diff --git a/include/llvm/Operator.h b/include/llvm/Operator.h index 2f9f9ca12ce..a26d9400796 100644 --- a/include/llvm/Operator.h +++ b/include/llvm/Operator.h @@ -171,24 +171,6 @@ public: return true; } - /// hasNoPointerOverflow - Return true if this GetElementPtr is known to - /// never have overflow in the pointer addition portions of its effective - /// computation. GetElementPtr computation involves several phases; - /// overflow can be considered to occur in index typecasting, array index - /// scaling, and the addition of the base pointer with offsets. This flag - /// only applies to the last of these. The operands are added to the base - /// pointer one at a time from left to right. This function returns false - /// if any of these additions results in an address value which is not - /// known to be within the allocated address space that the base pointer - /// points into, or within one element (of the original allocation) past - /// the end. - bool hasNoPointerOverflow() const { - return SubclassOptionalData & (1 << 0); - } - void setHasNoPointerOverflow(bool B) { - SubclassOptionalData = (SubclassOptionalData & ~(1 << 0)) | (B << 0); - } - // Methods for support type inquiry through isa, cast, and dyn_cast: static inline bool classof(const GEPOperator *) { return true; } static inline bool classof(const GetElementPtrInst *) { return true; } diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp index dcb5903a14e..308c69a87ee 100644 --- a/lib/Analysis/BasicAliasAnalysis.cpp +++ b/lib/Analysis/BasicAliasAnalysis.cpp @@ -38,13 +38,8 @@ using namespace llvm; // Useful predicates //===----------------------------------------------------------------------===// -static const User *isGEP(const Value *V) { - if (const GEPOperator *GEP = dyn_cast(V)) - // For the purposes of BasicAliasAnalysis, if the GEP has overflow it - // could do crazy things. - if (GEP->hasNoPointerOverflow()) - return GEP; - return 0; +static const GEPOperator *isGEP(const Value *V) { + return dyn_cast(V); } static const Value *GetGEPOperands(const Value *V, diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp index 6c23f401c5b..aadba9d9d3d 100644 --- a/lib/Analysis/ScalarEvolution.cpp +++ b/lib/Analysis/ScalarEvolution.cpp @@ -2938,15 +2938,10 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) { return getSCEV(U->getOperand(0)); break; - case Instruction::IntToPtr: - if (!TD) break; // Without TD we can't analyze pointers. - return getTruncateOrZeroExtend(getSCEV(U->getOperand(0)), - TD->getIntPtrType()); - - case Instruction::PtrToInt: - if (!TD) break; // Without TD we can't analyze pointers. - return getTruncateOrZeroExtend(getSCEV(U->getOperand(0)), - U->getType()); + // It's tempting to handle inttoptr and ptrtoint, however this can + // lead to pointer expressions which cannot be expanded to GEPs + // (because they may overflow). For now, the only pointer-typed + // expressions we handle are GEPs and address literals. case Instruction::GetElementPtr: if (!TD) break; // Without TD we can't analyze pointers. diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 94547b48bb5..d2ed1e14e3f 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -2276,31 +2276,6 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) { return R; } - // add (cast *A to intptrtype) B -> - // cast (GEP (cast *A to i8*) B) --> intptrtype - { - CastInst *CI = dyn_cast(LHS); - Value *Other = RHS; - if (!CI) { - CI = dyn_cast(RHS); - Other = LHS; - } - if (CI && CI->getType()->isSized() && - (CI->getType()->getScalarSizeInBits() == - TD->getIntPtrType()->getPrimitiveSizeInBits()) - && isa(CI->getOperand(0)->getType())) { - unsigned AS = - cast(CI->getOperand(0)->getType())->getAddressSpace(); - Value *I2 = InsertBitCastBefore(CI->getOperand(0), - Context->getPointerType(Type::Int8Ty, AS), I); - GetElementPtrInst *GEP = GetElementPtrInst::Create(I2, Other, "ctg2"); - // A GEP formed from an arbitrary add may overflow. - cast(GEP)->setHasNoPointerOverflow(false); - I2 = InsertNewInstBefore(GEP, I); - return new PtrToIntInst(I2, CI->getType()); - } - } - // add (select X 0 (sub n A)) A --> select X A n { SelectInst *SI = dyn_cast(LHS); @@ -8914,65 +8889,7 @@ Instruction *InstCombiner::visitIntToPtr(IntToPtrInst &CI) { if (Instruction *I = commonCastTransforms(CI)) return I; - - const Type *DestPointee = cast(CI.getType())->getElementType(); - if (!DestPointee->isSized()) return 0; - // If this is inttoptr(add (ptrtoint x), cst), try to turn this into a GEP. - ConstantInt *Cst; - Value *X; - if (match(CI.getOperand(0), m_Add(m_Cast(m_Value(X)), - m_ConstantInt(Cst)), *Context)) { - // If the source and destination operands have the same type, see if this - // is a single-index GEP. - if (X->getType() == CI.getType()) { - // Get the size of the pointee type. - uint64_t Size = TD->getTypeAllocSize(DestPointee); - - // Convert the constant to intptr type. - APInt Offset = Cst->getValue(); - Offset.sextOrTrunc(TD->getPointerSizeInBits()); - - // If Offset is evenly divisible by Size, we can do this xform. - if (Size && !APIntOps::srem(Offset, APInt(Offset.getBitWidth(), Size))){ - Offset = APIntOps::sdiv(Offset, APInt(Offset.getBitWidth(), Size)); - GetElementPtrInst *GEP = - GetElementPtrInst::Create(X, Context->getConstantInt(Offset)); - // A gep synthesized from inttoptr+add+ptrtoint must be assumed to - // potentially overflow, in the absense of further analysis. - cast(GEP)->setHasNoPointerOverflow(false); - return GEP; - } - } - // TODO: Could handle other cases, e.g. where add is indexing into field of - // struct etc. - } else if (CI.getOperand(0)->hasOneUse() && - match(CI.getOperand(0), m_Add(m_Value(X), - m_ConstantInt(Cst)), *Context)) { - // Otherwise, if this is inttoptr(add x, cst), try to turn this into an - // "inttoptr+GEP" instead of "add+intptr". - - // Get the size of the pointee type. - uint64_t Size = TD->getTypeAllocSize(DestPointee); - - // Convert the constant to intptr type. - APInt Offset = Cst->getValue(); - Offset.sextOrTrunc(TD->getPointerSizeInBits()); - - // If Offset is evenly divisible by Size, we can do this xform. - if (Size && !APIntOps::srem(Offset, APInt(Offset.getBitWidth(), Size))){ - Offset = APIntOps::sdiv(Offset, APInt(Offset.getBitWidth(), Size)); - - Instruction *P = InsertNewInstBefore(new IntToPtrInst(X, CI.getType(), - "tmp"), CI); - GetElementPtrInst *GEP = - GetElementPtrInst::Create(P, Context->getConstantInt(Offset), "tmp"); - // A gep synthesized from inttoptr+add+ptrtoint must be assumed to - // potentially overflow, in the absense of further analysis. - cast(GEP)->setHasNoPointerOverflow(false); - return GEP; - } - } return 0; } diff --git a/lib/VMCore/Constants.cpp b/lib/VMCore/Constants.cpp index f6d8e86850f..71e98377738 100644 --- a/lib/VMCore/Constants.cpp +++ b/lib/VMCore/Constants.cpp @@ -475,11 +475,8 @@ public: static GetElementPtrConstantExpr *Create(Constant *C, const std::vector&IdxList, const Type *DestTy) { - GetElementPtrConstantExpr *Result = new(IdxList.size() + 1) - GetElementPtrConstantExpr(C, IdxList, DestTy); - // Getelementptr defaults to having no pointer overflow. - cast(Result)->setHasNoPointerOverflow(true); - return Result; + return + new(IdxList.size() + 1) GetElementPtrConstantExpr(C, IdxList, DestTy); } /// Transparently provide more efficient getOperand methods. DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value); diff --git a/lib/VMCore/Instructions.cpp b/lib/VMCore/Instructions.cpp index c1b57a6e1e4..e04d54cee37 100644 --- a/lib/VMCore/Instructions.cpp +++ b/lib/VMCore/Instructions.cpp @@ -1023,9 +1023,6 @@ void GetElementPtrInst::init(Value *Ptr, Value* const *Idx, unsigned NumIdx, OL[i+1] = Idx[i]; setName(Name); - - // GetElementPtr instructions have undefined results on overflow by default. - cast(this)->setHasNoPointerOverflow(true); } void GetElementPtrInst::init(Value *Ptr, Value *Idx, const std::string &Name) { @@ -1035,9 +1032,6 @@ void GetElementPtrInst::init(Value *Ptr, Value *Idx, const std::string &Name) { OL[1] = Idx; setName(Name); - - // GetElementPtr instructions have undefined results on overflow by default. - cast(this)->setHasNoPointerOverflow(true); } GetElementPtrInst::GetElementPtrInst(const GetElementPtrInst &GEPI) @@ -1049,10 +1043,6 @@ GetElementPtrInst::GetElementPtrInst(const GetElementPtrInst &GEPI) Use *GEPIOL = GEPI.OperandList; for (unsigned i = 0, E = NumOperands; i != E; ++i) OL[i] = GEPIOL[i]; - - // Transfer the hasNoPointerOverflow() value from the original GEPI. - cast(this) - ->setHasNoPointerOverflow(cast(GEPI).hasNoPointerOverflow()); } GetElementPtrInst::GetElementPtrInst(Value *Ptr, Value *Idx, diff --git a/lib/VMCore/Value.cpp b/lib/VMCore/Value.cpp index 279eabb0ec4..ab2e35c1af7 100644 --- a/lib/VMCore/Value.cpp +++ b/lib/VMCore/Value.cpp @@ -363,8 +363,6 @@ Value *Value::getUnderlyingObject() { unsigned MaxLookup = 6; do { if (GEPOperator *GEP = dyn_cast(V)) { - if (!GEP->hasNoPointerOverflow()) - return V; V = GEP->getPointerOperand(); } else if (Operator::getOpcode(V) == Instruction::BitCast) { V = cast(V)->getOperand(0); diff --git a/test/CodeGen/X86/iv-users-in-other-loops.ll b/test/CodeGen/X86/iv-users-in-other-loops.ll index a48f0616291..af1434ad1ae 100644 --- a/test/CodeGen/X86/iv-users-in-other-loops.ll +++ b/test/CodeGen/X86/iv-users-in-other-loops.ll @@ -3,8 +3,8 @@ ; RUN: grep dec %t | count 2 ; RUN: grep addq %t | count 13 ; RUN: not grep addb %t -; RUN: grep leaq %t | count 8 -; RUN: grep leal %t | count 4 +; RUN: grep leaq %t | count 9 +; RUN: grep leal %t | count 3 ; RUN: grep movq %t | count 5 ; IV users in each of the loops from other loops shouldn't cause LSR diff --git a/test/Transforms/IndVarSimplify/max-pointer.ll b/test/Transforms/IndVarSimplify/max-pointer.ll index ba2b2fa8348..2ee08dbc38b 100644 --- a/test/Transforms/IndVarSimplify/max-pointer.ll +++ b/test/Transforms/IndVarSimplify/max-pointer.ll @@ -22,58 +22,6 @@ return: ; preds = %bb2 ret void } -define void @bar(i8* %str1Ptr, i64 %s, i8* %inLastBytePtr) nounwind { -entry: - %str2Ptr = inttoptr i64 %s to i8* - %0 = icmp ult i8* %str2Ptr, %str1Ptr ; [#uses=1] - %str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr ; [#uses=1] - br label %bb2 - -bb2: ; preds = %bb2, %entry - %str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ] ; [#uses=1] - %1 = getelementptr i8* %str2Ptr_addr.1, i64 1 ; [#uses=2] - %2 = icmp ult i8* %1, %inLastBytePtr ; [#uses=0] - br i1 false, label %bb2, label %return - -return: ; preds = %bb2 - ret void -} - -define void @qux(i64 %t, i64 %s, i8* %inLastBytePtr) nounwind { -entry: - %str1Ptr = inttoptr i64 %t to i8* - %str2Ptr = inttoptr i64 %s to i8* - %0 = icmp ult i8* %str2Ptr, %str1Ptr ; [#uses=1] - %str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr ; [#uses=1] - br label %bb2 - -bb2: ; preds = %bb2, %entry - %str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ] ; [#uses=1] - %1 = getelementptr i8* %str2Ptr_addr.1, i64 1 ; [#uses=2] - %2 = icmp ult i8* %1, %inLastBytePtr ; [#uses=0] - br i1 false, label %bb2, label %return - -return: ; preds = %bb2 - ret void -} - -define void @vor(i64 %t, i8* %str2Ptr, i8* %inLastBytePtr) nounwind { -entry: - %str1Ptr = inttoptr i64 %t to i8* - %0 = icmp ult i8* %str2Ptr, %str1Ptr ; [#uses=1] - %str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr ; [#uses=1] - br label %bb2 - -bb2: ; preds = %bb2, %entry - %str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ] ; [#uses=1] - %1 = getelementptr i8* %str2Ptr_addr.1, i64 1 ; [#uses=2] - %2 = icmp ult i8* %1, %inLastBytePtr ; [#uses=0] - br i1 false, label %bb2, label %return - -return: ; preds = %bb2 - ret void -} - define void @sfoo(i8* %str1Ptr, i8* %str2Ptr, i8* %inLastBytePtr) nounwind { entry: %0 = icmp slt i8* %str2Ptr, %str1Ptr ; [#uses=1] @@ -89,57 +37,3 @@ bb2: ; preds = %bb2, %entry return: ; preds = %bb2 ret void } - -define void @sbar(i8* %str1Ptr, i64 %s, i8* %inLastBytePtr) nounwind { -entry: - %str2Ptr = inttoptr i64 %s to i8* - %0 = icmp slt i8* %str2Ptr, %str1Ptr ; [#uses=1] - %str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr ; [#uses=1] - br label %bb2 - -bb2: ; preds = %bb2, %entry - %str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ] ; [#uses=1] - %1 = getelementptr i8* %str2Ptr_addr.1, i64 1 ; [#uses=2] - %2 = icmp slt i8* %1, %inLastBytePtr ; [#uses=0] - br i1 false, label %bb2, label %return - -return: ; preds = %bb2 - ret void -} - -define void @squx(i64 %t, i64 %s, i8* %inLastBytePtr) nounwind { -entry: - %str1Ptr = inttoptr i64 %t to i8* - %str2Ptr = inttoptr i64 %s to i8* - %0 = icmp slt i8* %str2Ptr, %str1Ptr ; [#uses=1] - %str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr ; [#uses=1] - br label %bb2 - -bb2: ; preds = %bb2, %entry - %str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ] ; [#uses=1] - %1 = getelementptr i8* %str2Ptr_addr.1, i64 1 ; [#uses=2] - %2 = icmp slt i8* %1, %inLastBytePtr ; [#uses=0] - br i1 false, label %bb2, label %return - -return: ; preds = %bb2 - ret void -} - -define void @svor(i64 %t, i8* %str2Ptr, i8* %inLastBytePtr) nounwind { -entry: - %str1Ptr = inttoptr i64 %t to i8* - %0 = icmp slt i8* %str2Ptr, %str1Ptr ; [#uses=1] - %str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr ; [#uses=1] - br label %bb2 - -bb2: ; preds = %bb2, %entry - %str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ] ; [#uses=1] - %1 = getelementptr i8* %str2Ptr_addr.1, i64 1 ; [#uses=2] - %2 = icmp slt i8* %1, %inLastBytePtr ; [#uses=0] - br i1 false, label %bb2, label %return - -return: ; preds = %bb2 - ret void -} - - diff --git a/test/Transforms/InstCombine/add2.ll b/test/Transforms/InstCombine/add2.ll index 161d56b40b5..cd67d96a01a 100644 --- a/test/Transforms/InstCombine/add2.ll +++ b/test/Transforms/InstCombine/add2.ll @@ -1,9 +1,4 @@ -; RUN: llvm-as < %s | opt -instcombine | llvm-dis | \ -; RUN: grep -v OK | not grep add - -;; Target triple for gep raising case below. -target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128" -target triple = "i686-apple-darwin8" +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep add define i64 @test1(i64 %A, i32 %B) { %tmp12 = zext i32 %B to i64 @@ -13,23 +8,6 @@ define i64 @test1(i64 %A, i32 %B) { ret i64 %tmp6 } -; PR1795 -define void @test2(i32 %.val24) { -EntryBlock: - add i32 %.val24, -12 - inttoptr i32 %0 to i32* - store i32 1, i32* %1 - add i32 %.val24, -16 - inttoptr i32 %2 to i32* - getelementptr i32* %3, i32 1 - load i32* %4 - tail call i32 @callee( i32 %5 ) - ret void -} - -declare i32 @callee(i32) - - define i32 @test3(i32 %A) { %B = and i32 %A, 7 %C = and i32 %A, 32 diff --git a/test/Transforms/InstCombine/add3.ll b/test/Transforms/InstCombine/add3.ll new file mode 100644 index 00000000000..55e7ec7a1db --- /dev/null +++ b/test/Transforms/InstCombine/add3.ll @@ -0,0 +1,21 @@ +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep inttoptr | count 2 + +;; Target triple for gep raising case below. +target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128" +target triple = "i686-apple-darwin8" + +; PR1795 +define void @test2(i32 %.val24) { +EntryBlock: + add i32 %.val24, -12 + inttoptr i32 %0 to i32* + store i32 1, i32* %1 + add i32 %.val24, -16 + inttoptr i32 %2 to i32* + getelementptr i32* %3, i32 1 + load i32* %4 + tail call i32 @callee( i32 %5 ) + ret void +} + +declare i32 @callee(i32) diff --git a/test/Transforms/InstCombine/cast_ptr.ll b/test/Transforms/InstCombine/cast_ptr.ll index fd600a88304..9b87ed094ea 100644 --- a/test/Transforms/InstCombine/cast_ptr.ll +++ b/test/Transforms/InstCombine/cast_ptr.ll @@ -1,8 +1,15 @@ ; Tests to make sure elimination of casts is working correctly -; RUN: llvm-as < %s | opt -instcombine | llvm-dis | notcast +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | FileCheck %s target datalayout = "p:32:32" +; This shouldn't convert to getelementptr because the relationship +; between the arithmetic and the layout of allocated memory is +; entirely unknown. +; CHECK: @test1 +; CHECK: ptrtoint +; CHECK: add +; CHECK: inttoptr define i8* @test1(i8* %t) { %tmpc = ptrtoint i8* %t to i32 ; [#uses=1] %tmpa = add i32 %tmpc, 32 ; [#uses=1] @@ -10,6 +17,9 @@ define i8* @test1(i8* %t) { ret i8* %tv } +; These casts should be folded away. +; CHECK: @test2 +; CHECK: icmp eq i8* %a, %b define i1 @test2(i8* %a, i8* %b) { %tmpa = ptrtoint i8* %a to i32 ; [#uses=1] %tmpb = ptrtoint i8* %b to i32 ; [#uses=1]