LFTR should avoid a type mismatch with null pointer IVs.

Fixes rdar://10359193 Indvar LinearFunctionTestReplace assertion


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143183 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Andrew Trick 2011-10-28 03:45:11 +00:00
parent 3799efab8c
commit 6f2dd7ebcf
2 changed files with 76 additions and 15 deletions

View File

@ -1558,8 +1558,7 @@ LinearFunctionTestReplace(Loop *L,
}
// For unit stride, IVLimit = Start + BECount with 2's complement overflow.
// So for, non-zero start compute the IVLimit here.
bool isPtrIV = false;
// So for non-zero start compute the IVLimit here.
Type *CmpTy = CntTy;
const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(SE->getSCEV(IndVar));
assert(AR && AR->getLoop() == L && AR->isAffine() && "bad loop counter");
@ -1571,8 +1570,7 @@ LinearFunctionTestReplace(Loop *L,
// Note that for without EnableIVRewrite, we never run SCEVExpander on a
// pointer type, because we must preserve the existing GEPs. Instead we
// directly generate a GEP later.
if (IVInit->getType()->isPointerTy()) {
isPtrIV = true;
if (CmpIndVar->getType()->isPointerTy()) {
CmpTy = SE->getEffectiveSCEVType(IVInit->getType());
IVLimit = SE->getTruncateOrSignExtend(IVLimit, CmpTy);
}
@ -1590,21 +1588,25 @@ LinearFunctionTestReplace(Loop *L,
assert(SE->isLoopInvariant(IVLimit, L) &&
"Computed iteration count is not loop invariant!");
assert( !IVLimit->getType()->isPointerTy() &&
"Should not expand pointer types" );
Value *ExitCnt = Rewriter.expandCodeFor(IVLimit, CmpTy, BI);
// Create a gep for IVInit + IVLimit from on an existing pointer base.
assert(isPtrIV == IndVar->getType()->isPointerTy() &&
"IndVar type must match IVInit type");
if (isPtrIV) {
Value *IVStart = IndVar->getIncomingValueForBlock(L->getLoopPreheader());
assert(AR->getStart() == SE->getSCEV(IVStart) && "bad loop counter");
assert(SE->getSizeOfExpr(
cast<PointerType>(IVStart->getType())->getElementType())->isOne()
&& "unit stride pointer IV must be i8*");
//
// In the presence of null pointer values, the SCEV expression may be an
// integer type while the IV is a pointer type. Ensure that the compare
// operands are always the same type by checking the IV type here.
if (CmpIndVar->getType()->isPointerTy()) {
Value *IVStart = IndVar->getIncomingValueForBlock(L->getLoopPreheader());
assert(AR->getStart() == SE->getSCEV(IVStart) && "bad loop counter");
assert(SE->getSizeOfExpr(
cast<PointerType>(IVStart->getType())->getElementType())->isOne()
&& "unit stride pointer IV must be i8*");
Builder.SetInsertPoint(L->getLoopPreheader()->getTerminator());
ExitCnt = Builder.CreateGEP(IVStart, ExitCnt, "lftr.limit");
Builder.SetInsertPoint(BI);
Builder.SetInsertPoint(L->getLoopPreheader()->getTerminator());
ExitCnt = Builder.CreateGEP(IVStart, ExitCnt, "lftr.limit");
Builder.SetInsertPoint(BI);
}
// Insert a new icmp_ne or icmp_eq instruction before the branch.

View File

@ -0,0 +1,59 @@
; RUN: opt < %s -indvars -S | FileCheck %s
; rdar://10359193: assert "IndVar type must match IVInit type"
target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:32:64-v128:32:128-a0:0:32-n32-S32"
target triple = "thumbv7-apple-darwin"
; CHECK: @test
; CHECK: if.end.i126:
; CHECK: %exitcond = icmp ne i8* %incdec.ptr.i, getelementptr (i8* null, i32 undef)
define void @test() nounwind {
entry:
br label %while.cond
while.cond:
br i1 undef, label %while.end, label %while.body
while.body: ; preds = %while.cond
br i1 undef, label %if.then165, label %while.cond
if.then165: ; preds = %while.body
br i1 undef, label %while.cond, label %for.body.lr.ph.i81
for.body.lr.ph.i81: ; preds = %if.then165
br label %for.body.i86
for.body.i86: ; preds = %for.end.i129, %for.body.lr.ph.i81
%cmp196.i = icmp ult i32 0, undef
br i1 %cmp196.i, label %for.body21.lr.ph.i, label %for.end.i129
for.body21.lr.ph.i: ; preds = %for.body.i86
br label %for.body21.i
for.body21.i:
%destYPixelPtr.010.i = phi i8* [ null, %for.body21.lr.ph.i ], [ %incdec.ptr.i, %if.end.i126 ]
%x.09.i = phi i32 [ 0, %for.body21.lr.ph.i ], [ %inc.i125, %if.end.i126 ]
br i1 undef, label %if.end.i126, label %if.else.i124
if.else.i124: ; preds = %for.body21.i
store i8 undef, i8* %destYPixelPtr.010.i, align 1
br label %if.end.i126
if.end.i126: ; preds = %if.else.i124, %for.body21.i
%incdec.ptr.i = getelementptr inbounds i8* %destYPixelPtr.010.i, i32 1
%inc.i125 = add i32 %x.09.i, 1
%cmp19.i = icmp ult i32 %inc.i125, undef
br i1 %cmp19.i, label %for.body21.i, label %for.end.i129
for.end.i129: ; preds = %if.end.i126, %for.body.i86
br i1 undef, label %for.body.i86, label %while.cond
while.end: ; preds = %while.cond
br label %bail
bail: ; preds = %while.end, %lor.lhs.false44, %lor.lhs.false41, %if.end29, %if.end
unreachable
return: ; preds = %lor.lhs.false20, %lor.lhs.false12, %lor.lhs.false, %entry
ret void
}