97 lines
3.7 KiB
C++
97 lines
3.7 KiB
C++
//===- CodeMetrics.cpp - Code cost measurements ---------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file implements code cost measurement utilities.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Analysis/CodeMetrics.h"
|
|
#include "llvm/Analysis/TargetTransformInfo.h"
|
|
#include "llvm/IR/DataLayout.h"
|
|
#include "llvm/IR/Function.h"
|
|
#include "llvm/IR/IntrinsicInst.h"
|
|
#include "llvm/Support/CallSite.h"
|
|
|
|
using namespace llvm;
|
|
|
|
/// analyzeBasicBlock - Fill in the current structure with information gleaned
|
|
/// from the specified block.
|
|
void CodeMetrics::analyzeBasicBlock(const BasicBlock *BB,
|
|
const TargetTransformInfo &TTI) {
|
|
++NumBlocks;
|
|
unsigned NumInstsBeforeThisBB = NumInsts;
|
|
for (BasicBlock::const_iterator II = BB->begin(), E = BB->end();
|
|
II != E; ++II) {
|
|
// Special handling for calls.
|
|
if (isa<CallInst>(II) || isa<InvokeInst>(II)) {
|
|
ImmutableCallSite CS(cast<Instruction>(II));
|
|
|
|
if (const Function *F = CS.getCalledFunction()) {
|
|
// If a function is both internal and has a single use, then it is
|
|
// extremely likely to get inlined in the future (it was probably
|
|
// exposed by an interleaved devirtualization pass).
|
|
if (!CS.isNoInline() && F->hasInternalLinkage() && F->hasOneUse())
|
|
++NumInlineCandidates;
|
|
|
|
// If this call is to function itself, then the function is recursive.
|
|
// Inlining it into other functions is a bad idea, because this is
|
|
// basically just a form of loop peeling, and our metrics aren't useful
|
|
// for that case.
|
|
if (F == BB->getParent())
|
|
isRecursive = true;
|
|
|
|
if (TTI.isLoweredToCall(F))
|
|
++NumCalls;
|
|
} else {
|
|
// We don't want inline asm to count as a call - that would prevent loop
|
|
// unrolling. The argument setup cost is still real, though.
|
|
if (!isa<InlineAsm>(CS.getCalledValue()))
|
|
++NumCalls;
|
|
}
|
|
}
|
|
|
|
if (const AllocaInst *AI = dyn_cast<AllocaInst>(II)) {
|
|
if (!AI->isStaticAlloca())
|
|
this->usesDynamicAlloca = true;
|
|
}
|
|
|
|
if (isa<ExtractElementInst>(II) || II->getType()->isVectorTy())
|
|
++NumVectorInsts;
|
|
|
|
if (const CallInst *CI = dyn_cast<CallInst>(II))
|
|
if (CI->hasFnAttr(Attribute::NoDuplicate))
|
|
notDuplicatable = true;
|
|
|
|
if (const InvokeInst *InvI = dyn_cast<InvokeInst>(II))
|
|
if (InvI->hasFnAttr(Attribute::NoDuplicate))
|
|
notDuplicatable = true;
|
|
|
|
NumInsts += TTI.getUserCost(&*II);
|
|
}
|
|
|
|
if (isa<ReturnInst>(BB->getTerminator()))
|
|
++NumRets;
|
|
|
|
// We never want to inline functions that contain an indirectbr. This is
|
|
// incorrect because all the blockaddress's (in static global initializers
|
|
// for example) would be referring to the original function, and this indirect
|
|
// jump would jump from the inlined copy of the function into the original
|
|
// function which is extremely undefined behavior.
|
|
// FIXME: This logic isn't really right; we can safely inline functions
|
|
// with indirectbr's as long as no other function or global references the
|
|
// blockaddress of a block within the current function. And as a QOI issue,
|
|
// if someone is using a blockaddress without an indirectbr, and that
|
|
// reference somehow ends up in another function or global, we probably
|
|
// don't want to inline this function.
|
|
notDuplicatable |= isa<IndirectBrInst>(BB->getTerminator());
|
|
|
|
// Remember NumInsts for this BB.
|
|
NumBBInsts[BB] = NumInsts - NumInstsBeforeThisBB;
|
|
}
|