Index: llvm/lib/Transforms/Vectorize/LoopVectorize.cpp =================================================================== --- llvm/lib/Transforms/Vectorize/LoopVectorize.cpp +++ llvm/lib/Transforms/Vectorize/LoopVectorize.cpp @@ -5481,11 +5481,9 @@ return None; } - ElementCount MaxVF = computeFeasibleMaxVF(TC, UserVF); - switch (ScalarEpilogueStatus) { case CM_ScalarEpilogueAllowed: - return MaxVF; + return computeFeasibleMaxVF(TC, UserVF); case CM_ScalarEpilogueNotAllowedUsePredicate: LLVM_FALLTHROUGH; case CM_ScalarEpilogueNotNeededUsePredicate: @@ -5523,7 +5521,7 @@ LLVM_DEBUG(dbgs() << "LV: Cannot fold tail by masking: vectorize with a " "scalar epilogue instead.\n"); ScalarEpilogueStatus = CM_ScalarEpilogueAllowed; - return MaxVF; + return computeFeasibleMaxVF(TC, UserVF); } return None; } @@ -5540,6 +5538,7 @@ InterleaveInfo.invalidateGroupsRequiringScalarEpilogue(); } + ElementCount MaxVF = computeFeasibleMaxVF(TC, UserVF); assert(!MaxVF.isScalable() && "Scalable vectors do not yet support tail folding"); assert((UserVF.isNonZero() || isPowerOf2_32(MaxVF.getFixedValue())) && Index: llvm/test/Transforms/LoopVectorize/Hexagon/maximum-vf-crash.ll =================================================================== --- /dev/null +++ llvm/test/Transforms/LoopVectorize/Hexagon/maximum-vf-crash.ll @@ -0,0 +1,29 @@ +; RUN: opt -march=hexagon -hexagon-autohvx -loop-vectorize -S < %s 2>&1 | FileCheck %s + +; Check that we don't crash. + +; CHECK-LABEL: @f +; CHECK: vector.body + +target datalayout = "e-m:e-p:32:32:32-a:0-n16:32-i64:64:64-i32:32:32-i16:16:16-i1:8:8-f32:32:32-f64:64:64-v32:32:32-v64:64:64-v512:512:512-v1024:1024:1024-v2048:2048:2048" +target triple = "hexagon" + +; Function Attrs: optsize +define i32 @f() #0 { +entry: + br label %loop + +loop: + %g.016 = phi i32 [ 0, %entry ], [ %g.1.lcssa, %loop ] + %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ] + %0 = load i8, i8* undef, align 1 + %g.1.lcssa = add i32 %g.016, undef + %iv.next = add nsw i32 %iv, 1 + %exitcond = icmp eq i32 %iv.next, 0 + br i1 %exitcond, label %exit, label %loop + +exit: + ret i32 %g.1.lcssa +} + +attributes #0 = { optsize "target-features"="+hvx-length128b" }