diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp --- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp +++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp @@ -4455,6 +4455,14 @@ assert(VF.isVector() && Scalars.find(VF) == Scalars.end() && "This function should not be visited twice for the same VF"); + // This avoids any chances of creating a REPLICATE recipe during planning + // since that would result in generation of scalarized code during execution, + // which is not supported for scalable vectors. + if (VF.isScalable()) { + Scalars[VF].insert(Uniforms[VF].begin(), Uniforms[VF].end()); + return; + } + SmallSetVector Worklist; // These sets are used to seed the analysis with pointers used by memory diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/scalable-avoid-scalarization.ll b/llvm/test/Transforms/LoopVectorize/AArch64/scalable-avoid-scalarization.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/LoopVectorize/AArch64/scalable-avoid-scalarization.ll @@ -0,0 +1,95 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt < %s -mtriple=aarch64 -loop-vectorize --force-vector-interleave=1 -S | FileCheck %s + +target triple = "aarch64-unknown-linux-gnu" + +; The test checks that scalarized code is not generated for SVE. +; It creates a scenario where the gep instruction is used outside +; the loop, preventing the gep (and consequently the loop induction +; update variable) from being classified as 'uniform'. + +define void @test_no_scalarization(i64* %a, i32 %idx, i32 %n) #0 { +; CHECK-LABEL: @test_no_scalarization( +; CHECK-NEXT: L.entry: +; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[IDX:%.*]], 1 +; CHECK-NEXT: [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[N:%.*]], i32 [[TMP0]]) +; CHECK-NEXT: [[TMP1:%.*]] = sub i32 [[SMAX]], [[IDX]] +; CHECK-NEXT: [[TMP2:%.*]] = call i32 @llvm.vscale.i32() +; CHECK-NEXT: [[TMP3:%.*]] = mul i32 [[TMP2]], 2 +; CHECK-NEXT: [[MIN_ITERS_CHECK:%.*]] = icmp ult i32 [[TMP1]], [[TMP3]] +; CHECK-NEXT: br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]] +; CHECK: vector.ph: +; CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.vscale.i32() +; CHECK-NEXT: [[TMP5:%.*]] = mul i32 [[TMP4]], 2 +; CHECK-NEXT: [[N_MOD_VF:%.*]] = urem i32 [[TMP1]], [[TMP5]] +; CHECK-NEXT: [[N_VEC:%.*]] = sub i32 [[TMP1]], [[N_MOD_VF]] +; CHECK-NEXT: [[IND_END:%.*]] = add i32 [[IDX]], [[N_VEC]] +; CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement poison, i32 [[IDX]], i32 0 +; CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector [[DOTSPLATINSERT]], poison, zeroinitializer +; CHECK-NEXT: [[TMP6:%.*]] = call @llvm.experimental.stepvector.nxv2i32() +; CHECK-NEXT: [[TMP7:%.*]] = add [[TMP6]], zeroinitializer +; CHECK-NEXT: [[TMP8:%.*]] = mul [[TMP7]], shufflevector ( insertelement ( poison, i32 1, i32 0), poison, zeroinitializer) +; CHECK-NEXT: [[INDUCTION:%.*]] = add [[DOTSPLAT]], [[TMP8]] +; CHECK-NEXT: [[TMP9:%.*]] = call i32 @llvm.vscale.i32() +; CHECK-NEXT: [[TMP10:%.*]] = mul i32 [[TMP9]], 2 +; CHECK-NEXT: [[TMP11:%.*]] = mul i32 1, [[TMP10]] +; CHECK-NEXT: [[DOTSPLATINSERT1:%.*]] = insertelement poison, i32 [[TMP11]], i32 0 +; CHECK-NEXT: [[DOTSPLAT2:%.*]] = shufflevector [[DOTSPLATINSERT1]], poison, zeroinitializer +; CHECK-NEXT: br label [[VECTOR_BODY:%.*]] +; CHECK: vector.body: +; CHECK-NEXT: [[INDEX:%.*]] = phi i32 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ] +; CHECK-NEXT: [[VEC_IND:%.*]] = phi [ [[INDUCTION]], [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[VECTOR_BODY]] ] +; CHECK-NEXT: [[TMP12:%.*]] = getelementptr i64, i64* [[A:%.*]], [[VEC_IND]] +; CHECK-NEXT: [[TMP13:%.*]] = extractelement [[TMP12]], i32 0 +; CHECK-NEXT: [[TMP14:%.*]] = bitcast i64* [[TMP13]] to double* +; CHECK-NEXT: [[TMP15:%.*]] = getelementptr double, double* [[TMP14]], i32 0 +; CHECK-NEXT: [[TMP16:%.*]] = bitcast double* [[TMP15]] to * +; CHECK-NEXT: [[WIDE_LOAD:%.*]] = load , * [[TMP16]], align 8 +; CHECK-NEXT: [[TMP17:%.*]] = call i32 @llvm.vscale.i32() +; CHECK-NEXT: [[TMP18:%.*]] = mul i32 [[TMP17]], 2 +; CHECK-NEXT: [[INDEX_NEXT]] = add nuw i32 [[INDEX]], [[TMP18]] +; CHECK-NEXT: [[VEC_IND_NEXT]] = add [[VEC_IND]], [[DOTSPLAT2]] +; CHECK-NEXT: [[TMP19:%.*]] = icmp eq i32 [[INDEX_NEXT]], [[N_VEC]] +; CHECK-NEXT: br i1 [[TMP19]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]] +; CHECK: middle.block: +; CHECK-NEXT: [[CMP_N:%.*]] = icmp eq i32 [[TMP1]], [[N_VEC]] +; CHECK-NEXT: [[TMP20:%.*]] = call i32 @llvm.vscale.i32() +; CHECK-NEXT: [[TMP21:%.*]] = mul i32 [[TMP20]], 2 +; CHECK-NEXT: [[TMP22:%.*]] = sub i32 [[TMP21]], 1 +; CHECK-NEXT: [[TMP23:%.*]] = extractelement [[TMP12]], i32 [[TMP22]] +; CHECK-NEXT: br i1 [[CMP_N]], label [[L_EXIT:%.*]], label [[SCALAR_PH]] +; CHECK: scalar.ph: +; CHECK-NEXT: [[BC_RESUME_VAL:%.*]] = phi i32 [ [[IND_END]], [[MIDDLE_BLOCK]] ], [ [[IDX]], [[L_ENTRY:%.*]] ] +; CHECK-NEXT: br label [[L_LOOPBODY:%.*]] +; CHECK: L.LoopBody: +; CHECK-NEXT: [[INDVAR:%.*]] = phi i32 [ [[INDVAR_NEXT:%.*]], [[L_LOOPBODY]] ], [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ] +; CHECK-NEXT: [[INDVAR_NEXT]] = add nsw i32 [[INDVAR]], 1 +; CHECK-NEXT: [[TMP24:%.*]] = getelementptr i64, i64* [[A]], i32 [[INDVAR]] +; CHECK-NEXT: [[TMP25:%.*]] = bitcast i64* [[TMP24]] to double* +; CHECK-NEXT: [[TMP26:%.*]] = load double, double* [[TMP25]], align 8 +; CHECK-NEXT: [[TMP27:%.*]] = icmp slt i32 [[INDVAR_NEXT]], [[N]] +; CHECK-NEXT: br i1 [[TMP27]], label [[L_LOOPBODY]], label [[L_EXIT]], !llvm.loop [[LOOP2:![0-9]+]] +; CHECK: L.exit: +; CHECK-NEXT: [[DOTLCSSA:%.*]] = phi i64* [ [[TMP24]], [[L_LOOPBODY]] ], [ [[TMP23]], [[MIDDLE_BLOCK]] ] +; CHECK-NEXT: store i64 1, i64* [[DOTLCSSA]], align 8 +; CHECK-NEXT: ret void +; +L.entry: + br label %L.LoopBody + +L.LoopBody: ; preds = %L.LoopBody, %L.entry + %indvar = phi i32 [ %indvar.next, %L.LoopBody ], [ %idx, %L.entry ] + %indvar.next = add nsw i32 %indvar, 1 + %0 = getelementptr i64, i64* %a, i32 %indvar + %1 = bitcast i64* %0 to double* + %2 = load double, double* %1, align 8 + %3 = icmp slt i32 %indvar.next, %n + br i1 %3, label %L.LoopBody, label %L.exit + +L.exit: ; preds = %L.LoopBody + store i64 1, i64* %0, align 8 + ret void +} + +attributes #0 = { nofree norecurse noreturn nosync nounwind "target-features"="+sve" } +