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authorDerek Schuff <dschuff@chromium.org>2013-01-30 11:34:40 -0800
committerDerek Schuff <dschuff@chromium.org>2013-01-30 11:34:40 -0800
commit1843e19bce9b11fc840858e136c6c52cf8b42e0b (patch)
treee8bfc928152e2d3b3dd120d141d13dc08a9b49e4 /lib/Analysis/MemoryBuiltins.cpp
parentaa0fa8a8df25807f784ec9ca9deeb40328636595 (diff)
parenta662a9862501fc86904e90054f7c1519101d9126 (diff)
Merge commit 'a662a9862501fc86904e90054f7c1519101d9126'
Conflicts: include/llvm/CodeGen/IntrinsicLowering.h include/llvm/MC/MCAssembler.h include/llvm/MC/MCObjectStreamer.h lib/LLVMBuild.txt lib/Linker/LinkArchives.cpp lib/MC/MCAssembler.cpp lib/MC/MCELFStreamer.cpp lib/MC/MCParser/AsmParser.cpp lib/MC/MCPureStreamer.cpp lib/MC/WinCOFFStreamer.cpp lib/Makefile lib/Support/Unix/Memory.inc lib/Support/Unix/Process.inc lib/Support/Unix/Program.inc lib/Target/ARM/ARM.h lib/Target/ARM/ARMFastISel.cpp lib/Target/ARM/ARMISelLowering.cpp lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp lib/Target/Mips/MipsInstrFPU.td lib/Target/X86/CMakeLists.txt lib/Target/X86/X86ISelLowering.cpp lib/Target/X86/X86TargetMachine.cpp lib/Target/X86/X86TargetObjectFile.cpp lib/Transforms/InstCombine/InstCombineCalls.cpp test/CodeGen/X86/fast-isel-x86-64.ll tools/llc/llc.cpp tools/lto/LTOModule.cpp utils/TableGen/EDEmitter.cpp
Diffstat (limited to 'lib/Analysis/MemoryBuiltins.cpp')
-rw-r--r--lib/Analysis/MemoryBuiltins.cpp69
1 files changed, 47 insertions, 22 deletions
diff --git a/lib/Analysis/MemoryBuiltins.cpp b/lib/Analysis/MemoryBuiltins.cpp
index 0c6568a093..1d27a83d93 100644
--- a/lib/Analysis/MemoryBuiltins.cpp
+++ b/lib/Analysis/MemoryBuiltins.cpp
@@ -17,12 +17,12 @@
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/DataLayout.h"
-#include "llvm/GlobalVariable.h"
-#include "llvm/Instructions.h"
-#include "llvm/Intrinsics.h"
-#include "llvm/Metadata.h"
-#include "llvm/Module.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/Metadata.h"
+#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
@@ -132,7 +132,7 @@ static const AllocFnsTy *getAllocationData(const Value *V, AllocType AllocTy,
static bool hasNoAliasAttr(const Value *V, bool LookThroughBitCast) {
ImmutableCallSite CS(LookThroughBitCast ? V->stripPointerCasts() : V);
- return CS && CS.hasFnAttr(Attributes::NoAlias);
+ return CS && CS.hasFnAttr(Attribute::NoAlias);
}
@@ -385,20 +385,29 @@ ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const DataLayout *TD,
SizeOffsetType ObjectSizeOffsetVisitor::compute(Value *V) {
V = V->stripPointerCasts();
- if (Instruction *I = dyn_cast<Instruction>(V)) {
- // If we have already seen this instruction, bail out. Cycles can happen in
- // unreachable code after constant propagation.
- if (!SeenInsts.insert(I))
- return unknown();
+ if (isa<Instruction>(V) || isa<GEPOperator>(V)) {
+ // return cached value or insert unknown in cache if size of V was not
+ // computed yet in order to avoid recursions in PHis
+ std::pair<CacheMapTy::iterator, bool> CacheVal =
+ CacheMap.insert(std::make_pair(V, unknown()));
+ if (!CacheVal.second)
+ return CacheVal.first->second;
+
+ SizeOffsetType Result;
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V))
- return visitGEPOperator(*GEP);
- return visit(*I);
+ Result = visitGEPOperator(*GEP);
+ else
+ Result = visit(cast<Instruction>(*V));
+ return CacheMap[V] = Result;
}
+
if (Argument *A = dyn_cast<Argument>(V))
return visitArgument(*A);
if (ConstantPointerNull *P = dyn_cast<ConstantPointerNull>(V))
return visitConstantPointerNull(*P);
+ if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V))
+ return visitGlobalAlias(*GA);
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
return visitGlobalVariable(*GV);
if (UndefValue *UV = dyn_cast<UndefValue>(V))
@@ -406,8 +415,6 @@ SizeOffsetType ObjectSizeOffsetVisitor::compute(Value *V) {
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
if (CE->getOpcode() == Instruction::IntToPtr)
return unknown(); // clueless
- if (CE->getOpcode() == Instruction::GetElementPtr)
- return visitGEPOperator(cast<GEPOperator>(*CE));
}
DEBUG(dbgs() << "ObjectSizeOffsetVisitor::compute() unhandled value: " << *V
@@ -510,14 +517,19 @@ ObjectSizeOffsetVisitor::visitExtractValueInst(ExtractValueInst&) {
SizeOffsetType ObjectSizeOffsetVisitor::visitGEPOperator(GEPOperator &GEP) {
SizeOffsetType PtrData = compute(GEP.getPointerOperand());
- if (!bothKnown(PtrData) || !GEP.hasAllConstantIndices())
+ APInt Offset(IntTyBits, 0);
+ if (!bothKnown(PtrData) || !GEP.accumulateConstantOffset(*TD, Offset))
return unknown();
- SmallVector<Value*, 8> Ops(GEP.idx_begin(), GEP.idx_end());
- APInt Offset(IntTyBits,TD->getIndexedOffset(GEP.getPointerOperandType(),Ops));
return std::make_pair(PtrData.first, PtrData.second + Offset);
}
+SizeOffsetType ObjectSizeOffsetVisitor::visitGlobalAlias(GlobalAlias &GA) {
+ if (GA.mayBeOverridden())
+ return unknown();
+ return compute(GA.getAliasee());
+}
+
SizeOffsetType ObjectSizeOffsetVisitor::visitGlobalVariable(GlobalVariable &GV){
if (!GV.hasDefinitiveInitializer())
return unknown();
@@ -536,9 +548,21 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitLoadInst(LoadInst&) {
return unknown();
}
-SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode&) {
- // too complex to analyze statically.
- return unknown();
+SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode &PHI) {
+ if (PHI.getNumIncomingValues() == 0)
+ return unknown();
+
+ SizeOffsetType Ret = compute(PHI.getIncomingValue(0));
+ if (!bothKnown(Ret))
+ return unknown();
+
+ // verify that all PHI incoming pointers have the same size and offset
+ for (unsigned i = 1, e = PHI.getNumIncomingValues(); i != e; ++i) {
+ SizeOffsetType EdgeData = compute(PHI.getIncomingValue(i));
+ if (!bothKnown(EdgeData) || EdgeData != Ret)
+ return unknown();
+ }
+ return Ret;
}
SizeOffsetType ObjectSizeOffsetVisitor::visitSelectInst(SelectInst &I) {
@@ -619,6 +643,7 @@ SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute_(Value *V) {
} else if (isa<Argument>(V) ||
(isa<ConstantExpr>(V) &&
cast<ConstantExpr>(V)->getOpcode() == Instruction::IntToPtr) ||
+ isa<GlobalAlias>(V) ||
isa<GlobalVariable>(V)) {
// ignore values where we cannot do more than what ObjectSizeVisitor can
Result = unknown();