to the
new scheme.
Summary for out of tree users:
------------------------------
+ Legacy Bitcode files are upgraded during read.
+ Legacy assembly IR files will be invalid.
+ Front-ends must adapt to different type for "cmpxchg".
+ Backends should be unaffected by default.
llvm-svn: 210903
2014-06-13 22:24:07 +08:00
|
|
|
if (int Res = cmpNumbers(CXI->isWeak(),
|
|
|
|
cast<AtomicCmpXchgInst>(R)->isWeak()))
|
|
|
|
return Res;
|
2014-05-16 19:02:22 +08:00
|
|
|
if (int Res = cmpNumbers(CXI->getSuccessOrdering(),
|
|
|
|
cast<AtomicCmpXchgInst>(R)->getSuccessOrdering()))
|
|
|
|
return Res;
|
|
|
|
if (int Res = cmpNumbers(CXI->getFailureOrdering(),
|
|
|
|
cast<AtomicCmpXchgInst>(R)->getFailureOrdering()))
|
|
|
|
return Res;
|
|
|
|
return cmpNumbers(CXI->getSynchScope(),
|
|
|
|
cast<AtomicCmpXchgInst>(R)->getSynchScope());
|
|
|
|
}
|
|
|
|
if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(L)) {
|
|
|
|
if (int Res = cmpNumbers(RMWI->getOperation(),
|
|
|
|
cast<AtomicRMWInst>(R)->getOperation()))
|
|
|
|
return Res;
|
|
|
|
if (int Res = cmpNumbers(RMWI->isVolatile(),
|
|
|
|
cast<AtomicRMWInst>(R)->isVolatile()))
|
|
|
|
return Res;
|
|
|
|
if (int Res = cmpNumbers(RMWI->getOrdering(),
|
|
|
|
cast<AtomicRMWInst>(R)->getOrdering()))
|
|
|
|
return Res;
|
|
|
|
return cmpNumbers(RMWI->getSynchScope(),
|
|
|
|
cast<AtomicRMWInst>(R)->getSynchScope());
|
|
|
|
}
|
|
|
|
return 0;
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Determine whether two GEP operations perform the same underlying arithmetic.
|
2014-05-16 19:55:02 +08:00
|
|
|
// Read method declaration comments for more details.
|
|
|
|
int FunctionComparator::cmpGEP(const GEPOperator *GEPL,
|
|
|
|
const GEPOperator *GEPR) {
|
|
|
|
|
|
|
|
unsigned int ASL = GEPL->getPointerAddressSpace();
|
|
|
|
unsigned int ASR = GEPR->getPointerAddressSpace();
|
|
|
|
|
|
|
|
if (int Res = cmpNumbers(ASL, ASR))
|
|
|
|
return Res;
|
2013-11-10 09:44:37 +08:00
|
|
|
|
2014-05-16 19:55:02 +08:00
|
|
|
// When we have target data, we can reduce the GEP down to the value in bytes
|
|
|
|
// added to the address.
|
2014-02-21 08:06:31 +08:00
|
|
|
if (DL) {
|
2014-05-16 19:55:02 +08:00
|
|
|
unsigned BitWidth = DL->getPointerSizeInBits(ASL);
|
|
|
|
APInt OffsetL(BitWidth, 0), OffsetR(BitWidth, 0);
|
|
|
|
if (GEPL->accumulateConstantOffset(*DL, OffsetL) &&
|
|
|
|
GEPR->accumulateConstantOffset(*DL, OffsetR))
|
|
|
|
return cmpAPInt(OffsetL, OffsetR);
|
2010-05-13 13:48:45 +08:00
|
|
|
}
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2014-05-16 19:55:02 +08:00
|
|
|
if (int Res = cmpNumbers((uint64_t)GEPL->getPointerOperand()->getType(),
|
|
|
|
(uint64_t)GEPR->getPointerOperand()->getType()))
|
|
|
|
return Res;
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2014-05-16 19:55:02 +08:00
|
|
|
if (int Res = cmpNumbers(GEPL->getNumOperands(), GEPR->getNumOperands()))
|
|
|
|
return Res;
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2014-05-16 19:55:02 +08:00
|
|
|
for (unsigned i = 0, e = GEPL->getNumOperands(); i != e; ++i) {
|
|
|
|
if (int Res = cmpValues(GEPL->getOperand(i), GEPR->getOperand(i)))
|
|
|
|
return Res;
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
|
2014-05-16 19:55:02 +08:00
|
|
|
return 0;
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
|
2014-05-07 19:11:39 +08:00
|
|
|
/// Compare two values used by the two functions under pair-wise comparison. If
|
|
|
|
/// this is the first time the values are seen, they're added to the mapping so
|
|
|
|
/// that we will detect mismatches on next use.
|
|
|
|
/// See comments in declaration for more details.
|
|
|
|
int FunctionComparator::cmpValues(const Value *L, const Value *R) {
|
|
|
|
// Catch self-reference case.
|
|
|
|
if (L == F1) {
|
|
|
|
if (R == F2)
|
|
|
|
return 0;
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
if (R == F2) {
|
|
|
|
if (L == F1)
|
|
|
|
return 0;
|
|
|
|
return 1;
|
2011-01-27 16:38:19 +08:00
|
|
|
}
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2014-05-07 19:11:39 +08:00
|
|
|
const Constant *ConstL = dyn_cast<Constant>(L);
|
|
|
|
const Constant *ConstR = dyn_cast<Constant>(R);
|
|
|
|
if (ConstL && ConstR) {
|
|
|
|
if (L == R)
|
|
|
|
return 0;
|
|
|
|
return cmpConstants(ConstL, ConstR);
|
|
|
|
}
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2014-05-07 19:11:39 +08:00
|
|
|
if (ConstL)
|
|
|
|
return 1;
|
|
|
|
if (ConstR)
|
|
|
|
return -1;
|
2010-05-13 13:48:45 +08:00
|
|
|
|
2014-05-07 19:11:39 +08:00
|
|
|
const InlineAsm *InlineAsmL = dyn_cast<InlineAsm>(L);
|
|
|
|
const InlineAsm *InlineAsmR = dyn_cast<InlineAsm>(R);
|
2010-05-13 13:48:45 +08:00
|
|
|
|
2014-05-07 19:11:39 +08:00
|
|
|
if (InlineAsmL && InlineAsmR)
|
|
|
|
return cmpNumbers((uint64_t)L, (uint64_t)R);
|
|
|
|
if (InlineAsmL)
|
|
|
|
return 1;
|
|
|
|
if (InlineAsmR)
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
auto LeftSN = sn_mapL.insert(std::make_pair(L, sn_mapL.size())),
|
|
|
|
RightSN = sn_mapR.insert(std::make_pair(R, sn_mapR.size()));
|
|
|
|
|
|
|
|
return cmpNumbers(LeftSN.first->second, RightSN.first->second);
|
|
|
|
}
|
2011-01-28 16:43:14 +08:00
|
|
|
// Test whether two basic blocks have equivalent behaviour.
|
|
|
|
bool FunctionComparator::compare(const BasicBlock *BB1, const BasicBlock *BB2) {
|
2010-08-02 13:23:03 +08:00
|
|
|
BasicBlock::const_iterator F1I = BB1->begin(), F1E = BB1->end();
|
|
|
|
BasicBlock::const_iterator F2I = BB2->begin(), F2E = BB2->end();
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2010-05-13 13:48:45 +08:00
|
|
|
do {
|
2011-01-28 16:43:14 +08:00
|
|
|
if (!enumerate(F1I, F2I))
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (const GetElementPtrInst *GEP1 = dyn_cast<GetElementPtrInst>(F1I)) {
|
|
|
|
const GetElementPtrInst *GEP2 = dyn_cast<GetElementPtrInst>(F2I);
|
|
|
|
if (!GEP2)
|
|
|
|
return false;
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
if (!enumerate(GEP1->getPointerOperand(), GEP2->getPointerOperand()))
|
2010-05-13 14:45:13 +08:00
|
|
|
return false;
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2010-05-13 13:48:45 +08:00
|
|
|
if (!isEquivalentGEP(GEP1, GEP2))
|
2010-05-13 14:45:13 +08:00
|
|
|
return false;
|
2010-05-13 13:48:45 +08:00
|
|
|
} else {
|
2010-08-02 13:23:03 +08:00
|
|
|
if (!isEquivalentOperation(F1I, F2I))
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
assert(F1I->getNumOperands() == F2I->getNumOperands());
|
|
|
|
for (unsigned i = 0, e = F1I->getNumOperands(); i != e; ++i) {
|
|
|
|
Value *OpF1 = F1I->getOperand(i);
|
|
|
|
Value *OpF2 = F2I->getOperand(i);
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
if (!enumerate(OpF1, OpF2))
|
2010-05-13 14:45:13 +08:00
|
|
|
return false;
|
2010-05-13 13:48:45 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (OpF1->getValueID() != OpF2->getValueID() ||
|
|
|
|
!isEquivalentType(OpF1->getType(), OpF2->getType()))
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
++F1I, ++F2I;
|
|
|
|
} while (F1I != F1E && F2I != F2E);
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
return F1I == F1E && F2I == F2E;
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Test whether the two functions have equivalent behaviour.
|
|
|
|
bool FunctionComparator::compare() {
|
2008-11-02 13:52:50 +08:00
|
|
|
// We need to recheck everything, but check the things that weren't included
|
|
|
|
// in the hash first.
|
|
|
|
|
2014-05-07 19:11:39 +08:00
|
|
|
sn_mapL.clear();
|
|
|
|
sn_mapR.clear();
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (F1->getAttributes() != F2->getAttributes())
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (F1->hasGC() != F2->hasGC())
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (F1->hasGC() && F1->getGC() != F2->getGC())
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (F1->hasSection() != F2->hasSection())
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (F1->hasSection() && F1->getSection() != F2->getSection())
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (F1->isVarArg() != F2->isVarArg())
|
2009-06-12 16:04:51 +08:00
|
|
|
return false;
|
|
|
|
|
2008-11-02 13:52:50 +08:00
|
|
|
// TODO: if it's internal and only used in direct calls, we could handle this
|
|
|
|
// case too.
|
2010-08-02 13:23:03 +08:00
|
|
|
if (F1->getCallingConv() != F2->getCallingConv())
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
if (!isEquivalentType(F1->getFunctionType(), F2->getFunctionType()))
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
assert(F1->arg_size() == F2->arg_size() &&
|
2010-09-07 09:42:10 +08:00
|
|
|
"Identically typed functions have different numbers of args!");
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2010-05-13 13:48:45 +08:00
|
|
|
// Visit the arguments so that they get enumerated in the order they're
|
|
|
|
// passed in.
|
2010-08-02 13:23:03 +08:00
|
|
|
for (Function::const_arg_iterator f1i = F1->arg_begin(),
|
|
|
|
f2i = F2->arg_begin(), f1e = F1->arg_end(); f1i != f1e; ++f1i, ++f2i) {
|
2011-01-28 16:43:14 +08:00
|
|
|
if (!enumerate(f1i, f2i))
|
2010-09-07 09:42:10 +08:00
|
|
|
llvm_unreachable("Arguments repeat!");
|
2010-05-13 13:48:45 +08:00
|
|
|
}
|
2008-11-02 13:52:50 +08:00
|
|
|
|
2010-08-08 13:04:23 +08:00
|
|
|
// We do a CFG-ordered walk since the actual ordering of the blocks in the
|
|
|
|
// linked list is immaterial. Our walk starts at the entry block for both
|
2010-08-02 13:23:03 +08:00
|
|
|
// functions, then takes each block from each terminator in order. As an
|
|
|
|
// artifact, this also means that unreachable blocks are ignored.
|
|
|
|
SmallVector<const BasicBlock *, 8> F1BBs, F2BBs;
|
|
|
|
SmallSet<const BasicBlock *, 128> VisitedBBs; // in terms of F1.
|
2010-08-06 15:21:30 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
F1BBs.push_back(&F1->getEntryBlock());
|
|
|
|
F2BBs.push_back(&F2->getEntryBlock());
|
2010-08-06 15:21:30 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
VisitedBBs.insert(F1BBs[0]);
|
|
|
|
while (!F1BBs.empty()) {
|
|
|
|
const BasicBlock *F1BB = F1BBs.pop_back_val();
|
|
|
|
const BasicBlock *F2BB = F2BBs.pop_back_val();
|
2010-08-06 15:21:30 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
if (!enumerate(F1BB, F2BB) || !compare(F1BB, F2BB))
|
2008-11-02 13:52:50 +08:00
|
|
|
return false;
|
2010-08-06 15:21:30 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
const TerminatorInst *F1TI = F1BB->getTerminator();
|
|
|
|
const TerminatorInst *F2TI = F2BB->getTerminator();
|
2010-08-06 15:21:30 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
assert(F1TI->getNumSuccessors() == F2TI->getNumSuccessors());
|
|
|
|
for (unsigned i = 0, e = F1TI->getNumSuccessors(); i != e; ++i) {
|
|
|
|
if (!VisitedBBs.insert(F1TI->getSuccessor(i)))
|
2010-05-13 14:45:13 +08:00
|
|
|
continue;
|
2010-08-06 15:21:30 +08:00
|
|
|
|
2010-08-02 13:23:03 +08:00
|
|
|
F1BBs.push_back(F1TI->getSuccessor(i));
|
|
|
|
F2BBs.push_back(F2TI->getSuccessor(i));
|
2010-05-13 13:48:45 +08:00
|
|
|
}
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
2011-01-28 15:36:21 +08:00
|
|
|
namespace {
|
|
|
|
|
|
|
|
/// MergeFunctions finds functions which will generate identical machine code,
|
|
|
|
/// by considering all pointer types to be equivalent. Once identified,
|
|
|
|
/// MergeFunctions will fold them by replacing a call to one to a call to a
|
|
|
|
/// bitcast of the other.
|
|
|
|
///
|
|
|
|
class MergeFunctions : public ModulePass {
|
|
|
|
public:
|
|
|
|
static char ID;
|
|
|
|
MergeFunctions()
|
|
|
|
: ModulePass(ID), HasGlobalAliases(false) {
|
|
|
|
initializeMergeFunctionsPass(*PassRegistry::getPassRegistry());
|
|
|
|
}
|
|
|
|
|
2014-03-05 17:10:37 +08:00
|
|
|
bool runOnModule(Module &M) override;
|
2011-01-28 15:36:21 +08:00
|
|
|
|
|
|
|
private:
|
|
|
|
typedef DenseSet<ComparableFunction> FnSetType;
|
|
|
|
|
|
|
|
/// A work queue of functions that may have been modified and should be
|
|
|
|
/// analyzed again.
|
|
|
|
std::vector<WeakVH> Deferred;
|
|
|
|
|
|
|
|
/// Insert a ComparableFunction into the FnSet, or merge it away if it's
|
|
|
|
/// equal to one that's already present.
|
2011-01-28 16:43:14 +08:00
|
|
|
bool insert(ComparableFunction &NewF);
|
2011-01-28 15:36:21 +08:00
|
|
|
|
|
|
|
/// Remove a Function from the FnSet and queue it up for a second sweep of
|
|
|
|
/// analysis.
|
2011-01-28 16:43:14 +08:00
|
|
|
void remove(Function *F);
|
2011-01-28 15:36:21 +08:00
|
|
|
|
|
|
|
/// Find the functions that use this Value and remove them from FnSet and
|
|
|
|
/// queue the functions.
|
2011-01-28 16:43:14 +08:00
|
|
|
void removeUsers(Value *V);
|
2011-01-28 15:36:21 +08:00
|
|
|
|
|
|
|
/// Replace all direct calls of Old with calls of New. Will bitcast New if
|
|
|
|
/// necessary to make types match.
|
|
|
|
void replaceDirectCallers(Function *Old, Function *New);
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Merge two equivalent functions. Upon completion, G may be deleted, or may
|
|
|
|
/// be converted into a thunk. In either case, it should never be visited
|
|
|
|
/// again.
|
|
|
|
void mergeTwoFunctions(Function *F, Function *G);
|
2011-01-28 15:36:21 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Replace G with a thunk or an alias to F. Deletes G.
|
|
|
|
void writeThunkOrAlias(Function *F, Function *G);
|
2011-01-28 15:36:21 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Replace G with a simple tail call to bitcast(F). Also replace direct uses
|
|
|
|
/// of G with bitcast(F). Deletes G.
|
|
|
|
void writeThunk(Function *F, Function *G);
|
2011-01-28 15:36:21 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// Replace G with an alias to F. Deletes G.
|
|
|
|
void writeAlias(Function *F, Function *G);
|
2011-01-28 15:36:21 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
/// The set of all distinct functions. Use the insert() and remove() methods
|
|
|
|
/// to modify it.
|
2011-01-28 15:36:21 +08:00
|
|
|
FnSetType FnSet;
|
|
|
|
|
2012-10-09 00:38:25 +08:00
|
|
|
/// DataLayout for more accurate GEP comparisons. May be NULL.
|
2014-02-25 22:24:11 +08:00
|
|
|
const DataLayout *DL;
|
2011-01-28 15:36:21 +08:00
|
|
|
|
|
|
|
/// Whether or not the target supports global aliases.
|
|
|
|
bool HasGlobalAliases;
|
|
|
|
};
|
|
|
|
|
|
|
|
} // end anonymous namespace
|
|
|
|
|
|
|
|
char MergeFunctions::ID = 0;
|
|
|
|
INITIALIZE_PASS(MergeFunctions, "mergefunc", "Merge Functions", false, false)
|
|
|
|
|
|
|
|
ModulePass *llvm::createMergeFunctionsPass() {
|
|
|
|
return new MergeFunctions();
|
|
|
|
}
|
|
|
|
|
|
|
|
bool MergeFunctions::runOnModule(Module &M) {
|
|
|
|
bool Changed = false;
|
2014-02-26 01:30:31 +08:00
|
|
|
DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
|
2014-04-25 13:29:35 +08:00
|
|
|
DL = DLP ? &DLP->getDataLayout() : nullptr;
|
2011-01-28 15:36:21 +08:00
|
|
|
|
|
|
|
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
|
|
|
|
if (!I->isDeclaration() && !I->hasAvailableExternallyLinkage())
|
|
|
|
Deferred.push_back(WeakVH(I));
|
|
|
|
}
|
|
|
|
FnSet.resize(Deferred.size());
|
|
|
|
|
|
|
|
do {
|
|
|
|
std::vector<WeakVH> Worklist;
|
|
|
|
Deferred.swap(Worklist);
|
|
|
|
|
|
|
|
DEBUG(dbgs() << "size of module: " << M.size() << '\n');
|
|
|
|
DEBUG(dbgs() << "size of worklist: " << Worklist.size() << '\n');
|
|
|
|
|
|
|
|
// Insert only strong functions and merge them. Strong function merging
|
|
|
|
// always deletes one of them.
|
|
|
|
for (std::vector<WeakVH>::iterator I = Worklist.begin(),
|
|
|
|
E = Worklist.end(); I != E; ++I) {
|
|
|
|
if (!*I) continue;
|
|
|
|
Function *F = cast<Function>(*I);
|
|
|
|
if (!F->isDeclaration() && !F->hasAvailableExternallyLinkage() &&
|
|
|
|
!F->mayBeOverridden()) {
|
2014-02-21 08:06:31 +08:00
|
|
|
ComparableFunction CF = ComparableFunction(F, DL);
|
2011-01-28 16:43:14 +08:00
|
|
|
Changed |= insert(CF);
|
2011-01-28 15:36:21 +08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Insert only weak functions and merge them. By doing these second we
|
|
|
|
// create thunks to the strong function when possible. When two weak
|
|
|
|
// functions are identical, we create a new strong function with two weak
|
|
|
|
// weak thunks to it which are identical but not mergable.
|
|
|
|
for (std::vector<WeakVH>::iterator I = Worklist.begin(),
|
|
|
|
E = Worklist.end(); I != E; ++I) {
|
|
|
|
if (!*I) continue;
|
|
|
|
Function *F = cast<Function>(*I);
|
|
|
|
if (!F->isDeclaration() && !F->hasAvailableExternallyLinkage() &&
|
|
|
|
F->mayBeOverridden()) {
|
2014-02-21 08:06:31 +08:00
|
|
|
ComparableFunction CF = ComparableFunction(F, DL);
|
2011-01-28 16:43:14 +08:00
|
|
|
Changed |= insert(CF);
|
2011-01-28 15:36:21 +08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
DEBUG(dbgs() << "size of FnSet: " << FnSet.size() << '\n');
|
|
|
|
} while (!Deferred.empty());
|
|
|
|
|
|
|
|
FnSet.clear();
|
|
|
|
|
|
|
|
return Changed;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool DenseMapInfo<ComparableFunction>::isEqual(const ComparableFunction &LHS,
|
|
|
|
const ComparableFunction &RHS) {
|
|
|
|
if (LHS.getFunc() == RHS.getFunc() &&
|
|
|
|
LHS.getHash() == RHS.getHash())
|
|
|
|
return true;
|
|
|
|
if (!LHS.getFunc() || !RHS.getFunc())
|
|
|
|
return false;
|
2011-02-09 14:32:02 +08:00
|
|
|
|
|
|
|
// One of these is a special "underlying pointer comparison only" object.
|
2014-02-21 08:06:31 +08:00
|
|
|
if (LHS.getDataLayout() == ComparableFunction::LookupOnly ||
|
|
|
|
RHS.getDataLayout() == ComparableFunction::LookupOnly)
|
2011-02-09 14:32:02 +08:00
|
|
|
return false;
|
|
|
|
|
2014-02-21 08:06:31 +08:00
|
|
|
assert(LHS.getDataLayout() == RHS.getDataLayout() &&
|
2011-01-28 15:36:21 +08:00
|
|
|
"Comparing functions for different targets");
|
|
|
|
|
2014-02-21 08:06:31 +08:00
|
|
|
return FunctionComparator(LHS.getDataLayout(), LHS.getFunc(),
|
2011-02-02 13:31:01 +08:00
|
|
|
RHS.getFunc()).compare();
|
2011-01-28 15:36:21 +08:00
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Replace direct callers of Old with New.
|
2011-01-25 16:56:50 +08:00
|
|
|
void MergeFunctions::replaceDirectCallers(Function *Old, Function *New) {
|
|
|
|
Constant *BitcastNew = ConstantExpr::getBitCast(New, Old->getType());
|
2014-03-09 11:16:01 +08:00
|
|
|
for (auto UI = Old->use_begin(), UE = Old->use_end(); UI != UE;) {
|
|
|
|
Use *U = &*UI;
|
2011-01-25 16:56:50 +08:00
|
|
|
++UI;
|
2014-03-09 11:16:01 +08:00
|
|
|
CallSite CS(U->getUser());
|
|
|
|
if (CS && CS.isCallee(U)) {
|
2011-01-28 16:43:14 +08:00
|
|
|
remove(CS.getInstruction()->getParent()->getParent());
|
2014-03-09 11:16:01 +08:00
|
|
|
U->set(BitcastNew);
|
2011-01-25 16:56:50 +08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Replace G with an alias to F if possible, or else a thunk to F. Deletes G.
|
|
|
|
void MergeFunctions::writeThunkOrAlias(Function *F, Function *G) {
|
2011-01-25 16:56:50 +08:00
|
|
|
if (HasGlobalAliases && G->hasUnnamedAddr()) {
|
|
|
|
if (G->hasExternalLinkage() || G->hasLocalLinkage() ||
|
|
|
|
G->hasWeakLinkage()) {
|
2011-01-28 16:43:14 +08:00
|
|
|
writeAlias(F, G);
|
2011-01-25 16:56:50 +08:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
writeThunk(F, G);
|
2011-01-25 16:56:50 +08:00
|
|
|
}
|
|
|
|
|
2013-09-17 17:36:11 +08:00
|
|
|
// Helper for writeThunk,
|
|
|
|
// Selects proper bitcast operation,
|
2014-01-25 01:20:08 +08:00
|
|
|
// but a bit simpler then CastInst::getCastOpcode.
|
2014-05-01 01:53:04 +08:00
|
|
|
static Value *createCast(IRBuilder<false> &Builder, Value *V, Type *DestTy) {
|
2013-09-17 17:36:11 +08:00
|
|
|
Type *SrcTy = V->getType();
|
2014-05-01 01:53:04 +08:00
|
|
|
if (SrcTy->isStructTy()) {
|
|
|
|
assert(DestTy->isStructTy());
|
|
|
|
assert(SrcTy->getStructNumElements() == DestTy->getStructNumElements());
|
|
|
|
Value *Result = UndefValue::get(DestTy);
|
|
|
|
for (unsigned int I = 0, E = SrcTy->getStructNumElements(); I < E; ++I) {
|
|
|
|
Value *Element = createCast(
|
|
|
|
Builder, Builder.CreateExtractValue(V, ArrayRef<unsigned int>(I)),
|
|
|
|
DestTy->getStructElementType(I));
|
|
|
|
|
|
|
|
Result =
|
|
|
|
Builder.CreateInsertValue(Result, Element, ArrayRef<unsigned int>(I));
|
|
|
|
}
|
|
|
|
return Result;
|
|
|
|
}
|
|
|
|
assert(!DestTy->isStructTy());
|
2013-09-17 17:36:11 +08:00
|
|
|
if (SrcTy->isIntegerTy() && DestTy->isPointerTy())
|
|
|
|
return Builder.CreateIntToPtr(V, DestTy);
|
|
|
|
else if (SrcTy->isPointerTy() && DestTy->isIntegerTy())
|
|
|
|
return Builder.CreatePtrToInt(V, DestTy);
|
|
|
|
else
|
|
|
|
return Builder.CreateBitCast(V, DestTy);
|
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Replace G with a simple tail call to bitcast(F). Also replace direct uses
|
|
|
|
// of G with bitcast(F). Deletes G.
|
|
|
|
void MergeFunctions::writeThunk(Function *F, Function *G) {
|
2010-05-13 13:48:45 +08:00
|
|
|
if (!G->mayBeOverridden()) {
|
|
|
|
// Redirect direct callers of G to F.
|
2011-01-25 16:56:50 +08:00
|
|
|
replaceDirectCallers(G, F);
|
2010-05-13 13:48:45 +08:00
|
|
|
}
|
|
|
|
|
2010-09-07 09:42:10 +08:00
|
|
|
// If G was internal then we may have replaced all uses of G with F. If so,
|
2010-08-06 15:21:30 +08:00
|
|
|
// stop here and delete G. There's no need for a thunk.
|
|
|
|
if (G->hasLocalLinkage() && G->use_empty()) {
|
|
|
|
G->eraseFromParent();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
2009-06-12 23:56:56 +08:00
|
|
|
Function *NewG = Function::Create(G->getFunctionType(), G->getLinkage(), "",
|
|
|
|
G->getParent());
|
2009-08-14 05:58:54 +08:00
|
|
|
BasicBlock *BB = BasicBlock::Create(F->getContext(), "", NewG);
|
2010-08-08 13:04:23 +08:00
|
|
|
IRBuilder<false> Builder(BB);
|
2009-06-12 16:04:51 +08:00
|
|
|
|
2010-05-13 13:48:45 +08:00
|
|
|
SmallVector<Value *, 16> Args;
|
2009-06-12 16:04:51 +08:00
|
|
|
unsigned i = 0;
|
2011-07-18 12:54:35 +08:00
|
|
|
FunctionType *FFTy = F->getFunctionType();
|
2009-06-12 16:04:51 +08:00
|
|
|
for (Function::arg_iterator AI = NewG->arg_begin(), AE = NewG->arg_end();
|
|
|
|
AI != AE; ++AI) {
|
2013-09-17 17:36:11 +08:00
|
|
|
Args.push_back(createCast(Builder, (Value*)AI, FFTy->getParamType(i)));
|
2009-06-12 16:04:51 +08:00
|
|
|
++i;
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
|
2011-07-15 16:37:34 +08:00
|
|
|
CallInst *CI = Builder.CreateCall(F, Args);
|
2009-06-12 16:04:51 +08:00
|
|
|
CI->setTailCall();
|
2009-06-13 00:04:00 +08:00
|
|
|
CI->setCallingConv(F->getCallingConv());
|
2010-01-05 21:12:22 +08:00
|
|
|
if (NewG->getReturnType()->isVoidTy()) {
|
2010-08-08 13:04:23 +08:00
|
|
|
Builder.CreateRetVoid();
|
2009-06-12 16:04:51 +08:00
|
|
|
} else {
|
2013-09-17 17:36:11 +08:00
|
|
|
Builder.CreateRet(createCast(Builder, CI, NewG->getReturnType()));
|
2008-11-03 00:46:26 +08:00
|
|
|
}
|
|
|
|
|
2009-06-12 16:04:51 +08:00
|
|
|
NewG->copyAttributesFrom(G);
|
|
|
|
NewG->takeName(G);
|
2011-01-28 16:43:14 +08:00
|
|
|
removeUsers(G);
|
2009-06-12 16:04:51 +08:00
|
|
|
G->replaceAllUsesWith(NewG);
|
|
|
|
G->eraseFromParent();
|
2010-09-07 09:42:10 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
DEBUG(dbgs() << "writeThunk: " << NewG->getName() << '\n');
|
2010-09-07 09:42:10 +08:00
|
|
|
++NumThunksWritten;
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Replace G with an alias to F and delete G.
|
|
|
|
void MergeFunctions::writeAlias(Function *F, Function *G) {
|
2014-05-16 21:34:04 +08:00
|
|
|
PointerType *PTy = G->getType();
|
2014-05-18 05:29:57 +08:00
|
|
|
auto *GA = GlobalAlias::create(PTy->getElementType(), PTy->getAddressSpace(),
|
|
|
|
G->getLinkage(), "", F);
|
2011-01-25 16:56:50 +08:00
|
|
|
F->setAlignment(std::max(F->getAlignment(), G->getAlignment()));
|
|
|
|
GA->takeName(G);
|
|
|
|
GA->setVisibility(G->getVisibility());
|
2011-01-28 16:43:14 +08:00
|
|
|
removeUsers(G);
|
2011-01-25 16:56:50 +08:00
|
|
|
G->replaceAllUsesWith(GA);
|
|
|
|
G->eraseFromParent();
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
DEBUG(dbgs() << "writeAlias: " << GA->getName() << '\n');
|
2011-01-25 16:56:50 +08:00
|
|
|
++NumAliasesWritten;
|
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Merge two equivalent functions. Upon completion, Function G is deleted.
|
|
|
|
void MergeFunctions::mergeTwoFunctions(Function *F, Function *G) {
|
2010-09-07 09:42:10 +08:00
|
|
|
if (F->mayBeOverridden()) {
|
|
|
|
assert(G->mayBeOverridden());
|
2009-06-12 23:56:56 +08:00
|
|
|
|
2011-01-25 16:56:50 +08:00
|
|
|
if (HasGlobalAliases) {
|
|
|
|
// Make them both thunks to the same internal function.
|
|
|
|
Function *H = Function::Create(F->getFunctionType(), F->getLinkage(), "",
|
|
|
|
F->getParent());
|
|
|
|
H->copyAttributesFrom(F);
|
|
|
|
H->takeName(F);
|
2011-01-28 16:43:14 +08:00
|
|
|
removeUsers(F);
|
2011-01-25 16:56:50 +08:00
|
|
|
F->replaceAllUsesWith(H);
|
2009-06-12 23:56:56 +08:00
|
|
|
|
2011-01-25 16:56:50 +08:00
|
|
|
unsigned MaxAlignment = std::max(G->getAlignment(), H->getAlignment());
|
2010-08-10 05:03:28 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
writeAlias(F, G);
|
|
|
|
writeAlias(F, H);
|
2009-06-12 23:56:56 +08:00
|
|
|
|
2011-01-25 16:56:50 +08:00
|
|
|
F->setAlignment(MaxAlignment);
|
|
|
|
F->setLinkage(GlobalValue::PrivateLinkage);
|
|
|
|
} else {
|
|
|
|
// We can't merge them. Instead, pick one and update all direct callers
|
|
|
|
// to call it and hope that we improve the instruction cache hit rate.
|
|
|
|
replaceDirectCallers(G, F);
|
|
|
|
}
|
2010-09-07 09:42:10 +08:00
|
|
|
|
|
|
|
++NumDoubleWeak;
|
2010-08-06 15:21:30 +08:00
|
|
|
} else {
|
2011-01-28 16:43:14 +08:00
|
|
|
writeThunkOrAlias(F, G);
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
|
2009-06-12 16:04:51 +08:00
|
|
|
++NumFunctionsMerged;
|
2008-11-02 13:52:50 +08:00
|
|
|
}
|
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Insert a ComparableFunction into the FnSet, or merge it away if equal to one
|
|
|
|
// that was already inserted.
|
|
|
|
bool MergeFunctions::insert(ComparableFunction &NewF) {
|
2010-09-05 16:22:49 +08:00
|
|
|
std::pair<FnSetType::iterator, bool> Result = FnSet.insert(NewF);
|
2011-02-09 14:32:02 +08:00
|
|
|
if (Result.second) {
|
|
|
|
DEBUG(dbgs() << "Inserting as unique: " << NewF.getFunc()->getName() << '\n');
|
2010-09-05 16:22:49 +08:00
|
|
|
return false;
|
2011-02-09 14:32:02 +08:00
|
|
|
}
|
2010-08-31 13:53:05 +08:00
|
|
|
|
2010-09-05 17:00:32 +08:00
|
|
|
const ComparableFunction &OldF = *Result.first;
|
2010-09-05 16:22:49 +08:00
|
|
|
|
2013-10-02 02:05:30 +08:00
|
|
|
// Don't merge tiny functions, since it can just end up making the function
|
|
|
|
// larger.
|
|
|
|
// FIXME: Should still merge them if they are unnamed_addr and produce an
|
|
|
|
// alias.
|
|
|
|
if (NewF.getFunc()->size() == 1) {
|
|
|
|
if (NewF.getFunc()->front().size() <= 2) {
|
|
|
|
DEBUG(dbgs() << NewF.getFunc()->getName()
|
|
|
|
<< " is to small to bother merging\n");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2010-09-05 16:22:49 +08:00
|
|
|
// Never thunk a strong function to a weak function.
|
2010-09-07 09:42:10 +08:00
|
|
|
assert(!OldF.getFunc()->mayBeOverridden() ||
|
|
|
|
NewF.getFunc()->mayBeOverridden());
|
2010-09-05 16:22:49 +08:00
|
|
|
|
2010-09-05 17:00:32 +08:00
|
|
|
DEBUG(dbgs() << " " << OldF.getFunc()->getName() << " == "
|
|
|
|
<< NewF.getFunc()->getName() << '\n');
|
2010-09-05 16:22:49 +08:00
|
|
|
|
2010-09-05 17:00:32 +08:00
|
|
|
Function *DeleteF = NewF.getFunc();
|
|
|
|
NewF.release();
|
2011-01-28 16:43:14 +08:00
|
|
|
mergeTwoFunctions(OldF.getFunc(), DeleteF);
|
2010-09-05 16:22:49 +08:00
|
|
|
return true;
|
2010-08-08 13:04:23 +08:00
|
|
|
}
|
2009-06-12 16:04:51 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// Remove a function from FnSet. If it was already in FnSet, add it to Deferred
|
|
|
|
// so that we'll look at it in the next round.
|
|
|
|
void MergeFunctions::remove(Function *F) {
|
2011-02-09 14:32:02 +08:00
|
|
|
// We need to make sure we remove F, not a function "equal" to F per the
|
|
|
|
// function equality comparator.
|
|
|
|
//
|
|
|
|
// The special "lookup only" ComparableFunction bypasses the expensive
|
|
|
|
// function comparison in favour of a pointer comparison on the underlying
|
|
|
|
// Function*'s.
|
|
|
|
ComparableFunction CF = ComparableFunction(F, ComparableFunction::LookupOnly);
|
2011-01-02 10:46:33 +08:00
|
|
|
if (FnSet.erase(CF)) {
|
2011-02-09 14:32:02 +08:00
|
|
|
DEBUG(dbgs() << "Removed " << F->getName() << " from set and deferred it.\n");
|
2011-01-02 10:46:33 +08:00
|
|
|
Deferred.push_back(F);
|
2010-08-31 13:53:05 +08:00
|
|
|
}
|
2011-01-02 10:46:33 +08:00
|
|
|
}
|
2010-09-05 16:22:49 +08:00
|
|
|
|
2011-01-28 16:43:14 +08:00
|
|
|
// For each instruction used by the value, remove() the function that contains
|
|
|
|
// the instruction. This should happen right before a call to RAUW.
|
|
|
|
void MergeFunctions::removeUsers(Value *V) {
|
2011-01-03 03:16:44 +08:00
|
|
|
std::vector<Value *> Worklist;
|
|
|
|
Worklist.push_back(V);
|
|
|
|
while (!Worklist.empty()) {
|
|
|
|
Value *V = Worklist.back();
|
|
|
|
Worklist.pop_back();
|
|
|
|
|
2014-03-09 11:16:01 +08:00
|
|
|
for (User *U : V->users()) {
|
|
|
|
if (Instruction *I = dyn_cast<Instruction>(U)) {
|
2011-01-28 16:43:14 +08:00
|
|
|
remove(I->getParent()->getParent());
|
2014-03-09 11:16:01 +08:00
|
|
|
} else if (isa<GlobalValue>(U)) {
|
2011-01-15 18:16:23 +08:00
|
|
|
// do nothing
|
2014-03-09 11:16:01 +08:00
|
|
|
} else if (Constant *C = dyn_cast<Constant>(U)) {
|
|
|
|
for (User *UU : C->users())
|
|
|
|
Worklist.push_back(UU);
|
2011-01-03 03:16:44 +08:00
|
|
|
}
|
2010-09-05 16:22:49 +08:00
|
|
|
}
|
2010-08-31 13:53:05 +08:00
|
|
|
}
|
2010-09-05 16:22:49 +08:00
|
|
|
}
|