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move two functions up higher in the file. Delete a useless argument

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to EmitGEPOffset.  

Implement some new transforms for optimizing 
subtracts of two pointer to ints into the same vector.  This happens
for C++ iterator idioms for example, stringmap takes a const char*
that points to the start and end of a string.  Once inlined, we want
the pointer difference to turn back into a length.

This is rdar://7362831.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86021 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2009-11-04 08:05:20 +00:00
parent 6a4ab1e426
commit 092543ca71
2 changed files with 270 additions and 177 deletions
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404
lib/Transforms/Scalar/InstructionCombining.cpp
View File

@ -217,6 +217,7 @@ namespace {
//
Instruction *visitAdd(BinaryOperator &I);
Instruction *visitFAdd(BinaryOperator &I);
Value *OptimizePointerDifference(Value *LHS, Value *RHS, const Type *Ty);
Instruction *visitSub(BinaryOperator &I);
Instruction *visitFSub(BinaryOperator &I);
Instruction *visitMul(BinaryOperator &I);
@ -2519,13 +2520,210 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
return Changed ? &I : 0;
}
/// EmitGEPOffset - Given a getelementptr instruction/constantexpr, emit the
/// code necessary to compute the offset from the base pointer (without adding
/// in the base pointer). Return the result as a signed integer of intptr size.
static Value *EmitGEPOffset(User *GEP, InstCombiner &IC) {
TargetData &TD = *IC.getTargetData();
gep_type_iterator GTI = gep_type_begin(GEP);
const Type *IntPtrTy = TD.getIntPtrType(GEP->getContext());
Value *Result = Constant::getNullValue(IntPtrTy);
// Build a mask for high order bits.
unsigned IntPtrWidth = TD.getPointerSizeInBits();
uint64_t PtrSizeMask = ~0ULL >> (64-IntPtrWidth);
for (User::op_iterator i = GEP->op_begin() + 1, e = GEP->op_end(); i != e;
++i, ++GTI) {
Value *Op = *i;
uint64_t Size = TD.getTypeAllocSize(GTI.getIndexedType()) & PtrSizeMask;
if (ConstantInt *OpC = dyn_cast<ConstantInt>(Op)) {
if (OpC->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
Size = TD.getStructLayout(STy)->getElementOffset(OpC->getZExtValue());
Result = IC.Builder->CreateAdd(Result,
ConstantInt::get(IntPtrTy, Size),
GEP->getName()+".offs");
continue;
}
Constant *Scale = ConstantInt::get(IntPtrTy, Size);
Constant *OC =
ConstantExpr::getIntegerCast(OpC, IntPtrTy, true /*SExt*/);
Scale = ConstantExpr::getMul(OC, Scale);
// Emit an add instruction.
Result = IC.Builder->CreateAdd(Result, Scale, GEP->getName()+".offs");
continue;
}
// Convert to correct type.
if (Op->getType() != IntPtrTy)
Op = IC.Builder->CreateIntCast(Op, IntPtrTy, true, Op->getName()+".c");
if (Size != 1) {
Constant *Scale = ConstantInt::get(IntPtrTy, Size);
// We'll let instcombine(mul) convert this to a shl if possible.
Op = IC.Builder->CreateMul(Op, Scale, GEP->getName()+".idx");
}
// Emit an add instruction.
Result = IC.Builder->CreateAdd(Op, Result, GEP->getName()+".offs");
}
return Result;
}
/// EvaluateGEPOffsetExpression - Return a value that can be used to compare
/// the *offset* implied by a GEP to zero. For example, if we have &A[i], we
/// want to return 'i' for "icmp ne i, 0". Note that, in general, indices can
/// be complex, and scales are involved. The above expression would also be
/// legal to codegen as "icmp ne (i*4), 0" (assuming A is a pointer to i32).
/// This later form is less amenable to optimization though, and we are allowed
/// to generate the first by knowing that pointer arithmetic doesn't overflow.
///
/// If we can't emit an optimized form for this expression, this returns null.
///
static Value *EvaluateGEPOffsetExpression(User *GEP, Instruction &I,
InstCombiner &IC) {
TargetData &TD = *IC.getTargetData();
gep_type_iterator GTI = gep_type_begin(GEP);
// Check to see if this gep only has a single variable index. If so, and if
// any constant indices are a multiple of its scale, then we can compute this
// in terms of the scale of the variable index. For example, if the GEP
// implies an offset of "12 + i*4", then we can codegen this as "3 + i",
// because the expression will cross zero at the same point.
unsigned i, e = GEP->getNumOperands();
int64_t Offset = 0;
for (i = 1; i != e; ++i, ++GTI) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(i))) {
// Compute the aggregate offset of constant indices.
if (CI->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
Offset += TD.getStructLayout(STy)->getElementOffset(CI->getZExtValue());
} else {
uint64_t Size = TD.getTypeAllocSize(GTI.getIndexedType());
Offset += Size*CI->getSExtValue();
}
} else {
// Found our variable index.
break;
}
}
// If there are no variable indices, we must have a constant offset, just
// evaluate it the general way.
if (i == e) return 0;
Value *VariableIdx = GEP->getOperand(i);
// Determine the scale factor of the variable element. For example, this is
// 4 if the variable index is into an array of i32.
uint64_t VariableScale = TD.getTypeAllocSize(GTI.getIndexedType());
// Verify that there are no other variable indices. If so, emit the hard way.
for (++i, ++GTI; i != e; ++i, ++GTI) {
ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(i));
if (!CI) return 0;
// Compute the aggregate offset of constant indices.
if (CI->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
Offset += TD.getStructLayout(STy)->getElementOffset(CI->getZExtValue());
} else {
uint64_t Size = TD.getTypeAllocSize(GTI.getIndexedType());
Offset += Size*CI->getSExtValue();
}
}
// Okay, we know we have a single variable index, which must be a
// pointer/array/vector index. If there is no offset, life is simple, return
// the index.
unsigned IntPtrWidth = TD.getPointerSizeInBits();
if (Offset == 0) {
// Cast to intptrty in case a truncation occurs. If an extension is needed,
// we don't need to bother extending: the extension won't affect where the
// computation crosses zero.
if (VariableIdx->getType()->getPrimitiveSizeInBits() > IntPtrWidth)
VariableIdx = new TruncInst(VariableIdx,
TD.getIntPtrType(VariableIdx->getContext()),
VariableIdx->getName(), &I);
return VariableIdx;
}
// Otherwise, there is an index. The computation we will do will be modulo
// the pointer size, so get it.
uint64_t PtrSizeMask = ~0ULL >> (64-IntPtrWidth);
Offset &= PtrSizeMask;
VariableScale &= PtrSizeMask;
// To do this transformation, any constant index must be a multiple of the
// variable scale factor. For example, we can evaluate "12 + 4*i" as "3 + i",
// but we can't evaluate "10 + 3*i" in terms of i. Check that the offset is a
// multiple of the variable scale.
int64_t NewOffs = Offset / (int64_t)VariableScale;
if (Offset != NewOffs*(int64_t)VariableScale)
return 0;
// Okay, we can do this evaluation. Start by converting the index to intptr.
const Type *IntPtrTy = TD.getIntPtrType(VariableIdx->getContext());
if (VariableIdx->getType() != IntPtrTy)
VariableIdx = CastInst::CreateIntegerCast(VariableIdx, IntPtrTy,
true /*SExt*/,
VariableIdx->getName(), &I);
Constant *OffsetVal = ConstantInt::get(IntPtrTy, NewOffs);
return BinaryOperator::CreateAdd(VariableIdx, OffsetVal, "offset", &I);
}
/// Optimize pointer differences into the same array into a size. Consider:
/// &A[10] - &A[0]: we should compile this to "10". LHS/RHS are the pointer
/// operands to the ptrtoint instructions for the LHS/RHS of the subtract.
///
Value *InstCombiner::OptimizePointerDifference(Value *LHS, Value *RHS,
const Type *Ty) {
assert(TD && "Must have target data info for this");
// If LHS is a gep based on RHS or RHS is a gep based on LHS, we can optimize
// this.
bool Swapped;
GetElementPtrInst *GEP;
if ((GEP = dyn_cast<GetElementPtrInst>(LHS)) &&
GEP->getOperand(0) == RHS)
Swapped = false;
else if ((GEP = dyn_cast<GetElementPtrInst>(RHS)) &&
GEP->getOperand(0) == LHS)
Swapped = true;
else
return 0;
// TODO: Could also optimize &A[i] - &A[j] -> "i-j".
// Emit the offset of the GEP and an intptr_t.
Value *Result = EmitGEPOffset(GEP, *this);
// If we have p - gep(p, ...) then we have to negate the result.
if (Swapped)
Result = Builder->CreateNeg(Result, "diff.neg");
return Builder->CreateIntCast(Result, Ty, true);
}
Instruction *InstCombiner::visitSub(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Op0 == Op1) // sub X, X -> 0
return ReplaceInstUsesWith(I, Constant::getNullValue(I.getType()));
// If this is a 'B = x-(-A)', change to B = x+A...
// If this is a 'B = x-(-A)', change to B = x+A.
if (Value *V = dyn_castNegVal(Op1))
return BinaryOperator::CreateAdd(Op0, V);
@ -2533,9 +2731,11 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
return ReplaceInstUsesWith(I, Op0); // undef - X -> undef
if (isa<UndefValue>(Op1))
return ReplaceInstUsesWith(I, Op1); // X - undef -> undef
if (I.getType() == Type::getInt1Ty(*Context))
return BinaryOperator::CreateXor(Op0, Op1);
if (ConstantInt *C = dyn_cast<ConstantInt>(Op0)) {
// Replace (-1 - A) with (~A)...
// Replace (-1 - A) with (~A).
if (C->isAllOnesValue())
return BinaryOperator::CreateNot(Op1);
@ -2558,8 +2758,7 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
SI->getOperand(0), CU, SI->getName());
}
}
}
else if (SI->getOpcode() == Instruction::AShr) {
} else if (SI->getOpcode() == Instruction::AShr) {
if (ConstantInt *CU = dyn_cast<ConstantInt>(SI->getOperand(1))) {
// Check to see if we are shifting out everything but the sign bit.
if (CU->getLimitedValue(SI->getType()->getPrimitiveSizeInBits()) ==
@ -2584,9 +2783,6 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
return SelectInst::Create(ZI->getOperand(0), SubOne(C), C);
}
if (I.getType() == Type::getInt1Ty(*Context))
return BinaryOperator::CreateXor(Op0, Op1);
if (BinaryOperator *Op1I = dyn_cast<BinaryOperator>(Op1)) {
if (Op1I->getOpcode() == Instruction::Add) {
if (Op1I->getOperand(0) == Op0) // X-(X+Y) == -Y
@ -2668,6 +2864,28 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
if (X == dyn_castFoldableMul(Op1, C2))
return BinaryOperator::CreateMul(X, ConstantExpr::getSub(C1, C2));
}
// Optimize pointer differences into the same array into a size. Consider:
// &A[10] - &A[0]: we should compile this to "10".
if (TD) {
if (PtrToIntInst *LHS = dyn_cast<PtrToIntInst>(Op0))
if (PtrToIntInst *RHS = dyn_cast<PtrToIntInst>(Op1))
if (Value *Res = OptimizePointerDifference(LHS->getOperand(0),
RHS->getOperand(0),
I.getType()))
return ReplaceInstUsesWith(I, Res);
// trunc(p)-trunc(q) -> trunc(p-q)
if (TruncInst *LHST = dyn_cast<TruncInst>(Op0))
if (TruncInst *RHST = dyn_cast<TruncInst>(Op1))
if (PtrToIntInst *LHS = dyn_cast<PtrToIntInst>(LHST->getOperand(0)))
if (PtrToIntInst *RHS = dyn_cast<PtrToIntInst>(RHST->getOperand(0)))
if (Value *Res = OptimizePointerDifference(LHS->getOperand(0),
RHS->getOperand(0),
I.getType()))
return ReplaceInstUsesWith(I, Res);
}
return 0;
}
@ -5417,166 +5635,6 @@ static bool SubWithOverflow(Constant *&Result, Constant *In1,
IsSigned);
}
/// EmitGEPOffset - Given a getelementptr instruction/constantexpr, emit the
/// code necessary to compute the offset from the base pointer (without adding
/// in the base pointer). Return the result as a signed integer of intptr size.
static Value *EmitGEPOffset(User *GEP, Instruction &I, InstCombiner &IC) {
TargetData &TD = *IC.getTargetData();
gep_type_iterator GTI = gep_type_begin(GEP);
const Type *IntPtrTy = TD.getIntPtrType(I.getContext());
Value *Result = Constant::getNullValue(IntPtrTy);
// Build a mask for high order bits.
unsigned IntPtrWidth = TD.getPointerSizeInBits();
uint64_t PtrSizeMask = ~0ULL >> (64-IntPtrWidth);
for (User::op_iterator i = GEP->op_begin() + 1, e = GEP->op_end(); i != e;
++i, ++GTI) {
Value *Op = *i;
uint64_t Size = TD.getTypeAllocSize(GTI.getIndexedType()) & PtrSizeMask;
if (ConstantInt *OpC = dyn_cast<ConstantInt>(Op)) {
if (OpC->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
Size = TD.getStructLayout(STy)->getElementOffset(OpC->getZExtValue());
Result = IC.Builder->CreateAdd(Result,
ConstantInt::get(IntPtrTy, Size),
GEP->getName()+".offs");
continue;
}
Constant *Scale = ConstantInt::get(IntPtrTy, Size);
Constant *OC =
ConstantExpr::getIntegerCast(OpC, IntPtrTy, true /*SExt*/);
Scale = ConstantExpr::getMul(OC, Scale);
// Emit an add instruction.
Result = IC.Builder->CreateAdd(Result, Scale, GEP->getName()+".offs");
continue;
}
// Convert to correct type.
if (Op->getType() != IntPtrTy)
Op = IC.Builder->CreateIntCast(Op, IntPtrTy, true, Op->getName()+".c");
if (Size != 1) {
Constant *Scale = ConstantInt::get(IntPtrTy, Size);
// We'll let instcombine(mul) convert this to a shl if possible.
Op = IC.Builder->CreateMul(Op, Scale, GEP->getName()+".idx");
}
// Emit an add instruction.
Result = IC.Builder->CreateAdd(Op, Result, GEP->getName()+".offs");
}
return Result;
}
/// EvaluateGEPOffsetExpression - Return a value that can be used to compare
/// the *offset* implied by a GEP to zero. For example, if we have &A[i], we
/// want to return 'i' for "icmp ne i, 0". Note that, in general, indices can
/// be complex, and scales are involved. The above expression would also be
/// legal to codegen as "icmp ne (i*4), 0" (assuming A is a pointer to i32).
/// This later form is less amenable to optimization though, and we are allowed
/// to generate the first by knowing that pointer arithmetic doesn't overflow.
///
/// If we can't emit an optimized form for this expression, this returns null.
///
static Value *EvaluateGEPOffsetExpression(User *GEP, Instruction &I,
InstCombiner &IC) {
TargetData &TD = *IC.getTargetData();
gep_type_iterator GTI = gep_type_begin(GEP);
// Check to see if this gep only has a single variable index. If so, and if
// any constant indices are a multiple of its scale, then we can compute this
// in terms of the scale of the variable index. For example, if the GEP
// implies an offset of "12 + i*4", then we can codegen this as "3 + i",
// because the expression will cross zero at the same point.
unsigned i, e = GEP->getNumOperands();
int64_t Offset = 0;
for (i = 1; i != e; ++i, ++GTI) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(i))) {
// Compute the aggregate offset of constant indices.
if (CI->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
Offset += TD.getStructLayout(STy)->getElementOffset(CI->getZExtValue());
} else {
uint64_t Size = TD.getTypeAllocSize(GTI.getIndexedType());
Offset += Size*CI->getSExtValue();
}
} else {
// Found our variable index.
break;
}
}
// If there are no variable indices, we must have a constant offset, just
// evaluate it the general way.
if (i == e) return 0;
Value *VariableIdx = GEP->getOperand(i);
// Determine the scale factor of the variable element. For example, this is
// 4 if the variable index is into an array of i32.
uint64_t VariableScale = TD.getTypeAllocSize(GTI.getIndexedType());
// Verify that there are no other variable indices. If so, emit the hard way.
for (++i, ++GTI; i != e; ++i, ++GTI) {
ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(i));
if (!CI) return 0;
// Compute the aggregate offset of constant indices.
if (CI->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
Offset += TD.getStructLayout(STy)->getElementOffset(CI->getZExtValue());
} else {
uint64_t Size = TD.getTypeAllocSize(GTI.getIndexedType());
Offset += Size*CI->getSExtValue();
}
}
// Okay, we know we have a single variable index, which must be a
// pointer/array/vector index. If there is no offset, life is simple, return
// the index.
unsigned IntPtrWidth = TD.getPointerSizeInBits();
if (Offset == 0) {
// Cast to intptrty in case a truncation occurs. If an extension is needed,
// we don't need to bother extending: the extension won't affect where the
// computation crosses zero.
if (VariableIdx->getType()->getPrimitiveSizeInBits() > IntPtrWidth)
VariableIdx = new TruncInst(VariableIdx,
TD.getIntPtrType(VariableIdx->getContext()),
VariableIdx->getName(), &I);
return VariableIdx;
}
// Otherwise, there is an index. The computation we will do will be modulo
// the pointer size, so get it.
uint64_t PtrSizeMask = ~0ULL >> (64-IntPtrWidth);
Offset &= PtrSizeMask;
VariableScale &= PtrSizeMask;
// To do this transformation, any constant index must be a multiple of the
// variable scale factor. For example, we can evaluate "12 + 4*i" as "3 + i",
// but we can't evaluate "10 + 3*i" in terms of i. Check that the offset is a
// multiple of the variable scale.
int64_t NewOffs = Offset / (int64_t)VariableScale;
if (Offset != NewOffs*(int64_t)VariableScale)
return 0;
// Okay, we can do this evaluation. Start by converting the index to intptr.
const Type *IntPtrTy = TD.getIntPtrType(VariableIdx->getContext());
if (VariableIdx->getType() != IntPtrTy)
VariableIdx = CastInst::CreateIntegerCast(VariableIdx, IntPtrTy,
true /*SExt*/,
VariableIdx->getName(), &I);
Constant *OffsetVal = ConstantInt::get(IntPtrTy, NewOffs);
return BinaryOperator::CreateAdd(VariableIdx, OffsetVal, "offset", &I);
}
/// FoldGEPICmp - Fold comparisons between a GEP instruction and something
/// else. At this point we know that the GEP is on the LHS of the comparison.
@ -5597,7 +5655,7 @@ Instruction *InstCombiner::FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
// If not, synthesize the offset the hard way.
if (Offset == 0)
Offset = EmitGEPOffset(GEPLHS, I, *this);
Offset = EmitGEPOffset(GEPLHS, *this);
return new ICmpInst(ICmpInst::getSignedPredicate(Cond), Offset,
Constant::getNullValue(Offset->getType()));
} else if (GEPOperator *GEPRHS = dyn_cast<GEPOperator>(RHS)) {
@ -5683,8 +5741,8 @@ Instruction *InstCombiner::FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
(isa<ConstantExpr>(GEPLHS) || GEPLHS->hasOneUse()) &&
(isa<ConstantExpr>(GEPRHS) || GEPRHS->hasOneUse())) {
// ((gep Ptr, OFFSET1) cmp (gep Ptr, OFFSET2) ---> (OFFSET1 cmp OFFSET2)
Value *L = EmitGEPOffset(GEPLHS, I, *this);
Value *R = EmitGEPOffset(GEPRHS, I, *this);
Value *L = EmitGEPOffset(GEPLHS, *this);
Value *R = EmitGEPOffset(GEPRHS, *this);
return new ICmpInst(ICmpInst::getSignedPredicate(Cond), L, R);
}
}
@ -8201,8 +8259,7 @@ Instruction *InstCombiner::commonPointerCastTransforms(CastInst &CI) {
if (TD && GEP->hasOneUse() && isa<BitCastInst>(GEP->getOperand(0))) {
if (GEP->hasAllConstantIndices()) {
// We are guaranteed to get a constant from EmitGEPOffset.
ConstantInt *OffsetV =
cast<ConstantInt>(EmitGEPOffset(GEP, CI, *this));
ConstantInt *OffsetV = cast<ConstantInt>(EmitGEPOffset(GEP, *this));
int64_t Offset = OffsetV->getSExtValue();
// Get the base pointer input of the bitcast, and the type it points to.
@ -11310,8 +11367,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
!isa<BitCastInst>(BCI->getOperand(0)) && GEP.hasAllConstantIndices()) {
// Determine how much the GEP moves the pointer. We are guaranteed to get
// a constant back from EmitGEPOffset.
ConstantInt *OffsetV =
cast<ConstantInt>(EmitGEPOffset(&GEP, GEP, *this));
ConstantInt *OffsetV = cast<ConstantInt>(EmitGEPOffset(&GEP, *this));
int64_t Offset = OffsetV->getSExtValue();
// If this GEP instruction doesn't move the pointer, just replace the GEP

39
test/Transforms/InstCombine/sub.ll
View File

@ -1,4 +1,6 @@
; This test makes sure that these instructions are properly eliminated.
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"
; Optimize subtracts.
;
; RUN: opt < %s -instcombine -S | FileCheck %s
@ -211,3 +213,38 @@ define i1 @test22(i32 %a, i32 %b) zeroext nounwind {
; CHECK: ret i1 %tmp5
}
; rdar://7362831
define i32 @test23(i8* %P, i64 %A){
%B = getelementptr inbounds i8* %P, i64 %A
%C = ptrtoint i8* %B to i64
%D = trunc i64 %C to i32
%E = ptrtoint i8* %P to i64
%F = trunc i64 %E to i32
%G = sub i32 %D, %F
ret i32 %G
; CHECK: @test23
; CHECK: %A1 = trunc i64 %A to i32
; CHECK: ret i32 %A1
}
define i64 @test24(i8* %P, i64 %A){
%B = getelementptr inbounds i8* %P, i64 %A
%C = ptrtoint i8* %B to i64
%E = ptrtoint i8* %P to i64
%G = sub i64 %C, %E
ret i64 %G
; CHECK: @test24
; CHECK-NEXT: ret i64 %A
}
define i64 @test24a(i8* %P, i64 %A){
%B = getelementptr inbounds i8* %P, i64 %A
%C = ptrtoint i8* %B to i64
%E = ptrtoint i8* %P to i64
%G = sub i64 %E, %C
ret i64 %G
; CHECK: @test24a
; CHECK-NEXT: sub i64 0, %A
; CHECK-NEXT: ret i64
}