Index: llvm/lib/Analysis/LoopAccessAnalysis.cpp =================================================================== --- llvm/lib/Analysis/LoopAccessAnalysis.cpp +++ llvm/lib/Analysis/LoopAccessAnalysis.cpp @@ -1445,13 +1445,13 @@ const SCEV *CastedDist = &Dist; const SCEV *CastedProduct = Product; - uint64_t DistTypeSize = DL.getTypeAllocSize(Dist.getType()); - uint64_t ProductTypeSize = DL.getTypeAllocSize(Product->getType()); + uint64_t DistTypeSizeBits = DL.getTypeSizeInBits(Dist.getType()); + uint64_t ProductTypeSizeBits = DL.getTypeSizeInBits(Product->getType()); // The dependence distance can be positive/negative, so we sign extend Dist; // The multiplication of the absolute stride in bytes and the // backedgeTakenCount is non-negative, so we zero extend Product. - if (DistTypeSize > ProductTypeSize) + if (DistTypeSizeBits > ProductTypeSizeBits) CastedProduct = SE.getZeroExtendExpr(Product, Dist.getType()); else CastedDist = SE.getNoopOrSignExtend(&Dist, Product->getType()); @@ -2260,12 +2260,12 @@ // The Stride can be positive/negative, so we sign extend Stride; // The backedgeTakenCount is non-negative, so we zero extend BETakenCount. const DataLayout &DL = TheLoop->getHeader()->getModule()->getDataLayout(); - uint64_t StrideTypeSize = DL.getTypeAllocSize(StrideExpr->getType()); - uint64_t BETypeSize = DL.getTypeAllocSize(BETakenCount->getType()); + uint64_t StrideTypeSizeBits = DL.getTypeSizeInBits(StrideExpr->getType()); + uint64_t BETypeSizeBits = DL.getTypeSizeInBits(BETakenCount->getType()); const SCEV *CastedStride = StrideExpr; const SCEV *CastedBECount = BETakenCount; ScalarEvolution *SE = PSE->getSE(); - if (BETypeSize >= StrideTypeSize) + if (BETypeSizeBits >= StrideTypeSizeBits) CastedStride = SE->getNoopOrSignExtend(StrideExpr, BETakenCount->getType()); else CastedBECount = SE->getZeroExtendExpr(BETakenCount, StrideExpr->getType()); Index: llvm/test/Transforms/LoopLoadElim/loop-i1-count.ll =================================================================== --- /dev/null +++ llvm/test/Transforms/LoopLoadElim/loop-i1-count.ll @@ -0,0 +1,50 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt -S -passes=loop-load-elim %s | FileCheck %s + +; The backedge taken count of this loop is an i1 type, and the IV is i8. +; The math in LoopAccessAnalysis was rounding the type sizes to bytes and +; believing them equal, causing a size mismatch. + +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@a = external dso_local local_unnamed_addr global [1 x i32], align 4 + +define dso_local void @test() local_unnamed_addr { +; CHECK-LABEL: @test( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[FOR_COND3:%.*]] +; CHECK: for.cond3: +; CHECK-NEXT: [[H_0:%.*]] = phi i8 [ undef, [[ENTRY:%.*]] ], [ [[ADD:%.*]], [[COND_END_FOR_COND_CLEANUP_LOOPEXIT_CRIT_EDGE:%.*]] ] +; CHECK-NEXT: [[IDXPROM11:%.*]] = sext i8 [[H_0]] to i64 +; CHECK-NEXT: [[ARRAYIDX27:%.*]] = getelementptr inbounds [1 x i32], [1 x i32]* @a, i64 0, i64 [[IDXPROM11]] +; CHECK-NEXT: br label [[FOR_BODY:%.*]] +; CHECK: cond.end.for.cond.cleanup.loopexit_crit_edge: +; CHECK-NEXT: [[ADD]] = add i8 [[H_0]], undef +; CHECK-NEXT: br label [[FOR_COND3]] +; CHECK: for.body: +; CHECK-NEXT: store i32 0, i32* [[ARRAYIDX27]], align 4 +; CHECK-NEXT: [[TMP0:%.*]] = or i1 true, undef +; CHECK-NEXT: br i1 [[TMP0]], label [[COND_END_FOR_COND_CLEANUP_LOOPEXIT_CRIT_EDGE]], label [[FOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]] +; +entry: + br label %for.cond3 + +for.cond3: ; preds = %cond.end.for.cond.cleanup.loopexit_crit_edge, %entry + %h.0 = phi i8 [ undef, %entry ], [ %add, %cond.end.for.cond.cleanup.loopexit_crit_edge ] + %idxprom11 = sext i8 %h.0 to i64 + %arrayidx27 = getelementptr inbounds [1 x i32], [1 x i32]* @a, i64 0, i64 %idxprom11 + br label %for.body + +cond.end.for.cond.cleanup.loopexit_crit_edge: ; preds = %for.body + %add = add i8 %h.0, undef + br label %for.cond3 + +for.body: ; preds = %for.body, %for.cond3 + store i32 0, i32* %arrayidx27, align 4 + %0 = or i1 true, undef + br i1 %0, label %cond.end.for.cond.cleanup.loopexit_crit_edge, label %for.body, !llvm.loop !1 +} + +!1 = distinct !{!1, !2} +!2 = !{!"llvm.loop.mustprogress"}