Teach ScalarEvolution about pointer address spaces

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190425 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Matt Arsenault 2013-09-10 19:55:24 +00:00
parent be5faa8a1e
commit 14807bd8c8
5 changed files with 101 additions and 20 deletions

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@ -636,21 +636,24 @@ namespace llvm {
const SCEV *getUnknown(Value *V);
const SCEV *getCouldNotCompute();
/// getSizeOfExpr - Return an expression for sizeof on the given type.
/// getSizeOfExpr - Return an expression for sizeof AllocTy that is type
/// IntTy
///
const SCEV *getSizeOfExpr(Type *AllocTy);
const SCEV *getSizeOfExpr(Type *IntTy, Type *AllocTy);
/// getAlignOfExpr - Return an expression for alignof on the given type.
/// getAlignOfExpr - Return an expression for alignof AllocTy
///
const SCEV *getAlignOfExpr(Type *AllocTy);
/// getOffsetOfExpr - Return an expression for offsetof on the given field.
/// getOffsetOfExpr - Return an expression for offsetof on the given field
/// with type IntTy
///
const SCEV *getOffsetOfExpr(StructType *STy, unsigned FieldNo);
const SCEV *getOffsetOfExpr(Type *IntTy, StructType *STy, unsigned FieldNo);
/// getOffsetOfExpr - Return an expression for offsetof on the given field.
/// getOffsetOfExpr - Return an expression for offsetof on the given field
/// that is type IntTy
///
const SCEV *getOffsetOfExpr(Type *CTy, Constant *FieldNo);
const SCEV *getOffsetOfExpr(Type *IntTy, Type *CTy, Constant *FieldNo);
/// getNegativeSCEV - Return the SCEV object corresponding to -V.
///

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@ -2590,19 +2590,19 @@ const SCEV *ScalarEvolution::getUMinExpr(const SCEV *LHS,
return getNotSCEV(getUMaxExpr(getNotSCEV(LHS), getNotSCEV(RHS)));
}
const SCEV *ScalarEvolution::getSizeOfExpr(Type *AllocTy) {
const SCEV *ScalarEvolution::getSizeOfExpr(Type *IntTy, Type *AllocTy) {
// If we have DataLayout, we can bypass creating a target-independent
// constant expression and then folding it back into a ConstantInt.
// This is just a compile-time optimization.
if (TD)
return getConstant(TD->getIntPtrType(getContext()),
TD->getTypeAllocSize(AllocTy));
return getConstant(IntTy, TD->getTypeAllocSize(AllocTy));
Constant *C = ConstantExpr::getSizeOf(AllocTy);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
if (Constant *Folded = ConstantFoldConstantExpression(CE, TD, TLI))
C = Folded;
Type *Ty = getEffectiveSCEVType(PointerType::getUnqual(AllocTy));
assert(Ty == IntTy && "Effective SCEV type doesn't match");
return getTruncateOrZeroExtend(getSCEV(C), Ty);
}
@ -2615,14 +2615,16 @@ const SCEV *ScalarEvolution::getAlignOfExpr(Type *AllocTy) {
return getTruncateOrZeroExtend(getSCEV(C), Ty);
}
const SCEV *ScalarEvolution::getOffsetOfExpr(StructType *STy,
const SCEV *ScalarEvolution::getOffsetOfExpr(Type *IntTy,
StructType *STy,
unsigned FieldNo) {
// If we have DataLayout, we can bypass creating a target-independent
// constant expression and then folding it back into a ConstantInt.
// This is just a compile-time optimization.
if (TD)
return getConstant(TD->getIntPtrType(getContext()),
if (TD) {
return getConstant(IntTy,
TD->getStructLayout(STy)->getElementOffset(FieldNo));
}
Constant *C = ConstantExpr::getOffsetOf(STy, FieldNo);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
@ -2632,7 +2634,8 @@ const SCEV *ScalarEvolution::getOffsetOfExpr(StructType *STy,
return getTruncateOrZeroExtend(getSCEV(C), Ty);
}
const SCEV *ScalarEvolution::getOffsetOfExpr(Type *CTy,
const SCEV *ScalarEvolution::getOffsetOfExpr(Type *IntTy,
Type *CTy,
Constant *FieldNo) {
Constant *C = ConstantExpr::getOffsetOf(CTy, FieldNo);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
@ -2703,12 +2706,15 @@ uint64_t ScalarEvolution::getTypeSizeInBits(Type *Ty) const {
Type *ScalarEvolution::getEffectiveSCEVType(Type *Ty) const {
assert(isSCEVable(Ty) && "Type is not SCEVable!");
if (Ty->isIntegerTy())
if (Ty->isIntegerTy()) {
return Ty;
}
// The only other support type is pointer.
assert(Ty->isPointerTy() && "Unexpected non-pointer non-integer type!");
if (TD) return TD->getIntPtrType(getContext());
if (TD)
return TD->getIntPtrType(Ty);
// Without DataLayout, conservatively assume pointers are 64-bit.
return Type::getInt64Ty(getContext());
@ -3199,13 +3205,13 @@ const SCEV *ScalarEvolution::createNodeForGEP(GEPOperator *GEP) {
if (StructType *STy = dyn_cast<StructType>(*GTI++)) {
// For a struct, add the member offset.
unsigned FieldNo = cast<ConstantInt>(Index)->getZExtValue();
const SCEV *FieldOffset = getOffsetOfExpr(STy, FieldNo);
const SCEV *FieldOffset = getOffsetOfExpr(IntPtrTy, STy, FieldNo);
// Add the field offset to the running total offset.
TotalOffset = getAddExpr(TotalOffset, FieldOffset);
} else {
// For an array, add the element offset, explicitly scaled.
const SCEV *ElementSize = getSizeOfExpr(*GTI);
const SCEV *ElementSize = getSizeOfExpr(IntPtrTy, *GTI);
const SCEV *IndexS = getSCEV(Index);
// Getelementptr indices are signed.
IndexS = getTruncateOrSignExtend(IndexS, IntPtrTy);

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@ -407,6 +407,10 @@ Value *SCEVExpander::expandAddToGEP(const SCEV *const *op_begin,
// without the other.
SplitAddRecs(Ops, Ty, SE);
Type *IntPtrTy = SE.TD
? SE.TD->getIntPtrType(PTy)
: Type::getInt64Ty(PTy->getContext());
// Descend down the pointer's type and attempt to convert the other
// operands into GEP indices, at each level. The first index in a GEP
// indexes into the array implied by the pointer operand; the rest of
@ -417,7 +421,7 @@ Value *SCEVExpander::expandAddToGEP(const SCEV *const *op_begin,
// array indexing.
SmallVector<const SCEV *, 8> ScaledOps;
if (ElTy->isSized()) {
const SCEV *ElSize = SE.getSizeOfExpr(ElTy);
const SCEV *ElSize = SE.getSizeOfExpr(IntPtrTy, ElTy);
if (!ElSize->isZero()) {
SmallVector<const SCEV *, 8> NewOps;
for (unsigned i = 0, e = Ops.size(); i != e; ++i) {

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@ -1492,7 +1492,7 @@ static Value *genLoopLimit(PHINode *IndVar, const SCEV *IVCount, Loop *L,
assert(AR->getStart() == SE->getSCEV(GEPBase) && "bad loop counter");
// We could handle pointer IVs other than i8*, but we need to compensate for
// gep index scaling. See canExpandBackedgeTakenCount comments.
assert(SE->getSizeOfExpr(
assert(SE->getSizeOfExpr(IntegerType::getInt64Ty(IndVar->getContext()),
cast<PointerType>(GEPBase->getType())->getElementType())->isOne()
&& "unit stride pointer IV must be i8*");

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@ -0,0 +1,68 @@
; RUN: opt < %s -analyze -scalar-evolution | FileCheck %s
; ScalarEvolution should be able to understand the loop and eliminate the casts.
target datalayout = "e-p:32:32:32-p1:16:16:16-p2:8:8:8-p4:64:64:64-n16:32:64"
; CHECK: {%d,+,4}<%bb> Exits: ((4 * (trunc i32 (-1 + %n) to i16)) + %d)
define void @foo(i32 addrspace(1)* nocapture %d, i32 %n) nounwind {
; CHECK: @foo
entry:
%0 = icmp sgt i32 %n, 0 ; <i1> [#uses=1]
br i1 %0, label %bb.nph, label %return
bb.nph: ; preds = %entry
br label %bb
bb: ; preds = %bb1, %bb.nph
%i.02 = phi i32 [ %5, %bb1 ], [ 0, %bb.nph ] ; <i32> [#uses=2]
%p.01 = phi i8 [ %4, %bb1 ], [ -1, %bb.nph ] ; <i8> [#uses=2]
%1 = sext i8 %p.01 to i32 ; <i32> [#uses=1]
%2 = sext i32 %i.02 to i64 ; <i64> [#uses=1]
%3 = getelementptr i32 addrspace(1)* %d, i64 %2 ; <i32*> [#uses=1]
store i32 %1, i32 addrspace(1)* %3, align 4
%4 = add i8 %p.01, 1 ; <i8> [#uses=1]
%5 = add i32 %i.02, 1 ; <i32> [#uses=2]
br label %bb1
bb1: ; preds = %bb
%6 = icmp slt i32 %5, %n ; <i1> [#uses=1]
br i1 %6, label %bb, label %bb1.return_crit_edge
bb1.return_crit_edge: ; preds = %bb1
br label %return
return: ; preds = %bb1.return_crit_edge, %entry
ret void
}
define void @test(i8 addrspace(1)* %a, i32 %n) nounwind {
; CHECK: @test
entry:
%cmp1 = icmp sgt i32 %n, 0
br i1 %cmp1, label %for.body.lr.ph, label %for.end
for.body.lr.ph: ; preds = %entry
%tmp = zext i32 %n to i64
br label %for.body
for.body: ; preds = %for.body, %for.body.lr.ph
%indvar = phi i64 [ %indvar.next, %for.body ], [ 0, %for.body.lr.ph ]
%arrayidx = getelementptr i8 addrspace(1)* %a, i64 %indvar
store i8 0, i8 addrspace(1)* %arrayidx, align 1
%indvar.next = add i64 %indvar, 1
%exitcond = icmp ne i64 %indvar.next, %tmp
br i1 %exitcond, label %for.body, label %for.cond.for.end_crit_edge
for.cond.for.end_crit_edge: ; preds = %for.body
br label %for.end
for.end: ; preds = %for.cond.for.end_crit_edge, %entry
ret void
}
; CHECK: Determining loop execution counts for: @test
; CHECK-NEXT: backedge-taken count is
; CHECK-NEXT: max backedge-taken count is -1