Enhance transform passes so that they apply the same tranforms to malloc calls as to MallocInst.
Reviewed by Dan Gohman.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82300 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index 36c90f5..9f72659 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -32,6 +32,7 @@
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Analysis/MemoryDependenceAnalysis.h"
#include "llvm/Support/CFG.h"
#include "llvm/Support/CommandLine.h"
@@ -982,7 +983,7 @@
Instruction *DepInst = DepInfo.getInst();
// Loading the allocation -> undef.
- if (isa<AllocationInst>(DepInst)) {
+ if (isa<AllocationInst>(DepInst) || isMalloc(DepInst)) {
ValuesPerBlock.push_back(std::make_pair(DepBB,
UndefValue::get(LI->getType())));
continue;
@@ -1270,7 +1271,7 @@
// If this load really doesn't depend on anything, then we must be loading an
// undef value. This can happen when loading for a fresh allocation with no
// intervening stores, for example.
- if (isa<AllocationInst>(DepInst)) {
+ if (isa<AllocationInst>(DepInst) || isMalloc(DepInst)) {
L->replaceAllUsesWith(UndefValue::get(L->getType()));
toErase.push_back(L);
NumGVNLoad++;
@@ -1393,7 +1394,7 @@
// Allocations are always uniquely numbered, so we can save time and memory
// by fast failing them.
- } else if (isa<AllocationInst>(I) || isa<TerminatorInst>(I)) {
+ } else if (isa<AllocationInst>(I) || isMalloc(I) || isa<TerminatorInst>(I)) {
localAvail[I->getParent()]->table.insert(std::make_pair(num, I));
return false;
}
@@ -1558,8 +1559,8 @@
BE = CurrentBlock->end(); BI != BE; ) {
Instruction *CurInst = BI++;
- if (isa<AllocationInst>(CurInst) || isa<TerminatorInst>(CurInst) ||
- isa<PHINode>(CurInst) ||
+ if (isa<AllocationInst>(CurInst) || isMalloc(CurInst) ||
+ isa<TerminatorInst>(CurInst) || isa<PHINode>(CurInst) ||
(CurInst->getType() == Type::getVoidTy(F.getContext())) ||
CurInst->mayReadFromMemory() || CurInst->mayHaveSideEffects() ||
isa<DbgInfoIntrinsic>(CurInst))
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index e6bd192..8d61fce 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -42,6 +42,7 @@
#include "llvm/GlobalVariable.h"
#include "llvm/Operator.h"
#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
@@ -89,6 +90,7 @@
/// Add - Add the specified instruction to the worklist if it isn't already
/// in it.
void Add(Instruction *I) {
+ DEBUG(errs() << "IC: ADD: " << *I << '\n');
if (WorklistMap.insert(std::make_pair(I, Worklist.size())).second)
Worklist.push_back(I);
}
@@ -326,7 +328,7 @@
// instruction. Instead, visit methods should return the value returned by
// this function.
Instruction *EraseInstFromFunction(Instruction &I) {
- DEBUG(errs() << "IC: erase " << I << '\n');
+ DEBUG(errs() << "IC: ERASE " << I << '\n');
assert(I.use_empty() && "Cannot erase instruction that is used!");
// Make sure that we reprocess all operands now that we reduced their
@@ -5891,9 +5893,9 @@
// icmp <global/alloca*/null>, <global/alloca*/null> - Global/Stack value
// addresses never equal each other! We already know that Op0 != Op1.
- if ((isa<GlobalValue>(Op0) || isa<AllocaInst>(Op0) ||
+ if ((isa<GlobalValue>(Op0) || isa<AllocaInst>(Op0) || isMalloc(Op0) ||
isa<ConstantPointerNull>(Op0)) &&
- (isa<GlobalValue>(Op1) || isa<AllocaInst>(Op1) ||
+ (isa<GlobalValue>(Op1) || isa<AllocaInst>(Op1) || isMalloc(Op1) ||
isa<ConstantPointerNull>(Op1)))
return ReplaceInstUsesWith(I, ConstantInt::get(Type::getInt1Ty(*Context),
!I.isTrueWhenEqual()));
@@ -6231,8 +6233,33 @@
// can assume it is successful and remove the malloc.
if (LHSI->hasOneUse() && isa<ConstantPointerNull>(RHSC)) {
Worklist.Add(LHSI);
- return ReplaceInstUsesWith(I, ConstantInt::get(Type::getInt1Ty(*Context),
- !I.isTrueWhenEqual()));
+ return ReplaceInstUsesWith(I,
+ ConstantInt::get(Type::getInt1Ty(*Context),
+ !I.isTrueWhenEqual()));
+ }
+ break;
+ case Instruction::Call:
+ // If we have (malloc != null), and if the malloc has a single use, we
+ // can assume it is successful and remove the malloc.
+ if (isMalloc(LHSI) && LHSI->hasOneUse() &&
+ isa<ConstantPointerNull>(RHSC)) {
+ Worklist.Add(LHSI);
+ return ReplaceInstUsesWith(I,
+ ConstantInt::get(Type::getInt1Ty(*Context),
+ !I.isTrueWhenEqual()));
+ }
+ break;
+ case Instruction::BitCast:
+ // If we have (malloc != null), and if the malloc has a single use, we
+ // can assume it is successful and remove the malloc.
+ CallInst* CI = extractMallocCallFromBitCast(LHSI);
+ if (CI && CI->hasOneUse() && LHSI->hasOneUse()
+ && isa<ConstantPointerNull>(RHSC)) {
+ Worklist.Add(LHSI);
+ Worklist.Add(CI);
+ return ReplaceInstUsesWith(I,
+ ConstantInt::get(Type::getInt1Ty(*Context),
+ !I.isTrueWhenEqual()));
}
break;
}
@@ -8784,8 +8811,10 @@
if (SrcPTy->getAddressSpace() != DstPTy->getAddressSpace())
return 0;
- // If we are casting a malloc or alloca to a pointer to a type of the same
+ // If we are casting a alloca to a pointer to a type of the same
// size, rewrite the allocation instruction to allocate the "right" type.
+ // There is no need to modify malloc calls because it is their bitcast that
+ // needs to be cleaned up.
if (AllocationInst *AI = dyn_cast<AllocationInst>(Src))
if (Instruction *V = PromoteCastOfAllocation(CI, *AI))
return V;
@@ -9459,6 +9488,7 @@
Align = PrefAlign;
}
}
+ // No alignment changes are possible for malloc calls
}
return Align;
@@ -9796,7 +9826,7 @@
TerminatorInst *TI = II->getParent()->getTerminator();
bool CannotRemove = false;
for (++BI; &*BI != TI; ++BI) {
- if (isa<AllocaInst>(BI)) {
+ if (isa<AllocaInst>(BI) || isMalloc(BI)) {
CannotRemove = true;
break;
}
@@ -11060,7 +11090,8 @@
if (Offset == 0) {
// If the bitcast is of an allocation, and the allocation will be
// converted to match the type of the cast, don't touch this.
- if (isa<AllocationInst>(BCI->getOperand(0))) {
+ if (isa<AllocationInst>(BCI->getOperand(0)) ||
+ isMalloc(BCI->getOperand(0))) {
// See if the bitcast simplifies, if so, don't nuke this GEP yet.
if (Instruction *I = visitBitCast(*BCI)) {
if (I != BCI) {
@@ -11191,6 +11222,21 @@
EraseInstFromFunction(FI);
return EraseInstFromFunction(*MI);
}
+ if (isMalloc(Op)) {
+ if (CallInst* CI = extractMallocCallFromBitCast(Op)) {
+ if (Op->hasOneUse() && CI->hasOneUse()) {
+ EraseInstFromFunction(FI);
+ EraseInstFromFunction(*CI);
+ return EraseInstFromFunction(*cast<Instruction>(Op));
+ }
+ } else {
+ // Op is a call to malloc
+ if (Op->hasOneUse()) {
+ EraseInstFromFunction(FI);
+ return EraseInstFromFunction(*cast<Instruction>(Op));
+ }
+ }
+ }
return 0;
}
diff --git a/lib/Transforms/Scalar/Reassociate.cpp b/lib/Transforms/Scalar/Reassociate.cpp
index e6ffac2..9160654 100644
--- a/lib/Transforms/Scalar/Reassociate.cpp
+++ b/lib/Transforms/Scalar/Reassociate.cpp
@@ -29,6 +29,7 @@
#include "llvm/IntrinsicInst.h"
#include "llvm/LLVMContext.h"
#include "llvm/Pass.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/Support/CFG.h"
#include "llvm/Support/Debug.h"
@@ -121,7 +122,7 @@
if (I->getOpcode() == Instruction::PHI ||
I->getOpcode() == Instruction::Alloca ||
I->getOpcode() == Instruction::Load ||
- I->getOpcode() == Instruction::Malloc ||
+ I->getOpcode() == Instruction::Malloc || isMalloc(I) ||
I->getOpcode() == Instruction::Invoke ||
(I->getOpcode() == Instruction::Call &&
!isa<DbgInfoIntrinsic>(I)) ||
diff --git a/lib/Transforms/Scalar/SCCP.cpp b/lib/Transforms/Scalar/SCCP.cpp
index e1f0ba5..f0b5d77 100644
--- a/lib/Transforms/Scalar/SCCP.cpp
+++ b/lib/Transforms/Scalar/SCCP.cpp
@@ -30,6 +30,7 @@
#include "llvm/LLVMContext.h"
#include "llvm/Pass.h"
#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Support/CallSite.h"
@@ -400,7 +401,12 @@
void visitStoreInst (Instruction &I);
void visitLoadInst (LoadInst &I);
void visitGetElementPtrInst(GetElementPtrInst &I);
- void visitCallInst (CallInst &I) { visitCallSite(CallSite::get(&I)); }
+ void visitCallInst (CallInst &I) {
+ if (isMalloc(&I))
+ markOverdefined(&I);
+ else
+ visitCallSite(CallSite::get(&I));
+ }
void visitInvokeInst (InvokeInst &II) {
visitCallSite(CallSite::get(&II));
visitTerminatorInst(II);
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index 419d66f..96ea0e4 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -1853,7 +1853,13 @@
}
break;
case 'm':
- if (Name == "memcmp") {
+ if (Name == "malloc") {
+ if (FTy->getNumParams() != 1 ||
+ !isa<PointerType>(FTy->getReturnType()))
+ continue;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ } else if (Name == "memcmp") {
if (FTy->getNumParams() != 3 ||
!isa<PointerType>(FTy->getParamType(0)) ||
!isa<PointerType>(FTy->getParamType(1)))
diff --git a/lib/Transforms/Scalar/TailDuplication.cpp b/lib/Transforms/Scalar/TailDuplication.cpp
index 4bad708..8345175 100644
--- a/lib/Transforms/Scalar/TailDuplication.cpp
+++ b/lib/Transforms/Scalar/TailDuplication.cpp
@@ -28,6 +28,7 @@
#include "llvm/Type.h"
#include "llvm/Support/CFG.h"
#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
@@ -129,7 +130,7 @@
if (isa<CallInst>(I) || isa<InvokeInst>(I)) return false;
// Allso alloca and malloc.
- if (isa<AllocationInst>(I)) return false;
+ if (isa<AllocationInst>(I) || isMalloc(I)) return false;
// Some vector instructions can expand into a number of instructions.
if (isa<ShuffleVectorInst>(I) || isa<ExtractElementInst>(I) ||