Index: polly/trunk/include/polly/Support/SCEVAffinator.h =================================================================== --- polly/trunk/include/polly/Support/SCEVAffinator.h +++ polly/trunk/include/polly/Support/SCEVAffinator.h @@ -118,6 +118,7 @@ PWACtx visitUnknown(const llvm::SCEVUnknown *E); PWACtx visitSDivInstruction(llvm::Instruction *SDiv); PWACtx visitSRemInstruction(llvm::Instruction *SRem); + PWACtx complexityBailout(); friend struct llvm::SCEVVisitor; }; Index: polly/trunk/lib/Support/SCEVAffinator.cpp =================================================================== --- polly/trunk/lib/Support/SCEVAffinator.cpp +++ polly/trunk/lib/Support/SCEVAffinator.cpp @@ -368,7 +368,7 @@ for (int i = 1, e = Expr->getNumOperands(); i < e; ++i) { Sum = combine(Sum, visit(Expr->getOperand(i)), isl_pw_aff_add); if (isTooComplex(Sum)) - return std::make_pair(nullptr, nullptr); + return complexityBailout(); } return Sum; @@ -380,7 +380,7 @@ for (int i = 1, e = Expr->getNumOperands(); i < e; ++i) { Prod = combine(Prod, visit(Expr->getOperand(i)), isl_pw_aff_mul); if (isTooComplex(Prod)) - return std::make_pair(nullptr, nullptr); + return complexityBailout(); } return Prod; @@ -431,7 +431,7 @@ for (int i = 1, e = Expr->getNumOperands(); i < e; ++i) { Max = combine(Max, visit(Expr->getOperand(i)), isl_pw_aff_max); if (isTooComplex(Max)) - return std::make_pair(nullptr, nullptr); + return complexityBailout(); } return Max; @@ -532,3 +532,11 @@ llvm_unreachable( "Unknowns SCEV was neither parameter nor a valid instruction."); } + +PWACtx SCEVAffinator::complexityBailout() { + // We hit the complexity limit for affine expressions; invalidate the scop + // and return a constant zero. + const DebugLoc &Loc = BB ? BB->getTerminator()->getDebugLoc() : DebugLoc(); + S->invalidate(COMPLEXITY, Loc); + return visit(SE.getZero(Type::getInt32Ty(BB->getContext()))); +} Index: polly/trunk/test/ScopInfo/pwaff-complexity-bailout.ll =================================================================== --- polly/trunk/test/ScopInfo/pwaff-complexity-bailout.ll +++ polly/trunk/test/ScopInfo/pwaff-complexity-bailout.ll @@ -0,0 +1,37 @@ +; RUN: opt %loadPolly -analyze -polly-scops -pass-remarks-analysis=.* < %s 2>&1 > /dev/null | FileCheck %s + +; Make sure we hit the complexity bailout, and don't crash. +; CHECK: Low complexity assumption: { : false } + +target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64" +target triple = "thumbv8--linux-android" + +define hidden void @f(i32 %arg1, i32 %arg2, i32 %cond, i32 %tmp, i32 %tmp196) { +entry: + %div = sdiv i32 %tmp, 8 + %div10 = sdiv i32 %arg1, 8 + %div11 = sdiv i32 %tmp196, 2 + %add = add nsw i32 %div10, %div11 + %sub19 = add nsw i32 %div, -1 + %cmp20 = icmp slt i32 %add, %sub19 + %add.sub19 = select i1 %cmp20, i32 %add, i32 %sub19 + %div469 = sdiv i32 %arg2, 8 + %cmp.i68 = icmp slt i32 %div469, %cond + %cond.i = select i1 %cmp.i68, i32 %cond, i32 %div469 + %sub.i69 = add i32 0, %div469 + %cmp9.i = icmp sgt i32 %sub.i69, %add.sub19 + %sub15.max_x.i = select i1 %cmp9.i, i32 %add.sub19, i32 %sub.i69 + %sub30.i = sub nsw i32 %sub15.max_x.i, %cond.i + %add31.i = add nsw i32 %sub30.i, 1 + br label %for.body.us.i + +for.body.us.i: + br label %for.body47.us.i + +for.body47.us.i: + %cmp45.us.i = icmp ult i32 0, %add31.i + br i1 %cmp45.us.i, label %for.body47.us.i, label %for.cond44.for.cond.cleanup46_crit_edge.us.i + +for.cond44.for.cond.cleanup46_crit_edge.us.i: + br label %for.body.us.i +}